# International Guild of Knot Tyers Forum

## General => Knotting Concepts & Explorations => Topic started by: agent_smith on July 12, 2011, 02:23:48 AM

Title: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on July 12, 2011, 02:23:48 AM

Specifically: An entanglement of rope/cord that possesses form and structure under tension with characteristics that identify it as belonging to a class of knots known as the Bowline.

At present, from what I can fathom, there is information/clues scattered about this forum - but no one coherent body of theory that defines a Bowline. So this is an attempt to bring together our collective knowledge into one place.

Obviously, this could be done for a few other knots as well...

Thus far, I have found the following information:-

Quote
The study of how the essential bowline structure can be employed/realized
in knots is helpful in finding "new" knots and understanding old.  To my
thinking, the sine qua non / essence of a bowline is the nipping loop;
I don't hold the bight collar to be key, just one way of forming a knot
using that loop.  And from a structural assessment, I find the
"double butterfly" (two eyes) to be a bowline variant (indeed, a good
candidate for the moniker "double bowline" !).

.:.  An easy-sounding question has more to it than one might suspect.

--dl*

and this (From DL):

Quote
Or is there some quintessential aspect of a *bowline* that qualifies
a knot to be so regarded (named "b." or not --a rose smells as sweet)?
This is a much better criterion, IMO, which will spare the minding of
Irish impostors and much of the nonsense coming from Hensel&Gretel's
make-believe land.....  The study of how the name "bowline" has been employed carries some
merit as a work in knotting history.  Unfortunately, it really entails a lot
of NEW work in trying to sort through the extant literature to figure out
which reports have any semblance of truth --a great deal of what's printed
amounts to hearsay from prior printed work.

and this - from xarax:

Quote
There are three, and only three elements that characterize a bowline, in relation to any other end of line loop:
1. The knot tied on the standing part s leg, should be a slip knot. Any sailor will laugh with an end of line loop that is not completely untied like the bowline. Smiley
2. This slip knot should include one, at least, nipping loop, which secures the tail.
3. The tail should form one, at least, collar.

and this (from Derek Smith):

Quote
I would argue for the KISS principle where the Bowline is a small number of loop knots based on the SBCore, and that we might consider calling a knot a Bowline variant only if it clearly contains the SBCore + embellishments.

As for the Janus, it does contain the simple hitch (AKA nipping loop) snugly holding and held by a bight loop, so it can rightly claim to be a Bowline variant, although so far removed from the basic Bowline as for that claim to be almost irrelevant - and what is wrong with simply calling it 'The Janus Loop'?  Containing the SBCore is no great claim to fame or function...

Derek

and this (from TheKnotGuy):

Quote
The question still remains, ?How many Bowlines are there??  Does the structure define the knot?  Or do we define the knot because of the nipping loop or the bight collar?  Or does a ?true? Bowline need both a nipping loop and the bight collar?  Once again, I don?t know, but the question still needs to be asked.

Some images to assist with identifying a Bowlines structure (Note: I am not suggesting that the so-called 'Janus' is in fact a Bowline - I am merely posting the image for thoughtful analysis)...
(http://)
(http://)
(http://)
(http://)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 12, 2011, 07:36:42 AM
Hi Mark,

Rather than simply posting a personal declaration of what makes a Bowline, I believe that it is important to include the reasoning that supports that position.  To that end, I am reposting the whole of the post I referred to :-

Quote
The Sheetbend has two elements, a bight loop and a simple hitch (often called the 'nipping loop').

The Bowline is simply the Sheetbend 'wired up' as an end of line loop.  It has identical elements to the Sheetbend.  It would be inconceivable to describe the Sheetbend as 'a nipping loop  - with or without the bight loop', and I hold that it is incongruous to describe the Bowline in any way other than we would describe the Sheetbend.

There are four 'ends' from the basic Sheetbend core, and these can be 'wired up' to form 'L' and 'R' basic Bowlines and 'L' and 'R' Eskimo bwls. (the bwls. made by wiring up the SP to either of the bight legs are biased towards spilling and are ignored as practical knots).

Recapping - the 'Core' or 'SBCore' structure is a bight loop with a simple hitch, which can function as a loop or as a bend.

(http://igkt.pbworks.com/f/1151665131/Bk-Blt03-sml.gif)     SBCore

Beyond this, you are into variations - doubling, TIB with refold security, enhancing the bight, enhancing the hitch and securing the 'end'...   but in all cases, to be a variation it should still contain the two basic components - the co-embracing bight loop and the hitch - the SBCore.

So, for something to be 'Bowlinesque', I hold that it must contain the SBCore elements, any embellishment beyond this core and you are into variants which should be described as SBCore(B or E, L or R) + Variation

Give it whatever variations you like and call it whatever crazy name you like - Bobs Bonkers Bowline - the Triple B - but please, only give it the Bowline appellation if it contains the SBCore  - the co embracing bight loop and hitch.

This leaves us with just four simple or 'true' bowlines and as many variants as you would wish to waste use your life inventing.

snip...

Derek

Applying this to the four knots you posed and we can see they all fit this definition of either Bowline (1010) or Bowline + variations.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 12, 2011, 08:42:35 AM
The bowline does not have a hitch in it, like the Sheet bend.
The bowline is a close relative of the Gleipnir, not of the Sheet bend.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 12, 2011, 10:20:51 AM
Very cool colour coding mods on agent smith's images Derek.

alpineer
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on July 12, 2011, 10:47:02 AM
Hi Derek (the dunny man!!),

Nice to hear from you...

Can you apply your magic brush to the Karash double loop to indicate why it is does not meet the topological/structural requirements to be classified as a Bowline?

I'll also post a photo of ABoK #1080 tomorrow... I particularly want to compare #1080 against the Karash double loop with your colouring scheme.

Mark
(http://)
(http://)
(http://)
(http://)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 12, 2011, 03:28:04 PM
Derek, with all respect, I have to say that you make a mistake here. ( Of course, you might well succeed in persuading me to change my mind, as you have done in the case of the Carrick mat / bend !  :) )
The bowline does not have a hitch in it, like the Sheet bend.  We can tie a bowline that holds satisfactory well, even if the collar is very loose. We can not do the same with a Sheet bend.
The bowline is a close relative of the Gleipnir, not of the Sheet bend. In the bowline, we simply replace the 50 % mechanical advantage that is offered by the second line that goes through the nipping loop, with the 50 % capstain advantage that is offered by the collar.
The Sheet bend does incorporate a hitch, just as the ABoK#1406, that is simply a doubled and symmetric Sheet bend (as such, it has two hitches.)
I know that we can spend the rest of our lives arguing about this, but why? Is nt it much better, and interesting, and useful, just to make another walk in the Knotland, with the hope we meet some new knots ?

Hi Xarax,

I can see that in order to make any headway here, I will have to demonstrate to your satisfaction that the  basic Bowline has the SBCore-i.e. that it incorporates a simple hitch...

I will start by conceding that under certain loading conditions the element in question is configured as a turned nip - as per the gripping element of the Gleipner, and in the Eskimo bwl the clamping function of the simple hitch is removed by the SP connection to the 'tail' of the hitch.  Having said that, it is when load is applied to the 'tail' of the hitch, that the very worse characteristic of the Bowline shows itself - i.e. loading on this leg of the loop risks an easy transformation from bwl to 'noose'.

In the spectrum of loadings that a Bowline will meet, the load will vary from 100% on the bight leg, right through to 100% on the 'hitch tail'.

When the load is full on the bight leg, the knot is working as a pure sheetbend and I hope you can agree, in that loading configuration, it IS a simple hitch.  At all other ratios of leg loadings, the hitch is functioning at some fraction as a simple hitch and some fraction as a 'turn-nip' - BUT - its function as the 'turn-nip' is the configuration we do NOT want to expose the bowline to.

Half convinced?

As for spending my life arguing about this - NO - not interested, but I can spare some time to share perspectives.

Derek

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 12, 2011, 08:21:06 PM
In the spectrum of loadings that a Bowline will meet, the load will vary from 100% on the bight leg, right through to 100% on the 'hitch tail'.

The bowline is a loop, where the loading on each of the two legs varies, but, most of the times, very closely around the natural middle value, that is 50% of the total load for each of the two legs. It is THAT loading configuration which will make us decide if the bowline resembles more a Sheet bend, or a Gleipnir ( and/or ABoK#160, ABoK#161).The fact that, at some few and extreme cases, "the knot is working as a pure sheetbend"  indeed, does not prove your point. In MORE cases, with MORE realistic loadings, the bowline is working as a Gleipnir with a collar.
In a bowline, none of the two legs of the collar are in a right angle with a segment of the standing part, as it happens with the Sheet bend ! In fact, they are almost parallel with it at the proximity of the nipping loop / the curved-around-360-degrees-segment of the standing end.

Title: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on July 13, 2011, 04:09:16 AM
Images of the Karash double loop and ABoK #1080 for direct comparison...

Mark
(http://)
(http://)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot4u on July 13, 2011, 07:54:05 AM
To the definition of a Bowline, I'd add the working end (or working bight) first passes through the nipping turn in a way that makes the structure at that point topologically equivalent to an overhand knot.  For the case of a Double Bowline, a working bight passes through the nipping turn to form a structure that is topologically equivalent an overhand knot structure.

In contrast, in the Karash Double Loop, there is no overhand knot equivalent at the point where the bight first passes through the nipping turn.  Where the bight first passes through the nipping turn, the structure at that point is topologically equivalent to a Figure 8 knot.  Thus, the Karash Double Loop is eliminated from the Bowline definition.

Play around around with the structures for awhile.  Thank me later.  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 13, 2011, 10:41:21 AM
Images of the Karash double loop and ABoK #1080 for direct comparison...

Mark
(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=4876;image)
(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=4878;image)

Hi Mark,

I have to congratulate you on a skilful piece of educating you have done on me here.

While the Karash does not have a simple hitch and therefore is not a Bowline, it does have the co-engaged bight and hitch.  So, by my own definition I must concede that,  the Karash IS  a Bowline Variant and I withdraw my previous statement.

Well Done.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 13, 2011, 12:47:25 PM
I believe that it is a self-evident truth, that has no need for any other justification :
If part of a knot is a bowlne, the whole knot remains a bowline - albeit a more complex one.
As part of the Karash loop is a bowline indeed, the whole double loop remains a bowline. Completing a knot can not erase a previously tied part of it, so, if a knot was a bowline, at one stage of its tying, it will remain a bowline, even after one adds some new parts on it.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 13, 2011, 01:34:40 PM
...  the structure at that point [is] topologically equivalent to an overhand knot.

There are two ways one can read this sentence, and both reveal mistakes.

1) There is a structure topologically equivalent to the overhand knot, on the standing part :

Of course not. Any knot that is tied on the standing part, with rope strands of the standing part, ( before the tail passes through it ), must be topologically equivalent to an unknot. ( that is what I mean by saying that it must be a slip knot : If we remove the segment of the line after the eye leg of the bight, the segment of the line before the eye leg of the standing part can, by pulling its two ends, be turned to a straight line, with no knotted structure on it. )

2)  We can speak of a structure topologically equivalent to a one line knot, even if we have two lines. So, even if there is no overhand knot tied on the first line, the standing part line, the local structure at the proximity of the nipping loop is topologically equivalent to the overhand knot, if we also consider the second line that passes through it - the segment of line after the eye leg of the bight.

No. We can not speak of the same or equivalent topology of a one loop knot, and of a two loops link ! We can speak of geometrical identities or similarities. And considering those geometrical qualities and quantities, there is no difference whatsoever at the proximity of the nipping loop, between the simple, common bowline and the Karash double bowline.

Play around around with the structures for awhile.  Thank me later.  :)
:)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot4u on July 13, 2011, 07:09:37 PM
You cannot tie a Karash Double Loop if you begin as if you are tying an Overhand knot (on a bight), but you CAN with every Bowline mentioned on this page:

In contrast, you begin the Karash Double Loop with a Figure 8 knot (on a bight).  For further explanation, I refer to my previous post.  In short, the Karash Double Loop is based on a Figure 8 knot, while the Double Loop Bowline and every other Bowline are based on an Overhand knot.  Even the Water Bowline?  Yes, even the Water Bowline.  If you don't see the Overhand knot, then keep looking.

As another example, the Double Dragon is also eliminated from the Bowline family because the working end does NOT enter the nipping turn such that the structure is topologically equivalent to an Overhand knot at that point.

Seriously, the term "Bowline" is already watered down enough.  Let's not water down the term even more to include knots that can be mathematically explained away.  Xarax, you can kick and scream all you want, but a Figure 8 is not equivalent to an Overhand.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 13, 2011, 07:25:23 PM
the Karash Double Loop is based on a Figure 8 knot on a bight, while the Double Bowline is based on an Overhand knot on a bight.

I have read 29 more times your previous post, and I have not understood anything more than the first tme. So, my previous post stands as it is. You could possibly read it 30 times, to check if you could gain anything, but you will live without doing this, of course... :)

The fact that you try to use the "overhand vs fig.8 " theory of yours to eliminate the Double Dragon (!) from the bowline family, or, fot this loop, any other theory, is an indication that you have not understood very well what a bowline is...Have you ever tied a Double Dragon on a ring, using the one end of the rope, while the other end is pulled by the boat that is pulled by the anchor chain ?  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot4u on July 13, 2011, 07:36:18 PM

1.  Tie an Overhand Knot on a bight.
2.  Without completely untying that Overhand Knot on a bight, can you tie a Karash Double Loop on that Overhand?
NO.

1.  Tie an Overhand Knot on a bight.
2.  Without completely untying that Overhand Knot on a bight, can you tie a Double Loop Bowline on that Overhand?
YES.

1.  Tie a Figure 8 Knot on a bight.
2.  Without completely untying that Figure 8 Knot on a bight, can you tie a Karash Double Loop on that Figure 8?
YES.

1.  Tie a Figure 8 Knot on a bight.
2.  Without completely untying that Figure 8 Knot on a bight, can you tie a Double Loop Bowline on that Figure 8?
NO.

...I submit the Overhand Knot structure is one defining structure within a Bowline that distinguishes the Bowline from other knots like the Karash Double Loop.  Again, the term "Bowline" is already watered down enough.  Let's not water down the term even more to include knots that can be mathematically explained away.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 13, 2011, 08:15:54 PM
Tie an Overhand Knot on a bight....

Is THAT the way you tie a bowline ? Well, 99,99 % of the bowlines tied each day are not tied that way...because they are used as end-of-the-line loops that :
1., can be tied by using only one end, and after this end has been driven through a ring, (or around a bollard), and
2., can be untied completely by removing the free end from any knot structure on the eye leg of the standing part,
If we can not do those two things,, then, of course, we do not have a bowline. But we can tie the Karash bowline that way, can t we ?
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot4u on July 13, 2011, 10:28:45 PM
A lot of noise, dude...

A Karash Double Loop is clearly not a Bowline, as explained by the tasks I gave in my last post.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 14, 2011, 12:24:45 AM
A lot of noise, dude...

Even the 1/30 th of it, that you manage to read ?  :)
I had never characterized "noise" what another person is trying to tell me.
A friendly advice : Some modesty does no harm to anybody. And some doubt about our beliefs/theories.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot4u on July 14, 2011, 08:40:38 AM
To further drive home my point, watch this video:

As shown in the video, you tie the Karash Double Loop by starting with a loosely tied Figure 8 on a bight.

Now, try this.  Instead of starting with a loosely tied Figure 8 on a bight, start with a loosely tied Figure 10 (Stevedore) on a bight.  Then, finish the knot as shown in the video.  If you are putting a Karash Double Loop in the Bowline family, then you also must put this knot I described in the Bowline Family.  If you continue with this same line of thinking (Figure 11, Figure 12, etc.), then the number of knots you must now include in the Bowline family is theoretically infinite.

That's absurd.  Let's not be absurd.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on July 14, 2011, 10:50:50 AM

From knot4u:
Quote
You cannot tie a Karash Double Loop if you begin as if you are tying an overhand knot (on a bight), but you CAN with every Bowline mentioned on this page:

and also:
Quote
you tie the Karash Double Loop by starting with a loosely tied Figure 8 on a bight.

I wanted to point out you do NOT need to begin from #1047 (figure 8 loop) to tie a Karash.

You can tie the karash by forming an overhand loop (doubled or 'on-the-bight') and then following the tying method depicted at #1080 and performing a 'backflip' maneuver.

However, after initially forming the overhand loop, you then need to induce an extra twist (or 180 degree U turn) by folding the working end back on top of itself (sort of like a Munter hitch on a double strand). Then you perform the #1080 backflip maneuver.

I think you are referring to #1081 and #1082 - which depict the use of an overhand loop on the bight as a starting point to arrive at a bowline on the bight. Both methods involve a 'backflip' maneuver however.

If I am understanding you correctly, your criteria is as follows:
All [double] Bowlines can be formed by starting from #1009.

My next step is to see if there is a way of tying the karash double loop from #1009. A theory is a 'proposed explanation' (or an "established explanation accounting for known facts or phenomena")...and all theories must be able to withstand attempts to prove otherwise.

Derek (the dunny man), what rationale are you using as the basis for your proposition that the karash is a Bowline variant? I thought your colored ropes idea had merit...

Mark
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: TheTreeSpyder on July 14, 2011, 01:37:40 PM
To me, a Hitch made to line itself on a single line is a Half Hitch (in perpendicular pull on spar form).  But this Half Hitch, made to a bight/ eye is a SheetBend / Becket.

Can also have a Half Hitch pulling inline on spar (if slid off end leaves no knot); but makes Marl(if slid off end leaves OverHand Knot) if Half Hitch perpendicular pull form is used and free end just pulled.

Bowline, is then a SheetBend to self to form fixed eye.

BoB, does same on bight by sneaking an inversion in the back door, but must be sure to complete the inversion until Standing is deformed into Half Hitch locking into bight/eye of the end of the bight of the whole arraingemeant.

Karash would seem to give similar inversion, but not from OverHand (as in BoB); but rather fig.8.  Must still make sure to carry the inversion all the way across to deforming the Standing into more of a fig.8 Hitch (Abok 1666) SheetBend to self.

Weather using a 1666 in place of a 1662; because it is more towards a better Nip of 1663(more ref. thru 1707) + more Frictions; disqualifies the form as a Bowline, i really can't say.  Except that the main change in the mechanic is more of a fig.8 Hitch than Half Hitch as locking Nip formed from Standing's immediate tensions.

Line can only resist/ support on the inline axis, and then only in the tension direction.  A line is strongest/ at potential strength when totally inline / straight; but mostly must be bent/ deformed from optimal straight to be used.  There are only so many of these base bends/ deformities possible; and they should be named and mechanically understood.  Also, should see same lacing as different mechanic / name per direction of force/pull/ flow on lacing.

One of my favorite strength retention references in Abok is 1669.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 14, 2011, 03:06:03 PM
Bowline, is then a SheetBend to self to form fixed eye.

TheeSpyder, it shows that you have gone to school, together with Derek Smith !  :)
As I have already argued at Replies #2 and #6, this theory is falsified by the simple fact that a Bowline can hold even when the collar is very loose, while the Sheet bend can not.
Have a look at ABoK#160 and ABoK#161. Do you see any elements of the Sheet bend there ? Do you see any elements of any hitch whatsoever ? Do you see segments of lines perpendicular to each other, as in the Sheet bend ? No ! But you see elements of the Bowline, of course ! And you see elements of the Bowline in the Gleipnir, too, which is nothing but a bowline-type of knot, where the capstan advantage of the collar has been replaced by the mchanical advantage of the second line.
The false theory of the close relation of the Bowline with the Sheet bend was, in fact, initiated by Ashley, who had not paid much attention to ABoK160 and ABoK#161 as structures that could evolved even further : that is why he missed the Gleipnir ! Had he met the Gleipnir, I am sure that he would have seen its close relation with the Bowline, at once.
The Gleipnir proved that the primary element of the Bowline is the nipping loop, and the secondary element the collar. If we did not know the Gleipnir, ( and the ABoK#160 and ABoK#161 ), we would be justified to see the relation of the Bowline with the Sheet bend, indeed, a relation that is more remote and less important that the relation between the Bowline and the Gleipnir.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot4u on July 16, 2011, 02:41:43 AM
I wanted to point out you do NOT need to begin from #1047 (figure 8 loop) to tie a Karash.

You can tie the karash by forming an overhand loop (doubled or 'on-the-bight') and then following the tying method depicted at #1080 and performing a 'backflip' maneuver.

However, after initially forming the overhand loop, you then need to induce an extra twist (or 180 degree U turn) by folding the working end back on top of itself (sort of like a Munter hitch on a double strand). Then you perform the #1080 backflip maneuver.

That's a slight of hand to avoid the issue...

Let's talk about single loops.  Tie a loosely tied Overhand.  Now, without without completely untying the Overhand, can you tie a Karash Single Loop on that Overhand?  I don't think so.  But I can tie other knots I know to be Bowlines.  Also, if I start with a loosely tied Figure 8, I can tie a Karash Single Loop on that Figure 8, but I can't tie other knots I know to be Bowlines.

Again, if you include the Karash Double Loop (or Single Loop) in the Bowline Family, then you must include an infinite number of other loops based on the Figure 9, Figure 10, Figurre 11, etc., as I explained in my previous post.

(http://i1221.photobucket.com/albums/dd468/iq201/Public/Loop-KarashSingle001a.jpg)
Karash Single Loop, Front

(http://i1221.photobucket.com/albums/dd468/iq201/Public/Loop-KarashSingle002a.jpg)
Karash Single Loop, Back
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on July 16, 2011, 03:51:02 AM
Quote from knot4u:  Posted on: July 13, 2011, 07:36:18 PM
Quote

1.  Tie an Overhand Knot on a bight.
2.  Without completely untying that Overhand Knot on a bight, can you tie a Karash Double Loop on that Overhand?
NO.

Actually, YES! You can.

Lets be 100% clear here. I am NOT stating that the Karash double loop is a Bowline! What I am stating is that your hypothesis does not hold up (at least with regard to your 'task A').

This thread is about defining a Bowline. I am seeking a robust definition - a workable theory. I think others would like to see such a theory also. I deliberately chose ABoK #1080 as a comparison to the Karash double loop because of the similar form. I thought this would be a great test of the theory. As I stated, you can tie a Karash double loop starting from ABoK #1009 (without untying #1009). I admit that you need to induce a half rotation to #1009 (sort of like a munter in form) before performing the #1080 backflip maneuver. But, you do not need to untie #1009!

I liked DerekSmith's hypothesis...that is until he did his own backflip ! DerekSmith's hypothesis was based on a particular form and structure which he was able to indicate clearly with the use of color.

knot4u, your hypothesis is based around #515 and #1009, in that, you must be able to tie a Bowline from one of these knots as a starting base. I think thats what your hypothesis is. Is this correct?

I am still hoping to hear more from DerekSmith in terms of argument/further theory on why he believes the Karash is a Bowline variant...perhaps with more coloration!

I am merely stating facts here...nothing more, nothing less.

Mark
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DDK on July 16, 2011, 06:35:02 AM
. . . As shown in the video, you tie the Karash Double Loop by starting with a loosely tied Figure 8 on a bight.   . . . Figure 10 (Stevedore) on a bight.  . . . (Figure 11, Figure 12, etc.), then the number of knots you must now include in the Bowline family is theoretically infinite.

That's absurd.  Let's not be absurd.

I believe knot4u has a legitimate point.  If the nipping structure is left out of the definition of a bowline, there is much that one could call a bowline.  This irreverently mocks the fact that the very simple bowline (ABOK 1010) is a relatively good start to a secure fixed loop.  As an example, the Karash SINGLE Loop is a lousy start to a secure fixed loop as it easily slips.  Those single loops that do not slip easily are, from what I've seen, more complex than the simple bowline.

DDK
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 16, 2011, 03:27:47 PM
Quote from knot4u:  Posted on: July 13, 2011, 07:36:18 PM
Quote

1.  Tie an Overhand Knot on a bight.
2.  Without completely untying that Overhand Knot on a bight, can you tie a Karash Double Loop on that Overhand?
NO.

Actually, YES! You can.
...What I am stating is that your hypothesis does not hold up

While not buying into Knot4U's criteria,
I do believe his assertion in "task A",
so I'll need to see what it is you think disproves that.
the direction of certain parts is opposite between
the two cited starting knots, and I see no way
around that to achieve the same result.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 17, 2011, 03:12:22 AM
I believe that it is a self-evident truth, that has no need for any other justification :
If part of a knot is a bowlne, the whole knot remains a bowline - albeit a more complex one.
As part of the Karash loop is a bowline indeed, ...

???  What is this part that is a bowline, please?

BTW, the single-strand structure corresponding to the so-called
"Karash double loop" is given in "Hensel & Gretel's" EKFR
as the "twist bowline" --for whatever that's worth (one might
surmise that they invented the name, if not the knot as well).

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 17, 2011, 03:20:45 AM
As an example, the Karash SINGLE Loop is a lousy start to a secure fixed loop
as it easily slips.

???  In what material & force(s) are you finding slippage?
I've tried a couple of materials and used a pulley, but see
no hint of slippage.  (Btw, Mr. Karash had the twin-eye
knot tested to rupture, and it performed well, in some
low-elongation kernmantle (11mm or thereabouts) rope,
IIRC.)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 17, 2011, 03:29:34 AM
How do the debaters here classify Ashley's #1033,
the carrick loop --which begins exactly as #1010
through the turn around the SPart with the tail,
but then takes the tail (instead of immediately passing
back out through the nipping loop) over the SPart-side
eye leg and then out through the central nipping loop
but in the same direction (vis-a-vis loop's *side*)
as it entered (i.e., so that it could now trace the
first pass of the tail for a 2nd course).

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 17, 2011, 05:58:52 AM
As an example, the Karash SINGLE Loop is a lousy start to a secure fixed loop as it easily slips.

In slick braided poly I've found the Cowboy Karash Single doesn't slip(under manual tension), however the Regular Karash single will. If the cowboy version doesn't slip under higher loading I would have to say that I am very impressed with this knot.  In nylon cordage my guess is the Karash Double does a good job of isolating each eyeloop from the other by very simple locking mechanism.  Even as a Cowboy Sheet Bend type of knot it seems to be a very secure knot.  In cyclic loading any slack in the collar is taken up by the loaded leg and not the tail. For the record I don't consider the Karash to be a Bowline. It doesn't have Derek's cited SB Core form. In the Knotting world "function follows form".

alpineer
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 17, 2011, 06:03:31 AM
How do the debaters here classify Ashley's #1033,
the carrick loop --which begins exactly as #1010

Certainly not as a Bowline, if that's what you're getting at.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 17, 2011, 07:33:11 AM
How do the debaters here classify Ashley's #1033,the carrick loop

Read my lips : No collar = no bowline (*). I know you do not cosider the collar as an essential element of the bowline...but I do :). I agree that the principal element is the nipping loop ( just as it happens in the case of the Gleipnir,),  but, to my mind, the collar is also un indispensable element, albeit of a lesser importance. I have seen bowlines holding with very loose collars, but not with very loose nipping loops !  :)
* Of course, by the most common definition of the "collar" (which is exactly what the bowline has - and the Gleipnir has not.) So, yes, with a collar - defined that way -, when the working end re-enters the nipping loop, it has to point to the opposite direction than when it exits from it.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot4u on July 17, 2011, 04:49:49 PM
For those who say a Karsah Double Loop is a Bowline, do you also put a Figure 8 Double Loop in the Bowline Family?  If you don't, then how do you describe the line of distinction?

http://www.animatedknots.com/fig8loopdouble/index.php
(http://i55.tinypic.com/2uthjlt.jpg)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 17, 2011, 06:32:14 PM
do you also put a Figure 8 Double Loop in the Bowline Family?

Read my lips : No knot-that-can-be-fully-untied-with-the-removal-of-the-tail(s) off the standing part(s) = no bowline. (1) I know that you do not consider this characteristic to be an essential element of the bowline...but I do...   :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot4u on July 17, 2011, 08:05:04 PM
Yeah, I'm not sure why you shortened an already short question.  Both parts of my question were necessary.

First part...Do you put a Karash Double Loop in the Bowline Family?  If no, then there is no need to continue.  If yes, then (Second part), what is the line of distinction between the Karash Double Loop and the Figure 8 Double Loop, such that one is a Bowline while the other is not?

I read your answer, Xarax.  Through all your rhetoric and hand waving, it is still unclear to me where the line of distinction is.  Or maybe by default you also put the Figure 8 Double Loop in the Bowline Family?
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 17, 2011, 11:28:19 PM
Do you put a Karash Double Loop in the Bowline Family?

Make an educated guess...What does the following answer - that you have read, as you claim - does say, in a plain and CLEAR way ? Does it say that the Karash double loop IS NOT a bowline ?  :)

If part of a knot is a bowlne, the whole knot remains a bowline - albeit a more complex one.
As part of the Karash loop is a bowline indeed, the whole double loop remains a bowline. Completing a knot can not erase a previously tied part of it, so, if a knot was a bowline, at one stage of its tying, it will remain a bowline, even after one adds some new parts on it.

what is the line of distinction between the Karash Double Loop and the Figure 8 Double Loop, such that one is a Bowline while the other is not?

The reason why the Karash double loop IS a bowline, is given in the answer above, that now you have read, I hope !  :)
The reason why the figure 8 Double loop IS NOT a bowline, is already repeated many times, but I would make just another attept : The figure 8 knot, tied on the eye leg of the standing part of a figure 8 Double loop, is not an unknot - it can not be removed after we remove the segment of the tail that goes through it.

No knot-that-can-be-fully-untied-with-the-removal-of-the-tail(s) off the standing part(s) = no bowline.
After a sailor has removed the tail from the eye leg of the standing part, he wants the bowline to turn onto the unknot immediatelly, so it will not run the danger to be caught somewhere, as the ship leaves the dock. So, even before the end of the line exits through the mooring ring, for example, the bowline should have been untied completely. If you are left with a figure 8. knot on your mooring line, you will probably forced to be an armchair only knot tyer, very soon !  :)

Make an educated guess...What does the proceeding answer - that you have read, as you claim - does say, in a plain and CLEAR way ? Does it say that the figure 8 loop IS a bowline ?   :)

it is still unclear to me where the line of distinction is.

Let me help you here a little bit, because THAT IS the most difficult point, indeed...  :)
The Karash double loop IS a bowline, while the figure 8 double loop IS NOT a bowline !  :)
That is a somehow CLEAR line of distinction, to me...
Of course, you can find many other, secondary reasons why two different knots are different, I suppose... I would be nterested to learn them, too, however insignificant they might be, because any difference of two different entities can reveal something essential from the deeper identity of each of them.

Or maybe by default you also put the Figure 8 Double Loop in the Bowline Family?

Did I say that you should have read my answers by now ? Well, this question makes me wonder if I should really be so sure !  :) If you could could only listen and see my "rhetoric and hand waving" to myself now...

Knot4u, please, let us be liberated, at least for some time, from this sterile exchange of opinions ( among other things...  :)) about this Karash-double-whatever, that I, personally, do not find such a clever knot... In my reply to a thread that you, too, have participated, (1), I have published the pictures of a particular dressing of a ,double loop that might be of some interest to you. Let us talk about double loops then, a very interesting and vast subject !

1) http://igkt.net/sm/index.php?topic=3046.0
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 18, 2011, 06:15:19 AM
How do the debaters here classify Ashley's #1033,
the carrick loop --which begins exactly as #1010

Certainly not as a Bowline, if that's what you're getting at.

C'mon, you know that this cryptic answer begs the question why (not)? !

To my mind, it has exactly the central turNip that is essential
to being "a bowline" --and differs only a little in the reeving
of the tail to stabilize the knot.

So, you're on : if not "bowline", then what?
And why not ..., btw.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 18, 2011, 06:25:10 AM
I believe that it is a self-evident truth, that has no need for any other justification :
If part of a knot is a bowlne, the whole knot remains a bowline - albeit a more complex one.
As part of the Karash loop is a bowline indeed, ...
???  What is this part that is a bowline, please?

Please, read more than 1 out of 30 what I write...otherwise, you will be right to consider what you read as a "noise", I suppose.

And then, with that gratuitous admonishment, you go on to
ramble off-topic about some game-playing notions --providing
fuel to the flame that maybe only 1-of-30 of your words addresses
the issue!

When the answer sought is given only later, sans introduction,
as :
The "Karash" bowline is... a worsened bowline, because its not-retraced-yet form is but a "twisted nipping loop" bowline.
(See attached picture) The nipping loop, being twisted and inverted like this, is only a worse nipping loop, as much of its
nipping / constricting power is lost around the U turn of the eye leg of the standing part.

WHICH IS A QUOTE FROM ANOTHER THREAD!!
You win the prize, for this.

>:(

Now, as far as there being some equivalence --some family heritage--
between the turNip of the bowline and this crossing knot
coyly regarded by you as merely a "twisted nipping loop",
you're on your own with this.  I don't accept it as a reasonable
distinction.  (And, as you admit, the nipping mechanics are different
between these forms.)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 18, 2011, 08:13:37 AM
How do the debaters here classify Ashley's #1033,
the carrick loop --which begins exactly as #1010

Certainly not as a Bowline, if that's what you're getting at.

C'mon, you know that this cryptic answer begs the question why (not)? !

To my mind, it has exactly the central turNip that is essential
to being "a bowline" --and differs only a little in the reeving
of the tail to stabilize the knot.

So, you're on : if not "bowline", then what?
And why not ..., btw.

--dl*
====

If, as you suggest, Ashley's #1033 is a Bowline, then by your criteria you must also include an EyeLoop version of Ashley's #1406 Whatnot, which differs from ABoK #1034.5 only tail wise.
That Carrick loop, in it's finished form, shows a munter base shape as it's central structure and not a nipping loop.
As for what it is, well, I'm happy calling it a Carrick.

alpineer
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 18, 2011, 01:51:56 PM
...as you admit, the nipping mechanics are different between these forms.)

True, and the one is far superior to the other ! But the worse of them IS a nipping loop nevertheless ! The fact that the nipping mechanics are different, indeed, does not make the one a genuine "nipping loop" and the other a "not-nipping" loop !  :)  Only a worse nipping loop...
There are many other forms of more complex nipping loops we have discussed in this forum, and you, ( at least a finger of yours... :)), should remember very vividly. The Pretzel double nipping loop, the Constrictor/Transom double nipping loop, etc. They are more complex, indeed, and we are not yet able to prove that they nip better than the single nipping loop, the nipping mechanics are different, indeed - but this does not turn them into "non-nipping" loops !
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 18, 2011, 02:01:53 PM
That Carrick loop, in it's finished form, shows a munter base shape as it's central structure and not a nipping loop.

I agree that the Carrick loop is not a bowline, (1), but only because it does not have a proper collar, not because it does not have a proper nipping loop ! Could you, please, elaborate a little more on your statement above ? Could you also provide some pictures of a tightened Carrick loop, where we can see if we do have a nipping loop or not ?

1)http://igkt.net/sm/index.php?topic=3233.msg19430#msg19430
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 18, 2011, 06:45:24 PM
I agree that the Carrick loop is not a bowline, (1),
but only because it does not have a proper collar,
not because it does not have a proper nipping loop !

What happened to the maxim that if part of the knot IS a <particular_knot>
then it must remain so with the addition of other parts?  #1033 can
have a turNip just as does the bowline , and certainly has "at least
one...collar" (oh, dear, I omitted the weasel-word "proper", didn't I?)
--in fact, one can see two collars, in the loose form (which has no
crossing-knot/Munter  base).

That Carrick loop, in it's finished form, shows a Munter base shape as it's central structure and not a nipping loop.

How does one know when the knot's "finished" ?
--might depend upon one's goals for it.  But you followed
the bait into the classification problem for this knot, to our
minds (not X's, who sees a broader concept of "nipping loop") :
the geometric form that we'd like to base classification on is
set towards the boundary area between distinct forms.

.:.  I think we just shrug and acknowledge this problematic aspect,
rather than make contortions to definitions in an attempt to deal with it.

(Btw, as the carrick bend provides a better form for an eyeknot,
I don't like Ashley's use of the name here.)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 18, 2011, 07:15:24 PM
I agree that the Carrick loop is not a bowline, (1), but only because it does not have a proper collar
IMO both the simple nipping loop and the bight collar must be present in the bowline description. I exclude the Karash from the bowline family because it also has this munter structure(which you call a "worsened" nipping loop). I submit to you that it has an "improved" nipping component due to the mechanical advantage of turning around it's S.Part(though there may be exceptions due to friction). This difference justifies a separate classification apart from the more simple nipping loop structure.
Quote
Could you also provide some pictures of a tightened Carrick loop, where we can see if we do have a nipping loop or not ?
I'm sure that you know what it looks like xarax. If you feel that others need photos; you're so much better at that than I am.

alpineer

P.S. I don't expect you to do my "dirty work" re pictures, just that I am too busy doing other things, one of them being a post on a new method for tying the... coming soon.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 18, 2011, 07:29:17 PM
(Btw, as the carrick bend provides a better form for an eyeknot,
I don't like Ashley's use of the name here.)
--dl*
====
Yes, I would agree.

Quote
But you followed the bait into the classification problem for this knot
May I have some condiments with that bait, please. ;D

alpineer
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 18, 2011, 08:05:06 PM
#1033 can have a turNip just as does the bowline

Last time I checked in the ABoK, ABoK#1033 could have had one, at least, "proper" collar, but it did not ! I do not believe that Ashley re-edited his book so soon !  :) In case you have not noticed it, ABoK#1033, variation DL, with a "proper" collar, is an already known knot, and it is called "bowline".  :)

...a broader concept of "nipping loop"

We have four distinct strategies : The first is to have a broader concept of the collar, like you do, and the second is to have a broader concept of the nipping loop, like I do. The third is to have both, and the fourth is to have none of them... I will not hesitate to adopt the one or the other, or both, or none, provided this help us study better the knots we already know, and the knots we are going to learn, if we adopt any one of the those four strategies.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 18, 2011, 08:23:26 PM
I submit to you that it has an "improved" nipping component due to the mechanical advantage of turning around it's S.Part (though there may be exceptions due to friction). This difference justifies a separate classification, apart from the more simple nipping loop structure.

I really do not know, I can not tell, we have to measure it !Here is the simple common nipping loop, and here is the twisted nipping loop, or crossing knot. Who is going to test those things ? I would also like the Pretzel nipping loop, and the Clove nipping loop, and the Constrictor/Transom nipping loop to be tested...but I do not see any volonteers around.
( The above mentioned effect, if it really esists, it is not a mechanical advantage in the sense of pulleys, it might be in the sense of levels).
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 18, 2011, 08:57:24 PM
While I accept that knots made by the same basic methods (such as collapsing a slipped OH or a constrictor) are likely to contain the same or similar components, I am afraid that I cannot support the concept that the tying method in any way defines a knot.

In support of this position, take the example of a knot which can be constructed by a number of different methods - rabbit round the tree - climbers twist and wrap - one handed - Inkies wrap and twist - slipped OH - etc.  If I make a knot by any of these methods and give it to you for inspection, you will have no way of determining the method I had used...  The finished knot is a function of its structural components and NOTHING to do with its tying method.  The knot bears no witness or memory of its method of construction so we should not think of the finished knot in terms of how it was made, but in terms of what it 'is' and what it 'does'.

Historically, trades passed on their knowledge through apprenticeships, and knots were taught by methods often specific to a particular trade.  This history is dragging itself into our present way of thinking, but I hold that this is a wrong minded approach to understanding and categorising knots.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 18, 2011, 09:05:46 PM
There has been considerable talk of defining a Bwl by its nipping loop.

OK, if anyone is more than half serious about this, try to make a Bwl without its other key component - its bight loop...  then show us it in action.  Only then will I concede that a Bwl has one component, not two - a simple hitch (turnip) holding and being held by a bight loop - i.e. the SBcore.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 18, 2011, 09:38:32 PM
@Mark,  you asked for my justification for calling the Karash a Bowline Variant.

The first image clearly shows the bight loop in green.  Don't get confused with the second (double) Karash loop, the bight loop would function just as well with one loop or two, the key is that it is a bight loop containing and bearing against and contained by - a hitch.

The second image shows the part of the knot which provides the simple hitch functionality (red) via the variant structure (a twist) in yellow.

It is a bowline by the definition I offered because it has the bight loop and the hitch, but it is a variant because it has a variant hitch.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 18, 2011, 11:11:29 PM
Here are the pictures ordered by alpineer, and delivered by me...  :)
The heavy gun of Dan Lehman does not seem like a bowline at all, I am afraid, but not because it does not have a nipping loop ! Its nipping loop is there, in every dressing of this knot. What is missing though is the collar. And, please, do not confuse the nipping loop with a collar : A structure is either a nipping loop or a collar, it can not be both of them, simultaneously !  :) The essence of the collar is that, when the tail passes around the standing end and returns to its nest, the tensile forces on the second leg of the collar are greatly diminished, so the tail is secured by the nipping loop s action on it very easily. If the second leg of a bight is tensioned as much as the first, we do not have a collar, we have a nipping loop . And if the second leg of a bight is not loaded at all, we do not have a nipping loop, we have a hitch.
I think that this Carrick bend (ABoK#1033) seems more like the Perfection loop / Angler s loop (ABoK#1017, #1035) than a bowline, and Angler s loop is not a bowline ! ,
Now, the ABoK#1033, in its capsized as well as in its not-capsized form, does seem to incorporate a hitch, indeed,  that is, it seems to obey the theory of Derek Smith, MUCH more than the simple bowline...
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 18, 2011, 11:44:07 PM
a simple hitch (turnip) holding and being held by a bight loop

1. The nipping loop is not a hitch. When a bight has both its ends loaded, and it is nipping a line that goes through it, it is a nipping loop. When a bight has only one of its ends loaded, it is a hitch. BIG, HUGE difference !  :)
2. The collar is not a hitch. A hitch has its second leg pressed under its first leg ( on some other tensioned rope strand or rigid surface). A collar has its second leg nipped by the nipping loop, and secured because of the action of the nipping loop on it ( which, after its turn around the tree, does not pull as hard as before, so the nipping loop has a much easier job to do...) The second leg been secured by the nipping loop, not by the first leg. BIG, HUGE difference !  :)

As you might have guessed by now, my purpose is achieved : By 1) and 2), it is proved that there is no hitch present in the bowline !  :)
If one wishes to discover a hitch, he must search for it in the Carrick bend (ABoK#1033), or in the Angler s loop (ABoK#1017, ABoK#1035). It is a lot easier for one to find a hitch there, indeed, it is only there that one can find a hitch !
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 18, 2011, 11:53:28 PM
While I accept that knots made by the same basic methods (such as collapsing a slipped OH or a constrictor) are likely to contain the same or similar components, I am afraid that I cannot support the concept that the tying method in any way defines a knot.

In support of this position, take the example of a knot which can be constructed by a number of different methods - rabbit round the tree - climbers twist and wrap - one handed - Inkies wrap and twist - slipped OH - etc.  If I make a knot by any of these methods and give it to you for inspection, you will have no way of determining the method I had used...  The finished knot is a function of its structural components and NOTHING to do with its tying method.  The knot bears no witness or memory of its method of construction so we should not think of the finished knot in terms of how it was made, but in terms of what it 'is' and what it 'does'.

Historically, trades passed on their knowledge through apprenticeships, and knots were taught by methods often specific to a particular trade.  This history is dragging itself into our present way of thinking, but I hold that this is a wrong minded approach to understanding and categorising knots.

Derek

I quote this text word by word because it has to be at more than one place, so it will have a much lower probability to be erased by accident, by a computer bug or something. It would be great if I had been able to write it, but it was great to read it as well.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on July 19, 2011, 04:42:50 AM
DerekSmith, can you please apply your coloration to the following knots and therefore also apply your hypothesis for all to see?

EDIT: If I'm understanding your hypothesis correctly, the Carrick loop #1033 does not have a bight loop/collar that is fully encircled and gripped by a nipping loop. Therefore, the Carrick loop is not a Bowline. In examining the single Karash loop, it appears by my eye to have a bight loop/collar that is encircled and gripped by a nipping loop - although in this case the nipping loop is a variation due to its unusual added half twist. Now I'm try to apply your hypothesis to the Sheet bend #1431 to see where this structure belongs!

NOTE: The first image shown (#1010) is a control image.

All images courtesy of your friendly agent smith...(first 3 images taken against a white background in full natural sunlight using a flash).

Thanks, Mark

EDIT: Sheet bend added (NOTE: Photo of sheet bend taken indoors against a white backboard using 2 high intensity light sources - no flash used).
(http://)
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Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 19, 2011, 03:29:29 PM
Personal preference I suppose, Mark, but I do find your images easier on the eyes.

alpineer
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 19, 2011, 09:00:15 PM
Here are the pictures ordered by alpineer, and delivered by me...  :)
The heavy gun of Dan Lehman does not seem like a bowline at all, I am afraid,
but not because it does not have a nipping loop ! Its nipping loop is there, in every dressing of this knot.
What is missing though is the collar.

Your ability to force square pegs into round holes is impressive
--of stubbornness.
Just slacken the white rope's completion of #1033 and you'll
see not one but TWO collars appear; that should satisfy even
the most hungry bowline-seeking appetite.
(They might even appear as set, with greater forces and elastic
cordage.)

Quote
We have four distinct strategies : The first is to have a broader concept of the collar, like you do,

Rather, I don't stipulate "collar" in my definition of "bowline",
which you do.  Maybe I see a *collar* where you don't, also;
but my What is a *bowline*? concern is centered on the turNip
--which somehow must be pretty well stabilized (though there
are issues with deformation under load, poor/loose setting,
and so on).

Now, to Derek's
Quote
There has been considerable talk of defining a Bwl by its nipping loop.

OK, if anyone is more than half serious about this, try to make a Bwl without its other key component - its bight loop...  then show us it in action.  Only then will I concede that a Bwl has one component, not two - a simple hitch (turnip) holding and being held by a bight loop - i.e. the SBcore.

My quick answer to this is "Myrtle eyeknot" --the turNip
otherwise secured.  One can also consider the so-named Eskimo bowline
--which collars an eye leg and ... <does what to?> the SPart.

Quote
The finished knot is a function of its structural components and NOTHING to do with its tying method.
The knot bears no witness or memory of its method of construction
so we should not think of the finished knot in terms of how it was made,
but in terms of what it 'is' and what it 'does'.

For the purposes of knot classification, I'm happy with this statement;
but for the purposes of understanding the knot's behavior, I disagree:
a knot might well "have memory" of its tying method --in torsion of parts,
e.g..  (I have been amazed to find not only one but TWO kernmantle
rope testers[f] who tested the fig.8 eyeknot as both "re-threaded/-woven"
and "on a bight" !!  --as though the knot cared, as you say.  BUT, IFFFF
one were to sample actual tyers of said knot --as an in-the-field research
study, hands-on data collection, one MIGHT find e.g. that different
forms of the knot (which is after all never precisely specified) obtained,
that (suppose...) when tied in-the-bight it was usually so-dressed and
this end loaded, but was otherwise when "re-woven".  Of course,
one's test data then, if showing some difference, would be evidence
of the different forms of the knot.

Well, I'm not so happy with "what it does", as in the case of some
(what I call) "noose hitches" what is done might depend upon the
material & force --the midshipman's hitch not fixing an eye,
and two half-hitches being adequately called a "noose" by
structure, *hitching* to itself, a compound *structure*, not a knot
(the clove hitch finish being the *knot*).

[f](CMC Rope Rescue Manual and Dave Richards are the two testers
who did this, of whom I'm aware --published reports.)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 20, 2011, 12:20:26 AM
Your ability to force square pegs into round holes is impressive--of stubbornness.

Look who is talking - of stubbornness !  :)

you'll see not one but TWO collars appear; that should satisfy even the most hungry bowline-seeking appetite.

Had your stubbornness, even for a moment, made you dream that I would not have thought this desperate escape route for you ?  :) Read my lips ":

please, do not confuse the nipping loop with a collar : A structure is either a nipping loop or a collar, it can be both of them, simultaneously !  :) The essence of the collar is that, when the tail passes around the standing end and returns to its nest, the tensile forces on the second leg of the collar are greatly diminished, so the tail is secured by the nipping loop s action on it very easily. If the second leg of a bight is tensioned as much as the first, we do not have a collar, we have a nipping loop . And if the second leg of a bight is not loaded, we do not have a nipping loop, we have a hitch.

The collar is not any U turn of a segment of the rope...The collar is a U turn of the tail, it is a mechanism of the tail, a means of the tail to be secured easier by the nipping loop. The collar has both its legs going into the nipping loop from the same direction, i.e., the working end, when it enters the nipping loop - as the second leg of the collar-, is pointing to the opposite direction than the direction it has when it exits from it - as the first leg of the collar. So, the two legs of the collar are, more or less, parallel to each other.
Also, the nipping loop is not any 360 degrees turn of a segment of a rope...The nipping loop is a 360 degrees turn of the standing part around the tail, it is a constricting mechanism that nips the tail, a mechanism to secure the tail.
It is absurd to talk about collars on the standing part, and nipping loops on the working end / tail !
What you think you see on ABoK#1033, is not a collar ! It is a nipping loop on the standing part and/or a U turn of the line of the standing part.

a knot might well "have memory" of its tying method --in torsion of parts,

I agree with that.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on July 20, 2011, 06:18:01 AM
Another structure to study in detail...the Eskimo bowline. This time showing it with the control #1010.
(http://)
(http://)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 20, 2011, 08:06:38 AM
Agent Smith, I think that you follow the convention to name as the "front" view of the bowline, the view where the (first) nipping loop is shown with the standing end passing over the eye leg of the standing part. So, in order to compare two or more of the various members of the bowline family and other similar end-of-line loops, it is better, I believe, if we put side by side pictures of the front or/and the back view of the one loop, with pictures of the front or/and the back view of the other, respectably. This view of the Eskimo bowline iis the back view. ( Oh ! did I say "the" Eskimo bowline , and not "the so-called" Eskimo bowline ? Have I seen something in the Eskimo bowline where nobody else sees anything at all ?  :))
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 20, 2011, 05:05:51 PM
Hi Mark,

I am more than a little disappointed you think so little of my abilities to appreciate functional structures, that you give me a pretty little woven decorative mat under the pretence of it being a Carrick loop.

This is typical of the situation where a knot is made using a method that is memorable, but the structure tied then has to morph/capsize into the stable working knot.  It is also an example of a working knot being given a name from the method of making it - in this case, from the Carrick mat.

Calling the Carrick mat a Carrick loop is like calling a Tucked, Slipped OH (TSOH) a Bowline...  the TSOH is an intermediate, memorable or easily created, but still only an intermediate - only when the intermediate is finally morphed does it become the target structural working knot.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on July 21, 2011, 12:40:19 AM
Hi DerekSmith,

Not sure what you're actually trying to tell me here...?

Am only the guy who is snapping photos to try to assist others (such as yourself). And, I want to understand the structure of a Bowline.

At post #49 above, I posted images of a few structures (and at #53), the 'Carrick loop' #1033 included (that's what Ashley refers to it in his masterpiece). I tried to keep the dressing loose and easy to draw direct comparison to the 'control' structure of #1010. I was hoping you might be able to apply coloration to all the above images.

As for your abilities, I think very highly of them :) and have strong respect guys like you and Dan. Maybe I'm missing some British humor here...perhaps you're joking!?

I think there is a real opportunity here for some great thinkers to make a breakthrough...I happen to have a little remaining spare time for this work - but that time is running out. Its not often in life where you get opportunities like this one where so many very knowledgeable people can direct their minds to such a complex problem. I see this time period (right now) as a narrow window of opportunity...

Anyhow, would certainly appreciate if you could continue to apply your hypothesis (and coloring) - because I think we are getting closer to a working theory of the Bowline.

Mark
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 21, 2011, 07:33:57 PM
Calling the Carrick mat a Carrick loop is

... but still only an intermediate - only when the intermediate is finally morphed does it become the target structural working knot.

It's not perspicuous to what you refer, except that "Carrick" occurs
only in one place, and ... --inferences follow that.

What Agent_Smith shows is relatively accurate of what can obtain
from tying; and this knot structure has its turNip much like the
Gleipnir's orientation of it.  (Or, if one hauls harder on the tail
in setting the knot, one gets a sort of crossing knot base, which
was the issue I let Alpineer draw out, as a classification problem.)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 23, 2011, 11:02:52 PM
Hi DerekSmith,

Not sure what you're actually trying to tell me here...?

Am only the guy who is snapping photos to try to assist others (such as yourself). And, I want to understand the structure of a Bowline.
snip...

Mark

Hi Mark,

It seems confusion rules - OK  -  and there was me thinking that I was trying to help you...

But I think that your last post and Dan's subsequent post have both helped identify what might be clouding the issue, and that is that just about everybody I know thinks of, and represents, knots in the form in which they are made.  This is fine for knots that are made in virtually their final working configuration (i.e. sheetbend etc.)  but for knots like the Carrick, it is a confusion that tends to lead people to think about the functioning knot while holding the Josephine Knot image in their minds eye.

While Ashley clearly made the distinction between the decorative weave - the Josephine Knot - and the functional Full Carrick Bends (#1428 and #1439), he then repeatedly falls into the trap of depicting the Carrick as it is made - i.e. as the Josephine.  Only once does he depict the Carrick in its working form -

From ABoK  pp263
(http://knotbox1.pbworks.com/w/file/fetch/43601692/ABoK-Carrick.jpg)
The CARRICK BEND, when under stress, pulls up into easy loops,
which may be readily opened with a few light taps from a belaying
pin, fid, or other implement. It may be water soaked indefinitely,
and even then it will not jam.
Sometimes the CARRICK BEND is illustrated with the ends both on
one side (#1428) instead of diagonally opposite, but this is not so
secure. At sea it is tied as shown here.
Lescallier gives the knot by name in 1783.

Following this example, even you have depicted the Carrick as the Josephine weave, and Dan supports this by stating that your image depicts a structure which is "accurate of what can obtain from tying;" - and this all stems from the way the knot is made - virtually nobody thinks about the way the knot WORKS.  As we are dealing with practical, i.e. 'working', knots then we are dealing with 'Force Machines' whose function is utterly dependant upon their structure under load.  At least Ashley accurately declared "The CARRICK BEND, when under stress, pulls up into easy loops,".  It is this 'easy loop' structure we need to be considering when we think about what makes a Carrick vs what makes a bowline.

Even Xarax has a penchant for depicting knots in all their beautiful 'as tied' symetry, as commented on by Dan "Your ability to force square pegs into round holes is impressive", and I have to admit that until I started to pit one knot against another to destruction, I also toyed with structures devoid of loading impetus.

It was partly my work with loading knots, partly my work on attempting to develop a means to create a knot's signature (Overs Index and Binary Signature) and partly my attempts to create a 'Drawing Program', that led me to the perception of key functional components.  You have alread met the first two - the Bight Loop (or Bight Collar), and the Simple hitch.  One of each makes the SBCore I described earlier, two 'Bight Loops' make the Reef square knot, while two simple hitches can make either the Granny or the Whatknot.

So now it is time to introduce you to the third component - The Carrick Component.

First make a Full Carrick (#1439) and load it to make it morph into the 'easy loops' working structure.
Now, without changing its structure, loosen it off slightly, and completely remove one cord while keeping the structure of the other cord firmly in place.  If you paid attention to the component you removed and are able to recreate it, you will see that they are identical - they are The Carrick Component  (CC).

As you have seen, this third component can be compounded to itself - the Full Carrick.  It can also be compounded with either of the other two components we have so far seen - the Bight Component (BC) and the Simple Hitch Component (ShC), making three basic bends -
CC..CC- Full Carrick
CC..BC
CC..ShC
to go with the ones already seen
BC..ShC  - Sheetbend
BC..BC   - Square knot
ShC..ShC - Granny or Whatknot

Naturally, any of these hitches can be reconfigured as a loop knot.

As I have already proposed a definition for the Bowline - a loopknot made from BC and ShC (the SBCore).  The Carrick Component is (for this discussion) a new component, therefore, no knot containing it (by the proposed definition) is a Bowline.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 24, 2011, 02:41:38 AM
Derek, I do like your attempt to reduce the working of any practical knot in just a few basic elementary mechanisms. I have also attempted something like this, so I know it is mind-seducing to the point it may well hide from us an obvious fact. And the obvious fact here is that there is no sheet-hitch mechanism in the bowline...because the bowline collar is not a hitch. A hitch is defined by the asymmetry of its two legs, we can not have any hitch where the one leg is not passing over and the other is not passing under...as it happens in the sheet band. In a collar, the two legs are almost parallel to each other, as they enter and as they exit the nipping loop. I understand that you believe that the sheet bend is more elementary than the bowline, so you are trying to explain the bowline in terms of the sheet bend. I believe that both are among the simplest knots, but that they are quite different : the bowline uses the collar, which is absent in the sheet bend, and the sheet bend uses the riding turn mechanism of the hitches ( that is, the one leg of the hitch pass over and the other passes under, so that the second one s squeezed by the first), a mechanism absent in the bowline. The loops that can be explained by the sheet bend indeed, are the Carrick loop, and the Angler s loop. The bowline is a Gleipnir with a collar, nothing more, nothing else. I wonder how you would explain the Gleipnir, with the sheet band mechanism... :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 24, 2011, 07:07:22 AM
Good Morning Xarax,

Are you a night owl or an early bird?

It is good to know that you are also attempting to identify the components of a working knot.  I agree, it is all too easy to be seduced by one's own and therefore myopic viewpoint - having access to others perspectives is critical to being able to consider flaws and weaknesses in one's view and so work towards a stronger, less flawed, understanding.

I have taken your arguments seriously and looked again at my perception of the Simple hitch component of the Bowline, and as seems to be the case with working knots, the closer one looks, the more complex the detail becomes...

First up, let me clarify a couple of points that I believe we agree on :-

1.  The Simple Hitch HAS to have the loaded line pinning the end against some 'static' surface by lateral pressure, in order to generate the anchor force which is then amplified by the turn around the 'static' object.  [Note: on closer inspection the Simple Hitch is far from simple and can in turn be broken down into its own components]

2.  That the Bowline CAN be configured such that the component I have called the ShC clearly has no 'hitch functionality at all and is functioning instead as a nipping turn - a la Gleipnir. [Note: in order to achieve this configuration, the bowline would be considered by many to be in the process of capsizing]

Having again looked in detail at the operational structure of the bowline I am convinced that my original assertion that this component is a ShC.  I will attempt to explain the reasons for my position to you, and I think this can best be done by a working example.

First up, make a bowline.  The following image from MotorboatsMonthly is I believe a good representation of what would generall be accepted as a working bowline.

(http://www.motorboatsmonthly.co.uk/imageBank/b/bowline-cover.jpg)

The image clearly shows the SP trapping and pinning the ShC end against the twin bight legs.  Proof that this is a working ShC can be demonstrated as I argued before - put 100% load across the SP and just the bight loop leg - the knot is a fully functioning Sheetbend.

But the proof does not stop there - now swing 100% load onto the ShC loop leg - the now dressed and set bowline will keep exactly the same conformance and the SP will continue to nip the ShC end tightly against the bight legs - granted, no frictional amplification is happening, because the ShC loop end is leaded to exactly the same load as the SP - but the point is, the structure is there and if the load in that leg of the loop dropped, then the component would function again as a ShC.

In reality, the loading across a bowline loop legs is rarely equal or static and for a large proportion of the time, the ShC is working to transfer load into the bight loop leg.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 24, 2011, 09:57:03 AM
(As) you know Derek, to
force square pegs into round holes

requires working day and night !   :) :)

I present you a gift, to test your theory ( that is, to try to falsify it, as we have to do with all  theories ). It is the, whimsically called, "Derek Smith 50% bowline" ( 50% refers to the loading of the eye leg of standing part and the eye leg of the bight). To my theory, it is a bowline 100%. No hitch present, legs of the collar 100% parallel to each other and to the standing end. WHERE s this SB part, where is this sheet bend hitch, or any hitch whatsoever ?
I admit that I am seduced by the Gleipnir mechanism, as you are seduced by the sheet bend mechanism. My opinion, of what is worth, is that the bowline is a closer relative to the Gleipnir, than to the Sheet bend. Your theory was valid before the advent of the Gleipnir, mine is valid afterwards...  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 24, 2011, 01:27:41 PM
Well, first up, I did not propose a theory - I offered a definition of a bowline in functional component terms - that is, the Bowline is a loopknot based on the SBCore.  In turn, the SBCore is a compound structure made from two components, each containing and contained by the other, those components being the Bight Component (BC) and the Simple Hitch Component (ShC).

However, to falsify this definition, all we would need to do would be to take a knot which was self evidently a Bowline and test it with the definition to see if it successfully identified the knot as the Bowline.

In the case of the delightful whimsy you have proposed as a test piece -

(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=5291;image)

Does it contain the BC  --  YES
Does it contain the ShC   --  NO  - it contains instead the Half Hitch Component (HhC)
Do these components contain and are they contained by each other  --  NO

Conclusion - by the offered definition, the whimsy is NOT a Bowline (nor do the additional components confer the status of Bowline Variant)

Does this falsify the proposed definition  - well, yes it would IF the proposed test piece were self evidently a Bowline.  One test for that might be - would the 'man in the street' identify it as a bowline?  I would suggest that most people would not, so we have failed to falsify my proposed definition with this test piece...

However, the subject of this post is "What defines a Bowline", so we have to come back to ask the question - "By what definition do you claim this to be a Bowline ?"

NB - as a whimsy, this construction is a doozer, but as a practical knot it falls apart the moment loop leg tension shifts even slightly from its defined 50%.  So as Bowlines are supposed to be the proverbial 'King of (practical) Knots', this little whimsy would have have quite a fight on its hands to be able to qualify...

Derek

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 24, 2011, 05:03:44 PM
it contains  the Half Hitch Component (HhC)

Where is this whimsy ?  :)

"By what definition do you claim this to be a Bowline ?"

By the definition given in (1), and quoted by agent smith at the first post of this thread ! I will repeat it, in a slightly different wording :
There are three, and only three elements that characterize a bowline, in relation to any other end of line loop:
1. The knot tied on the standing part s leg, should be topologically equivalent to the unknot, i.e., it could be completely untied with the removal of the rope segment after the eye leg of the bight. Any sailor will laugh with an end of line loop that is not completely untied like the bowline.  :)
2. This knot on the standing part should include one, at least, nipping loop, which secures the tail.
3. The rope segment after the eye leg of the bight should include one, at least, collar.

Based on that definition, the "bowline" presented above IS a bowline indeed ! ( Of course, following Dan Lehman, I have twisted the meaning of "collar" a little bit  :), as the U turn of the tail is around the standing part, indeed, but there is something else in between the nipping loop and the touching point of this "collar" with the standing part...I offered this example to you as an easy target, but you failed to shoot where you should, to the " Dan Lehman collar"... :))
My point was not answered from you, not now, not any time before. A hitch has its two legs highly asymmetrical, in looks as well as in function. The one is squeezing the other, so the one crosses the other, it passes above the other. The collar has its two legs symmetrical and parallel, they touch each other, of course, into the nipping loop, but they do not have to cross each other ! The two legs are squeezed by the nipping loop, they are symmetrical, in looks as well as in function. You want so much to explain the bowline in terms of the sheet bend, that you try to see the sheet bend hitch part in the bowline, too....Well. there is not such a structure there, and that s evident in the case of the bowline closest relative, the Gleipnir.

Does this falsify the proposed definition  - well, yes it would IF the proposed test piece were self evidently a Bowline.  One test for that might be - would the 'man in the street' identify it as a bowline?  I would suggest that most people would not, so we have failed to falsify my proposed definition with this test piece...

This test piece was an example of how a bowline structure can work, with the two legs of the collar parallel to each other and to the standing end. If it is not a bowline, it is not because the nipping loop does not hold as it holds in the case of the Gleipnir, i.e. with parallel legs going through it. It is because there is another structure, intervening between the "collar" and the nipping loop. You are right, of course, that most men in the street and the harbours will not identify this lousy loop as a bowline, but the only thing that this proves is that we should define the collar even more strictly - and not even more loosely, as Dan Lehman does ( and, as a result of this, he is driven to the indefensible position that the Carrick loop and the Angler s loop are bowlines...)
So, yes, let us define the collar in a way that does not include the collar-like stricture of this loop, to be in accordance with the tradition of the men in the streets and the harbours. But we must not confuse it with the hitch that exists in the sheet bend structure, because they are two completely different things. They are both very simple, elementary structures, so we have to be very careful to avoid any confusion between them, because if there is a confusion here, it goes all up to the top of the ladder, and we would not be able to analyse correctly the more complex knot structures.

By way, this structure was described by Korgan as a binder, in Reply # 73 (See attached pictures):  http://igkt.net/sm/index.php?topic=1870.60

1)  http://igkt.net/sm/index.php?topic=2897.msg17389#msg17389
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 25, 2011, 12:52:09 AM
There has been considerable talk of defining a Bwl by its nipping loop.

try to make a Bwl without its other key component - its bight loop...
[...]
Derek

Derek, you've not replied to my point here:

My quick answer to this is "Myrtle eyeknot" --the turNip
otherwise secured.  One can also consider the so-named
Eskimo bowline
--which collars an eye leg and ... <does what to?> the SPart.

What do you say to (how do you classify...) this (these)?

