constitution, it may be destructive to the child; and that where this cannot be obtained, and cow's milk is found to disagree, ass's milk may sometimes be resorted to with the happiest results.[FN#8] [FN#8] An infant will generally consume a quart, or a little more, of ass's milk in the four and twenty hours; and as this quantity is nearly as much as the animal will give, it is best to purchase an ass for the express purpose. The foal must be separated from the mother, and the forage of the latter carefully attended to, or the milk will disagree with the child. Sometimes the mother's breast, and every description of milk, is rejected by the child; in which case recourse must be had to veal or weak mutton broth, or beef tea, clear and free from fat, mixed with a very small quantity of farinaceous food, carefully passed through a sieve before it is poured into the sucking-bottle. THE MODE OF ADMINISTERING IT.--There are two ways--by the spoon, and by the nursing-bottle. The first ought never to be employed at this period, inasmuch as the power of digestion in infants is very weak, and their food is designed by nature to be taken very slowly into the stomach, being procured from the breast by the act of sucking, in which act a great quantity of saliva is secreted, and being poured into the mouth, mixes with the milk, and is swallowed with it. This process of nature, then, should be emulated as far as possible; and food (for this purpose) should be imbibed by suction from a nursing-bottle: it is thus obtained slowly, and the suction employed secures the mixture of a due quantity of saliva, which has a highly important influence on digestion. Too much care cannot be taken to keep the bottle perfectly sweet. For this purpose there should always be two in the nursery, to be used alternately; and, if any food remain after a meal, it must be emptied out. The bottle must always be scalded out after use. The flat glass nursing-bottle itself is too well known to need description; it may be well, however, to say a word about the teat that covers its narrow neck, and through which the infant sucks the food. If the artificial or prepared cow's teat is made use of, it should be so attached to the bottle that its extremity does not extend beyond its apex more than half or three quarters of an inch; for if it projects more than this, the child will get the sides of the teat so firmly pressed together between its gums, that there will be no channel for the milk to flow through. This remark applies equally to the teat made of soft wash- leather, which many ladies prefer to that of the cow, and it is a good substitute; but then a fresh piece of leather must be made use of daily, otherwise the food will be tainted, and the child's bowels deranged. It is also necessary that both of these, when used, should have a small conical piece of sponge inclosed.