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

[knot rigger]

The Bowline is the King of Knots because it is strong, secure, and versatile, as kings should be.  And simple, as kings generally are.

- Brion Toss

This aspect of simplicity is certainly an ingredient in my definition of bowline.

1. A bowline forms a standing eye.
2. A bowline has a nipping turn
3. and a collar
4. and it?s simple to tie, use, and untie

Dan writes:

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

and Derek writes:

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.

Is the purpose of our bowline definition soley for Derek?s second group? Or perhaps is a definition stringent enough to satisfy the latter group useless to the former group?  As a member of both groups, I think there is middle ground, and merit in looking at the question of ?defining bowline? from both perspectives.   They are not antagonistic to each other, or mutually exclusive IMO.

Perhaps it would help to remember that a bowline is simple.  And to some degree, this simplicity is at the heart of it?s usefulness.

btw Derek, I believe ?clearing out the clutter of history? to be a fool?s errand.  By and large, the knots we have today, and the names of those knots are a messy product of messy history.  Live with it accept it, it?s not gonna change by decree of the IGKT (or any other way)

I think part of a solution that appeals to me regarding which knot is "bowline" and which isn?t, is the one Dan proposes

One might make "bowline" narrower and then resort
to "bowline-like",

A definition must have boundaries, it?s inhererant.  To me, to make a definition useful, it must be precise. A definition should provide some clarity, and too broad a definition doesn?t do this.  So my aproach would be to limit ?bowline? in certain meaningful concrete ways, and other knots that are similar but lye outside the delineations would be ?bowline like?

ok then

#1  A bowline is a knot with a fixed eye. 

This seems so obvious as to perhaps not need to be included, but it was pondering the difference between sheetbend and bowline that brought me to include it.  Axiomatically, a sheetbend is not a bowline, therefore the difference between the two should be included as part of the definition.  The fixed eye may be composed of one or two fixed loops. (maybe three)

#2 A bowline has a nipping turn.

I think we can all agree about this, but the devil seems to be in how to define nipping turn.

Mark writes:

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 ?

I would further limit (#1) as a nipping turn should have only a helix structure of one or two turns.  More than two turns isn?t simple.  And nipping structures that aren?t loops (helix) are near bowlines, but not bowlines (myrtle bowline, crossing turn nipping structure, etc)

I disagree that a nipping loop must be loaded on both ends.  I see this limitation as primarily a means of excluding the sheetbend from ?bowline?. I don?t think a nipping loop is exclusive to ?bowline? and I think a sheetbend has one.  The primary purpose and defining feature of a nipping loop is the act of compression.

#3 a bowline has a collar.

And I think it only has one collar.  More than one and it?s ?bowline like?

#4 a bowline is SIMPLE

Adding locking tucks to add security to a bowline is clearly part of what bowlines are in the 21st century, with all our slick and stiff modern cordage.  I?m not sure where to dawn the line, but I do think a line should be drawn when it comes to how many added locking tucks are two many for ?bowline?.  Perhaps two.  I would consider a double bowline with a yosimite finish and a lee?s lock a bowline, but to me this knot would be right on the line of what is ?bowline? and what is ?bowline like?  maybe two locking tucks it too many? Maybe it should be only one?  Certainly the resulting knot may not even be obvious that it?s a bowline at first glance.  Not obvious is not SIMPLE.


lastly, in reply to Dan:

Of course, I challenge this.  (Some things are hard to see.)   
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.

If I have to dress #1033 ?just so? it fails my SIMPLE criteria of ?bowline?.  I?ve played with this knot, looking for your bowline in there, but must not have your vision.


here is an attempt at a one sentence definition:

A bowline is a simple knot composed of one collar and not more than two nipping turns, which forms an eye composed of one or two fixed loops.


Lastly, Mark, good luck with the paper, looking forward to seeing it.

cheers
andy

[Dan_Lehman]

lastly, in reply to Dan:

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.

If I have to dress #1033 "just so", it fails my SIMPLE criteria of "bowline".
I've played with this knot, looking for your bowline in there,
but must not have your vision.

