Bowline work "A Sea Grammar" under the name Boling knot. Smith considered the knot to be strong and secure, saying, "The "Boling knot" is also so firmly made and fastened by the bridles into the cringles of the sails, they will break, or the sail split before it will slip." Another possible finding was discovered on the rigging of the Ancient Egyptian Pharaoh Khufu's solar ship during an excavation in 1954. The bowline is used to make a loop at one end of a line. It is tied with the rope's working end also known as the "tail" or "end". The
Arf invariant of a knot the knot, constructed from a set of curves on a Seifert surface of genus "g" which represent a basis for the first homology of the surface. This means that "V" is a 2"g" × 2"g" matrix with the property that "V" − "V" is a symplectic matrix. The "Arf invariant" of the knot is the residue of Specifically, if formula_3, is a symplectic basis for the intersection form on the Seifert surface, then where formula_5 denotes the positive pushoff of "a". This approach to the Arf invariant is due to Louis Kauffman. We define two knots to be pass equivalent