OHM ON THE GALVANIC CIRCUIT. 435 



part preponderating on the one side of any disk, within the 

 portion in the act of decomposition, will, by force of its innate 

 repulsive powei", constantly oppose the movement of a similar 

 constituent to the same side, so that the decomposing force of 

 the circuit has not merely to overcome the constant connexion 

 of the two constituents inter se, but also this reaction of each 

 constituent on itself. It is hence evident that a cessation 

 in the chemical change must occur, if at any time there arises 

 an equilibrium between the two forces. This state, founded 

 on a pecuhar chemical and permanent separation of the con- 

 stituents of the portion of the circuit in the act of decom- 

 position, is the very one from which I started, and whose 

 nature I have endeavoured to determine as accurately as pos- 

 sible in the Appendix. Even the mere description of the mode 

 of origin of this highly remarkable phsenomenon shows that 

 at the extremities of the divided portion no natural equilibrium 

 can occur, on which account the two constituents must be re- 

 tained at these two places by a mechanical force, unless they 

 pass over to the next parts of the circuit, or, m here the other 

 circumstances allow, separate entirely from the circuit. Who 

 would not recognise in this plain statement all the chief circum- 

 stances hitherto observed of the external phsenomenon in che- 

 mical decompositions by the circuit ? 



If the current, and, at the same time, the decomposing force, 

 be suddenly interrupted, the separated constituents gradually 

 return to theu- natural equilibrium ; but tend to re-assume im- 

 mediately the relinquished state, if the current is re-established. 

 During this process, both the conductibility, and the mode of 

 excitation between the elements of the portion in the act of 

 decomposition, obviously vary with their chemical nature ; 

 but this necessarily produces a constant change in the electrical 

 separation, and in the magnitudes of the current in the gal- 

 vanic circuit dependent thereon, which only finds its natural 

 limits in the permanent state of the electrical separation. For 

 the accurate determination of this last stage of the electric 

 current it is requisite to be acquainted with the law which 

 governs the conductibility and force of excitation of the vari- 

 able mixtures, formed of two different liquids. Experiment 

 has hitherto afforded insufficient data for this purpose, I have 

 therefore given the preference to a theoretical supposition, 

 which will supply its place until the true law is discovered. 