?!  You mean that you've been unable to preserve the knot's
loop --central nipping loop-- by relaxed dressing?!  Try better!

As for "just so", touche'.  But there is some of this even for
the common bowline --as my observations around some
trawlers of their 1-2"diameter docklines show (and as I've
shown in photos to this forum) : many knots that surely
originated as bowines have capsized into something not
so identifiable.  One can wonder about how "just so" would've
prevented this.  One can see photos in yachting magazines
where the collar seems (IMO) too loose and yet those knots
remain identifiably bowlines.  But the "just so" point
remains, and irrespective of one's particular "bowline" thoughts,
it points to issues regarding what is **a** "knot" and not
otherwise **anOTHER** knot --just variances in setting,
or in force delivered to same-set knots (those "initially bowlines"
dockline eye knots that became unidentifiable, variously).

here is an attempt at a one sentence definition:

A bowline is a simple knot composed of
 one collar and
 not more than two nipping turns,
 which forms an eye composed of one or two fixed loops.

So, no triple-eye "bowlines"?
Take a long bight (you don't see ends),
and by your preferred method, using the bight
as a "rope", tie a "bowline" :: this will have
doubled parts throughout because of working with a bight;
it will have 3 eyes, with its "tail" being a bight end.

"simple" seems a gratuitous --and dubious in being judgement--
part of your definition (remove it : what changes? ; replace it
with "complex" : what could that mean?).  I.e., by the rest
of your definition --which is more objective--, you pretty well
prescribe simplicity.
But methinks the mixing of subjective aspects or objective
constraints on size make for odd classifications; in which per
your definition one might wish to include the tugboat bowline
though by some objective criteria it doesn't qualify --but is
so *simple* & quickly tied (and an eye knot).


--dl*
====

[DerekSmith]

#3 a bowline has a collar.

cheers
andy

Andy, may I see if I can push you a little on #3

My contention is that #1010 has a Bight Component.  That is, it not only does it have a 180 degree collar, but the legs of that collar extend down and through the turNip.  These legs are critical to the knot in that they stabilise the turNip and allow loop force to be fed up into the collar, allowing a small degree of deflection of the incoming load before hitting the tight turns of the turNip.  Plus of course, one of these bight legs becomes the all important 'End' which is clamped within the turNip and so prevented from simply unravelling.

Ashley would call it the Closed Loop (#32) Component, but the point is that the collar by itself is almost valueless, while the collar plus its two legs are major aspects of this knot.  It is the collar plus the two legs that I call the Bight Component (BC)

Finally, in the spirit of 'Living with it', I am still sticking with Ashley's lovely depiction of a Bowline in #39 where he defines clearly a 'Loop Knot', its purpose, and its distinction from a Hitch.  History is a Bitch - live with it...

#1010 is a Loop Knot, formed from a fully loaded (i.e. one leg to the SP) turNip which in turn grips, and is stabilised by, a Bight Component, the BC in turn is stabilised by its collar bearing around the loaded SP.  The loop is made between the remaining turNip leg and one of the Bight Component legs.

Derek

[DerekSmith]

btw Derek, I believe ?clearing out the clutter of history? to be a fool?s errand.  By and large, the knots we have today, and the names of those knots are a messy product of messy history.  Live with it accept it, it?s not gonna change by decree of the IGKT (or any other way)

cheers
andy

Andy, I agree, 'Clearing out the clutter... is a fools errand'.  I misspoke when I made that statement.  What I should have said was - 'leave history where it is and start from a fresh perspective, unencumbered by history'.  The trouble is, I am finding it a bit hard to envision a compromise between 'ignoring history' and 'selectively ignoring history'.

Dan holds that a 'knot' is the marriage of a loading pattern with a 'tangle', and I agree with him (although I prefer the term 'core' to 'tangle', as core seems to infer a greater level of 'intention).

#1010 has a core comprising just two components.  The characteristics of those two components and the way they are enmeshed to give support, containment and stability to each other, form the basis of a core that has such great utility it has been used and reworked many times over in the world of cord users.

