~Necessary Dilution.~--Even breast milk must be diluted with an equal amount of water or a 3% sugar solution. The amount of milk should be increased and the amount of dilution decreased until the undiluted breast milk is given in four or five days. Like older babies, the next best food for premature babies is the properly modified cow's milk, but the utmost care will have to be observed, as these babies are more easily upset than older and stronger ones. ~Premature Infant Feeding.~--The following method of feeding may be suggested, keeping in mind that it is an easy matter to increase the strength of a mixture if the baby shows the need of such an increase. The premature baby is rarely strong enough to take the breast. ~Method of Administering Milk.~--The most satisfactory method of administering the food in such cases is by means of the Brick feeder, which consists of a graduated glass tube, open at either end. On the small end is placed a small nipple like those seen on medicine droppers; this one is perforated and goes into the mouth of the baby. A large rubber finger cot is attached to the other end of the tube. The milk is forced into the mouth by pressing the finger cot. In case the infant is too feeble even for this method of feeding, the desired amount is dropped into the mouth from a medicine dropper; 5 c.c. (about 1 dram or 1 teaspoonful) of diluted milk being given at each feeding. This amount is increased gradually from day to day. ~Whey Mixtures.~--Whey mixtures have been found to meet the needs of premature infants more efficiently than ordinary mixtures. As the proteins in whey are in a more digestible form, they throw less work on the immature digestive apparatus. As a rule the casein and whey are in proportion of 1:1. The following formulas[81] show the amounts in which the food constituents are combined and are suitable for premature babies: Fat 1.00% Milk sugar 4.00% Total proteins 0.25% Lime water 25% of cream and milk mixture or Fat 1.00% Milk sugar 4.50% Total proteins 0.50% Lime water 25% of cream and milk mixture PROPRIETARY FOODS A word as to the use of Proprietary Infant Foods: These prepared foods may be classified under four heads, as follows: (1) condensed milks; (2) malted foods, those consisting chiefly of carbohydrates in the form of maltose and dextrins; (3) those consisting almost entirely of starch, and (4) those composed partly of soluble and partly of insoluble carbohydrates. (1) Condensed milk may be sweetened or unsweetened. These milks are never given undiluted, the directions calling for one part condensed milk to nine parts water, which gives a mixture containing 0.90% fat, 5.49% sugar, and 0.80% protein if "Eagle Brand" Condensed Milk is used.[82]