PEIRCE. — CHANGES IN INDUCTANCES OF ELLJTRIC CIRCUITS. 547 



and 



10' 



(14) 



The curve ONJ of Figure 6, which has been carefully drawn to scale, 

 represents the growth of the current with the time in a circuit without 



Figure 5. If I centimeters parallel to the horizontal axis represent one 

 second, and an ordinate m centimeters long one ampere, A . 10^ . r/lm (where 

 A is the area, in square centimeters, of CDGF) represents the change in the 

 magnetic flux through the circuit during the interval KL. 



iron, of resistance r and inductance L. The curve OPT represents the 

 current in the same circuit when the inductance has been increased to 

 AL, while the resistance is the same as before. If, when the induc- 

 tance of the circuit is L, the current rises in the time OU to the value 

 UN, and if then the inductance is instantly increased to 4Z, the cur- 

 rent falls to UF and then rises again in the manner indicated by the 

 curve FG, which is the curve OPT moved to the right through a dis- 

 tance OL just great enough to make its ordinate at the time OU equal 

 to one fourth of UN. Since the area between the curve and its asymp- 

 tote is proportional to the inductance flux through the circuit, it is 

 clear without any of the reasoning of the preceding paragraphs, that 