The core formed by the turNip and the BC can be called anything we like - 1st core, White Core, the TB Core, etc.  In the past, I have allowed history to influence me, and I have called it the SbC (Sheetbend Core).  That was probably my first mistake, because it immediately had knotters up in arms the moment I suggested that #1010 was the SbC married to a loop loading configuration.

The SbC (I will continue calling it this until we can agree on a more fitting acronym), despite its simplicity, is amazingly versatile and usable in the vast majority of the possible loading patterns.

The concept that #1010 is the SbC loaded with the Bowline configuration, or that #1431 is the SbC loaded with the Sheetbend configuration, hits a solid wall of rejection the moment it faces the 'historical' perspective.  This stems, I believe, from Ashley's insistence that a knot's use and mode of tying are what defines its classification - see #71 to #73.

So a new question raises its head - does the core define the Bowline or does the Bowline loading pattern define the Bowline?  If it is the latter or both, then we need to define the 'Bowline Loading Pattern' - any takers?

Derek

[Dan_Lehman]

Dan holds that a 'knot' is the marriage of a loading pattern with a 'tangle',
and I agree with him (although I prefer the term 'core' to 'tangle',
as core seems to infer a greater level of 'intention).

But Dan found that his conception had inherent aspects
of orientation/position/even-setting that he'd overlooked,
and it lost its shine to him.  --or it sets some strictures on
what a "tangle" is?

My paradigm was this "sheet bend" structure as discussed,
since the general geometry that can arise from looking only
at the --exploded-- "nub" part (excluding possible "eye" e.g.)
seemed so amenable to being the base for prescribing particular
loadings (of 1-vs-2 "ends" to make the eye knot, bowline
or all-vs-all for the net knot or ...).  But then I realized that
the Lapp bend end-2-end knot really had what corresponded
to the bowine's S.Part pulled down into a quite different angle,
away from the viewer by the usual perspecitve (since the once
"collar", "bight component" now surrounded an free end)!
Moreover, I realize that the marlinespike hitch structure --here,
hitching to the tail-- can suggest further complications of geometry
in a "tangle", and of loading trickiness :: i.e., that it's not so simple
as just prescribing "1 vs 2+A", but might require some ordered
sequence of loading to achieve the desired result.  (In the case
of the above hitch-&-object basis for (capsizing into) a bowline,
it can be dismissed as not really "en-tangled" in the one part
running straight through others (though Derek shows this as
a "component"!?); but make a U-turn with this end and bring
it back into the entanglement and one has the basis, with
careful loading, to obtain a "end-bound bowline" !
Similarly, the carrick bend tangle could take the historically
common form of that lattice, or one of joined crossing knots?!

I've not looked far in testing the "tangle" notion, but it
does seem that I've made unrealized assumptions about
it that need more consideration, but that show problems
with easy application of it.   <darn>

--dl*
====

[knot rigger]

?!  You mean that you've been unable to preserve the knot's
loop --central nipping loop-- by relaxed dressing?!  Try better!

perhaps I gave up to soon   sorry to disappoint you.  Perhaps I failed in my translation of "Lehmanese into Laymanese" (hilarious Derek! and spot on!).  I did try, honest, but whenever I think I had it sorted (ah ha! Dan is brilliant) I would load the loop of the knot, and what I had would capsize into something that looked neither bowline, or simple.

I grant you that there is a spectrum of ease of setting a knot, from the ease of just pulling on two ends of a basic overhand knot.... to carefully balancing and teasing required form a star knot.  I propose that for the sake of simplicity, a bowline need be nearer the overhand end of the scale rather than the star knot.

your point:

one can see photos in yachting magazines
where the collar seems (IMO) too loose and yet those knots
remain identifiably bowlines.

