Chambon Chambon A chambon is a piece of horse tack. It is a strap that runs forward from the bottom of the girth or surcingle, and forks. The forks continue to a ring on either side of the bridle or halter, at the base of the crownpiece. Running through those rings, the forks follow the cheekpieces to the bit. They may attach to the bit or pass through the bit rings and attach to themselves below the horse's neck. A chambon prevents the horse from raising its head beyond a fixed point. Raising the head causes the length of the chambon
Girth (geometry) width, with the same width "w". All curves of constant width have the same perimeter, the same value "w" as the circumference of a circle with that width (this is Barbier's theorem). Therefore, every surface of constant width is also a surface of constant girth: its girth in all directions is the same number "w". Hermann Minkowski proved, conversely, that every convex surface of constant girth is also a surface of constant width. For a prism or cylinder, its projection in the direction parallel to its axis is the same as its cross section, so in these cases the girth