# Knot science

Various knots and splices, Seville Naval Museum , Spain

The knots is the study of the production, differentiation, and application of nodes .

In contrast, knot theory is a branch of mathematics and deals exclusively with the properties of mathematical knots.

## methodology

Knots are mostly taught and learned through demonstration and imitation ( four-step method ). The material used is geared towards future applications: mountain ropes for climbers, ropes and hawsers for seafarers, rescue equipment for rescue services, twisted ropes for splicing , fishing line for anglers, calf rope for farmers, lines and cords for macrame . First the concrete application of a node is shown. Then the knotting technique is demonstrated and explained. Possible mistakes are discussed while practicing. Ideally, practice is carried out in a practical situation and application. For demonstration, learning and practicing, two different colored ropes at least 1 m long should be used, for example 10 mm thick rope or thick accessory cords of different thicknesses.

Alternatively, good textbooks with memorable illustrations are available. Animated nodes and films can be found on the Internet that show the sequence of actions. For many nodes there are also a number of memos that can be used as learning aids.

## exam

Mastery of knots is required for sailing and motorboat driving licenses, for fire brigade proficiency tests and for climbing training. It makes sense to check the knot in the application, for example the weaving line with a thick rope under tension to cover the bollard , or the HMS knot when climbing on the rock.

Exam knot sailing Climb fire Department THW
CH DE AT CH DE AT CH DE AT DE
Bowline x x x x x x
Schotstek x x x x x x x
Webeleinenstek (mast throw) x x x x x x x x
Eight knot x x x x x x
Round trip with two half beats x x x
Square knot x x x x (x) x x
Stopperstek x x x
Occupy on the cleat x x x
Double sheet stake x x x x x
Double bowline x x x x x
Figure eight knot x x x x x x x x x x
HMS node x x x x x x
Prusik x x x
Sack stitch x x x x
Carpenter blow x x x x

## Terms and language

The seaman's language has a differentiated vocabulary of knot science:

on slip
The knot is closed with a bay in such a way that it loosens at the end when pulled
eye
ring-shaped basic shape
bay
U-shaped basic shape
Half blow
Wrapping the fixed part with the loose part
part
Part of the leash. In the Maritime is, the fluid under train part of the load to the node fixed or stationary part. The free part behind the node is loose part. Otherwise, one also speaks during knot-tying by the fixed and the free end .
Round trip
a trip simply laid around an object with an additional eye
loop
eye attached by a knot
loop
eye formed by a knot and closed
Rope
the loose end of the line or an approx. 80 cm long line
cordage
Depending on the diameter, seafarers differentiate from thread to hawser
Trip
also eye

## Node names

Ashley's Book of Knots

There is no general or even generally valid reference to node names.

The closest thing to a nomenclature is the Ashley Book of Knots . Although Clifford Ashley has compiled the largest collection in his book and numbered each drawing, the book is not a useful reference for node names. Many nodes are listed twice. The same and similar drawings are available several times, but are listed under different numbers and often under different names. Many names are also present more than once, but show a different node or the same nodes have different names, depending on the application. In the German edition, there is also the fact that translations of the node names are also quite arbitrary and not uniform.

It can be seen that in every nation, in every language area and in every node application area, the same nodes for the same application area are named differently. In addition, there are linguistic blurring that arose from a node name in ignorance of the language. To avoid this confusion, many organizations define their nodes internally - but each organization uses different terms for the same node. When describing a knot, you can usually not avoid showing the knot, demonstrating it or depicting it, so as not to talk about different things.

The bowline should be given here as an example of the naming problem :

• Bowline: term used in seafaring
• Stake engraving: Name used by fire departments
• Rescue sling: term used by boy scouts
• Bull-Line-Knot: English name for Bullenstander-Knot
• Bowline: looping of bull line
• Bolein: Germanized looping of Bow-Line
• Bulin: Germanized rounding of Bull-Line, common in climbing
• Chest band
• Simple anchor stitch (THW)

This easily leads to confusion and misunderstanding among various users.

## Rope and material science

Knotting also includes information about the various rope materials: synthetic fibers such as polyamides , polyester , polypropylene , natural fibers such as hemp , sisal , metal such as steel , stainless steel and their properties. Another sub-area is knowledge of the different types of braiding for ropes. For example, ropes can be braided, twisted or twisted. The manufacture of ropes and the special use of the different types are a separate craft, as is knowledge of the storage, care and aging of ropes.

## Security customer

There are particularly suitable knots for every application. Nodes for similar areas of application often differ in terms of security-relevant properties. This includes in particular their so-called knot strength, which describes how much they reduce the tensile strength of the rope used.

Ropes and knots are often used to handle high forces. This is associated with dangers to health and life. In knotting, information is therefore also provided about the labeling and life cycle of the material, material fatigue due to UV radiation and chemicals, mechanical damage, secure anchoring, self-locking, external locking, etc.

The user must also know that knots can behave differently depending on the material into which they are knotted. A knot, tied in natural fiber rope, can be safe. This does not mean that such a knot is automatically secure in synthetic fiber rope; in smooth material, some knots can more easily loosen or “run”.

## literature

• Clifford W. Ashley : The Ashley Book of Knots . Over 3800 knots. How they look like. What they are used for. How they are made. Translated by Gerhard Meyer-Uhl. Edition Maritim, Hamburg 2005, ISBN 3-89225-527-X (original title: The Ashley Book of Knots ).
• Geoffrey Budworth, Rodney Forte (Photos): Knot. The practical manual. Translated by Helmut Pätz. Delius Klasing , Bielefeld 2009, ISBN 978-3-7688-2538-2 (Original title: Handbook of Knots and Knot Tying ).
• Lee Neuwirth: Theory of Knots. In: Spectrum of Science . No. D6179EX, Heidelberg August 1979, , p. 74. (Among other things: model of a mathematical node, relationships between geometry and algebra).