in THE THEORY OF HUMAN NUTRITION 115 



This explanation is, however, inadequate, since, as we have seen 

 in the preceding chapter, the processes of oxidation are generally 

 more intense in small than in large individuals, whether men or 

 animals, because, the surface of their bodies being larger in 

 proportion to their weight, they lose a relatively larger quantity 

 of heat, and must, therefore, introduce a larger quantity of 

 heat with their food. Moreover, certain observations of Camerer 

 and Schmidt show that girls and women need a smaller quan- 

 tity of food than boys and men even when their weiglit is the 

 same. This fact is due to the less active muscular life led by 

 women as compared with men, the smaller development of the 

 muscles and the greater thickness of the subcutaneous adipose 

 layer, which contributes to the charm and grace of the female 

 figure, and finally the less intense metabolism of the women. 



A gradual increase in the regular diet is, however, observed in 

 women both during pregnancy and nursing, because during these 

 two functions peculiar to the sex the foetus and the new-born 

 child are nourished at the expense of the blood and milk of the 

 mother. 



The mother's milk is the best and most natural nourishment 

 for the infant when her state of health, both as regards her 

 general condition and the quantity and quality of the mammary 

 secretion, permit suckling. When this is not possible and a good 

 wet-nurse cannot be obtained, the child should be given ass's milk, 

 which closely resembles that of woman, or humanised cow's milk, i.e. 

 a mixture consisting of of a watery solution containing 14*3 per 

 cent lactose, and f of fresh cow's milk. The percentage com- 

 positions of human milk, cow's milk, and the above-mentioned 

 mixture are as follows : 



Protein. Fat. . Lactose. Salts. Water. 



Woman's milk . 2-01 3'74 6-37 0-30 87'58 



Cow's milk . . 3-35 3-55 4'88 0'70 87-52 



Humanised milk . 2'23 2-37 8O2 0-48 86'91 



From these data we see that humanised milk as compared 

 with woman's milk contains a little more protein, but 1/37 per 

 cent less fat, which is made up by 1'65 per cent more lactose. 



Konig's statistics of infant mortality according to the different 

 forms of nutrition are extremely striking. Out of 1000 children 

 after 1 year 



610 of those nursed by their mothers were nourishing, and 82 were dead. 

 260 of those who had wet-nurses 180 



90 brought up by hand 510 



The results of the numerous researches upon the increasing 

 intake of food by children during the first year of life, which were 

 carried out by Camerer (1894), Rubner and Heubner (1898), 

 Proscher (1898), and Joannessen and Wang (1898), are shown in 

 the following table drawn up by Konig : 



