Analysis of Bowlines paper uploaded for review and comment (PACI website)

Knotting Concepts & Explorations
281

Here it should be noted that merely counting the number
of diameters surrounded does NOT solely determine sharpness
–e.g., were those diameters in a row (or, as one can find sometimes,
the initially contacted first two–, the turn would be a 1dia turn (think
of running a line down along a row of trees and turing around the
last in the row).
And, while to some simple degree --a bit above “simplisitic”–,
more diameters are better, rounder, there is also the matter
of shape. I recall seeing a photo of an Instrom(?) test device’s
rope-receiving anchor : it has a diminishing-radius bend for
the line to curve around; one can simulate such curvature
sometimes in a knot. (And one can remark that such careful
tweaking is matter not of practical concern but only for those
keen to understand knot mechanics!)

... the [i]Fig 8[/i] where the loaded line executes several partial turns, gradually transferring force in the process.
Let me suggest that this knot (by which we mean the eye knot, usually) benefits from the compression around the S.Part from the turns of the eye legs, before the S.Part makes its U-turn around them.
Indeed, Dan does hold that the 'Key' component of the Bowline is the nipping loop, However, how he manages to argue that, in a two component knot, either of the two components is more 'key' than the other, I do not know.
?! You're confusing "key" with "defining". Yes, somehow one must stabilize a [please note exact typing >>>] "turNip" [<-one capital only!], but IMO it is the principal engagement of this structure that characterizes [i]*bowlines*[/i]. And so I include the [i]Myrtle[/i], and also become aware/bothered by the fuzzy boundary of the central nipping loop (aka "turNip"), as it goes from minimal to greater helix --at some undefinable point one doesn't want to call it a "loop", but ... .
the Turnip
Understand my cutesie term's origin : my game of letter-fusing of adjacent words, where shared letters are imaginatively run together and so rise from lowercase in each to uppercase in the fusion :: 'turn' ><'nip' >'turn''nip'< >>'turNip'<< ("whaTHEck?" you say?!) ;D
' When is an Eye not an Eye? Answer - When it is a loop...'
The eye is a functional aspect of the knot --what classifies it among other kinds/types/classes of knot. And the "eye" is indeed adopted because "eye splice" is universally understood, and "loop" is SOO overloaded with competing senses --better to stay clear. ("loop" and "bight" compete, e.g..)
while all Eyes are loops,
NOT if you follow many knot-books' defining "loop" as a 360-degree turn (a circular thing), which many do in distinction from "bight".

This is a tricky area, and X. of course wanted such
distinction to make the sheet bend have no loop
but a “hitch”. One might reflect on these similarly
shaped knots and wonder how much of that “ongoing
eye leg” contributes to the ability of the turNip to nip
–something, e.g., one might think is done (variously
well per material & foreces) in the sheet bend
(or in the water bowline which has that clove hitch
crossing part between arguable turNips though it can be
challenged how much action comes via it!

I would agree with you on this one were it not for the fact that a nipping loop does not have to be externally loaded on both ends in order to function. For a nipping loop to function, all that is required is for one end to be secured, the round turn frictional amplification is then sufficient to transfer the applied load into the nipped core.
Well, I've echoed, reiterated, concurred in this point.

–dl*

282
Quote 
I would agree with you on this one were it not for the fact that a nipping loop does not have to be externally loaded on both ends in order to function.  For a nipping loop to function, all that is required is for one end to be secured, the round turn frictional amplification is then sufficient to transfer the applied load into the nipped core.

Well, I’ve echoed, reiterated, concurred in this point.

–dl*
====

I had the distinct impression that Xarax required both ends of the nipping loop (ie a closed helix structure) to be loaded - and this requirement narrows the range of knots that could fit within the definition of a Bowline. Xarax also required a collar structure (which acts as a ‘capstan’ to a certain extent). Therefore, the presence of a nipping loop and a collar structure is what enables a structure to be classified as a Bowline.

Where this gets murky - in my view - is when we start to examine more complex nipping loops (nipping structures).

For example, the so-called ‘Karash loop’ has a nipping structure based on a crossing/munter hitch. The question for me is whether the munter hitch component actually functions as a nipping structure. That is, is it loaded at both ends and does it create a compression zone? There is indeed a collar structure… so it is down to the nipping structure.

