( 1008 ) 
100 ce. Na,Co, of 0.1°/,. The trypsin dissolved in it with a 
slight opalescence, the solution was not filtrated before it was used. 
To 5 ce. of this solution were added 5 cc. water and 5 ec. CaCl,- 
solution, respectively. 
TAB LEE: ML 
Dede of two 
albumencolumns 
in m.m. after: 
| 
zen 224 hrs. 
Ee hrs. 
1) Trypsin sol. 1/100: 5 c.c. + water: 5 c.c. 3 4 
2) Trypsin sol. 1/100: 5 c.c. + CaClp sol. of 1%: 5 c.c. 9 15 
3, Trypsin sol. 1/100: 5 c.c. + CaClg sol. of 1%9:2'/g cc. + 10 l 
water: 21/5 cc. 
From this experiment it appears that in 2) and 3) where CaCl,- 
solntions had been added to the trypsin-solutions, the albumen 
digestion was considerably greater than in 1), where water had 
been added. We observe that the trypsin itself (1) showed very 
little activity as regards coagulated albumen, though as I observed 
before, 1 gramme of trypsin had been taken upon 100 c.c. Na,Co, 
of 0.1°/, (an addition of an equal volume of water making the 
concentration 1/200). And further that this power was considerably 
heightened under the influences of a 1°/, anda 0.5 °/, CaCl,-solution, 
respectively. 
Still from this result it might not be concluded yet that CaCl, 
had promoted the action of trypsin. And that, for this reason: the 
trypsin-preparations migbt still contain some trypsinogen, which might 
have been turned into trypsin by CaCl,. 
Befure continuing our experiments in this direction, we therefore 
had to settle first whether the trypsin-preparation used, was indeed 
free from trypsinogen. This question could be solved by adding in 
a following experiment also intestinal mucous membrane extract to 
the trypsin-solution and at the same time the boiled extract. | It 
is generally held, and in my opinion absolutely certain (Cf. 3) 
Table Il) that boiling renders inactive the substance in the intestinal 
mucous membrane extract which causes trypsinogen-activation |. 
In order to solve the question whether the trypsin was free from 
trypsinogen or not, it seemed advisable to make a double experiment 
