on the Proteolytic Action of the Pancreatic Ferment. 111 
Cupric sulphate. 
With this salt a more energetic retarding action is to be noticed, 
than in the case of the proteolytic ferment of gastric juice; 0°1 
per cent. of the salt causing a retardation in proteolytic action of 
65°7 per cent. as compared with a retardation of 38°8 per cent. in the 
case of pepsin. 
Undigested Fibrin Relative proteo- 
CuSO4+5H20. residue. digested. lytic action. 
0 0°5035 gram. 49°65 per cent. 100°0 
0°005 per cent. 0°5027 49°73 10071 
07025 075320 46°80 94:2 
0°050 0°5856 41°44 83°4. 
0°100 0°8295 17°05 34°3 
Lead acetate. 
With this salt the following results were obtained, agreeing essen- 
tially in the smaller percentages, with those obtained with cupric 
sulphate. In the presence of 0°1 per cent., however, retardation is 
far less than with the same percentage of cupric sulphate; 0°5 per 
cent. completely stops proteolytic action. 
Undigested Fibrin Relative proteo- 
Pb(CyH302)9+3H20. residue. digested. lytic action. 
0 0°4562 gram. 54°38 per cent. 100°0 
0-005 per cent. 0°4655 53°45 98:2 
0:025 0°5391 46°09 84°7 
0°050 0°5660 43°40 79°8 
07100 0°6410 35 90 66°0 
0°500 1:0 0 0 
Stannous chloride. 
This salt, in conformity with its action on the amylolytic ferment 
of saliva, causes very decided retardation in the proteolytic action 
of trypsin, requiring but a very small amount of the salt to com- 
pletely stop the action of the ferment. 
Undigested Fibrin Relative proteo- 
SnClg. residue. digested. lytic action. 
0 0°3875 gram. 61°25 per cent. 100°0 
0°0005 per cent. 0°4495 55:05 89°8 
0°005 0°5370 46°30 15:5 
0°025 1:0 0 0 
Arsenious oxide. 
Schiifer and Béhm have experimented with arsenious acid, study- 
ing its influence on the proteolytic action of a glycerine infusion of 
* Abstract in Jahresbericht fiir Thierchemie, 1872, p. 363, 