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 25, 2011, 05:55:16 PM
it contains  the Half Hitch Component (HhC)

Where is this whimsy ?  :)

Why - here in blue - of course...

(http://knotbox1.pbworks.com/w/file/fetch/43652123/HhC.jpg)

Just like here (http://www.2020site.org/knots/images/twohalfhitchesa.gif)

and here  (http://ems.leusd.k12.ca.us/modules/groups/homepagefiles/cms/568559/Image/Blakemore/Macrame/Half%20Hitch2.jpg)

and here (http://doit101.com/Knots/images/fig39.gif)

and ABoK 160 and 161 - - the very epitome of the 'Turn-nip'.

and...

Hoever, the exercise of pointing me at the Half hitch Component (HhC) has been fruitful, as it has had me thinking at the subtle, yet significant, differences between the ShC and the HhC.

The ShC has an unloaded end which is trapped by the loaded part against some other component, while in the HhC both parts are loaded and they bear against each other before turning into the nipping loop.

This then makes the component at issue within the Bowline a component which changes between a ShC and a HhC, due to the transient loading from 0% to !00% dependent upon the swing of the load / loop / SP.  However, unless wrongly tied, it is almost never a true HhC, and when correctly dressed, it is more correctly a ShC with partial end loading.

The Eskimo Bowline however, is an altogether different machine and I am going to think on it's components some more.  Anyone with thoughts, please dip in - more hands (minds) make light work.

Derek

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 25, 2011, 07:04:54 PM

Fig 39 shows a hitch, indeed, because the "two legs are highly asymmetrical, in looks as well as in function." The one leg is over the other,"it is squeezing the other, so the one crosses the other, it passes above the other." This is the elementary mechanism of "the riding turn". The riding turn is one of the five basic elements that we meet in practical knots.
In your second and third picture, you do not specify if the free end is loaded or not. If it is NOT loaded, we have half hitches indeed, because "When a bight has only one of its ends loaded, it is a hitch."  Now, if those legs ARE loaded as well as the others, ( i.e., both free ends of the knots are loaded ), the part of the knot you think it is hitch, it is not : it has both its legs loaded, so it is a nipping loop.
In ABoK#160 and #161, as well as in the test "bowline" I have submitted to you, and every bowline everywhere in the universe, we do not have hitches, we have nipping loops. Plain and simple ! I now understand how one can be blinded, even if he has the best intentions, as you do ! Read my lips :

1. The nipping loop is not a hitch. When a bight has both its ends loaded, and it is nipping a line that goes through it, it is a nipping loop. When a bight has only one of its ends loaded, it is a hitch. BIG, HUGE difference !  :)
2. ...A hitch has its second leg pressed under its first leg ( on some other tensioned rope strand or rigid surface).

Derek, please, do me a favour : Try to listen to me for one f...sentence ! The blue part you show is a nipping loop, not a hitch, because its two legs are both equally loaded, and they are symmetrical, in looks as well as in function.

The transient type of "hitch" you mention, the "Hhc", is not a hitch ! It is a nipping loop, where the legs, after they meet, they are in an elbow configuration to each other. So, the plane that is defined by the two legs of the nipping loop, just after they meet and leave, each towards another direction, is at an angle with the plane defined by the bight of the nipping loop.
I can understand a distinction beteen nipping loops, where this happens, and nipping loops where this does not   happen.
So we have nipping loops where
1. the free ends of the loaded bight leave the loop without been bent around each other, i.e. they leave, but remain in the plane defined by the bight,
and nipping loops where
2.  the free ends are crossed, they are in an elbow configuration with each other, they leave the loop after they are bent around each other, so they do not remain in the plane defined by the bight, but part to different directions.

This distinction is between two kinds of nipping loops, where both legs are equally loaded, not between a hitch and a nipping loop !
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 25, 2011, 09:13:06 PM
Derek, please, do me a favour : Try to listen to me

Um, before doing that,
about tying "a bowline" without the bight.
I'd like to advance on this issue (i.e., have definite
thoughts).

Quote
The blue part you show is a nipping loop, not a hitch,
because its two legs are both equally loaded,
and they are symmetrical, in looks as well as in function.

X., in general, you don't require "equally" (which of course
it isn't, in the base knot) --just a note here about the point.

Frankly, *I* do not regard this structure AS A ***KNOT***
--RATHER, it's a compound knotted structure.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 26, 2011, 02:06:13 AM
in general, you don't require "equally" (which of course it isn't, in the base knot)

Let us ignore, for a moment, the capstan effect on the collar bight U-turning around the standing part. Then, the two legs of the collar would be equally loaded, because it would have been as if we had a freely revolving pulley on the standing part, so no friction at all between the standing part and the collar. Now, consider that the nipping loop can move freely (walk) alongside the standing part, while keeping the two legs of the collar glued together, independently of its particular position. Will this nipping loop move (walk) alongside the standing part by its own, when the whole system is loaded and brought to an equilibrium ? Nooo. So, the two legs of the nipping loop are equally loaded, otherwise it would move towards the direction of the stronger pull.

*I* do not regard this structure AS A ***KNOT***--RATHER, it's a compound knotted structure.

If the trucker s hitch is not a knot, but a compound knotted structure, then yes, "I" agree.
I have thought of this artificially conceived "loop" only as a way to show that :

1. the two legs of a collar can be almost parallel to the standing end, and to each other.  This is happening in the case of the bowline and the Gleipnir. On the contrary, this is not happening, and can not happen, in the case of the Sheet band hitch mechanism, or any hitch whatsoever. So, the collar of the bowline can not be considered as a hitch. In the Sheet bend, we see segments of rope strands perpendicular to each other. On the contrary, in the Gleipnir or the bowline, we see only segments of ropes that are almost parallel to each other. As I have said,
"In a bowline, none of the two legs of the collar are in a right angle with a segment of the standing part, as it happens with the Sheet bend ! In fact, they are almost parallel with it, at the proximity of the nipping loop..."
"A hitch is defined by the asymmetry of its two legs : we can not have any hitch where the one leg is not passing over and the other is not passing under...as it happens in the sheet band. In a collar, the two legs are almost parallel to each other, as they enter and as they exit the nipping loop."
So, the bowline is a relative to the Gleipnir, not to the Sheet bend.

2.  the nipping loop of this 'loop" can be far away from the point where the collar touches the standing end, i.e. the U-turning point of the first leg of the collar around the standing end. This can not happen in the case of the Sheet bend hitch mechanism. So, the hitch mechanism of the Sheet bend can not be considered as a nipping loop, like the one we have in this "loop". And, because the nipping loop of this "loop" is just like the nipping loop we have in the bowline, the nipping loop of the bowline can not be considered as a Sheet bend hitch mechanism.

3 . the inclination of the plane of the nipping bight in the picture of the bowline, provided by Derel Smith in reply #60, is misleading. A bowline holds even if its collar is loose, and the U-turning point of the first leg of the collar is not very close to the nipping loop. In that case, the inclination of the bight of the bowline resembles the inclination of the bight of the test "loop", ( the "blue" segment). Both loops are nipping loops, and their nipping action is not depending on the specific inclination of the plane of the bight. Of course, as a nipping loop is more "twisted", its nipping power is diminished, because it is wasted by friction around the crossing point of its two legs. So, the less the inclination, the more the nipping power of the nipping loop on the two legs of the collar that pass through it. But this does not mean that the inclination is a necessary or a contributing factor to the nipping action, it is only a detrimental factor on a nipping action that already exists, because of the fact that both legs of the bight are loaded.. So, the inclination in the picture provided by Derek Smith, that forces the eye to be at a right angle / perpendicular to the standing part, is not a nessesary condition for the nipping action of the nipping loop. That inclination might have been the cause that misled Derek Smith in thinking that the nipping loop of the test "loop" is a hitch, when it is clarly a nipping loop, just like the nipping loop of the common bowline.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 26, 2011, 05:11:08 AM
in general, you don't require "equally" (which of course it isn't, in the base knot)

Let us ignore, for a moment, the capstan effect on the collar bight U-turning around the standing part. Then, the two legs of the collar would be equally loaded, because it would have been as if we had a freely revolving pulley on the standing part, so no friction at all between the standing part and the collar. Now, consider that the nipping loop can move freely (walk) alongside the standing part, while keeping the two legs of the collar glued together, independently of its particular position. Will this nipping loop move (walk) alongside the standing part by its own, when the whole system is loaded and brought to an equilibrium ? Nooo. So, the two legs of the nipping loop are equally loaded, otherwise it would move towards the direction of the stronger pull.

To be clear : I'm referring to the common bowline (#1010).

I'm not sure what you're saying here, but in actual physical terms,
the load on the eye legs --on either-- is 50% (roughly) which is
half of the 100% on the SPart; thus, the turNip is UNequally loaded
in its circle (just as in the sheet bend the end of the like-looking "hitch"
has zero loading).  In fact with HMPE, it has been observed to "walk"
--i.p., we have seen a video of the double bowline showing this
(amazing!) behavior, collapsing the eye to the pin of the test device.

Quote
*I* do not regard this structure AS A ***KNOT***--RATHER, it's a compound knotted structure.

If the trucker s hitch is not a knot, but a compound knotted structure, then yes, "I" agree.

Right.  And the venerable two half-hitches is compound, too
--the *knot* is the clove hitch of the line to itself, sealing
the hitching *structure*.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 26, 2011, 11:48:56 AM
in general, you don't require "equally" (which of course it isn't, in the base knot)
in actual physical terms, the load on the eye legs --on either-- is 50% (roughly) which is
half of the 100% on the SPart;

No. The load is half of the 100% on the (SPart + collar legs) !  :) The load at the eye leg of the standing part ( the one end of the nipping loop) is equal to the load on the standing end ( the other end of the nipping loop). That is why the nipping loop does not move up or down the test "'loop:"
Imagine that the knot is loaded and locked to a position. Then, replace the nipping loop s essential function by a drop of glue between the two legs of the collar ( that is why I have used the word "glue" in my previous reply, to facilitate one imagine this). So, now the two legs of the collar are glued together, so we have a stable collar loop and not a collar noose.  Now you do not need the nipping loop to squeeze the one leg with the other any more. In fact, you do not need ANY contact between the nipping loop and those two legs of the collar = you do not need ANY friction present between the nipping loop and those two legs of the collar. So, you can imagine now that the nipping loop can slide freely alongside the two legs of the collar indeed. ( The two legs of the collar, from the other side of the nipping loop, are the eye leg of the bight and the tail - and inversely, the eye leg of the bight and the tail, after they pass through the nipping loop, are the two legs of the collar ) If the nipping loop could slide freely alongside them, would it slide ? Nooo. The test "loop" would be stable and stationary, in every position of the nipping loop, up or down the standing part leg of the bight. It does not matter where exactly the nipping loop is located : The test "loop" will be stable and stationary, in every of those positions, and the loads on the two ends of the nipping loop will remain the same, ( 50% of the total load ), and equal.

(I am sure you would get it immediately, as soon as you manage to go through my imprecise, and perhaps erroneous, wording...)

I was talking about the test "loop", of course. What happens in the case of the common bowline ? There, just because we do not have the structure of the truckers hitch I have cunningly added/placed on the standing part - that prevents the collar bight to slide alongside the standing part, - the collar is stopped by the nipping loop volume. It can not slide downwards the standing part, because it can not pass the obstacle that the nipping loop presents. This will happen even in the case that, as discussed previously, the two legs of the collar were glued together, and there were no friction between them and the nipping loop. So, in the case of the common bowline, where we have glued the two legs of the collar and we have no friction between them and the nipping loop ( we could pass them through a slightly wider rigid cylinder ring, that keeps the nipping loop tensioned, but let them slide freely though it...), in that case, contrary with what happens in the case of the test "loop", the nipping loop IS squeezed by the collar bight, and is forced to move downwards the standing part : so it tries to "walk".  It can not, because of friction. So, the push of the collar bight on the nipping loop, that forces it to walk/slide downwards the standing part, would have happened even if there were no friction between the nipping loop and the two legs of the collar. That push forces the nipping loop to have a different orientation in the bowline, as shown by the Derek Smith picture, and in the test "loop". It has nothing to do with what Derek Smith describes, i.e, that the nipping loop it is a whimsy hitch. It IS a genuine nipping loop, regardless of its orientation, regardless of its proximity to the U-turning point of the collar bight. And it is a genuine nipping loop in the test "loop", as well as in the common bowline. I wonder how Derek Smith can see it as a - whimsy or not, "hitch"...

it has been observed to "walk"...we have seen a video of the double bowline showing this (amazing!) behaviour, collapsing the eye to the pin of the test device.

Well, not amazing to me... :) And if you see the test "loop", and then the bowline, the way I have described previously, you will understand that we should have expected this behaviour, and amazed if it would have NOT taken place ! And it does not take place very often, indeed, ( with most materials), because of high friction, that prevents the nipping loop to move freely and the eye loop to shrink to a point.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 26, 2011, 03:45:24 PM
There has been considerable talk of defining a Bwl by its nipping loop.

try to make a Bwl without its other key component - its bight loop...
[...]
Derek

Derek, you've not replied to my point here:

My quick answer to this is "Myrtle eyeknot" --the turNip
otherwise secured.  One can also consider the so-named
Eskimo bowline
--which collars an eye leg and ... <does what to?> the SPart.

What do you say to (how do you classify...) this (these)?

--dl*
====

Hi Dan,

My apologies for missing the second part of that post as being directed at myself.

First I would comment to that post that I wholly agree with and endorse your comment that tying method could leave a torsional 'memory' within the knot which could adversely influence its function.  Perhaps I should have said 'Should not', because any tying method which has created a detrimental 'memory' has created a substandard 'Variant' of the knot, (albeit at a level of subtlety very few would ever notice yet alone understand).

Moving on then to the first item of our post, I am struggling to understand our reply.

The proposal was that the Bwl only contained the ShC when it clearly comprises two components, the ShC and the BC.  My challenge was that if anyone was seriously suggesting that the BC was not part of the Bwl, to show me the Bwl as this single component knot - this is clearly ludicrous as a ShC by itself simply falls apart.

What you have done by proposing the Myrtle knot is to offer a knot where the second component - the BC, has been replaced by a Single Turn Component (RStC)['R' indicates a Right Handed Single Turn].

Of interest, the Myrtle is made from two identical enmeshed RStC's, but upon loading the SP / SP leg component stays a RStC, while the End / End leg takes up the form of a Simple Hitch Component (ShC)

Yes, you have shown me a knot with the ShC and without the BC, but are you seriously proposing that the Myrtle is a Bowline SIMPLY because it has the ShC in it? ?

As for the Eskimo - that is a more complex question that I am still working on...

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 26, 2011, 07:09:23 PM

Fig 39 shows a hitch, indeed, because the "two legs are highly asymmetrical, in looks as well as in function." The one leg is over the other,"it is squeezing the other, so the one crosses the other, it passes above the other." This is the elementary mechanism of "the riding turn". The riding turn is one of the five basic elements that we meet in practical knots.
In your second and third picture, you do not specify if the free end is loaded or not. If it is NOT loaded, we have half hitches indeed, because "When a bight has only one of its ends loaded, it is a hitch."  Now, if those legs ARE loaded as well as the others, ( i.e., both free ends of the knots are loaded ), the part of the knot you think it is hitch, it is not : it has both its legs loaded, so it is a nipping loop.
In ABoK#160 and #161, as well as in the test "bowline" I have submitted to you, and every bowline everywhere in the universe, we do not have hitches, we have nipping loops. Plain and simple ! I now understand how one can be blinded, even if he has the best intentions, as you do ! Read my lips :

1. The nipping loop is not a hitch. When a bight has both its ends loaded, and it is nipping a line that goes through it, it is a nipping loop. When a bight has only one of its ends loaded, it is a hitch. BIG, HUGE difference !  :)
2. ...A hitch has its second leg pressed under its first leg ( on some other tensioned rope strand or rigid surface).

snip...

Hi Xarax,

Well, yes, we can agree that I am confused...

I am confused that anyone can suggest that the Bowline's only significant component is the ShC.
I am confused that you would define the half hitch in Fig 39 as 'highly asymmetrical'
I am confused that you see in Fig 39 one leg "crossing and passing over the other", yet you don't see that this is true for both legs.
I am confused that you are calling "the riding turn" an elementary mechanism when its Force Vector Analysis is hugely complex.
I am confused that you question the loading of the end in the 'second and third pictures', when Fig 39 is clearly loaded  and is defined as a half hitch - someone else's definition, not mine.
I am confused that in ABoK#160 and #161 you claim them not to be hitches when Ashley states " the hitches are in the standing part."

But most of all, I am confused that you seem to be closing your mind to the fact that while a single turn (xStC) is a nipping loop and may not be a hitch, a Hitch by contrast is also (and I believe likely to always be) a nipping loop

What are we arguing about? The ShC functions as both a hitch and a nipping loop...  If it didn't then ring loading would end the life of a Bowline in short measure.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 26, 2011, 08:39:59 PM
I am afraid, Derek, that you are confused, indeed, and firing the one bullet right after the other will not save you ... :)
So, I will take your bullets, one by one :

1. ."I am confused that anyone can suggest that the Bowline's only significant component is the ShC"
1. Yes ! NOBODY can suggest that the Bowline's only significant component is the ShC (except you, of course !  :)). There is no hitch component in the bowline, neither the so-called "Shc", the hitch component of the Sheet bend, nor any other. The Bowline has two components : The main is the nipping loop, and the secondary is the collar. You try to explain the bowline in terms of the Sheet bend, in vein. The bowline is a Gleipnir with a collar, plain and simple .

2. "I am confused that you would define the half hitch in Fig 39 as 'highly asymmetrical'"
2. Yes ! The half hitch of Fig 39, and any other half hitch in the universe, is highly asymmetrical, because :
a. The second end is not loaded as the first
b. The one leg is over, or under, the other, the one leg squeezes the other on some rigid surface, or a tensioned line.

3."I am confused that you see in Fig 39 one leg "crossing and passing over the other", yet you don't see that this is true for both legs."
3. Yes ! The "first" leg is over the second, but the "second" leg is under the "first", by definition...  :) So, the two legs are not symmetrical, neither in looks, nor in function. The "first" squeezes the "second", but the "second" is squeezed by the "first", by definition. Asymmetry. The one is loaded, while the other is not. Asymmetry. The difference with the situation of two legs of the collar are so big, you can hide beneath it !   :)

4. "I am confused that you are calling "the riding turn" an elementary mechanism when its Force Vector Analysis is hugely complex."
4. Force Vector analysis in flexible materials ? Ok, publish your scientific essay, and I promise I will read it... Leaving this in the field of serious science, where it does belong, let us go to the "riding turn". I am afraid "I" am NOT obliged to publish a Nobel-prize winning essay on this, ( like you are, for the "Force Vector Anaysis" of the "xStC", "ShC", etc....), because, fortunately, everybody already knows and understands what a riding turn is.  :) The one segment of rope makesaturn around the line/pole, and passes over the other, remember ? Now, if it is the most elementary knot mechanism, or can further be reduced in an even more basic concept, this is debatable, of course, but do not try to mix the weaknesses of my theory with those of yours !  :) We are talking about your theory now, that considers the half hitch as "symmetrical" relatively to its two legs !

5. "I am confused that you question the loading of the end in the 'second and third pictures', when Fig 39 is clearly loaded  and is defined as a half hitch - someone else's definition, not mine."
5. Yes ! I was not supposed to know what the author of a sketch was meant to show. I have asked you to define it, and I have answered what happens in BOTH cases, the case where only the one free end of the knot was supposed to be loaded, and the case where both free ends were supposed to be loaded. Is that such a strong argument, that you feel you have to fire it towards me ? If it is, what can one say for the weak ones... :)

6. "I am confused that in ABoK#160 and #161 you claim them not to be hitches when Ashley states " the hitches are in the standing part.""
6. Yes ! The second structures of the ABoK#160 and ABoK#161, when and when only the one free end is loaded, they are hitches. When and where both ends are loaded, they are nipping loops. I have repeated this simple distinction a hundred times now, so you can not fail to listen it ! What is happening, Derek ? You are feeling so weak, that you are asking for help from your big brother ? You start citing the scripts  ?  :)

7. "But most of all, I am confused that you seem to be closing your mind to the fact that while a single turn (xStC) is a nipping loop and may not be a hitch, a Hitch by contrast is also (and I believe likely to always be) a nipping loop"
7. Yes! I am not going to split hairs to save face, as you do. A hitch is a hitch, and a nipping loop is a nipping loop. The fact that the hitch squeezes the pole or the rope around which is tied, does not make it a nipping loop, because it is highly asymmetric in its legs, the one leg being loaded, while the other is not. On the contrary, the nipping loop is symmetric in its legs, and both legs are equally loaded. Use any Sanskrit script you wish, like this "ShC" proto-indo-European one... :) Something should not be defined as a hitch and a nipping lop at the same time, otherwise our theories will serve less than astrology...We make a useful distinction and definition, even if there are similar mechanical functions in both our entities. I do not think that there is anybody that will fail to see those simple distinctions I have repeated again and again ( to use your style of the #1 argument... :))

What are we arguing about? The ShC functions as both a hitch and a nipping loop...

If that is so, why do you use this "ShC" entity ? If it is a Chimera, a Janus, a double-edged sword, forget t ! I will not help us explore, explain and define what is a bowline, because it can do anything !
On the contrary, the simple thing I have said is sufficient to classify the loops into bowlines and not-bowlines, whithout any such ambiguity.
1. The "collar" is a collar, it is not a hitch, neither a nipping loop. The bowline has one, at least collar, made by a bight of the eye leg of the bight end.
2. The "nipping loop" is a nipping loop, it is not a hitch, neither a collar. The bowline has one, at least, nipping loop on the standing part.
3. The (half)  hitch is a hitch, is not a nipping loop, neither a collar. The fact that it does constricts the pole or the line around which is tied, does not make it a nipping loop. The fact that it does make a U-turn around a pole or a line, does not make it a collar.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot4u on July 26, 2011, 09:40:53 PM
Is there a way to quantify things here?  This thread reminds me of freshman year Physics 101 in undergrad.  There was a lot of "talking" before the test.  At the top of that test, the professor gave us one arrogant formula:  F=ma.  The average score on that test was about 40%.  One unassuming student got a 100% and messed up the curve.  Suddenly, everybody wanted to pay attention to that kid.  The application of physics principles silenced a lot of the noise.  Likewise, we have got to find a way here to settle knot disputes with mathematics and scientific principles.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 26, 2011, 09:43:17 PM
I am confused that anyone can suggest that the Bowline's only significant component is the ShC.

Perhaps it should be taken that we are conjecturing what will be
held to constitute >> a *bowline* (-type knot) <<.
"The" bowline is most spare --loop + bight.  Now, I am happy to see
the family of like knots be those that bind with the former,
and which might be maintained/stabilized in a variety of
ways (so that the turNip has effect).

Beyond this, I look to something one might call a "false" or
"<some better adjective>" bowline when the continuation
from the turNip does not go directly into an eye leg
(e.g., it might collar the eye legs and feed back into the
knot (which would pique X.'s angst about the hitch vs. loop
distinction, though the continuation would have some tension)).

I don't see the bight-collar as defining (and if it were, it is quite
limiting to knots that I'd see --e.g., Myrtle-- as family members).

(It's not a matter of Right/Wrong here,
but of viability/usefulness of the definitions.)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 26, 2011, 10:57:29 PM
My Dear Xarax,

It was not a barage of bullets -

it was a plea for understanding - mine or yours or ours...

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 26, 2011, 11:24:34 PM
Is there a way to quantify things here?  This thread reminds me of freshman year Physics 101 in undergrad.  There was a lot of "talking" before the test.  At the top of that test, the professor gave us one arrogant formula:  F=ma.  The average score on that test was about 40%.  One unassuming student got a 100% and messed up the curve.  Suddenly, everybody wanted to pay attention to that kid.  The application of physics principles silenced a lot of the noise.  Likewise, we have got to find a way here to settle knot disputes with mathematics and scientific principles.

Hi K4u,

When I started to attempt to categorise knots based on their component parts, I had in mind my chemistry background, and naively thought that a knot could be described much like a molecule - by defining its component atoms and describing how they were arranged.  But over time I realised my error.  In chemistry, a Sodium atom is always a Sodium atom with exquisitely fixed properties, but in a knot, any component can morph and slew through an infinite continuum of forms - from an identifiable hitch, through a hitch / turn hybrid, through to a turn, and exhibit all those properties in turn and in part simultaneously by degrees.

Sadly, the more I study knots, the more I believe we are further than ever from a Science or Physics of knots - certainly, I do not possess a mind capable of taking us there.  But I do not give up hope that the scratchings and searching for understanding that we do today, will offer some chance in the future for some bright mind to make a breakthrough.  To that end all our confusion and mumblings may have some value.

On the particular issue at hand, there is little chance of moving forward, because the arguments proposed are simply opinions, and every one is valid although each might be at odds with the other.

Mark asked - "What defines a Bowline?" - I have answered that with my opinion, but that is all it is - a single persons opinion, my definition.  Someone else defines a Bowline differently and there you have an equally valid opinion and definition.

Unfortunately, the question has a very familiar counterpart - 'How long is a piece of string?'

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 26, 2011, 11:40:30 PM

(It's not a matter of Right/Wrong here,
but of viability/usefulness of the definitions.)

--dl*
====

Good point Dan, and it falls directly in line with the tight definition I have offered for a Bowline and a slightly less tight definition for Bowline Variants.  The usefulness then is that we describe a relatively small group of knots with similar attributes.  If by contrast we opt for a far more 'flexible' definition - then for example if we were to define a Bowline as a knot which has a nipping loop, then as this can be found in the vast majority of knots (by little or large), then just about everything becomes a 'Bowline' - and what is the usefulness in that?

Derek

NB  I have offered a definition from the 'components' perspective - but Mark did not make the question that narrow - are there any other aspects of what we perceive as a Bowline that can be added to the definition in order to confine the group size and hence improve usefulness.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 28, 2011, 12:39:54 AM

(It's not a matter of Right/Wrong here,
but of viability/usefulness of the definitions.)

--dl*
====

Good point Dan, and it falls directly in line with the tight definition I have offered for a Bowline and a slightly less tight definition for Bowline Variants.  The usefulness then is that we describe a relatively small group of knots with similar attributes.  If by contrast we opt for a far more 'flexible' definition - then for example if we were to define a Bowline as a knot which has a nipping loop, then as this can be found in the vast majority of knots (by little or large), then just about everything becomes a 'Bowline' - and what is the usefulness in that?

Derek, I think that by your criteria, the Fig.8-based knots become
*bowlines*, as their SPart's initial geometry fits your SBCore, and
at least the one with a simple bight-collar finish fills the bill.

In contrast, my & X.'s criterion of the turNip excludes these,
for the closure of that nipping loop in the 8 is more akin to the
locked-off end in the sheet bend  than the loaded-not-locked
continuation (into an eye leg).
.
.
.
But it might be that we need to see some considerable set of
prospects run through the various criteria to see what we think
of what emerges, in order to get a better feel for what we've
wrought in our criteria.

Now, there can be indicated infinities of things so classified
in some rather pointless extents (e.g., if the dbl. bwl is
a *bowline*, wouldn't a trpl.bwl be so --add one wrap?
... and when does that knot-building Add-A-Wrap ever cease
to qualify?  (It gets silly, though, nearly immediately!)
So, mere number needs some qualification.
Yes, though, one can get such a big field of *bowlines* that
one has then to subdivide into many sub-classes of *bowlines*;
but maybe this is yet preferable to a bunch of classes of the
first order which one might have some desire to see related
as kinfolk by some other means?

Xarax seem willing to regard the crossing-kinot-based knots
as nipping-loop bwl.s, while I want them distinct,
even though pointing out that that carrick loop can be seen
to reside in either camp --and in some fuzzing in-between state--
depending on how it's set.

Btw, you keep neglecting Mytle --your old flame, no less!-- :
where would you classify that?  (I call it *bowline*; X. will find
it short of a "proper collar".)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 28, 2011, 01:35:25 AM
Now, there can be indicated infinities of things so classified in some rather pointless extents (e.g., if the dbl. bwl is
a *bowline*, wouldn't a trl.bwl be so --add one wrap?... and when does that knot-building Add-A-Wrap ever cease
to qualify?  (It gets silly, though, nearly immediately!)
So, mere number needs some qualification.

All families of knots are infinite, if you do not put a limit on the number of tucks, or the number of crossings. The family of bowlines is not infinite, if we consider only the practical knots. In that sense, if we put a reasonable upper limit on the number of nipping loops and the number of collars of a bowline ( say two, for example ), the number of practical knots that belong to the bowline family remains big, but finite...

... seem willing to regard the crossing-knot-based knots as nipping-loop bwl.s, while I want them distinct

No, I am not willing, I am obliged to do so...I would love to throw them out, but I can not see how, without throwing out the baby, too : the complex, "improved" TIB nipping loops, as the Pretzel, the Constrictor/Transom, ( and their "inverted" forms ), in short, any structure tied on the standing part, topologically equivalent to the unknot, that can efficiently nip/constrict/secure the tail - with the help of a "proper" collar  :), of course ! I want a better definition of the nipping loop, which would possibly exclude the ugly "crossing knot", ( and the Karash loop that is based on it ), but, for the time being, I have not any...However, I would not go as far as Derek Smith, and try to analyse further the nipping loop itself, in its various similar forms, into some even more elementary parts, that might have somethng common with similar parts of a particular hitch, or not. The nipping loop is no hitch, even if the hitch, too, constricts the pole or the line around which it is tied.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 29, 2011, 06:48:19 AM

... seem willing to regard the crossing-knot-based knots as nipping-loop bwl.s, while I want them distinct

No, I am not willing, I am obliged to do so...
I would love to throw them out,
but I can not see how, without throwing out the baby, too :
the complex, "improved" TIB nipping loops, as the Pretzel, the Constrictor/Transom,
( and their "inverted" forms ), in short, any structure tied on the standing part,
topologically equivalent to the unknot, that can efficiently nip/constrict/secure the tail - ...

Hmmm, I see no reason to make the definer "UNknot";
leave as the turNip --a requirement that the loop feed
into the eye, to be directly tensioned thus.  The crossing knot
violates this with its turn around the SPart --*indirect*.

(But I think that I've been too casual on my considerations
of the Dbl.bwl, water bwl, and so on, where the turNip
feeds something else, not the eye; it might be that one
must allow more than the turNip --some like structures.)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 29, 2011, 08:30:42 AM
the loop feed into the eye, to be directly tensioned
The crossing knot violates this with its turn around the SPart

But so does the nipping loop in the case of the Eskimo bowine ! You don t expect me to throw out this baby, do you ?  :)
I believe that the (first)collar should be tied around the standing part, on whatever side of the nipping loop it can. : If it had happened to the rabbit / working end, to enter into the nipping loop from the one particular side, it can only make a U-turn around the standing part and go back into its nest by a collar around the one particular end of the nipping loop. If it had happened to enter into the nipping loop from the other side, it can only make a U-turn around the standing part and go back into its nest by a collar around the other end of the nipping loop. The nipping loop is there, on the standing part, waiting for the rabbit to pass through it from whatever side, make a U-turn around whatever end/leg of the nipping loop it can, and return into its nest. If the rabbit happens to enter from the one particular side of the nipping loop and exit from the other side, it can only go around the one particular end/leg of the nipping loop. If it happens to do the opposite, it can only go around the other end/leg of the nipping loop. I am not willing to sacrifice this symmetry of the rabbit s path, in relation to the nipping loop, AND throw the Eskimo bowline baby out, with the dirty water, the "crossing knot" and the Karash loop.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DDK on July 29, 2011, 05:58:23 PM
What defines a bowline?  To this point, convention which has led some fixed loops to be labeled bowline and others not.  When a formal definition is desired and sought by committee, it resembles this thread.  :)

I might point out that much of what has been proposed would appear to invite substantial subjectivity. The elimination of this subjectivity would be objectionable to most of us.  For example, one way to eliminate subjectivity would be to consider each fixed single loop as a looped version of a knot or bend and all double loops as variations of their single loop counterparts.  Thus, the bowline, dbl. bowline, and Eskimo bowline are bowlines as they are Sheetbend Loops.  The Karash single loop and its variations are Karash Sheetbend Loops, and so, are not bowlines.

I did not say you were going to like this.  I was merely pointing out what the elimination of subjectivity is going to look like.  Otherwise, the spinning of wheels does have its benefits as a number of interesting topics and ideas have been discussed.

DDK
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 29, 2011, 06:29:56 PM
...one way to eliminate subjectivity would be to consider each fixed single loop as a looped version of a knot or bend

If THAT has anything to do with "objectivity", no wonder what "subjectivity" looks like !  :)
The end of line loops are loaded entirely differently than their "corresponding" bends. So, the bowline has nothing in common with the Sheet bend, and, of course, it is not a "Sheetbend loop" ! Not even Derek Smith said anything like this...
I prefer a live camel from a dead horse... :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 30, 2011, 02:42:00 AM
I might point out that much of what has been proposed would appear to invite substantial subjectivity.
The elimination of this subjectivity would be objectionable to most of us.

Not sure I follow this.  What we're trying to do is
to be objective --to establish a rule in the face of what
has been somewhat haphazard naming.

Quote
Thus, the bowline, dbl. bowline, and Eskimo bowline are bowlines
as they are Sheetbend Loops.

Well, the 3rd is a *reverse* sheet bend --yes, it can be seen
as having in a sense the same formal shape, but on
setting it is quite different (as Xarax remarks, more of a
crossing knot-based eyeknot, not with a turNip base).

And, so, yes, Xarax, I do expect the Eskimo Bwl. to be thrown
out of the *bowline* set.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DDK on July 30, 2011, 05:05:20 AM
Both xarax and d.l. picked up immediately on several of the objectionable sacrifices that an unambiguous and non-subjective nomenclature of fixed loops might suffer from.  Namely, for the example that I gave, the ignoring of the loading of the ends, knot element mechanics and functionality (and likely a few others).  This was, in fact, one of my points.  Will there always be a slippery slope without accepting some objectionable (to some) limitations?  I will be pleased to find it not true as it would be like having our cake and eat it too.

DDK
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 30, 2011, 05:16:34 AM
I do expect the Eskimo Bwl. to be thrown out of the *bowline* set.

You miss the symmetry argument that I have tried to explain in Reply#82...and according to which, we should define the bowline independently of the side of entrance of the eye leg of the bight into the nipping loop. Using the "direct / indirect" argument about the nipping loop legs and their relation to the eye, you will get rid of a few pesky "crossing knot"-based loops, ( like the Karash loop ), that is true, but you will also lose the Eskimo bowline...and I think that you will do it, because that is what you had in mind right from the beginning ! :) The Karash loop was just a minor, secondary target, your true purpose was always  the declassification of the "anti-bowline" Eskimo bowline....
It would be more general and accurate if one makes a distinction between (+) and (-) bowlines, for example ( or whatever pair of antonyms one chooses). I believe that, from time immemorial, people tied bowlines in both ways, just preferred the common bowline, when the eye legs were close to be parallel ( in loops tied around small diameter objects, where the knot s nub is far from the object ), and preferred  the Eskimo bowline, when the eye legs were close to be aligned ( in loops tied around large diameter objects, where the knot s nub is close to the object). There is no essential difference : the collar , an extension of the eye leg of the bight, helps the nipping loop secure the tail, and makes a U turn around the line that is more aligned with the eye leg of the bight. If the loop is elongated, because it is tied around a small diameter object, the collar makes a U turn around the segment of the standing part outside the bight. If, on the other hand, the loop is round, because it encircles a large diameter object, the eye leg of the bight is more aligned with the segment of the standing part inside the bight, so it is natural to the collar to make a  U turn around this segment of the standing part, i.e. around the eye leg of the standing part.
The main victim of a restricted classification, that fails to take into proper account this symmetry I am talking about, will not be the Eskimo bowline itself : The main victim will be the objectivity DDK is talkng about : the accuracy of the description of the common bowline, and the generality of its definition...
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 30, 2011, 08:07:52 AM
Excluding the Eskimo Bwl. from it's set requires you to exclude the Offset OH from it's set likewise. What 's needed is a Hierarchy of Criteria by which knots are classified according to. Say something like; Working Form, Topology, Loading Profile, Attributes, Use, Existing Name, etc. Each criteria would serve to differentiate one knot from another and in/exclude then from a particular family of knots.

alpineer
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: [Inkanyezi] gone on July 30, 2011, 11:10:41 AM
I don't see a real need to classify linguistically in the same way as structurally. Language doesn't follow strict rules, so we may well exclude the Eskimo Bowline from the Bowline family of knots, but still call it a bowline, and the same might go for the Bowline tied in the bight, if they don't conform to any more or less random rule that we set up as a definition for the family of knots.

OTOH those knots may be included if we follow a different set of rules. I have no problem to see the Eskimo Bowline as part of the bowline family, when we consider the likeness, its way of tying and the behaviour of the knot when load is applied upon only two of its parts. Most of these knots might behave as a sheet bend when loaded at either one bight leg and the standing part or between the two legs of the loop even if many of them in their working form and intended load will incorporate a nipping turn resembling the Gleipnir. At least one collar around a leg or the standing part is a distinctive feature, but we should not disregard the possibility that the bight might not by its own means embrace its relevant part, but is attached with a toggle.

Of course my stance in part might be explained from the fact that I use several languages on a daily basis, and if a classification is done, I feel an urge to apply it to all languages, which makes it a lot more difficult to apply strict rules linguistically, while structurally it might be a bit simpler to classify knots. Still I would try not to exclude knots that as the Eskimo Bowline display so many likenesses with other knots of the family, while it is easier for me to think of the Myrtle as something else. Either way, I don't think classification is a "Practical Knots" issue, but more one of the theoretical kind.

I think disregarding the Gleipnir-like nipping turn from the family criteria, in favour of a more relaxed view based on what things look like on the surface and how they are made, is easy to live with. Structurally they may differ a lot, but that is what we should expect from different knots made for different purposes, even though they share family features.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 30, 2011, 01:23:18 PM
Most of these knots might behave as a sheet bend when loaded at either one bight leg and the standing part, or between the two legs of the loop

Yes, but, most of the times, ( say, 99.99% :)), they are NOT loaded like this ! They are three-loaded-ends, single or double, LOOPS, not two-loaded-ends BENDS ! Big, Huge difference !
You can easily see how irrelevant/wrong is that phrase, if you invert it...  :)
"The Sheet bend might behave as a bowline, when loaded at both legs of the one link ."  :'(
The Sheet bend is a bend, all  the times, ( .i.e., 100.00 %  :)), a knot connecting TWO lines, where ONE and - and not but one - end of each link is loaded. !
( I have been recently studying the "inverse" knots of the the three Shakehands bends, where we load the ends that were used to be the tails of the "parent" knots. Although the number of ends that is loaded remains the same, the knots are transformed, in looks as well as in function, completely, I would say miraculously ! )

The only relevant/correct phrase would be :
"If we load three (particular) ends of a Sheet bend, we get the bowline structure."
So, what ?  :)
The Sheet bend - bowline false correlation was initiated by some Ashley comments, and Derek Smith elevated it into a new theory. People are seduced into this theory by the appearance of a one-leg loaded bowline, like the one shown in the picture of reply# 60. However, appearances are often misleading, especially if they are meant to "to force square pegs into round holes "   :). The inclination of the nipping loop of the bowline is due to the pressure of the collar. So, the one leg ot the eye, the eye leg of the standing part, is squeezed in between the collar and the nipping loop s inclined plane, and it looks like it is at right angle/perpendicular to the standing end ! Legs at right angle, perpendicular to each other resemble the structure of a hitch, a misleading, confusing sign had made Derek Smith believe the obviously wrong thing, that the bowline is related to the Sheet bend... Well, my eyes, too, can see the evidently similar picture, but my mind can not fail to see the entirely different essense, due to the entirely different loading and force distribution...and, I am afraid that "The mind sees and the mind hears".

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 30, 2011, 01:44:02 PM
I don't see a real need to classify linguistically in the same way as structurally. Language doesn't follow strict rules, so we may well exclude the Eskimo Bowline from the Bowline family of knots, but still call it a bowline, and the same might go for the Bowline tied in the bight, if they don't conform to any more or less random rule that we set up as a definition for the family of knots.

OTOH those knots may be included if we follow a different set of rules. I have no problem to see the Eskimo Bowline as part of the bowline family, when we consider the likeness, its way of tying and the behaviour of the knot when load is applied upon only two of its parts. Most of these knots might behave as a sheet bend when loaded at either one bight leg and the standing part or between the two legs of the loop even if many of them in their working form and intended load will incorporate a nipping turn resembling the Gleipnir. At least one collar around a leg or the standing part is a distinctive feature, but we should not disregard the possibility that the bight might not by its own means embrace its relevant part, but is attached with a toggle.

Of course my stance in part might be explained from the fact that I use several languages on a daily basis, and if a classification is done, I feel an urge to apply it to all languages, which makes it a lot more difficult to apply strict rules linguistically, while structurally it might be a bit simpler to classify knots. Still I would try not to exclude knots that as the Eskimo Bowline display so many likenesses with other knots of the family, while it is easier for me to think of the Myrtle as something else. Either way, I don't think classification is a "Practical Knots" issue, but more one of the theoretical kind.

I think disregarding the Gleipnir-like nipping turn from the family criteria, in favour of a more relaxed view based on what things look like on the surface and how they are made, is easy to live with. Structurally they may differ a lot, but that is what we should expect from different knots made for different purposes, even though they share family features.

Now this is the kind of level headed, even handed and measured dialog we need more of. Thank you Inkanyezi.

alpineer
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 30, 2011, 02:09:37 PM
I think disregarding the ...nipping turn from the family criteria, in favour of a more relaxed view based on what things look like on the surface... is easy to live with.

It is always "easy" to live with "more relaxed views" of things, of how things "look like", "on the surface"...Perhaps fortunately, most people live like this...
However, if one s purpose is not to live easily, but to live truly, and to understand things underneath the "surface", to discover the essence of things often hidden behind misleading appearances, I am afraid he has to try and search a little more...
I hope that the much wanted "level headed, even handed and measured dialogue", should not dictate us to accept a "level headed, even handed and measured"  truth, because there is not such a thing ! Fortunately, in science, a thing is either true or false !  :)
The bowline is not a Sheet bend, and the bowline structure is more related to a "Gleipnir with a collar"  than to the Sheet bend.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: [Inkanyezi] gone on July 30, 2011, 09:08:58 PM

The bowline is not a Sheet bend, and the bowline structure is more related to a "Gleipnir with a collar"  than to the Sheet bend.

Maybe  I should remind you that I was the first one to point that out?

This is not a discussion of what is truth about a Bowline, but I see it as a tentative to do some classification of a group of knots that are supposed to belong to a family, which should be further defined. In such classification it may have some merit to be very strict, but there might also be reasons for a more lax attitude. After all, whether science or not, the issue is not falsifying any knot that is named Bowline, but rather trying to find common treats if we find it fruitful to classify a certain order of knots as belonging to the bowline family.

In such an effort, I would find it natural to include the Eskimo Bowline, in spite of its odd orientation and structural difference compared to other bowlines. It is an anomaly if we consider the nipping turn to be crucial and if we regard it essential that the finishing U-turn, the collar, should embrace the standing part. Nevertheless, it shares many features with the proper Bowline, and it is a useful knot. By excluding it from the "family" on grounds that it has no TurNip, also mutiple turn bowlines should be excluded, and we get into a maze of classifications that I find unneeded. Someone else might feel a need for it, but I do not.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 30, 2011, 10:26:21 PM
Maybe  I should remind you that I was the first one to point that out?

Thank you, but, as you should have known by now, questions about priorities are not my cup of tea... :) I just repeated what I keep saying to Derek Smith from my first reply. I am glad you have the same view, because I respect your knowledge about knotting, which is, evidently, far more extended than mine.

This is not a discussion of what is truth about a Bowline...

Well, it was supposed to be...  :) Read the heading of the thread ! The questions about other members, or not, of the bowline group, were only brought into the discussion afterwards...

... I would find it natural to include the Eskimo Bowline, in spite of its odd orientation and structural difference compared to other bowlines.

More than simply "natural" : true ! Some things might appear "natural", and be false, but if we follow the simple definition of  bowlines I have tried to offer, the Eskimo bowline can not but be included in the bowline group. Its "structure, characteristics, topology" oblige us to clasfy it in the same group as the common bowline. If, on the other hand, we insist to specify the side of the nipping loop the tail enters into, or exits from, and/or the leg of the nipping loop that serves as the tree for our U-turning rabbit, we can eliminate the Eskimo bowline from the bowline group (which might be an unwanted thing to do), but also we can eliminate other "crossing-knot" based loops, as this !@#$%^&*()_overestimated Karash bowline ( which is a thing I would love to be able to do, indeed ! ) It is an anomaly if we consider the nipping turn to be crucial and if we regard it essential that the finishing U-turn, the collar, should embrace the standing part. ...from either side of the nipping loop ". Why ? Both characteristics are necessary. The (first, main) nipping loop should be tied on the eye leg of the standing part, because its function is to secure the tail, which is on the eye leg of the bight. And the collar is a just a clever means of the tail, to make this job of the nipping loop easier. So, the collar should embrace the standing part. Why is it an anomaly ? If there were a nipping loop and/or a collar only elsewhere, I would nt consider this end-o-line loop a member of the bowline family. The collar is not any U turn of a segment of the rope...The collar is a U turn of the tail, it is a mechanism of the tail, a means of the tail to be secured easier by the nipping loop.... Also, the nipping loop is not any 360 degrees turn of a segment of a rope...A nipping loop is a 360 degrees bight around the tail, it is a constricting mechanism that nips the tail, a mechanism to secure the tail. It is absurd to talk about collars on the standing part, and nipping loops on the working end / tail ! Title: Re: What defines a Bowline? - structure, characteristics, topology Post by: Dan_Lehman on July 31, 2011, 05:50:57 AM Excluding the Eskimo Bwl. from it's set requires you to exclude the Offset OH from it's set likewise. Huh? (He gasps, w/o even effort at decorum.) I don't understand what you're saying re the latter knot. :) Title: Re: What defines a Bowline? - structure, characteristics, topology Post by: Dan_Lehman on July 31, 2011, 06:37:53 AM Fortunately, in science, a thing is either true or false ! :) How's that work for you with quantum mechanics? Didn't the Law of the Excluded Muddle get broken there? (And, actually, there are reams of thoughts on what makes "true" ... .) Quote The bowline is not a Sheet bend, and the bowline structure is more related to a "Gleipnir with a collar" ... It is you who see necessity in some collar, not I (who even sees more of collaring than you do!). My base is the turNip (not the Gleipnir, which is a structure incorporating that). On the question of the eskimo bowline, I'm going to straddle the middle, or be on both sides, as with that carrick loop --can be either, depending upon the setting. I think that it might here be more unnatural to get the crossing-knot form, given any casualness in setting, and elastic rope. But it has some potential to go further away from the crossing-knot geometry, past the loop into a spiral --something I see "anti-bowlines" vulnerable to, with their tail entering on the opposite side of the loop (making stabilization of the turNip more a challenge). ack! Further, to X. : "SPart is that bring 100% tension into the knot; what runs from this into the eye --an eye leg-- is just that (eye leg), not SPart any more. So your bit about some "symmetry ..." with collaring going either direction loses me. But then I don't need any collar as such, so I don't really care. To Ink., multiple-turns don't worry me, as the turNip is but the start of a coil of constriction; but the clove base would be tossed, or make some kind of sub-class (and it is partly a confusion of history itself --the additional loop has been located at some remove from the first, in some references, and it's unclear what was in fact used). Keep in mind, also, that we are here focused on #1010 and seeing how it might be generalized/defined so as to guide us on a formal *bowline* classification: what might appear to be something that should be brought in under this tent from this focus could well see stronger ties to some other start point, and a big tent here might simply result in a fight over where things go when other knots come to get their essences defined --and having things in several classes at once doesn't sound terribly helpful, either. There IS such a thing as a crossing knot, and one can build up a set of eye knots with it as a base --and it will lay a claim on the eskimo bwl. right away. --dl* ==== Title: Re: What defines a Bowline? - structure, characteristics, topology Post by: Dan_Lehman on July 31, 2011, 06:45:12 AM Both xarax and d.l. picked up immediately on several of the objectionable sacrifices that an unambiguous and non-subjective nomenclature of fixed loops might suffer from. Namely, for the example that I gave, the ignoring of the loading of the ends, ... I'm still struggling to see how I'm the one being UNobjective? Loading is the essence of a *knot*; I think you're aiming at something logically *prior* that, which we might call a "tangle" --but which I've had trouble seeing as really being free of loading or anticipating loading. In any case, I don't find the consideration of loading to sacrifice objectivity. (But there are certainly fuzzy boundaries, as have been noted, in shifting geometries coming with vagaries of dressing.) --dl* ==== Title: Re: What defines a Bowline? - structure, characteristics, topology Post by: xarax on July 31, 2011, 11:28:48 AM It is you who see necessity in some collar, not I(who even sees more of collaring than you do!). Yes, that is funny ! :) I believe that the "proper" collar is an indispensable element of the bowline (albeit only the secondary one, after the nipping loop). You do not believe this, but you are ready to accept a more relaxed definition of the collar, and see collars where I do not...I explain it as following : I pay much attention to the collar, the particular "proper" collar of the bowline, where the second leg, after its U turn around some segment of the standing part, re-turns into the same opening it exited from, now pointing to the opposite direction. Paying much attention to this "restricted" kind of collars, it is natural and expected to distinguish the "proper" forms from the "generalized" forms you have in mind, and use this restricted definition to eliminate other loops from the bowline group ( like the ABoK#1033, the Angler s loop, the Myrtle...) At the end of the day, incorporating the "proper" collar into the essential elements of the bowline group, leaves us with much fewer "bowlines" than you are ready to accept, and, given the plethora of them we already have, that is a good thing, I believe ! :) You are left in an indifensible position, to deseparetely try define as "bowlines" many knots that nobody will ever name like this, believe me. You might succeed to reduce their number a little bit, by the clever "direct / indirect " distinction of the feed of the nipping loop tension into the eye, but your net result will still be far greater than wanted ! My base is the turNip (not the Gleipnir, Mine too ! I do not say that the Gleipnir is an element of practical knots, I say that it is the purest knot that incorporates the "basic element" of the practical knots that is the nipping loop. I say that "the Bowline is related to the Gleipnir more than to the Sheet bend", because we relate knots to knots, not knots to basic elements of them. We explain knots by analysing them into basic elements, and the basic element of the Gleipnir is the nipping loop, exactly as it happens in the bowline. I think we are on the same page in this, for once... On the question of the eskimo bowline, I'm going to straddle the middle, or be on both sides, as with that carrick loop-can be either, depending upon the setting. Well, to walk on a tensioned rope is a difficult exercise...Good luck ! :) "SPart is that brings 100% tension into the knot; what runs from this into the eye --an eye leg-- is just that (eye leg), not SPart any more. So your bit about some "symmetry ..." with collaring going either direction loses me. Just a minute ! I said about THE TEST LOOP that I submitted to Derek Smith, that the standing part there brings 50% of total tension into the eye ! ( The other 50% is brought by the combined presence of the two legs of the collar.) And I was talking about the Standing part AFTER the other structure of the compound knot, the mid line TIB loop I had used - to show that the two legs of the collar can be almost parallel to each other and to the standing art, yet the collar works. This was made in an effort to offer a counter-example to Derek Smith, who sees, in the one-sided loaded bowline, segments of rope perpendicular to each other, and so he relates the bowline to a hitch, the hitch element of the Sheet bend.The two legs of a collar can be almost parallel to each other, and this collar works : when the two legs of a hitch are parallel to each other, this hitch doen not work ! I characterize as "standing part" the segments of the rope before, within, and after the nipping loop, and also the eye leg of the standing part. I do not characterize as standing part the "rest of the knot", that is : the eye leg of the bight, the first leg of the collar, the second leg of the collar, and the tail - i.e. the segments of the rope that come "after" the standing part. According to this characterization, the lowest point of the bight separates the standing part from the rest of the knot : The sailor should tie the topologically-equivalent-to-the-unknot structure on the former, and pass through it the working end / tail of the later. So, when he unties the bowline, i.e. pulls the tail out of this unknot, the standing part is left with no knotted structure on it, and that happens even before the rope gets out of the ring or the bollard- a necessary requirement for the mooring line. What is your difficulty with the symmetry argument ? It is a local symmetry, of course, not a symmetry of the whole knot ! Locally, in the proximity of the nipping loop, the segment of the rope is, from the one hand, the standing part end, and, from the other, the eye leg of the bight that belongs to the standing part. When the rabbit reaches the nipping loop, it does not have to think/choose, in advance, from which end it will pass through : And, after it passes through, it does not have to think/choose around which particular end of this nipping loop - around which segment of the standing part - it will make its U turn. It just makes the U turn around the only leg it can ( Otherwise, it will form a loop that will slip through the nipping loop, so the rabbit will be eaten by the fox, and it will not survive to describe to us its definition of the bowline... :)) I think that the bowline should be defined independently /without any reference to the particular side the working end / tail it passes through, ( be it as in the common bowline, or as in the Eskimo bowline ), and the collar should be defined independently / without any reference to the particular side the working end / tail passes around the standing part segment of rope, in the vicinity of the nipping loop. See the picture of Reply# 82 : No indication which is the "front" or the "back" side of the nipping loop, no indication of which is the segment of the standing part inside the eye ( "after" the nipping loop) and which is the segment of the standing part outside the eye ( "before" the nipping loop). So, the bowline mechanism is defined with the fewer possible references to particular thoughts/choises of the rabbit, and only with references to the locally, symmetrically positioned knot structures in front of it, where the rabbit has no choice at all - if it does not wishes to be eaten by the fox, of course, i.e. if it wishes to form a collar loop that can not bedeformed/untied by a pull of the eye leg of the bight. P. S. Fortunately, in science, a thing is either true or false ! :) How's that work for you with quantum mechanics? Didn't the Law of the Excluded Middle get broken there? (And, actually, there are reams of thoughts on what makes "true" ... .) Oh, my dear Dan Lehman, your debt to me is now reduced by 100 worthless US dollars ( to -2650$...) , just because you have mentioned QM, Excluded Middle, and all that, however erroneously you interpret them !  :) ( US congress will not solve its debt problem with this gain of yours, but it is a positive sign nevertheless...) If you keep going like this, you will be free of debt in just a few dozens of dozens years !
I would LOVE to talk about those things, because I have spent 35 years of my life, into the mud, studying them !  :) When you were studying and tying knots, I was trying to un-tangle the various interpretations of QM, Brouwer s constructivist/intuitionstic interpretation of mathematics in relation to the Platonic/realistic one, and all that...However, I leave you to be beaten by roo this time  :), because those things have no relation to practical knots whatsoever. Truth, that beloved and betrayed goddess, has indeed, and it is that truth we are here to unveil, I believe. ( I would be glad to discuss any questions about interpretations of QM and Constructivist/Intuitionistic logic and mathematics, through e-mail).
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: [Inkanyezi] gone on July 31, 2011, 11:31:31 AM
Maybe  I should remind you that I was the first one to point that out?

Thank you, but, as you should have known by now, questions about priorities are not my cup of tea.

Neither is it mine, and mine is also not an endless quibble about unimportant matters. If you were not focussed upon quibble, you might have understood that my remark was not about priorities.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: [Inkanyezi] gone on July 31, 2011, 04:45:41 PM
Xarax, I'll try to write slowly in hope that you might understand:

I told you that I pointed out the turNip feature first, in order to remind you that I am not unaware of its importance in the Bowline. It is you, nobody else, who starts a "mine is bigger than yours" battle. Please chill a bit, it is not that important. You may choose any definition you want for your bowlines, I really don't mind at all.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DDK on July 31, 2011, 05:57:18 PM
Both xarax and d.l. picked up immediately on several of the objectionable sacrifices that
an unambiguous and non-subjective nomenclature of fixed loops
might suffer from.  Namely, for the example that I gave, the ignoring of the loading of the ends,
...
. . .  I'm still struggling to see how I'm the one being UNobjective?  . . .

--dl*
====

Well, let's first be clear that my comment was not singling you or xarax out as being unobjective.  My comment was that you had easily found how deficient to most an unambiguous and non-subjective (clear boundaries) definition could be.  By the way, I do not see objective = good and subjective = bad in our present circumstances.

I mean, we are talking about nomenclature here, so, there are going to be choices to be made regarding Hierarchy of Criteria as mentioned by alpineer* and from there boundaries (likely fuzzy) to be set.  I might ask if the Hierarchy of Criteria* is obvious to all (apparently not) and before one does that, is it obvious to all to whom this definition should be viable/useful?

DDK

* http://igkt.net/sm/index.php?topic=3233.msg19791#msg19791 (http://igkt.net/sm/index.php?topic=3233.msg19791#msg19791)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 31, 2011, 06:05:24 PM
any definition you want for your bowlines

"My" bowlines ? ? "Yours" are different/bigger ?  :) :)

I really don't mind at all.

Well, I can reply to this evaluation of my efforts to try to understand what the bowline is - not "my" bowline, not even yours... :)- by the infamous Knot4u dictum : "I think I can live with this..."
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 31, 2011, 06:19:01 PM
snip...

This is not a discussion of what is truth about a Bowline, but I see it as a tentative to do some classification of a group of knots that are supposed to belong to a family, which should be further defined. In such classification it may have some merit to be very strict, but there might also be reasons for a more lax attitude. After all, whether science or not, the issue is not falsifying any knot that is named Bowline, but rather trying to find common treats if we find it fruitful to classify a certain order of knots as belonging to the bowline family.

snip...

snip...

sacrifice objectivity.
(But there are certainly fuzzy boundaries, as have been noted,
in shifting geometries coming with vagaries of dressing.)

--dl*
====

"What defines a Bowline?"

At one extreme we have a single knot - #1010 (in the left hand and right hand variants)

(http://www.motorboatsmonthly.co.uk/imageBank/b/bowline-cover.jpg)www.motorboatsmonthly.co.uk

"ABoK 1010. The BOWLINE, BOWLING, or BOLIN KNOT, sometimes called
BOWLING's KNOT. The name is derived from bow line, a rope that
holds the weather leech of a square sail forward and prevents the
sail from being taken aback. As the line or rope that provided the
knot is no longer in use, the BOWLINE KNOT is nowadays very apt to
be termed merely the "BOWLINE," the word knot being dropped."

An alternative definition of this one knot, based upon its active components is - A loop knot made with two active components - A bight component (sometimes referred to as a collar) - and a nipping loop which ranges with loading from a simple hitch component to a half hitch component.  As the normal loop mode is for legs to be loaded roughly 50/50, I believe my original definition of simple hitch component should be amended to Half Hitch Component (HhC).

-----------------------

The other end of the spectrum of definitions is - The Bowline is a Loop Knot...

And yes, we have all seen a host of loop knots - rightly or wrongly - called a Bowline or an XYZ Bowline.  I have even seen the Overhand TIB loop called a 'Bowline' (meaning - loop knot, or simply - LOOP).

----------------------

Then, in between these extremes, there are knots which hold a strong similarity to #1010 in terms of components, functionality, etc. and others which simply seem to have a 'lookalikeness', tying method, or historical naming reference etc.

How can we pull any sense or consensus out of a muddle that has been hundreds of years in the making?  Because the situation is such a mess, only taking an extreme stance is likely to make any sense.  We could make the rather inane modern response of "Whatever" and leave it all as it is and let it continue to fester.  Or we could make the drastic stand that ONLY #1010 is a Bowline and some 're-tucked' variations are 'Security extensions', but not really genuine Bowlines.  The problem of moving to any other cut off point is - where to draw the line - and that really is so subjective as to warrant the apt situation of 'how long is a piece of string?'

NB.  I have looked at the Eskimo, and indeed, (by my offered definition) it is NOT a Bowline because it contains a Bight Component and a Carrick Component, instead of the necessary Bight Component and Half Hitch Component.

@ Dan, I addressed your Myrtle question back at the end of post #70.  By my proposed definition, it is NOT a Bowline because it contains a Simple Hitch Component and a Turn Component - i.e. it is also lacking the Bight Component.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 31, 2011, 07:01:06 PM
I have tried to figure out something that can serve as a simply and unambiguously defined distinctive feature that will separate the nipping loop of the bowline, from the nipping loop of the Karash loop...other than the Dan Lehman s somewhat vague "direct / indirect eye feed" feature . No luck. The closest thing I could think of is a distinction based upon the inclination of the plane of the nipping loop, in relation to its ends. The most effective nipping loop is the flat one, where the two ends and the bight are on the same plane. Then, the nipping power of the nipping loop, on any line(s) that passes through it, is maximum. As the nipping loop gets more "twisted", and its plane more inclined, it is nipping the line(s) that pass through it less effectively - because some tension is "wasted" on friction around the crossing point of the two ends. When it makes a 180 degrees twist, we have a pure crossing knot. Somewhere in between, the pure nipping loop is turned into a nipping loop/crossing knot hybrid, and, at the very end, into a pure crossing knot. Where ? I have no idea...We have to measure the nipping power on the mainline(s) that pass through it, and see if there is a point of maximum rate of nipping power deterioration...From then on, we should speak of a crossing knot, not a nipping loop, and exclude from the bowline group the end-of-line loops that are based upon such crossing knots.
Not a very simple nipping loop / crossing knot distinction, I am afraid... :)
Ashley uses the term "crossing knot" in a number of ways. He will not hesitate to call "crossing knot" the Clove hitch and the Constrictor, as well as many other hitches around poles. He shows the "common" Crossing knot at #206, #365,  #1071-1074, #2077, #2090. The  knot shown there is a little different from the "twisted nipping loop" of the Karash single loop, (shown in the attached pictures), but there is no doubt that there is some similarity, indeed, that enables us to characterize this loop as a crossing knot, or part of a crossing knot. It is not difficult to see a hitch there, at the end/leg of the nipping loop that makes a right turn around the other, i.e. to see the crossing knot as a "nipping loop + hitch" compound knot.
Incidentally, I have discovered a point where the great Ashley makes the same mistake as Derek Smith :) : At ABoK#1420, he describes the Double Harness bend as a compound of two crossing knots, when it is clearly the compound of two hitches - the tails of those hitches are not loaded, as they should, were they crossing knots.(See the third attached picture)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 31, 2011, 07:37:44 PM
Derek, you keep publishing the same picture, over and over again, as a picture of a bowline, when it could well be a picture of a Sheet bend! If a bowline is loaded, ( 50/50, or else), it can not resemble this picture. The sheet bend can, be it loaded or not. This picture might be a picture where the one end goes to the St Peter s church in the Vatican, the Great Wall, the Great Barrier reef, you name it, and then returns and pop up itself again, as the second leg of the eye of a bowline ! So, based on this misleading picture, you believe that there is some relation between the bowline and the Sheet bend, while the picture itself proves that there is none ! The bowline is a knot where three (3) ends are loaded, while the Sheet bend is a knot where only two (2) ends are loaded! Big, Huge difference. You are talking about of "Forces" and all that, and you are ready to compare two completely different structures, because, WHEN THE ONE IS NOT LOADED, it superficially resembles the other, that might be loaded or not !  :)
Derek, you are confused here... :), but I do appreciate your efforts ! The last elimination of the Eskimo bowline from the group of bowlines would make Dan Lehman happy...but it will not change its name, I am afraid, neither its other features, which are similar to the common bowline.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: [Inkanyezi] gone on July 31, 2011, 08:35:34 PM

(snip/
"What defines a Bowline?"

At one extreme we have a single knot - #1010 (in the left hand and right hand variants)

(http://www.motorboatsmonthly.co.uk/imageBank/b/bowline-cover.jpg)www.motorboatsmonthly.co.uk
/snip/

The problem with the image is that it does not depict a Bowline in use, but is a schematic view that shows how to correctly tie one.

The bowline ideally should be loaded equally on both legs of the eye almost in line with the standing part. The nipping turn then takes the form of a turNip, which is different from the nipping structure in the sheet bend. The forces that oppose the spiral of the nipping turn to open come mainly from one of the loop legs, the one that returns through the nip, and the collar U-turn that holds against the standing part, with the end returning through the nip. Below is an image thought to illustrate the Bowline works. A substantial difference is that the continuation into the eye leg from the standing part after taking the turn is not nipped by the standing part, but it is the load on the eye that holds the nip in the turn.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on July 31, 2011, 08:36:54 PM
@ Derek Smith : See the three attached pictures. The first is of a loaded bowline, tied around a large diameter object. The second and the third are of a (loaded or not, does not matter) Sheet bend.
If you insist to see similarities in knots, regardless of how many, and which, ends are loaded or not, as you do in the case of the common bowline and the Sheet bend, why THOSE two knots are different ? Why you say that the same hitch structure, that is present in the Sheet bend, is not present in the Eskimo bowline ? The pictures tell a different story...
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 31, 2011, 11:12:11 PM
@ Derek Smith : See the three attached pictures. The first is of a loaded bowline, tied around a large diameter object. The second and the third are of a (loaded or not, does not matter) Sheet bend.
If you insist to see similarities in knots, regardless of how many, and which, ends are loaded or not, as you do in the case of the common bowline and the Sheet bend, why THOSE two knots are different ? Why you say that the same hitch structure, that is present in the Sheet bend, is not present in the Eskimo bowline ? The pictures tell a different story...

