OHM ON THE GALVANIC CIRCUIT. 439 



on uncertain ground, as there is no touchstone for its hypo- 

 theses, and in fact it would be far better to wait a more fit time ; 

 but when it goes to work with the proper authority, it enriches, 

 at least in an indirect manner, the field it occupies with new 

 natural phaenomena, as universal experience shows. I have 

 thought it necessary to premise these general remarks, as they 

 not only serve to throw more light on what follows, but also 

 because they explain the reason why the galvanic phaenomena 

 have not long since been mathematically treated with greater 

 success, although, as we shall subsequently find, the requisite 

 course has been already earlier pursued in another, apparently 

 less prepared, branch of Physics. 



After these reflections we will now proceed to the establish- 

 ment of the fundamental laws themselves. 



3. When two electrical elements, E and E', of equal magni- 

 tude, of like form and similarly placed with respect to each other, 

 but unequally powerful, are situated at the proper distance from 

 each other, they exhibit a mutual tendency to attain electric 

 equihbrium, which is apparent in both constantly and unin- 

 terruptedly approaching nearer to the mean of their electric 

 state, until they have actually attained it. That is to say, 

 both elements reciprocally change their electric state so long 

 as a difference continues to exist between their electroscopic 

 forces ; but this change ceases as soon as they have both at- 

 tained the same electroscopic force. Consequently tliis change 

 of the electric difference of the elements is so dependent that the 

 Dne disappears at the same time with the other. We now sup- 

 pose that the change, effected in an extremely short instant of 

 time in both elements, is proportional to the difference of their 

 cotemporaneous electroscopic force and the magnitude of the 

 Instant of time ; and without yet attending to auy material di- 

 stinctions of the electricity, it is always to be understood 

 :hat the forces designated by + and — are to be treated exactly 

 18 opposite magnitudes. That the change is effected accurately 

 iccording to the difference of the forces, is a mathematical sup- 

 josition, the most natural because it is the most simple; all the 

 best is given by experiment. The motion of electricity is effected 

 n most bodies so rapidly that we are seldom able to determine 

 ts changes at the various places, and on that account we are 

 lot in a condition to discover by observation the law according 

 o which they act. The galvanic phaenomena, in which such 



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