1. Let MS now consider two linear condnetors (circuits), in which 

 currents ?', and 4 run. Let M^ be the induction flux passing through 

 the first, M^ that through the second wire. If M^ and A/j change 

 infinitely little, then follows from (1) 



dT =:- (i^clM^ + i, dM^), 

 c 



for which we may put : 



1 1 1 



dT = -d (i, 31, -f J, M,) M, di, J/, di,. 



c c c 



The first member of tiiis equation is a total difterential, as T is 

 perfectly determined by /, and i.„ hence 

 J/, di, + 31, di, 

 must also be a total differential, from which follows: 



di¥, d3L 



V = ^') (-) 



0», Olj 



i.e. the increase of the induction flux passing through the first 

 circuit, caused by an infinitely small current variation in the second, 

 is equal to the increase of induction fiux passing through the second 

 circuit, caused by an equal ciiange of current in the first. 



An increase of the induction fiux dM will give rise to an electrical 

 impulse, in which through every section of the circuit the quantity 

 of electricity 



_ 1 dM 

 c w 



passes, if w represents the resistance of the circuit. The negati\e 

 sign means that the direction of the current, is in lefthand cyclical 

 order with the increase of the induction fiux. 



If now the current z, increases by the infinitely small amount of 

 (//,, tlie induction fiux through the second circuit will increase by: 



I, 



Hence for a short time an induction current will pass through tiie 

 second conductor. If aftev the lapse of this time the current in this 

 conductor has again the same value as before, then the "integral 

 current", i.e. the total cpiantity of electricity set in motion by the 

 induction current amounts to: 



1) For so far as 1 liave been able to ascertain, lliis relation, as well as lliose 

 following later (3), (8), (15) and (17) is new. 



