The Horse Bridle
The bridle is the headgear of a horse, by means of which he is controlled. Bridle parts include a headstall to hold up the bit; a browband to keep the headstall in place; a throatlatch to hold the bridle on; reins to guide or check the horse; and a restraining bit.
Each end of the rein is attached to the bit. The most common bits are the snaffle, used with a single rein, and the pelham and the curb, used with two sets of reins. The snaffle bridle uses a plain, jointed bit that has rings for the reins on each side; the bar works on the lips of the horse and causes him to raise his head.
The pelham bridle, which is more severe, uses a bit that has a one-piece bar; sometimes the bar has a "port," or arch, in it for a mouthpiece. A curb chain, attached to two shanks of the bit by curb hooks, is held in place by a curb strap and aids the action of the bit. Snaffle reins attach to the upper rings on the shanks; curb reins, to the lower rings. Use of the curb reins causes the horse to lower his head and bend at the poll.
The Weymouth or full bridle has both a snaffle and a curb bit. The latter is similar to the pelham but has only one set of rings, these being at the lower end of the shanks.