86 
rapidity, and does not present the potential of before the cathodic 
polarisation again until after nearly five minutes. As the whole course 
occupied so much time, we have made the box with the film execute 
some revolutions, so that the successive pieces have come above 
each other on the photo. 
It is of importance to state here that Ranrerr *), who has also 
carried out experiments on this subject, found a more negative 
Ni 
zer 
341SEC 
Fig.5. 
potential for nickel after anodic polarisation in agreement with us, 
but after cathodic polarisation a much more positive potential. This 
is in conflict with what was found by us, and must probably be 
attributed to a mistake in the arrangement in Raarerr’s investigation. 
For on earlier occasions the phenomenon photographed in fig. 5 
was always found by Smits and Losy pe Bruyn and now by us. 
As it was of importance to include also a few other metals in our 
considerations, we have also investigated silver and copper immersed 
in a silver-nitrate, resp. copper sulphate solution with the following 
result. 
The photo fig. 6 is a reproduction of the potential course of a 
silver electrode with an area of 42 mm.’ in a 0,1 NAg NO*-solution 
after anodic polarisation witha density of current of 0,333 Amp./cm.’, 
Fig.6. 
1) Zeitschr. f. phys. Chem. 86, 567 (1914). 
eae denkend 