Is a very interesting one, addressing the necessity and function of a collar.  I too have observed bowlines with loose collars.  With a loose collar, the structure of a bowline becomes essentially that of ABoK #172, a Bellringer's knot.  Not a secure loop knot, but in can securely be used it as part of a quick release trucker's hitch (name used by grog) a variation of ABoK #2126.  I have used a more secure variation of this trucker's hitch (used to hold up the sidewalls of a big top circus tent).  The nipping turn is doubled in the fashion of an awning hitch (#1854) or a rigger's hitch (#1735) which increases security, but when the load is slacked, the knot is easy shaken loose (this feature being of great use when it came time to dismantle and move the big top)  So back to bowlines: would a double bowline with the second nipping turn "tucked up" like #1854 have any merit?  Anyone know a name?  Awning bowline?

moving on:

A bowline is a simple knot composed of
 one collar and
 not more than two nipping turns,
 which forms an eye composed of one or two fixed loops.

So, no triple-eye "bowlines"?

Dan, I'm all for "clip three" bowlines.  Not including them in my stab at definition was accidental, but it does illustrate the problem of "where to draw the line"  If three loops is good, why not 4?  Is a bowline on a coil a "bowline" or "bowline like"?  Now I wonder what merit a "clip three bowline" has over the old standby of #1080, a bowline on a bight?  Perhaps 4 parts of line squeezed by the nipping loops is stronger? 

"simple" seems a gratuitous --and dubious in being judgement--
part of your definition (remove it : what changes? ; replace it
with "complex" : what could that mean?).  I.e., by the rest
of your definition --which is more objective--, you pretty well
prescribe simplicity.

an excellent point Dan.  Indeed, my slipping in "simple" into my attempted definition was admittedly beating the "simple" point I was trying to make into the ground!

Derek

Finally, in the spirit of 'Living with it', I am still sticking with Ashley's lovely depiction of a Bowline in #39 where he defines clearly a 'Loop Knot', its purpose, and its distinction from a Hitch.  History is a Bitch - live with it...

a succinct and eloquent rejection of the proposed use of "eye" knot rather the "loop" knot.  I am prone to agree with you.  I see the main argument for "eye" and against "loop" is that "loop" has been made somewhat ambiguous through mis-use, or perhaps over use.  I believe I can embrace both "loop" and "eye".  While they don't mean exactly the same thing, within the context of defining a bowline (or other loop knots) they are nearly synonymous IMO.

Andy, I agree, 'Clearing out the clutter... is a fools errand'.  I misspoke when I made that statement.  What I should have said was - 'leave history where it is and start from a fresh perspective, unencumbered by history'.  The trouble is, I am finding it a bit hard to envision a compromise between 'ignoring history' and 'selectively ignoring history'.

Can any of us truly be "unencumbered by history"?  My wife tells me I have a talent for "selectively ignoring history"! Perhaps I can help?  

In the context of knotting, and your "fresh perspective" I counsel all of us to base our decisions on utility and merit.  Some nomenclature and ideas in knotting literature and history may be discarded or at least updated, but others are basic foundation material.  (making the distinction is clearly the difficult part!)

#1010 is a Loop Knot, formed from a fully loaded (i.e. one leg to the SP) turNip which in turn grips, and is stabilised by, a Bight Component, the BC in turn is stabilised by its collar bearing around the loaded SP.  The loop is made between the remaining turNip leg and one of the Bight Component legs.

Your definition is an improvement on mine.  I prefer "nipping loop" to "turNip".  As far as "Bight Component" goes, I was using "collar" to mean the same thing, but I can see that they are slightly different.  I dislike the word "component" as I think it's redundant when used in context (we're talking about the 'components' of knots)  It is troubling to drop "component" from the term, leaving only "bight"... which can be ambiguous.  Specifically, what you're (we're) trying to describe I think is a type of bight, which is squeezed by the nipping loop and also passes around the standing part.  I was working with the notion that "collar" described and defined that idea... but perhaps it doesn't.  Would a bellringer's knot have your "bight component"?  Now that I think about it, perhaps "collar" (as i've heard it used, and use it) doesn't describe "a bight which is squeezed by the nipping loop and also passes around the standing part" perfectly, or specifically enough.  I use "collar" to describe the similar part of a butterfly knot, or a zepplin bend, but those structures don't fit the specific definition as used in "bowline". 

