426 Prof. Rowland on the Propagation of 



way we readily find the effect of a general electric or magnetic 

 disturbance. 



Let the components of the arbitrary electric displacement be 



XV*w X'V*™ 



Y f e mt , and of the magnetic induction Y"e mt , 



Z'e im , Z"e mt ; 



where, in general, we must replace X', Y', Z', and X", Y", Z", 

 by a quantity of the complex form, and add another quantity 

 with — i in place of +i. Putting D + iE for X x , and adding 

 the other term, we should have the real form 



(D + iE)6^ + (D-iB)6- OT '=2{DcosSV*-EsinJV^, 



which expresses the disturbance in any phase. But this is 

 only necessary when we descend to actual calculation. The 

 effect of this general disturbance is then found to be : — 

 The electric displacement, 



F= g^— 3 { X' (2C + G 2 y -3S'(V 



G / = 



87rC /3 : 



jJY^Co+C^-SS'C^ 



H'= ^jp{ Z'(2C + C 2 y-3S>C 2 z 



BK J^ p [Y"a!-X /, if] Xe-W-^dv. 



The magnetic induction, 



^{x"(2C + C 2 V 2 -3S"C 2 tf 



+ l^Pr 



[X'«-ZV|} 



KV 



H"= g^{ Z"(2C + C 2 )p 2 -3S"C 2 z 