No, the first is a beautifully laid out image of a circular - UNLOADED - Eskimo bowline that you have previously presented to us.

No, the second is a core - it is not a working knot as it has no input and output loading assigned to any of its four legs.

Yes, the third image is indeed as you state a sheetbend (probably unloaded or only lightly loaded)

--------------------

@ Inkanyezi

What is this?
(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=5516;image)

I guess that before we can get down to defining a Bowline we have to reach some agreement on how a Bowline should be dressed and set.  I have climbed on the bowline for a number of years and I would NEVER have dreamt of climbing on a knot so shoddily dressed.  I have however seen knots at the waterfront where the collar has been hugely distended and the half hitch has rotated to nothing more than a turn.  I had always assumed that these (to me failed) examples were either the toll of time or just shoddy knotcraft.

Now I have to ask in all seriousness - Is this how you nautical types genuinely dress and set the Bowline?

Sorry to everyone for going backwards here, but we need to be sure that we are in fact talking about the same constructions, and certainly, this 'Bowline' that Inkanyezi is promoting is like no Bowline I would ever have made.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 31, 2011, 11:36:03 PM
snip...
Incidentally, I have discovered a point where the great Ashley makes the same mistake as Derek Smith :) : At ABoK#1420, he describes the Double Harness bend as a compound of two crossing knots, when it is clearly the compound of two hitches - the tails of those hitches are not loaded, as they should, were they crossing knots.(See the third attached picture)

Hi Xarax,

While we are waiting for a resolution of 'How to dress a Bowline', could I just pick up on the comment you made about #1420

(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=5514;image)

Technically, although I have used common names for some of the components ( such as Half Hitch Component, Simple Hitch Component...) - none of the components are knots, so they are neither hitches, bends, nor anything comprehensible in the world of complete (i.e. functional) knots.

So I would agree with the Ashley description, except that I would say that the crossing knot is in fact the Carrick Component, and so #1420 is a bend created by combining two Carrick Components

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 01, 2011, 12:44:10 AM
the first is a beautifully laid out image of a circular - UNLOADED - Eskimo bowline that you have previously presented to us.

Take a beautifully laid out picture of a LOADED bowline, tied around a large diameter object. It would resemble to this picture 99.99%.

the second is a core - it is not a working knot as it has no input and output loading assigned to any of its four legs.
the third image is indeed as you state a sheet bend (probably unloaded or only lightly loaded)

Take a a beautifully laid out picture of a, loaded or unloaded, Sheet bend. It would resemble to those two pictures 99.99%.

Now, compare those two sets of pictures, like you had compared the UNLOADED common bowline picture, with the (loaded or unloaded ) Sheet bend picture.
Do you see any difference ? If you do, how do you manage to do this NOW, and you have not been able to do the same PREVIOUSLY, when you had presented the misleading, unloaded common bowline picture, and the Sheet bend picture, to show/prove that the knots those superficially similar pictures represent, are related ? Why were the common Bowline and the Sheet bend related, and the Eskimo bowline and the Sheet bend are not ?

you are ready to compare two completely different structures, because, WHEN THE ONE IS NOT LOADED, it superficially resembles the other, that might be loaded or not !  :)

...but you do this to "prove" only the theory about the supposed common bowline-Sheet bend relation, and you forget to do the same with the Eskimo bowline-Sheet bend relation ! So, you try to eliminate the Eskimo bowline from the bowline family, when this bowline has exactly the same superficial resemblance with the Sheet bend, that the common bowline has with the same bend ....The same resemblance with the same knot, the Sheet bend, can lead you to altogether different classifications of those two knots, the common bowline and the Eskimo bowline ! A Janus miracle !
You should not compare the superficially pictorial characteristics of the three-loaded-ends common bowline, with those of the two-loaded-ends Sheet bend, as arguments in favour of a supposed relation between the common bowline and the Sheet bend. However, if you do this, as you have already done, you should be consistent, and do the same in the case of the Eskimo bowline and the Sheet bend. I have shown to you pictures that can help you to do this. And if you do this, you will see that there is no more difference between the Eskimo bowline and the Sheet bend, than between the common bowline and the Sheet bend. If you call bowline the former, you should do the same with the later...unless you owe Dan Lehman a Huge amound of worthless US dollars !  :)

Could you now please restate your answer ?  :) Because, if you continue to insist that the common bowline is related to the Sheet bend, while the Eskimo bowline is not, and the Eskimo bowline should be renamed to Eskimo loop, you are wrong in the first answer, inconsistent in the second, and naive in the third !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 01, 2011, 01:11:55 AM
I would agree with the Ashley description

As Ashley is mistaken on this - because those two structures that form the Double Harness bend are not crossing knots, but hitches, and you are also mistaken to consider that the bowline incorporates a hitch component, it is only natural that you agree with him !  :)

#1420 is a bend created by combining two Carrick Components

However, I , too, agree with you on this !  :) (even if Ido not know exactly what you mean by this cryptic "Carrick Component"...I decipher it as "the hitch component incorporated in the Carrick loop" we were talking about the oyjer day - or in the Carrick bend.) The ABoK#1033, the Carrick bend, the Angler s loop, all those knots do have a hitch component, indeed, they have segments of standing part lines perpendicular to each other, crossing knot components, etc...in fact, all those things that are  completely absent in the bowline !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: [Inkanyezi] gone on August 01, 2011, 06:09:18 AM
@ Inkanyezi

What is this?
(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=5516;image)

I guess that before we can get down to defining a Bowline we have to reach some agreement on how a Bowline should be dressed and set.  I have climbed on the bowline for a number of years and I would NEVER have dreamt of climbing on a knot so shoddily dressed.  I have however seen knots at the waterfront where the collar has been hugely distended and the half hitch has rotated to nothing more than a turn.  I had always assumed that these (to me failed) examples were either the toll of time or just shoddy knotcraft.

Now I have to ask in all seriousness - Is this how you nautical types genuinely dress and set the Bowline?

Sorry to everyone for going backwards here, but we need to be sure that we are in fact talking about the same constructions, and certainly, this 'Bowline' that Inkanyezi is promoting is like no Bowline I would ever have made.

Derek

Of course this is not what the Bowline would ever be dressed like, but I first tensioned it, and then opened it, so that the parts should become more visibly separated. unfortunately we cannot se three-dimensional images on the screen.

What I try to point out is that whichever way you try to dress the bowline, when it is in use, the nipping turn takes a spiral form resembling that of the Gleipnir, and the forces within the central part of the knot are different from the Sheet Bend. When the Sheet Bend is loaded, the free end of the hitch points at an oblique angle somewhat in the direction of its own standing part, while the collar nips it against its standing part. The Bowline on the other hand does not nip the similar part in the same way, but it is almost in line with the standing part. The "knot" in the image is deliberately opened, so that the collar is very loose, but it is to show the works of the knot, its central feature, the nipping loop, that is almost straight, almost in line with the standing part.

The Bowline always takes that form under load, when heavily loaded or with the load repeatedly applied. Even when you dress it very neatly, if the load is heavy, the bight that forms the collar will be drawn out a little and the former HH made in Sheet Bend fashion will form a turNip. Provided the two legs of the eye are not too widely apart, it will not collapse further.

A neatly dressed Bowline will be snugger, but I eased the bight of the collar, so that the turNip should be more clearly seen.

Post Edit: Below I inserted a photo of a Bowline that was first beautifully dressed, just as in the Motorboaths Monthly image, but then was exposed to heavy stress by loading it with repeated jerks. Invariably it takes the "sloppily dressed" form, drawing out the collar and orienting the nipping turn almost parallel with the standing part. Note the direction the end takes. This is typical for the Right-handed Bowline.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 01, 2011, 10:57:33 AM
What is this?
Is this how you nautical types genuinely dress and set the Bowline?

YES ! This is a detail of a picture of a properly dressed and tightened bowline. The loadings of the standing end, the eye leg of the standing part and the eye leg of the bight happen to be equal.  :)
Make an educated guess : Is it a commn bowline, or an Eskimo bowline ?
Derek, give up... :) There is no way to distinguish if this is a detail of common bowline or a Eskimo bowline !  Why then the one is a bowline, and the other a non-bowline loop ?
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 01, 2011, 12:18:47 PM
Whoever is able to untie this Gordian knot, and solve the riddle of the previous post, is kindly requested to exercise his abilities in the following, too. ;
Does the attached picture show a detail of a common Janus bowline, or a detail of an Eskimo Janus bowline ? Does it happen that the "first" collar is tied around the standing end, and the "second" collar is tied around the eye leg of the bight, or the opposite  ? Which is the standing end, and which is the eye leg of the standing part ?
If we can not distinguish, due to the local symmetry of the knot s nub, the former from the later, why the one should be called a bowline, and the other simply a "loop" ? "Janus bowline" and "Janus loop", sounds like a very "Janus" situation to my ears... :)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 01, 2011, 01:00:19 PM
(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=5526;image) 120 degree Eskimo

(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=5530;image) 120 degree Janus Eskimo

But these are only games - now dress, set and load your knots and lets see if they behave the way Inkanyezi has demonstrated.

If we can show that the 'correctly' dressed, set and loaded bowline regularly takes up the Turn Component instead of the Half Hitch Component, then my proposed definition will need to be amended a third time.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 01, 2011, 02:02:40 PM
But these are only games - now dress, set and load your knots

They are not games ! They are made by three tensioned/loaded legs, two of whom can be well connected and form a loop, as in a "dressed, set and loaded" common bowline or Eskimo bowline,. without any change in the detailed pictures !
You proposed this theory, you have the burden to test it...Tie your own knots, because you will not believe me, anything I show to you ! If you wish to test your "ability to force square pegs into round holes", go on, use more carefully chosen words, like this "games..."(sic), to try to make my arguments look ridiculous...

Why does knotting makes this thing to honest, decent people, I wonder...I , for myself, I will not continue along this slippery road. I already wrote thousands of words because I respect you, and I ,really wanted you to look on the matter more closely. Either you have not read them, or you read them but believe they are not worth reading... which is about the same thing. Eitherwise, it seems you have not understood, or wished to understand, anything at all.
Good luck, Derek, and  enjoy knotting  !   :) I have already forgotten the whole issue.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 01, 2011, 06:55:36 PM
I guess that before we can get down to defining a Bowline we have to reach some agreement on how a Bowline should be dressed and set.  I have climbed on the bowline for a number of years and I would NEVER have dreamt of climbing on a knot so shoddily dressed.  I have however seen knots at the waterfront where the collar has been hugely distended and the half hitch has rotated to nothing more than a turn.  I had always assumed that these (to me failed) examples were either the toll of time or just shoddy knotcraft.

You can see rather loose collars in photos of bowlines
in sailing/yachting magazines, and at the waterfront, as you
note; I have posted images here of bowlines that have capsized
into a sort of pile-hitch noose structure (with yet much curve
in the SPart) --something I've seen to such frequency to make
me wonder if the result is intended!?

Different materials give different results (along with varied forces);
rockclimbers' kernmantle ropes won't hold such a loose shape
(and might not hold any unextended bowline) very long,
if at all --the stiff rope wants to "unwind."

Of course this is not what the Bowline would ever be dressed like, ...  [rdl : Oh, I won't go this far!]

What I try to point out is that whichever way you try to dress the bowline,
when it is in use, the nipping turn takes a spiral form resembling that of the Gleipnir,
...

Hmmm, I don't see the turNip in the Gleipnir getting so far as
a spiral --which is dangerously close to losing grip.  Rather, it only
goes towards a turn from the set *hitch* geometry.

Quote
The Bowline always takes that form under load,
...
Below I inserted a photo of a Bowline that ... was exposed to heavy stress ...

Yes, and I see more *hitch*/=>*turn* than *spiral* in this, still.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 01, 2011, 07:18:43 PM
YES ! This is a detail of a picture of a properly dressed and tightened bowline.

The loadings of the standing end, the eye leg of the standing part, and the eye leg of the bight happen to be equal.  :)
Make an educated guess : Is it a commn bowline, or an Eskimo bowline ?
Derek, give up... :) There is no way to distinguish if this is a detail of common bowline or a Eskimo bowline !
Why then the one is a bowline, and the other a non-bowline loop ?

There are three *ends*, Xarax : why do you offer only two choices?!

And the point is --re "games"-- that you here have shifted the issue
from What distinguishes <any_eyeknot> from <other_eyeknots>?
--i.p., what characterizes *a* "bowline"?--
to the more general, basic, and profound question
What defines an eyeknot? !!

For the structure you present, with the equal angles of incidence
among *ends* (need a better term for "limbs" of knots in general),
(In practice, though, were an eye extant and figuring in the loading,
angles and associated tensions of the three *ends*.))

Incidentally, I fancy one of the "Janus" structures partly with
the somewhat whimsical thought that, if one just ensures that
collars go around both an eyeleg & the SPart --no matter the
order--, one is okay with the result either way (for those who
might find making the discrimination a major challenge
--the UNinterested knotting folks) !

And re the profound issue manifest in this example, it begs
the question of using "eye" by me in "eyeknot" --for there
might in fact be no such structure.  (My example builds from
using a bowline to fore corner cleats of a small barge,
of cleating the line (to improve its steerage), and then some
accident severs the bight between cleats along the barge
--the *knot* all this time is closely surveyed and never
changes in discernible quality, yet clearly with the severed
rope there is no (longer an) eye.)

In the case of building definitions, we should look to some
established *canonical* form and not to exotic cases;
I submit that the canonical form of an(y) *eyeknot* is a knot of
a single Piece_of_Flexible_Material with 4 *ends* of which One stands
in tensional opposition to another Two, and the 4th is untensioned
(and, yes, it matters that the tensioned one flows into one of
the tensioned 2, not to the untensioned 4th (which would be
e.g. a *bight hitch* if so).)

--dl*
====

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 01, 2011, 08:12:55 PM
There are three *ends*, Xarax : why do you offer only two choices?!

Because I didn't want to offer to Derek Smith and you the easy satisfaction to be able to eliminate the third possibility... :) (The third choice can be eliminated by the first sight, you know...)

need a better term for "limbs" of knots in general

I agree on this. Suggest something."Limb" sounds good...

That was exactly my main point. A theoretical counter-example, in a special, yet no "limit" case. This is the case we really have a Janus-like situation, where the two "faces" of the two bowlines structures, that of the common bowline, and that of the Eskimo bowline, are equivalent and indistinguishable.

if one just ensures that collars go around both an eyeleg & the SPart --no matter the
order--, one is okay with the result either way

That was also one of my points, so the common bowline and the Eskimo bowline are indistinguishable, even in their security/holding aspects. However, I think that it is better to U-turn the first collar around the most tensioned "limb", which, in most cases, is the standing end outside the eye. That is because the first collar bears the most of the tension forces, and we do not want this collar to be deformed, due to a deformation of the segment of the rope around which the collar is U-turned, and which the collar pulls towards the nipping loop.. I might be mistaken in this, though...You could examine this in more detail.

In the case of building definitions, we should look to someestablished *canonical* form and not to exotic cases

Yes, I agree, and I have said the same when DerekSmith offered his example of the 0%/100% loaded bowline, which is indistinguishable, indeed, from the Sheet bend. ( and it is the ONLY case where this happens,,,) However, my 120 degrees counter-example is not an exotic case, in the sense that it is not a case on the "limit" ; it is a case on the "middle", albeit a very special one.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 01, 2011, 11:40:46 PM
@ Derek Smith, with playful intentions... :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DDK on August 02, 2011, 12:58:44 AM
. . . There is no way to distinguish if this is a detail of common bowline or a Eskimo bowline ! . . .

Unless I'm missing something, you must mean a common cowboy bowline as I do not think this can be a common bowline.  Terrific use of symmetry to help capture some thought-provoking points.

DDK

(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=5526)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 02, 2011, 01:38:26 AM
you must mean a common cowboy bowline as I do not think this can be a common bowline.

Derek Smith got it, too...I should have left longer tails ... :) I use the term "common bowline", to denote both, the left and the right handed bowlines, in contrast to the term "Eskimo bowline" ( an Eskimo bowline can also be tied in a left and a right handed form). I would prefer a pair of antonyms, for those two similar types of end-of-line loops, perhaps (+) bowline and (-) bowline, cis- and trans- bowline  :), or something like that...The pair "bowline-antibowline" might also be acceptable, if it is interpreted like the "particle-antiparticle", or "cyclone-anticyclone" pair, and not as acceptance - denial of some essential bowline property, present in the bowline and absent in the anti-bowline.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 03, 2011, 06:06:51 AM
The pair "bowline-antibowline" might also be acceptable, if it is interpreted like the "particle-antiparticle",
or "cyclone-anticyclone" pair, ...

It is precisely this 2nd that is my motivator; and the point of
determination is the side of the nipping loop from which the
tail is returned (enters) --on the SPart's side (i.e., where SPart
crosses itself) or opposite.

(And beyond this I have "false bowline" though "pseudo-bowline"
might be better (unless I determine separate tasks, each in need).)

;)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 03, 2011, 08:31:04 AM
the point of determination is the side of the nipping loop from which the tail is returned (enters) --on the SPart's side (i.e., where SPart crosses itself) or opposite.

I, too, agree on this..

I have "false bowline" though "pseudo-bowline" might be better

...but not on this, of course !  :) I wish to retain the generality in the definition of a bowline, independently of the particular side of the nipping loop the tails enters it for the first time, or exits from it right afterwards. A general definition would be a definition for the (+) bowline, as well as for the (-) bowline, the Eskimo thing. If there is a miracle in the bowline mechanism, it takes place in the common bowline AND in the Eskimo bowline, and this has to do with how perfectly the spectacular anti-slippage action of the nipping loop is combined with the mechanical-capstan advantage of the collar, to generate this miraculous end-of-the-line fixed loop.
The reason I do not use the term "antibowline" is just this : one can very easily, almost unnoticeably, jumb from an antonymic definition, denoting simple opposition, to a definition denoting negation ( of the "bowline property" ). The counter-example of the 120 degrees bowline, where we are not able to distinguish, by a local inspection, if we have a common bowline or an Eskimo bowline, is not an"extreme" case, a case "on the limit": On the contrary, it is a middle-ground case, a case "on the middle",  that should have convinced you, by now...Allow me to repeat/sing a previous post :
I believe that, from time immemorial, people tied bowlines in both ways, just preferred the common bowline, when the eye legs were close to be parallel ( in loops tied around small diameter objects, where the knot s nub is far from the object ), and preferred  the Eskimo bowline, when the eye legs were close to be aligned ( in loops tied around large diameter objects, where the knot s nub is close to the object). There is no essential difference : the collar, an extension of the eye leg of the bight, helps the nipping loop secure the tail, and makes a U turn around the line that is more aligned with the eye leg of the bight. If the loop is elongated, because it is tied around a small diameter object, the collar makes a U turn around the segment of the standing part outside the bight. If, on the other hand, the loop is round, because it encircles a large diameter object, the eye leg of the bight is more aligned with the segment of the standing part inside the bight, so it is natural to the collar to make a U turn around this segment of the standing part, i.e. around the eye leg of the standing part.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: [Inkanyezi] gone on August 03, 2011, 10:41:11 AM
I think I am beginning to get xarax's vision here. The most extreme case of the Bowline is the most common one, where the two legs of the eye are almost parallel and pointing away from the standing part, and it is in this form the turNip is evident. When legs are wider apart, the nipping turn takes another form, which is the same as in the Eskimo Bowline.

Now I have tried to collapse bowlines that are tied around very wide objects, and they will not collapse, neither will the turn take the turNip form, but it resembles the Sheet Bend form somewhat, although differently loaded.

In order to make the knot collapse completely, I tried easing the collar a lot, but still it failed to collapse, even in shock cord. It winds the collar around the knot and still holds. But when the collar is snugly worked from start, it only goes so far as to allow the standing part to exit the knot almost straight from the nipping turn. (Which of course is a round turn, rather than a spiral, we already had a name for that.)

I don't know whether the discussion can be taken much further, and I still think of it as more a theoretical than a practical issue. I learned a bit more about one of our most used knots, and it did not change the world.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 03, 2011, 11:38:05 AM
In light of the comments by Xarax and Inkanezi, I have just completed a number of trials, static loading and dynamic loading, well dressed and set Bowlines (#1010) in a number of different cords ranging from 0.8mm Spectra right up to 18mm cored braid.

The objective was to determine if the #1010 Half hitch Component underwent transformation into the Turn Component as suggested when the Bowline is loaded.

The result is that indeed IT DOES...

The more 'elastic' the cord, the lower was the tension needed to rotate the Half Hitch Component (HhC) into a Turn Component (TC), and in the most elastic Polyester braid, the Turn Component even disengaged contact of the coil and started to morph into an Open Spiral Component, while at the other end of the spectrum, very low stretch materials were virtually at breaking point before any noticeable morphing could be detected (and then only slight).

Of Note; once the bight collar has been elongated (pulled through the nip) by the tension induced rotation, it remained extended in a form approaching the 'sloppily dressed' state I commented on earlier.

Consequently, it is necessary for me to amend my proposed definition a third time, to incorporate the morphing from Half Hitch Component to Turn Component when the knot is subjected to high loads in relatively extensible cords.
Quote
A Bowline is defined by Ashley in #1010.
----------------------
It is a loop knot comprising two interlocked components -  a Bight Loop Component and a Half Hitch Component
Under conditions of high load in extensible cordage, the Half Hitch Component will morph open to form the Turn Component and may even show signs of further morphing into the Spiral Component.

[NOTES - with the exception of the 12mm dynamic Kern-mantle safety rope and the 18mm cored braid (their tensile strength exceeded the capacity of my test facility), the test cords were extended until they failed with the Bowline - this was assumed to be ca 50% of line strength.  In tests, the cords were then subjected to ca 30%  loading by taking the knot to 60% of the extension exhibited at failure.]

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 03, 2011, 05:49:02 PM
the point of determination is the side of the nipping loop from which the tail is returned (enters) --on the SPart's side (i.e., where SPart crosses itself) or opposite.

I, too, agree on this..

But a problem I run into is that many such antibowlines have a strong
tendency to exhibit less a **loop** than a **spiral** --YMMV per knot,
but in some, it's quite hard to have the part that should be a **loop**
staying something approaching a plane, crossing points proximate,
even if not touching.  AND, moreover, it might be argued that such
a **spiral** base is DESIRED/expected.

And I really want a classification that doesn't hinge on loading variance
(why I favor calling a "noose" things that show the structure's SPart
really playing no **knotting** role but just being hitched to (e.g.,
the venerable two half-hitches & midshipman's hitch
--these, to me, are not, in their entirety, **knots**, but **compound
structures** which contain a knot (the hitch to their SParts)).

Quote
I have "false bowline" though "pseudo-bowline" might be better

...but not on this, of course !  :)

You might if you understand my meaning.  "Read more than 1 in 30 words..." !
I indicated that these were other terms and for other uses.
I.p., for knots in which there appears to be (or is) a nipping loop
but in which the continuation does not go into an eye leg (immediately),
but e.g. forms a collar around the eye legs, and THEN feeds into one
of them.  So, one has the apparent structure of a loop but not quite
--"false"/"pseudo".  One might expect nipping & strength characteristics
to be similar, and knots of this sort can have your "proper collar" and
be easily untied; in the slippery HMPE cordage they will likely NOT
slip (collapse the eye as shown for the dbl.bwl  by Brion Toss's video).

Quote
I wish to retain the generality in the definition of a bowline,
independently of the particular side of the nipping loop the tails enters it for the first time,
or exits from it right afterwards.

I too want generality (if it indeed can work --see my doubts re **spiral**),
and more so than you I thought, re "proper collar",
except in the enboldened utterance above where I think you must
imply accepting the *improper* simple wrap I would take,
such as in the Myrtle --which serves a collaring role,
but has the tail exiting through the loop opposite to #1010.

Quote
A general definition would be a definition for the (+) bowline,
as well as for the (-) bowline, the Eskimo thing

I think I'm coming to see the latter as a boundary-crossing knot
--in the canonical form of SPart-vs-eye_legs (not equilateralism),
setting the collar tight will produce a core nipping structure as
much a crossing knot as a turNip. and I'm thinking that
it's best not to try to push this one way or another, just as with
that carrick loop which can also have either core nipper.

NB: We have followed the OP's topic of trying to articulate the essence
of "a bowilne "; but this might be a biased start --to pic from one
reasonable set of knots this one and then ... :  we might have
started with a broad set of knots (albeit those thought to be like
the bowline and then sought to characterize & group them,
maybe rejecting some as belonging.  And in such an exercise,
I submit that one might see JUST the turNip as the essence,
and then look to group according to what knots preserve that.

I believe that, from time immemorial, people tied bowlines in both ways,

I clipped a clothing(?) ad that featured a yacht in which the two lines
tied to the sail were . . . tied in both ways !  And I surmised ignorance
more than some equanimity or love of variety (or even pressure of some
circumstance) --conjecture.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 03, 2011, 07:54:48 PM
many such antibowlines have a strong tendency to exhibit less a **loop** than a **spiral**
it's quite hard to have the part that should be a **loop*staying something approaching a plane, crossing points proximate,
even if not touching.

We might expect that a helical (helix, not spiral) nipping structure, where the two points - when/where there should be only one - are not very far from each other, is more effective, as a nipping structure, that when we have a "proper" plane nipping loop, and one crossing point, but a "twisted" nipping loop, with limbs in a pronounced angled/elbow configuration. In the helical case, we have a slightly less nipping power from the maximum, but in the "twisted" case, we have much of the nipping power wasted by friction, and much of the tensile forces dissipated by the oblique loading of the two limbs.
So, we do not know where we have a more effective nipping structure, and where we have a less effective one, i.e. we can not correlate the helical structure with a supposedly less of a bowline "anti- bowline" property, and the plane structure with a "genuine bowline...Why we should prefer a slightly twisted plane nipping loop, as in a (+) bowline, than a slightly open helical nipping structure, as in the (-) "anti-bowline" ? No, the fact that the nipping structure is open or closed, is not a measure of the effectiveness of the basic bowline structure, so it can not be an element of "discrimination" between the two forms of bowlines.

And I really want a classification that doesn't hinge on loading variance...

Me too. More than that, I want a classification that does not takes into account even the global differences of the two forms - because we have such a strong local symmetry, that is always existent, but it is revealed most clearly in the 120 degrees "equilateral" ( strictly speaking, equiangular) case, the Janus (+) bowline / Janus (-) bowline, common bowline / Eskimo bowline structure.

I indicated that these were other terms and for other uses, I.p., for knots in which there appears to be (or is) a nipping loop, but in which the continuation does not go into an eye leg (immediately),  but e.g. forms a collar around the eye legs, and THEN feeds into one of them.  So, one has the apparent structure of a loop but not quite --"false"/"pseudo".  One might expect nipping & strength characteristics to be similar, and knots of this sort can have your "proper collar" and
be easily untied;

They do not have a "proper "nipping loop !  :) Lets agree that the nipping loop should feed the standing end and the eye leg of the standing part immediately/directly, and not through St Peter s Cathedral, the Great Wall or the Great Barrier reef... :) Why reserve any compound "bowline" name for such a compound "not-bowline" knot ? We should not use the term "bowline", for any of those knots !

the *improper* simple wrap...such as in the Myrtle --which serves a collaring role, but has the tail exiting through the loop opposite to #1010.

We have enough problems with the "proper" or not "collars", we should not try - at least for the time being - to solve even more, by accepting "proper" and not "collaring roles"  :) ! A not-proper collar-role-playing, collar-like structure, can be even more effective than a proper collar, indeed, but if I accept it as a collar, I open the Pandora s box, in the sense described by knot4u...
(And the tail is not "exiting through the loop opposite to #1010 "  I refuse to describe every simple fact of ropes and knots structures by an Ashley number !! The tail is not exiting through the loop from the opposite direction it followed when it was entering into it for the first time, as it should, if the collar was a "proper" bowline one.)

I think I'm coming to see the [Eskimo thing] as a boundary-crossing knot...setting the collar tight will produce a core nipping structure as much a crossing knot as a turNip.,  and I'm thinking that it's best not to try to push this one way or another

So, either you throw out with the beautiful baby Eskimo, with the dirty water of the crossing knot-based structures, like the ugly Karash thing, or you accept them both as bowlines. Back to the square one !  :)

...I submit that one might see JUST the turNip as the essence,and then look to group according to what knots preserve that.

If so, you should be prepared to deal with many more "bowlines" than the average knot tyer, bowline user, or man in the street / harbour would like to, believe me...What the purpose of a definition that only a few people will accept, fewer still will use, and only a handful will understand ?  :)
(Heraclitus of Ephesus : People must "follow the common (hepesthai tō ksunō)" and not live having "their own judgement (phonēsis)". )
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 04, 2011, 05:06:18 AM
I indicated that these were other terms and for other uses,
i.p., for knots in which there appears to be (or is) a nipping loop, but in which the
continuation does not go into an eye leg (immediately),
...

They do not have a "proper "nipping loop ! ...
Why reserve any compound "bowline" name for such a compound "not-bowline" knot ?

Because they appear to be such (as is the case for some
such names in biology, e.g.) --and will take scrutiny to
conclude "Aha, it is NOT (truly) ... !".  (And some folks like
Derek will have some satisfaction in seeing the semblance
acknowledged this much, at least.)

(But these are still just sketches of thought at the inchoate
formation of a possible nomenclature, yet to be brought into
even some "beta" stage of application.)

Quote
the *improper* simple wrap...such as in the Myrtle --which serves a collaring role,
but has the tail exiting through the loop opposite to #1010.

We have enough problems with the "proper" or not "collars",
we should not try - at least for the time being - to solve even more,
by accepting "proper" and not "collaring roles"  :) !
...

Well, of course, I actually don't care about the collar, as I'm looking
at the eye knots that are based on the turNip core, which use
and stabilize that --the Gleipnir has no collar at all, but to make
an eye knot one needs to somehow effect the stabilization of the
turNip without the benefit of opposed tails brought through it;
I'm happy with whatever works.  ("The" bowline just happens to
come along as one solution, among the many --many unknown.)

Quote
I think I'm coming to see the [Eskimo thing] as a boundary-crossing knot...setting the collar tight will produce a core nipping structure as much a crossing knot as a turNip.,  and I'm thinking that it's best not to try to push this one way or another

So, either you throw out with the beautiful baby Eskimo, with the dirty water of the crossing knot-based structures, like the ugly Karash thing, or you accept them both as bowlines. Back to the square one !  :)

No, I shrug at the *knots* that can take forms that confound my
classification, that span my artificial boundaries --the duckbilled
platypuses of knots, if you will.

Quote
...I submit that one might see JUST the turNip as the essence,and then look to group according to what knots preserve that.

If so, you should be prepared to deal with many more "bowlines" than the average knot tyer, bowline user, or man in the street / harbour would like to, believe me...What the purpose of a definition that only a few people will accept, fewer still will use, and only a handful will understand ?  :)

That cannot be avoided --the "deal(ing) with..."--, for the knots are
there (to be discovered, to be ignored), no matter the naming.  And
a slew of (non-"bowline") names isn't going to make it any simpler.
(And when you realize what quite simple things the occasional rope
user & knotter can confuse, you hardly want to limit your own doings
to whatever lower common denominator might exist (you might doubt
there is even any!) !!)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 04, 2011, 08:16:21 AM
I have just did what it seems that you suggest : I forgot the bowline solution, I tied a planar nipping loop, and I have thought of ways to stabilize that structure by using the available free end, the "tail", for that purpose, and that purpose only :  to prevent the planar nipping loop turn into a helical nipping loop, and finally into a straight line, when loaded. In 15 minutes I came up with 15 solutions... that achieved that purpose and that purpose only, and only as a collateral by-product, those solutions managed to secured the tail itself as well...( And this happened even if they were no meant/designed to do this, it happened just because of the necessarily convoluted structures formed by the tail, that were subsequently tightened by themselves, "locked" on the nipping loop s limbs, and turned into safe hitches...)
What I mean is this : If you forget that the main purpose in the bowline is to secure the tail - not to stabilize the coil of the nipping loop - and that this purpose is achieved by constricting the tail twice ( at least ) into a nipping loop, and after, and after only, this main task has been achieved, and as a collateral by-product, and as a collateral by-product only, this nipping loop happens to be stabilized as well, by the mere presence of the formed structure by the tail, the one (at least) "proper" collar, if you forget this, you open the Pandora s box, or a can of anti-knot4u worms !
The main purpose of the stone-age man that discovered the bowline, was to secure the tail on the standing part, to form a stable end-of-line loop, to tie his wife with... He figured out to form a nipping loop on that part, so he could pass the tail through this nipping loop, and consrict and secure the tail there, by the nipping action of the two loaded limbs of this loop. Once going through the nipping loop was proven- by trial and error- to be not enough, so he tried to do the same thing twice... He could, at this time, have tied a common nipping loop, or a Eskimo nipping loop, or a Myrtle, we do not know...But then, the "proper" collar solution survived the evolution pressures by what ( incidentally, as a collateral by-product ) this structure  achieved, in an almost perfect way, by just "being there" : the stabilization of the nipping loop. The "proper" collar solved the problem of the tail, that was, and still is, the main problem of any end-of-line loop, and then, miraculously, a historical accident took place : the stone-age man, (and at least one of his descendants... :)), realized that this most simple structure was preventing the nipping loop to be turned into a helix, and, eventually, into a straight line...This first ingenious brave man died, some of his descendants happen to survive, and many of them still live : but they forgot the purpose of their ancestor, and turned the whole thing upside down! They think that the stabilization of the nipping loop is the main task of the bowline, and, as this task is achieved, by whatever sufficiently convoluted structure, the tail will be secured as well - will happen to be secured. Even if this is not meant to happen, if the initial motive is long forgotten, it will happen :  the tail will be secured, as a collateral by-product of the convoluted structure it forms.
Wrong, this view of our ancestor s tool...Not wrong because it leads to wrong new knots ( it might well lead to better, if only more complex end-of-line loops ), but because it leads to wrong definitions of the old ones, the knots in the bowline family. I tell you, forget the main purpose of the bowline, confuse the main purpose of the nipping loop - that has to do with the tail, and not with itself ! - forget the presence of the "proper" collar that is but the simplest structure that achieves to pass the tail through the nipping loop twice, and, at the same time, happen to stabilize this nipping loop as well by its mere presence, and then you enter into a vast realm of possible end-of-line loops...We can say that they are inspired by the bowline, but it is far fetched to say that they are bowlines. I would be glad to get rid of this pesky Karash thing and all the possible crossing-knot based loops, but keep the baby Eskimo alive within the tube, and here comes this descendant, who wishes to open the knot4u can of worms...and force the few remaining readers start running towards the tree swing...
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DDK on August 05, 2011, 05:30:41 AM
. . .  We have followed the OP's topic of trying to articulate the essence
of "a bowilne "; but this might be a biased start --to pic from one
reasonable set of knots this one and then ... :  we might have
started with a broad set of knots (albeit those thought to be like
the bowline and then sought to characterize & group them,
maybe rejecting some as belonging.  And in such an exercise,
I submit that one might see JUST the turNip as the essence,
and then look to group according to what knots preserve that.  . . .
--dl*
====

These comments strike a chord as I wonder how different our discussion would be if we were attempting to describe a family of knots which we were looking to label as the TURNIP LOOPS.  In this case, is it not likely that a significant variety of structure and function would be more easily expected and accepted?

If we label a family as BOWLINE LOOPS, do we not because of the notoriety of the bowline have some narrower expectations of structure and function?  I believe the bowline is very widely known as a rescue loop, not exclusively, but prominently.   Do we want to label knots as bowlines which would / could / should never be used as a rescue loop?  I would have no issues with a member of the TURNIP LOOP family not being a rescue loop.  I feel somewhat differently about members of the BOWLINE LOOP family not being able to function at some level as rescue loops (security, ease of tying, etc.).

In my opinion, the use of the name of an archetype in the naming of a family of knots has in some cases more specific or restrictive implications.

DDK

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 05, 2011, 05:59:05 PM
If we label a family as BOWLINE LOOPS, do we not because of the notoriety of
the bowline have some narrower expectations of structure and function?

Of structure, and with the familiarity of that knot.

Quote
I believe the bowline is very widely known as a rescue loop,
not exclusively, but prominently.   Do we want to label knots as bowlines which
would / could / should never be used as a rescue loop? ...

This is ironic, in light of the fact that many SAR organizations have or had
banned the bowline from use in . . . rescue work.  (And the maritime
pool of users probably don't consider this eyeknot primarily on that
exceptional function --one might even be led to the belief by Ashley
that the midshipman's knot  is de rigueur in emergencies.)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 07, 2011, 11:18:22 AM
As an example of a bowline, where the function of the collar as a stabilizing structure of the nipping loop is not needed at all, is shown in the attached pictures. This variation of the Double bowline - that, for the time being, let us callit a  "double, crossed-coils nipping loop" bowline - is based on a very stable and tightly tied over the eye leg of the bight double nipping loop, so the collar is needed only to allow the tail to pass through the nipping loop for a second time (See (1)). The way the eye leg of the standing part exits the knot s nub, confined between the second coil and the standing end, makes any stabilizing role of the collar only a secondary one. (Read reply#132, for what this might mean for the definition of the bowline).
I believe that this bowline is " a relatively simple practical solution, to help keep this forum on the track of talking about practical knots..." :), besides tree swings and corsets tying...

1)  http://igkt.net/sm/index.php?topic=3315.msg19890#msg19890
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 07, 2011, 11:43:44 AM
The "Myrtle" loop version of the previously shown bowline. Even myself can see a hitch there  :), although this hitch function of the "improper", Myrtle collar is helpfull, but not nessesary : the second time the tail have gone through the nipping loop, it could well had passed above itself, and not below, as in the dressing shown in the pictures. Of course, when it passes 'below", the loaded leg of the tail loop ( the eye leg of the bight) squeezes / compresses the other on the surface of the two colis of the nipping loop, so the tail is secured better by this more secure, tighter hitch.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 08, 2011, 05:43:08 AM
As an example of a bowline, where the function of the collar
as a stabilizing structure of the nipping loop is not needed at all,

???  The collar is as much needed here as it is for #1010, which
we might recall at least has a published version devoid of a collar
--videlicet, the bellringer's loop !

Quote
This variation of the Double bowline ...

... was devised by me some decades ago with an eye to making
the SPart take a gradual curvature into the knot.  I had one token
of it tested (tied in rather common 1/4" med-soft laid nylon rope),
and it faired reasonably well, but nothing earth-shattering.  (I pushed
the u-turn father from the collar, to make the SPart's helix more

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 08, 2011, 09:20:35 AM
As an example of a bowline, where the function of the collaras a stabilizing structure of the nipping loop is not needed at all,

???  The collar is as much needed here as it is for #1010

No. I am surprised, (to say the least...) that you say something like this, but, perhaps, you have not tied, loaded and tried this loop times enough, recently enough...or you have tied and/or remember something else ?? When you will tie, load and try it, please, correct this erroneous comment !
This loop can stand by itself, without a collar, and be loaded very hardly. It is miraculous how well it can stand by itself. I have tried it MANY times, with MANY kernmantle climbing  ropes, 6 to 12 mm. ( so, MANY, not only "one token of it...")
ON THE CONTRARY, the un-collared loop of the common ( right or left hand ) bowline, can not !... of course, because the loop is instantly deformed into a helix, and then into a straight line...The simple passage of the line of the eye leg of the bight through the nipping loop, without a collar on it, is not enough to stabilize the nipping loop of the common bowline, while it can stabilize the double, crossed-coils nipping loop very well. The common bowline does need the collar, to stand as an end-of-line loop, the loop I have presented does not. Of course, one could not imagine or predict  that, one has to actually tie it, as I did, and try it, as I did ! ( and then remember what he has seen, as you do not !  :))
I met this loop while I was trying to simplify another, more complex loop based on the double overhand knot, and I met the the double-overhand-knot  based loop when I was trying t simplify some collared versions of it, and those collar versions of it when I was trying to incorporate the Versatackle self-locking mechanism into one single knot...I have not met this bowline by tying double bowlines !
I presented this bowline as a counter-example to the claim that the collar is needed to stabilize the nipping loop. This might happen, indeed, but only incidentally, as a secondary by-product of the presence of the "proper" collar :  because the primary purpose of the bowline is to be an end of the line loop, and for this it should fix the tail on the standing part... and the collar is a structure of this tail, and the the primary purpose of this collar is to double the number of times the tail passes through the nipping loop.
This loop needs the collar only as an additional means of security, not as a stabilizing means. (as does the "ABoK#1010", and every common or Eskimo bowline...) That was the purpose of my post.

This variation of the Double bowline ...... was devised by me some decades ago with an eye to making the SPart take a gradual curvature into the knot.  I had one token of it tested

Congratulations ! That is why you have forgotten it !  :) Decades is a long time for one, after a certain age, to remember a knot... Along with the other dozens of dozens of the knots you devised (?!?) :) ( nothing earth shattering, you just saw something anybody else could do...and then you have forgotten it, like anyboy else could do, too...), it is not a miracle that you have tied this, too...However, you have not understood its importance, not then, not even now, decades later !  :) Take your time, because I am sure that anybody, has he decades of knotting experience or not, will see immediately that this loop is stable without a collar, while the "ABoK#1010", as you keep naming the common right hand bowline, is not ! My 16 years old son, that was not born when you were starting to forget this loop, realized it at once !  :)
Regarding the nonsense of priority, read the following comments by me, at another occasion :
...as you should have known by now, questions about priorities are not my cup of tea... :)
This : ["I"] was the FIRST ONE", sounded like a "mine s-is-bigger-than-yours  :) declaration to my ears...

P.S  It is vary sad we have to prove (?!) simple thing we say, with pictures...See the suspended chair, and then try to do the same - as Dan Lehundini claims it can be done - with "ABoK1010"... :) Who is, or will be, in a state of suspended animation ?
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 09, 2011, 05:54:32 AM
As an example of a bowline, where the function of the collaras a stabilizing structure of the nipping loop is not needed at all,

???  The collar is as much needed here as it is for #1010

No. I am surprised, (to say the least...) that you say something like this,
but, perhaps, you have not tied, loaded and tried this loop times enough, recently enough
...or you have
. . .

circumspection :  I realize that knots need do more than
bear loads at some point --or, at least, the expected use
of a knot requires that its integrity isn't lost the moment
you look away, put it aside, and slacken the line.  This
is something your teen-age son might be excused to be
overlooking ("at once" ; with reflection, he might do better),
but not you, who boast of wet sea boots and maritime
bowline  usage.

Your flair for drama will win you a photo from me, before
I retire.  Shown is some 5/8" CoEx PP/PE laid line tied in
a bellringer's loop (i.e., #1010 *de-collared*) bearing much
more weigth than that empty chair of yours --sit your bum
(or you son's) in that chair and THEN take your photo(!)--;
in fact, it has 125# of barbell weights suspended from it.
Behind and not much visible is like-sized manila rope in
which I stood in a (lousy) 5:1 pulley, locking a 'biner
(so, > 200#), in the same knot.

Now, to be sure, if it came to comfort and assurance, I
would prefer to sit with you and your structure (though
that kernmantle is making me wary) vs. the other.

But, again, my point is that stabilization of the knot is more
the collar is needed for that, in both of these cases.

Quote
ON THE CONTRARY, the un-collared loop of the common ( right or left hand ) bowline, can not !
... of course, because the loop is instantly deformed into a helix, and then into a straight line...

You may examine my photo for edification, and then,
as you say, "please, correct this erroneous comment ! ".

Quote
Regarding the nonsense of priority, read the following comments by me, at another occasion :

...as you should have known by now, questions about priorities are not my cup of tea... :)
This : ["I"] was the FIRST ONE", sounded like a "mine s-is-bigger-than-yours  :) declaration to my ears...

I made no statement of "priority", and --what I think you
are whining about-- simply stated my familiarity with the
knot (which included my first testing, by a then IGKT member).

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 09, 2011, 12:45:17 PM
I realize that knots need do more than bear loads at some point --or, at least, the expected use. This is something your teen-age son might be excused to be overlooking ("at once" ; with reflection, he might do better), but not you, who boast of wet sea boots and maritime bowline usage.

I understand that you made an erroneous statement, and now you try a desperate contre-attaque, just in case... :) Ok, I will not charge you more for this... :)
1. I did not say that the not-collared loop is a "bowline" (!), or that it is a safe loop to use without a collar, in maritime or any other use ! Read my lips :

I do not expect such a simple two-coils knot to grip the tall "adequately", just "satisfactory well", until it is secured even further by two half hitches, for example. The main idea is to device a mid-line knot that, when tightened, forces the main line that goes through it to bend, to make an L or U turn, so it becomes far easier to block its movement/slippage.
It is expected that those knots are sensible to the width of the bight, the strength of the pull, as well as to the used material.
it [was meant to have] the gripping structure of a "jam" noose. (in the sense of ABoK#1228)

Have you read those words, or lips, of mine ? If yes, you should have realized that your first round of contre-attaque missed your target completely...
So, when you boast of been able to criticize a knot, read the words, or the lips, of the person that presents it, MORE CAREFULLY, and then practice tutorship...

Your flair for drama will win you a photo from me, before I retire.

Thank you very much, indeed ! However, if this "before I retire"  is not yet another figure of speech, in accordance to your flair of drama, I would like something more :

But, again, my point is that stabilization of the knot is more than a during-loading task, in common applications, and the collar is needed for that, in both of these cases.

Again, my point is that the "proper" collar s primary task is to pass the tail through the nipping loop for a second time...and that, incidentally, miraculously, the "proper" collar of the common bowline manages to stabilize this nipping loop, and prevent it from deforming into a helix, WITHOUT any additional structure. In the double, crossed-coils bowline, this goes one step further : the collar is not needed to stabilize the nipping loop at all, which is very well stabilized by itself. Of course, with heavy loading, every part of the knot comes together, and the collar would help the nipping loop from deforming ...but its role in this would only be secondary, because the structure of the crossed-coils nipping loop manages to do this by itself, very well.

So, I would predict that a "ABoK31010, with a loose collar, would hold
...a [common] Bowline can hold, even when the collar is very loose...
...BUT a double, crossed-coils bowline, with a loose collar, would hold MUCH MUCH better ! Is this so hard for you to understand, I wonder... That proves that the role of the "proper" collar in stabilizing the nipping loop is only secondary, in comparison to its role as a means of the tail to be secured by the nipping loop easier. It proves that the collar is a structure of the tail, AND that the security of the tail is the primary purpose of this structure . It is not meant to prove that we do not need the collar, for KnotLand "God" s sake !

You may examine my photo for edification, and then, as you say, "please, correct this erroneous comment ! ".

2. I never said that, momentarily, even the "ABoK#1010" would not hold, especially if it is tied with this ancient, worn out, hardened, rough, eager to retire material of yours... :)  As you said by yourself, with my slippery kernmantle material, you would need magic powers, (and no wind...) to achieve this. If what I have written was indicating such a thing, I have no difficulty to say that I made an erroneous statement ! What I meant is that the collar is, evidently, MUCH MUCH less needed, as a means of stabilizing the nipping loop, in the case of the double, crossed-coils nipping loop, than in the case of the common bowline. Now, in securing the tail from sliping through the niping loop, the collar might even be MORE indispensable in the case of the former, than in the later...because it might turn out that, without any presence of a collar, the single nipping loop - if, somehow, is stabilized by an external means - holds better than the double nipping loop ! So, I am afraid your contre-attaque fired at a decoy, and missed this target as well...
So, do you say that the maximum loads that a not-collared naked nipping loop of a "ABoK#1010" can bear, and a double. crossed-coils nipping loo can bear, ON THE SAME MATERIAL, whatever it is, are even comparable ? If you do, then mail to me those notebooks of yours at once ! :)

I simply stated my familiarity with the knot (which included my first testing, by a then IGKT member).

I have never questioned your familiarity with this knot, as well as with many others. But what exactly was the point of this declaration, which comes times and times again, with so many knots ? I said that "Along with the other dozens of dozens of the knots you devised (?!?)  :) ( nothing earth shattering, you just saw something anybody else could do...and then you have forgotten it, like anybody else could do, too...), it is not a miracle that you have tied this, too...However, you have not understood its importance, not then, not even now, decades later !  :) "
And I said that because the strangeness of this knot has to do with how miraculously well it holds, given its simple structure, and not with the wider curvature of its Standing part ! What you sought in this knot was " making the SPart take a gradual curvature into the knot... [and] had one token of it tested..."(sic). Well, I have seen something else/more, much more important...and tested it with dozens of tokens. Of course, I would nt put anybody on that chair, not even you, with all your Lehudini abilities of escaping criticism and suspended animation... :)

P.S. Nice picture, IN the Wild of your entangled quantum environment...I guess it will take a while to desipher your similary arranged notebooks, so you should start at once !
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 09, 2011, 02:11:47 PM
...a bellringer's loop (i.e., #1010 *de-collared*) bearing much more weight than that empty chair of yours

1. You will be surprised of how heavy is this chair, and how much more load can this knot bear...Of course, I will not put anybody on it, before securing the single-line tail even further, with two half hitches.
2. The Bellringer knot is based upon the stiffness of the double-line tail that pass through the nipping loop. I have not seen a Bellringer knot with a single, flexible and slippery single-line, have you ?  :) The double, crossed-coils loop I have presented, (only as a counter-example of your claim that the collar is needed mainly to stabilize the nipping loop...), this loop IS NOT based on this effect, it can withstand loading even when a single line passes through the nipping loop, and even if this line is flexible and slippery. Big, Huge difference ! If you say that this loop is a Bellringer-type loop, that it is holding with the same mechanism as the Bellringer knot, then I am afraid that you have not yet understood a thing about it...Tie a pair of interlinked loops on the same material, whatever this might be : a single-line Bellringer knot, and a single-line, double, crossed-coils loop, and pull them apart. And/Or, a double-line Bellringer knot, and a double-line, double, crossed-coils loop. You will see at once which loop gives first ! I have done it, with many tokens of pairs of knots with my materials, and it is needless to say that the Bellringer knot was deformed before the double. crossed-coils loop, at all times...However, I have only a collection of climbing kernmantle ropes, so I really can not tell what will happen with stiff anacondas...Try this simple test by yourself, on your material, it takes just a few minutes...and we spear the typewriting !
Any interested reader wishes to see the effectiveness of the single-line, double, crossed-coils loop in holding the tail satisfactory well, in comparison to the effectiveness of a single-line Bellringer loop, is kindly requested to test an interlinked pair of them, and report his findings to us here.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 09, 2011, 05:15:43 PM
Could I respectfully bring you gentlemen back from your delicate exercises in levitation, and ask how this is taking us towards answering the OP  - "What defines a Bowline?..."

The (disputed) 'King of Knots' is not something that teeters on a knife edge of stability.

Are either of you seriously (even for a moment) suggesting that the presence of a turn component is the essence - the 'Definition' of a Bowline?  If not, then please help me understand just what it is that you are exploring...

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: [Inkanyezi] gone on August 09, 2011, 06:11:34 PM
I might have a suggestion regarding the definition of a Bowline type of knot.

We have seen that there are several bowlines, called so, that do not have the same type of nipping loop; it might be a turNip or it can be a half hitch. But there are always two elements present that do not change as much. It is a loop knot, and one leg of the loop comes directly from the nipping structure, while the other goes into the nip, takes a U-turn around some part, whereupon it comes back into the nipping turn once more, by its orientation stabilizing the nipping turn, so that it cannot open any more by forming a more extended spiral instead of a nipping turn. I think the collar is an integral part of a bowline, without it, I wouldn't see it as a bowline.

Then we could see the Myrtle as a derivative knot that does not fulfill all requirements, while the Eskimo Bowline will, as well as the Double Bowline and bowline on a bight.

Then of course we have those simplest structures under that definition, the variations of the proper bowline with just one nipping turn. Even those may be further classified regarding the shape of their nipping turn, whether it is a turNip (round turn) or a half hitch.

But of course, other criteria might be set.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 09, 2011, 07:36:03 PM

The problem is the same old one : Is the collar an indispensable element of the bowline, or not ? Should we define, as "bowlines", all the end-of-line loops that, among other things, have a collar, or not ?
When one tries to answer that question, he has to clarify what the collar really is, so he has to explore what the collar really does. Dan Lehman sees the collar as a means/structure to stabilize the nipping loop, so he is ready to accept other means/structures to achieve the same goal - like the Myrtle collar, for example. So, he is ready to incorporate more collar-like structures into the family of collars, and more nipping-loop-based end-of-line loops into the family of bowlines. Then, it is only natural for him to say that this generalized collar is only a secondary structure of this family, and that we must define "bowlines" without any notion to the collar at all. Indeed, if a collar can be almost any convoluted enough structure around the nipping loop, that helps it be stabilized, one can not but narrow his focus on the nipping loop itself. The generalized collar is lost into the bowline s nub, and what is left, and really matters, is but the nipping loop.
I follow a different, perhaps more naive road. I see the collar as a means/structure of the tail, that helps the tail to achieve its primary purpose, which is nothing else but to be securely attached to the standing part, to form a fixed end-of-line loop. So, for me, the collar is not a structure that was meant to stabilize the nipping loop, but a structure which was meant to help the nipping loop nip / secure the tail more effectivelly. Only incidentally, that same structure, the "proper" collar, manages to stabilize the nipping loop as well, that is, prevents it from being deformed into an open helix. So, the collar is not a servant of the nipping loop, but of the tail. Can we have a nipping loop that does not need the services of a collar ? Yes, we can, as shown by the example of the double, crossed coils nipping loop, that, being so stable by itself, needs the collar much less than the common bowline. When somebody sees the collar like this, he can resist from the temptation to open the Pandora s box, and accept more general forms of the collar, and more general forms of end-of-line loops as "bowlines". The "proper" collar keeps its individual, instantly recognizable character, and, doing this, it is not lost into the bowline s tangled nub : it retains it role as a structure of the tail, independently of the nipping loop. However, because "there are bowlines that hold even with a loose collar, but not with a loose nipping loop", I think that the primary structure of the bowline is the nipping loop, but that the collar is also an indispensable element of it.
So, not having to accept more general forms of collar, because the "proper" collar is so successful in its primary and secondary role without any additional structure, I am not obliged to widen the class of end-of-the-line loops I see/define as "bowlines".
Of course "The (disputed) 'King of Knots' is not something that teeters on a knife edge of stability" !  However, we "analyse" this bowline into elements, as you do, and try to see if those elements are stable by themselves : if they are really individual structures, and if they are indispensable to the compound structure of the bowline. I have tried to show that those two elements I use as building blocks of the "bowline" model, the nipping loop and the collar, are indeed individual elements, and, although they work together as a pair in the final compound knot, they have a clearly separate role to play, and that they can play this role even in the absence of their pair. In the Gleipnir, we have a nipping loop without a collar, and in the double, crossed coils nipping loop, we also have a nipping loop that is very stable by itself, again without the presence of a collar. That means, for me, that the collar is a separate structure of the tail, not of the nipping loop, and its role is to help the nipping loop secure this tail, not to help the nipping loop stabilize itself. Dan Lehman sees the collar as a structure that is helping the nipping loop be stabilized, so he considers many different, more general collars, so he sees the collar as secondary structure. Nobody said that we can have a bowline without a "collar", we both accept that there are reasons that the collar is needed, indeed,  but we are talking of different reasons, and of different collars !  :)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 09, 2011, 07:52:02 PM
one leg of the loop comes directly from the nipping structure, while the other goes into the nip, takes a U-turn around some part, whereupon it comes back into the nipping turn once more

1. Do you think that the other leg of the loop can go into the nipping turn once more, following the same route as when it departed from it, or not ? Should it come into he nipping loop pointing towards the opposite direction it had when it was exiting from it, or not ? In other words, is the Myrtle collar a "proper" bowline collar, or not ?
2. I am not satisfied by this vague "directly"...I like the idea, that throws the Karash loop -and other crossing-knot based loops- out of the bowline family, but how we could quantify it  ? Is the leg of the nipping loop. in the "reversed" Constrictor bowline, coming directy from the loop, or not ? (See picture)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 10, 2011, 05:46:50 PM
The fact that the not-collared, double, crossed-coils nipping loop can hold so well, is an indication that, in the collared, bowline version of the same knot, this nipping loop would not depend very much on the collar, to retain an effective nip on the tail. See the attached pictures for such a loaded loop, where, even if the two coils settle in inclined positions relatively to each other, the "8" shaped nipping loop remains in a closed, functional shape.
There might be many more complex nipping structures, that can be stabilized by themselves like this one, without the help of a collar. This shows that each of the two essential elements of the bowline has an individual role to play, and that both elements are indispensable in the compound structure of the bowline knot.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: WebAdmin on August 10, 2011, 05:50:46 PM
Good day, Gentlemen  :)

I have received a request to move this thread to a more suitable location on the grounds that it is a purely theoretical discussion, rather than a practical one.  Please may I have a concensus of opinion as to the suitability of the Practical board for this discussion's home, as I am loathe to move a long-established 10 pages or so of discussion and good photos without a majority agreement.

All in favour, please post 'aye' for a move to Knot Theory, and all those against please post 'no'.  Justifying your post to the left or the right is purely optional....

Thank you,

Regards

Glenys
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 10, 2011, 07:31:28 PM

The problem is the same old one : Is the collar an indispensable element of the bowline, or not ?
Should we define, as "bowlines", all the end-of-line loops that, among other things, have a collar, or not ?

When one tries to answer that question, he has to clarify what the collar really is,
so he has to explore what the collar really does.

Dan Lehman sees the collar as a means/structure to stabilize the nipping loop,
so he is ready to accept other means/structures to achieve the same goal -- like the Myrtle collar,
for example.  So, he is ready to incorporate more collar-like structures into the family of collars,
and more nipping-loop-based end-of-line loops into the family of bowlines.
Then, it is only natural for him to say that this generalized collar is only a secondary structure
of this family, and that we must define "bowlines" without any notion to the collar at all.
Indeed, if a collar can be almost any convoluted enough structure around the nipping loop,
that helps it be stabilized, one can not but narrow his focus on the nipping loop itself.
The generalized collar is lost into the bowline's nub, and what is left,
and really matters, is but the nipping loop [aka "turNip" ].

I concur in this articulation --well stated.

But I have one expansion, in that "end-of-line [eyeknots]" isn't
my limit; I will (or might, pending further ruminations) include
mid-line eyeknots --well, what of the basic/common bowline
serving so (and, yes, there are those that can be tied w/o ends)?
This all touches issues regarding how *knot* is defined,
vis-a-vis loading (or not) and so on, so I don't want to throw
in a load of other considerations at the moment.

And I remind all that with some greater expanse of examples
to consider, there might be some revisions to current thinking.
I.p., re the Eskimo bowline, surely if one accepts that there
is a distinction of SPart-cores between the turNip and the
crossing knot (aka Munter-hitch form), then it should be seen
that the latter will lay equal claim to this eyeknot.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 10, 2011, 08:25:37 PM
"end-of-line [eyeknots]" isn't [the'] limit; I will (or might, pending further ruminations) include mid-line eyeknots --well, what of the basic/common bowline serving so (and, yes, there are those that can be tied w/o ends)?

I have called the mid-line knots shown in (1) as "midline bowlines", probably for the same reason. ( In fact, they were nothing but mid-line Janus common bowlines - as the beautiful knot presented in the same thread by Dfred was nothing but a mid-line Janus Myrtle loop ...)

This all touches issues regarding how *knot* is defined, vis-a-vis loading (or not)

There are many knots where some small - or even some larger - parts of them are not loaded at all, but those unloaded parts are necessary and functional elements of those knots nevertheless. Their mere presence, in the particular position, into the knot s nub, their mere volume, the fact that the segments of the rope they are made of are incompressible, all those things- that have nothing to do with flexibility and resistance to longitudinal loading - allow those knot to be knots. So, yes, been loaded or not does not make an element of a knot  more or less necessary to the knot...and a "knot" should better be defined without reference to the loading or not of some of its parts.

1) http://igkt.net/sm/index.php?topic=3020.0
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Sweeney on August 10, 2011, 09:17:15 PM
AYE from me Glenys.

Barry
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 10, 2011, 09:58:31 PM
snip...

1. Do you think that the other leg of the loop can go into the nipping turn once more, following the same route as when it departed from it, or not ? Should it come into he nipping loop pointing towards the opposite direction it had when it was exiting from it, or not ? In other words, is the Myrtle collar a "proper" bowline collar, or not ?

snip...

The Myrtle does not have a collar, it has two enmeshed nipping loops.

And what is this "'proper' bowline collar"?  Just because the bowline has a collar, or a nipping loop, does not make these components exclusively 'bowline' components with the inference that any knot that contains either one of them is perforce a bowline.

They are components that comprise the bowline and can be part of any other knot without needing to call that other knot part of the bowline family.  If we start to say that any knot that has a half hitch component is a bowline, then where is the logic that prevents us from defining the bowline to be a Gleipner or a Myrtle etc. etc.

How can it be rational to claim that the presence of a single component defines that knot as a bowline?

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DDK on August 10, 2011, 10:49:25 PM
Aye from me as well Glenys as I could imagine that one might ask "What defines a Zeppelin?" or "What defines a Clove Hitch?"  These could easily lead to the same type of discussion we see here.  These discussions are primarily nomenclature from my perspective and belong in the theory section.

Btw, the joining of two ropes defines a Zeppelin, so, instead of calling the family bends, we will now be calling them Zeppelins in accordance with a possible prime example / archetype for the family.  So, we will have the Hunter's Zeppelin, the Ashley's Zeppelin, the Alpine Butterfly Zeppelin, the Figure 8 Zeppelin, etc.

DDK
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 10, 2011, 11:21:31 PM
The Myrtle does not have a collar, it has two enmeshed nipping loops.

No, the thing you think it is a nipping loop, it is not !  :) It does not have both its legs loaded, as any nipping loop worth its salt :  it is a collar, in the generalized sense, or a hitch.

Just because the bowline has a collar, or a nipping loop, does not make these components exclusively 'bowline' components with the inference that any knot that contains either one of them is perforce a bowline.They are components that comprise the bowline and can be part of any other knot without needing to call that other knot part of the bowline family.

The bowline has a ("proper") collar ( a structure of the tail, tied around the standing part ) AND a nipping loop ( a structure of the standing part, tied on the standing part). If an end-of-line loop has both those things/components, and can be completely untied when those things are untangled from each other, then yes, it is a bowline !

If we start to say that any knot that has a half hitch component is a bowline, then where is the logic that prevents us from defining the bowline to be a Gleipner, or a Myrtle etc. etc.

The bowline is a Gleipnir WITH a collar.  The Myrtle loop is not a bowlne, because the Myrtle collar is not a "proper" collar. If ANYTHING from the "etc, etc" has a nipping loop on the standing part, and a "proper" collar on the tail, and can be completely untied when those two structure are untangled, then it is a bowline. Those three characteristics do not prevent us from defining something as a bowline, they oblige us to define it as a bowline !

How can it be rational to claim that the presence of a single component defines that knot as a bowline?

It is the ONLY rational thing !  :) The presence of those three (3) characteristics, the two components ( nipping loop and "proper"collar) and the condition that the nipping loop structure is topologically equivalent to the unknot, define a knot to be a bowline, indeed. Nothing more, nothing less is needed.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 10, 2011, 11:37:40 PM
Btw, the joining of two ropes defines a Zeppelin, so, instead of calling the family bends, we will now be calling them Zeppelins in accordance with a possible prime example / archetype for the family.

Unfortunately perhaps, the "joining of two ropes" is not a sufficient condition to define a Zeppelin bend. (The Zeppelin bend is a rope-made hinge, the first bights are not interlinked, etc etc ) But every knot that is similar to the Overhand knot, instead of calling it with another name, we are calling it as an overhand knot, double overhand knot, etc, aren t we ? The same happens for fig 8. knots, because the archetypal figure 8 knot helps us define any knot that is similar to it, as a fig. 8 knot...The same happens to the "Crossing knot", to the "Gleipnir", etc etc.
If that ""argument"" was the reason you "voted' as you did,  I can understand it... :) :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DDK on August 10, 2011, 11:48:15 PM
Btw, the joining of two ropes defines a Zeppelin, so, instead of calling the family bends, we will now be calling them Zeppelins in accordance with a possible prime example / archetype for the family.
Unfortunately perhaps, the "joining of two ropes" is not a sufficient condition to define a Zeppelin bend.  . .

The Zeppelin is a prime example of a bend, is it not?.  So, in accordance with the proposals I have seen for bowlines, we should use the name Zeppelin in the naming of the family for which it is a prime example.  I'm not saying that I think this is a good idea.  I'm just extrapolating (yes, and exaggerating for the purposes of making the point) what I have seen suggested for the "Bowlines".

DDK
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 11, 2011, 12:33:31 AM
The Zeppelin is a prime example of a bend, is it not?.

