98 Chittenden and Allen—Influence of various Salts 
power. The influence of boracic acid on pepsin-hydrochlori¢ acid is — 
seen from the following experiments: 
: 
- 
: 
d 
Undigested Fibrin. Relative proteo- 
H; BOs. residue, digested. lytic action. 
0 0 2395 gram. 76°05 per cent. 100°0 
01 per cent. 0°2252 71768 1021 
0 0°2049 (Gin! 100-0 
0°5 0°1875 81°25 102-2 
3°0 01729 82°71 1042 . 
60 01445 85°55 107°6 
Evidently then, the action of borax consists simply in withdrawing 
from the pepsin the hydrochloric acid of the gastric juice. The low 
digestive power of pepsin and boracic acid is shown by the following 
experiment : 
A, B. Cc. D. 
H.0O sol. pepsin ----- 50 ce 50 c.¢. 50 cc. 50 ¢. ¢. 
HCl 0:2 per cent..... 50, 0 0 0 
HeBOpeese ees ae eee 0 0-2 gram. 0°3 gram. 05 gram. 
HORS zeetesteis oe 0 50 ec. 50 ee. 50 ¢.¢. ’ 
100 100 100 100 
01¢HCl 024HsBO; 034H,BO, 05%H;BO, | 
To each, was added 1 gram of purified fibrin, after which the mix- 
tures were warmed at 40° C. for 2 hours. Following are the results. 
A, B. C. D. 
Wt. of undigested residue ---- -- 2 071180 09615 0°9705 0°9620 
HBerjicent; digested 2222 255-22+222 88:20 3°85 2°95 3°80 
Ammonium oxalate. 
With this salt the following results were obtained : 
ey 
Undigested. Fibrin Relative proteo- 
(NH4)262044+2H20. residue. digested. lytic action. 
0 0°3254 gram. 67°46 per cent. 100-0 
0°610 per cent. 0°3579 64°20 95:1 
0:025 0°3627 63°73 94°6 
0-1 0°3920 60°80 901 
0°5 0:9049 9°51 14:1 
0 0°3098 69°02 100°0 
1:0 0°9958 0 42 6°6 
As to the cause of this retarding action, it is probable, that, as in 
the case of borax, the oxalic acid of the salt is displaced and the 
ferment compelled to act with the acid thus liberated. But if we 
compare the results of the present series with those of the preceding, 
