BODY TISSUES AND FLUIDS 



479 



ash of human milk for different periods and also for cow's milk, their 

 figures being given in the table below. As will be noted the high ash of 



AVERAGE PERCENTAGE COMPOSITION OF THE ASH OF HUMAN AND Cow's MILK 



the colostrum period is due chiefly to the amount of NaaO and K 2 O. Of 

 the salts which make up the ash, the greatest individual, as well as the 

 greatest period, variations are seen in the Na 2 O. The largest constituent 

 of the ash of human milk is K 2 O, this with the CaO together making up 

 more than half the total ash. Although in amount the total ash of cow's 

 milk is about three and one-half times as great as that of human milk, 

 the proportion of different salts which make up the ash is nearly the 

 same, the only exception being that cow's milk has more Pa^ 

 less iron. 