It is not ! The Zeppelin bend is a rather isolated interlocked-overhand-knots bend, I would even say a unique example of this family. None of the 7 well known interlocked-overhand-knot bends are really similar to the Zeppelin bend, and that is due to the fact that all these bends are retucked Reef-like bends, UNLIKE the Zeppelin bend...( See (1)),(2)) You have chosen as an example the only bend you shouldn't  !  :)

As you know, people nowadays are making words, even verbs, from companies that offer a specific product ! You can "google" some words, "xerox" the results, and then read them to see what I mean...:) Is the "bowline" your biggest problem ?
Your argument is completely wrong, for yet another reason. It is reasonable AND useful for a generic knot to be used as an example of some basic function, and vice versa. The archetypal form of the nipping loop is nowhere so clearly seen, without any additional structure, as in the Gleipnir binder knot. If we call a certain knot structure as a "Gleipnir loop", we all know what we mean, and, moreover, this name helps us understand that we are not talking about something else... Knots with such a long history, and of such an importance, as the bowline, are expected to serve as benchmarks for families of knots that bear some resemblance to them. I really do not understand this name fundamentalism...Is the "bowline" a sacred thing we should leave "unspoiled", away from any other knot that can taint it ? I am a great admirer and user of THE bowline, yet I do not have any problem if, by this name, we call a number of similar end-of-line loops...On the contrary, if the name of a particular knot is used for a family of similar knots, this is a honour, so to speak, to the parent knot, isn't it ?
Anyway, the subject of this thread was not the name, but the "structure. characteristics, topology" of the bowline, and the various other similar bends were used only to test the proposed definitions of the bowline.

1) http://igkt.net/sm/index.php?topic=3196.0
2) http://igkt.net/sm/index.php?topic=3251.0

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DDK on August 11, 2011, 03:28:28 AM
The Zeppelin is a prime example of a bend, is it not?.
It is not !  . . . You have chosen as an example the only bend you shouldn't  !  :) . . .

Oh, my mistake.  I kind of like the sounds of the Hunter's Alpine Butterfly better anyways.  :D

DDK
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 11, 2011, 04:56:09 AM
to Theoretical have intruded here,

I here vote YES : i.p., I think it important that the "Theoretical..."
forum have such activity, and not be thought of as so removed
from things practical (aspects & considerations of ...).

Currently, Practical is highly active, of our well-divided lot;
Theoretical too much ignored.  Our considerations here go
to how we conceive & treat & think about practical knots,
and not to the practicality/use of them, per se.
.:. It is fine that this active, engaged discussion vitalize
the Theoretical chambers --we do have such thoughts,
about our knots!  (And we have some currently quiet but
of continuing interest threads there re nomenclature,
which this can see informing.)

:)

(And, having moved (or knot), the Vote msg.s might best be
deleted.)

PS:  Some time ago a thread was deemed to practical for
the Theoretical forum and thus moved ...
INTO CHIT-CHAT ???  ?!  HUh, I voiced dismay at this before,
and will do so more visibly now; that thread, launched by the
right rationale, belongs HERE.
(We might regard the two moves, now, as a sort of trade.)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: [Inkanyezi] gone on August 11, 2011, 07:56:12 AM
My vote also is Yes, as I all the way thought this was a theory discussion.

Then on the continuation, about "proper", I used it only to denote a particular part of the very knot we all know as a Bowline, the "right-hand" one, somewhat distinct from the Dutch Navy, Cowboy, Bowline. Of course other designations might be preferred, but we are on a nomenclature discussion, and it could help to be clear. So it is only a matter of definitions, not a semantic one denoting qualities.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on August 11, 2011, 09:27:52 AM
Theoretically, I think it should be put into" Knot Theory", but, in the end it makes no difference to me. The discussion will continue.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 11, 2011, 09:36:00 AM
"end-of-line [eyeknots]" isn't [the'] limit; I will (or might, pending further ruminations) include mid-line eyeknots --well, what of the basic/common bowline serving so (and, yes, there are those that can be tied w/o ends)?

I have called the mid-line knots shown in (1) as "midline bowlines", probably for the same reason. ( In fact, they were nothing but mid-line Janus common bowlines - as the beautiful knot presented in the same thread by Dfred was nothing but a mid-line Janus Myrtle loop ...)

I thought that we had established early on that a fundamental part of the definition of the bowline is that it is a loopknot.  Indeed, this is such a fundamental, we hardly have a need to reiterate it.

Now you are offering us your newly coined term "midline bowlines", and an image to go with it - vis.

(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=5656;image)

The orange cord shows an end, so that can't be the 'midline' part, leaving the white cord as the aspect the 'midline' must be referring to.

But the white cord only has a Half Hitch Component, and this is stabilised by a Bight Component and a Janus tuck (i.e. opposing Bight Components) from the end of the orange cord.

There cannot be a loop in this construction, so how on earth can you call this a bowline, ignoring the simplest and most fundamental part of the definition of a bowline?

It is a lovely knot and we might call it the Janus Hitch - but there is no way, after all the discussion thus far, that you can expect to attach the name bowline to it...

In fact, this is an opportunity to propose to nail one tiny aspect of the definition of a bowline - vis

1.  A Bowline is an end of line [note 1] fixed loopknot {.EyeKnot}
[note 1 - a Bowline may be tied inline on a bight, in which case the bight is considered as an inline device to create a doubled 'end of line' element]

and carry on a little with :-

2.  A Bowline is defined and described in ABoK as 1010

3.  A Bowline construction comprises a load line, a knot, a fixed loop and an end

4.  A Bowline knot has two components, a Half Hitch Component connected to the load line and a loop leg and a Bight Component connected to a loop leg and the end [note 2]
[note 2 - the Half Hitch component transfers load into both loop legs through the turn element and the high nip force generated causes frictional entrapment of the end.  The Bight component acts as the core for the Half Hitch component and stabilises it via its bight collar made around the loaded line]

5.  A Bowline's Operational characteristics are :- ...

6.  A Bowline's Usage characteristics are :- ...

7.  A Bowline's Historical characteristics are :- ...

8.  A Bowline's Aesthetic characteristics are :- ...

9.  ...

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 11, 2011, 09:52:29 AM
... on the continuation, about "proper", I used it only to denote a particular part of the very knot we all know as a Bowline, the "right-hand" one, somewhat distinct from the Dutch Navy, Cowboy, Bowline.

I use the term "common right hand" bowline, for what you call "proper". Of course, the use of the term "proper" here is wrong, because there is nothing essentially different, or improper, in the left handed bowline. Moreover, I do not really know if most people that actually use the bowline, the amateur and/or the professional sailors, do tie the left- or the right- hand bowline most of the times. ( Of course, the vast majority of them do not know anything about ring loading...and the same can be said for the cowboys, or the marines of the Duch navy :))
The use of the term "proper" for the collar of the (left and right hand) common bowline ( i.e the collar where the working end, after its U turn around a segment of the standing part, returns to the nipping loop by the same route, and it enters into it pointing to the opposite direction from the one it was pointing to when it exits from it ) is more justifiable. The "proper"collar, and the Myrtle collar, for example, are indeed very distinctive, as the former manages to stabilize the nipping loop better than the later -without any additional structure-, the former makes a tight loop in and around the nipping loop ( to the degree one can confuse it with a nipping loop...), while the later does not. So I believe that the use of the term "proper" for the common bowline collar is reasonable, but not for the right hand bowline.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 11, 2011, 10:18:28 AM
...The orange cord shows an end, so that can't be the 'midline' part, leaving the white cord as the aspect the 'midline' must be referring to.

My dear Drek, do not waste your reasoning abilities for such self-evident things... :) Better read the f... thread !

But the white cord only has a Half Hitch Component,

There is no "Half Hitch component" there, or any hitch component whatsoever, I can assure you !  :) What your eyes see is only a nipping loop, a bare, naked nipping loop, with both its legs equally loaded. Your mind can see other things, of course... :)

...There cannot be a loop in this construction, so how on earth can you call this a bowline, ignoring the simplest and most fundamental part of the definition of a bowline?
...there is no way, after all the discussion thus far, that you can expect to attach the name bowline to it...

Of course, it is not a end-of-line loop ! Even "I" can see that  :) ! But the structure is identical to the structure of the (Janus) bowline, as both of them have one of the four ends unloaded. The name was pointing to this fact, as this knot CAN NOT be confused with an end-of-line loop ! I though that this name was helpful for one to see how this knot works, rather what this knot look like - it obviously does not look like a end-of-line loop, so there is no danger of any confusion there.
When there was a long discussion about the so-called "Zeppelin loop", that is a loop that BRUTALLY destroys the essence and beauty of the Zeppelin bend, its remarkable symmetry and its rope-made hinge character, I have not seen anybody here say a word...
Anyway, if the name "mid-line bowline" is such a disaster, we can forget it. On the title of this thread, I used the term "midspan bends", and I have introduced the name "midline bowline" very cautiously. Please, suggest something more "proper", but in the "proper" place, the above mentioned thread...  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 11, 2011, 03:44:10 PM

But the white cord only has a Half Hitch Component,

There is no "Half Hitch component" there, or any hitch component whatsoever, I can assure you !  :) What your eyes see is only a nipping loop, a bare, naked nipping loop, with both its legs equally loaded. Your mind can see other things, of course... :)

I demonstrated extensively, back in post 65, examples of the Half Hitch Component with both sides of the hitch loaded. In ABoK Ashley describes 160 and 161 as hitches where the HH Components are made onto rope, again both sides loaded (indeed, were it not for the missing bight component in 160 and 161, they are both bowlines)

(http://doit101.com/Knots/images/fig39.gif)

What you have shown in your image is the Half Hitch Component, 'hitched' to two Bight Components.

(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=5656;image)  You even have it arranged with the crossing legs, rather than the Turn Component the Bowline component morphs into under load.

What my eyes see, and what my definitions describe are exactly as I have stated - A Half Hitch Component made about and stabilised by, two Bight Components.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 11, 2011, 05:51:46 PM

While one can find the fuzzy boundary and similar geometry
between this conceived "(half-)hitch" & "nipping loop" pair,
the former really includes a notion of self-nipping (i.e., of
a loaded end on a tail) in contrast to the latter's absence of
such notion --and put load on the photo'd white rope and
you might see it lose contact w/itself as it *rights* itself
towards helical form.

Of the old-image timber hitch + half-hitch (and, NB, I refuse
to use "Killick" (etc.) here, seeing that as a unified like
structure for a different purpose), the in-question component
for these conceptual constructs.  We must operate with
fuzzy boundaries, here and elsewhere.

And so I don't accept calling the loop-finish to the turNip
base another nipping loop in the first; but, then, I don't
so much care one way or another, in re my thoughts about
grouping a family of such knots as "bowlines", at the
moment --preferring to take the SPart's structure as the
sole or key criterion w/o further precaution.

--dl*
====

ps:  [Really, that supposed counter-comment about moving
this thread to a less active Decorative Tutorial ought not to
definition/defining-essence of a particular knot,
not about its use, viability, practicality --though it concerns
such a knot as the focal point.  That is the topic; any further
posts that range OT into practical concerns are, well, OT
(off-topic), and should not move anyone to re-Moving.]
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 11, 2011, 06:06:42 PM
ABoK Ashley describes 160 and 161 as hitches

Ashley is wrong there, as in many places, because he is no "God", and you are not His prophet !  :) When you cite Ashley as your "proof", you only show signs of argument weakness...Your other arguments are demolished back in Reply#66 and Reply#73, and I do not want now to raise clouds of dust from those ruins again... :)

When a loop (around a line or a pole) has both its ends loaded, it is not a hitch, it is a nipping loop.

What you have shown in your image is the Half Hitch Component, 'hitched' to two Bight Components.

No, of course not. The white rope forms a clear, bare, naked, archetypal, Gleipnir-like, NIPPING LOOP !

When a loop (around a line or a pole) has both its ends loaded, it is not a hitch, it is a nipping loop.

P.S. The funny thing is that you "see" a hitch, where there is only a nipping loop, but also you "see" a nipping loop, where there is only a hitch  :). You describe the Myrtle "generalized" collar / hitch as a nipping loop !
"The Myrtle... has two enmeshed nipping loops."(sic)
Derek, sorry my friend, I was wrong...You do not need a chair, you need a new pair of glasses !  :)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 11, 2011, 06:16:25 PM
You even have it arranged with the crossing legs, rather than the Turn Component the Bowline component morphs into under load.

From this comment I understand that you do not know why I have arranged them so...because you have not read (1). I repeat the reason here, so you would not have to push many buttons...

"There is a simple reason for it, that I will try to explain. I wanted a "mid-line bend" that was able to withstand even a lengthwise pull of the attached line, so I made sure that the free end of this line remain as near the point where the ends of the nipping loop touch each other, and as near the axis of the main line, as possible ".

1)  http://igkt.net/sm/index.php?topic=3020.msg18419#msg18419
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 11, 2011, 07:36:42 PM
Theoretically, I think it should be put into" Knot Theory"

The term "Knot theory" means something to all people, except to the members of the IGKT Forum. As we are not sooo many, nobody seems to give a penny about this misnomer...
What you describe as "Knot theory", is probably nothing else than the examination of practical knots as such, without any reference to a specific application. This examination could be the subject of a discussion, and this discussion could help somebody, somewhere, sometime in the near or distant future, to propose a "Theory of Practical Knots". I believe that I will not live enough to learn the first such theory... :)
So, the real distinction is between "Applications of Practical knots" and "Characteristics of Practical knots", to use the first quasi-real descriptions that comes to my mind. The distinction between, from the one hand, a section of a non-existing "Theory of Practical knots" ( sorry, the term "Knot Theory" for this makes me laugh, so I can not type it...), and, from the other, a "Practical Knots" section, is absurd. Of course, there will always be people that fear, so hate anything has to do with theory of anything, so those people will not care if the term "Knot theory" means something else to all people on Earth but them...and if there is not any "Practical Knot Theory" to anybody s mind, and if, by the term "Practical knots", everybody should mean something more than "Applications of Practical knots"...
Is it a matter of "vote" ? Of course not ! Vote means something very valuable, lives were sacrificed for this right to be conquered by the members of a unified group of people, ready to die for their city, for each other, and from any possibly wrong consequences of their decisions. What is described here by "vote", has the same relation to the true vote of citizens, as "Knot theory" has to the knot tyers...i.e, none whatsoever ! :) People confuse vote and the decisions of the citizens of democracy, with polls and opinions of the spectators of mass media...And when they do not really know what to do, they start counting... :) The advantage of such an attitude, is that one can even fall asleep, using this wise ancient method !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 11, 2011, 10:57:42 PM
"Sneeze!"
Now watch kiddies as the nice (wo)man uses a ton/tonne of bandwidth to respond. :D

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 12, 2011, 12:21:24 AM
snip...

P.S. The funny thing is that you "see" a hitch, where there is only a nipping loop, but also you "see" a nipping loop, where there is only a hitch  :). You describe the Myrtle "generalized" collar / hitch as a nipping loop !
"The Myrtle... has two enmeshed nipping loops."(sic)
Derek, sorry my friend, I was wrong...You do not need a chair, you need a new pair of glasses !  :)

Oh Xarax,  yet again you are so wrong...  Indeed I need glasses - but I ALSO need a chair, for this process is so tiring...

But I think perhaps I can see (with my new glasses perched jauntily on my nose) what it is that is leading you away from understanding what I am attempting to communicate.  I think that you are getting hung up on a name.

When I first started to explore the components of a knot (as many more before me doubtless have), I chose names for the components that I had identified based on what I thought they looked like and what I felt they did.  But they were just names that I chose like the Simple Hitch Component and the Half Hitch Component.  These names are causing you problems because of your fixation with what you see these names as meaning.

If however, I had chosen a name such as the 'Morphing Overlaid 180degree Helix Component', you would not have the same preconception and might be more predisposed to accept the component for its function rather than by what you see the name as suggesting from a fixation with terms such as 'Hitch' or 'Bend' etc.  But you need to forget these old words - 'Bend' after all is such a ridiculous term for a connecting knot.  I predict that you and I may well live long enough to see the demise of mess we presently have for naming our knots as the next generation of Nodeoligists cleans up the mess of ages.

Try to see beyond your preconception - make up your own names for these components - and build from that.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 12, 2011, 08:58:33 AM
yet again you are so wrong...
You too !  :)
I ALSO need a chair, for this process is so tiring...
Me too ! And, sometimes, I need that chair you have e-mailed to me !  :)
I think that you are getting hung up on a name.
Most probably...because you hanged it around my throat ! We should better use symbolic notation, or entirely other words, that do not bear within themselves memories/meanings of familiar things.
I chose names for the components that I had identified based on what I thought they looked like and what I felt they did.
Wrong choice ! As with women, one should be careful how he calls them...Knots are jammed in our mind, we can not forget them !
My real objection is that you choose names for the components according to what they look like, not what I feel they do ! When I read/ hear the word  "Hitch", I have in my mind a certain function, which is the miracle of an inanimate thing, that somehow manages to keep one of its leg free of tension, while we pull the other as hard as we can ! I follow the flow of tension into its body, and I wonder, how on earth this flow disappears after a certain rope length ? And here you come, and you destroy all that, naming "Hitch" something that allows this flow to pass through, from the one leg as well as from the other ! You twist the hitch s arm and my mind !
But you need to forget these old words
Oh ! I am too old to forget old words, and to learn new ones ! Why you insist to use those words, and run the danger to induce confusion against your will, and do not use other, neutral, safe, abstract words instead ? You need to use other words!
Try to see beyond your preconception - make up your own names for these components - and build from that.
The misconception of names was all yours ! You could well have chosen other names, define their meaning carefully from the start, and spear us the typewriting ! It is you who proposes an abstract scheme - so needed - for the explanation of knots, not me. When I have attempted something like this in a smaller scale, and far less ambitious, I used old names of things to describe just those things...like "nipping loop" , or "riding turn", names that instantly drive the reader to the correct object, and only afterwards attempt to push him a little forward from the familiar place...You take a name that means something very specific, and you pull it from every side of it, and make it large enough to cover new areas...This in not a generalization, this is an ignorance of the laws of language, which, my dear Derek, "does not have bones, but it crushes bones..." Language should be respected, it is the great tool of humanity to reach the meaning, and to explore the world. You are not allowed to use words that mean another thing, for something else ! A hitch is a hitch, for KnotGod s sake, and a nipping loop is a nipping loop !
I believe I am one of your most devoted students, commited to this valuable endeavour to clarify things, to explain things, to reduce the apparent complexity of the KnotLand to something more fundamental, essential, and to open the road for the new generation of knot tyers, to the Holy Grail :  A true "Practical Knot Theory" ! As a teacher, you are the one that bears the burden to use the most smooth, easy, step-by-step method ...and what you are you doing ? You insist of playing with our minds, of forcing us to speak familiar words while thinking new meanings...I do not blame knot4u, and the other young guys, that they come to hate our guts... :) They do not wish to speak the language you wish them to learn, they do not wish to twist their minds, simply because they have better things to do !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 12, 2011, 10:10:06 AM
I chose names for the components that I had identified based on what I thought they looked like

That is our main difference. You name things based on how do they look, to the knot tyer as a spectator, I try to think of things based upon what they are, to a knot tyer that is part of the rope itself ! I imagine I am the rope, and I am pulled and twisted by you, the knot tyer...Which parts of my body will fell something, which something else, and which nothing at all ?
This is called an "intrinsic" description of the object. You do not see it from outside, in fact you can not see it from outside ! You only follow the flow of forces, you put yourself within the rope, and you try to imagine what the knot really is, and how it manages to be what it is...It is like when we speak about curvature of the surface of a 2D object : You can see the surface of the object from outside, from your flat 3D world, and decide if it is curved or not, and how it is curved. But also you can do the same thing, AND MUCH BETTER, if you are inside/on the surface of the object, if you belong to its 2D world, and measure the curvature from there, and from there only. You just have to follow a circle, and to measure the length of its perimeter and its radius. If the ratio is 2π, the surface you are on is flat, if it is greater or smaller than 2π, the surface is curved in the one or the other sense.
When I am inside a loop, and one of my legs is pulled ferociously by you, while the other is free, because I was clever enough to put it underneath the one pulled, and to secure it so, I know I am part of a hitch, I am a "hitch component". When both my legs are pulled at the same time, and I can not cross them, but the only thing I can do, is to constrict the object (line or rope) that pass through my hug, then I know I am a nipping loop, I am a "nipping loop component". I do not have to be in your position, to look to myself from outside, to decide what I am ! I only have to measure things from my world, the world of the tensioned, curved, twisted rope...
So, when I am in the bowline, I know that I am a nipping loop and not a hitch, because the standing end and the eye leg of the standing part pull both my legs, and the only thing I can do is to squeeze the two legs of the collar that happen to pass through my hug...and I do not listen to you, that keeps telling me I am a "hitch component" ! I know better than you what am I, because I am there, into the flesh of my body, while you are only outside it, a poor spectator of my skin... :)
I have not suggested to you to buy a new pair of glasses, just to "see" the skin of the knots...but to read what you write,  :),  and "see" better through this skin, the flesh of the knotted ropes ! In the common and Eskimo bowline, there is no hitch present, only a nipping loop, and a "proper" collar. Any hitch component worth its name should have managed to have the one end/leg free, otherwise it is a - more or less successful - nipping loop. And I am saying this, because, if this nipping loop is twisted more than a certain degree, it becomes a "Crossing knot Component"  :) :), and it becomes less strong in its gripping power on the tail.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 12, 2011, 12:32:12 PM

Oh ! I am too old to forget old words, and to learn new ones ! Why you insist to use those words, and run the danger to induce confusion against your will, and do not use other, neutral, safe, abstract words instead ? You need to use other words!

Indeed I do, and my lesson is, I hope, well learned.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 12, 2011, 12:51:13 PM
I don't so much care one way or another, in re my thoughts about grouping a family of such knots as "bowlines", at the moment --preferring to take the SPart's structure as the sole or key criterion w/o further precaution.

So, according to this view, what is a bowline ? An end-of-line loop that happens to be fixed, when we manage to stabilize a TIB nipping structure tied on the standing part - so it does not deform into a helix, and does not "walk" down to the tip of the loop. The ancestor of Dan Lehman figured out that he could not attach the tail on the straight tensioned line of the standing part ( he had not yet discovered the climbing friction hitches, and the ww hitch...), because any straight tensioned line is very smooth, very slippery... so what does he do ? He makes a standing part segment a little less straight, a little more curved, a little more convoluted, so his tail will be stuck on a obstacle, and will not slip alongside the standing part. He tries a simple turn, and he tries to make this turn stay as it is, and where it is...that is, not deform into a straight line again, and not revolve and walk down towards the tip of the loop. Trying all the possible ways to achieve this, he passes the tail through this curved standing part structure, he passes it around it, over and under it, anyway he can. The "proper" collar is not but one of the possible such solutions, but there are many others. So, all those solutions to this problem, the stabilization of the nipping structure in its form and its position on the standing part, are "bowlines".
My ancestor was thinking otherwise. He has this end, the tail, and he tries to fix it on the standing part. He encircles it with the standing part, with the hope that this embracing will be enough, will grab the tail and he will not need anything else...Nooope ! His tail slips through the nipping loop, like his wife from his hug...so what he does ? If once is not enough, try it twice ! ( With women, one has to go to bigger numbers, of course...  :)). He passes the tail another time through the same loop, driving it along any route he could think of. So he ties a Myrtle loop, a common bowline and an Eskimo bowline. Then, he chooses the bowline, simply because this solution is holding better than the others, without any additional structure. The problem of stabilization of the nipping loop did not even crossed his mind, because he sees the whole problem as a problem of attaching the tail on the standing part, and he makes the standing part turn around the tail to achieve this, to grab the tail with a tight hug. He was lucky, because his solutions managed to stabilize the standing part structure at the same time they were nipping the tail sufficiently well. And the simplest and best solution to his problem, was the bowline, and the bowline s "proper" collar that passes through the same point inside the hug twice, following the same route.
See the attached picture, for a Dan Lehman s ancestor "bowline". This ancestor tried a 8 shaped curved segment on the standing part, and then he passed the tail through it in the simplest way, in an attempt to fix the standing part s structure in its form and position. The interested reader will recognize this deformed, double, crossed-coils loop, with a Myrtle collar.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 16, 2011, 06:30:41 PM
I chose names for the components that I had identified based on what ... they looked like

That is our main difference. ...  I try to think of things based upon what they are,
to a knot tyer that is part of the rope itself !

[E.g.,]  When I am inside a loop, and one of my legs is pulled ferociously by you, while the other is free,
because I was clever enough to put it underneath the one pulled, and to secure it so, I know I am part of a hitch,
I am a "hitch component".
When both my legs are pulled at the same time, and I can not cross them, but the only thing I can do,
is to constrict the object (line or rope) that pass through my hug, then I know I am a nipping loop,
I am a "nipping loop component".

...

What is a clove hitch when tied around a stake as part of a sort
of *fence* line, ends running opposite directions to adjacent such
stakes, and so on?

What is the same structure when tied tightly around a coil of rope,
to bind it, ends limply hanging (tension all within  the *knot*)?

Quote
A hitch is a hitch, for KnotGod's sake, and a nipping loop is a nipping loop !

And ... in between ..., or simultaneously ... ?!

What is the debated component of the Myrtle eyeknot  when it is
extended to make a "proper collar"?
(Which knot is, in my naming from some decade back, a BowlinaBowl.   :D  )

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 17, 2011, 01:27:23 AM
What is a clove hitch when tied around a stake as part of a sort of *fence* line, ends running opposite directions to adjacent such stakes, and so on?

We would call a hitch pulled on 1 leg as open, and with both legs as closed.

It is a "closed"  hitch, which, to my view, is indistinguishable from a nipping loop.

What is the same structure when tied tightly around a coil of rope to bind it, ends limply hanging (tension all within the "knot")?

I am sure you have tried hard to discover this case... :)
I would say that it is a compound knot : two half hitches connected together.

A definition is never a 100% accurate/complete description of an object, or of the 100% of the to-be-defined objects. We are trying to define/classify as many things we can, with as few words as possible, nothing more -ambitious- than this ! Some small fish will go through any net...
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 17, 2011, 05:34:59 AM
What is [a clove h. ] when tied tightly around a coil of rope to bind it,
ends limply hanging (tension all within the "knot")?

I am sure you have tried hard to discover this case... :)
I would say that it is a compound knot : two half hitches connected together.

Ha, the case has been there all along, waiting for our
attention (like so many knots await ...).  I think your
answer is more inventive than my question --you must
have lowered that chair and had a good sit & think in
it.   :D

Which exercise is good, for I have further questions (noting,
though, that my last of the above post remains unanswered
--Myrtle-extended is calling you ... ).

What is a simple turn (that thing sometimes views as
a "nipping loop" or a "hitch") of your orange rope run
through the turNip of the white rope, so to stabilze
that structure, and held in its tension by the turNip ?!
You can't call THIS any compound whatever --I've trimmed
it to the minimum--; and with limp ends, it fits neither

(Maybe it's a "small fish"?)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 17, 2011, 11:52:38 AM
What is a simple turn (that thing sometimes views as a "nipping loop" or a "hitch") of your orange rope run through the turNip of the white rope, so to stabilize that structure, and held in its tension by the turNip ?!
You can't call THIS any compound whatever --I've trimmed it to the minimum--; and with limp ends, it fits neither of your above-cited alternatives.

Easy ! It is the same kind of thing that stabilizes the genuine Bellringer s loop ( not yours, the ABoK#1010 de-collared), the Bellringer s loop with a SECOND, unloaded line that passes through the nipping loop, just to make the two-segments longitudinal element stiffer ( We meet the same thing in the Sheepshank, the ABoK#160 and #161, etc..). One or more segments of a rope can be used by a knot, even if they are not loaded by themselves, in the following sense :
There are many knots where some small - or even some larger - parts of them are not loaded at all, but those unloaded parts are necessary and functional elements of those knots nevertheless.. [by] their mere presence, in the particular position, into the knot s nub, their mere volume, the fact that the segments of the rope they are made of are incompressible

I am sure that many knots, and many things about knots, are awaiting somebody else to look at them more carefully than I manage to do...Practical knots Theory is not born yet, I believe, and I am not pretending "I" know any "deep""truth"  that should be carved in stone and last for centuries ! I only try to use some simple, sometimes naive notions that might help me not get lost into the combinatorial nightmare of all the possible knots. I prefer this simple minded attitude, from the other alternative :  In KnotLand, there are everywhere grey areas, nothing is black and white and as simple as it looks, definitions are impossible, every knot is a different immensely complex machine, knots are something, and, at the same time, simultaneously, something else in between... Of course, the second component in Fig. 39 of Derek Smith is not a clear- cut nipping loop, and/or a hitch, and/or whatever, and the "Myrtle extended" might be a knot element that belongs to more than one worlds/words/definitions. Are those smaller or larger fishes going to persuade me stop fishing, and start eating fast-food made by the knots-as-tools-and-nothing-else "users", or canned-food made by some prophets and preserved into century-old sacred scripts ? No, I do not thing so... :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: WebAdmin on August 20, 2011, 10:30:17 PM
Good day, gentlemen.

To respond to the various points raised by my question over the placement of this thread:

- Voting discovers the proportional will of those eligible and willing to vote.  Those unwilling but eligible lose the expression of that will.

- An assessment of the answers shows 5 ayes, plus the original requester, 1 which I don't quite understand, and everyone else abstaining after a reasonable period of time.

- Out of 176 replies, I don't think the 2 purely relating to this move interrupt the flow greatly, and are not really worth deleting.  Other replies are contained as part of longer posts.

- The stated purpose of the Theory Board is that it is a discussion board "For those who want to get the knot between their teeth and shake it apart, either figuratively, or binarily."  I gather from the foregoing 12 pages of discussion that you gentlemen have certainly been doing that with this thread.  Therefore, that seems the most appropriate place for it to go.

The pantechnicon is booked......  safe travelling, gentlemen.

:)  Glenys

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 21, 2011, 05:30:14 PM
- Out of 176 replies, I don't think the 2 purely relating to this move interrupt the flow greatly,
and are not really worth deleting.  Other replies are contained as part of longer posts.

...
Therefore, that seems the most appropriate place for it to go.

Except for someone who would not get along with this, who must remove
his numerous posts so that after the above writing the count became only 108
--68 deletions are what he was willing to pay ... if he cannot get His way!

>:(
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Wed on August 21, 2011, 06:17:19 PM
Yet again, the value of keeping things, and in a chronological order as well, rears it's face. Now things are jumbled up again. But my post is probably more suited in "Chit chat".
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 21, 2011, 08:58:50 PM
what he was willing to pay ... if he cannot get His way!

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 21, 2011, 09:33:09 PM
I guess such petulance can't be trusted in the future and we must quote anything he says in order to safeguard against

I guess such petulance in moving a thread after 89 (!) posts to where it does not belong, can t be trusted in the future, and I should not say anything that, next time, can be buried somewhere deeper in the Forum... :)

[are'] all the images that Xarax uploaded still available

I have all the pictures, but they have nothing to do with "Knot theory" and/or "Computing", I am afraid...And 5.000.000 to 1 "votes" :) can not change this ! I would be glad to post them wherever they will not be deleted, AGAIN, (like the previous time...), or moved where they do not belong (after 89 posts ! ), when somebody decides that the thread is "very" long, and orchestrates such a lamentable "vote", with a 5 to 1 outcome ! I guess such petulance can not be trusted... :)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: WebAdmin on August 22, 2011, 10:27:02 PM
Gentlemen,

I didn't post the request for opinions elsewhere because it was not about anything else - it was about this post.  So I believed that this was where I should post about a request to move it: where those whom it would most seriously affect would be able to see it and comment on it, without confusing those who were not involved in the discussion.

I didn't see any clearly stated objections apart from those mentioned in my previous post.  And, I have tracked down the reference to a mis-moved post: it occured when I was in trying to work in a rush, and was subsequently unable to get back on to the forum for the next 3 months.  Consequently I missed Dan's message alerting me to my mistake.  I apologise, and thank you, Dan, for trying to bring it to my attention.

I don't have the ability to backup, that has to be done by Mel herself, and I have emailed her to find out if the thread is retrievable.  Of course, if Xarax would reinstate his posts, then they would retrieve the thread themselves.

Just in case anyone is not sure of what I'm trying to explain, since they've joined the forum since I was last on: I'm Glenys, I'm the WebAdmin, it's my role to act as a liaison between those wanting to post stuff on the site or forum and the WebMistress, who is Mel.  Mel has kindly replied directly to posts in the past, but I know her business responsibilities have increased in recent months, and she may not have so much time to respond quickly.  I have limited access to website/forum utilities, and I am neither tech-literate nor do my knot-tying opportunities ever have opportunity to progress beyond basics, because my family life is too busy.  I can't join in discussions such as you gentlemen have, simply because they are too far above my level of knot education.

Xarax - please would you reinstate the posts you have deleted?  If that is not a facility available to you (I've never had to try it, so I don't know if it can be done from a non-administrative membership) then please let me know and I will work with Mel to do it for you.

Thank you

Glenys
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 23, 2011, 01:41:11 AM
I appreciate the polite tone of the previous post, which is something that can solve the most tightly jammed issue, I believe. So, let me restate some things I have already tried to point out in two previous replies, in vein...

I can only guess it from the following revealing text :
I'm not knocking the long discussion on this Forum about the definition of a bowline, but that sort of discussion could be a real turnoff for a newcomer !
I wish I am mistaken on this, of course...

2) In the first request for the infamous "vote", the Web-administrator was cautious not to express any personal judgement about the heart of the matter :
"I have received a request to move this thread to a more suitable location on the grounds that it is a purely theoretical discussion, rather than a practical one."(sic)
Then, after the so-called "votes" were cast and counted, ( by the way, not a very difficult job, taking into account the fact that the "votes" were 6 (six) !  :)), the tone was changed :
"I gather from the foregoing 12 pages of discussion that you gentlemen have certainly been doing [Knot theory and Computing] with this thread.  Therefore, that seems the most appropriate place for it to go."(sic)
So, now after 176 (!) posts, 12 (!) pages of replies and 40 (!) days , and been equipped with this cataclysmic 5-1 result...the Web-administrator finally made up his mind, and decided that this thread was really off-section ! I thank the Web-administrator for all the laugh that this prompt action offered to me !  :)
The action should have taken place right after the first days and posts, without any help/excuse of any "vote". If the opinion of the participants of the discussion was needed, they should have been asked for it, but they should not made responsible for any decision, which is in the absolute power and responsibility of the Web-administrator - whatever the outcome of the "counting" of any such opinion poll. I have the courage to express my opinion, even if it is the 1 of the 5.000.000 opposite opinions, and so I expect/demand the person who has the power and the responsibility to move or remove my posts, to do the same ! The hypocritical-like "voting" was forced without any reason, and it should have stopped right after it was stalled to this lamentable 5-1 result, of which we should be ashamed !

3) There are people that have an altogether narrow view of knotting, and believe that the "Practical Knots" section should refer only to applications, uses, of practical knots, and not about the practical knots themselves, their form and their structure.  Any discussion about a knot, however "practical" this knot might be ( and there is no knot more "practical" than the king of knots, the bowline, of course...) seems to those people a waste of time, a waste of valuable bits and bytes, and a danger to new registrations by newcomers. Now, if this discussion is short lived, like most of them are, they just ignore it. However, if it starts to be really interesting to some people, and generates many replies, they start to hate it, and try to de-evaluate it by all means, ridicule it, etc.. I have been the victim of such behaviour. not one, not two, but many times...Some members of the forum translated and posted their "comments" in my native language, for me to understand it ! Of course, I have not seen any Web-administrator noticing this racist behaviour.
I refused to obey to this attitude then, and I will never obey to this attitude ever. If this will be forced on my posts by some pre-fabricated "majority" of 5 or so people, let it be, but I have the right to delete any of my posts, before they will be deleted or moved or removed by others. without any reason given and against my will, as it has been done already in the past !
The truth is simple: There are horses for courses. Knot tyers that prefer to solve problems using knots as tools, and knot tyers that prefer to study the knots themselves, their structure, their form, their function, trying to improve those tools. This has nothing to do with any "Knot theory", which is a theory of the mathematical, not the physical, not the practical knots. The "Practical Knots" Section could have been divided into those two sub-sections, the "Applications of Practical Knots" sub-section, and the "Structure/form/function of Practical Knots" sub-section. Both are indispensable for the promoting of knotting, and should be respected equally.
So, unless this distinction is not implemented, or both of those sub-sections are not considered as part of the existing "Practical Knots" section, as it was supposed to be till now, I do not wish to post anything under the misleading "Knot Theory" section, and diminish the "Practical Knots" section. Needless to say, if my opinion -of what is worth- was asked, I would have had no doubt whatsoever where the "structure and characteristics of bowline" thread belongs ! However, I was not asked about it...I was asked to "vote" if it should be contained in the "Practical Knot" section ( Of course it should ! ) or in the misleading, non-existend "Knot Theory" section ( Of course it should not !) .

4) When 68 of my posts, which I spend so much time to write _ and, not having adequate access to the language, I spend much more time than the other members of the Forum to express myself ...-, when all my pictures of the knots, which I spend so much time to explore, tie, shoot, select the better of them, convert them to a white background, reduce their size...-when all this work was moved by the 5-1 "vote" under a misnomer "Knot Theory" section, , I said, enough is enough. However, I made a copy of them, and kept them in a file, just in case a member of the discussion wished me to send them to him. And then, just as it had happened the other time, there comes the usual suspect, the self appointed advocate of the "authority"/majority", with his carefully chosen vitriolic style :
...someone who would not get along with this, who must remove his numerous posts --68 deletions are what he was willing to pay ... if he cannot get His way!
>:(
In short, I am some kind of "raving lunatic"(sic)  AND a masochist, too,(!) that is willing to spend a month of his short remaining life, only to delete it afterwards, to impose HIS way ! One easily gets mad >:( with this - what was probably the real intention of the author of this envious "reply" - and pushes the delete button at once ! So, I deleted  my copy of the thread with all my 68 replies....and I have regretted this now, of course...I only managed to save some pictures, that I had filed in another folder. If I had my replies, I would have posted them to the Web-administrator, because I have a soft spot of polite manners, even coming from people who had treated me so wrongly and unfairly in the past.
I do not believe that anybody really wishes to have this discussion go forward, but me... Judging from the number of visits at the attached pictures, I have not seen any interest in the pictures of the "8" shaped bowlines, or the double.crossed coils bowlines, I had spend so much time to explore, tie, take pictures of, etc.. People just wish to learn how to escape from a prison, using two sheets - not with the Count-of-Monte-Christo way, of course... :) Anyway, I have learned a lot by trying to express my view on this thread, and I would love to participate in a new dialogue that could take place somewhere in the future....(if my participation is of any worth, or asked by anybody...) - in a proper "Practical knots form/structure" section, next to the "Applications/uses of Practical knots" section !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on August 23, 2011, 03:01:28 AM
I for one would love to have copies of the fruits of your labors xarax! The thoughts of all your Work going into the netherworld of cyber malfunctions gives me the chills, severely!
Might be a great backup for me to have copies. ;-))

I had been finding this particular thread very enlightening and it had been broadening my own understanding of the forces created and encountered within practical knots, all of them, regardless of application(s).
The greater the understanding of the inner workings, the better one can apply them. And more safely too!

I fear that this move to "theory" will obscure the learning to be had by the "newtimers".

I sincerely hope that the train (of thoughts) have not been derailed.

Hmm, I wonder if this could be moved back?

SS
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 23, 2011, 05:36:41 AM
I am soooo idiot, I had deleted the copies I had made of all the thread, because of this Dan Lehman s vitriolic "reply" above, where he portraits me as some kind of a selfish person AND a masochist, at the same time...a selfish mazochist who finds great joy in destroying his own 40 days 68 posts effort, just because he wants things to be done his way...I wonder, whose way those things were done, at the end of the day....because that was not my way, that is for sure ! If Dan Lehman is soooo happy that the thread is buried, at last, in the "Knot Theory" section, and my replies to him were lost because he managed to drive me mad AGAIN, I conclude that I was right from the beginning...in that the "proper" collar is an indispensable element of the bowline, and that this collar is not needed to stabilize the nipping loop, but to secure the tail...even if his highness manages to move this thread to the other side of the moon !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 23, 2011, 08:14:20 AM
because of this Dan Lehman's vitriolic "reply" above, where he portraits me as
some kind of a selfish person ... [who deletes all his posts!]

Go spit in your mirror at that "vitriolic" [sic] image of hate you fancy.

The request to move this thread was NOT made (or known) to me.
The matter was put to vote of those interested --apparently a small
number at the point of decision (judging by views of images, too),
and the move made with a 5-1 (& X. not in favor though refusing
to cast a vote --since he "knows better ..." [sic]).  (Derek voted against,
but so far hasn't thought to delete his posts to show how much he knows.)

Quote

This is a curious and judgemental [sic] (and have some more "[sic]"s,
as I'm sure you must be running low on them by now) view of this
(sub-)forum.  One might otherwise think that the thread will continue
with what activity it had at the time of the move --noted to be among
a few--; and it might enliven some of the other threads started here
but left idle too long, re nomenclature.  Either place, "a rose by any
other name, will smell as sweet" (for those who care to "stop and smell
the flowers").

Quote
The thread was about the structure, form and function of a practical knot
- indeed- of THE practical knot- and not about some specific application or use
of this knot in solving  a particular knotting problem. This is a distinction which is real, I think,
...

No, not immediately/directly.  Rather, the topic is about how to
classify "bowlines", which is more a philosophical (hence, "theoretical")
investigation --to wit (from the OP):
but no one coherent body of theory that defines a Bowline.
|  So this is an attempt to bring together our collective knowledge into one place.

Quote
I personally feel obliged only to say what I happen to see in a knot,
without considering if this would have many readers, a few readers, or even none at all.

And yet you voice such angst over this move because
you think it will "bury" [sic sic sick] this thread.

Quote
... the 68 posts in this thread, a number that Dan Lehman tried to ridicule

"ridicule"?!  You have some imagination (in one direction, re me)!
I simply pointed out the extensive damage [sic][sick] you did to
the thread.  YOU, no one else (though you try to blame me!).

Quote
Had I predicted such hatried response,

The only hint of "hate" comes from you, first in the act
of anger and blame.
Now, one can wonder what sort of response/reaction DID you

Quote
Contrary to Dan Lehman's accusations,
there was nothing selfish in my effort whatsoever,
...

Oh, right:  it was the noblest of acts,
deletions done for the betterment of  ... ?

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 23, 2011, 11:17:51 AM
X. not in favour though refusing to cast a vote --since he "knows better ..." [sic]).
Yes, exactly ! You used my own words ! I refused to "vote", because I know better than anybody what a "vote" is : I have gained the right to vote, it was not offered to me. Vote is a sacred thing for a citizen, your opinion poll is for the mass media spectators. It might suit better to you, but not to me, I am afraid...
My opinion was not asked ! And I have not seen the opinion of the person who started the thread, set the tone, and published so many pictures. You have no interest in his opinion either, do you ?

(Derek voted against, but so far hasn't thought to delete his posts to show how much he knows.)

So what ? Am I supposed to be a subordinate to Derek Smith , because I refuse to be a servant of yours highness? Are you trying to gather "votes" again ?
I did not deleted my posts because of the reason you, by the vitriolic twist of my words, are attempting to ridicule again. I deleted my posts because they are not part of any Knot theory, they do belong to the "Practical knots" section - to the structure, form and function of  "Practical Knots" part of it.  And I do not wish to reduce the "Practical Knot" section into a mere "Applications/uses of Practical knots."
I am repeating things that I have already said, but this is what one has to do to defend himself against the advocates, who are repeating their false stories again and again to "gain"=steal any more "votes" from the jury they can !  :)

...as I'm sure you must be running low on them by now

I do not bother, because you are providing new quotes by the dozens ! Good boy ! Keep preaching the way you do, and keep twisting things by those advocate-style "arguments" of yours -which I'm sure you do believe tthat hey are also soooo "clever"!  :)

Quote
[from xarax] I personally feel obliged only to say what I happen to see in a knot, without considering if this would have many readers, a few readers, or even none at all.
And yet you voice such angst over this move because you think it will "bury" [sic sic sick] this thread.

I have not voted for or against anything, I simply do not wish to post anything under a misnomer...But you advocates do not see the difference between a right and wrong word, do you ? You only want to gain "votes" from the jury...Well, keep selling your story. I am not a seller or a buyer, I try to be a creator.

deletions done for the betterment of  ... ?

1) The defence of sacred right to vote when voting is cast between citizens, as an expression of their free will, not spectators, as an opinion poll, a right where advocates have no place ! Advocates exist because of democracy, not the other way around ! And I would not ridicule that right in voting if the bowline is a practical knot or not, or if a rose is a rose or not. You love to reduce that right as much as you can, don t you ? I understand it is a method of gaining the "votes" of humble servants, but not of free men.
2) The defence of my right not to write anything under a misnomer, a false title. ( Advocates do exactly the opposite: they twist the meaning of people s words, and deliberately put wrong labels to texts, just to "gain votes"=steal temporary emotions, and get the "public opinion" of the mass media to their cause.)
3) The defence the right to say things with their proper names, and describe the bowline as a practical knot, and any discussion of the bowline, long or short, , as a discussion about a practical knot, so belonging to the Practical knots section.
4) The defence the right to keep the "Practical Knots"section as it is, till now, and not reduce it to half of its value, by considering it only as an "Applications of Practical knots" section.

Of course, you only have to defend a lesser cause, the "majority"s opinion, don t you ? I had already pointed out to you that you should not leave your day work to become an advocate... :)

Keep twisting my sincere motives, my true words, keep portraying me as a black sheep in the "paradise" you have created, where only a chosen few are permitted to enter..You are giving me  plenty of new lamentable materiel to quote ! . Dan Lehman, have you though where you are going to offer your services, when the "vote" will be 1-0 ? When you would be able only to split your image to a mirror, do you believe the votes will be 2-0,  or 0-0 ?   :)

Good knot tyer, unemployed lawyer, needs a job. Failed twice, but who knows what future has for him ?

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 23, 2011, 12:07:15 PM
To delete your work because you disagree with the move, and at a stroke destroy the meaning in just about everyone else' s work, was, in my opinion, an act of extreme selfishness.

Derek

Thank you for your so kindly evaluating my contribution - of what this contricution was worth of- as you did. However, you are absolutely mistaken for my motives that have pushed / forced me into this desperate act. Do not quote the twisted view of the majority advocate...Imagine that you have spend a month and a half, tying knots, hanging heavy chairs from the ceiling with ropes, taking pictures, learning how to use software programs to transform those pictures into pictures with a white background, as asked...and paying money to buy those software programs, so you are not obliged to use the demo mode, as I had done initially...So, your family is in summer vacancies, while you do wild things, because you love the thing you do, and you love to present it to others, always with the hope that some time in the future, that might serve somewhere...
And then, after 40 days, after 68 posts of yours, suddenly, out of the blue, here come a farce of a democratic procedure, a false "vote" , by a lamentable 5-1 outcome of "votes", to throw this work wherever somebody though it would be less annoying...And imagine that this is not the first time that a "majority" has been orchestrated against you, and turned into some kind of a lynching mob...
What exactly, my dear Derek, would you do ? Of course, being part of the establishment  here, you do not run a similar danger, or you can not imagine a similar situation against you, however good intentions you have.
My real mistake was not the deletion of posts, which was explained by me a number of times...(Read MY quotes, not the "majority "s advocate, and try to understand my true reasons)
My real mistake was the deletion of my back up, which I had kept to offer it to whoever of the participants or not of the Frum asked from me, a silly deletion achieved by the old fox s vitriolic remarks about "selfishness" , that you are now ready to swallow !!
No, my dear Derek, you are wrong here as you were with the Sheet bend/bowline relation,  :), I am probably the more modest and less selfish man you have met  :)...and I am no f... masochist to destroy my own work ! However,  I can not say with certainty that the "majority"s  advocate is not a sadist !  :)  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: admin on August 23, 2011, 12:56:36 PM

This is not a problem. I can re-instate your deleted posts. So I can only echo the Web Admin's question:

Do you agree to the reinstatement of the posts you have deleted?
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 23, 2011, 06:09:00 PM

This is not a problem. I can re-instate your deleted posts. So I can only echo the Web Admin's question: Do you agree to the reinstatement of the posts you have deleted?

OK, I might well have overreacted, and that there was just such a mess, by an unfortunate series of bad luck..We can not control our lives entirely, can we ? And we make smaller or bigger mistakes, when we are being squeezed into a corner, against our will... I would have not deleted my posts, if that deletion were to cause such problems it seems that indeed it did. What the hell, the post you publish is not yours any more, you throw it as a message in a bottle in an unknown ocean, it can float and reach remote islands, or it can sink right in front of your eyes. I do not wish the other participants to feel somehow betrayed by me, in any degree. So, I would be glad to have my posts reinstated, and, please, put them wherever you wish ! ( I also believe that it was the author of the original post, with the main idea and the many fine pictures he had contributed to it, who should have been asked to express his opinion at the first place.)
I have a suggestion ;
(  To people that were disappointed by the unfortunate deletion, I apologize, because, although I was the one who lost more from this story, ( 68 posts, and the work and pictures and texts behind them was not a negligible effort, for my age...),  I should have thought what this action would have meant to them, too. )
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 23, 2011, 06:27:45 PM
You ask me what would I do - I would do what I have done, and that is to ask if the whole thread could be put back exactly as it was
Would you agree to Mel reinstating the whole thing as it was, and where it was, before the move?

I could have not done this. When a vote is cast, however the outcome and the procedure, I feel that I have to respect the fact. ( When your fellow citizens condemn you to drink the poison, you should obey, even if you believe that this vote and its outcome was a farce !  :)) I could only do what I have done, and which I should have not do...because it might be misinterpreted - as indeed it had, also by you - as a "selfish|" (!) action !  :)
Let the Web-administrators do their job the way they think is better, re-instate the posts whereever they believe they should be re-instated, and I will post any criticism in another, proper place - when it will not run the danger to be thought as a means to impose MY way. Advocalligators are dying to twist such cases, especially when they express the will of the "silent majority"!   See you later, alligator !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: WebAdmin on August 23, 2011, 10:46:37 PM
Thank you for your agreement to reinstate the posts, Xarax.

I have never had to do this before, so I will ask Mel to make sure that I know how to do it the right way, so it may be a day or two before they are all back in place.

For the core of the remaining discussion regarding the move of the Bowline thread - there is obviously room for lively discussion on what constitutes knot theory (in my understanding of this I do not have in mind the purely mathematical theory alone, but also esoteric discussions by afficionados of why a group of knots is defined as it is, and how they are distinguished between, and so on).  I will copy this part of my post as the beginning of a new thread to discuss such matters over on Chit-Chat initially, and I will put up a poll over whether or not to keep the Bowline thread on Theory, or move it back to Practical.  I prefer straight yes and no answers on such matters, it's easier for me to find out what people want me to do that way.

Once the final disposition of the Bowline thread is settled, then I can look through to see which of the obtruding posts can be removed.  That will probably be most of the posts of the last couple of days, all of my own posts, and the few which were in sole answer to my question.

Regards

Glenys
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 23, 2011, 11:18:18 PM
Regarding the title "Knot Theory" : I have googled it in the advanced search / this exact wording or phrase:. I have counted the number of times that an article cited there had something to do, however remote it might be, with any "Theory of Practical knots" , as we understand this term here. In the first 100 results, guess what the outcome was : 0 (Zero)
Let the section of "Practical knots" be divided into two sub-sections, the "Applications of Practical Knots", and the "Theory of Practical knots" , or something like this. Or, let there be a label that distinguishes threads/posts along those two broad categories/classifications.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 24, 2011, 06:08:25 AM
Regarding the title "Knot Theory" : I have googled it in the advanced search / this exact wording or phrase:. I have counted the number of times that an article cited there had something to do, however remote it might be, with any "Theory of Practical knots" , as we understand this term here. In the first 100 results, guess what the outcome was : 0 (Zero)
Let the section of "Practical knots" be divided into two sub-sections, the "Applications of Practical Knots", and the "Theory of Practical knots" , or something like this. Or, let there be a label that distinguishes threads/posts along those two broad categories/classifications.

Exactly : there is little or no serious thinking about practical knots
(things in cordage, contrasted with mathematical *knots*).  Which
is why the development of such under this forum is a desirable thing.
Not only is there but shallow thinking --untested assumptions-- about
physical aspects of knots (e.g., the widely opined "bending rope
weakens the outer fibres, which break" (something I have seen enough
of --breaks-- to contradict)), but also scant philosophical investigations
of conceptual & nomenclatural aspects (e.g., What is a *knot*?
(as opposed to an animal, or ...);
... (as a particular *knot* in contrast to any other *knot*);
What are the types/kinds/classes of *knots* (e.g., eyeknot/end-2-end
knot/hitch/stopper/... ; of structure: traced/interlocked/pull-together).

It is just silly to pretend that subdividing the Practical forum to do
this vice using the extant forum is better --or did you find a treasure
validity of a forum title) ?!

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: admin on August 24, 2011, 12:42:06 PM
This is not a problem. I can re-instate your deleted posts. So I can only echo the Web Admin's question: Do you agree to the reinstatement of the posts you have deleted?
I have a suggestion

Sorry but no. You cannot attach strings to this - no matter what knot you use. Your mass deletion of posts severely disrupted this topic and, as a result, was detrimental to the forum community as a whole. I am asking for your agreement out of politeness. I would rather carry out this (extensive) repair work with your support than without it. But either way, the good of this community comes first.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 24, 2011, 06:35:09 PM
This is not a problem. I can re-instate your deleted posts. So I can only echo the Web Admin's question: Do you agree to the reinstatement of the posts you have deleted?
I have a suggestion

Sorry but no. You cannot attach strings to this - no matter what knot you use.

If a suggestion means to "attach string to something"' , you or I need the Google translator roo is proposing !
I suggest you read again my reply, and act accordingly. Sorry, but I am not going to untie your jammed knot.
P.S. If you have the files, the work is not "extensive" at all ! Send them to me, and I will put the replies in order in no time ! If I had copies of those replies, I would have done it by myself. I know what is good for the forum community at least as much as you do, because I am part of it.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: admin on August 24, 2011, 10:38:00 PM
If you have the files, the work is not "extensive" at all ! Send them to me, and I will put the replies in order in no time !

The forum software can handle this itself. I'll get started on re-instating those posts.

Thank you.  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 25, 2011, 03:11:39 AM
If you have the files, the work is not "extensive" at all ! Send them to me, and I will put the replies in order in no time !
The forum software can handle this itself. I'll get started on re-instating those posts.
Thank you.  :)

If so, what was the meaning or purpose of your reply :

Sorry but no. You cannot attach strings to this - no matter what knot you use. Your mass deletion of posts severely disrupted this topic and, as a result, was detrimental to the forum community as a whole. I am asking for your agreement out of politeness. I would rather carry out this (extensive) repair work with your support than without it. But either way, the good of this community comes first.

I guess you used the opportumity to teach me a "lesson" about "the good of the community".
Because I have agreed on this repair already, BEFORE this lesson...(1)
Ok, you wished to show to me some authority...I should not blame you for this, but you should have made it on time !

1) http://igkt.net/sm/index.php?topic=3233.msg20233#msg20233
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 25, 2011, 03:55:20 AM
there is little or no serious thinking about practical knots(things in cordage, contrasted with mathematical *knots*).  Which is why the development of such under this forum is a desirable thing. Not only is there but shallow thinking --untested assumptions-- aboutphysical aspects of knots ... but also scant philosophical investigations of conceptual & nomenclatural aspects (e.g., What is a *knot*? (as opposed to an animal, or ...); ... (as a particular *knot* in contrast to any other *knot*); What are the types/kinds/classes of *knots* (e.g., eyeknot/end-2-end knot/hitch/stopper/... ; of structure: traced/interlocked/pull-together).

I agree with all those descriptions and conclusions...

It is just silly to pretend that subdividing the Practical forum to do this vice using the extant forum is better ...

...but not with this silly sentence, of course ! I do not pretend anything ! I see that people have a difficulty accepting the "theoretical" discussions be mixed within the "Applications/uses of Practical Knots", and I have proposed that a possible solution to this problem is to put labels in front of any thread, indicating the character of the discussion one should expect to find there... OR a split of the "Practical Knots" section into two sub-sections. The one would deal with the applications/uses of practical knots, and the other with the structure/form/funcion/definition of practical knots. The "Knot Theory" joke should have ceased to make us laugh a long time ago !
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 25, 2011, 08:36:00 PM
there is little or no serious thinking about practical knots(things in cordage, contrasted with mathematical *knots*).  Which is why the development of such under this forum is a desirable thing. Not only is there but shallow thinking --untested assumptions-- aboutphysical aspects of knots ... but also scant philosophical investigations of conceptual & nomenclatural aspects (e.g., What is a *knot*? (as opposed to an animal, or ...); ... (as a particular *knot* in contrast to any other *knot*); What are the types/kinds/classes of *knots* (e.g., eyeknot/end-2-end knot/hitch/stopper/... ; of structure: traced/interlocked/pull-together).

I agree with all those descriptions and conclusions...

That would be good, for the conclusion above is
"the development of such under this [viz., knotting theory] forum is a desirable thing".
THIS forum of *knotting theory*.

Quote
It is just silly to pretend that subdividing the Practical forum to do this vice using the extant forum is better ...

...but not with this silly sentence, of course ! I do not pretend anything !
I see that people have a difficulty accepting the "theoretical" discussions be mixed
within the "Applications/uses of Practical Knots", and I have proposed that ...
OR a split of the "Practical Knots" section into two sub-sections [ : ]
The one would deal with the applications/uses of practical knots,
and the other with the structure/form/funcion/definition of practical knots.

But this betrays a disregard for discussing knotting theories so labeled,
unless prefixed with "practical" ?  There should be no problem with
such discussions as anticipated already; there should be no presumption
that *theory* has no bearing on knots seen as practical; but the focus
is on non-*practical* aspects of them (such as nomenclature, such as
classification, such as notions of behavioral mechanics (testable theories,
these).

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 26, 2011, 01:47:07 AM

the conclusion above is
"the development of such under this [viz., knotting theory] forum is a desirable thing".
THIS forum of *knotting theory*.

I do not have an adequate command of the language, but I feel something odd with the term "knotting theory". Of course, it is not wrong, as the term Knot Theory is ! However, "knotting" is a verb, it describes the action/procedure of making a knot, isnt it that so ? I would prefer a term that refers to the studying, examination of the object of this action/procedure, the knot itself. That is why the term "Theory of Practical knots", or "Study of structure, form,function,definition of Practical Knots" sounds better to my ears...Of course, if there is such a thing for Decorative Knots, there should be a similar section for them as well.
I understand that the principal division of the entity "knots", is the division in Practical, Decorative and Mathematical Knots. Then, the priciple division of knots, regarding the kind of our relation to them, is the division in Application/Use, from the one hand, and Study/Theoretical examination (of structure, form, function, definition),  from the other.
Now, what is happening here is that some people want to hijack the Practical Knots forum, reduce it to a mere "Application/Use of Practical Knots" forum, ( that is, divide its value in half...), and have all the knots that do not fall in this highjacked by them category, expelled to the other forum...I will not let them do this trick, as long as I stay in this forum, post the knots I tie in this forum, and I am not baned from this forum... :) I do not buy their hypocritical call for "mis-placed threads", the "voting" farce, and all this smoke screen of their real intentions...

But this betrays a disregard for discussing knotting theories so labeled, unless prefixed with "practical" ?

No. If we should have to do the same for the prefixed as "Decorative" knots, we should have a similar "Study/Theory" section for them, too.

but the focusis on non-*practical* aspects of them (such as nomenclature, such as
classification, such as notions of behavioral mechanics (testable theories,these).

What you label as "practical", I prefer to label as "having to do with Application/Use", in contrast to Study/Theory. I keep the term "Practical", to the distincion Practical-Decorative-Mathematical. So, I translate the sentence above as follows: " the focus is on aspects that do not have to do with applications or uses of them (such as nomenclature, such as classification, such as notions of behavioral mechanics (testable theories, these)"

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on August 26, 2011, 02:18:41 AM
As a personal opinion on the original topic question I offer that the parts of the most common (or first to be named) bowline knot should define any or all the rest that have "hijacked" the bowline name.
Regardless of the nomenclature used to define each and every part, those have to be there to be a Bowline.
It is a fixed loop.

Do the names of the parts change if and when it capsizes?  ???

SS
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 26, 2011, 03:23:13 AM
Do the names of the parts change if and when it capsizes?  ???

I do not think that the capsized parts are the same parts any more,,,so why should they have tha same name ?
I have seen how a double crossed-coils nipping loop capsizes into an "8" shaped one... changing also the path of the tail that goes through it. The two knots do not have any relation any more...If you had not followed closely and very carefully all the steps of the capsize, you would nt be able to figure out if / how the one was transformed into the other ! And the way each of them is nipping the tail that pass through it, is entirely different.So, why should they have the same name ?
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 26, 2011, 04:49:11 AM
... I feel something odd with the term "knotting theory".
...//...
That is why the term "Theory of Practical knots", or
"Study of structure, form,function,definition of Practical Knots"
sounds better to my ears...  Of course, if there is such a thing
for Decorative Knots, there should be a similar section for them as well.

Perhaps we can dispense with "theory" and substitute "philosophy"
or some other term indicating discussions of foundations of things?
--"meta" discussions, might be one way of saying it.

And I don't think that we need to separate such discussions vis-a-vis
*practical*/*decorative* --I don't see 'a priori that there should be
such a gulf between them when the deliberation is on such first
principles & nomenclature; and even if there are different directions,
ideas from one camp might beneficially influence thinkers of the other.

Quote
I understand that the principal division of the entity "knots",
is the division in Practical, Decorative, and Mathematical Knots.

So far as one can tell here, no one is concerned with mathematical
knots --though ideas from those studies might be brought to bear
on some conception of others, such as the defined relations.

Quote
... and Study/Theoretical examination (of structure, form, function, definition),  from the other.
Now, what is happening here is that some people want to hijack the Practical Knots forum,
reduce it to a mere "Application/Use of Practical Knots" forum, ( that is, divide its value in half...),
and have all the knots that do not fall in this highjacked by them category,
expelled to the other forum...

Well, I understand how you might think this, but really
don't agree with your re-ACTion to it, and don't think
that you should even so fear & resist it --and if the adjustment
of another forum title can better reflect our hopes for it,
then all the better.  And as I said previously, *I* think
that the vigor you have put into such "non-practical" (to
some) topics will give improved life to another forum,
and all the usual activity in Practical Knots will continue
to sustain it --which is currently the most active forum.
(Often, in Net fora (?), when one forum accrues great
activity, managers seek ways to split it --if helpful-- so
as to make discussions & research (Search or mere paging
through topic listings) more efficient.  I recall when there
was the Usenet group "rec.bicycles" (pre-WWW days);
it grew tremendously and got split into seven or so
sub-forums (.marketplace, .tech, .rides, . ...).)

And the contentious Move of the long thread should be
seen, without hostility, like planting a mature tree into
a place lacking a forest.  --and, no, not so the tree will die
for lack of light; but so that it will help other trees grow.

Quote
but the focusis on non-*practical* aspects of them (such as nomenclature, such as
classification, such as notions of behavioral mechanics (testable theories,these).

What you label as "practical", I prefer to label as "having to do with Application/Use",
in contrast to Study/Theory. I keep the term "Practical", to the distincion Practical-Decorative-Mathematical.
So, I translate the sentence above as follows:
" the focus is on aspects that do not have to do with applications or uses of them
(such as nomenclature, such as classification, such as notions of behavioral mechanics
(testable theories, these)"

Fair enough; and that the distinction --however called-- does exist
(i.e., we humans can so conceive such a distinction).

Now, how do YOU define "practical knots" ?  --this, you must know,
is an issue with others, with which I have some sympathy, much
ambivalence.  For the presentation of a knotted structure simply
AS "practical" with no indication of why/how so except by it being
posted under the forum of that title, is a not very convincing case
for practicality.
*I* could see such presentations coming --as I earlier said-- in some
(ambitious) exploration (and marking-one's-exploratory *path*) of
the vast knotting universe.  And, yes, I think it is vast --esp. if such
knots as you have found are included.  WHo here has a full grasp
of even Ashley's set of some few hundred (NOT the oft'-quoted
several thousand!) practical knots?  --to which we can easily expand
them from many starting points to a far greater number.

But, back to your conception of "practical knot" :  how do you
understand this?  --for as you've often answered the challenge
by simply waving to the unknown future and claimed that the
knot might be found to be useful!  Isn't it only then, at such
finding (by whomever), that one has the substantiation that the
knot is "practical"?  How do we, without that knowledge, make
the prior determination?  (And if it's only by whim or hope, what
knot is not "practical"?)  (The black-walled corridor beneath the
art gallery above which has a room with a black canvas with a
frame around it and a title (maybe reading "untitlted") : and one
is called "art"!?)

You, after all, have counted my "vast" with expressed doubt at
this; that implies you have some sense of limits on what will
be so called; so, what is it that restrains the discovery of knotted
structures so that it is not vast, so that much of what is found
is deemed "not *practical*" --which your favorite critics might
be surprised to learn you could think!  --or which in any case
they have been more ready to award (that judgement) than you.

--dl*
====

ps:  I am happy that these recent posts have traded substance
and not mere "sound & fury"!  And I'll open a ...
:)   (smiley)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on August 26, 2011, 01:56:04 PM
Perhaps we can dispense with "theory" and substitute "philosophy" or some other term indicating discussions of foundations of things?

I proposed the "Study of...", and I had in mind a title like "Study of structure, of form, of function, of definition" .

And I don't think that we need to separate such discussions vis-a-vis *practical*/*decorative* --I don't see 'a priori that there should be such a gulf between them when the deliberation is on such first principles & nomenclature; and even if there are different directions, ideas from one camp might beneficially influence thinkers of the other.

