992 
elucose, the glucose-percentage of the urine would become equal to 
that of the circulating fluid. Repeated experiments showed that the 
elucose concentrations were exactly the same in both experiments. 
We shall give some of the values obtained. Each experiment was 
repeated at least three times and all gave the same results. 
Jan. 20 to Jan. 26. 1916. - 
1. Rineer-solution containing 0,1 °/, of glucose transmitted from the aorta 
through the kidneys under a pressure of + 50 c.m. Reduction of transmission- 
fluid 0,098 °/5. Reduction (expressed in glucoseconcentration) of the left kidney 
6,095 °/, right kidney 0,095 9/5. 
2. Circulation of Rrinaer-solution containing exactly. 0,05 °/) of glucose, from 
the aorta. Pressure 60 ce. of water. Reduction of urine to the left 0,05 0/,, to 
the right 0,045 9/o. 
3. Circulation from the aorta with pure Rincer-solution. The urine shows no 
reduction. 
These results formed, as it seemed, a reliable foundation for 
further researches. It was now expected that on serum being added 
to the Ruinexr-fluid containing glucose, the free glucose would be 
entirely or partially bound; in other words that the reduction 
capacity of the ureter-fluid would be smaller than that of the circu- 
lation-fluid. 
3. The permeability of the kidneys to glucose when it is dissolved 
in a mixture of serum and Rincer-/lucd. 
2.4. Series of Experiments. 
For these experiments horse’s or neat’s serum was diluted with 
a 2-, 3-, 4- and 5-fold quantity of RiNGeR-fluid to which mixtures 
in every instance a known quantity of glucose was added. The 
secretion of ureter-fluid took place very slowly, but could be pro- 
moted by the addition of urea. 
We subjoin a few of the many experiments. 
1. Frog’s kidney through which flows a fluid consisting of 50 c.c. of horse’s 
serum + 150c.c. of Ringer + glucose + urea. Reduction of this mixture 0,17 °/o, 
reduction urine 0,086 °/,. Consequently 0,09°/) of glucose has been kept back 
(= the quantity of glucose in normal horse’s serum). 
2. The fluid consists of 75 c.c. of neat’s serum + 225 c.c. of Rincer + glucose 
+ urea. Reduction of the transmission fluid 0,21 °/o, reduction of the urine only 
0,12 0/,, to the right, 0,105 °/o. to the left. 
3. The fluid consists of 60¢c. of horse's serum + 240 c.c. of Ringer + glucose 
+ urea. Reduction of the transmission-fluid 0,14 °/,. Reduction of the urine to the 
right 0,03°/9, to the left 0,028 /. Hence at a 5-fold serum dilution 0,11 0/, 
of glucose in still kept back. 
In the same way 0.07 °/p of glucose was kept back at a 6-fold, 0.06°/, at a 
7-fold dilution but at an 8-fold dilution next to nothing. 
