( 417 ) 
As to the amount of chlorine my statements agree with those 
of Nencxr and Sreser. While the latter found in five determina- 
tions, either 0.47 °/) or 0.48 ,/?, I found 0.49 °/,. To the reasons, 
given by these investigators, for the opinion, that chlorine forms an 
element of the molecule of pepsin I may add another. The pepsin 
that was separated either directly by dialysis, or first by ammonium 
sulfate, was then dissolved, in as great a concentration as possible, 
at 37° C. in 1 0/, oxalic acid and precipitated from this solution by 
dialysis into distilled water. This precipitate rapidly digested fibrin, 
when dissolved in oxalic acid. If now the chlorine found in the 
pepsin, which was separated out of the solution in hydrochloric acid, 
did owe its origin to hydrochloric acid that was not sufficiently 
washed out, then we might expect, that in the substance, separated 
out of oxalic acid, the clorine could no more be found. Nevertheless 
chlorine could repeatedly be shown very distinctly in this. 
The results of the analysis of six preparations follow here. 
C H N S 
52.13 7.06 
| 14.13 
I 52.06 7.19 1.66 
| | 14.33 
51.81 7.09 Pepsin precipitated by dialysis 
Bi 51.92 7.14 14.50 of the gastric suice. 
TUT: 52.13 7.01 14.58 1.63 
ny. 51.61 6.93 14.572 1.61 
¥. 52.32 7.16 14.75 1.83) Pepsin precipitated by half satur- 
ating the dialysed gastric suice 
Val: 52.01 7.02 14.65 | with ammoniumsulfate. 
That the amount of sulfur in V was found a little higher than 
in the other preparations, may perhaps be attributed to contamination 
with ammonium sulfate. This supposition is perhaps supported by 
the amount of nitrogen. With 0.2°/, S derived from (NH,). SO, 
corresponds 0.175 °/) N. So the amount of N whould become 14.575 UA 
and would better agree with the amount of nitrogen of the other 
preparations. 
The quantity of preparation VI was not sufficient also to deter- 
mine the amount of sulfur. The amount of ash is not, as with all 
the other preparations, taken into account here. Herein lies however 
no objection of any significance, because the amount of ash was 
