Wave-trains through Layers of Electrolyte. 



543 



an equation which would give the form of the curve if no 

 interference took place. It is not a simple logarithmic curve, 

 inasmuch as we have to take account of multiple reflexions 

 inside the absorbent layer. If we again put the conductivity 

 = 0, the centre line becomes a straight line parallel to the 

 base instead of a drooping curve. 



If we put in (7) Z=go, Q vanishes ; i.e. as the length of 

 the layer is increased the humps on the curve disappear. As 

 I have already mentioned, this is due to the fact that the 

 wave-train is a rapidly damped one so that interference is 

 not perfect. 



I have calculated a curve for the first zinc-sulphate solution 

 by these equations ; the theoretical and experimental curves 



The dielectric constant of the 



are shown together in fig. 6 



Fiff. 6. 



Centimetres ...20 40 60 80 100 



Comparison of experimental and theoretical curves 



for the first zinc-sulphate solution. 



Data for Theoretical Curve. 



Wave-length X= 106 cms. 



By Kohlrausch bridge cr=5100 ohm. cms. 



Assumed log. dec y=04. 



solution is known from the experimental curve ; this gives us 

 b, v 2 , and t 2 . The primary damping 7 we do not know, but an 



120 