And then there are the double nipping loops as with #1013 (Double Bowline) - again, both ends are loaded and there is a compression zone. There is also a collar structure. So #1013 is definitely a Bowline.

In my new and revised Bowline Analysis paper - I will be attempting to arrange and classify Bowlines based on their nipping structures..eg;
single nipping loop based on a closed helix
double nipping loops based on a closed helix
crossing/munter hitch
overlapped double nipping loops (as with #1012)
and so on…

283

I am starting to get quite worried here.

Not only has Constant not waded in on this discussion, but you are all talking about him in the past tense.

What has happened?

Derek

284

He is alive and well…but for reasons unknown to me, he no longer visits the IGKT forum.

Xarax is a passionate man - and he certainly pushed out the IGKT horizon further than most.

His theories on knots and in particular - Bowlines - broke new ground.

You either loved or disliked him - and whichever camp you were in, you would have to admit that he did make significant contributions to our understanding of knots.

…

It would be good to get a summary of his position re the structure and definition of a Bowline… seeking clarification on his theories about the following:

  1. The collar structure and the ‘capstan effect’ created as the collar performs a U turn around the SPart (I recall Xarax adding a pulley substitute for the SPart to illustrate his theory)
  2. The ‘proper’ collar (what exactly did Xarax mean by this?)?
  3. The nipping loop loaded at both ends (and not just one end) - a few things come to mind here… this narrows the range of eye knots that could be classified as belonging to the Bowline family (which is better than a wider definition in my opinion). It also makes the definition of a nipping loop stricter. Need verification of Xarax’s position on this.
  4. The nipping loop and its compression zone contained within the helix. Need further expansion on this.
  5. Complex nipping structures such as the ‘Karash double eye knot’ - per Mike Karash - instead of a simple helix it is now a more complex crossing/munter hitch - does this still fall within the definition of a nipping loop according to Xarax?
  6. Tight radius turns and pathways - forcing the working end to wind around single rope diameters/cross-sections - instead of more gentle curvatures - what is his views on this (although this one is not Bowline specific)?
  7. Anti-Bowlines - what is Xarax’s position on this? - ie Where the collar does not form around the SPart but, instead, forms around the returning eye leg. And according to Xarax - there are 4 anti-Bowline structures (chirality?). And is he in support of the ‘anti-Bowline’ term?
  8. The nipping structure of #1012 (water Bowline) - I see this as 2 nipping loops functioning as a clove hitch (when united) but which can also be spread apart to break the clove hitch structure and instead function as 2 independent nipping loops - symmetry breaking?? And a Bowline based on a ‘constrictor hitch’ nipping structure - I see this as 2 interlinked nipping loops - but in this case, the nipping loops cannot be separated. I think Xarax and Dan debated these structures at length…but what was the outcome?

I would like some very clear and very concise (ie clarity) on these points.

Edited: Grammar corrections and added further points

285

[quote author=agent_smith link=topic=4480.msg37977#msg37977 date=1451803432]

Quote 
I would agree with you on this one were it not for the fact that a nipping loop does not have to be externally loaded on both ends in order to function.  For a nipping loop to function, all that is required is for one end to be secured, the round turn frictional amplification is then sufficient to transfer the applied load into the nipped core.

Well, I’ve echoed, reiterated, concurred in this point.

–dl*

I had the distinct impression that Xarax required both ends of the nipping loop (ie a closed helix structure) to be loaded - and this requirement narrows the range of knots that could fit within the definition of a Bowline. Xarax also required a collar structure (which acts as a ‘capstan’ to a certain extent). Therefore, the presence of a nipping loop and a collar structure is what enables a structure to be classified as a Bowline.


As noted above, X’s position wasn’t everyonElse’s --did you
miss my remarks about his rejection of the sheet bend
as having a nipping loop (something he I think began mostly
challenging Derek about, ad nauseam)?! My point to this
comparison was to show --concurring w/Derek’s view–
that the apparent “loop” can be effected, can exist,
without its continuation being loaded --it might be a free
tail! And where it somewhat IS loaded, that loading can
vary by quite some amount, it would seem, enough to
raise the question of making its loading a criterion.
But there is some appeal for that, still … .
(And one can think that although there might not be
such extended loading of it where it is the crossing
part of a clove-/cow-hitch-like component (e.g. water
bowline).

