I9I2] 



Grover Tracy and William J. Gies 



A71 



vvith pepsin and collagen (third series). Proteases evidently are 

 able to increase hydrophilia in both acid and alkalin media.^^ 



TABLE 8. 



THIRD SERIES OF EXPERIMENTS 



With Collagen and pepsin in 0.025 or 0.05 per cent. hydrochloric 



acid Solution. 



9. Conditions of the ninth experiment : Same as those of No. 

 I {first series), except that finely divided collagen (2 grams) from 

 Achilles tendon (oxen) was substituted for fibrin, 0.05 per cent. 

 hydrochloric acid Solution (instead of o.i per cent.) was used, and 

 the experiment continued six hours. See Table 9. 



TABLE 9. 



10. Conditions of the tenth experiment: Same as those of 

 No. 9, except that the concentration of the pepsin product in the 



" We are now studying the activity of proteases, in this respect, in neutral 

 media. 



" Slight digestion. 



