506 



WEBER ON THE MEASUREMENT 



It is evident on comparison, that the diminution of the magni- 

 tude of the arc, which without the influence of induction from 

 one oscillation to another amounted on an average to xio*-^' ^^^'^ 

 the cooperation of the induction rose to y^th part. 



When for the multiplying coil with the current transmitted 

 through it, a magnet equivalent in an electro-magnetic point of 

 view is substituted, the diminution of the arc is found to be 

 equally great, i. e. the magnetic induction of this magnet is equal 

 to the voltaic induction of the cuiTent in the multiplier. 



The velocity which the inducing motion must possess for the 

 intensity of the induced current to be equal to that of the in- 

 ducing current, may also be deduced from these experiments. 



B. Determination of the duration of Momentary Currents, as 

 also its application to Physiological Experiments. 



When the intensity of a continued constant current is to be 

 determined, both the galvanometer (the sine- or tangent-com- 

 pass) and the dynamometer may be used ; but if the cui-rent, the 

 intensity of which is to be determined, is merely of momentary 

 duration, observation made with either of these instruments is 

 not sufficient, because the deflection observed does not depend 

 merely upon the intensity of the current, but also upon the 

 duration itself. It is therefore requisite, in experimentally in- 

 vestigating the intensity of the current, also to determine its 

 dur-»+ion. 