I’m reminded that I choose to take a view of what is
a noose based on purely apparent structure
irrespective of behavior --which behavior can be so
contingent upon materials & forces : I don’t want
knots to be jumping from one class to another based
on a change of materials! (Now, in more practical
vs. theoretical terms, I would treat “noose” in the
way it’s commonly understood, and where just such
particular, sliding-until-tightly-closed behavior occurs.)

For example, the so-called 'Karash loop' has a nipping structure based on a crossing/munter hitch. The question for me is whether the munter hitch component actually functions as a nipping structure. That is, is it loaded at both ends and does it create a compression zone? There is indeed a collar structure... so it is down to the nipping structure.
Here I disagree (but "feel your pain") : I see that very [i]crossing-knot[/i] structure to have a collar(-ing effect) --the S.Part bears into the turn around it, after all. It certainly functions to nip : the knot wouldn't hold the "proper collar" otherwise! (Mind, I don't give a hoot about having this particular propriety, but ... .)
And then there are the double nipping loops as with #1013 (Double Bowline) - again, both ends are loaded and there is a compression zone. There is also a collar structure. So #1013 is definitely a Bowline.
One can question how much such a [u]coil[/u] is related to the [i]turNip[/i] --examining the forces along the strand, and so on. But if that isn't part of the group, then woe be unto us; but we've gone beyond the 360degree turn, now --as with the [i]mirrored & water bowlines[/i] not seeing the nipping turn's "end" lead (directly) into the eye.

One might consider Ashley’s #1016 --which I’m thinking
is one of the many knotting mistakes echoed for ages–,
which concludes with a knot whose apparent turNip
is loaded on one end only, the other held in resistance.
(But consider #1074, at which there is explicit rationale
given for the cryptic advice of the former (and #1882)
–whose images and final knots contradict the advice
(for “double bearing”) !! Methinks Ashely quite sloppy,
in this, alas.)

As for

you would have to admit that he did make significant contributions to our understanding of knots.
I can agree with "significant" if only measured by volume (as in "quantity" not "noise").

–dl*

286

I have a simple response to the proposed requirement that both ends of the turNip (attention to the capitalisation noted Dan) must be loaded.

Make a Bowline. Then load only the SP and collar loop leg.

The knot holds perfectly without any loading being applied to the turNip loop leg.

It holds perfectly, because the structure has morphed slightly into a perfect Sheetbend.

For me, this is a simple and perfect example that the Bowline is a Sheetbend with its turNip end connected up to form a loop.

May I presume that we all agree that this has not ceased being a Bowline?

As for what Constant meant, I can only say that there was little of his perspective on the Bowline that I agreed with, but in his absence, all I can do is reiterate my own understanding on the components and functionality of this knot.

NB For those adventurous souls amongst us that immediately went and tried the Eskimo Bowline, you will have morphed its configuration into a single (or half) Carrick bend / loop knot. Either way, you will have demonstrated that both ends of the turNip do NOT have to be loaded.

Derek

287

You know Dan.

#1016 conforms nicely with my first definition of a Bowline i.e. it has the Sheetbend core (SbC), it has the turNip and a functional colar (well two actually). It also wonderfully demonstrates the point that the turNip can have an unloaded end and still function perfectly.

http://igkt.net/sm/index.php?action=dlattach;topic=5593.0;attach=20267;image

Although Ashley shows the spare loop tidied up, it can just as easily be left floating (as per the middle diagram) and the turNip performs exactly as it does in the Sheetbend - one ended.

But this knot also demonstrates another aspect of knot design - overdoing one advantage and loosing another.

This little knot has four diameters tracing through its nip, so it should be nice and strong…

But, all these cords are sharing the nipping force between them and weakening the grip on the collar end.

Loading just the collar loop leg and the SP in my ‘twiddling’ polyester braid, and the leg pulls through the nip, around the collar and pulls the end through the nip.

In hairy hemp it might have been usable, but in today’s cordage it deserves a skull and crossbones.

Of course, this knot would be virtually useless to Mark as a tie in, because the loop is folded from a bight.

Derek

288
For me, this is a simple and perfect example that the Bowline is a Sheetbend with its turNip end connected up to form a loop.

