﻿346 Prof. Trouton and Mr. Searle on Leakage Currents 



Some further determinations are given, obtained with the 

 direction of the current reversed — curves IX., X., and XI. 

 Here the condition of sensitiveness is rapidly altering so that 

 the departure from Ohm's law is masked to a large extent. 



Fig. 4. 

 Curves connecting Current and Impressed E.M.F. 



It will be seen, however, that the curves are all convex to the 

 E.M.F. axis, as they should be were the resistance to alter 

 as supposed. Curve XII. was obtained with the cells reversed, 

 but the order of application was that originally used. It is 

 also in general agreement with the others. 



It is obvious from the trend of the curves that the sup- 

 position of a large back-E.M.F. of constant value is geo- 

 metrically inapplicable, quite apart from the question of 

 how to account chemically or otherwise for one of such a 

 large amount as that required to explain the reversal effects, 

 and from the fact that the usual 1*4 volts are always 

 observable. 



It thus appears to be necessary to fall back on the supposition 

 of a variable resistance. 



