Chittenden and Hart — Elastin and the Elastose Bodies. 35 



The entire digestive fluid was therefore neutralized with dilute 

 hydrochloric acid (no neutralization precipitate), and the protoelas- 

 tose at ouce separated by saturation with sodium chloride. The 

 product was purified by repeated precipitation with salt, and after 

 dialysis, the resultant fluid was evaporated to dryness and the 

 residue dried at 110° C for analysis. The product contained con- 

 siderable ash (7'4 per cent.), consisting mainly of calcium phosphate 

 and sulphate, with some oxide of iron. Its composition, seen in the 

 accompanying table, is somewhat different from the protoelastose 

 formed by pepsin-hydrochloric acid, containing as it does a notice- 

 ably lower percentage of carbon. In its reactions, however, it 

 resembles closely the preceding preparations. It is readily soluble 

 in cold water and the solution when heated gives the characteristic 

 turbidity, which disappears as the solution cools. With acetic acid 

 and potassium ferrocyanide, it gives the usual precipitate and also 

 with the concentrated mineral acids, the latter dissolving in an 

 excess of the acid. Unlike the protoelastose previously described, 

 however, it gives with cupric sulphate a precipitate soluble in excess 

 of the copper salt, and with sodium hydroxide no precipitate. In 

 all other respects, its reactions resemble those of the proto body 

 formed in pepsin digestion. 



Analysis of the SooroM Chloride Precipitate— Trypsin Digestion of B. 



Percentage composition of ash-free substance. 



17-02 



16-74 



Average. 



53-05 



7-02 



16-88 



SS-05 



100-00 



In the salt-saturated filtrate from protoelastose, the addition of 

 a little 30 per cent, acetic acid saturated with salt gave a second 



