170 V^EBER ON THE CONNEXION OF DIAMAGNETISM 



Art. 10 of the Measurements of Resistance in my Electro-dyna- 

 mic Determinations, is 



=:7rrrX. 



This integral value is the sum of the products of the electro- 

 motive force, reduced to an absolute unit in the Art. 10 afore- 

 said, into the element of time during which the force acts with 

 this intensity. The expression of this integral value remains 

 unchanged, if instead of moving the circle through an arc of 90°, 

 the magnetizing force X disappears. If, on the contrary, this 

 magnetizing force increases from X = to X = X (by closing the 

 circuit), the expression of this integral value is 



— TrrrX, 

 where the negative sign intimates that the induced circular cur- 

 rent has such a direction that the poles of an equivalent molecular 

 magnet are directed in an opposite manner to those of a compass- 

 needle under the influence of the force X. 



This determination of the integral value of the electromotive 

 force refers to the unit deduced from the absolute measure of mag- 

 netism, as established in the place above cited, p. 338 and 339; 



it must be multiplied by a/ - to render it true for the pure electro- 

 dynamic unit of electromotive forces given in Art. 26 of the work 

 cited; hence 



j^.rrX. 



\/2 



4 

 This expression^ multiplied by — (where c denotes that constant 



value of the relative velocity at which two electric masses exert 

 no influence whatever upon each other), gives the electromotive 

 force in terms of the absolute unit of measure for all forces, esta- 

 blished generally in mechanics (see Art. 27 of the work cited) ; 

 hence 



.TrrrX. 



c 



This is the value of the electromotive force for the length of the 

 entire circular path, under the assumption that in every unit of 

 length of this path the unit of electric fluid exists. Dividing by 

 the circumference of the circle 27rr, we find the electromotive 

 force exerted upon each unit of electric fluid to be 



