172 



Electric Current and Induction. [Feb. 12, 



two others, we obtain 4ot/mu = — V 2 L— — (— + + ^\ and two ' 



dx\dx dy dz ) 



others, which can be solved in the same manner as Maxwell's equa- 

 tions, from which they only differ in form, in signs. The quantity 



<7L , dM. . cZN . , i , - . , , 



— + — -f- — — is, however, not zero, and on lormmg the equations 



dx dy dz 



for electric intensity, it is found to give rise to a triple integral having 

 value at surfaces of contact of dissimilar substances and at charged 

 surfaces. 



In the case when there is no material motion the components of 

 electric intensity are — 



and two other equations. 



If the system is steady, ~ = 0. 

 On putting 



dx dy dz J J J r 



Ave obtain P = — and two other equations. 



dx 



It is shown that these equations may be obtained without the 

 special hypothesis as to the mode of motion of the magnetic induc- 

 tion, by assuming L=/Tcft, M=/Qcft, N"=/R<fr. 



Equations are also obtained by considering the growth of the 

 electric induction. 