May I presume that we all agree that this has not ceased being a Bowline?

The Bowline and the Sheet bend are 2 different species. One does not morph into the other merely on account of how it is loaded. Holding the SPart in one hand and the ‘returning eye leg’ in the other (and then pulling) replicates the functional aspect of a sheet bend - but it does not alter the fact that it is still a Bowline.

If Xarax required both ends of the nipping loop to be loaded - I concur. And not because I am parroting him - but, because it makes sense from a structural point-of-view. It also serves to narrow the definition of which knots could be classified as belonging to the Bowline family. Note there are many on the IGKT forum who dislike the way the definition of a Bowline has progressed - citing that “virtually any eye knot could be classified as a Bowline”… So I am in favour of narrowing the definition, rather than widening it.

Dan indicate that he debated with Xarax at length on the structure of a Sheet Bend…? And that Xarax also disagreed with Derek re the function of Sheet Bend core…? Well, I concur with Xarax that there is no ‘nipping loop’ component in a Sheet Bend. Oh dear - what I have I done?

I think this comes down to the definition of a nipping loop.

What is the strict definition of a ‘nipping loop’?

In my view, for a structure to be regarded as a ‘nipping loop’, the following criteria must be met:

  1. There nipping loop must take the form of a helix or have a helical structure; and
  2. Both ends of the nipping loop must be loaded; and
  3. There must be a compression zone within the helical structure - so that the compressive force scales according to the load applied at each end (there is actually a mathematical formula here - as load on each end increases, there is a corresponding increase in the compressive force. If only one end is loaded - the compressive force within the helix would not scale at the same rate or magnitude).
For those adventurous souls amongst us that immediately went and tried the Eskimo Bowline, you will have morphed its configuration into a single (or half) Carrick bend / loop knot

If an ‘Anti-Bowline’ is tied - simply ring load the eye. This will demonstrate the functional aspect of a Sheet Bend core too - and also show how anti-bowlines are resistant to ring loading. Although there are 4 different forms of the Anti-bowline - depending on which one you tied would orient the ‘tails’ accordingly. But it is still an anti-bowline - not a Sheet Bend.

…

In my view, with a Sheet Bend - it is the SPart that crushes its own ongoing tail. As the magnitude of the force increases, the crushing force of the SPart scales accordingly and acts to trap the tail and prevent further slippage. The ‘collar’ structure provides a framework to stabilise and contain the SPart and its own ongoing tail.

I can feel another debate coming…

289

I quite disagree : this comes to the heart of the philosophical,
definitional question What is a knot?! --and IMO the
most important thing (at least for theorists) is the geometry
and loading of it. (And one can point to the vulnerability of
the bowline (per #1010 orientation) to ring-loading just
as a case : the once eyeknot b. is effectively then the end-2-end
knot wrong-way Lapp bend --which can spill! I would
certainly not say, from a theorist’s perspective, that "it’s still
a bowline; but, OTOH, from a practical perspective one
is naturally inclined to say "The bowline can spill if it’s
ring-loaded --and not the awkward “The b. can become
a <diff. knot which …>” !)

But, here, in debating/seeking what a nipping loop is, one
shouldn’t change loading as though it’s of no consequence.

