OHM ON THE GALVANIC CIRCUIT. 433 



circuits on which the atmosphere exercises some influence, and 

 whose condition varies Avith time, ■without this change origin- 

 ating in a progressive chemical transformation of the circuit, 

 and is thus distinguished from all the others by the magnitude 

 of its current being different at different places, — I have been 

 content, with respect to each of these, always to treat of only 

 the most simple case, as they but rarely occur in nature, and 

 in general appear to be of less interest. I have adopted this 

 plan the more willingly, as I intend to return to this subject at 

 some future time. But with regard to that modification of 

 galvanic circuits which is produced by a chemical change in the 

 circuit, proceeding first from the current, and then again react- 

 ing on it, I have devoted separate attention to it in the Ap- 

 pendix. The course adopted is founded on a vast number of 

 experiments performed on this subject, the communication of 

 which, however, I omit, because they appear to be capable of 

 being far more accurately determined than I was able to do at 

 that time, from failing to attend to several elements in opera- 

 tion; nevertheless, I consider it proper to mention the cir- 

 cumstance in this place, in order that the careful manner 

 with which I advance in the inquiry, and which I consider to 

 be due to truth, may not operate more than is just against its 

 reception. 



I have sought for the source of the chemical changes caused 

 by the current, in the above-described peculiar mode of separa- 

 tion of the electricity of the circuit ; and, I can scarcely doubt, 

 have at least found the main cause. It is immediately evident 

 that each disk belonging to a section of a galvanic circuit, which 

 obeys the electric attractions and repulsions and does not 

 oppose their movement, must in the closed circuit be propelled 

 always towards one side only, as these attractions and repul- 

 sions, in consequence of the continually varying electric force 

 are different at the two sides ; and it is mathematically de- 

 monstrable that the force loith which it is driven to the one side, 

 is in the ratio compounded of the magnitude of the electric cur- 

 rent and of the electric force in the disk. It is true, how- 

 ever, that merely a change of position in space would be imme- 

 diately produced by this. But if this disk be regarded as a com- 

 j)nund body, the constituent parts of which, according to electro- 

 chemical views, are distinguished by a difference in their elec- 

 trical relation to one another, it thence directly follows that this 



