OHM ON THE GALVANIC CIRCUIT. 453 



body A, x' that of the body B^ and (~r-) ( -^ — ) the particular 



values of t— , -^— immediately belonging to them at the com- 

 mon surface, and in which it was assumed that the origin 

 of the abscissae was not taken on this common surface. The 

 necessity of this last equation may easily be conceived ; for 

 were it otherwise, the two currents would not be of equal 

 energy in the common surface, but there would be more con- 

 veyed from [the one body to this surface than would be abs- 

 tracted from it by the other; and if this difference were a 

 finite portion of the entire current, the electroscopic force would 

 increase at that very place, and indeed, considering the sur- 

 prising fertility of the electric current, would arrive in the 

 shortest time to an exceedingly high degree, as observation has 

 long since demonstrated. Nor can a smaller quantity of elec- 

 tricity be imparted from the one body to the common surface 

 than it is deprived of by the other, as this circumstance would 

 be evinced by an infinitely high degi'ee of negative electricity. 



It is not absolutely requisite for the validity of the preceding 

 determinations, that the two bodies in contact have the same 

 base. The section in the one prismatic body may be different 

 in size and form to that in the other, if this does not render 

 the electroscopic force sensibly different at the various points of 

 the same section, which, considering the great energy with which 

 the electricity tends to equilibrium, will not be the case when 

 the bodies are good conductors, whose length far surpasses 

 their other dimensions. In this case everything remains as 

 before, only that the section of the body B must everywhere be 

 distinguished from that of A ; consequently the second condi- 

 tional equation for the place where the two bodies are in contact 

 changes into the following : — 



(^.)=""'(S'). 



vhere « still represents the section of A, but oo' that of the 

 body B, which at present differs from the former. 



There may even exist in the prolongation of the body A two 

 prismatic bodies, B and C, separated from each other, which 

 are both situated immediately on the one surface of A. If in 

 this case x' co' u' signifies for the body B, and x" w", u" for the body 



VOL. II, PART VIII. 2 II 



