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Mr. E. Wilson. Aluminium as an Electrode 



Tliis brings us to the effect of temperature upon potential for a 

 given current. The cell containing the aluminium, plate formed in 

 alum solution above referred to was placed in an oil bath, the tem- 

 perature of which could be varied. The current was that due to 

 56 storage cells, through a considerable external resistance, about 

 650 ohms during heating, and 2280 during cooling. There was an 

 excess of alum in the cell, and the solution was kept saturated. The 

 variation of potential between the aluminium and carbon electrodes 

 was noted, as also the temperature of the cell. The results are 

 given in Table III. 



Table III. 



We see that as the temperature of this cell rises from 13*5 to 70 C., 

 the potential difference falls from 30 to 3 volts. The experiments 

 already made on the resistance of the electrolyte will only account for 

 0-043 volt at 13-5 C., and 0'025 volt at 57 C. with the currents 0-124 

 and 0-141 ampere as given in Table III. The conclusion is that 

 temperature has an effect upon the apparent high resistance of an 

 aluminium plate and its film, the subject of this paper. This points 

 to the fact, that in practice for high apparent resistance, it would be 

 necessary to cool or circulate the electrolyte with such dissipation of 

 energy, that the cell would otherwise acquire a high temperature. 



