individuals. The two factors that are of the most importance are the
quality of the teeth and the character of feed. Soft teeth wear more
quickly than hard teeth, and the teeth of horses that feed over closely
cropped and sandy pastures wear rapidly because of the dirt and grit
present on the short grass. This variation in the wear is of little
importance to the person who must judge the age of a horse that he expects
to purchase by the condition of the teeth. In reality, a horse is just as
old as the wear on the teeth and his general appearance indicate. In order
to stand severe work the animal must be able to masticate the feed, and
prepare it for digestion in the stomach and intestines. The degree of wear
on the molar teeth may be indicated by the wear on the incisors. The
general condition of the horse and his ability to stand hard work depend
very largely on the condition of the table surfaces of the molars.

It is very difficult to judge the age of horses that have deformed mouths
or that are in the habit of crib-biting, because of the irregularity in the
wear of the incisors.

When examining the teeth for the purpose of determining the horse's age,
the shape of the incisors, the angle with which they meet and the
appearance of their table surfaces should be observed. The teeth of young
horses show more or less yellowish cement. At about seven years of age the
anterior faces of the teeth are usually white, later a yellowish color. The
teeth of middle-aged horses may be long, and in aged animals, narrow and
short. The incisors meet at a more acute angle in old than young horses.

_The free portion of the incisor_ tooth is flattened from before to behind.
At the level of the gums its two diameters are about the same, but the
portion of the tooth imbedded in the jaw bone is flattened from side to
side. As the tooth becomes worn off, the length of the free portion is