Pasteurisation of milk consists in heating the milk to a high tempera ture, which is maintained for a period of 15 to 3o minutes. Special forms of apparatus have been recommended for this purpose. Simple Pasteurisers may be purchased in any large drug-store, Freeman's apparatus being one of the cheapest and most serviceable. This apparatus (see Figs. 305, 306) consists of a well-covered pot, containing several compartments for the milk bottles. The process takes place as follows : As many bottles as are needed are filled with milk, and closed with tufts of cotton, whereupon the pot is three-quarters filled with water by means of a hose attached to a faucet. The pot is thereupon covered, and brought to a boil, a temperature of about 14o° F. being maintained for about half an hour. This done, the rack holding the bottles is lifted out of the pot and immersed in hot water, which may gradually be cooled until the milk has the desired temperature. The cotton-stoppers must never be removed until the milk is to be used, when the nipple, which has been carefully cleaned (preferably boiled), is immediately attached. \Vhen given to the baby the milk should be heated to 98? F., the temperature of the body. Milk treated in this manner will not keep fresh for more than about 24 hours. A special advantage of this method is that the comparatively low temperature to which the milk is heated does not change the character of its casein, winch remains more easy of digestion than as found in boiled milk. Nor does Pasteurised milk have the unpleasant taste of milk boiled in an ordinary pot.
The time of feeding should not exceed twenty minutes. If the bottle be not empty after this period, or if the infant vomit immediately after drinking, the amount of food should be diminished. On the other hand, if the baby drink eagerly and rapidly, the quantity given at each meal may he gradually increased. Milk left in a bottle should not be warmed and used again, but should be thrown out at once. While the baby is being fed it should be held upon the left forearm of the mother or nurse, with its head slightly elevated, the nurse holding the bottle in her right hand. Older babies may hold their own bottles.
The bottles, as well as the rubber-nipples, should be kept scrupulously clean, and should be boiled frequently in a solution of soda (three dessert spoonfuls to one quart of water), or in a soft-soap solution. Immediately after feeding, the bottle should be cleansed with hot water and a bottle brush, whereupon it should he filled with water and remain standing until used again. The bottle-brush should likewise be boiled frequently, prefer ably every day. An entirely smooth bottle, without dents or ornaments, should be used. Bottles that are graduated on the inside should be avoided, as any unevenness tends to collect dirt, thus permitting infection. Straight, cone-shaped bottles are most practical. The rubber-nipples should be smooth, and perforated with two holes. These holes should be so small that
the milk will be prevented from running into the baby's mouth without suction, the object being to have the infant draw the milk from the bottle as from a breast. This causes the baby to become tired, and to fall asleep immediately after feeding. Rubber and glass tubing should be avoided, as they cannot be satisfactorily cleaned.
The quantity of food to be given to a baby in the course of twenty-four hours must be governed by the age and weight of the child. It is advisable to begin with a quantity of from 3 to 12 ounces during the first few days after birth, slowly and gradually increasing the amount to one quart at the end of the fourth month, and to half a pint more at the end of the sixth month. Sensitive infants may be fed at the rate of 5 to 6 ounces to every 2 pounds of their weight. A baby weighing 7 pounds should thus be given between 17 and 22 ounces of milk in the course of twenty-four hours ; an infant of S pounds, between 20 and 24 ounces ; and one weighing 10 pounds, between 25 and 3o ounces. The best way is always to begin with small quantities, and to increase gradually. A baby in good health may be given even larger quantities than those here mentioned.
The amount of proteins being about 3 to 4 times larger in cows' milk than in human milk, it is necessary to dilute the former in order to render it digestible for baby's stomach. In diminishing the percentage of albumin, however, the amounts of fat and sugar are also diminished. The loss of sugar may be compensated for by the addition of milk-sugar or cane-sugar at the rate of one teaspoonful to every three ounces of water added. The following formulas, taken from Dr. Louis Fischer's " The Health-Care of the Baby," are of value in showing the proper dilution of cows' milk for babies of various ages : Rice-water is made by adding one table-spoonful of rice to one quart of water, and boiling it for two hours, adding more water from time to time. \Vhen done, it should be strained through muslin, and enough boiled water added to make it measure one quart. If an inclination to diarrhoea be present—that is, if the excrements are of a soft or thin consistency, readily separating in the diapers—it is well to use barley-water or oatmeal-water with the milk instead of pure water or rice-water. The methods of prepara tion are the same as that given for rice-water. If a constipated condition prevails, sugar of milk should be used instead of cane-sugar, and the per centage of fat increased by adding cream to the mixture. This addition of fat increases the digestibility of diluted cows' milk, and renders it more like human milk in composition. Infants who do riot thrive should always receive such an addition of fat in their bottles. Various cream-mixtures have been introduced, but these, as \yell as all specific directions for feeding infants, should be left to the attending physician to prescribe.