82 THE BLOOD. 



taken. At such times, the fatty particles of the chyle, 

 added quickly to the blood, are only gradually assimilated ; 

 and their quantity may be sufficient to make the serum of 

 the blood opaque, or even milk-like. 



As regards the inorganic constituents of the blood, the 

 substances which remain as ashes after its complete burning 

 one may observe in general their small quantity in pro- 

 portion to that of the animal matter contained in it. 

 Those among them of peculiar interest are the phosphate 

 and carbonate of sodium, and the phosphate of calcium. 

 It appears most probable, that the blood owes its alkaline 

 reaction to both these salts of sodium. The existence of the 

 neutral phosphate (Na 2 H.PO 4 ) was proved by Enderlin : 

 the presence of carbonate of sodium has been proved by 

 Lehinann and others. 



In illustration of the characters which the blood may 

 derive from the phosphate of sodium, Liebig points out the 

 large capacity which solutions of that salt have of absorb- 

 ing carbonic acid gas, and then very readily giving it off 

 again when agitated in atmospheric air, and when the 

 atmospheric pressure is diminished. It is probably, also, 

 by means of this salt, that the phosphate of calcium is held 

 in solution in the blood in a form in which it is not soluble 

 in water, or in a solution of albumen. Of the remaining- 

 inorganic constituents of the blood, the oxide and phos- 

 phate of iron referred to, exist in the liquor sanguinis, 

 independently of the iron in the corpuscles. 



Schmidt's investigations have shown that the inorganic 

 constituents of the blood-cells somewhat differ from those 

 contained in the serum ; the former possessing a consider- 

 able preponderance of phosphates and of the salts of potas- 

 sium, while the chlorides, especially of sodium, with phos- 

 phate of sodium, are particularly abundant in the latter. 



Among the extractive matters of the blood, the most 

 noteworthy are Creatin and Oreatinin. Besides these, 

 other organic principles have been found either constantly 