Perhaps "collar" is simply a bight which passes around the standing part, and we add another ingredient to our definition.

#1010 has a (1) collar and (2) nipping loop which (3) squeezes (nips?) the collar legs.

(if there were a crossed eyes emoticon, i would use it here now)

So a new question raises its head - does the core define the Bowline or does the Bowline loading pattern define the Bowline?  If it is the latter or both, then we need to define the 'Bowline Loading Pattern' - any takers?

I think it must be both, and as far as 'bowline loading pattern' goes : I know it when is see it!  LOL  It seems obvious, which means it probably isn't!  It's a fixed loop.  The SbC (for lack of a better moniker) plus a standing loop = bowline.

I've attached a pic of the "awning bowline" I'm sure a better name already exists, and hopefully someone can enlighten me.

finally, thanks Derek for prompting me to go back and take a fresh look at chapter one of ABoK

cheers
andy

[agent_smith]

This should ignite the BBQ.

[ ] #1152 (Sheepshank)
[ ] #1431 (Sheet bend)

Do these structures have 'nipping loops'?

I maintain my [tenuous] position that a nipping loop must be loaded at both ends - to meet the definition of a nipping loop.

In my view, both nipping loops in the Sheepshank are loaded at each end. This does not make a Sheepshank a Bowline... but, it does mean that the Sheepshank borrows a key 'component' from the Bowline. A Bowline has a fixed eye whilst a Sheepshank has none and also...there is no collar-capstan. So a Sheepshank could never be classified as being a 'Bowline' - because at least 2 fundamental components are missing.

A Sheetbend has a collar-capstan but it does not have a fully functioning 'nipping loop' on account of only one end being loaded. Also, there is no fixed eye. Therefore, a Sheetbend could never be classified as a Bowline because it is missing at least 2 fundamental components. Also, a Sheetbend is configured from 2 separate pieces of rope which are united. A Bowline is configured from a single piece of rope.

Mark

[DerekSmith]

 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.

snip....

I can feel another debate coming...

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.

Mark,

I though that you had accepted that the turNip in the Bowline does not have to be loaded both ends?

Do you now have new evidence that the definition of a nipping loop (turNip) must be loaded at both ends?

If not, then can we move on with the corrected definition?

As for the #1152 and #1431.  Of course, neither of these are not bowlines because neither are loop knots.

Derek

[agent_smith]

I though that you had accepted that the turNip in the Bowline does not have to be loaded both ends?

No - I think you misinterpreted me!

Also, a great once man told me (a long time ago - in a galaxy - far far away):  "If everyone's thinking the same, then somebody isn't thinking!"

Do you now have new evidence that the definition of a nipping loop (turNip) must be loaded at both ends?

My evidence is in 3 parts:
1. Its my cognitive thought processes - forming a view - with considered evaluation of the core gripping mechanism of a Sheet bend core in comparison to a Sheepshank. These structures I then compared these structure with a Bowline and how that core functions.

2. It narrows (rather than w-i-d-e-n-s) the definition of a 'nipping loop' [yes, this argument is tenuous but still has some merit]

3. In my personal view, a nipping loop is a compression element - and therefore, for it to properly function - it should be loaded at both ends. And this is where I draw the line with the core function of a Sheetbend. There is no fully functional compression element because it is only loaded at one end. However, the Sheetbend does have a 'collar-capstan'.

I need to further study the core functional elements of both the Sheetbend and the Sheepshank so I can fully consider all the facts...

[Dan_Lehman]

I though that you had accepted that the turNip in the Bowline does not have to be loaded both ends?

Is a fig.8 (base, 1st-made structure) a knot with
a turNip --looks much like that of the sheet bend
and then the loop's tail just continues around to make
the rest of the '8',
  . . . exiting out into space . . .
and can return (to complete the eye for an eye knot) into
this 8 in a bight-finish 'a la bowline.
But back to the question, do we have a turNip here?
(And if so, I'd think ... a *bowline* follows!)