Practical knots are machines/tools, so they are the subject of scientific/analytical/experimental study. Decorative knots are objects of Art, they are the subject of Aesthetics, they are synthetic, They can NOT be proved or disproved that they are indeed what they claim to be, by a physical experiment
As a person that happened to get involved in both worlds, I know very well the gulf/gap between those "two cultures" C.P Snow was talking about...I am not happy with it, but that is how things are, and WE are not going to change this, I am afraid !   :)

Well, I understand how you might think this, but really don't agree with your re-ACTion to it, and don't think that you should even so fear & resist it -

My reaction might well be proved pointless, even mistaken, ( as it was proved to be in the past). But that does not mean I am going to sit speechless and listen to nonsense, that try to propagate dangerous ideas, ideas I know very well that, if implemented, they are going to reduce the Practical Knots forum to half its value ! I have made much effort ( for my age) to enrich this forum as much as my limited knotting knowledge allowed me to do, so I will not sacrifice this,or the interest some other people showed in my efforts, without a re-ACTion !

Often, in Net fora.., when one forum accrues great activity, managers seek ways to split it --if helpful-- so as to make discussions & research (Search or mere paging through topic listings) more efficient.

Exactly ! I proposed to split the present Practical Knots forum to two, where the one subsection will include everything about the Applications and Uses of Practical knots , and one that will include everything about the Study of structure/form/function/definition of Practical knots. Most, if not all, of the content of the misnamed "Knot Theory" forum will go automatically to the second subsection. WHAT ON EARTH IS WONG WITH THIS SIMPLE SOLUTION, I wonder...But perhaps I know...People that fear and hate the proposed second sub-section, are trying to high jack the term "Practical Knots" for themselves, and throw this sub-section as far away from the first one as they can. Well,they have the right to try this if they have such a narrow view about it, but they will succeed in devaluating the Pacica Lnots section only over my dead/baned body !  :)

And the contentious Move of the long thread should be seen, without hostility, like planting a mature tree into a place lacking a forest. --and, no, not so the tree will die for lack of light; but so that it will help other trees grow.

A nice romantic painting indeed, but you are not as naive to see only this !
The new tree is attempted to be planted UNDER the already grown old tree, so it does not have any chance to grow...And before it will die - as it will, no question about it - it would have destroyed the roots of the old tree as well !
Let the two trees be planted side by side, in the same fertile ground presently covered by the old tree : that is, the fertile ground of Practical Knots forum !

... define "practical knots" ?  --this, you must know, is an issue with others, with which I have some sympathy, much ambivalence.  For the presentation of a knotted structure simply AS "practical" with no indication of why/how so except by it being posted under the forum of that title, is a not very convincing case for practicality.

Tell me Dan Lehman, if you post a knot, like the "Violin" bend, a simple bend, should you indicate why/how this bend is a practical knot, or will be proven to be a practical knot in the future, with the materials used in the future ? Do you have to "state an application" for a bend, for KnotGod s shake ?

And, yes, I think it is vast ...some few hundred... practical knots?  --to which we can easily expand them from many starting points to a far greater number.

I have just finished a first reading of ABoK, and I am left with the impression that it is mainly a book about Decorative knots. Not only because of the number of Decorative knots in comparison to the number of Practical knots that is included, but of the relation of the numbers of the knots that could have been included !
I keep the term "vast" for the number of Decorative knots. I can not even imagine a n upper limit of this vast field, in comparison to the field of practical knots. There, with my limited experience, I do see some boundaries, beyond which knots lose their practicality. I am not saying that the number is not big, I only say that, from which I have sensed from my short journeys into KnotLand, the number is only one order of magnitude greater than the presently known...So , if we have a few hundreds knots, the total number of possible practical knots I reckon that should be a few thousands. But that is ot a vast number, in comparison with the few thousands, or even millions, of the Decorative Knots. And as I have said, with the proper computer tools, we could discover all those knots in a few months, even in a few weeks ! Testing those knots - taking into account all the possible materials, loading conditions, environmental aspects, dressings, etc.- THAT is a really vast area we should explore...in the next 10 generations.... :)

But, back to your conception of "practical knot" :  how do you understand this?  --for as you've often answered the challenge by simply waving to the unknown future and claimed that the
knot might be found to be useful!  Isn't it only then, at such finding (by whomever), that one has the substantiation that the knot is "practical"?  How do we, without that knowledge, make the prior determination?
... you have some sense of limits on what will be so called; so, what is it that restrains the discovery of knotted structures so that it is not vast, so that much of what is found
is deemed "not *practical*"

My two pence : It has nothing to do with a subjectively chosen quality. It has to do with a quantity, and a quantity only. Unfortunately, this quantity is, at present, very difficult, or even impossible, to measure by using well defined notions and procedure. It is the quantity of simplicity.
Simplicity should be taken into account, and an upper limit of it - that has to do with our brain abilities and the economy of material and time while we tie a practical knot - will automatically pose a limit on the number of possible practical knots.
I had the vague idea to split this measure of simplicity of a knot into two separate domains. First, the simplicity of the "base", that is, the initial rope configuration -be it still only a mat or an already tied simple knot - we use to weave our working ends around and through it, to tie the final knot. I suppose we should be, eventually, able, to measure the simplicity of this base- somehow, by the number of rope crossings, for example, or the hand moves this "base" requires to be formed, or by measuring whatever other concrete characteristic of it.
Second the simplicity of the next step, the tucking of the working ends through this "base". I suppose we should be able to measure that simplicity, too - somehow, by the number of tucking, the difficulty of executing the act of a particular tuck, on a particular opening of the "base", by measuring whatever characteristic of the moves required to dress and finish the knot.
Only a simple enough knot can be a Practical knot. And having an upper limit on the number of measured simplicity of each knot, we have a upper limit on the number of possible knots.
Do not take me wrong here. I am not saying that this is the most important thing when we consider which knot is practical and which not ! I only say that this is the thing that can reduce the number of possible Practical knots, from a vastly big one, to a manageable big one ! All the other considerations, taken together, can not generate such a great reduction from a vastly big number to a big number, as the upper limit of simplicity of a knot can. Some knots present an unacceptable slippage, or an unacceptably tend to jam. Considerations about slippage or jamming of a knot can not offer such a great relief in lowering the number of possible Practical knots, as the upper limit of simplicity can offer. Simplicity turns (vast )infinity into a (big, but finite)number!
Now, a simple enough knot might be proved to be a practical knot, or not. However, I think that all the other characteristics are easier to evaluate - that, of course, does not mean that they could be evaluated in a shorter period of time ! Testing all the possible simple enough knots will probably last for one or century, may be more ! And it will require new automatic machines, to execute those testings in an industrial scale !
I know that all those things might sound as "just thin air talk", or blah blah to Practical Knot fundamentalists ! ( Some of them will have to use their Google translator, and some help from somebody else that can think, to understand what I am trying to say...) However, I can only say that this is my two pence opinion, earned the hard way, by tying and untying hundreds of knots ! I have presented about half a dozen new knots, that are practical as much as most of the known knots are practical , and I beg anybody that has a different view, to prove that they are not ! I would be glad if my artificial(compute) and/or DNA inherited(brain) memory will be shortened, and cleared to other interesting things of life !  :)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Sweeney on August 27, 2011, 02:15:30 PM
As a personal opinion on the original topic question I offer that the parts of the most common (or first to be named) bowline knot should define any or all the rest that have "hijacked" the bowline name.
Regardless of the nomenclature used to define each and every part, those have to be there to be a Bowline.
It is a fixed loop.

Do the names of the parts change if and when it capsizes?  ???

I've followed this thread for some time and I think that this quote comes close to what I have been thinking. There is only one bowline (not "a" bowline but "the" bowline) - ABOK #1010 for ease of reference. That said there has built up a bowline family so trying to decide on the characteristics of knots which belong to this family seems to have been the predominant part of this discussion. From that one can look at how far removed from the original any qualified bowline is (by qualified I mean a knot the name of which includes the word bowline or which could include the word bowline if currently it does not or is not named at all). You then have a sort of family tree - to take an example immediately below the bowline are the cowboy bowline, water bowline and the double or round turn bowline. These differ only by one step from the original. Take another step down and you have the end bound double bowline. And so on. Then the eskimo bowline though related fits in another part of the tree perhaps. I hope this concept is clear enough, I am trying to put a visualisation into words. Although a mathematical description of any knot is no doubt possible (and like genetic make up in the plant and animal kingdom can determine perhaps if a knot belongs to a particular family) it needs an above average understanding of the math to follow. Eventually a circle can be drawn around those knots which have sufficient characteristics of the original to be considered related and from that the criteria for inclusion drawn up. Those distant cousins, perhaps recognised as such, are not therefore part of the true family.

If a knot capsizes under extreme conditions into a different knot (as opposed to falling apart) then it should have a different name in my view BUT excluding a formation designed to capsize as in making a carrick bend by reeving the end and then pulling into shape.

Barry
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DDK on August 28, 2011, 04:40:14 PM
The task of classifying, naming or defining can be a difficult one, but, has been done before and in many areas of interest.  I found some interesting comments in the wiki pages on categorization and library classification.  http://en.wikipedia.org/wiki/Categorization (http://en.wikipedia.org/wiki/Categorization)   http://en.wikipedia.org/wiki/Library_classification (http://en.wikipedia.org/wiki/Library_classification)

For example, an alternative to hierarchal ("tree") organization termed "faceted classification" allows for multiple classifications of a set depending on one's focus. http://en.wikipedia.org/wiki/Faceted_classification (http://en.wikipedia.org/wiki/Faceted_classification)

On the wiki for categorization was a section labelled "Miscategorisation" which struck a chord with me.  "Miscategorization can be a logical fallacy in which diverse and dissimilar objects, concepts, entities, etc. are grouped together based upon illogical common denominators, or common denominators that virtually any concept, object or entity have in common. A common way miscategorization occurs is through an over-categorization of concepts, objects or entities, and then miscategorization based upon over-similar variables that virtually all things have in common." (see http://en.wikipedia.org/wiki/Categorization (http://en.wikipedia.org/wiki/Categorization), as of August 28, 2011)

DDK
Title: Concepts and explorations of knotting : What defines a Bowline? - structure, cha
Post by: xarax on September 13, 2011, 02:09:39 PM
The somewhat naive definition of the bowline, based upon the elements of a simpler or a more complex TIB nipping loop and a "proper" collar, has its problems as well. The first one was pointed out since the very beginning of this thread, and has to do with the "crossing knot"-based loops. We can not exclude those loops from the bowline family, without been forced to do the same to the Eskimo bowline - and I believe that this is a unacceptable high price to pay.
Now, the second, more difficult problem has to do with the shape "8" bowline, also presented previously in this thread, under the telling title "to be or not to be a bowline".(1) I think that if there might be a plausible argument in favour of Dan Lehman s view of the bowline - that the collar should not be considered as an independent element, but only in relation to its entanglement / stabilizing function with/on the nipping loop - this shaped "8" bowline-like loop is the best I can think of. What can be said about the nipping loop(s) here ? Is there one nipping loop or two ? The second/higher part of it encircles the RIM of the collar, AND the standing end ! What can be said about the collar ? It encircles the standing end, AND the eye leg of the bight !  In short, a complete mess !  :) Derek, my friend, Ιδού η Ρόδος, ιδού και το πήδημα ( hic Rhodus hic saltus ) !  :)

1) http://igkt.net/sm/index.php?topic=3233.msg20079#msg20079

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on September 15, 2011, 06:40:03 AM
I've followed this thread for some time and I think that this quote comes close to what I have been thinking.
There is only one bowline (not "a" bowline but "the" bowline) - ABOK #1010 for ease of reference.

And what of Ashley's so-called (-disparaged) "left-handed bowline"?
--hardly much of a change from one to the other, here (and there
is the case of the seized (or spliced) tail such that the collar is an eye)!

Quote
If a knot capsizes under extreme conditions into a different knot (as opposed to falling apart) then it should have a different name in my view BUT excluding a formation designed to capsize as in making a carrick bend by reeving the end and then pulling into shape.

But note that this capsizing can be a gradual change of geometry
per force, not necessarily the all-or-none sort employed by the
lattice-tying method for the carrick bend --and who should regard
those drastically different structures as the same *knot* (as we
bump into the undefined "knot" once more)?!

--dl*
====

[ 2011-09-21 edit : 'from on to' => 'from one to']
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: Dan_Lehman on September 15, 2011, 07:03:29 AM
The somewhat naive definition of the bowline, based upon the elements of a simpler or a more complex TIB nipping loop and a "proper" collar, has its problems as well. The first one was pointed out since the very beginning of this thread, and has to do with the "crossing knot"-based loops. We can not dispense with the exclusion of those loops from the bowline family, without been forced to do the same to the Eskimo bowline -- and I believe that this is a unacceptable high price to pay.

[Exclude "exclusion" and it reads correctly; or replace "dispense with" with "admit".]   :)

I say we are bound to face difficulties on account of the
varying geometry of knots per load, per material, per setting;
things are not per-fect!  And we face the issue of what to make
of *knot* --a challenging definition or set of definitions yet to be made.

Now, how should we see the knots presented by photographs here?
We have two stages --set tightly, set loosely & "capsized", or at
least in a different geometry.  (I do not show a regular bowline
here, for surely that is known well enough.)
To those who would insist on seeing both of the eskimo bowlines
as, well, both being *A* (named) *knot*,
do you think the same thing in the case of the (capsized) bowline ?
--for it is arguably a similar change to the commonly seen knot
as is the "Ec" version (to the "E" --in my filename) to the eskimo b. .
(I confess to needing to turn this knot around and scrutinize it
in order to identify it --such a hard turn the tail-side eye-leg makes!)

.:.  So, I see the eskimo bowline as one, like the also cited carrick loop (#1033),
that straddles the boundary I'd like to keep as a *bowline's* essential
quality --a turNip .  And, yet, even this  structure is problematic, as the
helix (it's never a perfect circle (well, nearly never : one could do so w/some
loosely-braided cordage by tucking through the lay, I suppose!)) widens
--when must one call "enough!!"  That is a per-degree differentiating that
eschews some bright line of demarcation.

Quote
Now, the second, more difficult problem has to do with the shape "8" bowline,
also presented previously in this thread, under the telling title "to be or not to be a bowline".
(1) I think that if there might be a plausible argument in favour of Dan Lehman's view of the bowline
--that the collar should not be considered as an independent element, but only in relation
to its entanglement / stabilizing function with/on the nipping loop --this shaped "8" bowline-like loop
is the best I can think of.
What can be said about the nipping loop(s) here ? Is there one nipping loop or two ?

How about zero!  Again, looking to the turNip as the base, where
the eye delivers force into the loop, one doesn't have that here,
with the would-be "loop" more a "turn", not *encircling* the nipped parts
so much.

--dl*
====
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: xarax on September 15, 2011, 10:31:05 AM
... we are bound to face difficulties on account of the varying geometry of knots per load, per material, per setting;

Brrr. You do not like making life simpler, do you ? One is trying to learn swimming into his bathtub, and you throw him into the ocean, to get the whole idea...

do you think the same thing in the case of the (capsized) bowline ?

No, I do not think so. There may be only one (final) stable version of a knot, or more (intermediate) ones, because the geometry seldom varies continuously - but in discrete steps. All those stable versions should be considered as different knots, because the geometry is noticeably different. "Capsizing" may occur due to a lighter or heavier loading, by the tier or the load, it does not matter. The one or more geometrically different stable forms that the knot takes as it is loaded more and more, should be considered as different knots, I believe.

the boundary I'd like to keep as a *bowline's* essential quality --[the]turNip.

This is a road one can take, it is true, to simplify things : Keep the nipping structure as simple as possible, and allow all other things to be more complex. I tried to walk on a different road, allowing the nipping structure to be as complex as desirable, and keep the collar, its formation, as an individual structure, procedure, separated from the nipping loop conceptually - as well as temporally.

How about zero!  Again, looking to the turNip as the base, where the eye delivers force into the loop, one doesn't have that here, with the would-be "loop" more a "turn", not *encircling* the nipped parts so much.

Yes, if you insist in thinking in terms of the simplest possible nipping structure, the "turNip" as you call it, you will probably not be able find any of them here...If you think in terms of complex nipping structures, that can squeeze the working end/tail into their hug from many sides - in the tier s and the load s effort to secure the tail/loop - you would see one twisted - or two consecutive - nipping loop(s), that resembles the shape of an "8"- hence the name given in this contraption.
I do not think that this bowlne-like-or-not fixed end-of-line loop is much related to the Eskimo bowline, although here we have also - a part of - the nipping structure encircling the eye leg of the bight. It was produced by the collapse of the double, crossed coils loop with a Myrtle collar, but, as I have said, that should not be a factor to determine what it is now, in this stable state.
I have not said that "you" would have any problem in defining if this loop is a bowline or not...but "i" do have, and it is a major one...A collar that looks like / is, neither a "proper" collar, or a Myrtle collar, leaves me in a odd in-between no man s land...
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: xarax on September 15, 2011, 01:48:04 PM
the "Ec" version

An Eskimo crossing-knot based bowline, of course. See the attached pictures. Also see (1)
1) http://igkt.net/sm/index.php?topic=3467.msg20145#msg20145

(The first picture of reply#216, with the three capsized bowlines, should have been be made by Photoshop, or by some rare favour of the universe that was never ever offered to me ! I have visited hundreds of harbours, looking for something like this, in vein...
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: Dan_Lehman on September 21, 2011, 06:03:29 PM
the "Ec" version

An Eskimo crossing-knot based bowline, of course.

???  It is that, presumably in the tying, for both of what I present,
but the results --my point, for comparison-- differ in regard to what
central knotting the SPart makes : it is the crossing knot only in
the thick rope, and much a turNip in the 3/8" line.  For me,
that divides the generally started knot between groupings,
with only the latter regarded as "(anti-)bowline".
And the capsized bowlineS ...

Quote
(The first picture of reply#216, with the three [?!] capsized bowlines,
should have been be made by Photoshop, or by some rare favour of the universe that was never ever offered to me !
I have visited hundreds of harbours, looking for something like this, in vain...
...
are put as corresponding different results to that general
tying, where one would prefer to put the results into
different groups.  Btw, I think that there are but TWO
capsized bowlines --not the rightmost one, which has
the tail emerging in the wrong orientation to the tail-side
eye leg; it might be something got by tying a sort of
*granny'd surgeon's bend* and then capsizing that
(i.e., tail wraps SPart and then is tucked out through
the turNip in the opposite direction).   !?

Have you looked at mooring lines of such size?
I see this (in one locale, mainly) so much that I came
to wonder if it was intended --for how could one do this
to such a degree of frequency, otherwise?  But I don't know ... .
(I even salvaged such a knot (like the leftmost orientation)
from the trash, and have it for a souvenir, study item.)
I believe that I also found such a capsized structure in
some thinner line, but for the most part, no; and I have
seen photos of yachting lines under tension with quite
loose collars, uncapsized.

--dl*
====
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: xarax on September 21, 2011, 08:04:08 PM
the results...differ in regard to what central knotting the SPart makes : it is the crossing knot only in the .... and much a turNip in the....

I would be glad if you could elaborate on this a little more. With the help of some "accidentally" taken pictures of knots, in your indoors - or the outdoors - wild, and some plain English I could possibly understand - with the help - or not -  of the Google translator. :) I think that you really believe you have pinpointed some/the(?) crucial difference, but you have not reached a point of understanding that would enable you to express your view with the required clarity and simplicity. It is one thing to "see"  something for yourself, and another thing to be able to define something, so other people will potentially be able to see the same thing...

one would prefer to put the results into different groups.

If we could put the results into different groups - knowing exactly what we are doing, and why we are doing this and not something else - then this would be a proof we already have a definition of the differences, would nt it ? Unfortunately, for the moment, I believe/my humble two pence opinion is we/"I" have not.

Have you looked at mooring lines of such size?

Not really. The mooring lines that are used for recreational sailing boats (up to 60 ft LOA) are much smaller, and the materials used are, most of the times, lightweight contemporary synthetics. Perhaps this makes them prone rather to slippage than to capsizing - meaning that, under heavy loading, they would probably slip before they would have had the chance to capsize. Also, I happen to live near by a sea that has not strong currents or high tides, that would possibly justify the use of heavier lines. ( However, I had not seen something like this in any of the the many harbours - some of them with commercial fishing boats, too - of Normandy, Oslo, Dublin, or Amsterdam I have recently visited... :). I wonder why I am sooo unlucky...)
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: Dan_Lehman on September 22, 2011, 09:04:45 PM
the results...differ in regard to what central knotting the SPart makes :
it is the crossing knot only in the ....
and much a turNip in the....

I would be glad if you could elaborate on this a little more.

Isn't it obvious?
In both of my photo'd cases for the "Eskimo Bowline",
the SPart is *collared*; but in the one case it is so by its
own continuation (this I call the "crossing knot" structure),
in the other (of which I have two photos, from two sides)
it is by the tail's wrapping.  In the latter case, I see the variously
tight helix as reasonably regarded as a turNip and thereby
qualifying *bowline* classification; but in the other case,
I regard the base of the knot as a crossing knot and prefer
to let that different structure build its own grouping.
(They both lie in a grouping of "PET" (post-eye [formation] tiable) eyeknots.)

AND a point to note it that these differences can be ameliorated
by degree via setting & loading, just as for eye knot #1033.
I cannot wait for some sharp boundary --that might not exist.

--dl*
====
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: xarax on September 22, 2011, 11:01:13 PM
Isn't it obvious?

Not to me... Horses for courses. I may be thirsty, I may even be able to smell  the water, but I can not see it...
I see the double, crossed-coils nipping loop and the loops based on it. In this structure, we have also one section of the standing part, the second loop, going around another section of the same part, the first loop. Is it a crossing knot structure ? Of course not. However, if this same structure capsizes, it is turned into a more or less typical crossing knot...
Let us imagine a hypothetical structure, where there is a normal, simple nipping loop, with a closed helical form, AND there is a "continuation" of one section of the  standing part, that makes a "second" turn around another section of the standing part. Is this one-nipping-loop-after-the-other a crossing knot ?  Is the 8 shaped bowline-like loop a crossing-knot-based loop, even if the "first" loop looks more like a tight "turnip" than a lower part of a 8 ?

AND a point to note it that these differences can be ameliorated
I cannot wait for some sharp boundary --that might not exist.

Please, do not tell this to all those people who already suspect / believe that "theoretical" discussions do not lead to any concrete, practical conclusions !   :)
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: Dan_Lehman on September 24, 2011, 07:24:19 AM
Isn't it obvious?
I see the double, crossed-coils nipping loop and the loops based on it. In this structure, we have also one section of the standing part, the second loop, going around another section of the same part, the first loop. Is it a crossing knot structure ? Of course not. However, if this same structure capsizes, it is turned into a more or less typical crossing knot...

I'm lost on what this is (i.e., I don't follow this description).

Quote
...  AND there is a "continuation" of one section of the  standing part,
that makes a "second" turn around another section of the standing part.
Is this one-nipping-loop-after-the-other a crossing knot ?

I don't know, here again, but the turNip is loaded *directly* on
both ends, unlike the *loop* section of the crossing knot --where the
away-from-SPart end turns around the SPart, and then is loaded.
That is my point of distinction/separation/classification (re "bowline").

Quote
AND a point to note it that these differences can be ameliorated
I cannot wait for some sharp boundary --that might not exist.

Quote
Please, do not tell this to all those people who already suspect / believe that "theoretical" discussions do not lead to any concrete, practical conclusions !   :)

Who might these be?
The "leading to ..." wasn't questioned, as I recall; only the
Are we there, yet? aspect.  And I was bent on encouraging someone
to not fear isolation in this "explorative",  theoretical tent --knowing
that it would lead (to various interesting places, even practicality).

--dl*
====
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: xarax on September 24, 2011, 03:51:57 PM
I'm lost on what this is (i.e., I don't follow this description).
...the turNip is loaded *directly* onboth ends, unlike the *loop* section of the crossing knot --where the away-from-SPart end turns around the SPart, and then is loaded.

OK, perhabs it is my mistake.( I find it difficult to verbally describe a knot, in any language...)
Describe those 2 pairs of knots using your words and terms, and tell me if they are crossing-knot bowlines or not, and, if some are but some are not, why is this so.
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: xarax on September 24, 2011, 04:19:10 PM
In this structure, we have also one section of the standing part, the second loop, going around another section of the same part, the first loop. Is it a crossing knot structure ?

I do not believe that anybody can deny the obvious fact that this double "turnip" is a "turnip" ! (See attached picture). However, here also

the SPart is *collared*... by its own continuation (this I call the "crossing knot" structure),
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on September 24, 2011, 05:23:53 PM
The double, crossed-coils based loop - that we probably have to / are obliged to classify within the bowline family of knots, as it resembles the common double bowline so much -  can be capsized/deformed into an 8 shaped loop, that looks more like a crossing-knot based loop. ( See the attached pictures, for the un-collared loops). The transformation here is more continuous than we might had wished: There are many intermediate stages, depending upon the loading and the material used.  So, where exactly the initial bowline is turned into a crossing-knot based loop ? A definition is all about naturally discovered or artificially set - for whatever purpose- boundaries, is nt that so ? If we do not have a boundary, can we have a definition, or only some hands-waving vague description ?
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: Dan_Lehman on September 25, 2011, 05:20:33 AM
In this structure, we have also one section of the standing part, the second loop, going around another section of the same part, the first loop. Is it a crossing knot structure ?

I do not believe that anybody can deny the obvious fact that this double "turnip" is a "turnip" ! (See attached picture).

Hmmm, it's at least something beyond the turNip --as is the
simple double-turn version of the double bowline .

But most clearly it is NOT "However, here also ..."
the SPart is *collared*... by its own continuation (this I call the "crossing knot" structure),
,
but is collared in the usual way, but the tail bight.   :o
--"a proper collar"!  (What are you thinking?)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on September 25, 2011, 12:04:12 PM
First, I would not have said that "the SP is "collared" by its own continuation", even with two pairs of ditto marks...To my mind, collar ( "proper" or not ) and nipping structure do belong to different words, the former to the eye leg of the bight, the second to the eye leg of the standing part. As I have said before in this thread,
... do not confuse [a part of] the nipping loop with a collar : A structure is either a nipping loop or a collar, it can not be both of them, simultaneously !  :)
A collar has its second leg nipped by the nipping loop, and secured because of the action of the nipping loop on it ( which, after its turn around the tree, does not pull as hard as before, so the nipping loop has a much easier job to do...)
The collar is not any U turn of a segment of the rope...The collar is a U turn of the tail, it is a mechanism of the tail, a means of the tail to be secured easier by the nipping loop.
Also, the nipping loop is not any 360 degrees turn of a segment of a rope...The nipping loop is a 360 degrees turn of the standing part around the tail, it is a constricting mechanism that nips the tail, a mechanism to secure the tail.
It is absurd to talk about collars on the standing part, and nipping loops on the working end / tail !

Now, regarding the first pair of two the loops posted at reply#224, the collar(a part of the eye leg of the bight) is U-turned around the standing part, in both loops. What differs is that the ""collar""(a part of the nipping structure, that is a continuation of the (first?) "turnip") is U-turned around the SP, in the first (1a) loop, but around the SP AND the collar( a part of eye leg of the bight), in the second (1b) loop. So, the collar of the tail of the loop makes a U-turn around one strand of the SP, in the first loop, but around two strands of the SP, in the second loop. As the two collars, the collar at the eye leg of the bight, and the ""collar"" at the continuation of the (first?) "turnip" are interwoven together in the second loop, that loop should be more secure than the first. Whether this second (1b) loop should still be considered a crossing-knot based bowline-like loop or nor, it is not obvious to me...
We have a  similar, but even more complex, situation at the other pair of loops shown in reply#224. The second (2b) loop should perhaps be considered as a crossing-knot based loop, ( the continuation of the eye leg of the bight and the continuation of the standing end cross each other, dont thy ?), while the first (2a) loop looks more as a double interwoven-collars bowline. However, they are essentially the same knot, the Constrictor bowline, in its two variations.
The situation is more clear in the case of the double, crossed-coils bowline shown at reply#225. We have a "proper" collar, indeed, and a double coils nipping loop - so, according to my definition, it IS a bowline... -, but the SP makes also a  U turn around itself - so, according to your definition, it is a crossing knot based loop...The similarity of this loop with the double bowline ( double-turn bowline) makes things worse for you, not for me !  Are you going to deny the inclusion of the double bowline into the bowline family, as you did for the Eskimo bowline -  while you accept the ABoK#1033 ? Whoa !   :) THAT is a position really difficult to defend !
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: Dan_Lehman on September 27, 2011, 06:40:30 AM
Describe those 2 pairs of knots using your words and terms,
and tell me if they are crossing-knot bowlines or not,
and, if some are but some are not, why is this so.

The first two I group as crossing=knot-based eye knots,
NOT bowlines --and though the tail makes a "proper collar",
the SPart nevertheless effects a collaring of itself in its turn
around itself, which distinguishes it from a turNip.

The latter two are not bowlines by my (current (!)) thinking,
either, as there again is no turNip feeding an eye leg
--rather, from the initial turn of the SPart the rope flows
back into further construction of the nub.
But here I can sense my position is on (at best?) diminishing
ground; you will want to thrust the oft'-cited "water bowline"
at me --its more-recently presented clove base being cousin
to these knots' constrictor bases.  I'm left defending my
position by pointing to *impurities* in the continuation of
the SPart from a turNip into <whatever> --where pure
continuation by reiteration of the turn is presumed acceptable,
but this deviation into the clove not.
(I have thought such structures should be considered
"false" --or some better term of amelioration-- "bowlines"
at best.)

--dl*
====
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: xarax on September 27, 2011, 01:55:44 PM
the SPart ... effects a collaring of itself in its turn around itself, which distinguishes it from a turNip.

You do not need to use the term "collar" - as a noun, adjective or verb- to describe the U-turn of a "continuation" of the SP around itself, I believe. It blurs rather than clarifies your position.

from the initial turn of the SPart, the rope flows back into further construction of the nub.

I see any turn, the "initial" or the following one(s), as part of the same nipping structure -  if it is located in the same place, of course : we can have more than one nipping structures, the one after the other. So, this "further construction"  can be just a part of the first nipping structure, or part of a second nipping structure.

...pure continuation by reiteration of the turn is presumed acceptable

If that is so, the double (coils) bowline, (in the common, parallel, not-crossed coils form), should also be considered as a bowline. You have achieved a slight generalization - the FIST one, to my view... :) - by this clever use of the term "reiteration".

If you want to remain so restrictive with what you accept as a "proper" bowline nipping structure,  with this image of the so-called "turnip" you have in your mind, I do not understand why you insist that the ABoK#1033 is a bowline...The images back at reply #49 (!), show that - at least in its capsized form - it is a crossing-knot based loop and not  a bowline, according to your  criteria. ( To me, it is not a bowline, not because it does not have a "proper" nipping structure - a "turnip", as you call it - but because it does not have a "proper" collar.)

Now, there are some new candidates for this so desirable member-of-the- "royal"-bowline-family status - which is expected to remain desirable, if the blood that flows into the veins of a member should be as "pure" and  blue as the "turnip".  :) See the discussion at
http://igkt.net/sm/index.php?topic=19.msg20883#msg20883
and my opinion at
http://igkt.net/sm/index.php?topic=19.msg20890#msg20890
It is  amusing that, although I feel the need to generalize the notion of the common s bowline s nipping loop - so it would include any TIB nipping structure tied on the standing part -, I am not ready to accept a similar, (and perhaps simpler) generalization for the common bowline s collar !  :) For me, a "locked" bowline- by any tight, secure hitch tied around the standing part, in place of the simple "proper" collar -  is not a bowline any more !   :) It might well be considered as a compound knot, but I believe that the spirit of the bowline has departed / is absent in such fixed end-of-line loops, however secure they might have become by the inclusion of such a "lock".

Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: Dan_Lehman on September 27, 2011, 05:22:56 PM
the SPart ... effects a collaring of itself in its turn around itself, which distinguishes it from a turNip.

You do not need to use the term "collar" - as a noun, adjective or verb- to describe the U-turn of a "continuation" of the SP around itself, I believe. It blurs rather than clarifies your position.

?!  Rather, I think that you have an overly restrictive sense
of "collar", such that my use rubs it sore.  But what I point
to --by any name-- is that the pure circle of tightening that
is evident, quintessential in the turNip is broken by the Spart's
into the SPart and not purely constrict the nip (given friction).

Quote
from the initial turn of the SPart, the rope flows back into further construction of the nub.

I see any turn, the "initial" or the following one(s), as part of the same nipping structure -  if it is located in the same place, of course : we can have more than one nipping structures, ...
...
but we needn't regard them as "bowlines" --that is the question.

Quote
...pure continuation by reiteration of the turn is presumed acceptable

If that is so, the double (coils) bowline, (in the common, parallel, not-crossed coils form), should also be considered as a bowline. You have achieved a slight generalization - the FIST one, to my view... :) - by this clever use of the term "reiteration".

Whether this is a generalization of the structure, or, perhaps,
just a *2nd*, agreed acceptable structure to include, is debatable.
Framing it in this latter way ("2nd") is intended to deny "slippery slope"
charges, though it is a bit awkward.

Quote
I do not understand why you insist that the ABoK#1033 is a bowline...The images back at reply #49 (!), show that - at least in its capsized form - it is a crossing-knot based loop and not  a bowline, according to your  criteria.

my words, not every 30th one!" : for I expressly stated
that this knot has a range of orientations, some of which
qualify --rather obviously-- to being an eye knot based on
a turNip --which can be drawn up to otherwise be
a crossing=knot-based eye knot, like the Eskimo bowline.

Quote
It is  amusing that, although I feel the need to generalize the notion of the common's bowline's nipping loop - so it would include any TIB nipping structure tied on the standing part -, I am not ready to accept a similar (and perhaps simpler), generalization for the common bowline s collar !  :) For me, a "locked" bowline- by any tight, secure hitch tied around the standing part, in place of the simple "proper" collar -  is not a bowline any more !   :) It might well be considered as a compound knot, but I believe that the spirit of the bowline has departed / is absent in such fixed end-of-line loops, however secure they might have become by the inclusion of such a "lock".

Yes, that is peculiar.  I look to the SPart's treatment of the
knotted material as the essence, here, at least; how that
turNip's effect is secured then becomes the varying factor
that enumerates the group.

--dl*
====
Title: Re: Concepts and explorations of knotting : What defines a Bowline? - structure,
Post by: xarax on September 27, 2011, 06:06:39 PM
you have an overly restrictive sense of "collar", such that my use rubs it sore.

True. I wonder why...I suppose that, using the bowline, at some point I have decided - consciously ot not- to denote as "nipping loop" the essential part of the knotting operation at the first leg/stage of tying a bowline, and as "collar" the essential part at the second leg/stage. Two different names, for two structures that are tied in two different legs/stages...a seductive economy of notions.

the loading from the tail-end will press into the SPart and not purely constrict the nip (given friction).

Evidently, but so what ? It will constrict the nipping loop nevertheless, so it will reinforce the initial gripping action of the nipping structure on the tail, too - that was the original purpose of the nipping loop in the first place. The fact that some of the internal tensile force will be "wasted" in this "pressing" of the standing part on itself, indeed, does not mean that any additional structure - besides the initial closed helical structure you call "turnip"-, by amy continuation of the standing part, will be condemned to be useless ! I have performed some home-made tests with the Constrictor and the Pretzel bowlines, and I have seen that the additional structure is noticably effective. Of course, we need detailed laboratory tests to be sure about it, and quantify the results.

I expressly stated that this knot has a range of orientations, some of which qualify --rather obviously-- to being an eye knot based on
a turNip

OK, I stand corrected. I have missed or I forgot that statement. ( Within/after 230 posts... :))
Title: Is this thing a bowline ? If not, what is it ?
Post by: xarax on January 08, 2012, 10:14:41 AM
According to my definition, this loop should be described as a bowline-like loop.... It has a "proper" bowline collar, not more complex than many Janus-like secure bowlines we have, Moreover, it has a nipping structure on the standing part before the tip of the loop, and, although this nipping structure is nothing more than a wide open helical nipping "loop" (?), nobody can deny that it nips the tail nevertheless - and it nips it in a most effective  way ! Indeed, as the interested reader would discover the moment he ties this loop, the grip of this combination of the simple nipping structure- complex Constrictor based collar, is so tense, that we can not possibly talk about having an "adjustable loop" here ! A noose, that is not, for sure. Moreover, although we can adjust this loop if we wish, when it is loaded it looks more as a completely fixed loop - so tight is the connection between the open helical nipping structure and the Constrictor collar.
I am not happy that this loop falls into my definition of the bowline...but what can I do ? I see no escape route here...However, for the time being I call this loop "Adjustable Constrictor loop", because I see some knot tiers around that are already weary a little bit ... :) If I take the liberty to call this thing a bowline, I am afraid they will be much-much more !

http://igkt.net/sm/index.php?topic=3020.msg21688#msg21688

Title: Re: Is this thing a bowline ? If not, what is it ?
Post by: Dan_Lehman on January 08, 2012, 07:01:43 PM
According to my definition, this loop should be described as a bowline-like loop....
... I am not happy that this loop falls into my definition of the bowline...but what can I do ?

Find a better definition!

Quote
However, for the time being I call this loop "Adjustable Constrictor loop",
because I see some knot tiers around that are already weary a little bit ... :)
If I take the liberty to call this thing a bowline, I am afraid they will be much-much more !

This knot too directly is based upon a helix rather than a loop
--acknowledging that the distinction between them comes in
some arbitrary measure (as we have no perfect circle/loop).
(It's an old acquaintance from my seeking to create a

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on January 08, 2012, 07:34:55 PM
Find a better definition !

Well. I try, but i do not see much progress, after 234 posts...Perhaps one should reach 1234 ?

This knot too directly is based upon a helix rather than a loop
--acknowledging that the distinction between them comes in some arbitrary measure

Correct, but make just another step, and tie it with another, second helical coil...and then another, and another...At some point, those coils will touch each other, and then we will suddenly have many loops ! When exactly do those helical coils cease to be helices, become loops ?   :)
( I have tied it with a two-coils helix, and I can not say that it was safer than the one-coil version, because the one-coil version seems to me to be as safe as it could possibly be ! Perhaps one should test it with a slippery spectra/dyneema rope...)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on January 11, 2012, 08:09:48 AM
This knot too directly is based upon a helix rather than a loop
--acknowledging that the distinction between them comes in some arbitrary measure

Correct, but make just another step, and tie it with another, second helical coil...and then another, and another...At some point, those coils will touch each other, and then we will suddenly have many loops ! When exactly do those helical coils cease to be helices, become loops ?   :)

It is not number except in that you have constrained
the space for them; the crux is that there is no boundary
line of geometry --except as we might define, by some
arbitrary imposition, for the sake of definition(?)-- to make
the distinction.  --reminds me of your insistence on seeing
"shear" in some cases and not others; the zeppelin can
e.g. be left loose on setting and then tensioning will see the
SParts' turns be that of bowline's and the nipped tails
much less disposed to visions of *shear* and compression
vs. nipping and tension.

I think we'll just have to accept that there is no boundary,
but that there ARE fairly distinct (end) cases between which
come a sequence of compromises & ameliorations of one
towards the other extreme.  (In trying to ensure good security
--under tension(!)-- for my seeking the "gradual curvature
in the SPart" playing with a helix, the later (farther along
into the knot from the SPart feed) turns would be more
nearly close & "loop" like, for this secure binding, so to
enable the SPart's initial passage to be more nearly
uncurved and presumed-to-be strong, friction building
upon the material gradually.  (Likely a pipe dream of real
effect in some actual usage, maybe only "strong" to the
test device, and maybe that only on slow-pull tensioning.)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on January 11, 2012, 01:34:38 PM
the crux is that there is no boundary line of geometry --except as we might define, by some arbitrary imposition, for the sake of definition(?)
I think we'll just have to accept that there is no boundary,but that there ARE fairly distinct (end) cases between which come a sequence of compromises & ameliorations of onetowards the other extreme.

It would be great if there were, would nt it ? I do not feel comfortable wth loose knots or definitions of knots...

friction building upon the material gradually.

I say something perhaps similar, when I insist that, if the working end/tail is nipped in more than one points into the knot s nub, it is better if it is nipped harder in the last points - the last line of defence against slippage - than at the first ones.This way the knot does not run the danger to slack, and some of the anti-slippage action on the last points be left unused.

P. S.
reminds me of your insistence on seeing"shear" in some cases and not others

Reminds me of your insistence to put into people s mouth words never pronounced by them ! I had never said this, because that would be wrong : Shear forces exist everywhere, except in a straight tensioned line ! I said that the role of the shear forces was the primary role, in the complex function of knot s nub to secure the tail. If you have not got the difference between Zeppelin bend and the other interlinked overhands bends by now, I guess you will not get it ever... :) The fact that the Zeppelin s tails can work/be secured even with loose bights, is a proof you can not see, and the fact that any additional tension accumulates compression forces as well, can not cancel the reality of the first fact !  I rest my case !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on January 19, 2012, 07:56:03 PM
there are some quite simple bowline extensions that do well to add security, maybe even a bump of strength--putting a 3rd or 4th diameter in the central nipping loop--, so that rope users can meet their needs with that knot.

In relation to security, the most essential part of those bowline extensions is not the 3rd or the 4th diameter going through the central nipping loop, but the second collar around one of the three limbs of the initial knot. The positive contribution of the second collar is certain, while that of the 3rd ( and, to a greater degree, of the fourth) diameter is debatable, and has yet to be demonstrated. The nipping loop takes a more round, apparently more efficient nipping shape, that is true, but the nipping force on each rope diameter is reduced by 1/3... And we can be sure that the nipping action on each individual rope strand of a bundle of many strands will get less efficient after a certain number... but we do not know what this number is. I will not surprised if it turns out that 4 strands going through a nipping loop are in fact nipped not much more, or even less efficiently than 3... and I would love to be sure that 3 is better than 2, as I am sure that 2 collars are better than one.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on January 20, 2012, 06:25:24 PM
In relation to security, the most essential part of those bowline extensions is not the 3rd or the 4th diameter going through the central nipping loop, but the second collar around one of the three limbs of the initial knot.

We should remember that in the most modern materials
of HMPE (Spectra / Dyneema) and, I think, Vectran and
aramids (Kevlar / Technora / Twaron), there is inadequate
security when tensioned/loaded of the bowline (and have
seen the double bowline let rope just flow out through its
"doubled" nipping turns!!).  One needs to do something with
the SPart in order to preclude such insecurity/slippage (and
the clove-hitch("water") bowline is one solution to that).

But the important security when slack, loosening vulnerability
of the bowline --which is critical for kernmantle-rope users
(and, I should think, some applications with springy polypropylene
cordage, e.g.)--, might be redressed by the extensions that take
the tail through the knot further.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on June 26, 2012, 08:48:02 AM
At risk of doing the wrong thing..I've revived this topic.

I read the warning notice re no posts in this topic for 120 days.... I did consider starting a new thread but, it seemed logical to continue.

Anyhow, this is to advise that I have updated my paper on Bowlines.

Click on knots and knotting concepts from the list. Its a PDF file - so you need Adobe Acrobat reader to open and view the file.

All articles and papers on the site have been made free to the public.

I would welcome any considered and constructive feedback on my theoretical proposition regarding Bowlines.

I must advise that I am bound to acknowledge the hypothesis of Derek Smith - as my work draws heavily on this.

Mark
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on June 26, 2012, 11:48:19 AM
I would nt describe the following comment as "exciting"  :)....  I am not even sure that it makes any sense, in relation to the security of a bowline.
What happens in a bowline if, intentionally or by accident, one of its two essential elements, the collar, cease to exist altogether ? Will this half-bowline still be capable to hold some loading ? This is a somewhat far-fetched measure of the security of the bowline, but I think that is not completely irrelevant. The thought that a knot would still function adequately well - at least for some brief moments. and when loaded with a small only percentage of its maximum capacity - even if/after it is severely de-structured, brings piece to mind...
One secondary, yet essential function of the collar, is to keep the nipping loop retain its closed loop shape - and prevent it to run the danger and degenerate into an open helix and, subsequently, unwind completely. Some double bowlines ( with two collars, the one after the other ), use this assistance from their collars less than other secure bowlines. So, their nipping loops will remain closed, and they will continue to nip the tail hard and prevent it from slipping out, even without the help of the collar (at least to some degree, for some brief time and for some light loading ). We may conjecture that these bowline will be more effective that the others in their complete form too - just as they were in their half-untied form.
The most well known examples are the Water bowline and the Girth-hitched bowline. Without their collar, they look like the configuration used by Captain Mullins (ABoK#160 ), or a "Hitch series" (1)- so they do hold adequatelly well. Even without detailed experimental testings, we may suppose that, with their collar on, AND with a second collar and the tail going through both nipping loops for a third time ( three rope diameters nipping loops), their security will be enhanced as much as possible, yet they will remain easy-to-remember-how-to-tie and easy-to-untie end-of-line loops. ( " Mirrored bowline" ).

1)   http://storrick.cnc.net/VerticalDevicesPage/Ascender/KnotPages/KnotHitchSeries.html
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on June 26, 2012, 09:11:05 PM
I would nt describe the following comment as "exciting"  :)....  I am not even sure that it makes any sense, in relation to the security of a bowline.
What happens in a bowline if, intentionally or by accident, one of its two essential elements, the collar, cease to exist altogether ? Will this half-bowline still be capable to hold some loading ? This is a somewhat far-fetched measure of the security of the bowline, but I think that is not completely irrelevant. The thought that a knot would still function adequately well - at least for some brief moments. and when loaded with a small only percentage of its maximum capacity - even if/after it is severely de-structured, brings piece to mind...

Such as the fabled sheepshank, which sports a "collar"
only as seemingly peripheral decoration, yet could hold
such important loads as might be drawn from a ship?!

Quote
One secondary, yet essential function of the collar, is to keep the nipping loop retain its closed loop shape - and prevent it to run the danger and degenerate into an open helix and, subsequently, unwind completely.

Indeed, and I maintain that there isn't anything "secondary"
to this, but that IT is the quintessential aspect of a "bowline"!
To the point that I find the following item in the paper's definition
to put the cart before the horse:
Quote
3. That all Bowlines fundamentally consist of a bight component that is held and stabilised by an encircling nipping turn component.
No, rather, the relationship is the other way 'round :
bight stabilizes (serves) the nipping loop (master).
Further, I don't insist on a bight component at all, and thus
accept the so-called "Myrtle" eyeknot as a *bowline* .

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on June 27, 2012, 04:10:26 AM
One secondary, yet essential function of the collar, is to keep the nipping loop retain its closed loop shape

Indeed, and I maintain that there isn't anything "secondary" to this

" Secondary" function, only in comparison to the primary function of the collar : to help the nipping loop prevent the slippage of the tail - because that is what any end-of-line loop ( indeed, any knot ) is supposed to do ! To firmly attach the tail on the standing part. How does the collar achieves this ? By just being a collar, i.e. a U turn around a stable element, such as the standing end - in the case of the common bowline - or the eye-leg-of-the-standing-part - in the case of the "Eskimo" bowline. ( The U turn of the Sheepshank is not a collar, it is a bight in mid air...) What an ingenious invention of the human species was this U turn ! However, as said, the primary element of the bowline is the nipping loop, and this is clearly revealed in the cases of the collar-less " half-bowlines' , the ABoK#160, the " Hitch series" and , of course - how did I forget to mention it ? - the Sheepshank.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on June 27, 2012, 05:24:28 AM
Adding some photos to illustrate key theoretical concepts:

Quote

Sr. Member
*****
Posts: 1951

Re: Myrtle Hitch not in ABOK?
? Reply #12 on: October 17, 2009, 05:41:06 AM ?
Quote from: Andy Asan on October 16, 2009, 06:21:56 PM

Dan, which one is the Myrtle, and which one is the Anti-Bowline?

The left one, if properly oriented/dressed, is an anti-bowline (my term);
you show it in odd (dis)array, instead of with the *bowline*-characterizing
(and here "bowline" in inclusive of "anti-") nipping loop of the S.Part.  The
right one is easier to see, it being in better form.

The sheepshank has elements of a bowline but, it is not a bowline on account of no fixed connective eye loop.

The photo of the 'Myrtle'? is poor (from a previous post in this forum) - I will re-photograph it in high resolution.

The Carrick loop ("ABoK #1033") also has elements of a bowline but is not a bowline on account of the nipping turn not encircling the bight component and applying equal tension on both legs of the bight. However, it does have a fixed connective eye loop.

The Eskimo bowline fulfills the criteria to be awarded the title of 'Bowline'. It has a bight component that is encircled, gripped and stabilized by the nipping turn component.

I note Dan Lehman's point re the servant and master - that is, the bight serves to stabilize the nipping turn. It is true that if the bight is removed from the nipping turn - the nipping turn no longer encircles and grips anything. I still take Derek Smith's view that you need both components to form a bowline.

Note: (added)... the images of the 'Myrtle' and sheepshank are not meant to imply qualification for the title of 'Bowline'. I am simply presenting the images to show the (possible) presence of a 'bight' component and a 'nipping turn' component.
...

(http://)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on June 27, 2012, 07:13:38 AM
Adding some photos to illustrate key theoretical concepts:

Quote
Dan, which one is the Myrtle, and which one is the Anti-Bowline?

The left one, if properly oriented/dressed, is an anti-bowline (my term);
you show it in odd (dis)array, instead of with the *bowline*-characterizing
(and here "bowline" in inclusive of "anti-") nipping loop of the S.Part.  The
right one is easier to see, it being in better form.

The image given for "Myrtle Anti-Bowline" is grossly misleading
as to the nature of the knot --more resembles (in its open form)
a crabber's eye knot in implying a mere "U" in the SPart
vice a nipping loop (which tends towards a helix).  AND it wrongly
fuses the names of distinct knots.  (The tail for Myrtle enters the
nipping loop as does that for the common bowline and then differs
by making just a loop-wrap/turn vs. bight/collar ; whereas the
entry is from the opposite side for an "anti- [hence this prefix!]
bowline".

Swapping which *side* of the tail-wrap gets loaded, as I've indicated
in my quote, nicely swaps between the two knots, as the one works
well with the tail finishing towards the eye, the other (Myrtle) away
(re stability, nip).

> The sheepshank has elements of a bowline but,
> it is not a bowline on account of no fixed connective eye loop.

Well, duh, yes; which brings an unmade criticism : that THIS
aspect is most fundamental ( = "#1") of the definition (and
could well be overlooked in presumption).

Quote
The Carrick loop ("ABoK #1033") also has elements of a bowline
but is not a bowline on account of the nipping turn not encircling the bight component
and applying equal tension on both legs of the bight. However, it does have a fixed connective eye loop.

Well, you'll not sell this perspective to me.  It fits my definition
of "bowline" fine, if not hauled to the point that the "nipping
loop" becomes a crossing knot base.

Quote
The Eskimo bowline fulfills the criteria to be awarded the title of 'Bowline'. It has a bight component that is encircled, gripped and stabilized by the nipping turn component.

Here, too, there are disturbing variances for those who care to look
and explore differences in setting --loose can see "loop"=>"helix"
(well, it's always that, but more so); tight ... crossing knot base.

Quote
I note Dan Lehman's point re the servant and master - that is, the bight serves to stabilize the nipping turn. It is true that if the bight is removed from the nipping turn - the nipping turn no longer encircles and grips anything. I still take Derek Smith's view that you need both components to form a bowline.

But what I said wasn't removing the bight entirely, but just removing
it from "collaring" the SPart --which goes also against X1's remark :
Quote
the primary function of the collar : to help the nipping loop prevent the slippage of the tail
... By just being a collar, i.e. a U turn around a stable element
--
is that a sheepshank shows that this "U"/bight could-be "collar"
can be deprived of the asserted stabilizing (or U-turn-around...) functions
and a knot still works, from the behavior of the nipping loop alone.

Now, I see that I, too, once had stronger feelings for the "collar" bight,
and thought about naming *my* "Lehman8" "bowlinEight" on
account of a more easy-to-pry loose collar of the fig.8 base than
is normally the case (it being now a single strand, of the base component,
and not also a "rewoven" twin).  But then I thought otherwise, and am
not compelled in recollection to relent : no, the strong characteristic
of *bowline* to me is the nipping loop --at least I see that as a good
binding aspect for some named genus/family/order of knots, which
at the moment I'm feeling fits "bowline" (and "anti-bowline", with

--dl*
====

ps:  I quite agree that continuing the dormant thread was the right thing
to do, vs. starting a new one only to have to refer to all this one's ideas.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on June 27, 2012, 11:01:28 AM
Hi Mark,

As you were the creator of this thread, I would hope other members would be happy enough to have you develop it further.

Well done on your 'Analysis of Bowlines' document.  It is a nice piece of work.  I would make one comment which is hopefully constructive - you publish a strength test on the EBSB, declaring it to be ca 73% to 77% which implies that the knot is a significant improvement over the basic bowline.  But then one notes that the calculation is performed against the declared minimum rope strength - not the actual rope strength, so these results will have been overstated by some amount by which the tested rope actually exceeded the declared minimum value.  You would have made this test a little more valuable if you had included a test on the basic bowline under the same test conditions so a genuine comparison could have been made if indeed the EBSB is stronger than the basic.

It has made interesting reading going back over this topic again.  I learned a lot from other posters, but I am afraid that I still cannot countenance the concept of a Myrtle bowline or a Sheepshank bowline, so to preserve my sanity I will abstain from further discussion on the subject.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on June 27, 2012, 01:28:13 PM
Let me try to re-phrase some things, in order to better express what I believe about the matter.

The sheepshank has elements of a bowline, but it is not a bowline on account of no fixed connective eye loop.

The sheepshank has elements of a bowline, but it is not a bowline on account of no collar .

The Carrick loop ("ABoK #1033") also has elements of a bowline, but is not a bowline on account of the nipping turn not encircling the bight component and applying equal tension on both legs of the bight.

The Carrick loop ("ABoK #1033") also has elements of a bowline, but is not a bowline on account of the collar not being like the common bowline s "proper" collar.

[the collar and the nipping loop =] the servant and master - that is, the bight serves to stabilize the nipping turn.

Thy collar is not just "a bight" , it is a loaded bight, a U turn of the working end around a stable element. So,

This loaded bight = collar serves to :
1. Help the nipping loop keep the tail from slipping through it.
2. Keep the nipping loop retain its closed loop form, and do not degenerate into an open helix.

( I think that the #1 function is more important /primary than the #2, but this is not such an important thing anyway. It may be only a matter of semantics.)

It is true that if the bight is removed from the nipping turn - the nipping turn no longer encircles and grips anything.

An obvios missunderstanding looms here.

The (loaded) bight that we call collar can well be removed from the nipping loop, as a loaded bight - the nipping loop will continue to encircle the eye-leg-of-the-bight, i.e, only the one strand, that which was one of the two legs of the collar before that removal. When I say that we may remove the collar, and be left with a half-bowline, I mean remove the second leg of the collar, the "proper" tail.

Both the ABoK#160 and the Sheepshank are " half-bowlines"  in the sense that they have no collar - but, of course, there is something left, that the nipping loop encircles and grips !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on June 27, 2012, 01:58:58 PM
the point that the "nipping loop" becomes a crossing knot base.

The problem is that this "point" is, in fact, a grey area.

If we would allow ourselves to go beyond the common nipping loop, and consider instead any nipping structure ( that is topologically equivalent to the unknot and can be untied at exactly the same time the tail is removed  from its passage through it,  in other words, a " nipping structure + collar" compound knot that can be untied in one step) - then we can achieve a more general definition of the bowline. Of course, doing this, we run on the reverse problem ; how do we can now rrestrict that definition, so it does not include too many end-of-line loops that do not resemble the common bowline at all.

...which goes also against X1's remark :
Quote
the primary function of the collar : to help the nipping loop prevent the slippage of the tail
... By just being a collar, i.e. a U turn around a stable element

I have explained what I mean in the previous post.
I wouldn't describe as nipping loop a bight that encircles nothing but thin air , of course, - as I do not describe as collar a bight that encircles thin air ( The Sheepshank s bight(s)).\
When I say " we can remove the collar" from a bowline, and leave a half-bowline that has only a nipping loop in the place where the bowline was before this removal , I mean ( and, indeed, I could not have meant anything else, could I ?) to remove the one leg of the collar, the "proper" tail - so the loaded U turn around the standing part or the eye-leg-of-the-bight is not loaded, not U turn around something any more !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on June 27, 2012, 02:14:01 PM
Hi Mark,
a Sheepshank bowline
so to preserve my sanity I will abstain from further discussion on the subject.

:)

( I had said " ABoK#160" "half-bowline",  and Sheepshank "half-bowline",  in purpose !
Please, reconsider your abstain - I am convinced that knots bring us close to insanity, indeed... but, at the same time, they keep us from falling into it - iff they are tied and dressed properly !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on June 28, 2012, 02:39:49 AM
Quote
What happens in a bowline if, intentionally or by accident, one of its two essential elements, the collar, cease to exist altogether ? Will this half-bowline still be capable to hold some loading ? This is a somewhat far-fetched measure of the security of the bowline, but I think that is not completely irrelevant. The thought that a knot would still function adequately well - at least for some brief moments. and when loaded with a small only percentage of its maximum capacity - even if/after it is severely de-structured, brings piece to mind...

An interesting proposition.

I did take a sequence of photos at various milestone loadings of a Bowline ("ABoK #1010") - up to 10kN force then stopped.

Although I am dissatisfied with the photos - because I should have taken them from the 'front' (ie the front as defined by Dan Lehman - which properly shows the operation of the nipping turn) - I also could have woven those darn little tracer threads into the knot structure as per Dan Lehman. However, the act of sewing and the fine motor skills and effort required to weave those tiny threads are a PITA! (I honestly believe that Dan invented the idea of the cotton threads purely to cast his cruel sense of humor on poor unsuspecting fools such as myself who are willing to do his bidding).

My next effort at photography will show the Bowline from the 'front' - and I hate to say it, I'll weave those cotton threads (I will chant a curse to Dan while threading my needle) - and hopefully finally come up with some useful photographic data.

But, of greater interest is the idea from X1 (alias our esteemed colleague xarax) and I will attempt to cut various sections of the structure (eg collar) with a razor sharp blade while under load. Hopefully the act of cutting will not place my life at risk should the knot suddenly explode in my face! If I don't post back here again, it probably means that I am in heaven looking down upon X1 and smiling  :o

Mark

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on June 28, 2012, 06:38:13 AM
I will attempt to cut various sections of the structure (eg collar) with a razor sharp blade while under load.

This is a catastrophic idea / action ! :)  Are you sure you are going up, to heavens ?  :)

If not, I would suggest to simply untuck the tail / second leg of the collar, ( pull it out of the two nipping loops - so leave those nipping loops encircle and grip only the one, the first leg of the collar, the direct continuation of the eye-leg-of-the-bight ), and then measure what percentage of the initial maximum load of the complete bowline this "halved-bowline" can now bear.
(I expect that we will be surprised by the numbers in the cases of the Water bowline and the Gith-hitched bowline. I also believe that the initial separation of the two nipping loops would  matter quite a bit. If they are placed close to each other in the first place, they will have a greater chance to remain close to each other during the whole phase of the loading. In such a case, the " half-bowlines" would be able to withstand a much heavier loading, I guess. ).
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on June 28, 2012, 10:29:14 AM
Quote
It has made interesting reading going back over this topic again.  I learned a lot from other posters, but I am afraid that I still cannot countenance the concept of a Myrtle bowline or a Sheepshank bowline, so to preserve my sanity I will abstain from further discussion on the subject.

Derek

Heh Derek,

The only reason I posted images of the that weird structure called a 'myrtle' and the sheepshank was purely to show some more bight components and nipping turn components. I certainly did not intend to suggest that these structures are 'Bowlines'.

I am continuing to look at structures that have these core elements (ie bight + nipping turn) - simply so I can test the theory and see if it holds up.

In my view, the primary features of a Bowline include:
1) possessing a fixed connective eye loop.
2) does not jam under load and can be easily untied - even after a high loading event

If the specimen knot cant meet these first 2 criteria, it wont even be a contender for 'Bowline'.

The sheepshank is instantly dismissed - it doesn't pass the first test (no fixed connective eye loop).

As for the 'Myrtle' - that photo I uploaded is an abomination...I lifted it off the IGKT site - because I couldn't find any other images. I will re-photograph my own tying effort and re-present it in a proper orientation in accordance with Dan Lehman's notion of 'front' and 'rear' view.

Essentially, I am clinging to your theory regarding the bight component and the nipping turn component since it appears to me to be logical and elegantly simple. By adding the above 2 criteria, it appears to me to be a reasonable working hypothesis. As you know, all theories have to be tested.

I guess what I'm saying is that your absence from further commenting would be a significant loss...

Derek Smith:
Quote
I would make one comment which is hopefully constructive - you publish a strength test on the EBSB, declaring it to be ca 73% to 77% which implies that the knot is a significant improvement over the basic bowline.  But then one notes that the calculation is performed against the declared minimum rope strength - not the actual rope strength, so these results will have been overstated by some amount by which the tested rope actually exceeded the declared minimum value.  You would have made this test a little more valuable if you had included a test on the basic bowline under the same test conditions so a genuine comparison could have been made if indeed the EBSB is stronger than the basic.

Fair comment... from memory, I had a tight budget and limited time during the period of these original tests. I purchased a limited quantity of accessory cord - and had to make some hard decisions on how best to utilize that quantity. I did consider performing break tests on "ABoK #1010" as a control, but didn't proceed because I also wanted to test the Rosendahl/Zeppelin + a few other knots. In the end, I ran out of time and cord and the tests ground to a halt. Also, a series of 3 pull tests is not sufficient - I should have performed at least 5 x tests to get a better statistical sample. Again, I went with 3 tests for the same set of reasons i outlined above (ie limited quantity of cord, limited time, limited money...). In any case, at least I was able to compare the 'EBSB variant' breaks against the manufacturers stated MBS...so it least I've got something of a (tiny) data set. I will try to find some time (and cordage) to go back and perform a control test on "ABoK #1010"...

Mark

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on June 29, 2012, 08:19:52 AM
Hi Mark,

Thank you for the compliment, but I am sure that I cannot contribute much more of value of your challenge.

When I first read your post title, I felt there was an answer and after much discussion, arrived at the proposal outlined back in post #164

1.  A Bowline is an end of line [note 1] fixed loopknot {.EyeKnot}
[note 1 - a Bowline may be tied inline on a bight, in which case the bight is considered as an inline device to create a doubled 'end of line' element]

and carry on a little with :-

2.  A Bowline is defined and described in ABoK as 1010

3.  A Bowline construction comprises a load line, a knot, a fixed loop and an end

4.  A Bowline knot has two components, a Half Hitch Component connected to the load line and a loop leg and a Bight Component connected to a loop leg and the end [note 2]
[note 2 - the Half Hitch component transfers load into both loop legs through the turn element and the high nip force generated causes frictional entrapment of the end.  The Bight component acts as the core for the Half Hitch component and stabilises it via its bight collar made around the loaded line]

5.  A Bowline's Operational characteristics are :- ...

6.  A Bowline's Usage characteristics are :- ...

7.  A Bowline's Historical characteristics are :- ...

8.  A Bowline's Aesthetic characteristics are :- ...

9.  ...

But now I realise that had your question been 'What defines THE Bowline (#1010), the above answer might have held, but when it comes to answering your actual question 'What defines A Bowline', then I am afraind I have to opt for a perhaps more cynical answer --

i.e.  A Bowline is defined by - History and the whimsy of the trade or user that names it.

As if by way of demonstration we have proposals of the Zeperlin Bowline and the Myrtle Bowline, let alone the whimsy from Dan and Constance of the 'Sheepshank Bowline'.

Anything can be called a bowline and if then pressed into use, the name will stick irrespective of structure, characteristics or topology.

It would be nice to think that the combined 'Knotterati' of the venerable IGKT could make 2012 the year to propose a consistent definition for Bowline and Bowline Variants, and in doing so take a large step forward in cleaning up a little of the chaos which litters the historical naming of knots.  Driving our standard into the ground and declaring that henceforth members of the IGKT would only use the term Bowline to describe knots which complied to xyz...  but perhaps even that one step would require the wearing of 'seven league boots' by most of our illustrious members.

Still, enough on the topic of definition, could I turn briefly to the thorny subject of the importance of the bight component, and your proposal to take a razorblade to a loaded #1010.  Instead, could I suggest that you simply make up #1010 with a very long bight collar (ca 10 diameters).  If you then load this knot SP to Bight loop leg, the colar will pull up and form a normal Bowline.  If however, you load the SP and the nipping loop leg, then you willl see the nipping loop rotate the bight legs into a nice slipping noose arrangement.  What you will have seen is the mode of failure for the Bowline when the bight collar becomes excessively elongated and the loop is then subjected to ring loading on the nipping loop leg.

Conclusion == the bight collar is an absolutely essential part of the Bowline knot.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on June 29, 2012, 09:20:11 AM
An interesting example of how loading can / will influence a basic knot structure is given by the Eskimo

(http://igkt.net/sm/index.php?action=dlattach;topic=3233.0;attach=7344;image)

The standard SB Core loaded from the SP into the side arm of the nipping turn, converts the nipping turn into a Carrick component which in turn holds and is stabilised by the bight collar.

