Here are several replies to issues raised in the recent discussion.
0) "Unfortunately when I tightened the trucker's hitch on one side,
the highwayman's hitch capsized on the other side."
!! BINGO! Roo & I some decade? back raised the warning
about this vulnerability of the highwayman's hitch
--which was probably never used in reality, just in legend.
And I simply reversed the ins/outs of those first two bights.
1) "Where did you come across it?" "In my hands."
I've become captive again to knots fiddling and in
the process pulled a few old pages of slipi-free fiddlings
and --voila-- there is this knot., viz., #20000515m14:04 <--edit
(or something w/diff. day-time suffix).
2) "this simple variation transforms the value of this knot tremendously."
How so? You've read (and can here re-read) my notes
of problems with this knot. However, I'll share w/all
that on the above old sketch I've given the knot my
*stamp of glory* --a commercial fishing-boat stamp
(impressor?) that my (unseen by me) grandfather had.
I must've been impressed hy the sure feeling of the
nipping turn, yet unaware of the very turn's downside
vis-a-vis releasing.
3) It's a bird, it's a plane, no it's ... !
Is it a *hitch*?
Well, as Roo is emphasizing, and as I also remarked,
it is well possible for the knot's pulled release end to
render the knot a bellringer's (eye) knot --i.e., the
twisted initially place bight (of the SPart) will effect
a nip on the bight it encompasses just as a sheepshank's
turNip can do, and ... no release (unless one can haul
hard enough to pull out the nipped bight around the
object, which is not necessarily practical).
Given that this knot's SPart has a nipping turn,
it's fair enough to see it as an eye knot, even
though it is applied much like a hitch. (And,
one might consider the simple larkshead /
girth/cow hitch when loaded : to some degree
it's operating somewhat as a twin eye, although
there's scant *knotting* to cite, absent the object!
4) "NCE" : IMO, not to the point, where "object" is.
There are many well-known hitches to cordage
--all those "friction hitches" climbers tree/caves/rock
use.
5) "... cease to exist when the NCE (<-object) is removed ..."
By this reasoning, a groundline hitch, anchor bend,
& timber hitch are not hitches --SOMEthing remains,
bereft the object.
Now, Derek did further write "in its desired form",
which extends the issue into finer delineations.
It's a tricky thing to define. At least, for me, I exclude
the common round turn & 2 HHitches" as being a
"noose hitch" and among "nooses", which I classify NOT
by form purely irrespective of performance (as the latter
is materials/forces dependent.
6) "Hi Roo, is it cordage dependent? The cord I tied
it in simply fell away to nothing... I will try in something
with a bit more 'memory'. "
As I explained above, and repeated here, YMMV per
conditions. Esp. if one has out much rope , hanging,
and has hitched around something frictive (a handy
tree, e.g.). It isn't "memory" but firmness/stiffness
of the material, friction vs. the object, and force
upon the SPart (which might be just that of a lot
of hanging rope, waiting to be released).
But this discussion regards what remains after
(an incomplete) release; that with Derek regards
after physically (or mentally) removing the object.
THIS slip-free hitch (I think of it thusly, w/o getting
mired in philosophical points) can exist in full form
supporing a hook, e.g., with ample *EYES* --and
that of course puts '"hitch" out of the picture!
(Try it : replace a pile with a spar with a ring
to the same physical knot.)
7) "[A] Bowline made snug around a bar is no different
to a Bowline thrown over a bollard. ... they both would
retain their intended form after the removal of the object."
Here, too, one can find issues. Rockclimbers used to tie-in
with a "bowline on a coil" which could much seem like
a hitch, in the tying.
And one can snug a bowline pretty well to a relatively
large object and get significantly/practically different
loading provile --at equal angles of 120deg of SPart to
each eye leg, forces are equal, no longer the canonical
eye's 50% + 50% vs. 100%. Will an eye knot
behave in the same across the range of such angles?
I know that your point is different in a stricter sense
of "knot class", but this is an aspect of things that
can intrude into some definitional exercises!
--dl*
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