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LXVII. On the Thermal Phenomena of the Galvanic Pile, and 

 Electromotive Forces. By E. Edlund. 



[Concluded from p. 441.] 



E will now apply to Favre's experiment the theoretical 

 representation No. 2 ; and we will denote by E the 

 electromotive force of the series, and by e the electromotive 

 force of polarization in the voltameter, and assume that the 

 resistance in the voltameter can be neglected in presence of 

 the resistance of the series and rheostat. 



(a) Calorimeter No. 1 including the series and the rheostat, 

 without a voltameter. — While, in each element, an equivalent 

 of zinc dissolves, the chemical processes develop a quantity of 

 heat which we will call k ; at the same time the electromotive 



force consumes a quantity of heat which is equal to 23900 - , 



wherein d signifies, as before, the electromotive force of a 

 Daniell element. The quantity of heat generated in the series 



M 



and the rheostat is qw = — E. For the Daniell element we 



M E 



have 23900 = ~d, from which we get gw — 23900 -y . Putting 



together the action of these three sources of heat, we obtain 

 the quantity k of the chemical heat, which alone, in this case, 

 determines the deflection of the calorimeter. 



(b) Calorimeter No. 1 including the series, the rheostat, and 

 the voltameter. — The quantity of heat expended for the chemi- 

 cal decomposition in the voltameter may be named a. The 

 total amount of chemical heat is therefore now k — a. In the 



E 



series the quantity of heat consumed is 23900 -y ; but in the 



e 

 voltameter a quantity of heat 23900-^ is generated, because 



the electromotive force of polarization acts in the opposite 



direction to the current. The galvanic heat developed in the 



E— e 

 conductors is = — — — x 23900. Putting together the action 



of all these sources of heat, we get the sum k — a, which in 

 this case the calorimeter indicates. 



(c) Calorimeter No. 1. containing the series and the rheostat, 

 and the calorimeter No. 2 containing the voltameter. — In No. 1 

 a quantity of chemical heat = k is developed ; but during the 



E 



same time a quantity of heat = 23900 -=- is consumed bv the 



