(1) The snaffle should just touch the corners of the mouth.

(2) The bar of the bit should normally lay midway between the corner teeth and the corners of the mouth, and should be level on both sides.

(3) The curb chain must come quite flat into the chin groove when the bit reins are felt. Carelessness or hastiness in putting on a bridle is no doubt the reason for one finding curb chains put on incorrectly. If one was to examine all the horses out hunting in a large field one would find an extraordinarily large percentage of them badly bridled. The curb chains in most cases would be either hooked on wrong or they would require another twist before being attached to the curb hook.

Correct adjustment of the curb chain is most important, because if it is not quite smooth in the chin groove there will be more pain felt below the jaw than above it, consequently under these conditions a young horse will resent lowering his head and relaxing his jaw.* If the curb chain comes above the chin groove it will cause soreness. A sound guide for judging how tight a curb chain should be is when the reins are felt sufficiently for the curb chain to have a bearing on the chin groove, the cheek of the bit should be at an angle of 45 degrees with the bars of the mouth. If the curb chain is looser the bit will follow through and will not maintain its full lever action. If the curb chain is too tight, the bit becomes more severe and is more or less continuously bearing on the tongue and the bars. This will irritate a young horse, harden his mouth, and possibly make him keep his tongue over the bit.

* On an old horse that is inclined to hang on the hands the curb chain may be worn rough. But this is not recommended for young horses.

(4) If the bit is too narrow it will bruise the sides of the horse's mouth and upset his temper.

(5) If the bit is too wide it may work to one side of the mouth so that the edge of the port may rest on one of the bars of the mouth; this will cause an uneven pressure and a onesided mouth. The curb chain, also, instead of having an even bearing all round the chin groove, will press on one spot and cause soreness.

(6) A long cheek and high port increases the severity of the bit. Too high a port may bruise the roof of the mouth. The tongue fitting into the port produces a stronger bearing of the bit on the bars of the mouth; whereas with a straight bar bit a considerable amount of the bearing is taken on the tongue.

One-Sided Mouth

Generally a horse is more comfortable with sufficient port to give freedom to his tongue. With a one-sided mouth the bit may be dropped a hole lower on the hard side.