Note there are many on the IGKT forum who dislike the way the definition of a Bowline has progressed - citing that "virtually any eye knot could be classified as a Bowline"
?! Let's see how this "anything" has grown? To my awareness, it's been less open than natural naming has put it. But there are tricky cases, to be sure. I'm just not getting the feeling that "anything" has been an issue --just that drawing fine boundaries has been!
Dan indicate that he debated with Xarax at length on the structure of a Sheet Bend....?
X. seemed to take pleasure in ranting his views, and favorites were how no one understood that the [i]sheet bend & bowline[/i] were NOT related, and his all-time favorite that the "so-called, falls Zeppelin loop" was in no way a Z., ad nauseam! My reply was that at least the structure in the first case and the common way of relating/forming eye-knots from end-2-end knots in both, DID so relate them (though the mechanics necessarily changed). --to which I then pointed to a different way to relate end-2-end knots & eye knots.
Well, I concur with Xarax that there is no 'nipping loop' component in a Sheet Bend. Oh dear - what I have I done?
I'm sympathetic to this view --and you can win at least in the "apparent"ness of it--; but my point was that the actual amount of contributing, effective force got by loading difference might be trivial, and varied over much range. (If the SPart-side loading is arrested in the end-2-end knot by the pinch at the crossing point, one can question how the loading of the continuation into the eye leg (for the eye knot) can be so important --that's the rub.)
I think this comes down to the definition of a nipping loop.
Yes, I take the #1010 as the canonical paradigm. (But recall that in HMPE cordage this [i]turNip[/i] becomes a rolling circle --a [u]rubbing[/u] loop!)
What is the strict definition of a 'nipping loop'? 3. There must be a compression zone within the helical structure
I'd not use the notion of "helix", since the ideal is a circle, and practical circumstances keep us from that --but let's not so much acknowledge the slippery slope! We (or I, anyway) do have to face the facts of that aspect --does a capsizing [i]bowline[/i] cease its prestigious membership in the Bowline Club ... at what point, exactly ?! My "anti-bowlines" have usually a more immediate challenge to resist helixness.
there are 4 different forms of the Anti-bowline
You said this before : please enumerate [u]your[/u] four. (I'm thinking of an unbounded set, but maybe I'm too lazy to see where the fences should go.)
In my view, with a Sheet Bend - it is the SPart that crushes its own [u]ongoing tail[/u]. As the magnitude of the force increases, the crushing force of the SPart scales accordingly and acts to trap the tail and prevent further slippage. The 'collar' structure provides a framework to stabilise and [i]contain [/i]the SPart and its own ongoing tail.
Here you show a trouble w/definitions, as I mentioned above (about when a bowline is/isn't) : whatever is "ongoing" with this "tail"?! --those are opposed concepts (or redundant)! ::) The "wrong/opposite-sided" [i]sheet bend[/i] tends to draw up in a more round geometry, more resembling the [i]bowline's[/i]; and the "left-handed" [i]bowline[/i] puts more pinching pressure, I think, where the SPart nips its tail (at which point it's not very "ongoing" but "herestopping"). ;)

But, as per my thoughts on “noose”, I can be swayed
to your side of the debate --what I’ve been calling
“apparent” so as to avoid trickiness of actual forces.
And I don’t think that we’ve all so much “anything goes”
in this; except that we do show (and can show more)
many knots not considered in the literature.

My locktight loop --a sort of extended Karash structure
(just a single eye)-- is a good knot to consider here for
treatment; it has X.'s “proper collar” (as well as some
slightly different ones), but makes a away-from-eye
wrapping back to the fold-around-SPart & “ongoing”
into eye flow --thereby giving less collaring effect
than w/o those wraps. But … !?

Again, re #1016, do consider its text and that for #1074:
IMO, that latter is correctly presented --image matches
rationale–, and the former, also with its echo #1882,
is simply lazily, wrongly (incompletely) presented. It
serves a purpose in our deliberations (and esp. with
the one potential eye drawn snug to the body,
where it will give at least resistance to force
unlike the tail of a sheet bend).
–dl*

290

ABOK #1016 is close cousin to the “clip two” or “in-line bowline” (ABoK #1074 "bowline with a bight. Where the working bight and standing loop are formed to be of equal size and form an eye composed of two loops. [1]

I would say that clearly #1016 is not a bowline, but the “clip two” bowline is a bowline. I make that distinction based primarily on gut reaction (more on that in a moment) but digging deeper the difference between the two is which loop(s) are loaded. So I would say that one (perhaps obvious) defining feature of a bowline is that the standing loop is loaded.

As far as defining “bowliness”. I agree that a nipping loop, collar, and standing loop (standing as in it’s fixed, won’t slip like a noose) are three ingredients to a bowline. However, a knot could possess all ingredients and still not be a bowline. An example:

Dan Lehman examined #1033 (Carrick loop) - to see if it would fit the definition of a Bowline. #1033 has a collar structure and it has a nipping loop that is loaded at both ends. The source of one end is the SPart and the source of the other end is the ongoing eye leg. There is also a collar structure.

This in my view fulfills the definition of a ‘Bowline’.

I disagree. I don’t think #1033 is a bowline.

It may be hard to nail down exactly what defines “bowliness” but I know it when I see it.

