222 INFLUENCE OF BILE AND BILE SALTS 



Neutral ........... 0.3896 gram 61.04 per cent 100.0 



Proteids combined with acid 



One-eighth saturated (0.006 % HC1) 0.3951 60.49 99.0 



One-sixth " (0.008% HC1) 0.4798 62.02 86.2 



One-fourth " (0.012% HC1) 0.6030 49.70 81.4 



One-half " (0.026% HC1) 0.6609 34.91 67.1 



Wholly " (0.060% HC1) 0.9327 6.73 11.0 



Pig's Pancreatic Juice. 



Neutral .......... 0.1966 gram 80.34 per cent 100.0 



Proteids combined with acid 



One-sixth saturated (0.003% HC1) 0.2110 78.90 98.2 



One-fourth " (0.004% HC1) 0.2664 78.46 91.4 



One-half " (0.009% HC1) 0.3281 67.19 83.6 



Wholly " (0.018 %HC1) 0.6664 44.36 66.2 



Experiment 46. With extract of ox pancreas. 25 c.c. of the neutral extract 

 .required 19.7 c.c. 0.4 per cent salicylic acid to combine with the proteids 

 present 



Neutral ........... 0.4668 gram 63.42 per cent 100.0 



........... 0.4894 61.06 95.6 



Proteids combined with acid 



Completely saturated (0.157% acid) 0.9860 1.40 2.6 



(0.157% acid) 0.9874 1.26 2.8 



Half " (0.078% acid) 0.8443 16.67 29.1 



" " (0.078% acid) 0.8376 16.25 30.4 



In considering the results of the three preceding experi- 

 ments it is to be remembered that in no one of the digestive 

 mixtures was there any free acid present, hence such effects 

 as are produced come solely from the influence of the com- 

 bined acid. Of the latter, even a few thousandths of one per 

 cent suffice to exert an inhibitory influence on proteolysis, and 

 with a sufficient amount of combined acid alone, even with a 

 weak organic acid, proteolysis may be almost completely 

 checked. We fail to see, therefore, how the addition of acid to 

 a neutral pancreatic juice can increase the digestive power of 

 the solution. 



