Stiles and Jergensen.—Studies in Permeability. /. 361 
chloride (Merck’s reagent). In water solution ferric chloride gradually 
hydrolyses into ferric hydroxide and hydrochloric acid. Controls were 
therefore used of solutions of the same composition but in which potatoes 
lime in hours. 
10. Potato in Mixtures of ^- 00 Cu 50^with various added amounts of Aluminium Chloride 
Fig//. Bean roots in ~~ Q Gu SO 4 solution and m mixtures of ^qCvSO4 
with AlGl 3 . 
were not placed. Allowing for the rise in conductivity which takes place 
in these solutions owing no doubt to the production of hydrogen ions, 
and which is considerable in the solutions containing ferric chloride in 
greatest amount, the curves representing the results obtained are as shown 
B b 
