76 
of water at ordinary temperature for two or three hours. Ten cubic cen- 
timeters of this malt infusion were then added to each of the starch 
preparations, which were kept at from 60 to 65° C. The starches were all 
dissolved in the following order: Sweet potato, 6 to 8 minutes; common 
potato, 12 to 15 minutes; wheat, 60 to 90 minutes; maize, 90 to 120 minutes. 
On diluting the starch in a subsequent series, using the same amount 
of malt infusion, the time of solution was much reduced, but followed the 
same relative order. In another series a larger amount of malt was used, 
and the time of solution was still shorter; for instance, the sweet-potato 
starch was completely dissolved in 2%, minutes; potato starch, 34 minutes; 
wheat, 30 minutes; maize, 38 minutes. These results indicate very con- 
clusively a decided difference in the behavior of these common starches 
toward diastase. 
Similar experiments were then planned with these starches, with the 
addition of rice starch, and ptyalin, one of the active principles of the 
saliva. 
At first raw starch was employed, but it seems to suffer little or no 
change even after some hours. Boiled starches, prepared as already de- 
scribed, received each two cubic centimeters of saliva and were kept ata 
temperature of 40°. After six minutes the potato starch no longer gave 
any iodine reaction; the sweet potato required 135 minutes; the maize, 145 
minutes; rice, 385 minutes; wheat, 400 minutes. By increasing the 
amount of saliva to six cubic centimeters the following results were ob- 
tained: Potato, 8 minutes; sweet potato, 7) minutes; maize, 90 minutes; 
rice, 165 minutes; wheat, 170 minutes. 
On increasing the temperature to 60° potato starch was almost imme- 
diately dissolved in two minutes; sweet potato, 25 minutes; maize, 35 min- 
utes; but rice and wheat were not wholly converted in five hours, indicat- 
ing that a continuation of this temperature for any considerable time 
destroys the activity of the ferment. 
These results were no less striking than those obtained from diastase, 
although the order of conversion is changed somewhat. Wheat required 
about SO times as long for complete solution as potato. 
The experiments with pancreatic ferments were carried out in the 
same way as already described, so far as the staches were concerned. 
Using commercial preparations of pancreatin at the rate of .2 grams to 
.2 grams of the starches gave these results: Potato starch was dissolved 
in 58 minutes: sweet potato, 317 minutes: maize, 337 minutes; rice and 
