Page 101 - Patrick Moreau, Jean-Benoit Heron Marine Knots How to Tie 40 Essential Knots
P. 101
6 - The knot is finished.
The neck of the bottle can rest in the space formed by the hexagon, which, with traction, will act
like a vice and hold it without any worry that it will slide out.
Then you simply need to pass one of the two ends through the large bight and tie a bend knot
with the other end.