NOTES AND ADDITIONS. 



305 



the curve is drawn dovv-nward from the time-line o . . . o . . . f, 

 to indicate that the direction of this induced current i.s 

 opposed to the direction of the primary current. If the 

 primary current is interrupted, it suddenly falls from the 



strength /, as indicated by the straight line 1. With this 

 fall corresponds an inductive current, which suddenly rises 

 very abruptly and again falls somewhat less abruj^tly, as 

 shown in curve 2. From this it is evident that the latter 

 must be physiologically much more effective than the former. 



