34 CHEMICAL PHYSIOLOGY. 



the albumen or white of egg. This is completely 

 precipitated by boiling in the presence of a little acetic 

 acid. If no acetic acid is present, sodium albumen, 

 formed during the process of coagulation, remains in 

 solution. 



The serum contains neutral fats and soaps in solution 

 or suspension, in the latter case being rendered milky 

 or turbid thereby. In cases of disease which I have 

 made known the serum also contains free fatty acids. 

 - These acids are emulged with the phosphate of 

 sodium of the serum, and after extraction by ether are 

 again easily emulged by boiling with a solution of 

 common sodium phosphate in water. A similar 

 emulsion I have shown to occur in so-called chylous 

 urine, and in certain effusions in the scrotum, termed 

 variously milky hydrocele or lactocele or better lipo- 

 rocele. The serum further contains cholesterine, 

 kreatinine, urea, hippuric and lactic acid in small quan- 

 tities, and at least one, perhaps two, yellow colouring 

 matters are contained in it. In gout, uric acid as 

 urate of sodium and calcium is found in it ; in diabetes, 

 sugar ; in jaundice, biliary colouring matter, or 

 cholophseine ; and in leukocythaemia, formic acid, 

 xanthine and other matters. 



0^ inorganic salts the serum contains sodium chlo- 

 ride, sodium dicarbonate, and calcium phosphate, small 

 quantities of magnesium phosphate, still smaller ones 

 of potassium salts. The chemical operations of the 

 serum (and blood on the whole) employ sodium salts 

 mainly, while those of the muscles mainly choose 

 salts of potassium. We shall see how the function of 



