[clark] 



CAPILLARY ELECTROMETER 



81 



opening K2, or we may obtain the final potential of the system when 

 it settles down after K2 is opened. 



Using El = -^ and E2= ^ 

 Ci C2 



we have the potential of the condenser system at any instant 



^^^i±Sl = Sl^l. 2715, etc. (16) 



C1+C2 C1 + C2I 



This equation plotted follows the general character of the experi- 

 mental curve, but the amplitude is considerably greater. This is to be 

 accounted for, probably in the emf of the concentration cell caused by 

 the transport of ions in the acid solution due to the passage of electricity 

 through it. 



For making or breaking the circuit in this and other determina- 

 tions of charge and discharge curves a Webster chronograph^ was 

 used. The potentiometer connections were led to a non-inductive 

 resistance through one key of the chronograph. The self-inductance 

 (•81 henries), and the electrometer and condenser in parallel, were 

 connected to the terminals of the non-inductive resistances through 

 the second key of the chronograph. The falling weight opens the two 



Webster. Physical Review (I), VI, 297, 1898. 



