The Game of Trussing

We found this one in the American Boy's Book of Sports and Games (Dick & Fitzgerald, 1864), and thought it sounded like the kind of weird fun kids just don't do anymore, probably for a good reason. (Although I think we may try it at a Cub Scout event.) I decided to call it by its alternate name rather than its original name ("cock fighting") for obvious reasons. The prose of the Boy's Book is worth quoting directly:

This game, which is productive fun, is a trial of skill between two players. It is also called "trussing," The players are made to sit down on the ground, and draw their legs up, clasping the hands together below the knees. A stick is then passed under the knees, and over the elbows of each player, as shown in the cut; and then the two players, being placed face to face, try to overbalance each other, by pushing with the points of their toes. Of course, the hands may not be unclasped; and when a combatant rolls over, he lies quite helpless, until set up again by the spectators, or by his backers. The cock who overturns his adversary twice out of three times is considered to have won the fight. 

The interesting part about this description, by some unknown and long forgotten writer (only the illustrators and the engraver are named), is the notion of "backers". Was there some kind of underground Trussing Syndicate?