Meanwhile, Agent_Smith sees no eye in the sheepshank
while I see TWO --aye-aye!
.:.  Ergo, "double bowline" !
QED

--dl*
====

[DerekSmith]

I though that you had accepted that the turNip in the Bowline does not have to be loaded both ends?

No - I think you misinterpreted me!

Also, a great once man told me (a long time ago - in a galaxy - far far away):  "If everyone's thinking the same, then somebody isn't thinking!"

General Patton's quote  has been discussed, and the argument made that Patton was suggesting that multiple perspectives were important in arriving at a strong conclusion, and this Forum is very much here to air as many perspectives on a topic as possible.  So from that reasoning, I have to agree, seeking different perspectives is important.

However, as some of the Generals other quotes demonstrate, his opinions are sometimes dubious....

"If everybody is thinking alike, then somebody isn't thinking."

"If I do my full duty, the rest will take care of itself."

"In case of doubt, attack."

"It?s the unconquerable soul of man, not the nature of the weapon he uses, that insures victory."

The last one, I rather think that it is the unthinking, uncaring, soullessness of man armed with unbeatable weapons that has led to so much slaughter of humanity...

Derek

[DerekSmith]

My evidence is in 3 parts:
1. Its my cognitive thought processes - forming a view - with considered evaluation of the core gripping mechanism of a Sheet bend core in comparison to a Sheepshank. These structures I then compared these structure with a Bowline and how that core functions.

2. It narrows (rather than w-i-d-e-n-s) the definition of a 'nipping loop' [yes, this argument is tenuous but still has some merit]

Mark,  are you confident that 1. and 2. constitute evidence that a nipping loop must be loaded at both ends?

Are you saying that your definition requires the term 'Nipping Loop' to include the requirement for both ends to be loaded, or are you holding that a nipping loop cannot 'nip' if it is only loaded one end (the second end clamped)?

Either way, you are going to need to address the situation of a Bowline with one leg trapped and loaded 100% which can lead to a turNip performing (nipping) correctly while directly loaded only on the SP end.  This is still a Bowline performing under one of the extremes it is expected to handle.

Alternatively, you are going to have to restrict the range of operations the knot can be subjected to in order for it to qualify as a Bowline.  i.e. disqualify the Bowline when it is only loaded on one leg.  Personally, I think this would be a silly distinction resorted to only to justify a distorted definition.

3. In my personal view, a nipping loop is a compression element - and therefore, for it to properly function - it should be loaded at both ends. And this is where I draw the line with the core function of a Sheetbend. There is no fully functional compression element because it is only loaded at one end. However, the Sheetbend does have a 'collar-capstan'.

Yes, a nipping loop must be opposing loaded both ends, otherwise an unopposed end would simply respond to load on the other end by following it out of the knot.

The key to this issue though seems to be that you do not want to accept that a clamped end is capable of allowing the turNip to 'Nip' i.e. supply compressive force, and you resort to the opinion that it must be clamped both ends "for it to properly function".  So, yet again, when it is not functioning 'properly' as in an end clamped turNip, is this no longer a Bowline?

What I am starting to take from your responses, is a perception that a Bowline made and used 'optimally' has a turNip loaded both ends, but when the Bowline is subjected to non ideal usage, it is still a Bowline because a) that is what it was made as and b) that is what it will revert to when usage returns to 'normal'.

I can accept a degree of mileage from this perspective, in that if sufficiently abused, the Bowline will morph into a noose.  This noose is certainly not a Bowline, and in the transition from clear Bowline to clear noose, there are a continuum of stages when the knot is neither one form, nor the other.

So, my position comes down to either you are forced to define a Bowline under 'idealised' conditions, or you are forced to accept that a Bowline functions perfectly well with one end clamped and so drop the then meaningless constraint of 'both ends actively loaded'.

Finally :-

There is no fully functional compression element because it is only loaded at one end.

Seriously ??

