Water bowline the working end around the standing line and back through both half hitches. This is illustrated in the three pictures below. Water bowline The water bowline is a type of knot designed for use in wet conditions where other knots may slip or jam. Although similar in finished appearance to the double bowline, the water bowline is formed with a clove hitch as the loop in the standing part of the rope. This is similar to the double bowline, which puts the running end through a round turn. The additional friction from the clove hitch increases the security of this
Arf invariant of a knot if they are related by a finite sequence of pass-moves, which are illustrated below: (no figure right now) Every knot is pass-equivalent to either the unknot or the trefoil; these two knots are not pass-equivalent and additionally, the right- and left-handed trefoils are pass-equivalent. Now we can define the Arf invariant of a knot to be 0 if it is pass-equivalent to the unknot, or 1 if it is pass-equivalent to the trefoil. This definition is equivalent to the one above. Vaughan Jones showed that the Arf invariant can be obtained by taking the partition function of a signed planar