88 
So far a deviating behaviour has, therefore, only been found for 
iron, nickel, and chromium, hence for metals that have ions of 
different valencies, for this reason it was desirable to examine whether 
the phenomenon would continue to exist when the ratio of concen- 
tration between the different ions in the electrolyte is everywhere 
so, that the metal can coexist in state of internal equilibrinm with 
this electrolyte. This was investigated for iron by boiling a solution 
of Ferro-chloride with iron-powder for a long time in the vessel 
in which the definitive experiment was to be made, leading over 
pure hydrogen at the sametime. The solution thus obtained was 0.6 N. 
The result obtained with this solution was convincing in a high 
A ae a ne a ne 
Fig.10._ 
degree. As fig. 10 shows after anodic polarisation there was nothing 
to be seen of a minimum, and at least qualitatively the iron behaved 
like silver and copper. 
It is now natural to assume that also for nickel and chromium 
the phenomenon can be made to disappear in the same way, about 
which experiments are now being in progress. 
Laboratory for General and Anorg. 
Chemistry of the University. 
Amsterdam, March 27th 1919. 
