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ROYAL SOCIETY OF CANADA 



modulus of electricity; at least, this is true for the materials here 

 tested. 



This work only concerned currents, the actions of which were of 

 short duration. Perhaps, after a current has been passing through a 

 wire for a long period, of months or years for instance, there may 

 be an effect on the modulus; but such changes are liable to occur, 

 and do occur, if the material is left alone without any current in it. 

 It would be difficult to distinguish and measure the effect by the 

 current from the same effect by other courses. 



For currents of short duration, the probability is that in all 

 materials the same results would be obtained as were obtained here, 

 viz., that the current has no effect whatever in altering the modulus 

 of elasticity. 



The values of the modulus found for the materials tested are given 

 in the following table: — 



I desire to thank Dr. Barnes for his advice and help in carrying out 

 these experiments. 