How 'fully functional' does it have to be?  The Sheetbend has to be one of the most used knots of all time.  It utilises one loaded and one clamped end and is(was) used in the most arduos of environments.  I don't think it would have been used for long if it did not come up to being 'fully functional' do you?

Derek

[Dan_Lehman]

My evidence is in 3 parts:
1. Its my cognitive thought processes - forming a view - with considered evaluation of the core gripping mechanism of a Sheet bend core in comparison to a Sheepshank. These structures I then compared these structure with a Bowline and how that core functions.

2. It narrows (rather than w-i-d-e-n-s) the definition of a 'nipping loop' [yes, this argument is tenuous but still has some merit]

Mark,  are you confident that 1. and 2. constitute evidence that a nipping loop must be loaded at both ends?

Are you saying that your definition requires the term 'Nipping Loop' to include the requirement for both ends to be loaded, or are you holding that a nipping loop cannot 'nip' if it is only loaded one end (the second end clamped)?

In l00king at a somewhat-corresponding sheet bend
--or, using the similar, wrongly derided "left-handed bowline"--,
the opposite-sided version will produce a more *rounded* turNip
(of the end-2-end knot),
which while not changing the base of this argument,
does give an image that swings in Derek's favor.

Either way, you are going to need to address the situation of a Bowline with one leg trapped and loaded 100% which can lead to a turNip performing (nipping) correctly while directly loaded only on the SP end.  This is still a Bowline performing under one of the extremes it is expected to handle.

Here I quite beg to differ :: How can differently loading
a knot --indeed, going from eye loading to end-2-end
loading (and then there's turNip-only loading, "through
loading")-- at all be reasonably considered, for knot
theory, dealing with the same knot?!  In practical
circumstances, one will want to consider possible effects
of usage --perhaps the risk of lowering with a large eye
and snagging the up upon something such that the
lowering S.Part lowers to become untensioned while
the eye knot becomes "ring-loaded" and the knot, in
knot theory terms transforms into an end-2-end knot!

But in shaping definitions, I don't accept that knot classes
are immune to such changed loading profiles; indeed, I
posit that *knot* entails a particular profile.

Alternatively, you are going to have to restrict the range of operations the knot can be subjected to in order for it to qualify as a Bowline.  i.e. disqualify the Bowline when it is only loaded on one leg.  Personally, I think this would be a silly distinction resorted to only to justify a distorted definition.

Yes, that is what I will do, for knot theory.  When I haul
your bowline up through some "V" such that the nub abutts
and jams, I'll be loading that knot qua stopper.  (Should I for
some reason be hauling on the tail, I'd have Ashley's stopper
with one section way loose (the former eye part)!)

So we have, as I've previously remarked, two ways of seeing
"knot", both with good reason to be used, but separable to
different regions of discussion/usage.

3. In my personal view, a nipping loop is a compression element - and therefore, for it to properly function - it should be loaded at both ends. And this is where I draw the line with the core function of a Sheetbend. There is no fully functional compression element because it is only loaded at one end. However, the Sheetbend does have a 'collar-capstan'.

Yes, a nipping loop must be opposing loaded both ends, otherwise an unopposed end would simply respond to load on the other end by following it out of the knot.

BEWARE MIXING THEORY & REALITY/materials :
what you describe is precisely what happens when you
load an agreed-by-all-as-it-is-our-paradigm/basis BOWLINE
in HMPE cord --the "ongoing eye leg" feeds through the
turNip and out ... , collapsing the eye to the object
of resistance, and then going from their, ignominiously!!
SO, did our paradigm knot bowline just cease to be that,
during/for THIS loading & material?!
THIS is why I move away from behavior to "appearances",
as in, e.g., calling the venerable two half-hitches & midshipman's
hitch "nooses" (maybe selecting "noose hitch" for the former)
and not "hitch" & "eye knot" ; I don't want my knot to change
classifications per force or material!

And so while I understand and sympathize with Derek's
point about knot physics per "clamped" ~= "loaded both ends",
I move towards what perhaps underlies Mark's point of view;
in my direct terms, I'll say "in favor of *appearances*" --though
that then leads to perhaps equally problematic deliberations!?

