It is recognized as a principle in feeding animals that the quantity and quality of the food should bear a distinct relation to the purpose for which the animal is intended. With reference to the horse, it is always the case that the immediate object is to preserve the animal's health and condition, so that he may be able to do the largest amount of work without injury. With cattle, sheep, and swine, the attention of the feeder is directed towards the attainment of as much fat and flesh as it is possible to derive from the food with which the animal is supplied. With this system of fattening animals for the purpose of food the horse-owner has absolutely no concern, and the system, therefore, is considerably simplified, as the horse-owner is only required to exercise his judgment in determining what amount and what quality of food is necessary to keep the animal in the best working condition. In the chapter on stable management the details of ordinary practice are described, and it will be seen that the quantity of food which a horse can advantageously consume varies in proportion to the amount and character of the exertion which the animal has to perform; the materials employed remain the same - for example, oats, hay, wheat, straw, and bran, with occasional small quantities of carrots or turnips, and, at certain seasons, grass. In ordinary work a horse will consume daily, on the average, three quarterns of oats, with a small quantity of bran, and the addition of what is roughly calculated as a double handful of chaff composed of chopped hay and straw. A truss and a half of hay in the rack per week is a reasonable allowance. The very wide limits which are permissible, and, indeed, advantageous, in regard to quantity may be gathered by reference to the feeding of a brougham horse in the most active part of a London season, during which comparatively short time a number of horses are worked out, as it is called, in spite of the amount of food which they consume, and are disposed of at the end of the time, often in a very feeble condition. A cab horse, again, in constant work in a large town, consumes an amount of provender which varies with the animal's appetite and the opportunities which may be afforded for taking food. Usually the nose-bag is put on every time a journey is ended, and an interval is therefore allowed to the animal for refreshment. Notwithstanding the amount of provender which hard-worked horses will consume, it is evident that the exhausting; effects of excessive exertion are not prevented by excessive feeding; but it is, on the other hand, quite certain that horses which are called upon to perform excessive work do better with a practically unlimited allowance of food - by which is meant supplying as much food as the animal is disposed to take - than they do when the quantity is limited.