954 R. H. Chittenden—Dehydration of Glucose. 
ach emptied of its contents and then divided into two longitudinal 
halves along the curvatures. One-half, after being cleansed, was 
finely divided and placed in a small beaker with 70 c. ec. of water con- 
taining 0°200 gram of glucose. An equivalent amount of the small 
intestine, similarly cleaned and divided, was placed in a second beaker 
in contact with 70 c¢.¢. of water containing 0°150 gram of glucose. 
In both cases the entire walls, including muscularis and mucosa, 
were taken, since Pavy has indicated that the converting principle is 
situated not on the surface of the mucous membrane, but in the deeper 
part. The two mixtures were then placed in a bath and warmed at 
48°8° C. for nearly two hours; after which they were boiled, crystals 
of sodium sulphate being added to aid the removal of the dissolved 
albumin. The individual filtrates and washings were concentrated 
and finally brought to a volume of 100 ¢.c¢. Of this, 25 c. ¢. were 
used to determine the cupric oxide-reducing power of the solution 
directly, while 50 ¢.¢. of each solution were mixed with sufficient 
ten per cent. sulphuric acid to insure a content of two per cent. and 
then boiled for two hours, in connection with an inverted Liebig’s 
condenser to prevent concentration. The acid solutions were then 
neutralized, concentrated somewhat and finally brought back to a 
volume of 50 c.c. Following are the analytical results obtained 
with the two solutions, the reducing power being determined by 
Allihn’s gravimetric method.* 
STOMACH. 
a. Before treatment with sulphuric acid. 
25 c. c. gave 0°0746 gram Cu=0°0381 gram dextrose x 4=0°1524 gram dextrose. 
b. After treatment with sulphuric acid. 
25 ¢c. c. gave 0:0728 gram Cu=0°0372 gram dextrose x 4=0°1488 gram dextrose. 
INTESTINE. 
a. Before treatment with sulphuric acid. 
25 ¢. e. gave 0:0512 gram Cu==0-0265 gram dextrose x 4=0°1060 gram dextrose. 
b. After treatment with sulphuric acid. 
25 c. ce. gave 00520 gram Cu=0-0269 gram dextrose x 4=0°1076 gram dextrose. 
Here, there is no evidence whatever that the glucose was affected 
by its two hours’ contact with the stomach and intestine of the rabbit 
at 48°8° C., the temperature specified by Pavy as that best adapted 
for the reaction. Certainly the reducing power of the glucose solu- 
tion is essentially the same before and after treatment with sulphuric 
* Zeitschrift fiir Analytische Chemie, 22. Jahrgang, p. 448. 
hel ‘ 
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