WHY cow's MILK ? 65 



dren, however, it is practically a perfect food — as 

 nearly perfect as anything of which we know. Its 

 advantages are well known: it is as a rule easily 

 digested, it does not irritate the alimentary canal, 

 and by using a milk diet the physician is better able 

 to regulate both the quantity and the quality of the 

 nourishment given to an invalid or an infant than in 

 any other way. Of all animal foods milk is the most 

 easily digestible. It has been found that, on an 

 average, an adult digests about 97 per cent of the pro- 

 tein, 95 per cent of the fat, and 98 per cent of the 

 carbohydrates in milk. According to the experi- 

 ments made by our American authorities, a child one 

 year old digests less — 90 per cent of the protein, 

 96 per cent of the fat, and 86 per cent of the car- 

 bohydrates.'" These figures, it may be added, repre- 

 sent the digestion of a healthy child with whom cow's 

 milk agrees. 



But the enormous death-rate among bottle-fed 

 babies shows that it is exceptional rather than usual 

 for cow's milk thus to agree with young infants, 

 especially during the first few weeks of life and during 

 hot weather, when there is a certain depression of the 

 digestive system and when it is difficult to keep milk 

 pure and sweet owing to the rapidity with which it 

 decomposes. One cause of. difficulty is the hardness 

 of the curd as compared with that in breast mUk, 

 the infant's natural food. Dr. Chapin's investiga- 



