360 Stiles and Jergensen.—Studies in Permeability. /. 
three hours the different solutions behaved very differently, as indicated by 
the curves in Fig. 8. The more aluminium chloride present, the greater 
the apparent depression of the exosmosis, so that in the solutions containing 
most aluminium there is at first a fall in conductivity. 
A similar result was obtained when bean roots were used in place of 
potato (Series 9). 
These measurements were repeated several times with a constant result, 
and the same result was obtained when similar mixtures were made with 
N 
^ copper sulphate, both when potato (Series 10) and bean roots 
immersion of the bean roots. 
As will be noticed from the curve shown in Fig. 1, aluminium chloride 
itself produces a little rise in conductivity. Different strengths give little 
difference in this respect. 
At first sight it would appear, then, that by this method a definite 
antagonism between copper and aluminium is exhibited. This may be the 
explanation of the results obtained, but, as the next series will indicate, 
other explanations are possible. 
Series 13. A series similar to the last was made with potato in copper 
sulphate solution, to which was added various strengths of ferric 
r 2000 