#1035 is another knot, similar to a bowline, has the three ingredients, but isn’t a bowline. Or the eskimo bowline, not a bowline, but has the ingredients.

So perhaps there is a missing ingredient in the definition, and group discussion may through consensus, eventually (at least for us) define all the necessary ingredients of a bowline… but I would as a healthy dose of the “I know it when I see it” standard as a way of not getting too carried away with:

... include every loop knot that contains a nipping turn into a giant family of Bowline-esque knots

I agree with Mark that “eye” knot is a useful and descriptive definition. I also agree that “eye” defines an idea that is independent of scale… a very large circmfrance eye is still and eye IMO. I agree that “loop” is a term that has some ambiguity (perhaps through sloppy use in knotting literature). Using #1074 to illustrate the difference between “loop” and “eye”, with #1074 you have a two loop knot, but only when the two loops are dressed evenly and loaded together do you have an “eye” structure.

cheers
andy

[1] the photo is from Rick Lipke’s Technical Rescue Riggers Guide

291

Thank you Mark, we have made considerable progress.

Let us put aside any thoughts of the SbC, it has served its purpose in bringing you to the conclusion that a Bowline loaded only on its SP and its Collar loop leg, leaving the ongoing turNip loop leg unloaded - is still a Bowline.

And there in its simplicity, we have it - the imposed definition that the turNip component must be loaded on both ends in the Bowline, is nothing more than an imagined constraint. Nothing more than a point which could generate many hours of enjoyable (for some) argument.

It is worth stating it again - The Bowline is still a Bowline even if it’s ongoing turNip loop leg is unloaded - if we accept this, then we must accept that the turNip component in the Bowline does NOT have to be loaded on both ends.

The turNip is able to express its compressive force even if one end is only clamped.

And no, you do not now need to accept every knot which has a turNip component (double end loaded or clamped loaded) into a hypothetically constructed ‘Bowline Family’, it is a meaningless naming exercise. Meaningless as me now suggesting that we bin the name Bowline and instead call it the Sheetbend Loop Knot, just as we might join up the ends of a Carrick bend and call it the Carrick Loop Knot…

The only familial action going on in our world of knots is that of shared components and shared utilisation of components.

292

Hi Andy,

Your approach is important and whenever we ‘feel’ that a knot is or isn’t a member of a certain group, we should perhaps stand back and ask ‘what is driving that intuition?’.

In the case of the two knots you cite, #1035 and the Eskimo, they are both based on the same two components - the Nipping Loop Component (turNip), and variants of the Carrick Component (the collar being a sub component of the Carrick Component). So, from a component perspective, these are both Carrick Loops, not Sheetbend Loops.

Perhaps we could start mapping knots into shared component groups?

Derek

293

If I’m reading this correctly, this assertion means that a sheetbend is a bowline. I cannot agree. A sheetbend is different from bowline. Therefore a nipping turn must be loaded on both ends.

I’m not sure what one would call the helical turn part of a sheetbend though if not a nipping turn.

294

Andy, how can a Sheetbend be a Bowline? The Sheetbend is a bend, but the Bowline is a loop knot. As you conclude - they are different. But the difference is not in the core, it comes from how the core is wired up.

And if you insist that a nipping turn must be loaded on both ends, then what has happened to the Bowline that has got snagged up so that all the load is on the returngoing loop leg and nothing on the outgoing loop leg? Has it stopped being a Bowline just because the nipping loop is no longer loaded on both ends?

However, you are right in part, because the turNip in both these cases is loaded both ends, but the loading on one of the ends is caused by being clamped internally, so load translates around the nip to the inner point of the trapped end, so indeed it is loaded, but only internally. I think that is likely to be as clear as mud… Sorry.

295

[I’m greatly annoyed that a prior attempt to reply
lost text via an unrealized excessive highlighting and
then --poof–, lost to a keystroke w/o awareness until
too late to control-Z recover. CURSES >:( >:( >:(
]

As I must’ve previously stressed,
this goes right to the point of what IS a knot?!
This is a profound, philosophical/definitional consideration,
not one with an answer waiting to be found outside of
ourselves by empirical examination.

