1120 



begins. The line I in fig. 



Fig. 1 



1 is found when we raise the current 

 strength immediately after every 

 /\ reading without waiting till the 

 potential has reached a constant 

 value. When now, after a potential 

 of about -j- 0.8 V has been rea- 

 ched, we make the strength of 

 the current fall rapidly, line II 

 in fig. 1 is found. In this case 

 the potentials are much more 

 negative with equal strength of 

 current than when we work with 

 increasing strength of current. Also 



Potential. 



-o-s 



o.o'y 



Fig. 2. 



in cnrrentless condition the electrode is much more negative than 



before the polarisation, viz. — 0.8 V as against — 0.55 V. 



When the strength of the current is not I'apidly increased, but when 



we wait after every increase of 



the strength of the current, till 



the potential has become con- s 



stant, we obtain a line lying 



between the first mentioned. In 



tig. 2 the line for rapid increase 



of the strength of the current 



is given by I, that for rapid 



decrease by II, the line for 



slow increase of the strengtii 



of the current by III. Line III is also found when tiie strength 



of the current is made 

 to decrease slowly. In this 

 last mode of procedure we 

 get from a point on line I 

 to a point of line II, and 

 then the potential rises slowly 

 to a point of line III. In 

 consequence of this the poten- 

 tial as function of the time 

 presents a peculair course, 

 which is represented in figure 

 3. Tlie upmost line was found 

 when the current was rapidly 

 changed from 5 mA tol niA. 



FiK. 3. 



