548 
Vines . — The Proteolytic 
with Na 2 C 0 3 . In view of the great retardation of digestion 
caused by treatment with 5 °/ o Na 2 C 0 3 indicated in the fore- 
going table, I determined to experiment especially with this 
degree of alkalinity, but at a higher temperature : the tem- 
perature upon which I fixed was 50° C. The following are 
illustrative experiments : — 
2. Temperature during period of alkalinity , 50° C. 
(May 30.) Treatment with 5% Na 2 C 0 3 for 45 mm.; digestion much 
retarded. 
(June 1.) „ ,, ,, ,, ijhour; no digestion in 
48 hours. 
Hence it would appear that, in the second case, the digestive power 
had been totally destroyed. 
The following are some further comparative experiments to 
determine more closely the degree and duration of alkalinity, at 
50° C., necessary to destroy digestive action. In each case there was 
a control-tube, the liquid in which was heated to 50° C. for the same 
length of time as the others, but was not treated with Na 2 C 0 3 , though 
diluted subsequently to the same extent as the others : the amount of 
fibrin used in the digestion was -oi grm. 
(a) Treatment with 5 °/ 0 Na 2 C 0 3 for \\ hour; no digestion in 6 
days. 
digestion complete 
in 4 days. 
control ; digestion complete 
in 3-I hours. 
( 6 ) „ „ 5% „ „ 1 ; hour ; no digestion in 5 
days. 
no digestion in 5 
days. 
control ; digestion complete 
in a few hours. 
(c) „ „ 1% „ „ 1 hour; no digestion in 4 
days. 
control ; digestion complete 
in a few hours. 
