( 740 ) 
b. Action on gelatine. 
Following the same method as was applied to white of egg, the 
action on gelatine was examined next. The gelatine which we used, 
was prepared by dissolving 10 gr. in 100 ce. of warm water; the 
free acid was then neutralised and a little thymol, with a little 
gentian-violet-solution added. The little pieces of glass tube, placed 
in the liquid mass, filled of their own accord. After the mass had 
gelatinised around and in the tubes, the latter were lifted out, cleaned 
and if needful the protuding gelatine cut off at the ends. *) As the 
gelatine is liquid at 38° and would consequently run from the tubes, 
the experiments were performed at room-temperature. 
In the following summary the results are given. 
The actual figures are omitted for want of room. 
Ist. that intestinal juice alone digests neither gelatine nor white 
of egg; 
2nd, that intestinal juice freed from bacteria and afterwards 
mixed with the bacteria, originally present in the juice, is also not 
capable of digesting gelatine. 
3rd, that pancreatic juice, mixed with water, only becomes active 
after a considerable time; this may be ascribed to the circumstance 
that the zymogen is gradually transformed into trypsin ; 
4th that after 18 hours, within which time neither pancreatic 
juice alone, nor the intestinal juice alone is able to dissolve gelatine, 
the mixture of both had caused a considerable amount of solution. 
5th. that this is equally the case whether the intestinal juice is 
filtered or not. 
Gt, that pancreatic juice, mixed with boiled intestinal juice, shows 
no activity after 18 hours, but it becomes active after 48 hours, 
probably for the reasons stated under 3°. 
7th. that the action cannot in any way be attributed to bacteria. 
We have therefore shown that intestinal juice with pancreatic juice 
behaves precisely in the same way in relation to gelatine as in 
relation to coagulated white of egg. 
c. Action on starch. 
The digestion of starch was studied in the same way as that of 
white of egg and gelatine. Arrowroot starch was chosen, as in 
1) Care should be taken when preparing the gelatine mass, not to heat too strongly 
and for as short a time as possible; otherwise gelatinisation does not readily take 
place. 
ee TP 
