227 
Hind.— Studies in Permeability. Ill . 
Nitric Acid. 
Series 3.— Conductivity measurements were made of the external 
solution, as in Series i, when potato discs were immersed in nitric acid 
N N N N 
solutions of concentrations , , , . 
1000 2000 3000 10000 
The accompanying- figure (Fig. 2) shows that the result with nitric acid 
is similar to that obtained with hydrochloric acid. 
Series 4.-— Experiments made with the electrometric method of 
measurement, to determine the rate of absorption of the hydrogen ion from 
N 
Fig. 3. Potato in Nitric Acid. 
1000 
nitric acid solutions, show that the kation is absorbed rapidly, as in the case 
of hydrochloric acid. The curve shown in Fig. 3 indicates the rate of 
absorption of the hydrogen ion when 
N 
nitric acid was used. 
1000 
