496 OHM ON THE GALVANIC CIRCUIT. 



and then evidently the action terminates by a total separation 

 of the constituents, the entire mass of the one passing to the 

 one end of the portion, and the entire mass of the other consti- 

 tuent being impelled towards the other end of this portion ; or 

 such a relation takes place between the forces in action, that the 

 forces opposing the separation ultimately maintain the decom- 

 posing force in equilibrium ; from this moment no further 

 decomposition will occur, and the portion will be, in a remark- 

 able state, a peculiar distribution of the two constituents oc- 

 curring, into the nature of which we will now inquire. If 

 we call Z the decomposing force of the current in any disc of 

 the portion in the act of decomposition, Y the magnitude of 

 the reaction by which the neighbouring discs ojjpose the de- 

 composition by the electric cun-ent, and X the force of the 

 coherence of the two constituents in the same disc, then evi- 

 dently the state of a permanent distribution within the supposed 

 portion, will be determined by the equation 



X + Y = Z; 



and it is already know'n, from the preceding paragraph, that 



^ ^otz + l3{l—z) ' 



d It 

 or if we substitute x w -r- for S, 

 a ic 



_, ^ du . ,, , m B — net 

 X=4xw-i — .tz{l—z) 



dx ' ^ ' a.Z+ ^ {I—Z)' 



Before w"e proceed further, we wdll add to what has been 

 above said the following remarks. At the Umits of the por- 

 tion in question, we imagine the circuit so constituted, that 

 insuperable difficulties there oppose themselves to any further 

 motion ; for it is obvious that otherwise the two extreme strata 

 of both constituents, which it is evident could never of them- 

 selves arrive at equilibrium, would quit the portion in which 

 we have hitherto supposed them, and either pass on to the 

 adjacent parts of the circuit, or from any other causes separate 

 entirely from the circuit. We will not here follow the last- 

 mentioned modification of the phsenomenon any further, al- 

 though it frequently occurs in nature, as sufficiently shown by 

 the decomposition of water, the oxidation of the metals on the 

 one side, and a chemical change of a contrary kind occurring 

 on the metals at the other side of the portion hitherto less ob- 



