Although in the first instance the horse served mainly, if not altogether, as an ally of man in his contests with his neighbors, its most substantial use has been in the peaceful arts. As pack animal and drawer of the plough, the ox appears in general to have come into use before its swifter companion. The displacement of horned cattle has been due to the fact that their structure and habits make them much less fit for arduous and long-continued labor than the horse has been found to be. The cloven foot, because of its division, is weak. It cannot sustain a heavy burden. Even with the unincumbered weight of the body of the animal, the feet are apt to become sore in marches which the heavily mounted horse endures unharmed. Centuries of experience have shown that while the ox is an excellent animal for drawing a plough in a stubborn soil, and is well adapted to pulling carriages where the burden is heavy and the speed is not a matter of importance and the distance not great, the creature is too slow for the greater part of the work which the farmer needs to do. The pace which they can be made to take in walking is not more than half as great as that of a quick-footed horse moving in the same gait; and the ox is practically incapable, because of its weak feet, of keeping up a trot on any ordinary road. But for the fact that an aged ox may be used for beef, they would doubtless long since have ceased to serve us as draught animals. As it is, with the growing money value of the laborer's time, this slow-moving creature is steadily and rather rapidly disappearing from our farms. This change, indeed, is one of the most indicative of all those now occurring in our agriculture. It is an excellent example of the operations which the increase in the workman's pay is bringing into our civilization. The natural advantages of the horse for the use of man consisted in its size, strength, and endurance to burden; form of the body, which enabled a skilful rider to maintain his position astride the trunk; and the peculiar shape of the mouth and disposition of the teeth which made it possible to use the bit. With these direct physical advantages there were others of a physiological and psychic sort, of equal value. The creature breeds as well under domestication as in the wilderness; the young are fit for some service in the third year of their life, and are, at least in the less elaborated breeds, in a mature condition when they are five years old. Experience shows that the animal can subsist on a great variety of diet, being in this regard surpassed only by its humbler kinsman the donkey, and by the goats. There are few fields so lean that they will not maintain serviceable horses. They do well alike in mountain pastures and amid the herbage of the moistest plainland.