10 



PHYSIOLOGICAL CHEMISTRY. 



The solids of the body are therefore both organic and inor- 

 ganic, and approximately the composition of the whole may 

 be thus represented : 



Per Cent. 



Water 65 



Protein substances 15 



Fats '. 14 



Other organic extractives i 



Mineral matters 5 



It must be remembered, however, that the fat may vary 

 widely from the above number and therefore change the ratio, 

 fat: protein. Among the mineral matters calcium phosphate 

 holds the first place, as it makes up the larger part of bone 



