41 
aqueous solution of iodine C3^anide containing 0.9945 milligram of the 
substance, was allowed to act on 5 cc. of a clear solution of lipase for 
24 hours at the above-named temperatures, the experiments being car- 
ried on in glass-stoppered flasks. At the end of this time, 10 cc. of 
N/20 ethyl butyrate were added to each flask. These were then allowed 
to stand 24 hours at ordinary temperature and were then titrated with 
N/10 sodium hydroxide, with the following results: 
TEMPERATURE, 10° C. 
Name of substance. 
Cubic centime- 
ters of sodium 
hydroxide 
required. 
Per cent of 
hydrolysis. 
Water (control) 
3.65 
73 
Iodine cyanide 
.80 
16 
Do . 
.75 
15 
TEMPERATURE, 40° C. 
Water (control) 
Iodine cyanide . 
Do 
2. 90 
.00 
.05 
58 
0 
1 
It is evident, therefore, from these results, that at 40° C. the fer- 
ment is completely destroyed b}^ this amount of iodine cyanide, whereas 
at 10° C., with the same amount of iodine cyanide, it retains more 
than one-fifth of its original activity. 
