

Intell 



\igence and Miscellaneous Articles. 315 



II. There exists 



no electrical polarization ; then is 







^' - ,CX' 







A 



id we have 





E=0, 



W=A=T = — U^. 



cr 



If A then 



arises 



from electric currents, it follows that, while the 



whole of the light is transmitted by insulators, it is entirely ab- 

 sorbed by perfect conductors, and the total store of energy is con- 

 verted into electric currents. 



In the general case, if the energy of the light (that is, [that of 

 the electric vibrations) be denoted by L, and that of the electric 

 current bv S, we have 



W=L + S, 

 where 



S=A=:^'|;U^. 



Since the factor ■U'2_g_2;?^_.^_4;r/xcva: occurs in the expressions 

 for both energies, both energies continually diminish. 



If h^ denotes the loss of energy correspondiug to L (diminution 

 of polarization), and ^^ that corresponding to !S (which proceeds 

 from the current), the total loss of energy is 



Putting, for the sake of abbreviation, 1— 1]" =■'[]'" =2px — 2p^x^ ... , 

 we get : — 



a..= ^Cij-. 



Hence both with conductors (with which p= A:, ^^ = 0) and noncon- 

 ductors (with which p = 0) we have 



For small values of x, c^ and ^2 are nearly proportional to cc. 

 The losses of electrical energy corresponding to r, and ^2 ^'^^ Pro- 

 bably the consequence of heat-development, which, accordingly, 

 must always, with the exception of perfect insulators, accompany 

 electrical polarization. 



