85 
however, almost entirely disappeared again after a minute. We will 
point out here that a small part of the potential in negative direction 
n . + — — 1 
ee SS enn a re ee rn RR 
FE 4 
=e oe he eS Se ee ot SRI Se Bcc ee 
“+83 mV 
Fig.3. 
kb ~ _ _ _ = ee a eee - _ ee a ee | 
is the consequence of the decrease of concentration in the boundary 
layer during the cathodic deposition of the metal. 
As it had appeared before, as has already been mentioned, that 
nickel, though much more inert, showed the same phenomenon as 
iron, the same experiments have been made with nickel as with 
iron, in which the following result was obtained. 
~i2.mV. 
Fig.4. 
Fig. 4 gives the course of the nickel electrode with an area of 
80 mm.” in a solution of '/,, N NiSO, after anodic polarisation with 
a current density of + 0.075 amp./em., from which appears that 
here the saine phenomenon is seen as for iron; the potential of the 
metal becomes more negative after anodic polarisation, and after 
having reached a minimum value, it slowly returns to the original 
value of before the anodic polarisation. The phenomenon is the same 
here as for iron, but it takes place here with much less rapidity. 
In fig. 5 the result is recorded of the determination of the poten- 
tial difference for nickel after cathodic polarisation with the same 
current density. 
The nickel is at first pretty greatly disturbed in base direction, 
the potential is about 240 m.V. more negative than before the catho- 
dic polarisation, but becomes less and less negative with decreasing 
