Page 261 - Geoffrey Budworth "The Pocket Guide to Outdoor Knots"

Purpose
Bottles of liquid—whether containing plant fertilizer, battery topping-up fluid or

one’s most-loved beverage—can be heavy and sometimes slippery. This is one

of a number of sling knots that exists to grip the necks of glass and earthenware
in such a way that bottles and other containers may be carried comfortably or
hung up out of harm’s way.

Tying

Begin as if to tie a Prusik knot (previous page), then impart a half-twist in the
upper bight and tuck the other bight through it (figure 1). Pull the second bight

down (figure 2) and painstakingly tighten the entire arrangement (figure 3).

Knot lore
This is—as its name implies—yet another ingenious contrivance from the

inventive fingers of Harry Asher, that first appeared in A New System of Knotting
— Volume 2 (1989).