Certainly in some situations, it will make sense to say
the things quoted above --i.e., “still a bowline”–,
where considerations of the vulnerability of that eye knot
to ring-loading or --for the particular loading described–
imbalanced loading that might arise e.g. where a dock
line’s eye makes a full/round turn around a pile and upon
the drifting/shifting angle of incidence one leg goes slack
and the other takes all the force.

But it is equally likely that for the purposes of defining knot
that one adopts a position in which that entity is described
by an entanglement and loading profile --and change the latter
(as is the case here), you change the knot! And you change
how you have to speak of things, too, which becomes awkward.
One can define an “eye knot” to be an entanglement of two
pieces of material (so, four ends) where a one end of piece
A is loaded in opposition to its other end and one end of the
other piece, whose remaining end is unloaded. (And note that
this allows that the opposing ends to not actually join to form
. . . an . . . “eye” --well, that challenges that class name, huh! :smiley:
But so far as the “nub” feels, that connection-or-not is irrelevant,
so long as the loading profile obtains. --by one purpose of defining.
(I’ve conjured the image of a long tow line tied to starboard cleat
of a barge and then a short compatible line from the port cleat is
tied into the other, forming a . . . bowline --by loading profile,
at least. (Here, one could argue that the barge essentially completes
the “eye”, but … .)

Here’s an exercise, which works better or worse depending on how
frictive your cordage is --surely slipping in HMPE, but holding in most–:
tie the water bowline /mirrored bowline and then pull out a good bit
of the connecting span of the base clove/larkshead structure
–which will result in sheet bend mechanics at those two
(primary & secondary) turNips. And then muse over whether
you have yet a “bowline” or something other. Well, my real point
to this exercise was to show that that “ongoing” part --which is the
crossing part in the just-cited knots-- isn’t necessarily all so loaded,
or delivering load into the turNip (if it can be, as is seen in this
experiment, not be needed for the turNip to hold). The loading or mere
in-place passive resistance will have some influence on the roundness
of the turNip, though.
But you see how forces and so on are coming here in degrees,
not happily in some black-vs-white clear delineation of things
–that’s my assertion.
And why I might lean toward appearances, a sort of nominal
loading of both turNip ends.

To The Dunnyman, how do you discriminate the U-turning and leg-nipping
part of the fig.8 eyeknot? Surely, going beyond this area one can
point to its doing this & that. It is possible by careful positioning
of the “ongoing” end of the nub to also isolate a lose arc of material
to render the S.Part in a sheet-bend-like form, the returning
eye leg making a bowlinesque “proper collar” to keep things intact!
–have we then (only then?) a “turNip”/nipping loop?
Not by “appearances”.

But this is problematic.

Meaningless as me now suggesting that we bin the name "Bowline "and instead call it the "Sheetbend Loop Knot", ...
Ha, do realize that in this you have ignored the former end-2-end knot's asymmetry --that it might be, of it, that the other side's tail becomes the "ongoing leg" (not very well, agreed)! Which is sometimes named the "crabber's eye"?
It is worth stating it again - The Bowline is still a Bowline even if it's ongoing turNip loop leg is [b]unloaded[/b] - if we accept this, then we must accept that the turNip component in the Bowline does NOT have to be loaded on both ends.

The turNip is able to express its compressive force even if one end is only clamped.


Here one must ask : what (then) makes this cited
component “the turNip” ?!
–and my appearances can answer that?!

Still, I feel some angst about moving away from at least
some even slight contribution to the “compressive force”
–even one more imagined per appearances than actual!
For, in the Beginning, that was how this structure got
found : that the wonderfully simple & efficient bowline
is just the marriage of a bight & loop (aka “nipping loop”…)!

… and then we began the slippery exploration of a slope …

And no, you do not now need to accept every knot [that] has a turNip component (double end loaded or clamped loaded) into a hypothetically constructed 'Bowline Family', it is a meaningless naming exercise. ... just as we might join up the ends of a [i]Carrick bend[/i] and call it the "Carrick Loop Knot"...
How did this all of a sudden become "...meaningless..."?! Just a second ago we were in the rigors of definition, and then --pooph!-- we engage our checklist but find the result devoid of meaning?