We might denote this knot as a 'Half Carrick loop knot' which is a very close sister to the one in which the bight component is replaced with a round turn which then creates the Carrick/Myrtle loop knot.

Or if we are feeling perverse, we could call the Eskomo a Half Carrick Bowline and its sister the Half Carrick/Myrtle Bowline.

But then, as the Myrtle is the working shape you get when you load a simple Carrick, we might have to call the latter of these two loop knots the Half Carrick/Half Simple Carrick Bowline...

But then again, as the Myrtle is most easily made by making a Constrictor and passing the WE through the constrictor loops before pulling it up, we might have to call the Myrtle the Constrictor Bowline... which would make the Eskimo sister knot into the half Carrick/Half Constrictor Bowline...

Ho Hum

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on June 29, 2012, 10:57:46 AM
I suggest that you simply make up #1010 with a very long bight collar (ca 10 diameters).  If you then load this knot SP to Bight loop leg, the collar will pull up and form a normal Bowline.  If however, you load the SP and the nipping loop leg, then you will see the nipping loop rotate the bight legs into a nice slipping noose arrangement.

However, if you load the SP, and both the standing " bight loop leg"  and the " nipping loop leg at the same time, ( i.e, the "eye-leg-of-the-standingpart" and the " eye-leg-of-the-bight" , if we use your terminology), you will see what I mean. You will see how the ABoK#160 "half-bowline"  works, and how the Sheepshank "half-bowline" works, and how the "Hitch series" works !

( P.S. And this will prove to you that the bowline can work even if the legs of the collar are not crossed in any degree, and remain parallel to each other right after the U turn of the collar. So, there is no hitch element in the bowline, if we are looking for such an element in the tail - and there is no hitch element in the bowline, if we are looking for such a hitch element in the nipping loop either - because, of course, the nipping loop is a nipping loop, it is not a hitch !
The bowline does not have a hitch in it.
The bowline is a close relative of the Gleipnir, not of the Sheet bend.
I argue for some obvious simple things with my wife for 35 years now. I guess I can bear to argue with Derek the next 35 years, for the bowline !  :) :)))
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on June 30, 2012, 09:47:56 AM

However, if you load the SP, and both the standing " bight loop leg"  and the " nipping loop leg at the same time, ( i.e, the "eye-leg-of-the-standingpart" and the " eye-leg-of-the-bight" , if we use your terminology), you will see what I mean. You will see how the ABoK#160 "half-bowline"  works, and how the Sheepshank "half-bowline" works, and how the "Hitch series" works !

( P.S. And this will prove to you that the bowline can work even if the legs of the collar are not crossed in any degree, and remain parallel to each other right after the U turn of the collar. So, there is no hitch element in the bowline, if we are looking for such an element in the tail - and there is no hitch element in the bowline, if we are looking for such a hitch element in the nipping loop either - because, of course, the nipping loop is a nipping loop, it is not a hitch !
The bowline does not have a hitch in it.
The bowline is a close relative of the Gleipnir, not of the Sheet bend.
I argue for some obvious simple things with my wife for 35 years now. I guess I can bear to argue with Derek the next 35 years, for the bowline !  :) :)))

Hi Constant,

You have demonstrated a number of things quite nicely for me here.

First - you have called ABoK #160 a 'Half Bowline'.  In Ashley's description of of #160 he states "the end is easily pulled through the hitches whenever it is necessary to adjust the length" [emphasis mine].  Now if Ashley can see that these two components are hitches, and I see they are hitches, why can't you?  And if the 'Half Bowline' has a hitch component in it, then presumably so does the whole thing- vis #1010.

Second, without meaning to cause offence or antagonism, I think you may have missed my point re the colar experiment.  Mark was going to take a razor to the colar of a loaded #1010 to demonstrate if the collar had any function within the knot.  If the collar was not there, then even pulling up both legs as you advocate would result in the demonstration I proposed, i.e. the knot would collapse into a noose, while load on the end leg would simply pull it out of the knot because shedding load in the collar turn around the SP is an important part of #1010 functionality.

Finally, you agree with my earlier statement that this thread is a matter of opinion, or rather a matter of differing opinions, and while some of my opinions have been revised by accepting rational arguments, some 'others' remain obdurate and indifferent to rational argument, and while you and your lovely wife have the stamina to bicker over 'simple things' for 35 years,  you will not find my dear Constant that I share your tenacity nor your good wife's patience.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on June 30, 2012, 11:28:43 AM
In Ashley's description of of #160 he states "the end is easily pulled through the hitches whenever it is necessary to adjust the length" [emphasis mine].  Now if Ashley can see that these two components are hitches, and I see they are hitches, why can't you?

I believe that repetition is the mother of all learning, but I also believe that exceptions prove the rule ... :)

You have a theory, inherited from Ashley, that the bowline is related to the Sheet bend. No surprize here : A whole generation of knot tyers had inherited the same theory - I dare to say: they were brainwashed by this theory. To support this theory, you have discovered a hitch where there is only a nipping loop. Of course, now you can not say what a nipping loop is, and you have to call any nipping loop "a hitch"... I would nt be happy to be in your position - but your tenacity is impressive, indeed - that is for sure -, so I suppose you will elaborate this theory a little more, so it will start to look a little more plausible.

Well, I have said time and again that Ashley was wrong on this - as God himself was wrong, when He said that the ratio of the circumference to the diameter of a circle is 3 ( speaking about the dimensions of the circular basin at the Temple). I do not have to prove that π is not 3 for you to accept my point, do I ? :) One can not really argue with a mathematical theorem.

The nipping loop is not a hitch. When a bight has both its ends loaded, and it is nipping a line that goes through it, it is a nipping loop. When a bight has only one of its ends loaded, it is a hitch. BIG, HUGE difference !  :)

The false theory of the close relation of the Bowline with the Sheet bend was, in fact, initiated by Ashley, who had not paid much attention to ABoK160 and ABoK#161 as structures that could be evolved even further : that is why he missed the Gleipnir ! Had he met the Gleipnir, I am sure that he would have seen its close relation with the Bowline, at once.
The Gleipnir proved that the primary element of the Bowline is the nipping loop, and the secondary element the collar. If we did not know the Gleipnir, ( and the ABoK#160 and ABoK#161 ), we would be justified to see the relation of the Bowline with the Sheet bend, indeed, a relation that is more remote and less important that the relation between the Bowline and the Gleipnir.

I have stated time and again this simple distinction :
a. A hitch has one leg loaded and one not, because the second leg has gone under the riding turn, and has escaped as a free end. The hitch is asymmetric.
b. A nipping loop has both legs loaded, to a more or less same degree. The nipping loop is symmetric.
a, b., not even c ! SO simple...

Of course, we can find cases where the distinction is not so clear, where the second leg of a "hitch" which should not be tensioned, is not a free end either. Also, we can find cases where the second leg of the nipping loop leaves the crossing point with the first leg at a much larger angle - so it is not loaded as much as the first leg any more. Generally, the "hitch" is a more vague term than the "nipping loop" . In ABoK#1821, Ashley is calling even a complete overhand knot tied around a ring as a "Half Hitch".
What I have stressed is that the " nipping loop"  is a very fundamental element of knots, and it should not be confused with the " hitch" - which is another fundamental element. At a hitch, we have the one leg going UNDER the second, so the one leg is not loaded ( or it is now much less loaded) than the other. At a nipping loop we have two legs that touch or cross each other at a point- most of the times - but they remain loaded at about the same degree as they leave this  point.

So, any "half-bowline" DOES NOT have a hitch in it, and this is true for the Glkeipnir, the ABoK#160 and the Sheepshank. And if the Gleipnir, the ABoK#160 and the Sheepshank do not have a hitch in them, so, presumably, the whole thing , vis#1010, does not have a hitch  in it either.

If the collar was not there, then even pulling up both legs as you advocate would result in the demonstration I proposed, i.e. the knot would collapse into a noose,

The ABoK#160 and the Sheepshank do not have a (loaded) collar. Do they collapse into a noose ?

while some of my opinions have been revised by accepting rational arguments, some 'others' remain obdurate and indifferent to rational argument

I wonder what are the "some" and what are the "others" ! :)
(The fact that you feel you have to refer to a line in a holy bible as some kind of " proof", tells something about the " rational"  :) character of your arguments. )

Constant
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 01, 2012, 12:27:37 AM

I have stated time and again this simple distinction :
a. A hitch has one leg loaded and one not, because the second leg has gone under the riding turn, and has escaped as a free end. The hitch is asymmetric.
b. A nipping loop has both legs loaded, to a more or less same degree. The nipping loop is symmetric.
a, b., not even c ! SO simple...

Constant

So then, let us take a little look at this So simple distinction.

In THE Bowline #1010, the SP enters the knot bearing 100% of the load.  If we ignore any load shedding as the SP passes under the collar, then we may assume that the SP enters the Nipping loop with virtually 100@% load.

So by your definition, the Nipping loop which is ( b. A nipping loop has both legs loaded, to a more or less same degree. The nipping loop is symmetric.), so in practice the nipping loop within the Bowline fails your stipulated definition, and is therefore not a nipping loop (even though it clearly is...)

Furthermore, you have stated that (The hitch is asymmetric.), so as the nipping loop in the Bowline is asymmetric (unless the Bowline is ring loaded 100% onto the SP loop leg), then the Bowline nipping loop is asymmetric and is by your definition a hitch...

As you see Constant, making definitions can be a bitch, but at least you are trying to justify your opinion.

Anyway, to end this argueing over a name, let me rename the component to the Single turn Component - and please dont forget - it is not a bend or a hitch or any recognised knot - it is a component...

Happier now?

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 01, 2012, 02:39:09 AM
I guess that YOU are happier- but that does not makes you less wrong... :)
You have carefully expanded your "stipulated"  counter - argument into many words and paragraphs, trying to make it look reasonable. Well, many words do not make a false claim true - unfortunately.
In an "ideal" bowline, where there would be no friction, what you describe is what would have happened, indeed. The nipping loop, being in equilibrium ( as the tension forces on the one leg would be the same with those on the other) , would have been free to move , to "walk", to wherever the eye-leg-of-the-bight would have dragged it - i.e., downwards, towards the tip of the bight. And this is what is happening even in this not-so-ideal world ( where knot tyers do not understand each other...), when the ropes are very slippery ( Spectra/Dyneema) and the load is very heavy. It has even been documented in videos, but you have forgotten to mention it...
When there is friction, and the loads are not so heavy, the nipping loop can not walk down the standing part, because it can not rotate around the legs of the collar that penetrate it. If the pair of legs of the collar , on the one hand, and the rim of the nipping loop, on the other, were not "glued" together due to friction, if they behaved like the two parts of a ball bearing - the one free to rotate in relation to the other - then the nipping loop would have been incapable to prevent the bowline to shrink like a noose, indeed.
So, the one leg of the nipping loop does not squeeze the other underneath anything, as the one leg of a hitch does to the other. The fact that the 100% of the load on the one leg becomes 50% on the other HAS NOTHING TO DO WITH THE INTERACTION OF THE TWO LEGS, as it happens in the case of the hitch. It is due to the friction between the rim of the nipping loop and the two legs of the collar ( the continuation of the eye-leg-of-the-bight, and the continuation of the tail ). If there would have been no friction there (or if we had been able to insert a roller bearing between the nipping loop and those two legs that go through it ), the nipping loop would have walked down the standing part, right till the tip of the bight .
I understand that you have jumped out of joy when you have discovered this apparent counter-argument of yours...Well, next time you should better try harder ! :) And with fewer words, because if something is true, it penetrates deeper into your opponents happiness if it is brief. I would have said that :
" The 100% of the load on the standing part becomes the 50% of the load on the eye-leg-of-the-standing-part. So the nipping loop is, according to your definition, not a nipping loop, but a hitch." Period
To which argument, I would have replied as such:
" The reduction of the load on the nipping loop s legs, from the 100% to the 50% has nothing to do with the one leg riding over the other and absorbing a part ( or the whole) of its load, as it happens in the case of the hitch. It is due to the friction between the rim of the nipping loop and the pair of the collar s legs that penetrates the nipping loop. Were there no friction there, the nipping loop would have walked down towards the tip of the loop, dragged/pushed by the collar, because the tensions on each of its two legs would have been perfectly equal."

Derek, we are both trained as engineers, but it seems we have been going to different schools together !  :)
What brings peace in my mind is this ; Whatever we say, any paradoxes we are discovering the one to the other s theory, are only subjective. The real world is there, independently of our semantic blah-blah, and works fine ! The bowline works, thank KnotGod, and neither me nor you can change this by arguments, however "rational' we think they are. Oh, yes, when I see the real world, when I see a bowline or a Zeppelin bend working, I am happier !  :)

Constant
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 01, 2012, 04:57:44 AM
" Single turn component" for the part of the bowline I call "nipping loop" , sounds fine to my ears...It describes something that makes a turn, but also something that can turn, that can rotate. A "nipping loop" on a tensioned line can rotate, and "walk" towards the one or the other direction. In the case of the bowline, it tends to walk downwards, towards the tip of the loop, because that is the direction to which the collar and the eye-leg-of-the-bight drag it, the first pushing it from above and the second pulling it from below.
Why this does not happen in the real world ? Why does the nipping loop remain fixed, placed at one point of the standing part, even if the collar and the eye leg of the bight are pushing and pulling it downwards ?  Because of friction. But not because of the friction between its two legs, as it happens in the case of a hitch. Because of the friction between the rim of the nipping loop and whatever penetrates through the nipping loop, i.e, the two legs of the collar.
Of course, the nipping loop squeezes the two legs of the collar together, the one upon the other, and this forces them to behave as a more or less unified object. However, this is something that can be achieved with the help of other means - with a bowline s simple "lock", for example. Let us suppose that this has been achieved already, and that the two legs of the collar are "glued" together, metaphorically or literally !  :) If that is so, now these two legs can drag the collar, and the collar, by its turn, can push the nipping loop. What will happen ?
In an " ideal" world and in an"ideal" knot, where there is no friction, the push of the rim of the collar will force the nipping loop to rotate around the axis formed by the legs of the collar, just like the outer rim of a ball bearing rotates in relation to the inner one. Rotating like this, the nipping loop will walk down the standing part, and nothing will stop it from reaching the tip of the bight - and the bight itself to shrink, like a noose, and finally disappear !
However, this is not what happens in the real world, thank KnotGod ! Because of the friction between the rim of the nipping loop ( the rim of the wheel) and the legs of the collar that go through it ( the axle of the wheel), the nipping loop can not rotate, so it can not walk, even if it is pushed by the collar from above, and it is pulled by the two legs of the collar from its centre. Of course, friction is all over the place. There is also friction between the two legs of the nipping loop, and between the rim of the nipping loop and the two legs of the collar. However, those effects are less pronounced, and secondary, I believe This is indicated, if niot proven - by the fact that a " half-bowline " where the nipping loop will not open up into a helix, will work surprising well, even without the help of a collar ( with a very loose collar, or even with a collar bight cut into two !) The two nipping loops, in the cases of the Water bowline, the Girth-hitched bowline, the ABoK#160,161 and the Sheepshank, do not need a collar to remain closed - and so they work very well, because their nipping loops, although they are pulled toward one direction, will NOT walk on the line. The lines around which they are " turned" prevent them from rotating, and so they can not move.
We all have played with such toys when we were kids, but it seems we have forgotten it ! :).  If we make a " turn"  with a string around a pencil, and keep the two ends of the string tensioned, we can "walk" the pencil from the one end to the other - provided the pencil is very slippery, or we enable this "axle" to rotate freely into our palm as we drag it towards the one or the other end. If the string is tensioned, if it does not slip on the surface of the pencil, and the if the pencil itself is not allowed to rotate the turn will not move, even if the pencil is pushed or pulled. I have called such a toy a "half-bowline", and its main component as "nipping loop", but I will be also happy with the name of a "single turn component". The Double bowline has a "double turn component", and the particular double, crossed nipping loops bowline I have presented yesterday will be a loop based upon a " double crossed turns" component, or something like that, I guess.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 01, 2012, 12:45:07 PM
It would be interesting to study the " single turn component " of the bowline knot in isolation, independently from the presence of the collar.

Let us first examine the simplest case, where :
a. the " single turn" is a 360 degrees turn around one round object - be it a pencil, or a one or more segments of rope, held there by the nipping action of the turn, by being glued together, or whatever.
b. the two legs/limbs of the turn are aligned - they leave their contact point to opposite directions. So, the former standing end and the former eye-leg-of-the-standing-part lie on a straight line.
c. the turn itself and both its legs/limps lie on the same plane.

This picture is only approximative, of course.  In fact, even in this case, the turn is but a helix, only this helix has the smallest possible pitch, of one rope diameter. So the turned rope is never a ring, it is segment of a helical coil, although the helical path of this coil has a small pitch, in comparison to its width. To speak of a plane on which this 360 degrees turn lies, it is only a convenient abstraction, for the sake of a simplified description.
As the reader who was brave and patient enough would have read by now, in the two previous posts, if we push this turn to the one or the other direction, it will rotate together with anything it encircles, and so it will "walk" alongside the tensioned line. ( However, if it is NOT free to rotate around the objects it encircles, or if these objects are NOT free to swivel around themselves, it will NOT walk ! That is why the turn of bowline does not walk towards the tip of the bight ).
Here comes the interesting part. What will happen if, instead of keeping the plane of the turn parallel to the tensioned line, we twist it a little bit ? ( Twist it so that  the two legs/limps of the " single turn component" are also twisted around each other, and get are more embraced around their contact point, not less. We wouldn't twist it so that it would open up to an open helix ...)
It is evident that, as we twist the plane of the turn in relation to the tensioned line, around the contact point of its two legs/limbs, the friction between the legs would start to get greater and greater. So, the rotation of the turn and its walk  alongside the tensioned line would now be restrained more and more by friction forces betewwn the two legs/limbs. On the area around the crossing point, the two legs would now be forced to embrace each other more, along a longer segment, and this will induce greater friction inside the whole rotating and " walking"  mechanism.
When the "single turn component" of the bowline knot is twisted ( due to the direction of the lines that pass through it, or for whatever other reason that has to do with its position/orientation inside the knot s nub), then it remains more steadily fixed on a certain point of the standing part, and it does not run the danger to walk downwards, towards the tip of the bight. So, a clever effective strategy is to force the plane of the turn to twist more, to settle to a position where it would be as much inclined in relation to the standing end axis as possible. At some point, we may argue that we should not speak of a common s bowline s turn component any more, but of a crossing knot s turn component. That transformation would be more evident if the turn is also re-positioned upwards or downwards, so that a large part - or the whole- of it lies well above or below the crossing point. In that case, we have a genuine crossing knot bowline.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 01, 2012, 01:49:11 PM

Derek, we are both trained as engineers, but it seems we have been going to different schools together !  :)
What brings peace in my mind is this ; Whatever we say, any paradoxes we are discovering the one to the other s theory, are only subjective. The real world is there, independently of our semantic blah-blah, and works fine ! The bowline works, thank KnotGod, and neither me nor you can change this by arguments, however "rational' we think they are. Oh, yes, when I see the real world, when I see a bowline or a Zeppelin bend working, I am happier !  :)

Constant

Hi Constant,

No, I am not an engineer, that accolade is yours not mine, I am a chemist.

I am sorry that you found my post excessively lengthy, I try to communicate clearly and so use however many words I feel are necessary to eliminate ambiguity.  After all, there is no point in posting words if all they do is confuse.

I am glad that simply changing the name of the component has resolved your problems with it.  However, it is worth mentioning that if I take four of these components, I will have created the Frictionless hitch...  Indeed, If I use cordage and former with a suitably high coefficient of friction, I could produce a Frictionless hitch out of just one Single turn Component and in that special case the component would indeed be the hitch.

The concept of 'Hitch' is a weak one, historically featuring cordage bound to a non cordage static object, but many instances show that a 'hitch' can be made to cordage objects as well.  Indeed, in compound cordage constructions, one part of the construction can be 'hitched' to another, so is it not reasonable that the term could be extended to describing the hitching of one component of a knot to another?

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 01, 2012, 04:24:39 PM
I am sorry that you found my post excessively lengthy,

If you read carefully, you will see what I had meant...It was not the length itself of your previous post that bothered me. After all, my posts are 10 times as lengthy !  :).    It was the style, which was sarcastic a little bit, like you have just uncovered an obvious mistake of a pupil, and you are proud to reveal this fact piece by piece to the poor boy... Well, you could have said what you said in just 2 lines, and I would have answered in 4. And you should have learned by now that I was not mistaken, so the style missed its purpose...I do make mistakes, A LOT of them, but not sooo silly like a mistake in addition of 50 +50... !  :)  You forgot to take into account the friction between the rim of the turn and the two legs of the collar that penetrate it. If the mechanism could work without friction on this particular point, it could have not been in equilibrium, and the turn would have started walking on the tensioned line, and would have reached the tip of the bight in no time ! So, when the mechanism is encountering yet overcoming friction forces and it is moving,  you can not expect a neutral sum of the forces that act on it, like this 50% + 50% = 100% you have stated in your comment. I know that most people would be surprised by a "single turn" component of the bowline walking along the standing part, but this is exactly what would have happened had it be no friction between the turn s rim, the wheel, and pair of the collar s legs, the wheel s axle. If you glue the two legs together, and pass them through a ball bearing, and then roll the turn around this ball bearing, as soon as you load the bight the one leg will wind around the rim of the bearing while the other will unwind , the turn, as a whole, will move towards the direction the collar pushes it, and the bowline will be transformed in a " double turn component"  at the tip of the former bight !

it is worth mentioning that if I take four of these components, I will have created the Frictionless hitch...  Indeed, If I use cordage and former with a suitably high coefficient of friction, I could produce a Frictionless hitch out of just one Single turn Component and in that special case the component would indeed be the hitch.

Yes, the two " half hitches" will hold almost everything, and the four "half hitches" will hold anything ! A series of "single turns" , where each single turn is not a hitch, behaves like a compound hitch - because the last leg would be completely untensioned, i.e.free.
However, I have to point out  this : A sufficiently large number of wraps around a pole, will behave like a hitch also ! I guess that 8 wraps will hold anything, and this has to do with friction and the capstan effect. Should we call a single wrap " a hitch" ?  :) It is exactly the same : When examined in isolation, both the "single turn" and the "single wrap" are not hitches, but a sufficiently large number of then makes them behave like a compound hitch, indeed. I prefer to examine each and every individual component in isolation from the others, that could well interfere with it and generate something new, something that was not expected to happen. If it happens, it happens because of accumulation of friction forces, not because of something inherent in the individual component. So, I will not call "a hitch" any such component, even if their superposition behaves as a hitch, indeed.

Constant
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 01, 2012, 08:18:23 PM

If it happens, it happens because of accumulation of friction forces, not because of something inherent in the individual component. So, I will not call "a hitch" any such component, even if their superposition behaves as a hitch, indeed.

Constant

Hi Constant,

I know that you know me well enough not to think that I was descending to sarcasm, so I am relaxed that on that score you are simply playing the torment.

However, on the above quote, I am afraid I do not understand what you have said, so I will paraphrase my suggestion.

If I hang 100 kg on a single turn of cordage which has a coefficient of friction of 1.1 against its static bar, then the weight of just a few inches of cord will be sufficient to hitch the 100kg load on the SP (see capstan equation with cfs set to 1.1, a 360 degree turn give a thousand fold shedding of the load into the bar).

In this situation the load is effectively hitched using only the Single turn Component.  Under this special case, do you accept that the Single turn Component is then a hitch?

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 02, 2012, 02:21:20 AM
...the weight of just a few inches of cord will be sufficient to hitch the 100kg load on the SP .
In this situation the load is effectively hitched using only the Single turn Component.  Under this special case, do you accept that the Single turn Component is then a hitch?

I have to repeat that a genuine " hitch component"  has its two legs asymmetrically loaded, because of the interaction of the one leg upon the other. In a hitch, the first leg goes over the second, as a riding turn, and the result of this interaction is the effective hitching of the second leg - and of the whole knot mechanism, in relation to the object around which it is warped. So, in a hitch component:
1. The one leg is loaded, while the second is not.
2. This asymmetry is due to the position of the one leg relatively to the other.
A " single turn component", on the other hand, has its two legs symmetrically loaded ( more or less). These two legs do cross at a point ( the crossing point), and they can even twist the one relatively to the other, to a certain degree. However, even if this symmetry is not absolute, we can not say that the one leg is less loaded - to some degree- than the other, because it is effectively hitched by its passing underneath the other ( as we have said in the case of a " hitch component") . So, in a single turn component :
2. This symmetry may not be perfect, but broken to a certain degree. However, that is not due to any asymmetry in the position of the two legs relatively to each other.
I believe that, in the past, even if I could not define with the precision I would have wished what was a nipping loop and what was a hitch, I could tell what was what the moment I saw one. Now, with this "single turn component" and this " hitch component" , I am not so sure any more !  :)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 02, 2012, 10:12:37 AM

The friction coefficient is irrelevant, you could have supposed a pole/bar of a sufficiently large diameter, whatever the friction coefficient is.

Hi Constant,

You have made the same mistake with the capstan equation that I did when I first came across it, but then I could be excused because I am not an engineer.  The capstan frictional effect works by the effect of cord tension force acting inwardly on the capstan and is a function of angle of contact not length of contact.  You will see from the capstan equation there is no diameter factor, only angle of contact in radians and the coefficient of friction -

(http://notableknotindex.webs.com/formula3.gif) from http://notableknotindex.webs.com/friction.html (http://notableknotindex.webs.com/friction.html)

So as in the Simple turn Component the contact angle is fixed at roughly 6.28 radians, contrary to your statement that the "friction coefficient is irrelevant", it is in reality, the only aspect which matters...

Your 'whole world' analogy you propose does not apply to the capstan effect because in the whole world case the frictional force is generated by gravitational attraction - i.e. the weight of the cord - not from tension.

You have mentioned the 'nipped tail' aspect of some hitches - this is an important positive feedback mechanism and perhaps we should consider this as a micro component or a component variant - what do you think?

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 02, 2012, 12:52:08 PM
As the reader would have understood by now, I think that the "nipped tail" is exactly what characterizes the "hitch component". It is the ONLY mechanism that can transform a "single wrap" component into a "hitch"  component. So, it is the only geometric characteristic that is different between the "single turn" component and the "hitch" component - the other characteristic, that is not shown in the pictorial representations of those two quite different things - is, of course, the asymmetry in the loading of the legs. ( With the provisional term "single wrap" component" I mean something like the "single turn" component, but where only the one leg is loaded. I repeat, in a 'single turn" component, both legs are loaded, to the same , more or less, degree. In a :"hitch" component, only the one leg is loaded, the other has been transformed into a more or less free end. (Derek Smith will probably figure out a more appropriate name for this " single wrap" element, I guess.)
I can not see how a " turn" , in general, could function as a "hitch" , without incorporating this 'nipping tail" characteristic. This is exactly how the one leg can "absorb", in a sense, the load that would otherwise have been transported throughout the other leg. So, it is the only geometrical transformation required, with the help of which  a "single turn" component to be turned into into a " hitch" component - the mechanical transformation required is the loading of only the one, not the two ends.
Now, of course there are more complex hitches that do not use this " nipping tail" trick... but another way to prevent the slippage of the second leg through the knot s nub, at a first stage, and off the object, at a final stage. I was only considering the most simple case, of the most simple rope path, able to hitch/be hitched around an object, and so be able to remain stationary even if only one of its two leg is loaded.

(2012-6-3 P.S.) I have edited my previous posts, by removing anything that had to do with an analogy / joke I have made about the very large friction forces on a very long rope, laid upon a flat (or warped around a round) Earth !  :) The fact that - as the " capstan equation"  and Derek Smith show-, even the very light load of the weight of short segment of a chord one the one leg can withstand any very heavy load on the other leg - provided that the rope is warped around a round object a sufficiently large number of "single turns"- does not, in my view, forces us to call a multi-warp system by the generic name of "a hitch". The mere accumulation of friction forces by the repetition of many turns can serve to attach a line on a pole or rope, indeed, it can serve to attach a line on an object, it can play the role of a  hitch -  but, at least according to my view of what is a knot (1), it is not a knot - so it is not a hitch, therefore and we should not call it "a hitch". Why it is not a knot ? Because it can be untied, without any obstacles imposed by the topology, the friction, or the mere bulk of the rope. What is prevented by friction ( by the capstan equation and by Derek Smith  :))  is its motion/rotation, as a whole, around the encircled object - or the motion/rotation of the encircled object around it . The multi-warp system is not entangled within itself in a way that would allow us to call it " a knot" .
However, we could well call a single wrap as a " hitch component" ( when it is loaded only from the one leg ),  just as we call a 360 degree bight around an object  "a single turn component" ( when it is loaded by both legs ) - although nor the " single wrap"  nor the " single turn" are genuine knots, in the sense described above. They are elements of knots, and when the knots do have a certain name, these elements can well shear the same name.
Then, why I do not wish to call this " single wrap" element/component, a " hitch" element/component ? Because I think that it is better, and more convenient, to reserve the use of this name for the case where we have a riding turn over a tail - the first one ( the loaded) leg going over the other, and squeezing it in between the riding turn and the surface of the encircled object.. Out of this embrace, this second leg walks out as a free end - well, more or less, this is but a simplified,  general, abstract picture. In this picture, there is a geometrical characteristic that distinguishes it from a "single warp", this asymmetric position of the two legs relatively to each other, which is the cause of the difference in the loadings -  the one leg is loaded ( and remains loaded), while the other is not ( because it does not) .
I believe that, if we keep in our mind those simple distinctions, we can analyse a certain knot in a more useful way, in order to reach a point where we acquire a deeper understanding of how this knot works, in particular, and how knots work, in general. A " single warp component", a " hitch component" , a " single turn component" - after all, it is not rocket science!  :)

1)   http://igkt.net/sm/index.php?topic=3610.msg20611#msg20611
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 02, 2012, 06:01:05 PM
I have not said that the friction coefficient is irrelevant ! ! ! I know very well what the capstan equation is ( and it is only an approximative function, of a very simplified description of what really happens !). I said that the friction coefficient is irrelevant in relation to your argument ! You could have used the same argument, without specifying the friction coefficient as you did, by only supposing a sufficiently large drum.
If you like to learn something more about the capstan equation, please, do not read it from the poor source you have cited !  :)(The Wikipedia article is correct, and much more informative. ) If you still believe that the radius of the drum does not matter, you are excused...You are a chemist !  :)

Hi Constant,

I am not an engineer, so I am guessing that the mistake is mine.  But I went to the source which you quoted as being superior http://en.wikipedia.org/wiki/Capstan_equation (http://en.wikipedia.org/wiki/Capstan_equation) but still found no mention of radius of the object, only exactly the same as Roo's web page -

The formula is:

T_\text{load} = T_\text{hold}\ e^{ \mu \phi} \,

where T_\text{load} is the applied tension on the line, T_\text{hold} is the resulting force exerted at the other side of the capstan, \mu is the coefficient of friction between the rope and capstan materials, and \phi is the total angle swept by all turns of the rope, measured in radians (i.e., with one full turn the angle \phi =2\pi\,).

I know that Wikipedia sometimes has several pages on the same subject, can you give me the link to the more informative source you refer to.

I think your 'whole world' model is descending beyond analogy/joke.  Not only would your hypothetical world have to be 'empty, but it would also have to be stationary, because without gravity and spinning at 24,000mph, the cord would fly off into space kissing goodbye to any hypothetical capstan effect.

Re you apparent need for a nipped tail in order to call a fixing a hitch, the so called Tensionless Hitch does not need a nipped tail, the load being shed through the capstan effect into the static object providing that the coefficient of static friction is high enough.

Constant, I have read your posts now for some considerable time and consequently I know full well that your command and comprehension of English is excellent (probably better than my own), so I cannot accept any excuses that we have a language barrier here.  Either the capstan formula does, or does, not include a radius function, in which case your assertion is either right, or wrong (with or without f's).  As you are the engineer here, I believe the onus is upon you to educate the chemist by pointing me at the appropriate reference to demonstrate your claim, and explain to me where I am misreading the science.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 02, 2012, 08:56:11 PM
... the so called Tensionless Hitch does not need a nipped tail, the load being shed through the capstan effect into the static object providing that the coefficient of static friction is high enough.

I will not go as far as to call this mechanism a " hitch", I prefer to call it a single or a multiple warp.  A sufficiently large number of single warps, around a cylindrical drum of a sufficiently large diameter, tied on a rope with a sufficiently large coefficient of friction ( one can consider any combination of those parameters ) can, indeed, function as a hitch, that is true. However, that should not force us to use the "hitch" name anywhere we have such an accumulation of friction forces, that at, the very end, would inevitably lead to a knot and an object entangled together in one whole.
Of course, literaly, and if you are ready to use far-fetched analogies, a "tensionless hitch" is a hitch. However, I can imagine many other rope mechanisms which would be able to function as hitches, if they include an  extreme number of turns, extreme rope dimensions and extreme friction coefficients. It would be better, and more convenient, if we reserve the use of the generic name "hitch" to situations that resemble the hitches we see in everyday life.
So, to my view, a "hich component" is something that includes, as a sub-component, or as an essential part,  this "nipping tail component" you are talking about. The turn of the rope here plays the role of a riding turn, The one leg is the continuation of this riding turn and the other is sqeezed underneath this riding turn, in between the riding turn and the surface of the object (or the rope, if the "hitch component"  is tied around one ore more rope diametres ). The one leg which forms the riding turn is nipping the other, which is the tail, so we have an asymmetry in the relative positions of the two legs, so the second leg is squeezed at some point, but at the end walks out of this embrace as a free leg ! :) One leg loaded, one free, the loaded leg making a riding turn, the other leg escaping under this riding turn, as a not-loaded leg . That is the general picture of a 'hitch component" I have in my mind...
Does this picture resembles a nipping loop, a "single turn component" ? I believe not, and I have tried to explain my view with/at the lengthy previous posts. The "single hitch component" has two legs loaded, to the same, more or less, degree. We can not speak of a tail. Any "hitcing effect " is only a colateral one, it is NOT due to the assymmetry of the two legs, either the asymmetry of their position, or the assymmetry of their loading - like what happens in the case of the "single hitch component".
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 03, 2012, 09:02:16 AM
The fact that - as the " capstan equation"  and Derek Smith show-, even the very light load of the weight of short segment of a chord one the one leg can withstand any very heavy load on the other leg - provided that the rope is warped around a round object a sufficiently large number of "single turns"- does not, in my view, forces us to call a multi-warp system by the generic name of "a hitch". The mere accumulation of friction forces by the repetition of many turns can serve to attach a line on a pole or rope, indeed, it can serve to attach a line on an object, it can play the role of a  hitch -  but, at least according to my view of what is a knot (1), it is not a knot - so it is not a hitch, therefore and we should not call it "a hitch". Why it is not a knot ? Because it can be untied, without any obstacles imposed by the topology, the friction, or the mere bulk of the rope. What is prevented by friction ( by the capstan equation and by Derek Smith  :))  is its motion/rotation, as a whole, around the encircled object - or the motion/rotation of the encircled object around it . The multi-warp system is not entangled within itself in a way that would allow us to call it " a knot" .
However, we could well call a single wrap as a " hitch component" ( when it is loaded only from the one leg ),  just as we call a 360 degree bight around an object  "a single turn component" ( when it is loaded by both legs ) - although nor the " single wrap"  nor the " single turn" are genuine knots, in the sense described above. They are elements of knots, and when the knots do have a certain name, these elements can well shear the same name.
Then, why I do not wish to call this " single wrap" element/component, a " hitch" element/component ? Because I think that it is better, and more convenient, to reserve the use of this name for the case where we have a riding turn over a tail - the first one ( the loaded) leg going over the other, and squeezing it in between the riding turn and the surface of the encircled object.. Out of this embrace, this second leg walks out as a free end - well, more or less, this is but a simplified,  general, abstract picture. In this picture, there is a geometrical characteristic that distinguishes it from a "single warp", this asymmetric position of the two legs relatively to each other, which is the cause of the difference in the loadings -  the one leg is loaded ( and remains loaded), while the other is not ( because it does not) .
I believe that, if we keep in our mind those simple distinctions, we can analyse a certain knot in a more useful way, in order to reach a point where we acquire a deeper understanding of how this knot works, in particular, and how knots work, in general. A " single warp component", a " hitch component" , a " single turn component" - after all, it is not rocket science!  :)

1)   http://igkt.net/sm/index.php?topic=3610.msg20611#msg20611
[/quote]
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on July 03, 2012, 10:41:01 AM
Thanks Constant,

I think you have something there.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 17, 2012, 07:24:01 PM
Here is what I have described as a "double, crossed-nipping - loops bowline".
A "bowline ? ? ? Without a "proper" collar ? ? ? The collar of the standard bowline, where the two legs that penetrate the nipping loop are almost parallel to each other ?  What happened to the aphorism "no "proper" bowline collar = no bowline" ?
There were two things that persuaded me to use this description - which I had denied earlier for the ABoK#1033 "Carrick" bowline-like loop.
1. This loop is very similar to the standard double bowline - the only difference is that the second nipping loop is placed in between the first nipping loop and the standing end - and not next to the first nipping loop, at its other side. The only reason the leg of the "not-proper" collar does not enter into the nipping structure from the same side from which it had left it, is a security precaution. In the past, I used to tie this loop with a "proper" collar, as a "proper" double bowline. However, I had noticed that there were cases where the second nipping loop (that should have remained in between the first one and the standing end ), sometimes went over it , and, as a result, the loop degraded into the standard double bowline. The great benefit of this "crossed nipping loop" configuration is the self-stabilization of this nipping structure, that relieves the collar of any relevant duty. This is possible only if the second nipping loop retains its position in the middle between the standing end and the first nipping loop. The particular "not-proper" new path of the working end in this "new" knot separates the two nipping loops permanently, so their relative position remains fixed under any loading conditions.
So, the great similarity of this loop with the standard double bowline, was the first reason that made me move against my earlier statements.
2. Now, there was also something fishy in my earlier position, that I knew right from the start, but I had hoped it would have remained under the carpet - so it would not complicate matters much more than they already are... I was eager to accept a generalization of the notion of the "nipping loop", so that it would be able to cover the standard double nipping loop, as well as some other similar double "nipping structures" ( like the Pretzel double nipping loop, for example ). However, when it came to the "collar" , I had accepted a much more restricted strategy : I had wished to name as a bowline only a loop that used a "proper" collar, i.e. a collar similar to the collar of the standard bowline. I have though/feared that, if we would have accepted different, more general types of collars, we would have been forced to describe as " bowlines" too many loops... that do not "look" like the standard bowline to most people.
The problem with this noticeable difference of how broad a definition we use for the "nipping loop structure"  and for the "collar structure" , is simple : The main/principle element of the bowline is the nipping loop. So, if we accept the use of more general nipping loops, can we deny the use of more general collars ? Accepting a broad, loose definition for the main part, and a narrow, tight definition for the secondary part, does not seem such a great strategy to me... :)
That was the second reason which made me to name this "double, crossed-nipping-loops" bowline-like loop as a 'bowline". Of course, if there would be a contrary consensus on this matter, I would continue to call this loop as a "bowline-like" end-of-line loop, as I did till now, not as a 'bowline" - just as the ABoK#1033.

We have four distinct strategies : The first is to have a broader concept of the collar ... and the second is to have a broader concept of the nipping loop... The third is to have both, and the fourth is to have none of them... I will not hesitate to adopt the one or the other, or both, or none, provided this will help us to study better the knots we already know, and the knots we are going to learn, if we adopt any one of the those four strategies.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 18, 2012, 11:16:42 PM
2. Now, there was also something fishy in my earlier position,

Oh, yes.    ;D

Quote
...  I was eager to accept a generalization of the notion of the "nipping loop",
so that it would be able to cover the standard double nipping loop, as well as some other similar double "nipping structures" ( like the Pretzel double nipping loop, for example ). However, when it came to the "collar" , I had accepted a much more restricted strategy : I had wished to name as a "bowline" only a loop that used a "proper" collar, i.e. a collar similar to the collar of the standard bowline. I have though/feared that, if we would have accepted different, more general types of collars, we would have been forced to describe as " bowlines" too many loops... that do not "look" like the standard bowline to most people.

I'm less concerned about look than fundamental function
--hence, look towards (only) the central nipping loop as
the essence of "a bowline".  But my fish tale wags, too,
in not recognizing the problem of tacitly accepting various
things as "a nipping loop", when I should be vigilant against
them, at least as acceptance w/o comment.  E.g., even
the common double/round-turn bowline must be noted
as having something other than a simple "nipping loop"
--it has a coil.  --and so, too, the water bowline and many
other constructs one can think of.  For these, though,
we might establish a means to recognizing them in their
place of *kinship* to the canonical "bowline"!?

What I did realize, at least, was that some of the
bowlinesque eyeknots I've discovered should be held
as "false" (or some better, more accepting qualifier)
bowlines --they've much the look & feel, etc.,
but deviate in the full nature of their nipping loop
--in that it doesn't directly flow into the eye (and
thus bear that 50% of tension one would expect).

Your outline of "strategies" for our nomenclature is good,
and we should proceed at least in classifying things into
various groups, w/o concern about whether that group
is later considered fully part of *bowline* or rather some
*like-a-bowline* naming : the group will stand together
regardless, distinct from other groups, later to see if
they share one or have more nominal umbrellas.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 19, 2012, 12:59:45 AM
some of the bowlinesque eyeknots... should be held as "false" (or some better, more accepting qualifier) bowlines -- they've much the look & feel, etc..,
but deviate in the full nature of their nipping loop--in that it doesn't directly flow into the eye (and thus bear that 50% of tension one would expect).

To flow directly into the eye, is much less than 50% of the "full nature" of the standard, common bowline s nipping loop ! The nipping loop of the bowline works as effectively as it does, because it is the direct continuation of the standing end ( the loaded end), which bears 100% of the the tension - and not because it is the direct continuation of the eye leg of the bight, which bears 50% of the tension. Having one of its limbs tensioned by 100% of the load, the nipping loop can grip the leg(s) of the collar with full force.
At the double, crossed-coils "nipping structure"  of the loop shown in the previous post, the ( first, main) nipping loop/coil grips the second leg of the collar as effectively as the nipping loop of the standard common bowline, because one of its limbs ( the direct continuation of the standing end ) is also tensioned by the 100% of the load. The other limb flows into the second nipping loop/coil, that is squeezed in between the first nipping loop/coil and the tensioned standing end - therefore it bears less than 50% of the tension. However, I do not believe that this fact diminishes the gripping power of the first, main nipping loop substantially - or that it makes this nipping structure deviate from the true "nature" of the nipping loop of the standard, common bowline.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 19, 2012, 11:24:52 PM
Let us examine the "Sheet bend "bowline"" - the end-of-line loop derived from the Sheet bend ( shown at the attached pictures).
If, in order to call an end-of-line loop "a bowline", we do not demand the existence of the "proper" collar of the standard, common bowline, then I am afraid that we will be forced to call this loop "a bowline", too. Now, to my view, although this loop might superficially "look" like the bowline, it works in a very different way. Its not-proper "collar" is, in fact, nothing but a half hitch, and the second leg of this collar/hitch is not nipped inside the nipping loop s ring ( as it happens in all bowlines). Moreover, the nipping loop itself is not a closed ring, but an open one ( although it is not as open as the helical coils of the "helical loops", shown at (1),(2).
So, here is an end-of-line loop that, although we may say that it "looks" very much like a bowline, indeed, it functions very differently, as two interlinked half hitches - or three interlinked half hitches, if we take into account all the three limbs of this knot. Now, the standard common bowline does not function like this - it is a close relative of the Gleipnir knot rather than the Sheet bend. Neither the "proper" collar, nor the "proper" nipping loop of the common bowline are "half hitches" ! This is an example of the difficulties we will encounter if, in order to generalize the notion of the "bowline", we do not pay much attention to the characteristics of the collar structure, and we are ready to accept more general "collars"  than the "proper" bowline s collar.

1) http://igkt.net/sm/index.php?topic=3020.msg21688#msg21688
2) http://igkt.net/sm/index.php?topic=3020.msg23685#msg23685
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 21, 2012, 04:05:25 AM
some of the bowlinesque eyeknots... should be held as "false" (or some better, more accepting qualifier) bowlines -- they've much the look & feel, etc..,
but deviate in the full nature of their nipping loop--in that it doesn't directly flow into the eye (and thus bear that 50% of tension one would expect).

To flow directly into the eye, is much less than 50% of the "full nature" of the standard,
common bowline's nipping loop ! The nipping loop of the bowline works as effectively as it does,
because it is the direct continuation of the [SPart], which bears 100% of the the tension
--and not because it is the direct continuation of the eye leg of the bight,
which bears 50% of the tension.

I disagree : the nature of the "nipping loop" is that it is
exactly that : a loop --with consequent implications!
Otherwise, one has any sort of thing coming into play,
and, i.p., one can have a "hitch" (component) as you ascribe
to the sheet bend --100% feeding into 0%/free tail!

Quote
Let us examine the "Sheet bend "bowline"
-- the end-of-line loop derived from the Sheet bend ( shown at the attached pictures).

Well, most people regard the bowline as derived from
(or kin to) this end-2-end knot; but the asymmetry of the
latter enables two *directions* for eye derivation.

Quote
Moreover, the nipping loop itself is not a closed ring, but an open one
( although it is not as open as the helical coils of the "helical loops", shown at (1),(2).

And that fact might be what casts it out of the group.
(There are some "anti-bowlines" that tend towards
helical vs. "closed ring" geometry --and, indeed, we
have even examples of this in the common bowline(!)--,
but they do so by forces upon the nipping loop, and not
by the physical presence of another part impeding closure.)

So, superficial "looks" should be discarded as a criterion.

Quote
Now, the standard common bowline does not function like this
--it is a close relative of the Gleipnir knot rather than the Sheet bend.
Neither the "proper" collar, nor the "proper" nipping loop of the common bowline [is a] "half hitch" !

And nota bene that the revered Gleipnir has no "proper collar"!
You might find my accommodations about collars consistent
in this essence?  --that whatever structure sustains the nipping loop
serves to keep the eyeknot in candidacy for bowliness ?!
;)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 21, 2012, 12:34:12 PM
the nature of the "nipping loop" is that it is exactly that : a loop --with consequent implications!
Otherwise, one has any sort of thing coming into play, and, i.p., one can have a "hitch" (component) as you ascribe to the sheet bend --100% feeding into 0%/free tail!

Of course, a nipping loop should, at the first place, be a loop. However, all loops are not nipping loops... The "generic", "perfect" nipping loop should be loaded from both legs. Moreover, those legs should barely touch each other - otherwise the total sum of the tensile forces that are supposed to flow into the nipping loop s ring by both legs is diminished. If the tensile forces are "wasted" at  the crossing point between the two legs, the total gripping potential of the nipping loop is also wasted.
Those conditions do not happen in real life. No nipping loop is a "perfect" nipping loop ! We try to have nipping loops that utilize as much of the tensile forces present at the outer ends of both their legs, as possible. If the one (second) leg of the nipping loop flows directly into the eye of the bight, that is good, because we are assured it will be loaded by 50% of the total load - most of the time. However, if the other (first) leg does not flow directly into the standing end, that advantage can be wasted, because this leg would not be loaded with 100% of the total load. Given that wasting a certain percentage of the 100% of the total load is more severe than wasting the same percentage of the 50% of the same  load  :), I am more concerned with what happens before the first leg, than what happens after the second leg. If the flow of the standing end into the first leg of the main nipping loop is not direct, the nipping potential of this loop on the penetrating legs of the collar(s) would be severely wasted, and the negative result would be much more important than the result of a similar situation on the other (second) leg.

Well, most people regard the bowline as derived from (or kin to) this end-2-end knot...!

Well, most people are wrong...  :) And I believe that they are wrong because they have been brain-washed by Ashley, for too much time !  :) Had Ashley put the two loops side by side, and pin-pointed their obvious differences, this thread would have been MUCH shorter. Those two end-of-line loops are two altogether different animals, and that is what I am trying to say, over and over again, right from Reply#2, 275 posts ago ! The bowline is a Gleipnir or a ABoK#160  or a Sheepshank with a "proper" collar, while the "Sheet bend loop" is more of an entanglement of three half hitches...I always hope that Derek Smith would modify his theory, otherwise we would miss an opportunity to analyse the bowline in more detail than we were doing two thirds of a century ago.

There are some "anti-bowlines" that tend towards helical vs. "closed ring" geometry ...
but they do so by forces upon the nipping loop, and not by the physical presence of another part impeding closure.

I should have stressed that I was speaking about the dressed and tensioned by hand knots only...Under heavy loading, the geometries vary - unfortunately, I have not been able to examine heavy loaded and/or capsized bowlines till now...

So, superficial "looks" should be discarded as a criterion.

Right ! Please, keep it in mind, and tell it also to Derek Smith, and all people that keep telling that the bowline is something of a Sheet bend transformed into a loop...

You might find my accommodations about collars consistent in this essence?  --that whatever structure sustains the nipping loop serves to keep the eyeknot in candidacy for bowliness ?!

A very general - and I may add quite bold, too - view of the bowlineess...It will lead to a definition of what I have called "collar structure " as a structure that might not involve any "collar" at all, nothing that "looks" like a "collar" - be it the "proper" common bowline s collar, or not.
Up until now, I have called such loops as "bowline-like" end-of-line loops, meaning that the moment the "collar structure " is pulled out of the standing part, the knot degenerates into the unknot. ( Notice that the "collar structure " might not even be necessary for the integrity of the "nipping structure" under moderate loading - as I have seen in the case of the "double, crossed nipping loops bowline" presented at (1). ) However, this was a consideration of the topology of the bowline, not its behaviour under (heavy) loading. To go as far as to characterize by "collar structure " anything that serves to stabilize the nipping loop,even if it does not look like a collar at all, or to disregard the "collar" element and concentrate on the "structure" , is a very bold movement, that only a few knot tyers would be ready to follow. The bowline is the king of the knots, no question about it, a marvellous thing that should come first in any knot compilation. Millions of people know it by its name, are able to recognize it and to tie it. This fact puts a certain limit on the generalization we may offer to the notion of the bowline. I have seen that the community of the knot tyers is conservative - to my view, too conservative...-, so will it accept such a very general characterization of its most used and admired loop ?

1) http://igkt.net/sm/index.php?topic=3233.msg23683#msg23683
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 26, 2012, 11:48:33 PM
There are two forms of the common bowline : the "left-handed" and the right-handed""  one. Similarly there are two forms of the "Eskimo" bowline, the left-handed and the right-handed.
Right ? Wrong !  :) The two legs of the collar of the standard, common bowline remain almost parallel to each other - just like the penetrating-the-nipping-loop rope segments at the Gleipnir, the ABoK#160 and the Sheepshank. On the contrary, the two legs of the collar of the "Eskimo"  bowline are crossing each other, at an angle of about 90 degrees. (The more round the bight of the loop, and the larger the angle between the two legs of the bight of the loop, the smaller is this angle. At 120 degrees, it is almost zero - just as at the common bowline). So the second leg the collar ( the tail), can pass over or under the first leg ( the continuation of the eye-leg-of-the-bight). That means we do not have two, but four different forms of the "Eskimo" bowline.
It can be seen that, when the second leg of the collar, the tail, passes under the first, it gets itself into a position where it is squeezed in between the first leg of the collar and the rim of the nipping loop - so, at the end, we have a "hitch-like" knot, and a most effective prevention of any slippage of the tail.
Therefore, from the 4 different forms of the "Eskimo" bowline, the two -where we encounter this "hitch-like" configuration between the two legs of the collar- should, presumably, be more secure than the other two. I guess that the difference should be quite apparent with very slippery material ( like Spectra and Dyneema) - but I have not made any relevant experiments.
Now, I  have noticed that the Sheet bend "bowline", -the bowline-like loop mentioned at Reply#275 (1), with its "not-proper" collar and "not-proper" nipping loop - is the "reversed" form of one of the two "hitch-like" "Eskimo" bowlines  (2). Does this mean anything ? Probably not - but I have imagined that the "Eskimo" bowline might have been discovered accidentally, when somebody would have grasped the (long) tail - instead of the standing end - of a "Sheet bend "bowline", and has realized that this "reversed" loop could also hold very well.  I guess that the standard bowline is probably a later refinement of the Sheet bend "bowline" - because the "proper" collar and the "proper" nipping loop would have not been such obvious solutions to the knotting problems of our ancestors, as they seem to us now. .. In fact, the "proper" collar and the "proper" nipping loop are quite advanced, sophisticated, maximally evolved and simplified rope mechanisms, where any redundant element has been omitted. The Sheet bend "bowline" looks much more primitive, naive, because its not-proper collar and its not-proper nipping loop have not reached their final, maximally simplified, perfect form.

1) http://igkt.net/sm/index.php?topic=3233.msg23702#msg23702
2) However, this "Eskimo" bowline is not the one that seems to be the most secure of the four forms .
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on August 13, 2012, 11:11:19 AM
We all understand the difference between the bowline-like end-of-line loops based upon a single "proper" nipping loop knot, and those based upon a single crossing-knot. The problem is that, if we do not consider the end-of-line loops based upon a crossing-knot be included in the family of the bowlines, we run the danger to exclude the "Eskimo" bowlines as well- and this is something that the knot tying community is not ready to acept ( And, it is a debatable issue, because, when the angle of the two legs of the loop is greater than 120 degrees, the "Eskimo" bowline behaves exactly as the common bowline. See Reply#118, (1))
One possible escape is to narrow the definition of the crossing-knot based end-of-line loops, so that it will not include the "Eskimo" bowlines any more. Then, we can exclude those more narrowly defined crossing-knot loops from the family of bowlines, without throwing away the baby with the water - the "Eskimo" bowlines with the not-so-bowline-like crossing-knot loops. I know that this is a compromise, and as such, it will not satisfy 100% anybody ( except me - perhaps :)).
So, we can define as a "proper" crossing-knot loop a loop based upon a particular knot, where the standing part touches the nipping loop s rim for a second time, at a second point. Then, we can exclude this family of end-of-line loops from the family of bowlines, reduce the number of loops that are considered as bowlines, but at the same time leave the "Eskimo" bowline in its traditionally occupied place.
At the double nipping loop end-of-line loops, where we have a second nipping loop, we will consider as "proper" crossing knot loops only the loops where the standing part touches again the rim of the nipping loop from which it has just left, i.e. before it has formed the second nipping loop. So the Constrictor based loop(s), for example, will continue to be considered as bowline(s), along with most of the "8" shaped, double-nipping-loop based knots.

1) http://igkt.net/sm/index.php?topic=3233.msg19858#msg19858
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 13, 2012, 08:33:06 PM
We all understand the difference between the bowline-like end-of-line loops based upon a single "proper" nipping loop knot, and those based upon a single crossing-knot. The problem is that, if we do not consider the end-of-line loops based upon a crossing-knot be included in the family of the bowlines, we run the danger to exclude the "Eskimo" bowlines as well- and this is something that the knot tying community is not ready to acept ... .
One possible escape is to narrow the definition of the crossing-knot based end-of-line loops, so that it will not include the "Eskimo" bowlines any more.
...

I'm unmoved.  There are fuzzy boundaries no matter
--consider the potential for the common bowline to capsize
into what might be called a "helix-based" knot (that with
a broad, helical curvature in the SPart as it passed through
the nub), and that other knots we'd (or at least *I*) like
to regard as "bowlines" have similar potential transformations
under load and with various dressings.

.:.  I think that we must simply accept that fuzziness exists,
that the (sub)sets are close & interlinked by degree.  We
might find that overhand-based knots come next to ask
association and by similar arguments of proximity.  Maybe
under some *discomfort* in the setting out of all of this
we find some way to tighten definitions ... , but at time
time, I see nothing compelling in that.  (Just setting out
all of the knots --grouping & classifying put aside or as
mere conveniences to the task of enumeration-- will be
an accomplishment (and exhausting, if not overwhelming).

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Sweeney on August 13, 2012, 09:35:03 PM

Maybe under some *discomfort* in the setting out of all of this
we find some way to tighten definitions ... , but at time time, I see nothing compelling in that.  (Just setting out
all of the knots --grouping & classifying put aside or as mere conveniences to the task of enumeration-- will be
an accomplishment (and exhausting, if not overwhelming).

I have watched and sometimes marvelled at the development of this thread which so often seems the pursuit of a definition y for its own sake.  "Bowline" is simply a word applied now and in the past to a knot and extended to more knots by qualification (eg double bowline) - and it is now extended to a family of knots for no obvious purpose.  I would agree with Dan as above - there is some merit in setting out all knots which have some link however tenuous to a bowline - but the link to a bowline serves only to make such a task feasible by drawing a (fuzzy) boundary. Logical extension of this is to try and identify all knots and simply give avery one a designation. the fact that a knot has relatives or not has no relevance whatsoever because it is a human perception not based on anything but a desire for order. I know that Dan has a penchant for a description in words of eg how to tie or describe a knot - I do admire that - but give a computer a set of pictures and it will find a match in a very short time as long as a reference picture is available. In short defining the bowline is as big a waste of time and effort I have seen in recent years - but it's not my time or effort so carry on by all means.

Barry
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on August 13, 2012, 11:56:32 PM
I'm unmoved.
I see nothing compelling in that.

I was sure you would have not (be moved, or see something compelling), but for other reasons : If we prefer to classify knots by their functions/mechanisms, and not by their looks/appearances, we can not distinguish the crossing knots from the "proper"crossing knots I propose - where the leg of the nipping loop does touch the nipping loop s rim another time, at another point ( not the "crossing point" of the nipping  loop). The crossing-knot is a knot where the second leg does not run directly at / is not a direct continuation of, the eye-leg-of-the standing part of the loop, as the first leg comes directly from the standing end / is a direct continuation of the standing end. Instead, it makes a more or less sharp turn, because, when it leaves the nipping loop s rim, it has a direction "upwards" i.e., it could not have reached the tip of the bight had it not made this turn.
However, I think that I have "succeeded" to reduce, a little bid, the number of what we can consider as end-of-line loops that belong to the class of bowlines - and I have done it in an unambiguous way : It is easy ( NOT fuzzy) to see if the standing end or the eye-leg-of-the-standing part touches the rim of the nipping loop a second time, or not !  :)
I am very happy that I have removed a considerable number of ex-bowlines from my (large) bowlines picture file, and have sent them to the (smaller) crossing-knot end-of-line loops file !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on August 14, 2012, 12:44:58 AM
so often seems the pursuit of a definition for its own sake.

Seems, may be, but it is not ! Definitions CAN NOT exist for their own sake, even if we wish them to be so : they pre-suppose deep understanding, and they prove superficial knowledge. Names are not just labels - otherwise every thing in this universe would have had another name !  :) The first name was not arbitrary either : the bowline was called bow-line to describe the line with which a boom of a certain sail was attached to the bow of the ship. The fact that the name "bowline" was given to other "similar" knots is also not a coincidence ! It was an extension based upon some objectively defined characteristics. So, if we see a knew knot, that "seems" like THE bowline, it is only natural to think if we better call it also a bowline, or not. Sorting things according to their characteristics, getting sets, and classes of sets, that are fewer than the things of the universe, is a necessary function of every more or less intelligent creature in the universe ( and, I wish to believe we belong to the set of such creatures... :) )

it is now extended to a family of knots for no obvious purpose.

"Not obvious" may be, but it IS for a purpose, believe me. The effort of classification of known knots has lead us, time and again, into a deeper understanding of how they function, and - what is more useful - to the "invention" of new, better knots. You classify things and, suddenly, you notice a "hole" in the data, which should not be there, according to the scheme. It s natural to think : Hey, may be there is a knot that would fill this void -let us see if we can modify the existing knots that are next to it, and see what happens. It is the same procedure that lead Mendele?ev to its "periodic table of chemical elements", and the subsequent discovery of new elements that have filled all the voids of the initial plan.
Personally, I am unable to remember how to tie and to use a knot, if I do not understand it a little bid...And when I had succeeded to understand a knot a little more, it had happened to me to be lead to new knots, that I was not aware of till this time. So,not a waste of time or effort for me - if we suppose that ANY time and effort spent on knots is not wasted, since the invention of the glue, the button, the zip, and so on !  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Benboncan on August 14, 2012, 12:11:54 PM
Quote
What I did realize, at least, was that some of the
bowlinesque eyeknots I've discovered should be held
as "false" (or some better, more accepting qualifier)
bowlines --they've much the look & feel, etc.,
but deviate

In Biology the above description could result in a name beginning with pseudo. Is this appropriate for Bowline-like (esque) structures that don't quite make it?

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Benboncan on August 14, 2012, 01:16:15 PM
Quote
In short defining the bowline is as big a waste of time

I disagree, definitions reduce ambiguity. Without them a reader or listener has to guess at meaning.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on December 14, 2012, 02:13:06 PM
Definitions do reduce ambiguity, that is true, but, unfotunately, they can not reduce doubt... :)
So, is this knot a (-) bowline, or not ? ?  I call it "Sheet bend "Eskimo" bowline / bowline-like loop " , until somebody comes with a better suggestion. Its similarity with the "Sheet bend common bowline / bowline-like loop (1) is obvious, but its difference might not be so. As an "Eskimo"-bowline-like loop, it can withstand ring loading. Moreover, it can be tied by a quick tying method, as a lockable noose-hitch - similarly to the "common" version (2).

1.   http://igkt.net/sm/index.php?topic=3233.msg23702#msg23702
2.    http://igkt.net/sm/index.php?topic=4162.0
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on December 14, 2012, 02:33:41 PM
To me personally these latest don't require the "Bowline" moniker because they don't encompass the orientation of parts of the Standard bowline.

I feel that for it to include the name and be in the Bowline family it should have a nipping loop and a collar in the original locations and around the same parts. Any modifications to enhance the original should not obscure this. They can be doubled, retraced and added to, but those parts in the common locations should be there.

So for the best definition, take and tie a Standard Bowline, after that, view another eye-loop and compare the parts and orientations. Or do it in one's head.

For me that removes the ambiguity.

SS
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on December 14, 2012, 04:10:11 PM
Thank you SS369,

So, for you the "Eskimo" bowline is not a bowline ? Because, if it is a bowline, this one should also be a bowline :  The nipping loop on the standing part is there, in the same location, the eye-leg-of-the-bight enters into it through the same orientation as it enters into the nipping loop of the standard "Eskimo" bowline, and then it encircles the eye-leg-of-the-standing-part at the same location, too. Then, instead of making a "proper" "Eskimo" bowline collar, it makes a sort of a "Myrtle" collar, i.e., it crosses the nipping loop for the last time without penetrating it. Is this one and only factor the decisive factor ? Is the type of the collar, the specific way the last part of the tail is secured by the nipping loop, such an importand thing ?
I do not wish to abandon the name "bowline" for the "Eskimo" bowline too easily... I think I had managed to reduce the number of "bowlines", by defining the "crossing knot " loops ( or, at least, a large subset of them ) and then excluding them from the family - but the "Eskimo" bowline I wish to remain part of it, if it is possible ?

P.S. I have tied two Forms of "Janus" bowlines, that can illustrate the ( slight ? ) difference between the "prorer" "Eskimo" collar, and the collar of the Sheet bend "Eskimo" bowline-like loop shown in this last post. See the attached pictures. Woudnt it be a little far fetched, to deny that the "Fontus" bowline is so different than the other "Janus" bowlines ?
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on December 14, 2012, 04:43:30 PM
Hi X1.

Yes, it has the parts, but not the orientation. I would call it bowline-esque.

As tied in the accompanied picture (yours hopefully used with permission). I find it lacking security as compared to the (let's say) original bowline, tied in static 11mm rope. I tied the two in identical rope (the ends of the single rope), dressed and snug, and then just beat them around hitting the floor and whatever. The "normal" stayed secure where as the Eskimo nip loosened.
Not very scientific, but for a quick test it shows me some things.
I am not diss-ing the knot here I just don't think we need to call it a bowline.

Maybe I am being too critical, but I think an eye-loop just doesn't have to have "bowline" in the name.

I tied a loop knot the other day in front of a co-worker. It was just a overhand slip loop and he beamed with recognition and called it a Bowline! lol

Maybe the others can be called "Stern-lines".
;-)))

SS
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on December 14, 2012, 05:19:43 PM
Hi X1.

Yes, it has the parts, but not the orientation. I would call it bowline-esque.

We need context here : your reply follows an X1 msg. posted
after a prior post-&-reply, but nevertheless you seem to be
referring to the earlier and not immediately-above knots
--for those in the pure orange rope nearest above cannot
be faulted for orientation.

Quote
Maybe I am being too critical, but I think an eye-loop just doesn't have to have "bowline" in the name.

"eye loop" I deem a pleonasm : "eye knot" is my term
vice "loop knot"/"loop" --"loop" being so overloaded as
to be problematic, "eye" IMO w/o such issue (as used
e.g. in "eye splice", with no such "loop splice" around).

;)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on December 14, 2012, 05:25:53 PM
Definitions do reduce ambiguity, that is true, but, unfotunately, they can not reduce doubt... :)
So, is this knot a (-) bowline, or not ? ?

You mean the top, colored-rope knot?

Hmmm, I'd say that these knots (both) too much break
there being any real/in-effect loop part, with their
structure forcing that into more of a helix than it should
be for the category.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on December 14, 2012, 06:44:14 PM
I would call it bowline-esque.

