Galvanic Pile, and Electromotive Forces, 431 



rent, the electromotive force consumes a quantity of heat ex- 

 actly equal to the quantity generated by the current in over- 

 coming the resistance of the galvanic conduction. The heat- 

 consumption of the electromotive force is accordingly equal to 

 gw ; yet it does not hence follow that it is not also equal to kw, 

 or that gw and Jew have not the same magnitude. 



If only a single electromotor is inserted in the closed circuit, 

 keeping the same notation as before, we have 



gw = m 2 lt = M. 1 ftit; 



therefore in unit time a quantity of heat is consumed which is 

 proportional to the product of the electromotive force and the 

 intensity of the current. Thus, during the solution of one 

 equivalent of zinc, the total amount of heat gw consumed by 



M 



the electromotor = — E. This holds, even if / be changed — 



in ° 



that is, even if the current-intensity be increased or diminished. 

 Are two electromotors E and W acting in the same direction ? 

 then in unit time the total heat-consumption in both must be 

 M(E + W)i /} if ij denotes the intensity of the current produced ; 

 hence, evidently, MEi, is consumed in the former, and ME'z, 

 in the latter. When E is greater than E' and the one elec- 

 motor acts in the opposite direction against the other, the total 

 quantity of heat consumed becomes M(E— W)i /n if % n denotes 

 the current-intensity. In the first electromotor the quantity 

 MEi y of heat is now consumed ; but this is greater than the 

 total quantity generated by the current in consequence of the 

 galvanic resistance. In the other electromotor, therefore, a 

 quantity of heat equal to ME / i // must be generated. Conse- 

 quently, when the current traverses the electromotor in the 

 same direction in which the electromotive force acts, a quan- 

 tity of heat is consumed which is proportional to the product 

 of the electromotive force and the current-intensity; but if 

 the current goes in the contrary direction, just as great a 

 quantity of heat is produced instead*. 



From this it is evident that these two ways of considering 

 the subject agree in one respect, namely that, according to both, 

 the sum of the heat which the current produces upon the 

 whole is equal to nil ; but in the one case the heat produced 

 in the pile by the chemical processes is regarded as con- 

 veyed to the different parts of the circuit ; while in the other 

 heat is supposed to be generated by the current everywhere 

 in the circuit ; yet the total quantity of heat produced is equal 



* The unitarian view of the nature of electricity leads direct to the 

 same result. See"Theorie des phenonienes electriques," p. 45 (K. Ve~ 

 tenskaps Ah. Handl, Bd. xii. No. 8 : also Brockhaus, Leipzig). 