Here I think we can see something resulting from losing
the appearance of the turNip by reference to actual forces
–to material aspects. (–as one might have to change
classification of a “noose” depending on how well the darned
hitch-to-SPart slides or not along that noose-structure SPart!
.:. That is a problem I try to avoid, at leas for knot-theory
definitions (but not to a potential rope user who wants a
(working, effective) “noose”, no.

–dl*

296

Of course, I challenge this. (Some things are hard to see.) :wink:
In some orientation, #1033 is the epitome of bowline
–so emphasizing, showing the nipping loop in effect
But one must not draw it up (don’t SS369 it!) but leave it
so that the loop stays a loop and not a crossing knot.
Done just so, the knot is perhaps most resistant to jamming?
The sort of collar of the S.Part flows into a collar of the
“ongoing eye leg” and … no jamming.

So this shows how setting/orientation can have influence;
as it would should your bowline be so loose as to enable
the (partial) capsizing into a near pile-hitch noose.

FYI, I’ve found/fiddled a <<maybe-it-could-be(called)-a-bowline>>
in which the collar-bight legs are both unloaded (not actively,
just in passive resistance, one), and the eye legs come into
the nub together, one making the turNip and the other
going along until … . It’s TIB, with sheet-bend workings
if “through loaded”. Anyway, it puts yet a further challenge
to these classifications.

–dl*

297

Before we go further, we should ask
What is the purpose of this ("bowline’) definition?

Because I feel that I’m waging a Right-or-Wrong debate
and that at least implies a basis for making judgements
–but what is it?

One might make “bowline” narrower and then resort
to “bowline-like”, or go the other way and need some
means to limit subsets of “bowline” if using a broad
definition, to get back to what the narrow one comprises.

In any case, though, I’m afraid that there will be ways
to muddy the waters --knots & dressings & … that put
a strain on the delineations.

–dl*

298

Three new posts from Dan, and one of them is a biggie.

I cleared my desk, loaded my pdf copy of ABoK, pulled three lengths of twiddling cord out in readiness, made a cup of tea, settled my greyhounds so as to be sure of an hour without interruption - and sat down to immerse myself in pure Lehmanese.

Dan, your prose is amazing - efficient, compact and convoluted - just like our knots.

As I read and expand the Lehmanese into Laymanese, while building the forms Dan describes with my twiddling cords, I have to realise that Dan and I are almost at the opposite ends of a knotting perspective. While I see knots as their elemental components, Dan sees knots as entities, yet at the end of an hour, he has (I think…) convinced me that the Fig 8 is but a pair of interlocking nipping loops (or are they half hitches?).

Dan’s perspective is of course, the right one. While knots are ‘bags of components’, they are at the same time, dynamic entities, shifting and responding to the forces they are translating.

Then Dan threw a curveball at me - The ‘Barge’ Bowline -

A loaded SP with a loaded lateral hitched into it.

For me, without question, this is the Bowline (it just contains a barge as part of the loop). Dan has managed to focus the essence away from the outer connections and back into the knot itself with an emphasis on how it manages loads on its various legs.

So what can we take from this?

Our naming conventions seem to have been arrived at by classifying a structure (sometimes even their tying method) with a particular (expected) loading profile. And this raises a new question - Are we right to continue (and extend) this anachronistic naming system? Now we are taking one aspect of this system (partial structure) and trying to wed other knots with these partial structures into a single name family.

This leads me to the conclusion that there are two audiences we need to consider.

The first is the Common Usage / Layman group, wedded to the historical names.
The second is the vanishingly small group of people interested in structure and workings of knots, who almost certainly need a new perspective and lexicon in order to clear out the clutter of history.

I belong to the latter group, but I feel this thread belongs to the former, and more importantly, it wishes to remain in it. Rather than being constructive, contact between the two appears to be antagonistic to both.

I am feeling therefore that it would be better for this thread if I withhold further component focus comments.

Derek

299
I am feeling therefore that it would be better for this thread if I withhold further component focus comments.

Derek

Please dont!

This is exactly what we need…

You know that history shows us that it is usually a few determined individuals that go on to make the big breakthroughs…

Often, the people that gave up never knew how close they were to success.

300

Mark, it is not a case of giving up. But a constructive thread can be ruined by excessive posting on what are effectively tangential issues.

I will happily continue to contribute from my component perspective for your analysis. You will have to decide for yourself when enough is enough.

Derek