I keep the bowline-like term to signify the PET feature of it. However, is there anything beyond this, that makes it akin to an (Eskimo) bowline ? That is the question.

I find it lacking security
I think an eye-loop just doesn't have to have "bowline" in the name.

So, are we going to call "bowlines" only the knots that do not "lack security"  ? Are we going to name a knot depending upon its supposed or proved qualities - or lack of qualities -, independently of its structural characteristics ? That is a very slippery road !  :) Knots would be named and re-named, if they hold or not on some specific materials, under some specific circumstances, patters of loading, etc.
I search for the characteristics of the mechanism, not for the qualities of it. A nut ans a bolt are a nut and a bolt, even if they are made by a very soft material ( boiled spangetti ? )  :)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on December 14, 2012, 07:00:59 PM
You mean the top, colored-rope knot?

I mean the knot shown in the post where this question was asked, the Sheet bend "Eskimo" bowline-like loop. ( See the attached pisture )

Now, if you try to name a knot, either the one shown in Re# 286, or the two shown at Re#288, based upon pottential quantities ( forcing it "more" or "less" to degenerate to a helix ), you do the same mistake as SS369 did : you judge the knot by its supposed or proven perfomance, not by its structure. ( And you forget what you have said elsewhere : what characterizes a structure being a "collar structure", is its ability to keep the balance of the nipping loop, to prevent it from degenerating into an open helix. There are collar structures which achieve this better than others - but we can not name as "collar structure" only the most efficient collar structure, as we can not name "a knot" only the most efficient knot ! :) )
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on December 14, 2012, 09:00:22 PM
Hi X1.

Yes, it has the parts, but not the orientation. I would call it bowline-esque.

We need context here : your reply follows an X1 msg. posted
after a prior post-&-reply, but nevertheless you seem to be
referring to the earlier and not immediately-above knots
--for those in the pure orange rope nearest above cannot
be faulted for orientation.

Quote
Maybe I am being too critical, but I think an eye-loop just doesn't have to have "bowline" in the name.

"eye loop" I deem a pleonasm : "eye knot" is my term
vice "loop knot"/"loop" --"loop" being so overloaded as
to be problematic, "eye" IMO w/o such issue (as used
e.g. in "eye splice", with no such "loop splice" around).

;)

I was replying to the instance of the "eskimo" bowline and not the previous knots specifically. There was an edit (X1) afterwards in which the Janus had been added.

My apologies for the pleonasm. It sometimes happens. Yes "loop" is overworked as is "eye",  so in my mind I threw them together as a slam dunk. ;-)

SS
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on December 14, 2012, 09:17:29 PM
I would call it bowline-esque.

I keep the bowline-like term to signify the PET feature of it. However, is there anything beyond this, that makes it akin to an (Eskimo) bowline ? That is the question.

I find it lacking security
I think an eye-loop just doesn't have to have "bowline" in the name.

So, are we going to call "bowlines" only the knots that do not "lack security"  ? Are we going to name a knot depending upon its supposed or proved qualities - or lack of qualities -, independently of its structural characteristics ? That is a very slippery road !  :) Knots would be named and re-named, if they hold or not on some specific materials, under some specific circumstances, patters of loading, etc.
I search for the characteristics of the mechanism, not for the qualities of it. A nut ans a bolt are a nut and a bolt, even if they are made by a very soft material ( boiled spangetti ? )  :)

Bowline-like term is OK as a descriptor, but, I don't think "Bowline" has to be part of the name. It is overworked.

The mention of the lack of security (I qualified that in part) is not significant to the naming.
Naming is subjective and has to pass muster throughout all the languages.
I do not think that some attribute of the knot in the name is a bad thing, e.g., Slipped Bowline, Running Bowline,etc. At least that can inform us of something.
Eskimo Bowline really tells me nothing.

I digress into knot naming, but that is part of the challenge here.

I stand by the statement that if the loop knot/eye knot has the basic form and orientation of the common bowline (ABoK#1010) then that is what I consider the bowline realm.
Those parts and that orientation are what do the work. Addons can enhance the knot as a whole, in some way or another.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on December 14, 2012, 11:26:18 PM
Eskimo Bowline really tells me nothing.

I was under the impression we should keep this name, if for nothing else, at least out of respect to "tradition" (?). However, I really do not know how "common" is this name, neither when it was first introduced, etc.
If it is decided that this name is not so deeply/well established, and we abandon it, then we can use the name/term "anti-bowline', proposed by dL, to denote the bowline-like (PET) end-of-line loops where the direction the working part has as it enters into the nipping loop is opposite to the direction it follows in the standard bowline,
( I believe I am less attached to any name than anybody !  :) I see complex "things"  as merely sets of physical characteristics, compiled by us for a purpose - as mental tools, as descriptions of experimental set ups, etc. They do not have any objective existence, other than the one our brain wish to endow them, to help us better adapt to our environment. So, a name is a tool of a tool of a tool - not so importand a thing, after all !  :) )
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on December 15, 2012, 12:09:55 AM
If the name "Bowline" (which is misleading anyway or doesn't describe the loop at all) will continue to be the nomenclature for the ABoK # 1010, then words (tools of communication) should be used to describe that knot accurately. Perhaps the parts in order of tying from the Standing Part to the Working End.(?)
Then we will have a definition, characteristics and topology. imo

Personally I am fine with retaining this particular name for this particular loop knot #1010). It is burned into memory and to unlearn is much harder. But, for newer knots to come (even) we can do better.
I think.

SS

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: kd8eeh on December 16, 2012, 02:20:52 AM
I'd just like to mention that X1's sheet bend-bowline like knots are simply a standard eskimo bowline (with what would be the tails on the inside of the loop) but loaded by what is usually the tail instead of what is usually the standing part.  For that reason, I would say it is a variant of a sheet bend, being that there is no true nipping loop in the in the standing part.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on December 16, 2012, 02:57:18 AM
[the] sheet bend-bowline like knot [is] simply a standard eskimo bowline... but loaded by what is usually the tail instead of what is usually the standing part.

Yes, so we could well refer to this knot as the "reversed" /" inversed" form of the Eskimo bowline. However, there are 4 variations of "the"(?) Eskimo bowline - and the mechanism of this particular knot is similar to the mechanism of the Sheet bend, and the Sheet bend bowline-like loop, presented elsewhere. That is why I chose to use this name - which, indeed, may sound a little odd...
Title: What prevents the "walking" of the nipping turn along the Standing Part ?
Post by: X1 on July 18, 2013, 01:50:24 AM
Regarding what prevents the "walking" of the nipping loop downwards, towards the tip of the eye, I had made the following "thought experiment" - in an effort to isolate and reveal the very mechanism that prevents it :
Imagine that you glue the two legs of the bight component ( the collar structure) together - but nowhere else. Now, the eye leg of the Tail side can not pull the Tail itself around the "capstan" of the Standing end, and out of the nipping turn.
Imagine also that, in between those two glued legs of the bight component and the rim of the nipping turn, you place a ball bearing, which prevents the slippage of the two legs of the bight component through it, on the one hand, but allows their rotation relatively to the rim of the nipping turn, on the other. That is, imagine that the nipping turn can prevent the bight component to slip through it, to be translated, but not to revolve within it, to be rotated.
Load the eye of the bowline. What will happen ?    The bight component, as a whole ( because its two legs are now glued together ), will tend to slip downwards. The friction forces at the Standing end - collar contact area are very small, and can not prevent this type of motion by themselves. Slipping downwards, the bight component will push the nipping turn from above, by the bulk of its collar, AND it will drag it along with it, by the friction of their mutual contact area -  because we have supposed it can revolve within it, but it can not slip through it - so the nipping turn, pushed from above, from its "head", and dragged by its rim, by its "waist", will start to "walk". The bight component will push and drag the nipping turn, but it can not / it will not follow its walking / rotating - for two reasons : First, nothing forces it to rotate ! : Even if/when the nipping turn rotates, as it starts "walking",  the ball bearing can not transfer this rotation from its outer ring, which is attached to the nipping turn, to the inner ring, which is attached to the legs of the bight component. Second, even if the bight component was forced to rotate, it would had not, because it could had not : we should never forget that the bight component can not rotate around its axis / revolve within the nipping turn, because the standing end that penetrates it, as a pin, at the region of the collar, does not allow this type of motion.
So, nothing will prevent the "walking" of the nipping turn, which, together with the bight component, will move downwards, and will consume the eye leg of the standing part side till the eye itself disappears altogether !
What prevents this from happening in the real bowline ? The friction between the nipping turn and the bight component, which, on top of everything else it achieves, it also prevents the nipping turn from rotating relatively to the bight component, and so it prevents if from "walking" - because the bight component itself is hindered by the standing end and can not revolve. It is the friction between the two elements of the bowline, the nipping turn and the bight component, what prevents the nipping turn from "walking'" - a potential movement of the nipping turn that people do not question why it does not become actual -  so they do not search for the mechanism that does not allow it to happen in the first place.
In this picture, I made a simplification, for the sake of the argument...There is also another mechanism that prevents the "walking" of the nipping turn, albeit a secondary one . The crossing point of the nipping turn is a "point" ( a small area )  where, for various reasons, the one leg of the nipping turn is squeezed on the other. For the nipping turn to be able to "walk", those two legs should be free to dis-engage and re-engage on each other, like the dents of two engaged gears, because the one feeds the Standing part, and the other is fed by it. During the "walking", the segment of the Standing part "above" the nipping turn is unwinding from its rim, and the segment "below" is winding around it. If those two segments, which meet at the crossing point of the nipping turn, are squeezed upon each other, and "bite" each other hard, and if they can not be dis-engaged and re-engaged again, the friction forces at this area will be enhanced, and the two segments will not be allowed to "walk" on each other - so the nipping turn itself, as a whole, will not be able to "walk" either.
Title: Re: Whar prevents the "walking" if the nipping turn along the Stanfing Part ?
Post by: Dan_Lehman on July 18, 2013, 07:47:15 PM
So, nothing will prevent the "walking" of the nipping turn, which, together with the bight component, will move downwards, and will consume the eye leg of the standing part side till the eye itself disappears altogether !
What prevents this from happening in the real bowline ? The friction between the nipping turn and the bight component, which, on top of everything else it achieves, it also prevents the nipping turn from rotating relatively to the bight component, and so it prevents if from "walking" - because the bight component itself is hindered by the standing end and can not revolve. It is the friction between the two elements of the bowline, the nipping turn and the bight component, what prevents the nipping turn from "walking'" - a potential movement of the nipping turn that people do not question why it does not become actual -  so they do not search for the mechanism that does not allow it to happen in the first place.

Except that, in fact, such slipping can be observed
in the real world --esp. in HMPE cordage, such as on
the video I've linked to elsewhere; but also, to some
lesser degrees, in other circumstances.  It is something
to consider for some of the more complex bowlines
in which increased number of parts returning to the
turNip imply a diminished proportion of load
--in theory, disregarding friction-- upon the SPart-side
eye leg (or eye-leg part, which might not feed
directly into the eye).

--dl*
====
Title: Re: What prevents the "walking" of the nipping turn along the Standing Part ?
Post by: X1 on July 18, 2013, 09:40:30 PM
...in fact, such slipping can be observed in the real world --esp. in HMPE cordage, such as on the video I've linked to elsewhere; but also, to some lesser degrees, in other circumstances.
Exactly ! :)   In the real world, when there is less friction between the two legs of the bight element and the rim of the nipping turn than it is required  /adequate to prevent this "walking" of the nipping turn under heavy loading of the eye, this "walking" will take place, indeed !
" It is the friction between the two elements of the bowline, the nipping turn and the bight component, what prevents the nipping turn from "walking'" .
Under heavy loading, when there is less friction, there is more "walking". When there would be no friction ( as in my "thought experiment" described previously, with the bearing inserted between the legs of the bight component and the rim of the nipping turn ) this "walking" would transport the nipping turn to the tip of the eye in no time.

increased number of parts ...imply a diminished proportion of load - in theory, disregarding friction
Not "disregarding friction" !
Friction theory tells us that friction force is independent  of the number of parts, i.e., the total contact area : Amontons' Second Law : " The force of friction is independent of the apparent area of contact."  However, my theory  :) :) :)  is that, with objects whose surface can be deformed under compression, creating "dents", things are even worse ! The less the area, the deeper the dents, the greater the enhancement of the "normal" friction force, described by Ammonton s laws. In particular, when two straight strands of rope are squeezed upon each, the friction force between them depends upon the angle they meet : Under the same squeezing force, the greater the angle, the less the area, the deeper the dents, the greater the obstacles to any slippage, the greater the "enhanced" ,by the deformation of the surface area, normal friction forces. In fact, it is not only a theory : I have seen this happening in real ropes, although I had not measured it. The greatest angle, the right angle, is the angle when the two ropes "bite" each other the deepest, so, regarding our intention to prevent slippage, it is the right angle, indeed.
So, when we wish to block slippage, multiplying the contact area by multiplying the number of parts in contact to each other is not beneficial to the enhancement of friction forces, and, most probably, it is detrimental to it ! The "increased number of parts" can slide on each other rather freely, because there are no deep dents, so the normal friction forces are not enhanced at all. No wonder that when the angle two adjacent ropes is almost zero, i.e. the ropes are almost parallel to each other, they can slide on their extended mutual contact area much more than in any other case.

So, what should we do ? : Two things :

1. Keep the number of parts as small as possible. In particular, I believe that a nipping turn encircling two rope diameters is blocking the slippage of any of them more efficiently than if it was encircling three rope diameters. However, we need the three rope diameters for other reasons, that are related to strength, not to security. A nipping turn that is encircling three rope diameters is almost circular, that is, it is more round, with fewer "weak" points of smaller curvature which can diminish the strength of the rope. ( Also, any one of the three strands that would be squeezed upon each other inside a nipping turn, would have a greater chance to meet an other at a greater angle - so to block more efficiently any one of them which will attempt to slip out ).

2. Make the parts meet each other at as a great angle as possible. The best we can do is to have them settled in a stable position inside the knot s nub, where they will meet at the right angle, the right angle.

Title: Re: What prevents the "walking" of the nipping turn along the Standing Part ?
Post by: Dan_Lehman on July 19, 2013, 04:18:16 PM
increased number of parts ...imply a diminished proportion of load - in theory, disregarding friction
Not "disregarding friction" !
Friction theory tells us that friction force is independent  of the number of parts, i.e., the total contact area ...

Yesssss, disregarding friction : you miss my point,
which is that the nip upon the tail-side *end* of
the turNip might be diminished and there could
be --YMMV per friction per material-- thus
still delivery of ("flow-through of") more force to
this part than is implied by the number of other
parts (through the turNip) that apparently bear
load "south" (eye-wards) of the nip --where the
SPart has it all, to the "north".

((I think that in practice there might be some
considerable slippage of the turNip'd parts with
and then comes more nip-grip of those parts,

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 25, 2013, 09:54:50 AM
We all have played with such toys when we were kids, but it seems we have forgotten it ! :) .  If we make a " turn"  with a string around a pencil, and keep the two ends of the string tensioned, we can "walk" the pencil from the one end of the string to the other - provided the pencil is very slippery, or we enable this "axle" to rotate freely into our palm as we drag it towards the one or the other end. If the string is tensioned, and if it does not slip on the surface of the pencil, and if the pencil itself is not allowed to rotate, the turn will not move / walk, even if the pencil is pushed or pulled.
Let me attempt to say the same thing, with MUCH more words - just in case somebody had read the above, but had forgotten it by now   :) :

There is one thing people forget about the bowline - and which must be obvious when the bowline is tied on a very slippery material, and/or loaded heavily  :
WHY THE NIPPING TURN DOES NOT "WALK" DOWN THE STANDING PART, towards the tip of the eye ?
Clearly, the friction between the standing end and the collar is not enough. Then, why ?
I have tried to show it with a little experimant : Take a string, make a nipping turn on it, make the nipping turn encircle a perpendicularly placed pencil, and keep the string tensioned constantly. Now, push the pencil, while keeping it parallel to itself, that is, perpendicular to the sting, towards the one or the other end of the string.
Surprise ! The pencil will be translated, because it can be rotated ! I did not say that you should nt allow it rotate, did I ?  :)
And by it being translated, the nipping turn will "walk" - meaning that the segment of the string coming from the one side will wind around the pencil more, and the segment of the string coming from the other side will unwind.
What can prevent the translation of the pencil ? The prevention of its rotation. What can prevent this rotation ?
In the example of the pencil, nothing. You were told to push the pencil, but not to prevent its rotation. In the reality of the bowline, where the ?pencil? is the two ( or three, in the case of double collar bowlines ) legs of the bight component, the fact that this bight component is attached,  re. rotation, to the standing end. It can not rotate around itself, it can not revolve, because of this standing end penetrating it at the region of the collar...
One would say : there is another way the pencil can remain un-rotated, but be translated nevertheless : if the string that turns around it slips on its surface, i.e. in the case of a very slippery or sweated pencil !  Well, yes, it can, in the example of the pencil, and when the student has not made its homework...
However, in the case of the bowline, there is sooo much friction between the shrinking squeezing nipping turn and the two or three legs of the bight component, that this poor bight component can not even think of been left free to rotate around itself / revolve !
So, at the end of the day, the nipping turn does not walk along the Standing part, because the standing end prevents the ROTATION of the bight component, and preventing rotation of the bight component means preventing translation ( preventing walking ) of the nipping turn.
Title: The use of the prefix anti- to denote the Eskimo-like bowlines, as anti-bowlines
Post by: X1 on July 25, 2013, 04:05:06 PM
The prefix anti- is used in English language to denote mainly two things :

1. Against, opposed to, preventing or relieving
2. Being in a state spatially opposite to another.

Its use in the case of the "Eskimo" bowlines was advocated by dan Lehman, who considered this characteristic as a very important quality of the "Eskimo" bowline, and its derivatives. It is true that we should distinguish between the "Common" bowlines, where the bight component collars the Standing end, and the "Eskimo" bowlines, where the bight component collars the eye leg of the Standing Part s side. Also, it is true that the side through which the eye leg of the Tail side enters into the nipping turn is very important. However, this distinction should be neutral, without any connotation that there is a confrontation between those two forms of the bowline. Just because I happen to live in a country where the prefic anti- in the words is used for many years, and many times each day  :) , I felt that the ambiguity would have to be pointed out. I had also proposed an alternative description, which uses, as prefixes, the corresponding notations (+) and (-), which sound more neutral to my ears.

I have counted the words in contemporary English language where the meaning of the anti- is the first :; a number close to 60.

antacid, antagonist, anthelmintic, antiaircraft, antibacterial, antibiotic, antibody, anticholinergic, antichrist, anticlerical, anticline, anticoagulant, anticodon, antidepressant, anti-diarrhoeal, antidiuretic, antidote, antiemetic, antifeedant, antiferromagnetic, antifouling, antifreeze, antigen, antigravity, antihero, antihistamine, anti-infective, anti-inflammatory, antiknock, antilock, antilogy, antimacassar, antinomy, antioxidant, antipathy, antipersonnel, antiperspirant, antipruritic, antipsychotic, antipyretic, antiroll-bar, antirrhinum, antiscorbic, anti-Semitism, antisense, antiseptic, antiserum, antisocial, antispasmodic, antistatic, antithesis, antitoxin, antitrust, antivenin, antiviral, antivivisection,.

I have also counted the words where the meaning of the anti- is the second : a number close to 10 ;

anthelion, anticlockwise, anticyclone, antilogarithm, antinode, antiparallel, antiparticle, antipodes, antistrophe, anti-symmetric,

The number of different words is not a proof, of course, that the one meaning is more or less frequently used than the other. However, the 6 : 1 ratio tells something, I believe...

This is the reason I do not like the anti-bowline characterization of the "Eskimo" bowline and its derivatives, and I prefer to use the (+) and (-) notation.
The interested reader is kindly requested to figure out a way of denoting diametrically opposed qualities, points, sides, locations, orientations, etc, without denoting any confrontation that supposedly, sooner or later, will be resolved by the dominance of the one over the other.

Contraria sunt Complementa    :) :)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 26, 2013, 01:25:04 AM
Myself, I prefer the term Offset Bowline.
Title: Re: The use of the prefix anti- to denote the Eskimo-like bowlines, as anti-bowl
Post by: Dan_Lehman on July 26, 2013, 06:50:58 AM
The prefix anti- is used in English language to denote mainly two things :

1. Against, opposed to, preventing or relieving
2. Being in a state spatially opposite to another.

Its use in the case of the "Eskimo" bowlines was advocated by dan Lehman, who considered this characteristic as a very important quality of the "Eskimo" bowline, and its derivatives. It is true that we should distinguish between the "Common" bowlines, where the bight component collars the Standing end, and the "Eskimo" bowlines, where the bight component collars the eye leg of the Standing Part s side. Also, it is true that the side through which the eye leg of the Tail side enters into the nipping turn is very important. However, this distinction should be neutral, without any connotation that there is a confrontation between those two forms of the bowline. Just because I happen to live in a country where the prefic anti- in the words is used for many years, and many times each day  :) , I felt that the ambiguity would have to be pointed out. I had also proposed an alternative description, which uses, as prefixes, the corresponding notations (+) and (-), which sound more neutral to my ears.

I have counted the words in contemporary English language where the meaning of the anti- is the first :; a number close to 60.
...
I have also counted the words where the meaning of the anti- is the second : a number close to 10 ;

anthelion, anticlockwise, anticyclone, antilogarithm, antinode, antiparallel, antiparticle, antipodes, antistrophe, anti-symmetric,

The number of different words is not a proof, of course, that the one meaning is more or less frequently used than the other. However, the 6 : 1 ratio tells something, I believe...

This is the reason I do not like the anti-bowline characterization of the "Eskimo" bowline and its derivatives, and I prefer to use the (+) and (-) notation.
The interested reader is kindly requested to figure out a way of denoting diametrically opposed qualities, points, sides, locations, orientations, etc, without denoting any confrontation that supposedly, sooner or later, will be resolved by the dominance of the one over the other.

Contraria sunt Complementa    :) :)

Partially correct : I use "anti-bowline" soley to distinguish
the direction of the tail's return through the turNip
--that is how the Eskimo bowline comes into the (sub)set,
nothing to do with its collaring an eye leg (but that is all
it can collar, given direction; but it could loop, instead).
It was "anti-cyclone" that I thought of, though the more
commonly used "anti-clockwise" should've come to mind.

Counting senses!  Well, maybe we should work towards
righting that imbalance!?  In any case, it was a convenient
moniker that had a rationale, and I wanted a label/name.   ;)

--dl*
====
Title: Re: What prevents the "walking" of the nipping turn along the Standing Part ?
Post by: Dan_Lehman on July 26, 2013, 07:04:22 AM
the nip upon the tail-side *end* of
the turNip might be diminished and there could
be --YMMV per friction per material-- thus
still delivery of ("flow-through of") more force to
this part than is implied by the number of other
parts (through the turNip) that apparently bear
load "south" (eye-wards) of the nip --where the
SPart has it all, to the "north".

((I think that in practice there might be some
considerable slippage of the turNip'd parts with
and then comes more nip-grip of those parts,

you miss my point

That was no sooo difficult, was it ?
Considering that I still miss it now, because you should be nominated
by the Pulitzer prize for those tangled "sentences" :
And sometimes I might cast a vote for that award, myself!  ::)

Partly, of course, the problem is that we don't have
a sound nomenclature for discussion --which in part
betrays the secret that knots haven't been very much

But let me try again.
"*end*" is something I use to denote a part exiting
some circumscribed area of interest; if that were
a nub of an end-2-end or eye knot, there would
be four "*ends*".  But it does sound like "tail",
which I try to use to mean "end" in the common
sense (and "bitter end", though I fight against
corrupting the sense of "bitter" deriving from "bitts").

But, let's break from this a moment and think of
the complex bowlines that have extra passes
of parts --the working end going back'n'forth--
through the turNip.  In the basic bowline
we think that each eye leg has 50% of the load
in opposition to the 100% of the SPart.  You have
remarked about the nipping loop wanting to walk
into the eye, and that points to the need for the
SPart's 100% to somehow be reduced to only
50% by time it exits into the eye.  Well, in a
sheet bend there is NO load on what would
be this continuation --the SPart turns around
the bight legs, nips its tail . . . : period!

I just wanted to suggest that in some of those
complex bowlines with now say 3 diameters,
i.e. 3 parts running through the central nip,
that the apparent distribution of force across
them all might not be so even, and that if
the usual 50% on that nipping loop's continuation
is diminished --by these other parts taking on load--,
there might be some slippage  & adjustment.
(And one might wonder if even there could be
such a change of mechanics to impart more
than 50% around the nipping turn?)

--dl*
====
Title: Re: The use of the prefix anti- to denote the Eskimo-like bowlines, as anti-bowl
Post by: X1 on July 26, 2013, 12:36:17 PM
Partially correct : I use "anti-bowline" soley to distinguish the direction of the tail's return through the turnip --that is how the Eskimo bowline comes into the (sub)set, nothing to do with its collaring an eye leg ( but that is all it can collar, given direction; but it could loop, instead).

You deny the most important thing that could had lead you to this characterization - the distinction between the direction/side the eye leg of the Tail enters into an already formed nipping turn, in the cases of the Common and the "Eskimo" bowline. This is what one has to pay attention BEFORE he makes the collar - so it is the most important distinction re. the tying procedure. Only AFTER he has followed the proper path, and AFTER he has collared the eye leg by forming an "Eskimo" collar, he can see that, in fact, following this and not the opposite direction, and entering through this and not the opposite side, he did the only thing he could do, in order this knot be stable. On the same token, only AFTER he has followed the proper path, and AFTER he has collared the Standing end by forming a "Common" bowline s collar, he can see that, in fact, following this direction and not the opposite direction, and entering through this and not the opposite side, he did the only thing he could have done, in order this knot be stable.

The direction / side through which the eye-leg enters into the nipping turn of a Common or an "Eskimo" bowline is MUCH more important, re. their tying process, than the direction / side through which the Tail enters into it !

Counting senses!  Well, maybe we should work towards righting that imbalance!?  In any case, it was a convenient moniker that had a rationale, and I wanted a label/name.   ;)

It is amusing that, of all the other members of the Forum, it as only me who spotted this "imbalance" - the only person that can happily live with it, because the anti- prefix, in about half of the initial / ancient and the present uses in his mother language, as well as all the geometrical / mathematical uses, is NOT imbalanced !  :)  Also, it is used many more times with the meaning of "instead", "in place of", than in English. The  Greek ancient and modern most common wordσ : αντι-κρυ, for example, meanσ facing, vis-?-vis, across / over the way, on the other side of. The word : αντι-περα means across, on the other side ( of the road, the river, etc,). The words αντι-θετο, αντι-στροφο, mean reverse. The word : αντι-κειμενο means object, and αντι-κειμενικα means objectively. Αντι-στοιχος means corresponding, equivalent, respective. And so on...

So, there are two things we should do :

1. Decide which is the most important thing : the direction / side through which the Tail enters into the nipping turn, OR the  direction / side through which the eye leg of the Tail enters into the nipping turn.
2. Find a ":balanced" label/name denoting this.

You will not only offer salads like this vegetarian "TurNip" of yours ! Cook a real food here ! ( the last one , the post-eye-tiable = PET, was edible / is digested...)

Title: Re: What prevents the "walking" of the nipping turn along the Standing Part ?
Post by: X1 on July 26, 2013, 12:53:38 PM

"*end*" is something I use to denote a part exiting some circumscribed area of interest; if that were a nub of an end-2-end or eye knot, there would be fourb "*ends*".

You forget that you had used the word "limb" for such a part - a more proper word, that denotes a protrusion . extension of a central body.

in some of those complex bowlines with, say ... 3 parts running through the central nip,
the apparent distribution of force across them all might not be so even.
if the usual 50% on that nipping loop's continuation is diminished -- by these other parts taking on load- -,
there might be some slippage & adjustment.
(And one might wonder if even there could be a change of mechanics to impart more than 50% around the nipping turn?)

Why do I understand it NOW ? Is it because I have drunk some magic anti-poison, and became smart overnight ?  :)
Thank you.

Title: Re: What prevents the "walking" of the nipping turn along the Standing Part ?
Post by: Dan_Lehman on July 26, 2013, 04:27:57 PM

"*end*" is something I use to denote a part exiting some circumscribed area of interest; if that were a nub of an end-2-end or eye knot, there would be fourb "*ends*".

You forget that you had used the word "limb" for such a part - a more proper word, that denotes a protrusion . extension of a central body.

in some of those complex bowlines with, say ... 3 parts running through the central nip,
the apparent distribution of force across them all might not be so even.
if the usual 50% on that nipping loop's continuation is diminished -- by these other parts taking on load- -,
there might be some slippage & adjustment.
(And one might wonder if even there could be a change of mechanics to impart more than 50% around the nipping turn?)

Why do I understand it NOW ? Is it because I have drunk some magic anti-poison, and became smart overnight ?  :)
Thank you.

Beware that I feel myself having gone in BOTH directions
on musing force distribution : that there is less on the
eye-side of the turNip --so, more to sheet bend forces--
and more --hmmm, I think thinking that somehow
there becomes less nip on that eye side exit.

Yes, "limb" is something uttered.  It seems to connote that
the nub is a unit, with *body* connotations; whereas "end"
looks to the nub as a tangle of 1-to-N pieces of flexible (knottable)
material, each of course having two "ends" (and the nub
having 2N ends).  If we were focused on some discussion
of knots in the *tangle* senses, more "theoretical" than
"practical", "ends" should come off perfectly well --as,
to a later part of the discussion, even remarking how
in a practical-knots dialogue, "end" comes with some
common sense that runs against my use above.

--dl*
====
Title: Re: The use of the letter Z to denote the Eskimo-like bowlines, as Z-bowlines
Post by: alpineer on July 27, 2013, 09:40:39 PM
S-bowline ( for the "Common" bowline ) and Z-bowline ( for the "Eskimo" bowline ?

It won't work X1. Why? Because coiling direction doesn't per se :) determine handedness. Because handedness doesn't determine whether a bowline is common or Eskimo. Take two separate cords and tie the bowline form. Same handedness produces both common bowline and Eskimo(offset) bowline versions. Said another way, one can produce the common bowline in both Right-Hand coiled and Left-Hand coiled versions, and of course vice versa for the Eskimo bowline.
Good try though. I've been spending some time thinking about this recently myself, specifically, how to define the Tresse Bowlines in less ambiguous and dyslexia resistant terms.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 28, 2013, 07:25:00 AM
It this convention that offers the opportunity to relate the handedness of the nipping turn to the direction the eye leg of the Tail as it enters into it, in the cases of the "Common" and of the "Eskimo" bowline.

And what is this relation of the nipping turn to the direction in which the 'eye leg of the tail' (sic) enters it?

Also, I don't support the re-labeling of front/rear views of the bowline. Doing so serves only to confuse matters unnecessarily. Naming convention doesn't affect which particular view of the bowline better shows it's routing. So, why bother? The argument for re-labeling is moot when one simply acknowledges that both aspects of a knot should always be shown.

P.S. It's 'tail side eye leg' and of course 'SPart eye leg' for the other leg.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 28, 2013, 07:22:09 PM
Reply #315 has been edited, hoping for clarity.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on July 28, 2013, 07:39:31 PM
Reply #315 has been edited for hoped for clarity.
Whoops. Is there a way to edit image caption? It should read "Z & S Common Bowlines".

Yes, edit it out, rename the picture and resubmit it.

SS
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 28, 2013, 10:57:28 PM

Well, it is still not clear to me... :)  I also do not understand the meaning of your mirror-symmetric triple-nipping-turn based Common bowlines...

Please answer this simple question. Do you understand that these mirror symmetric bowline's nipping turns exhibit opposite handedness? Both bowlines (in the photo I posted above) show Dan Lehman's preferred view. My point here is that the handedness per se of the nipping turn(s) does not redress all relations of the Working End's direction of entry into the nipping loop for all legitimate common and Eskimo bowlines. It makes no sense to me to eliminate - in your starting assumptions - half of the bowline population in order to solve (half) a problem. That's an inconvenient convenience. :) One more question, please. If this is you're intention, why bother. It seems to me all that would be accomplished is to provide another way of introducing more dyslexia inducing confusion into a world rife with such hazards.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 29, 2013, 03:56:07 AM
Let me try again..  :)

As I had explained earlier, I think that the path the orientation of which we should describe in the first place, is the path followed by the eye leg of the Tail side, as it enters into the nipping turn. When this path will be determined, the end / limb of the nipping turn which has to be encircled / collared by the continuation of this eye leg, and the path which has to be followed by the Tail when it will enter into the nipping turn, would be uniquely determined as well.

There are 4 distinct nipping turns, according to :

a.    The "over" / "under" mutual position of the two limbs of the nipping turn at its crossing point, i.e., if the Standing end goes "over" or "under" the eye leg of the Standing Part.  A convenient ( = Convenient ) way to represent a bowline is to show the 'Common" bowline tied on an over-then-under nipping turn, and the "Eskimo"  bowline tied on a under-then-over nipping turn. This way the crossing point of the bowline cannot be hidden underneath the legs of the collar
b.   The handedness of the helical structure of the nipping turn. The helical threads most widely used (= Common ) bolts and nuts are right-handed .

Let us imagine the nipping turn as a nut, and the working end as a bolt that enters into it.
Is there a unique relation between the handedness per se of the helix of the bolt and nut pair, and the kind of the bowline ( "Common" bowline or "Eskimo" bowline ) this working end can tie ?

1.   If we consider only the representations of the bowlines where :

a.   The "over" / "under" position is the Convenient.
b.   The handedness is the Common.

then we can see that :
The Common bowline is related to the right-handed helix ( the S helix).
Only a right-handed bolt / working end can tie a Conveniently represented Common bowline - and a Conveniently represented Common bowline can be tied only on a right- handed nut / nipping turn.

2.   If we consider only the representations of the bowlines where :

a.  The "over" / "under" position is the Convenient.
b.  The handedness is the opposite of the Common.

then we can see that :
The "Eskimo" bowline is related to the left-handed helix ( the Z helix).
Only a left-handed bolt / working end can tie a Conveniently represented "Eskimo" bowline, and a Conveniently represented "Eskimo" bowline can be tied only on a left-handed nut / nipping turn.
Therefore, I propose that the class in which the Common bowlines belong be labelled as "S-bowlines", and the class in which the "Eskimo" bowlines work be labelled as "Z-bowlines".

1. http://en.wikipedia.org/wiki/Right-hand_rule (http://en.wikipedia.org/wiki/Right-hand_rule)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 29, 2013, 04:35:51 AM
Reply #315 has been edited, hoping for clarity.
The " Z Common bowline", although it is Conveniently represented, indeed, clearly it can not be tied with a Common right-handed bolt / working end. The S bowline can be tied by a Common right-handed S bolt / working end that enters into a Common right-handed S nut / nipping turn - and the Z Eskimo bowline can be tied by a not-Common left-handed bolt / working end that enters into a not-Common left-handed Z nut / nipping turn.
I  believe that my re-written post, I had explained it with clarity.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 29, 2013, 05:03:35 AM
It makes no sense to me to eliminate - in your starting assumptions - half of the bowline population in order to solve (half) a problem. That's an inconvenient convenience. :)

I do not have to eliminate half of the bowline population - I have to eliminate the three quarters of it !  :)
First, from the 4 possible bowlines, I eliminate the ones in which the nut / nipping turn does not have the same handedness as the bolt / working end. So, from the 4 I go to 2. Then, I eliminate the ones that are not Conveniently represented. So from the 2  I go to the 1. I want a one-to-one correspondence / relation, and that is a convenient way to achieve this.
Remember, we only want to distinguish the Common from the Eskimo bowlines, with another label that uses a more "balanced" pair of terms than the bowline / anti-bowline one. We do not wish to classify the mirror-symmetric bowlines, as the two "Common" bowlines you show. In mirror symmetric knots the handedness is reversed, so there is no way one can retain a relation that includes handedness in it.
I do not say that all "Common" bowlines are right-handed, of course, I say that the "Common" bowline, in general, per se,  :) , is related to the S helix because of the fact that an eye leg of the Tail entering into an S nut / nipping turn as an S bolt, can only tie a "Common" bowline. By the same token, the "Eskimo" bowline, in general, per se, is related to the Z helix, because of the fact that an eye leg of the Tail entering into a Z nut / nipping turn as a Z bolt, can only tie an "Eskimo" bowline.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 29, 2013, 09:25:02 AM
Now this is much better than the bloated mess of your previous posts on this matter, and I can receive and accept it. You've anticipated some questions and responded in an informed and logical manner. So, yes, under those restrictive terms one can relate the common and Eskimo bowlines to specific handedness. While I concur with the unambiguous implications of your exclusive initial assumptions, I might not ascribe importance to those implications because of the restrictive nature required of the initial assumptions to arrive at them. Still, I can appreciate what you are trying to do here.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 29, 2013, 11:18:21 AM
Thank you alpineer,
It seems that writing and re-writing the same thing, consumes time of sleep, but it is useful after all !  :)
However, this experience also showed to me that people would probably jump to the ( obviously wrong ) conclusion, that all "Common" bowlines are right-handed, and all "Eskimo" bowlines are left-handed... The nut-and-bolt trick was meant to protect the reader from this misconception, by requiring the nut = nipping turn AND the bolt  = working end / eye leg of the Tail be BOTH S or BOTH Z. Perhaps a "SS" - "ZZ" labelling ?
I have also realized that people confuse the Convenient way or representing the bowline, with ONE particular side of the nipping turn, be it a right-handed or a left-handed. Let me emphasize this point :

The "Common" bowline is more conveniently represented when tied in a nipping turn where the Standing Part goes "over" the eye leg of the Standing Part, be it a right-handed or a left-handed one. This way the crossing point area of the nipping turn is not hidden underneath the two legs of the bight component. Similarly, the "Eskimo" bowline is more conveniently represented when tied on a nipping where the Standing part goes "Under" the eye leg of the Standing Part, be it a right-handed or a left-handed one. We should reverse the "over" / "under" way  the Standing part meets the eye leg of the Standing part at the crossing point of the nipping turn, in order to achieve for the "Eskimo" bowline the same thing we seek for the "Common" bowline : an as less as possible hindered by the two legs of the collar view / aspect of the nipping turn - which nipping turn in the most important of the two components of every bowline, the other one being the bight component / collar.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 30, 2013, 05:31:09 AM
Thank you alpineer,
It seems that writing and re-writing the same thing, ...
EsPECiALly if it's this stuPid
" the eye leg of the Standing Part",
nomenclature --which I'll hope has been wrung out of
Agent_Smith's pen, lest it find itself against a mightier
sword!

Quote
Similarly, the "Eskimo" bowline is more conveniently represented
when tied on a nipping where the Standing part goes "Under"
...
AND one of the great benefits or frustrations,
depending on how bent one is on these matters
(I feel the pain),
is that with the "Janus" forms in which "one good
collaring deserves another" cover both halves of
the argument and so are equally half-full/-empty
no matter!
= a tie.
Heck, yeah, a darn good tie(-on)!

;D
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alpineer on July 30, 2013, 08:05:34 AM
"eye leg of the Standing Part" is improper syntax as it implies that the eye leg is part of the S.Part
"Standing Part Side eye leg" is proper syntax as it implies that the eye leg has an association of proximity to the S.Part
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 30, 2013, 10:31:14 AM
"eye leg of the Standing Part" is improper syntax as it implies that the eye leg is part of the S.Part.

Is nt it ? To my view, anything ante the tip of the ey , is Standing Part... Anything we can form a second, or third, etc. nipping turn on, and pass the eye leg of the Tail through it, after we pass it through the main nipping turn, belongs to the Standing part.
I will follow whatever agent_smith decides - because we should have a common ground to understand each other, and the "Analysis...." offers such an opportunity...The next one may well come after 60 years. Will I live till then ? I doubt it... :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 30, 2013, 04:07:09 PM
you are washing your hands by pointing to agent_smith
I am not "washing hands", I have my own opinions and I express them whenever I can, as my tons of blahing blahing in this Forum prove -- so, evidently,  I am not afraid to do this !   :)  I wonder how one can think I am the kind of person that is not willing to bear the consequences of expressing what he believes, by hiding himself behind others !
My own collection of bowlines, my terminology and my views of how they work, were and still are not the same as agent-smith s - but I have no problem to follow his choices, or anybody else s choices, for the sake of finding a common ground, when I am convinced they are about as near the truth as mine s.
The " Analysis ..." is published for 4 years now. I do not think they have established any de facto standard - regarding knots, in general, and bowlines, in particular, we are still living in the Tower of Babel ! I do not see much consensus on much things, I do not even see many people that have studied the previous versions...What makes you think that they are gong to swallow the present one, without any criticism ?
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: X1 on July 30, 2013, 05:01:39 PM
It is not even like this !  :)  It is "eye leg of the Standing part s side", and the "eye leg of the Tail side " ...
However, I have not seen any better alternative, so, for the time being, we are left with this. Imagine that I write this looong phrase each and every time I am writing about bowlines - and I have to admit that I write about bowlines a lot !  :)  Place your bets / faites votre jeu..
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on July 30, 2013, 06:51:56 PM
It is not even like this !  :)  It is "eye leg of the Standing part s side", and the "eye leg of the Tail side " ...
However, I have not seen any better alternative, ...

But you have, and it has been explained.
The focus of the language is on the eye and on
Which side/leg, therefore the proper grammar is
to refer to the eye and qualify that noun.
Agent_Smith's terminology is bassackwards, referring
to either SPart or Tail and modifying IT to denote part
of the eye.  How clumsy can you get?  Well, that's too
harsh : this challenged terminology can be seen as
"nub"-centric, looking out from where there is a SPart
& tail into the eye.  But, practically, I think we're best
oriented upon the eye and then qualifying; after all,
the eye here is a key element, joining human to safety!

Improvement might be seen, in actual diction, using
"tail" & "through" as modifiers : the SPart side is the
latter, as forces --and indefinite distance-- run "through"
the nub, in contrast to that on the tail's side, where
there is the end of things.  (Woe be unto us and the
mid-line eyeknots, "with no end in sight"!)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: xarax on March 25, 2014, 09:50:46 AM
Recently, Alan Lee has tied some fine, secure bowline-like PET eyeknots where either the first (1) or the second (2) leg of the collar do not penetrate the nipping loop ! ( The only instance I have seen something remotely resembling this, but not so radical, is at the Fontus bowline (3) : a Janus-like bowline where the Tail End does not penetrate the nipping loop - but, regarding the first or the second leg of the collar, I had never questioned the need to go through the nipping loop...). The problem arises instantly : Should they be considered / defined as bowlines, or not ?
I have to admit that I have been tying "ordinary" bowlines for too long, during most of my life, so I can not judge this matter objectively. I still find it "difficult", mentally, to tie those loops without looking at their pictures, although I have tied them many times till now. That is, I have been brain-washed by the "working end going through the nipping loop before and after the collar" pattern, and, being an old dog, I can not really learn the new trick... Younger and fresher knot tyers would perhaps be more able to have a say on this matter.

1. http://igkt.net/sm/index.php?topic=4125.msg31307#msg31307
2. http://igkt.net/sm/index.php?topic=4125.msg31273#msg31273
3. http://igkt.net/sm/index.php?topic=1202.msg19317#msg19317
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on February 15, 2016, 09:15:55 AM
The Capstan Effect:

Does it exist and is it measurable?
Can a test rig be devised which can reliably and consistently detect it? And if so, could others repeat the experiment to verify it?

The test rigs I have used thus far have not revealed a capstan effect in a standard #1010 Bowline.

While toying with some ideas - it occurred to me that perhaps it may be possible to detect a capstan effect in #1431 Sheet bend.

In advancing my Analysis of Bowlines paper, I have posited that there is no nipping loop in a Sheet bend because it is not loaded at both ends. The compressive force of the nipping loop in a standard #1010 Bowline effectively grips and crushes both legs of the bight - removing any detectable capstan effect.

But the core of a Sheet bend should not produce the same compressive force as a Bowline because only the SPart is loaded. And therefore I surmise that it might be possible to detect a capstan effect. A few quick tests by hand did indicate some promise...

If a capstan effect can be demonstrated in #1431 Sheet bend - this would provide strong evidence that the core function of a Sheet bend does not produce the same level of compressive force as a nipping loop in a Bowline. And this in turn would support the definition that a nipping loop must be loaded at both ends.

Mark G

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on February 18, 2016, 05:47:47 PM
The Capstan Effect:

Does it exist and is it measurable?
Can a test rig be devised which can reliably and consistently detect it? And if so, could others repeat the experiment to verify it?

Mark G

The capstan effect is real and it is an absolutely critical part of knot operation.  For example, in #1010, the capstan effect is responsible for transmitting SPart load into the bight legs and thus into the 'return' loop leg.

The capstan effect is present and active every time one cord passes around another and has a loading differential one end to the other.  This includes the situation found in the Sheetbend where one end of the turn is loaded and the other is simply clamped.

However, no capstan effect is generated when neither end is loaded or when both ends are loaded equally.

I believe this issue though, came about over the suggestion that the Bight collar in #1010 expresses a capstan effect, and this helps prevent the WE from being pulled through the nipping helix.

The simplest test rig we can set up to demonstrate the presence or absence of this effect in the working (i.e. loaded) is shown in this image made by Mark.

(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20421;image)

If there was any capstan load shedding around the SPart, then one of the legs would be more loaded (and therefore straighter) than the other.  We can see clearly from this image that neither of the legs are loaded, and so it is impossible for there to be any capstan load shedding in this part of the knot.

This situation however, does not hold true for extreemly low CF cordage.  In very strong, low CF cord, some of the load on the loop can escape the grip from the nipping helix and progress into the collar area, where, because the WE is clamped, it can start to set up a slight capstan load shed around the SPart.  However, because of the low CF and the presence of only one and a half radians of turn, only an insignificant capstan load shedding force is generated.

Of far greater significance however, is the negative cogging present in the legs of the bight component.  It is generally presumed that there is no load on the WE.  In reality the negative cogging is able to transfer load from the outgoing loop leg into the WE, essentially generating an effective WE load and contributing towards overall knot function and stabilisation.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on February 18, 2016, 08:08:00 PM
The Capstan Effect:
...
But the core of a Sheet bend should not produce the same compressive force
as a Bowline because only the SPart is loaded.  And therefore I surmise that it
might be possible to detect a capstan effect. A few quick tests by hand did indicate some promise...

If a capstan effect can be demonstrated in #1431 Sheet bend - this would provide strong evidence that the core function of a Sheet bend does not produce the same level of compressive force as a nipping loop in a Bowline. And this in turn would support the definition that a nipping loop must be loaded at both ends.
Why are you reaching so desperately for something here
re the alleged "capstan effect"?!  I don't see great promise
for this pursuit, esp. vis-a-vis the bowline.

As you note, the end-2-end knot differs significantly,
but you've only remarked about one side/end's
difference : the bight's side differs in that what would
be the "returning eye leg" bears full load in the
end-2-end knot, not in the eye knot; so there is not
only less nipping as you suggest, but more need.
That the end-2-end knot has been reported to slip
in some kernmantle ropes (the Dave Richards report,
once hosted by NSS but removed for silly reasons)
only goes to confirm these differences.

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on February 18, 2016, 08:21:19 PM
I believe this issue though, came about over the suggestion that the Bight collar in #1010
expresses a capstan effect, and this helps prevent the WE from being pulled through the nipping helix.

The simplest test rig we can set up to demonstrate the presence or absence of this effect
in the working (i.e. loaded) is shown in this image made by Mark.
//
If there was any capstan load shedding around the SPart, then one of the legs would be
more loaded (and therefore straighter) than the other.  We can see clearly from this image
that neither of the legs are loaded, and so it is impossible for there to be any capstan load
shedding in this part of the knot.
I disagree that this image proves anything, much.  As I've
previously said --in another thread?--, this image shows
so much bending of the collar's legs that one can suggest
a capstan effect at this point / in the turNip, nevermind
needing anything further, at the bight's head/collar!
And I surmise that the situation is different where the collar
is reasonably sized much smaller and the bight legs more
nearly aligned with the axis of tension.  And it might be
that one could load and measure --somehow-- tensions
of either side of the collar (or maybe observe slight slippage
of the returning eye leg into the eye?) which would give
weak support to the alleged effect.

But I think that the alleged effect is being exaggerated
in significance.  It seems to consume a great deal of the
latest draft of the Bowlines document, to no benefit and
much diminution of the overall presentation, IMO.

Meanwhile, Derek has raised a valid point about how the
central nipping turn can be stabilized w/o a collar, and in
that point I've indicated one knot (which came by his
recipe though his verbal description ran off incomprehen-
ably to me), and which has other knots to rely on such
non-bight stabilization, too.  --where the opening of the
nipping loop="tightest helix" requires the bending of
nipped parts anchored on one side, and esp. in firm cordage
will work with good stabilization, I think.

As for calling the loops through & around the nipping loop
a "collar", I'm thinking "no, they're not" --or what would
NOT be, if they are?!  Yes, they do stabilize, but ... !?

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Stalker on March 18, 2017, 07:18:25 PM
I have to go with what DerekSMith said. One of the fundamental aspects of a bowline is the inclusion of a Sheet bend.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on March 23, 2017, 02:07:32 AM
Quote
I have to go with what DerekSMith said. One of the fundamental aspects of a bowline is the inclusion of a Sheet bend.

That makes absolutely no sense.

A sheet bend is an 'end-to-end joining knot'.  It is not an 'eye knot'.

By definition, a Bowline is an 'eye knot' - because it has a connective interface (the 'eye') - which enables the Bowline to attach to something (eg a carabiner, or to a climbing harness).

I think what you meant to say is that Bowlines have a SB core (meaning that there is a 'bight' segment and a 'nipping loop' segment...although in the case of a Sheet Bend, the nipping loop is 'partially formed'). This is the basis of Derek Smith's position.
I have difficulties with the SB core theory...because some Bowline structures dont quite fit this definition. An example is the 'Lee Zep Bowline' and #1033 'Carrick Loop' (per Ashleys naming). Both of these structures have a 'nipping loop' as a key mechanism and they are both 'eye knots' that are jam resistant. I view both these structures as 'Bowlines'. The central nipping loop as a key mechanism that all Bowlines share is a theory that does seem to work - while the SB core theory is too narrow and does not apply to some structures.

In my personal view, there is no functional nipping 'loop' in a Sheet Bend. And the Sheet Bend is not an eye knot.

And this comes back to what is the definition of a 'loop' (and indeed...what is a 'nipping loop'). I had required that the nipping loop must be loaded at both ends in order to qualify. In a Sheet Bend - the nipping structure is not loaded at both ends...and so it is not a 'nipping loop'.

In my paper - I have advanced the theory that all Bowlines have a 'nipping loop' as a key mechanism. This of course was a concept originally advanced by Dan Lehman - which I concur with.

Other features which all Bowlines share include; a connective 'eye' (giving rise to the term 'eye knot' - because the 'eye' enables connections to be made), resistance to jamming, and 'PET'.

Many of these concepts were independently advanced by Dan Lehman, Xarax, and a host of other IGKT members over a very long period of time.

Mark Gommers
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot rigger on March 25, 2017, 09:39:25 PM
Quote
In a Sheet Bend - the nipping structure is not loaded at both ends...and so it is not a 'nipping loop'.

How about a double sheet bend?  Does it have a nipping "loop"?

How about a sheet bend as a netting knot (aka weaver's bend)?  The nipping "loop" is loaded on both ends in that case?

cheers
andy
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knotsaver on March 25, 2017, 11:57:48 PM
Quote
In a Sheet Bend - the nipping structure is not loaded at both ends...and so it is not a 'nipping loop'.

How about a double sheet bend?  Does it have a nipping "loop"?

Hi Andy,
to my mind it does not! the end isn't loaded, we could say that it is locked.
Please notice that another difference  in the Sheet Bend is that the Standing Part of the U turn is 100% loaded,  whilst in a Bowline it is 50% loaded (Edit: roughly speaking, I think it is not so simple to understand how the load is shared between the two eye-legs in a real case, it depends on the angle between the eye-legs too: the extreme case is the ring loading)

Quote from: knot rigger
How about a sheet bend as a netting knot (aka weaver's bend)?  The nipping "loop" is loaded on both ends in that case?

In that case I think we shouldn't call it a Sheet Bend , it isn't a Sheet Bend...

Ciao,
s.
p.s. @Mark happy to "read" you again  :)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on March 27, 2017, 11:22:51 PM
Quote
In a Sheet Bend - the nipping structure is not loaded at both ends...and so it is not a 'nipping loop'.

How about a double sheet bend?  Does it have a nipping "loop"?

Hi Andy,
to my mind it does not! the end isn't loaded, we could say that it is locked.
Please notice that another difference  in the Sheet Bend is that the Standing Part of the U turn is 100% loaded,  whilst in a Bowline it is 50% loaded (Edit: roughly speaking, I think it is not so simple to understand how the load is shared between the two eye-legs in a real case, it depends on the angle between the eye-legs too: the extreme case is the ring loading)

It gets tricky to base definitions upon physical characteristics,

E.g., I've fiddled what I regard as *bowines* where the U-part
doesn't lead to the eye, or where the continuation of the turNip
runs not into the eye but into a collar around the eye legs
(and so might be seen to not really be loaded).

And what of the multi-eye bowlines?  If load is distributed evenly
over alllll of those eye legs, that one leading back to the "Is it a
nipping loop?" part must have only a fraction of the load, right?!
How much is enuff?

Knotty nuances!

;)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on March 28, 2017, 02:27:28 AM
Quote
It gets tricky to base definitions upon physical characteristics,

Tricky yes - but we can say the same thing with many areas of science and physics (particularly quantum physics). But this by itself should not deter humans from seeking to understand and describe and measure the physical world.

I am surprised that you did not speculate about ABoK #1117 (The running Bowline noose).
This is a structure that is worth examining to see if it deserving of having the title 'Bowline' in its name.

What is #1117?
Certainly, it is a 'noose'.

Can it be described as a 'Bowline'?

Strictly speaking - it is not an eye knot (it is a noose). Bowlines are understood to be 'eye knots'. In a classical sense, Bowlines have a fixed 'eye'...however some have a communicating segment which contradicts the notion of 'fixed'.
#1117 does not have a 'communicating' segment as does #1083 and #1087 (see below).
Perhaps it is a composite Bowline noose?
I would be interested to learn of your thoughts here...

I used #1117 as a follow up to your contention re 'nipping loops' (for which you still seem to prefer to use the term 'turNip').
In #1117, the 'nipping loop' would still be functional when the noose structure is loaded and cinches up tight against an object.

Quote
And what of the multi-eye bowlines?  If load is distributed evenly
over alllll of those eye legs, that one leading back to the "Is it a
nipping loop?" part must have only a fraction of the load, right?!
How much is enuff?

And some examples include: (list is not exhaustive)
[ ] #1083 (Double Bowline on the bight) - this structure has a functional 'nipping loop'
[ ] #1087 (Spanish Bowline) - this structure has 2 functional 'nipping loops'
[ ] #1088 (Sheepshank knot with Half hitches) - interesting structure - does it have a functioning 'nipping loop'? Yes - it has 2. But, the mere presence of a 'nipping loop' does not by itself qualify the structure as being deserving of the title 'Bowline'.

In #1088, there are 2 nipping loops - but, it has no collar. The collar is a key element of a Bowline.
And all Bowlines are 'eye knots' - but it gets murky here because in all three cases - the eyes have a 'communicating' segment...and so the 'eyes' are not of a fixed dimension.

Ashley correctly identified #1083 and #1087 as 'Bowlines' - because both structures have a collar and a nipping loop (but the eyes are not fixed).

#1088 fails to be a 'Bowline' on account that it has no collar .

Quote
"How much is enuff?"
(per Dan Lehman in relation to the definition of a 'nipping loop')
The answer would seem to be any load - provided that there is load at both ends of the 'nipping loop'.
So this means zero load at one or both ends would disqualify a structure from being a 'nipping loop'.
And this is why a Sheet Bend has no 'nipping loop' - because only one end is loaded.

Summary:

Bowlines must have the following elements present:
1. A collar
2. A nipping loop (there may also be nipping loops)
3. An 'eye' (or more than one eye) - and the eye structure may have a communicating segment, in that it does not have to be of a fixed dimension.
A further quality of Bowlines is that they are jam resistant.
And a further quality is 'PET' (post eye tiable) - although not all Bowlines are PET for attachment to an object such as a climbing harness - so PET is not an absolute requirement.

Mark Gommers

EDITED for clarity and to properly respond to Dan Lehman's questions...
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on March 29, 2017, 01:55:34 AM
I am surprised that you did not speculate about ABoK #1117 (The running Bowline noose).
This is a structure that is worth examining to see if it deserving of having the title 'Bowline' in its name.
What is #1117?
Deserving that, yes, but it's not a *knot* IMO,
but a knotted structure (the knot part being #1010).

Quote
Certainly, it is a 'noose'.
Okay, but a noose isn't a *knot*, but a structure.
(And put 2 half-hitches in this group --where the knot
is a clove hitch in this *noose* structure.)

Quote
[ ] #1088 (Sheepshank knot with Half hitches) - interesting structure -
QUITE !!  Where I have mused about ignoring the eye
of a bowline --and focused on a "cookie-cutter" knotted
part, solely, and of what of the 4 ends (parts exiting this cutter)
are loaded--, how then ... the sheepshank, for IT's center
strands run w/o definite length between knotted parts (two, as
you note), and aren't really a part thereof (knotted, i.e.).
QUITE a challenge.  (And the would-be "collar" bight is just
out in the air, indefinitely sized, too!?)

While we're at it, the twin bowlines structure asks YOU if
it is a *bowline* (if it has an "eye"), and us if it is a *knot*;
its knotted parts are more engaged than above, but are still
plural, separated, and ... !?  (And in neither the "twin..."
end-2-end structures nor the sheepshanks need the two
knotted parts (oh, yes, there can even be more than two
--center stuff for decoration/fascination!) be the same.

Quote
The collar is a key element of a Bowline.
Aha, Xarax lives!

Many of MY *bowlines* do w/o a collar and all seem happy at that.  ;D

Quote
And all Bowlines are 'eye knots'
Unless I go on with the cookie-cutter *knot* idea,
which would focus solely on the entangled/knotted part.
Maybe "solely" is too strong?  --but it seemed so pure!

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot rigger on March 29, 2017, 04:28:20 AM
Quote
Quote
"How much is enuff?"
(per Dan Lehman in relation to the definition of a 'nipping loop')
The answer would seem to be any load - provided that there is load at both ends of the 'nipping loop'.
So this means zero load at one or both ends would disqualify a structure from being a 'nipping loop'.

I find this notion of definition based on loading pattern to be problematic.

Imagine a Round Turn Bowline (https://tinyurl.com/lrujzxs (https://tinyurl.com/lrujzxs)) tied around a sizable tree branch to suspend a child's swing.  Assuming sufficient friction between the tree bark and round turn, when the swing pendulums, a leg of the eye will slack.  Given the "loading" definition paradigm proposed, when the child swings the knot will transform from Sheet Bend, to Bowline, to Lapp Bend.

I propose that this result is at odds with common sense.

Another example would be that of a Long Tail Bowline, where the working end of a standard Bowline (ABoK#1010) or Outside Bowline (ABoK #1034 1/2) is intentionally left extremely long, for the purpose of being loaded (usually in a rope rescue application).  If their is load solely on the long tail of the bowline (ie working end) and not the loop eye, does the knot cease to be a bowline?  And if the loop were loaded again it would again become a bowline?

Taking this logic an absurd step further, would a standard (#1010) bowline tyed, dressed and set, but unloaded (ie standing end, and eye both slack) would it not be a bowline? Does it become a Bowline only when taut?

In general I mostly agree with Agent_Smith's summary:
Quote
Bowlines must have the following elements present:
1. A collar
2. A nipping loop (there may also be nipping loops)
3. An 'eye' (or more than one eye)

I'm not quite sold on some aspects of it, particularly that a nipping loop must be loaded on each end.
My own (current) conclusion is an unloaded Bowline is still a Bowline.

Quote
Quote from: knot rigger
How about a sheet bend as a netting knot (aka weaver's bend)?  The nipping "loop" is loaded on both ends in that case?

In that case I think we shouldn't call it a Sheet Bend , it isn't a Sheet Bend...

knotsaver; names of knots are based on common usage IMO, (see ABoK #952)  If a certain knot, in a certain application, that has been called by a certain name for hundreds of years, doesn't fit a proposed definition, I find it more reasonable to modify the definition rather than changing the name of the knot!

One last note,  I came across this topical article:

How Many Bowlines? by Glen A. Dickey in Knotting Matters issue 87
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on March 30, 2017, 03:17:25 AM
Quote
I'm not quite sold on some aspects of it, particularly that a nipping loop must be loaded on each end.
My own (current) conclusion is an unloaded Bowline is still a Bowline.
Per knot rigger...

I think there is a fundamental misunderstanding here...possibly caused by language.
Obviously, an unloaded Bowline is still a Bowline!

The absence of load is not the issue.

Going back to #1431 (Sheet bend) as an example - I posit that there is no functional 'nipping loop' in this structure.
The unloaded state does not change the fact that it is a Sheet bend
When load is applied, we can see that the nipping structure will have load at one end only (and so it can't be defined as a 'nipping loop').
The point is, a loaded or unloaded state does not change its identity as a Sheet bend.

If I tie a common #1010 Bowline and hold it loose in my hand - obviously there is no load.
However, in the loaded state - we can see that the nipping structure experiences load at both ends - and therefore it can be described as a 'nipping loop'.

Mark
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knotsaver on March 30, 2017, 03:21:15 PM
Quote
I'm not quite sold on some aspects of it, particularly that a nipping loop must be loaded on each end.
My own (current) conclusion is an unloaded Bowline is still a Bowline.
Per knot rigger...

I think there is a fundamental misunderstanding here...possibly caused by language.
Obviously, an unloaded Bowline is still a Bowline!

The absence of load is not the issue.

We are mixing two "layers": the static and the dynamic one and this often creates a misunderstanding, but we  have to be able to distinguish the nub of a Sheet Bend from the nub of a Bowline. I like the concept of a functional "nipping loop" and I think that it is fundamental in the  characterization of a Bowline.
Why do we have to say
One of the fundamental aspects of a bowline is the inclusion of a Sheet bend.
?
and why don't we say: one of the fundamental aspect of a Sheet Bend is the inclusion of a broken Bowline?
I think because they work differently...
Perhaps the Sheet Bend was tied before the Bowline, perhaps the first one was the Becket Hitch (who knows? does anyone know it?) but I think we have to distinguish one from another.

.
And a further quality is 'PET' (post eye tiable) - although not all Bowlines are PET for attachment to an object such as a climbing harness - so PET is not an absolute requirement.

About PETness (I agree with Xarax) I think it should be an absolute requirement...

knotsaver; names of knots are based on common usage IMO, (see ABoK #952)  If a certain knot, in a certain application, that has been called by a certain name for hundreds of years, doesn't fit a proposed definition, I find it more reasonable to modify the definition rather than changing the name of the knot!

hm? I exaggerated :) but we shouldn't name it a Sheet Bend. ;)
ABoK #952???  :-\
for the name? ah ok so we can't name a netting knot  "Sheet Bend" ;) :) (Ashley named it Mesh Knot #402 but he said...(he said: "is the ordinary way of tying the Sheet Bend when it is made with a netting needle."))

One last note,  I came across this topical article:

How Many Bowlines? by Glen A. Dickey in Knotting Matters issue 87

I think it does not help us in our attempt to define a Bowline...however it is interesting.

Ciao,
s.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on March 31, 2017, 02:37:24 AM
Quote
Quote

The collar is a key element of a Bowline.

Aha, Xarax lives!

Many of MY *bowlines* do w/o a collar and all seem happy at that.

Yes...Xarax lives!
I agree with him that a key element of all 'Bowlines' is the collar.
And I'd like to see some clear photos of these alleged 'Bowlines'!

The collar is not the only element though...because a 'nipping loop' also must be present.
And the 'nipping loop' must be in the form of a loop - the definition of a loop was defined elsewhere on this forum (in contrast to a turn or some other maneuver that doesn't qualify as a loop).
And this loop must be loaded at both ends (the amount of load is not defined, but it does not have to be in equal proportions).

And Bowlines are 'eye knots' (not bends or hitches)....although the 'eye' does not need to be of a fixed dimension.
Bowlines are also jam resistant and 'PET' (although 'PET' may be conditional).
NOTE: With regard to 'PET' - not all Bowlines are PET when attached to objects such as a climbing harness. For example, #1080 (Bowline on a bight) cannot be attached to a climbers harness via the TIB method (although in theory, a gigantic bight of rope could be passed over ones head and body to step through...but that would not be practicable and in fact would be silly to attempt). Mind you, a work-around would be to avoid the TIB method altogether and re-thread the entire knot to recreate it via single strand - but this is cumbersome. So the requirement for 'PET' can be problematic.
I am not convinced that PET is an absolute requirement for an eye knot to be awarded the title of 'Bowline' (although it certainly is an attractive proposition).

...

Curiously, Ashley referred to #1057 (single Bowline on the bight) and #1058 (single Bowline on the bight) as 'Bowlines'
I disagree, and the term 'Bowline' should not have been used in the title.
I see no functional 'nipping loop' in either of these structures - which automatically disqualifies them from being Bowlines.

