24 EVIDENCE NOT RECOGNISED. 



product of the electromotive force of the elements multiplied 

 by the number of elements electrolyzed. The inference, 

 however, was not drawn. Again, it was well known that 

 heat was generated by a current in a conductor, and it was 

 generally believed that the heat was proportional to the 

 electric action expended, expressed by Ohm as the product 

 of the electromotive force multiplied by the current, but no 

 definite experiments had been made to establish this ; nor 

 had there been any suggestion of the inference which 

 immediately followed, that the heat developed in the entire 

 circuit of the battery would be proportional to the same 

 product which expressed the electric action of the battery in 

 overcoming resistance, the number of equivalents of the 

 elements combined multiplied by the electromotive force of 

 these elements. Still less had it been suggested that this 

 definite development of heat, associated with the chemical 

 combination effected by the electrolysis of definite 

 quantities of definite elements, was identical with the 

 quantity of heat that would be produced by the chemical 

 combination of the same elements — the heat generated by 

 combustion. 



The practical possibilities apparently underlying Stur- 

 geon's invention as a prime-mover which might displace the 

 steam engine, secured attention to the exclusion of the 

 philosophical significance of the actions revealed. How to 

 increase the power and economy of the engines ? was the 

 question for the time. The heat generated by the currents 

 in overcoming the resistance of the conductors, and that 

 generated by the friction of the working parts, being looked 

 upon as necessary evils to be minimized, rather than as keys 

 by which the most general law in the universe was shortly 

 to be revealed. 



