819 



almost constant potential of —0.55. Also the ciirominni of Gold- 

 scHMiDT sometimes got tliis value, sometimes it remained more 

 positive. As an example a series of observations has been extensively 

 given in table I. The solution used was at first feebly acid, generation 

 of hydrogen took place, and the solution assumed a green colour by 

 formation of chromic sulphate. 



TABLE I. Potential. 



The electrode 2 had a very tluctuating potential after 3 days, 

 the other potentials approach to a pretty constant value, which 

 amounts to about — 0.53 V for this series of observations. 



The same phenomenon was met with for all the observations. In 

 table 11 the means of the potentials of all electrodes of eleciroly- 

 tical chromium have every time been given. Always two or more 

 days had elapsed between the measurements. 



The mean of all these 136 observations is — 0,55 V. Accordingly 



TABLE n. 



Nr. 



Potenti al. 