Mark G
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on March 31, 2017, 08:01:58 PM
And I'd like to see some clear photos of these alleged 'Bowlines'!
The Myrtle is just such a knot,
and coming in from the opposite side of the
nipping loop with the returning eye leg one
should re-insert (closing this eye-leg loop)
on the eye-side (vs. SPart-side as done w/Myrtle)
for surer holding.  (Make a double turn, and it matters
less!)

Quote
Bowlines are also jam resistant and 'PET' (although 'PET' may be conditional).
NOTE: With regard to 'PET' - not all Bowlines are PET when attached to objects such as a climbing harness.
Worse misspelling than 'prussic' even, this 'PET' vice 'TIB' !!

Not all of my *bowlines* are PET or TIB (some are),
but the PET ones by definition are thus when attached
--to ANYthing!

Quote
For example, #1080 (Bowline on a bight) cannot be attached to a climbers harness via the TIB method (although in theory, a gigantic bight of rope could be passed over ones head and body to step through...but that would not be practicable and in fact would be silly to attempt).
Ha, somewhere I just saw this very process promoted,
for a middle-man tie-in!  (In the case of some accident,
fall, tension ..., it makes getting free of the rope a real
challenge, alas.)

Quote
Mind you, a work-around would be to avoid the TIB method altogether and re-thread the entire knot to recreate it via single strand - but this is cumbersome.
It is also recommended, by DAV (German climbing) and
maybe some others.  In general, tie-in knots that entail
making a 2nd pass for a 2nd eye will prove to be more
overall-secure vs. complete loosening than others.

As for the assertion
"a <whatever eye knot or end-2-end knot or hitch> UNloaded
is still that knot,
I beg to differ.  Certainly, my direction points to awkward
*speaking*, but at least for the purpose of some formal
knotting discussion, it could well be that one would consider
things.  And there is some practical side in cases where the
particular loaded_*knot* just falls apart absent tension
(and so would be hard to posit as "STILL being..." --just *being*!).

My e.g. of "bowline" (and other eye knots) considered at the
"cookie cutter" view (all *ends* exit the cutter perimeter w/o
specific connection)
is of a barge pulled with a tow line tied to starboard cleat
and the barge's shorter like line tied to port cleat and then
joined to the tow line in a --well, what do you call it(?),
"bowline" :: any knotter given the cookie-cutter view
of just the entangled/knotted part and its ends' tensions
or not would immediately recognize it as such,
irrespective of the barge *interrupting --or completing?--*
the "eye" bight.
(Take this example but change angles to 120deg all 'round,
and then what?  --bit more change to put >120deg on both
sides of the short line (barge port cleat) and you then see

.:.  It comes down to how you want to speak, how you
want to regard entities, what purpose you address.  In
common parlance, yes, you don't want to have knots
acceptably be openly spoken of as transforming an eye knot
into an end-2-end knot (wrong bowline into right Lapp bend).

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knot rigger on March 31, 2017, 08:54:25 PM
"It is hardly necessary to name a knot, but it assists materially in finding it a second time if the occasion arises."

From ABoK #952

Part of what I read from Ashley's remark is that a name of a knot is only a convenient way to talk about it with another not tyer. "Bowline" and "Sheet bend" knots both derive their names from the the particular line on a ship with which one would tye these knots.  Saying "tye the knot that I taught you to attach the line that runs from the front of the boat up to the sail" isn't quite as efficient as saying "tye the knot used in the bow line", or even more simply "tye a bowline".  To state the obvious: the name (or classification) is just a convenient description of an idea.

Agent Smith:

Perhaps we are two not tyers separated by a common language.  The point I was trying to make in my earlier post wasn't simply a semantic discussion of "load" or "taut" and "slack".  It is, of course, absurd (as I mentioned) to propose that an unloaded bowline isn't a "bowline".  I will attempt to state my point more directly (while trying to be brief).

I assert that the conclusions of the proposed bowline definition scheme should be judged against common sense.  Should the implication of the definition paradigm be non-nonsensical, then the definition isn't clear and ought to be modified. (or perhaps it's the best we got and we should all stop discussing it, but what's the fun in that)

How should one judge "common sense?" I'm quite certain I don't have the definitive answer for that! But I propose that handing a "bowline" to be judged to a fellow worker of knots (sailor, arborist, climber, rigger etc) and ask him what it is:  If he says something like "that looks like a bowline" I would suggest it passes the "common sense" test.

If a knot can be tyed that passes the "I know it when I see it" bowline test, but fails to meet the (proposed) definition, it would mean (to me) that the definition is inadequate, incomplete, or ill-conceived.

Quote
Bowlines must have the following elements present:
1. A collar
2. A nipping loop which requires both ends to be loaded
3. An 'eye'
as per Agent_Smith, edited for clarity with my words in italics

In my earlier example of a Long Tail Bowline (ABoK #1034 1/2) which has the (admittedly unusual, but not unrealistic) loading profile that the standing and working ends be loaded, but the loop not taking any load.  By the common sense test, this is clearly a "Bowline", but it doesn't meet the "nipping loop must have both ends loaded" rule of the definition.

Now if you were to load the loop, then it would fit the definition.  As with the child's swing example I cited, the knot changing classification, or "what it is," based solely on how it's used and loaded is a concept that I intuitively find illogical.  I propose the following maxim:

"The dang-ol' knot I tyed can't change what it is after I tied the f*cker" :D

I do hope that my comments be taken as constructive, as I've intended them, and not merely contrary.

cheers
andy
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on April 01, 2017, 05:57:11 AM
Dan, I think you have split a sentence of mine into 2 parts - which alters the meaning...and then you critiqued the broken meaning.
The second part of my sentence had to be read with the first - otherwise the meaning is lost.

#1080 (Bowline on a Bight) is most easily tied via the 'TIB' method (tied-in-the-bight...or.. tying in the bight)...at least that is the ordinary intent.
My point was that trying to form an attachment with #1080 to a climbing harness via the TIB method is problematic. I stated that is COULD be done - but, it would be a ludicrous process. In that sense, #1080 is not readily 'PET' to a climbers harness via the TIB method. It was in that context that I said the requirement of 'PET' might be problematic. I am not 100% sure if 'PET' is an absolute requirement for all Bowlines! I think this needs to be given more thought...
There is a lot of jargon here and acronyms abound...its getting to be a bit of a mouthful.

Dan, the 'Myrtle' (in my view) does have a collar. And what of #1033 (Carrick loop)? Does this have a collar? Again I say yes!
I thought this matter had been debated endlessly and resolved?
Based on this - it appears that the definition of a 'collar' and its importance in a Bowline needs to re-opened?
What are your comments re the role of a 'collar' in a Bowline?
NOTE: And yes, you may well jokingly make remarks about Xarax... :) but, I think he deserves a lot of respect on account of the many contributions he made in this IGKT forum. He broke a lot of new ground and introduced many interesting new ideas and ways of thinking about knots. He did provide sound reasoning in support of the collar and its role in a Bowline. Please don't summarily dismiss Xarax!

I concur with you re the role of the 'nipping loop' in all Bowlines. But I also concur with Xarax with the role of the collar!
Can both elements co-exist in a nice harmony?

...

knot rigger: I concur with most of what you write.
However, the commonsense test may not be entirely valid, nor indeed a foolproof test. I prefer the 'scientific method' - although it is tough to apply in the field of knotting. There must be a way to quantify this body of knowledge into a theory of everything!!

Look at #1033 (Carrick Loop) and Alan Lee's 'Lee Zep Bowline', and indeed the base ''Myrtle'.
These structures might not pass the 'commonsense' test - and this may be due to the perceived difficulty with identifying a 'collar'. For instance, are parallel legs an absolute requirement for a structure to be deemed a 'collar'?

Dan Lehman has posited that the fundamental essence of a Bowline is a 'nipping turn'.
Ashley never stated this - and as far as I can see - no other knot author (even Budworth) has stated such.
I agree with Dan - the 'nipping loop' is a key element - the absence of which automatically rules out a knot from being a Bowline.

What I have tried to do is take this one step further - and to fully define what we mean by 'nipping loop'.
I think we both agree that loaded or unloaded - the identity of a Bowline remains unchanged.
So its just a case of getting the language correct in defining what we mean by 'nipping loop'.
Quote
A nipping loop which requires both ends to be loaded
per knot rigger
This is a definition worthy of consideration...
Or
[ ] 'Nipping loop' - tension force will be present at both ends in the loaded state. The tension force is not required to be in equal proportion.
If load is not capable of producing a tension force at both ends - this disqualifies the structure from being a 'nipping loop'. An example of such is #1431 (Sheet Bend).

Mark G
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knotsaver on April 01, 2017, 03:24:50 PM
let's consider an easy (?!) case...
(to be continued...)
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knotsaver on April 01, 2017, 03:52:23 PM
<
http://igkt.net/sm/index.php?topic=3233.msg39594#msg39594
>
...

Re(-re)ading the old articles, I'm reminded of another point:
the **nub** matches that of angler's/perfection loop (#1017)
but one's ends are the other's eye legs (!).
( http://igkt.net/sm/index.php?topic=4480.msg38577#msg38577 )

Please look at the attached picture.
Same nub but different behaviour.
The Angler Loop is a nice eye, it is TIB, it is not PET, it is difficult to untie.
The (Lehman (Sorry Dan I continue to name it Lehman)) Locked Bowline is a secured Bowline, it is TIB, it is PET, it is easy to untie.
Does the PET quality of an eye imply easiness of untying it?

Worse misspelling than 'prussic' even, this 'PET' vice 'TIB' !!

Not all of my *bowlines* are PET or TIB (some are),
but the PET ones by definition are thus when attached
--to ANYthing!

Why do you say that, Dan?
Am I missing something?

Ciao,
s.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on April 01, 2017, 04:19:30 PM
Please look at the attached picture.
Same nub but different behaviour.
The Angler Loop is a nice eye, it is TIB, it is not PET,
it is difficult to untie.
The (Lehman (Sorry Dan I continue to name it Lehman)) Locked Bowline is a secured Bowline,
it is TIB, it is PET, it is easy to untie.
Does the PET quality of an eye imply easiness of untying it?
No.
And "easy to untie" is a YMMV per materials, forces, & needs
--i.e., maybe the need is likely to be able to do so, possibly
w/help of tools.  I saw this knot (perfection/anglers loop once
in some commercial-fishing/-marine cordage lying about,
and it appeared that the knots were used qua mid-lilne eyes!?

Quote
Worse misspelling than 'prussic' even, this 'PET' vice 'TIB' !!

Not all of my *bowlines* are PET or TIB (some are),
but the PET ones by definition are thus when attached
--to ANYthing!

Why do you say that, Dan?
Am I missing something?
?!  "post-eye tiable" implies that one can --indeed,
that one MUST be able to-- tie the knot after attaching
the line to the <anything, including harness> .  Now, by
Agent_Smith's response, I see the *technicality* that
only the first eye can be PET-made but then one must
have the extant partially completed nub there when
making eye#2 (if not doing the jump-rope tying of taking
a twin-eye bight-end around the body and all!).

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on April 01, 2017, 04:28:59 PM
My point was that trying to form an attachment with #1080 to a climbing harness via the TIB method is problematic. I stated that is COULD be done - but, it would be a ludicrous process.
As I've recently (self-)triumphed in figuring out how to tie
a fig.8-(or 9-...)based eyeknot with just such a "jump-rope"
maneuvre, I will gainsay "ludicrous".  (My triumph : pull bight
up through smallish eye of e.g. overhand eyeknot and then
twist it a few times (damn nasty torsion creator, this) and take
it around the body :: point is, the resulting eyeknot canNOT come
untied sans reversing that, which isn't going to happen; and it's
unlikely to have the oh-eyeknot component come untied, either
(nor be heavily loaded, being the returning eye leg & tail both).
BUT, concern for this particular fig.8 structure is how it might
loosen, still-tied-topologically or not --that is a concern.

Quote
Dan, the 'Myrtle' (in my view) does have a collar.
Hmmm, then what eye knot does not have one?
I see out & back in-reverse (bight-forming) as a collar,
or as #1033 does though not actually "back in" (the rabbit
hole, nipping loop),
vs. out-&-around-in-same-direction, which makes for me
"loop" vs. "bight".

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on April 07, 2017, 12:01:34 AM
Quote
Quote

Dan, the 'Myrtle' (in my view) does have a collar.

Hmmm, then what eye knot does not have one?
per Dan Lehman

The nuances and complexities of language (particularly English) - makes it hard to capture every possible case - sort of like legislation (law) always seems to have loopholes and issues with interpretation.

Here is my understanding - based on many discussions, analysis and debates herein the IGKT:

A collar is a special structure in a Bowline. It has the following characteristics:
[ ] it performs a U turn around the SPart
[ ] it has an entry leg and and exit leg
[ ] the entry and exit legs are encircled and gripped/crushed by a functional 'nipping loop' (and the nipping loop is loaded at both ends)

Some qualifying remarks:
1. The common #1010 Bowline has a classically formed collar structure - a U turn around the SPart and the entry and exit legs lie in parallel. It is easy to recognize. Things get tricky where the collar structure is not classically formed.
In my view, the legs of the collar do not need to be in perfect parallel alignment - that is, they may cross each other (eg #1033 Carrick loop).

The nipping loop has been defined - it also has particular characteristics - such as tension force existing at both ends - when load is applied to the knot.

Example (thought experiment):
#1047 F8 eye knot does not have a 'collar'
1. There is no nipping loop in #1047...and therefore nothing grips entry + exit legs (because they dont exist)
2. The legs of a collar must be encircled and gripped by a nipping loop - again this does not exist in F8 eye knot
3. F8 eye knot is disqualified from being a member of the Bowline family - it has a completely different structure.

We can perform the same thought experiment on other 'eye knots'.
The test is:
1. Does the knot structure have a nipping loop?
2. Does the knot structure have a collar (which performs a U turn around the SPart and has 2 legs)
3. Are the entry & exit legs of the collar encircled and gripped by a nipping loop?

Summary:
1. The collar and the nipping loop are closely linked structures, each having distinct characteristics.
2. The collar always performs a U turn around the SPart and it has 2 legs; an 'entry' leg and an 'exit' leg.
3. The nipping loop encircles and grips both legs of the collar.
4. The legs of the collar do not need to lie in parallel - they may be crossed.
5. If there is no nipping loop, this automatically disqualifies a knot structure from being a 'Bowline'.

Mark G

Edited for clarity and to wrap up with a summary.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on April 07, 2017, 10:24:56 PM
Quote
If there is no nipping loop, this automatically disqualifies the structure from being a 'Bowline'.

But the recent question was re "collar",
and note that your def. of it requires a nipping loop,
which I think you might want to retract?!

In any case, as I said, I lean more towards bight vs loop
in seeing a collar vs. not.

As for "nipping loop", well, there comes the issue of any
significant tension to satisfy that "both ends" aspect; I
think that this'll be problematic (though I am sympathetic
to the assertion vs. sheet bend).

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on April 09, 2017, 04:38:52 AM
Quote
But the recent question was re "collar",
and note that your def. of it requires a nipping loop,
which I think you might want to retract?!
per Dan Lehman

No retraction required.
The collar and the nipping loop are separate structures - with each having its own distinct characteristics.
Possibly confusion caused by the 'relationship' between these two structures within the Bowline.

Some Bowlines do not have classically formed collars (which includes both legs).
An example is #1033 (Carrick loop).
The nipping loop is easy to see in #1033.
I suspect that the collar structure is not so obvious to some observers - and so it is dismissed as being a 'Bowline' variant.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: knotsaver on April 10, 2017, 04:50:57 PM
Does the PET quality of an eye imply easiness of untying it?
No.
And "easy to untie" is a YMMV per materials, forces, & needs
...

Yes, but the geometry and the way the knot is loaded are important factor for instance

I saw this knot (perfection/anglers loop once
in some commercial-fishing/-marine cordage lying about,
and it appeared that the knots were used qua mid-lilne eyes!?

I think in that way the perfection/anglers loop perhaps is more easy to untie, because by loading the other end the nub doesn't jam as in the normal case (without loading the other end).

"post-eye tiable" implies that one can --indeed,
that one MUST be able to-- tie the knot after attaching
the line to the <anything, including harness> .  ...

ah, ok, I had misunderstood. Thanks.

Ciao,
s.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on October 17, 2017, 10:29:51 AM
Just posting some comments from Xarax re the 'collar'.... as his 'proxy'.

Quote
The nipping loop is the primary characteristic, indeed - but we should not underestimate the role of the collar , the "proper" collar (  the "invention" of the collar sealed the fate of the bowline s development. It was as ingenious a step as the invention of the nipping loop ). Those Myrtle+stopper "bowlines", for example, are not bowlines enough ! 😉☺ The "proper" collar, which collars the Standing End ( standard bowlines ) or the ongoing eyeleg ( "Eskimo" / anti-bowlines ), seems a much simpler, and much more advanced solution. The Myrtle "collar" is a "link", not a "proper" collar.

The white background images are mine...thought I'd add them for further clarity...

Edit: Outdated image corrected...
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: KC on October 19, 2017, 12:54:46 PM
Quote
I have to go with what DerekSMith said. One of the fundamental aspects of a bowline is the inclusion of a Sheet bend.
"...
In my personal view, there is no functional nipping 'loop' in a Sheet Bend. And the Sheet Bend is not an eye knot.

And this comes back to what is the definition of a 'loop' (and indeed...what is a 'nipping loop'). I had required that the nipping loop must be loaded at both ends in order to qualify. In a Sheet Bend - the nipping structure is not loaded at both ends...and so it is not a 'nipping loop'.
..." Mark Gommers
.
i think though, loop draws close just the same, powered by same SPart;
just Sheet has a stop, Bwl draws thru but  to only half load on other side, other half is on other side of eye, trying to escape choke of nipping loop *.
.
Kinda same structure to start, with forces flowing thru differently;
>>Sheet would have fully loaded tail trying to escape nipping non-loop  vs. Bwl only half force tail trying to escape
>>both instances have same key deformity in SPart
.
The re-route of force does allow forming eye for Bwl as it's added innovation
>>but i do believe it inherits some structure and properties from Sheet Bend
.
i do have a hybrid, been playing with, and will draw out over weekend; have tested it out even more with hurricane work of late; and it has been a good friend.
And some pictures here show softening it as 1 route;
but i try to offload/re-route some of the force around the deformity instead with basically coils around SPart from tail to carry part of finite load that route, around major deformity of nipping loop.
.
edit:

(http://mytreelessons.com/images/kc_bwl_3.png)
.
Seems in well dressed form:
Left half of eye-load carries on 'spiral' routing around nipping loop (below it)
>>would seem if nipping loop is still major deformity/ defining weakness:
>>if half loaded on that leg of eye support, would only have half the in-efficiency(?)
.
Seems also that nipping loop could pass some load to spiral w/o fully routing thru major deformity of nipping loop
>>especially if upgrade nipping loop to RT.
.
Seems forces tracing thru spiral grips SPart above major deformity and perhaps stabilizes that area as load forces re-join to SPart.
Spiral ('linear RT'?) seems would add some extra dynamics to line
>>but would also seem spiral area stiffens area of line and easier to leverage against line on some occasions possible
>>this would be for eye connection, not running bwl.
.
i always look to compare lacings to base lessons of things like this to basics of Square/Sheet/Surgeon's etc. ;
this design shows the pull across loaded SPart as Sheet vs. pull along SPart like Surgeon's from either side of the eye!
.
Normal Bwl all eye loading forces trace  thru and combine at major deformity nipping loop to then transfer to SPart.
i favour several other forms of lacings with the 'spiral' / 'linear-RT' build in slings and other eyes.
.
*Sheet vs. Bwl Nipping is Hitch vs. HH ; perhaps even different forms of HH?
>>And in end, both hand over full force load to SPart at the same most deformed part of highest loading and changes/impacts.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on November 05, 2017, 05:54:38 PM
Hi KC.

You may be interested in this thread. > http://igkt.net/sm/index.php?topic=4283.0 (http://igkt.net/sm/index.php?topic=4283.0) It has some variations on the theme.

At one time I did an adhoc test, tug of war style, using the braided bowline against a simple locked (mine) version of the #1010 using 6mm rope and the braided specimen was the loser. It broke at the location where the sp entered the nipping area. I had hoped that some force would have been dissipated along and through the braid weave. It is very secure though, just not as efficient of rope use as other eye knots.

SS
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: KC on November 15, 2017, 12:08:52 PM
Wow, thanx!
.
Really seems you are trying to watch for same signatures and properties and dressing to allow them.
Really seems like 1 side of eye slips thru nipping loop to be carried on the weave, and introduced over distance , separate from other half of load on eye for less immediately impacting change.
.
Are you saying broke outside of braid as Nip or in braid sheath before Nipping loop?
>>noted  distortions ?
>>will be trying myself , but have no dynamoter (any more!) etc.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on November 15, 2017, 01:47:28 PM
YW KC.

It was hard to watch at the same time as applying the load, but it looked like the spot of contact, just after the braided collar as the nipping loop encircled the bight legs. So, I concluded that there was no significant shedding of load along the braid. Super secure though.
The constriction and first bend at the nip led to the rupture. That is where the markings I had put indicated as well.

SS
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on November 15, 2017, 05:35:48 PM
... but it looked like the spot of contact, just after the braided collar
as the nipping loop encircled the standing part.
So, I concluded that there was no significant shedding of load along the braid
Firstly, I don't follow the highlighted text : the nipping
loop aka "turNip" IS the SPart (making its initial turn);
it encircles the bight legs of the (here, quite extended)
collar.

As for shedding of force via the "braid", well, no,
that must be seen as a pipe dream : the SPart gets
--in a theory ignoring friction : i.p., the effect
of the (why do we call it ...) nipping loop.
The SPart will, in relatively elastic cordage,
stretch thus *thin*, making an even skinnier thing
for the braid to grip, alas.  But the braid isn't getting
even 50% force continued; the imbalance is aggravated.

There are some eye knots in which one can arrange
for the pair of 50%-loaded eye legs to jointly
oppose effects of the SPart, maybe to good effect.
Of course, there is the midshipman's knot / tautline
hitch
structures to do this, where if load isN'T shared,
then ... slippage (noose effect).  (And in such a structure,
one might expect "coil-away" hitches such as ProhGrip
/Blake's hitch
to prove stronger than a rolling hitch
in that their initial, stronger turns come near the eye,
which point the SPart has had to pass through some
possibly lesser gripping (& so, hurting) of the away
wraps!?)

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on November 16, 2017, 12:05:41 AM
I've edited my post. Just got in a hurry. Thx.

As for: "As for shedding of force via the "braid", well, no, that must be seen as a pipe dream".
Well,  disagree, in part. The Australian braid fishing loop counts on this shedding/sharing of load. I don't see how this would not work with Rope knots.  http://igkt.net/sm/index.php?topic=863.msg5711#msg5711 (http://igkt.net/sm/index.php?topic=863.msg5711#msg5711)

In the case of my own experimentation, I just didn't add enough braided crossings. Too ungainly, although it made for a mighty secure loop, imo.
It was worth the effort to find out though.

SS

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on November 16, 2017, 02:17:33 AM
As for: "As for shedding of force via the "braid", well, no, that must be seen as a pipe dream".
Well,  disagree, in part. The Australian braid fishing loop counts on this shedding/sharing of load.\
I don't see how this would not work with Rope knots.

Well, there's the big difference in materials AND in setting forces
(and length!!)--you really need that far reach of the braid to bite
that's hard to accomplish.  If the nipping loop bites --and
recall that that's the whole *game* for a sheepshank!--,
one doesn't get tensioned gripping in the braid (unless the
away/SPart end of it is biting and pulling away with the
SPart's draw.  Then, again, in esp. dynamic ropes,
the change of diameter differences in SPart/eye-leg
create the smaller object to be gripped.

such as a 5:1 pulley with body weight, which even
is a good way to see things that armchair pulling
on might not notice.
(AND, on the other hand, as I noted for the offset
water knot/EDK
, doing low-force puling can
reveal things a single hard pull misses --I was amazed
to see the choking line of that knot just continually
ratchet out, tail consumed (why Mark insists on equal
tail sizes : a measure 2 B Sure if things are behaving,
well, at least in the case of biased slippage).

I came up with what I hope might go some way towards
of line that we seek for boosted strength
by designing some eye knots in which the twin eye legs
oppose pretty fairly the single SPart's twist.  I.e., the
eye legs --at the eye end of the nub-- presumably will
dominate forces there, and in trying themselves to
UNtwist their helical turning, impart --not merely,
passively resist-- twist to the SPart and a part that
it twists with.  (In the Bimini twist, the outer wraps
merely resist the internally twisted SPart from UNtwisting;
my knot(s) actively twist (in theory).)  At the
SPart's end of the knot, it will dominate (by then,
much force of eye legs has been consumed), and it
will pull straight, un"twist"ing and put all the curvature
into the part it had equally "twist"ed with, making that
part now "wrap"; but hope is that before the SPart
makes its U-turn (unlike B.Twist), its being twisted
is *enforced* by the eye legs.

(Then we see some tests that put simple knots
such as the bowline & fig.8 eyeknot at around
80% --even higher, in a case tested by Tom Moyer--
and we should question to value to getting higher
strength at such cost of knotting ingenuity/complexity!)

(In angling, it seems that high strength --apparently--
can come by (way!) understating line strength : I've
seen tests where knots come out stronger! )

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: KC on November 16, 2017, 11:40:58 AM
To my eye;
The 'braids' pull away from eye if well set; the turNip pulls into eye.
>>Thus, i think we can see turNip pulls more across SPart deforming it, than braids pulling along roman column length of SPart.
The braids and other friction hitch type builds preserve the 'sanctity' of pure inline SPart, as HH/turNip bases outrightly deform SPart.
As the pull along SPart can be made to stand further from mount it can be shown:
A>Doesn't pull across
B>slants SPart less
C>eventually can visualize as extra leg of support/ load sharing thru deforming parts, rather than all force thru or even at major deformity.
.
Whereas ; in a standard Bowline, all the force hand-off from both legs of eye to 1 SPart seems at one point,
>>in braids version the hand-off from  dual to single seems more gradual,where would seem to be more favored/forgiven.
.
The braid side is an theoretical extension of RT around SPart; giving back some strength of simple Turn deformity; limiting some  the  raising of tension beyond load, to allow less usable capacity 'strength loss'.
.
Final deformity braids assumes before breaking may be a reason not to work or perhaps, in a glass fiber concept(to me): back pressures of major turNip deformity coming thru line overloading only later after braids add load??!!?  Very Interesting in any aspect!
.
Braids Bowline is more secure, gives nice look and weight to end of line (but then also stiffened area that can leverage against line); but yes the main target for the extra 'labor and materials' is strength; these are only side attributes to that un-hit target.
.
(http://mytreelessons.com/images/braid_bowline_slip_knot.png)
.
(http://mytreelessons.com/images/braid_bowline_forces.png)

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: SS369 on November 16, 2017, 02:09:11 PM
KC,

You have the SP straight through the braid, in your graphic (Thanks for it.), and that doesn't show what I had devised and thought at the time that I did my pull tests. The SP should be crossing with the pre-collar parts.
Hopefully the picture attached will show what I mean and where I had marked the parts to be able to inspect  during and after the pull.

SS
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: KC on December 11, 2017, 01:43:40 PM
Over the weekend i found rather favorable results with this lacing strategy.
>>except 1 piece of stiff cord i had single piece of
>>but this strategy did prove weaker in it 2x
.
using:several small line types/several paracord:
Tied in 1 end as i've shown;
Tied on other end with Standard Bowline with Overhand Stopper
Each Bowline eye had a matching carabiner to it;
>>pulled between truck (frame pull) and tree.
.
much longer(than test eye2eye line) line to same carabineers;
>>to catch kickback of eye2eye line snapping
.
Offered even truck pull until line break, no jerk/impact action.
>>small Toyota p'up, small lines is my present testing radius.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 23, 2018, 12:54:40 AM
per Derek:
Quote

A Bowline has the following key aspects:-

[ ] A Bowline has two defining internal components, these being a Bight Component and a Helical Nipping Component, plus two defining external components, these being a load bearing SP and a load bearing fixed loop.

[ ] A Bowline may contain other components, but these must not change the form or function of the two key internal components.

[ ] The Bight Component collar must encircle the SP in order to stabilise the Bight Component, although in use the collar may become distorted and lead to eventual failure of the bowline - this is a continuous progression through various degrees of Bowline viability.

[ ] The legs of the Bight Component must be secured by and within the Helical Nipping Component.  This action provides the negative linear cogging function within the knot and is a critical aspect of knot functionality.
One of the Bight Component legs must be a loop leg.
the remaining Bight Component leg is normally the WE, but may be reworked to enhance security, but must not change the form or function of the defined key internal components.

[ ] The Helical Nipping Component must be loaded on both ends.  One end must be loaded by the SP, the other must be a loop leg.  The helical Nipping Component may range from an overlapped helix, through a spectrum of degrees of openness.  In use, the helix may continue to open if the bight legs are drawn through the grip of the Helix, eventually leading to loss of viability as a fixed Loop Knot and conversion to a Noose.

[ ] This definition is based on ABOK #1010, but does not extend to incorporating the Eskimo 'Bowline', wherein the Bight collar does not encircle the SP.

It incorporates a considerable amount of flexibility, yet retains the core essence of the Bowline.  The price is that the Eskimo will probably have to become known as the Sheetbend Loopknot ....

Derek

With a few modifications to your chosen terminology, this is largely what I and others have been advancing for some time (but maybe you did not see this?). Problem areas are highlighted in red font.

The nipping structure (or nipping component) - in the common #1010 Bowline - takes the form of a jam resistant helix that is loaded at both ends and is TIB (Tiable-In-the Bight). To Ashley's eye, all 'Bowlines' contained this type of nipping component.

Things get difficult when we see nipping components that take a different form to a helix. For example, there is #206 Crossing hitch and #559 Marlinspike hitch. Both of these structures are TIB and can be loaded at both ends and remain jam resistant.
In my view, it is possible to construct a virtual Bowline from a nipping component that takes the form of #206 and/or #559. The word 'virtual' meaning "in the likeness of" or, "a close representation of".
The use of 'TIB" as a qualifier for a nipping component assists in narrowing the potential for other eye knots to claim the title of 'Bowline'.

In my view the illustration at #1016 (in 'ABoK') is a clue to Ashley's mindset - and shows a [previously functional] nipping loop that, due to a transformation, has become non-functional. I think Ashley recognised that the nipping component needed to be loaded at both ends and be free to encircle and clamp both legs of the collar. In #1016, due to the transformation, the nipping loop has lost functionality. And that (in my view) is why Ashley was hesitant to call it a 'Bowline'. Xarax has also advanced that a nipping component (or nipping 'loop') is most effective when it begins at the continuation of the SPart (standing part).

A further qualifier for a nipping component is that it must freely be able to encircle and clamp both legs of the collar (which you prefer to conceptualize as a 'bight'). When this condition is satisfied, it is said to be 'functional'.

The collar does not need to encircle the SPart (standing part). It performs a U turn around it (not a full circle). This U turn may be performed at the crossing point formed at the juncture of the SPart and the ongoing eye leg (ie so called 'Myrtle Bowline'). The SPart acts as a bracing post.

The 2 legs of the collar may enter the nipping component from opposite directions (in the common #1010 Bowline, both legs enter from the same side).

Xarax is working on a theory about 'PET' (Post Eye Tiable) qualifier - but I am unclear as to how far he has progressed with respect to its completion. In earlier theories, it was advanced that all 'Bowlines' are PET.

With respect to your phrase 'degrees of openness' (re a helix) - a more accurate descriptor is degree of overlap. If the helix were to 'open up' (which I understand to mean spread apart so that there is no longer any contact between the overlapping segments) - it would no longer be functional.

I disagree with your proposition re the so-called 'Eskimo Bowline' (which is an anti-Bowline).
All the necessary building blocks are present - just all in an 'anti' direction relative to the common #1010 Bowline.

And; your use of the term 'loop' may be fluid and diluted - because a loop is a geometry that is not well defined in knotting literature. Some may argue that what you conceptualise as a 'loop', is more apt to be described as a fixed 'eye' (analogy is an 'eye bolt'). The concept of 'loop knot' is likely heavily influenced from the days of Ashley - and has become entrenched. To challenge that paradigm is to invite risk - because the concept of 'change' can induce feelings of fear, and in some cases, outrage. It is a human condition to fear change. And so, to substitute the phrase 'eye knot' for 'loop knot' could ignite fear and outrage. I think that knotting terminology needs to be better defined.

I am currently working on a revision to my analysis of Bowlines paper. I have a rich source of material and ideas to inject into that paper.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 23, 2018, 03:45:51 PM
My actual proposal went like this (numbered now for clarity) - without the exclusion of line 6, which I am confident was only a transcription error.

• A Bowline has the following key aspects:-
• A Bowline has two defining internal components, these being a Bight Component and a Helical Nipping Component, plus two defining external components, these being a load bearing SP and a load bearing fixed loop.
• A Bowline may contain other components, but these must not change the form or function of the two key internal components.
• The Bight Component collar must encircle the SP in order to stabilise the Bight Component, although in use the collar may become distorted and lead to eventual failure of the bowline - this is a continuous progression through various degrees of Bowline viability.
• The legs of the Bight Component must be secured by and within the Helical Nipping Component.  This action provides the negative linear cogging function within the knot and is a critical aspect of knot functionality.
• One of the Bight Component legs must be a loop leg.
• the remaining Bight Component leg is normally the WE, but may be reworked to enhance security, but must not change the form or function of the defined key internal components.
• The Helical Nipping Component must be loaded on both ends.  One end must be loaded by the SP, the other must be a loop leg.  The helical Nipping Component may range from an overlapped helix, through a spectrum of degrees of openness.  In use, the helix may continue to open if the bight legs are drawn through the grip of the Helix, eventually leading to loss of viability as a fixed Loop Knot and conversion to a Noose.
• This definition is based on ABOK #1010, but does not extend to incorporating the Eskimo 'Bowline', wherein the Bight collar does not encircle the SP.

It incorporates a considerable amount of flexibility, yet retains the core essence of the Bowline.  The price is that the Eskimo will probably have to become known as the Sheetbend Loopknot ....

Derek

Quote from: Mark
With a few modifications to your chosen terminology, this is largely what I and others have been advancing for some time (but maybe you did not see this?). Problem areas are highlighted in red font.

Or perhaps I have always held this view but not expressed it with sufficient clarity or with the appropriate terminology ?

Of the five exceptions you have highlighted within the definition, three of them relate to my use of the term Loop Knot, presumably in contradiction to your preferred term Eye Knot.  I have to say that I admire your fortitude and persistence in your attempt to justify the renaming of all Loop knots as Eye knots.  But isn't it about time that you accepted the fact that even on here, the majority of knotters reject your arguments attempting to support the change and are telling you that we will continue to call Loop knots by the term we all understand - Loop knots.  Some, including myself, have acknowledged that a specific subset of Loopknots justify the additional sub classification of Eye Knot, when they are small, with parallel legs and suitable for the inclusion of a Thimble.  Without anything new of significance to add to your rationale for such a significant change, I would urge you to consider getting back into step with the majority.  To persist with your
fixation is only adding unjustifiable confusion.

Of the remaining two problems, the first is my use of the term 'encircle' describing the need for the bight turn to contain the SP.  I have to admit, that the term 'encircle' contains an inference that the Bight collar FULLY encircles the SP.  Would you feel better with 'contains' or 'encloses'?  The Bight Component has three sub components :- the Turn subcomponent (AKA collar) and two Leg subcomponents.  While identifying these parts of the Bight Component has value, it is critical to understand that the Bight Component functions within a knot as an entity.  You focus often on the Collar legs, with the emphasis being on the Collar subcomponent, but in function, the Turn (or Collar) has only the function of retaining the orientation of the Bight legs.  Having been restrained by the Bight Turn, the Bight Legs are then able to perform two critical functions within the Bowline.  The first is to keep the Nipping Helix Component in the correct orientation and to resist the propensity of the helix to rotate and open.  It achieves this from the tension between the external Loop Leg and the Turn around the SP.  The second, and perhaps the most critical part of Bowline performance is that it provides the only significant source of negative linear cogging in the whole knot.  There is a lesser amount of negative rotational cogging with the nipping turn, but without the negative linear cogging between the bight legs, the Bowline is fatally compromised.

Hopefully from this description you will see that it is the Bight that is critical, not just its 'collar'.  [NB this is born out by observations in the wild where loading has led to extension of the Bight such that the Turn (Collar) is virtually flapping in the wind, yet the knot defies decomposition.]

Quote
The 2 legs of the collar may enter the nipping component from opposite directions (in the common #1010 Bowline, both legs enter from the same side).
If I understand your above statement, it indicates that you have had no perception of negative linear cogging.

Quote
With respect to your phrase 'degrees of openness' (re a helix) - a more accurate descriptor is degree of overlap.

A helix, even when there is zero gap between its coils does not have any overlap.  Therefore using the term 'overlap' to describe how far apart the coils have moved is counter intuitive.  By talking about 'overlap' you are moving from the spectrum of plain helix forms into the far end of the Nipping Component spectrum where the nipping turn starts to become a Simple Hitch which is present in many Bowline examples and to a very large extent provides its own end loading - i.e. it does not need external loading from the loop leg.  Although I accept this end of the spectrum, I doubt you do.

Finally, might I make a request - that you first develop a robust understanding and definition of The Bowline i.e. #1010.  Not just one that describes the idealised knots of your excellent photographs, but a definition and understanding robust enough to apply to the vast array of #1010's that are created every day, and which morph under usage and in different cordages encountered in the wild.

Then you might be sufficiently aware of what The Bowline is, to be justified in encompassing other knots into that definition.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 24, 2018, 02:56:42 AM
per Derek:
Quote
But isn't it about time that you accepted the fact that even on here, the majority of knotters reject your arguments attempting to support the change and are telling you that we will continue to call Loop knots by the term we all understand - Loop knots.

This is a phenomena known as 'social proof'.

I am happy for you to conceptualise an eye knot as being a loop knot and having a loop.

Quote
If I understand your above statement, it indicates that you have had no perception of negative linear cogging.
I have significant doubt that you understand what my level of understanding is.
Your reference to my perception is biased from your own viewpoint. You are being challenged and your mode of reaction is normalised to defending your own viewpoint.

Quote
Finally, might I make a request - that you first develop a robust understanding and definition of The Bowline i.e. #1010.
Interesting comment - but predictable.
You feel that you are being challenged - so you are compelled to devalue the theories and understandings advanced by your perceived opponent.
Some of these feelings are linked to the notional concept of change - and the idea of change can evoke strong emotions in some individuals.

Although the notional concept of 'change' (in this case) may be misplaced.
Two parties with differing perceived viewpoints can be mirrored on a global scale with the analogy of different national ideals and indeed, even within national boundaries as political parties with differing viewpoints. Usually, when the parties are willing to take a different viewpoint, many aspects may in fact be the same, just clothed in a different language.

If I may make a request of my own... taking an adversarial approach to arguing a theoretical concept is going to lead nowhere. Using social proof to advance support for your own arguments is invalid. Perhaps a collaborative approach may yield more positive outcomes?

You are welcome to write a theory of your understanding of what constitutes a 'Bowline' - and I would be happy to insert it into my upcoming revision to my 'Analysis of Bowlines' paper.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: B.P. on August 25, 2018, 10:35:10 PM
In my view, it is possible to construct a virtual Bowline from a nipping component that takes the form of #206 and/or #559

Hello agent_smith,

I hope you didn't miss this thread : http://igkt.net/sm/index.php?topic=6151.0

Thank you for the paper about bowlines, I read it many times before my publications on the present forum.

I also share, probably among other things, your interest about tests and terminology.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 26, 2018, 03:03:41 AM
Quote
Hello agent_smith,

I hope you didn't miss this thread : http://igkt.net/sm/index.php?topic=6151.0

Bonjour B.P. !

Note: Bonjour is virtually the limit of my French speaking skills  :o

I replied to your other post.
I like your creation very much - it has an elegant geometry (in my opinion).

I have tendered my opinions in that thread...but:
I have used the phrase 'virtual Bowline' to describe your creation.

I think Derek would strongly request that I add a qualifying remark to practically all of my posts on this forum that:
"None of the information tendered by agent_smith represent the opinions or views of the IGKT or its members".
I might need to add a 'tag line' to all of my future posts with words to that effect so as not to raise too many alarm bells!

I had attached a very specific meaning to my use of the word 'virtual' as follows:
Almost or nearly as described, but not completely or according to a strict definition.
Almost a particular thing or quality.
Almost, but not exactly or in every way.

First order Bowlines (or Bowlines of the first order), have a nipping structure that is based directly on a helix that is loaded at both ends (and TIB).

My use of the phrase 'first order' or; 'of the first order' is my invention (and does not represent the opinions and views of the IGKT). Mind you, having to insert this disclaimer each and every time is tiresome - because it could be argued that every post on this forum does not represent the views of the IGKT or its members (obviously, its just one persons opinion)!

Anyhow, I am writing an update to my analysis of Bowlines paper - and I would like to add your creation to that paper (with your permission!).

The updated paper will attempt to classify all 'Bowlines' as follows:
1. First order Bowlines (or, Bowlines of the first order)
2. Virtual Bowlines
3. Anti-Bowlines

I have come under heavy friendly fire from Xarax for using the word 'virtual' - because he strongly feels that in the modern age, it has become associated with computer generated imagery.
I have countered Xarax by stating that as long as I provide a glossary to define each term, the meaning should be as I intended.

Wish me luck!

EDIT NOTE: There is something wrong with viewing attached images - I think the webmaster ('mistress') needs to investigate. Uploading new images also seems to be problematic...
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 28, 2018, 03:15:48 PM
PART 1 of 2

#1033 Carrick 'loop' has always interested me.
This particular eye knot should not be confused with the #1439 derived Carrick eye knot.
They look very similar - but not quite.
The #1033 structure does not have a uniform over-under-over-under weave pattern.
Also, it does not undergo a transformation when load is applied - it retains its form.
And furthermore, there is no #206 'Crossing hitch' structure (as with #1439).

In my view, a possible scenario is that Ashley was not aware of the #1439 derived eye knot - because if he had held both knots in a side-by-side examination, he might have spotted the subtle difference. And so, because #1033 (for all intents and purposes) had the 'appearance' of the #1439 Carrick structure, he decided to attach the title 'Carrick' to its name.

It is my own view that #1033 is more aligned to the family of 'Bowlines' than it is to the 'Carrick bend'.
However, it isn't one of the 'first order Bowlines' (or 'Bowlines of the first order).

I am of the opinion that it could fit within a class of 'Bowlines' called 'virtual Bowlines'.
This is a descriptor I had devised - largely due to dissatisfaction with alternative descriptors such as 'pseudo Bowlines', or 'para Bowlines', or 'quasi Bowlines'.

I intend the term 'virtual' to have the following meaning:
Almost or nearly as described, but not completely or according to a strict definition.
Almost a particular thing or quality.
Almost, but not exactly or in every way.

And the term 'First order Bowline' (or 'Bowline of the first order' - examples include: #1010, #1013 etc):
Of major importance or significance.
Used to denote something that is excellent or considerable of its kind.
A thing having the highest status in a group.

...

The bottom 3 images are EN564 Sterling 8mm cord at the following load milestones:
[ ] 1.0kN
[ ] 2.0kN
[ ] 4.0kN
(each successive image doubles the load)
No instability or insecurity was observed up to 4.0kN peak load.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 28, 2018, 10:31:20 PM
It's the initial geometry/(non-)setting that is the challenge
--i.e., NOT to (over-)tighten but to leave the tail's circuit
through the initial turNip *relaxed*.  For to tighten it in
most any way will want to bend one or the other ends
such nice stability!  --and not seen is the vast openness
of the collar around the outgoing eye leg.

Thanks,
--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 29, 2018, 12:49:00 AM
PART 2 of 2

I have attached a side-by-side comparison of #1033 Carrick 'loop' versus #1439 derived Carrick 'loop'.
In my previous post, I had tendered a theory that Ashley did not examine [a] corresponding eye knot derived from #1439 Carrick bend.

I'm not even sure that he had outlined a theory about the correspondence between 'bends' and 'eye knots' (aka loop knots). Note that this 'correspondence' with the eye knot form can take on different forms according to which ends go where.
Although, given that Ashley did insert the word 'carrick' into the name of #1033, he presumably understood some level of 'correspondence' between bends and eye knots - but did not expand upon it. I seems that Harry Asher may have been among the first to try to expand the theory?

I am of the view that #1033 has a closer affinity with the family of 'Bowlines' than a 'Carrick bend'.
And indeed, #1033 has a functional nipping structure that takes the form of a single helix that is loaded at both ends (and is 'TIB'). Both legs of the collar are fully encircled and clamped by the nipping structure.

Xarax has pointed to his dislike of the 'collar' in #1033 - and of course, this is one of the structural characteristics why #1033 cannot be regarded as a 'first order Bowline'. The other being that the legs of the collar enter the nipping structure from opposite directions.

It does (in my view) meet the definition I tendered for 'virtual Bowline'.
Almost or nearly as described, but not completely or according to a strict definition.
Almost a particular thing or quality.
Almost, but not exactly or in every way.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: B.P. on August 29, 2018, 01:33:55 AM
Quote
Hello agent_smith,

I hope you didn't miss this thread : http://igkt.net/sm/index.php?topic=6151.0

Bonjour B.P. !

Note: Bonjour is virtually the limit of my French speaking skills  :o

I replied to your other post.
I like your creation very much - it has an elegant geometry (in my opinion).

Thanks again

I have tendered my opinions in that thread...but:
I have used the phrase 'virtual Bowline' to describe your creation.

I think Derek would strongly request that I add a qualifying remark to practically all of my posts on this forum that:
"None of the information tendered by agent_smith represent the opinions or views of the IGKT or its members".
I might need to add a 'tag line' to all of my future posts with words to that effect so as not to raise too many alarm bells!

I had attached a very specific meaning to my use of the word 'virtual' as follows:
Almost or nearly as described, but not completely or according to a strict definition.
Almost a particular thing or quality.
Almost, but not exactly or in every way.

First order Bowlines (or Bowlines of the first order), have a nipping structure that is based directly on a helix that is loaded at both ends (and TIB).

My use of the phrase 'first order' or; 'of the first order' is my invention (and does not represent the opinions and views of the IGKT). Mind you, having to insert this disclaimer each and every time is tiresome - because it could be argued that every post on this forum does not represent the views of the IGKT or its members (obviously, its just one persons opinion)!

Anyhow, I am writing an update to my analysis of Bowlines paper - and I would like to add your creation to that paper (with your permission!).

Obviously you don't really need any permission, it's your paper, nevertheless you have it  :)

The updated paper will attempt to classify all 'Bowlines' as follows:
1. First order Bowlines (or, Bowlines of the first order)
2. Virtual Bowlines
3. Anti-Bowlines

I have come under heavy friendly fire from Xarax for using the word 'virtual' - because he strongly feels that in the modern age, it has become associated with computer generated imagery.
I have countered Xarax by stating that as long as I provide a glossary to define each term, the meaning should be as I intended.

Like I already told you on the topic "2 keys knot - Noeud a deux clefs" :
I think that I need more time to study these questions, hoping to find (my) answers to share

but I'll maybe share questions too   ::)

Wish me luck!
I wish you the best, courage and luck.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 29, 2018, 01:52:34 AM
per B.P.
In relation to the use of the term 'virtual'...
Quote
Like I already told you on the topic "2 keys knot - Noeud a deux clefs" :

Thanks B.P.

Like I stated elsewhere, the key to understanding is to have a glossary of terms.
As long as the author of a paper supplies clear and succinct definitions, all should be good.

It is up to the reader of the paper to either ignore those definitions or, to interpret them in the way the author had intended.

As I also pointed out, some readers may subconsciously apply their own interpretation regardless of what the author had intended. How do you deal with these type of people?

NOTE: ...please understand that my reply is not intended as a 'fight'! We are not sitting face-to-face in a normal human interaction. Its just typed words on a keyboard.
I am simply engaging with you on an intellectual level :)
I used the quote function to aid in meaning and to give a context for the discussion.
We are just discussing concepts... nothing bad or sinister here!
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 29, 2018, 11:15:55 PM
My actual proposal went like this (numbered now for clarity) - without the exclusion of line 6, which I am confident was only a transcription error.

• A Bowline has the following key aspects:-
• A Bowline has two defining internal components, these being a Bight Component and a Helical Nipping Component, plus two defining external components, these being a load bearing SP and a load bearing fixed loop.
• A Bowline may contain other components, but these must not change the form or function of the two key internal components.
• The Bight Component collar must encircle the SP in order to stabilise the Bight Component, although in use the collar may become distorted and lead to eventual failure of the bowline - this is a continuous progression through various degrees of Bowline viability.
...
• This definition is based on ABOK #1010, but does not extend to incorporating the Eskimo 'Bowline', wherein the Bight collar does not encircle the SP.

It incorporates a considerable amount of flexibility, yet retains the core essence of the Bowline.  The price is that the Eskimo will probably have to become known as the Sheetbend Loopknot ....

Derek
...
Hopefully from this description you will see that it is the Bight that is critical, not just its 'collar'.  [NB this is born out by observations in the wild where loading has led to extension of the Bight such that the Turn (Collar) is virtually flapping in the wind, yet the knot defies decomposition.]

Quote
The 2 legs of the collar may enter the nipping component from opposite directions (in the common #1010 Bowline, both legs enter from the same side).
...
Finally, might I make a request - that you first develop a robust understanding and definition of The Bowline i.e. #1010.  Not just one that describes the idealised knots of your excellent photographs, but a definition and understanding robust enough to apply to the vast array of #1010's that are created every day, and which morph under usage and in different cordages encountered in the wild.

Then you might be sufficiently aware of what The Bowline is, to be justified in encompassing other knots into that definition.

Derek

Which means you cast out "the Myrtle" (eye knot) as being
a *bowline*, as it lacks --critical for you-- the bight component
(except for the eye).

IMO, the sole critical/defining component is the central
nipping loop.  But even in this simplicity things get complicated
But IMO what can be seen/chosen as the *bowline's* essence
is the nipping loop (my "turNip") and its effect at forming
a knot (fortunately, realized prior the introduction of HMPE
slick cordage!).  And given this recognition, there are many
wonderful & simple things that can be done.
Somewhere amongst sets of "bowlines' come those in which
there is something rather different than the simple "turNip"
--e.g., two of them, or a clove hitch-- which then puts this
definition into question; and also the deformation of the loop
into more open helical form (I just got s a few more photos
of Knots In the Wild of such deformation).

<sigh>

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 30, 2018, 07:42:01 AM
per Dan Lehman:
In relation to 'Bowlines'
Quote
IMO, the sole critical/defining component is the central
nipping loop.

and...

Somewhere amongst sets of "bowlines' come those in which
there is something rather different than the simple "turNip"
--e.g., two of them, or a clove hitch-- which then puts this
definition into question

I agree in principle with you.
I believe that it is possible to classify all 'Bowlines' by the geometry of their 'nipping structure'.
It may be more accurate to describe this central nipping component as a 'nipping structure' or 'nipping component'.

So for example, we could look to all of the primary Bowlines illustrated by Ashley - all of which have a nipping structure that takes the form of a helix ('loop') that is loaded at both ends (and is 'TIB'), fully encircles and clamps both legs of the collar and is jam resistant. And structurally, this nipping loop exists at the juncture between the SPart and the ongoing eye leg.
These primary Bowlines include; #1010, #1012, #1013, #1080 etc.
They also have a collar that performs a U turn directly about the SPart.

When the nipping structure doesn't take the form of helix/loop - for example, a #206 Crossing hitch or #559 Marlinspike hitch - it is no longer a member of the class of primary Bowlines.

I had used the term 'virtual Bowline' to identify these type of eye knots that have a nipping structure that doesn't take the form of a helix/loop but nevertheless still meets all other criteria such as 'TIB', loaded at both ends, and fully encircles and clamps both legs of the collar. And I had intended the term 'virtual' to have a specific and restricted definition.

With regard to #1033 Carrick 'loop' - this eye knot has a nipping structure that takes the form of a helix/loop and meets all other criteria (eg TIB, loaded at both ends and fully encircles both legs of the collar, jam resistant, etc)).
Where #1033 differs is the structure of its collar (which Xarax laments isn't a proper collar) and the fact that both legs of the collar enter the nipping loop from opposite directions.

I have tested #1033 Carrick 'loop' to 10kN using EN564 Sterling 8mm cord - and it remains stable and jam resistant. After 10kN load, it was easily untied.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 30, 2018, 09:10:27 AM
@ Dan
Quote
Somewhere amongst sets of "bowlines' come those in which
there is something rather different than the simple "turNip"
--e.g., two of them, or a clove hitch-- which then puts this
definition into question; and also the deformation of the loop
into more open helical form (I just got s a few more photos
of Knots In the Wild of such deformation).

Indeed Dan, this restrictive definition should indeed cast out just about everything but #1010.  This is because it is my attempt to take'one bite of the proverbial Elephant'.  It has been my experience that complex problems may sometimes be resolved by seeing if they can be sensibly broken down into manageable portions (such as my approach to considering a 'nub' as a functioning set of Components).  Of course, some problems can only be understood 'in toto'. but even for these 'holistic' problems, the process of understanding the functionality of sub components may sometimes help in grasping the larger picture.

Once we have formulated a definition that works for The Bowline (#1010), and can be seen to work for the knot at work - 'in the wild', then we have a tool that will allow us to understand how the Bowline works - what makes it 'a Bowline'.  When we have this cornerstone in place, it is reasonable to consider other arbitrarily designated 'Bowlines' by seeing how the definition must be expanded to accommodate them.  In taking that step we give ourselves the opportunity of seeing  what other (self evidently NOT Bowlines) are let into the classification, thereby destroying any value to the definition.

So yes, the definition was deliberately aimed at #1010.  If it works and is found to be robustly acceptable, then we have at least one bite of this 'Elephant' under our control and ready for the next bite.

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: DerekSmith on August 30, 2018, 09:33:52 AM

IMO, the sole critical/defining component is the central
nipping loop.

<sigh>

--dl*
====

Here Dan, I have to admit to a problem.

The nub of #1010 has but two components - the Nipping Helix Component and the Bight Component.

Without both of these components the knot does not exist.
Without the Nipping Helix, the bight legs cannot generate negative cogging and the knot flows out.
Without the Bight legs to bind on, the Nipping Helix collapses and without the Bight collar to stabilise the Bight Component the helix torsion simply twists the bight legs and turns itself into straight cord.

So the clarity I am seeking is to understand what aspect of these functions do you see that leads you to conclude one component to be more elemental than the other?

Derek
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: siriuso on August 30, 2018, 01:46:21 PM
Hi dear all,

In my opinion, Carrick Loop ABOK #1033 is not TIB.

yChan
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 30, 2018, 03:58:52 PM
per yChan:
Quote
In my opinion, Carrick Loop ABOK #1033 is not TIB.

I am not sure what point you are trying to make? Are you are suggesting that being TIB is a pre-requisite for the title of 'Bowline'?

For example, the #1010 primary Bowline also isn't TIB.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: siriuso on August 30, 2018, 04:06:04 PM
Hi Mark,

yChan
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 30, 2018, 04:40:45 PM
Quote
So the clarity I am seeking is to understand what aspect of these functions do you see that leads you to conclude one component to be more elemental than the other?

I understand the reasoning that underpins Dan Lehman's comment.

I personally do not see one component being more 'elemental' (or of higher structural importance) than another (within a 'Bowline'). I hope that Dan concurs!

The nipping structure is (almost without exception) formed first.
The nipping structure is key in terms of jam resistance - and all Bowlines (by definition) - are resistant to jamming.
Once the nipping loop is formed, all 'working end' maneuvers are performed through and around it. Essentially, it is the central building block from which the rest of the knot is built.

Removal of the nipping structure, causes [a] 'Bowline' to cease to exist.

Of course, there are other components that also need to be present - in order to complete the entity we regard as a 'Bowline'.

It should be possible to classify 'Bowlines' according to the type of nipping structure with due regard to the position and orientation of the collar.

EDIT NOTE:
I intentionally omitted the Spanish Bowline (#1087) and Portuguese Bowline (#1072) due to space restrictions and 100KB imposed file limit. To be clear, Ashley did identify these 2 structures as deserving of the title 'Bowline'.
I will also add #1074 (Bowline with a bight) in a future upgrade to my Analysis of Bowlines.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 30, 2018, 04:46:38 PM
per yChan
Quote
If I did specifically state (in clear and unambiguous words) that #1033 Carrick 'loop' is TIB - then it is either a typo or a miscommunication.

#1033 Carrick 'loop' isn't TIB.

Can you please point me to the threads / posts where I used specific language to declare #1033 Carrick 'loop' to be TIB? (I want to go back and delete that reference).

Thanks...
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: siriuso on August 30, 2018, 06:13:58 PM
Hi Mark,

They are in this post :
Reply #370 para.6 and Rely # 374 second last para.

yChan
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: Dan_Lehman on August 30, 2018, 09:06:11 PM
So the clarity I am seeking is to understand what aspect of these functions do you see
that leads you to conclude one component to be more elemental than the other?
Partly, I don't think this is a pertinent question,
in that it suggests that we seek some Trvth of Things
rather than a way to talk about them --an invention
for a purpose, not something Out There 2 B discovered.

But, playing along with some *real* rationale for what
I said, I suppose one can point to concentration of forces,
and even other aspects --perhaps PET (post-eye tying)?--
that support such ranking.
For me, though, it really was just about what it is I want
to have a group of; and so I see this simple "central nipping
turn" as that, and for that component to work, there needs
to be stabilization by the tail's return knotting --but THAT
need not be only a bight.
(Then, though, I am also willing to walk away from the
mere "turNip" for like structures, even non-PET ones,
with, well, "likeness" to the simple loop.  For this, it
might be that I come up with some nominal distinction.)

Quote
Without the Nipping Helix, ...
And here I want to push back against the helix aspect
of the "central nipping loop", because it is a helix
of necessity rather than *ideal* (one might be able to
avoid this by reeving through hollow braided rope!),
and should the helix open much,
then I don't like classifying it as a "bowline" --though
I have pointed out that quite obvious #1010 bowlines
have lost their essence in this way, into "pile-hitch
nooses"
!  --a matter of force, & transformation.
<sigh>

But, really, I have AIMED for stabilizing a rather open
helix, and don't find it quite so "nipping" as a loop,
for, being open, there isn't the compression of one
side vs an opposite.
Would that things were black'n'white, present or not,
but ... such is life/knots.

Back to the top point, though :: what is it we want from
our nomenclature?  Yours seems to give us so little in
denotation, almost no collection; mine reaches to a group
of "like" knots, and maybe by a Xarax rule they are further
constrained to be PET?!  And then the water bowline
maybe gets in with some relaxation of pure "nipping turn",
and the "cloverhand bowline" has *attachment*/proximity
to this grouping though it's not PET ("cloverhand" being an
overhandoriented to resemble the clove h.; and
which for the eye knot seems to offer some slack-security
and nice curving of the SPart).

--dl*
====
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 31, 2018, 12:03:02 AM
per yChan:
Quote
They are in this post :
Reply #370 para.6 and Rely # 374 second last para.

Thank you yChan. I appreciate that you have taken the time to look into this issue of 'TIB'.
I went back and closely read what I wrote.
You have applied an incorrect interpretation of what I wrote (sorry).

If you read it again (more carefully) - you will see that the reference to 'TIB' is in direct relation to the nipping structure.
I did not declare the entire knot to be TIB.

I would like to emphasize (for the record) - that it is a conditional requirement that all 'Bowlines' have a nipping structure that is 'TIB'.
There are other conditions that also apply - TIB is just one of them.

May I make a request from you please?
Can you go back and delete your posts which allege that I stated that #1033 Carrick 'loop' is TIB?
Then I can delete my specific replies.
This will tidy up this thread so there are not unnecessary posts adding clutter.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on August 31, 2018, 01:38:11 AM
from Derek:
Quote
Once we have formulated a definition that works for The Bowline (#1010), and can be seen to work for the knot at work - 'in the wild', then we have a tool that will allow us to understand how the Bowline works

Not surprisingly, others have already advanced a working definition that permits certain knot structures to be awarded the title of 'Bowline'.
The primary Bowlines had been illustrated by Ashley at #1010, #1012, #1013, #1034 1/2, #1072, #1074, #1080, #1087 in 1944. There is universal agreement that #1010 is a Bowline (ie it is the 'standard' or 'common' Bowline).
All of these structures share the same fundamental structural components.

Quote
In taking that step we give ourselves the opportunity of seeing  what other (self evidently NOT Bowlines) are let into the classification, thereby destroying any value to the definition.

Having trouble with interpreting your intended meaning with this last (italicized) statement.
Did you mean; "so as not to disturb or set aside the meaning of 'Bowline" ?

Or, did you mean;
"In taking that step, we give ourselves the opportunity to exclude knot structures that do not meet the definition of a 'Bowline' - so as not to destroy or dilute that definition".  ??
Can you clarify?

Destroying the value of [a] definition that defines a 'Bowline' could only occur if that definition was flawed to begin with.
But I do understand your point... we need to first arrive at a definition that is correct (or as accurate as can be).

I have difficulty with your requirement that the onus of proof is reversed - re your comment that:
Quote
For me, Ashley puts forward the ideal set of descriptors.  I believe to use any other lexicon, it would be first necessary to produce a case which faults the Ashley statements

I believe that reversing the onus of proof would have the effect of restricting and narrowing future opportunities to re-examine old concepts and hinder innovation and creativity. And, it could provide a convenient excuse for closing ones mind to new ideas.

I see parallels with the definition of a 'loop'. G Budworth and B Toss appear to differ in their conceptualization of a 'loop' compared to C Ashley. H Asher strongly implied that a 'loop' can have S or Z chirality (and so did Brion Toss - although he phrased it as clockwise / anti-clockwise). C Ashley appears to have overlooked chirality.
Therefore, a 'bight' cannot have any particular chirality - that is, a 'bight' cannot have an S or Z form; only a 'loop' can have this property.

Budworth, Toss and Asher all came from a later era than C Ashley - and have attempted to shed new light on knots and knotting.

The nipping structure of [a] 'Bowline' is essentially formed first - and then all remaining maneuvers of the 'working end' feed through it and around it to complete the 'Bowline'.
The nipping structure is the fundamental reason why all 'Bowlines' are resistant to jamming (because it is 'TIB' and therefore topologically equivalent to the 'unknot' - as well as being freely able to encircle and clamp both legs of the collar).
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alanleeknots on September 03, 2018, 01:15:47 AM
Hi All,
Many years ago I create this knot here, at that time still very green, not so sure, I didn't post it to the forum.
has been sitting in my unfinished work folder since then.
Now have a look at it again, I found it no a bad loop at all, nice looking, look like bowline, have a bowline nipping loop,
like bowline's collar. but the tail didn't go back to the nipping loop.
So what it belongs?  謝謝 alanleeknots.

Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on September 03, 2018, 01:58:54 AM
Thanks for presenting this creation Alan :)

Yes - it does have a nipping structure that takes the form of a helix/loop that is loaded at both ends, 'TB' and jam resistant.
However, as you have already pointed out, "The tail didn't go back through the nipping loop"

This would rule it out from being awarded the title of any class of 'Bowline' (either primary Bowline, virtual Bowline, or anti-Bowline).
The collar (aka 'Bight Collar') has 2 legs, and both of these 'legs' must be fully encircled and clamped by the nipping structure.
Since one of the legs is outside of the nipping structure and isn't clamped by it - it is excluded from being identified as a 'Bowline'.

It should be possible to work on this structure to improve its resistance to ring loading - and maybe devise an alternate geometry so that the nipping structure can encircle and clamp both legs of the collar.
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: alanleeknots on September 04, 2018, 09:21:09 AM
Hi All,
Mark thanks for your reply .I know it is not a pure bowline, that's why I ask "what is this knot belong"
This knot does have a bowline nipping loop and nip on one eye leg, Not so sure, do this knot qualify for half bowline.

Quote
and maybe devise an alternate geometry so that the nipping structure can encircle and clamp both legs of the collar.
offer little more secure on the tail. Even though I am too fancy about it, we don't need any change or modify here.
It's just another valid knot that does exist in the knot land, If I make any change on this knot "Knot God" may not forgive me.
謝謝 alanleeknots
Title: Re: What defines a Bowline? - structure, characteristics, topology
Post by: agent_smith on September 26, 2018, 02:15:36 AM
Some more work I have been doing in the lead up to the next (updated) version of my 'Bowlines Analysis' paper...

I had advanced that all 'Bowlines' can be classified according to the geometry of their nipping component.
The term 'nipping component' has a strict definition.

1. It is topologically equivalent to the 'unknot'
2. It is TIB (Tiable In the Bight) - which relates to #1 above
3. It is loaded at both ends
4. It fully encircles and clamps both legs of the 'collar'
5. In the primary Bowlines, it takes the form of a helix or twin helix
6. The compression force exerted by the nipping component is directly proportional to the load
7. It exists between the SPart and the ongoing eye leg
8. It has a particular chirality - which may be S or Z form.

The nipping component is fundamental to all 'Bowlines'.
All initial tying maneuvers feed through the nipping component - indeed, it is formed first to allow all subsequent maneuvers to be made.
The jam resistance of all Bowlines is closely related to the function of the nipping component.