(Recall that I --I think(!)-- advanced my "mirrored bowline"
--i.e., that water-bowline-like-but-with-larkshead-base knot
with "Janus" collaring of the "ongoing eye leg"--
as a case that appeared to have just the sort of nipping turn
(in fact, TWO) Mark insists upon and yet practically more of
the clamped-but-not(much)-loaded such leg, overall --at least
the 2nd/following turNip must take away much force...).
I think that this should be in the *bowline* class, though
it might be pretty shy of Mark's specified loading; it does
though maintain the rounded turNip appearance.)

I can accept a degree of mileage from this perspective, in that if sufficiently abused, the Bowline will morph into a noose.  This noose is certainly not a Bowline, and in the transition from clear Bowline to clear noose, there are a continuum of stages when the knot is neither one form, nor the other.

Yes, and the ore so with many of the, what-I-call,
"anti-bowlines" --where the returning eye leg enters
the turNip from the opposite side of our paradigm:
there is greater tendency towards the turn becoming
more helical, open/extended than round & compressing.
But even the paradigm knot does this, and can go all
the way to that ("pile hitch..."-)noose structure or be
arrested mid-way, with a decided helix vice turNip.
THIS is not theory, it's observed results.


--dl*
====

ps : Recall my above question re the fig.8 base with
a bowlinesque returning-eye-leg collaring (which preserves
much of appearance...) : was that a turNip in the base
--which resembles the form in the same-side sheet bend
(and which indeed is one of the suggested securing for
that knot --an extension in which the line forms a fig.8
(the U-part/bight left unaltered, though in practice this too
might be given a securing extension, in like-diameter ropes)) ?!

[knot rigger]

Whether or not a nipping turn is loaded on one or both ends has no bearing on the definition of bowline IMO

If we define nipping turn as needing to be loaded on both ends, and then define a bowline as having a collar and a nipping turn, then a sheetbend as used as a netting knot, with all four tails loaded, would qualify as a bowline.  Clearly this definition is inadequate and must be modified.

Both Derek and Mark make convincing arguments for nipping loop to be defined as either one leg, or two leg loaded IMO.  I had previously asserted that "nipping loop" need only be loaded only on one leg (but of course loaded on two also counts).  I did so based on the logic that the difference between a sheetbend and bowline is that a bowline has a loop, and that if a sheet bend doesn't have a nipping turn, what does it have?

I think that these three ingredients must be in the definition of bowline
1) has a collar
2) has a nipping turn
3) is a loop knot (for clarity, the #1010 loop form)

if (3) is excluded and a nipping turn is defined as both legs loaded, then a sheet bend as netting knot may be included.  if (3) is excluded and a nipping loop is defined as either one or both legs loaded, then a sheetbend as a bend is included as well.

* Therefore either way a nipping turn is defined (3) must be included in the definition, and if (3) is part of the definition of "bowline" then either definition of nipping turn will describe a (#1010) bowline

In this respect, the distinction of whether or not a nipping turn has both legs loaded has no bearing on the definition of bowline. QED

However.  The sheep shank vs bowline vs sheetbend example Mark had given has merit about what is a nipping loop.  As does Derek's argument that the structure in a sheet bend provides compression (or "nip")  I propose that the non collar structure of a bowline and sheetbend, while similar, and serving similar functions, are subtlety different, and therefore subtlety different names should be applied.

perhaps:

A "nipping turn" is loaded on both ends

and

A "nipping hitch" is loaded on only one end

a sheetbend as a bend has a nipping hitch and a collar

a sheetbend as a netting knot has a nipping loop and a collar

a bowline has a nipping loop, collar, and a loop


for further clarification (ie specificity) the loop of the bowline must connect the a nipping loop leg and a collar leg, and the bight of the collar must pass around the standing part of the knot (to exclude such knots as the Eskimo bowline or Bellringer's knot)

cheers
andy

*added for clarity 1/16/15

[knot rigger]

I don't want my knot to change
classifications per force or material!

I emphatically agree with Dan's point here.