316 Mr. G. U. Yule on the Passage of Oscillator 



Thus for the transmitted ray at the dielectric-electrolyte 

 surface, the change of phase is ^ — yfr f , and the ratio of its 

 amplitude to that of the incident ray or c is 



\ / 1 + r 2 + 2r cos -x 



c, like b, is a function of the period and damping of the in- 

 cident ray ; like b it remains a function of the period even 

 for an undamped ray ; and like b it becomes a function of 

 the dielectric constants only, if the " electrolyte " be a perfect 

 insulator, the expression in (17) becoming 



'"'8 



ft 



(17a) 



ft 



We have now sufficient data to determine the speed of 

 propagation and wave-length in the electrolyte, before going 

 on to deal with the reflexions and refractions at the second 

 surface. Referring back to equation (4) for X 2 , and substi- 

 tuting the values we have determined for B 2 , p, and </, we 

 have 



X 2 = cA 1 e i ^ 2 ~^' ) e ( ~P^ +i P^ t e yiV ^{ C09(x+el2) ~ i sin (x +0 / 2 >l* 



or retaining only the real terms 



X 2 =cA ie - p ^ ^"".(* + -T> cos {pt-vSfr S in( % + f). 



+ |_f }• • • . (18) 



Hence the speed of the wave in the electrolyte is 

 Pc sin y 



v 2 = — zzt^t W\=-^ — / — e\> • ( l9 ) 



V Vft*P sin [x+2j ^ 2/? Sin \ X + 2/ 

 and the wave-length 



X 2 = —, F . • • • (20) 



V V&psinUj-f-g) 



