and Electromagnetic Theory, 337 



and case (ii.) to 



«' = °> 0'= H *( W -^) 



The special feature is the appearance of ft' in the first and 

 Y' in the second, in consequence of which a wave with the 

 polarization of (i.) gives rise to a component with the polari- 

 zation of (ii.), of which the amplitude varies as u. The 

 continuity of a'X'Y'/3' (in order) in the combined scheme is 

 expressed by 



H,(l-U/V)+H 1 '(l-U7V)=Hr(l-U"// t V), 



K/i-u/VHwa-U'/v) = ^Mi-U'V/iV), 



f 1 



Ri {>* - y J -Hi \n + v ) - -^- - 



ni'iiH.*' 



K43) 



For transit of energy form the product V(/3'X' — a'Y'), and 

 the result is 



(Vn-^a-U/VJtH^ + H^-CVn'+wJCl-UVVJfH^ + H/ 8 ) 



all products disappearing in virtue of the geometrical equations 

 of reflexion. 



With the object of getting at the ratios HX : HV : H"\" 

 and at the value of A 2 , X is introduced as before with 



X : V : \" = m : mf : m"=V-U : V-U' :- - 51' ; 

 also we write 



X 



=(v.--,/,v- D ,, »" = (^-'-|)/(J-£). 



M«m/(1-U/V), with N' = N and M' = M, and 7c for 1- \ 

 Phil. Mag. S. 6. Vol. 9. No. 51. March 1905. Z 



