270 Wisconsin Academy of Sciences, Arts, and Letters. 
tar with clean sand, and placed in a test tube with sufficient gly¬ 
cerine to cover it. Similar glycerine extracts of the intestine and 
the pancreas were made, and the test tubes were allowed to stand 
for two days in order that the glycerine might extract the en¬ 
zymes. 
Peptic Digestion 
Three test tubes were set up, containing, respectively: (1) 1 
gram egg albumen, and 20 drops of glycerine extract of the 
stomach; (2) 1 gram egg albumen and 20 drops of solution of 
commercial pepsin; (3) 1 gram egg albumen. The three tubes 
were filled with 10 cc. of a 2% solution of hydrochloric acid and 
placed in a bath at a temperature of 35 to 40° C. for one hour. 
In test tube (1) the albumen swelled up into large flakes which 
soon disappeared, and a practically clear solution was obtained at 
the end of the hour; in tube (2) the flakes of egg albumen dis¬ 
appeared less rapidly, and in tube (3) they disappeared still more 
slowly. The contents of the test tubes were then filtered and neu¬ 
tralized with sodium hydroxide. In tubes (1) and (2) a heavy 
flocculent precipitation was formed upon addition of the base; in 
tube (3) no such precipitate was formed. This precipitate prob¬ 
ably consisted of acid-albumens. An excess of sodium hydroxide 
was then added to the contents of each test tube, and then a drop 
of very dilute copper sulphate. A faint rose reaction in tubes 
(1) and (2) showed the presence of proteoses and peptoses, 
whereas the absence of such a reaction in tube (3) showed the 
absence of these products of digestion. 
The reaction of the contents of the stomach of a large pickerel 
on litmus paper was tested and found to be decidedly acid. Eight 
drops of a 20% solution of sodium hydroxide were required to 
neutralize it. 
Pancreatic and Intestinal Digestion 
With proteins. Four test tubes were set up, containing, res¬ 
pectively: (1) 0.5 gram egg albumen and 20 drops glycerine ex¬ 
tract of intestine; (2) 0.5 gram egg albumen and 20 drops gly¬ 
cerine extract of pancreas; (3) 0.5 gram egg albumen and 20 
drops of commercial pancreatin solution; (4) 0.5 gram egg al¬ 
bumen. Ten cc. of 1% solution of sodium carbonate were then 
placed in each tube and the tubes were placed in water at a 
temperature of 35-40° C. for one half hour, at the end of which 
time the egg albumen had gone into solution completely in all the 
