410 



Sir 



J. J. Thomson on 



the Scattering of 



Let 





d¥ 



dz 



-S-* 





when z = 



■ d, th 



en 



2e.8z 



Zd 



" /3F ; 





and from the 



equilibrium of the 



system, we have 







2e 2 ¥ 



" 4tf 2 * 





Hence 





2e8z : 



8d 3 Z 





Hence c — Sd z //3 and a = b = 8d 3 . 



The ratio of the minimum to the maximum intensity of 

 the scattered light is therefore, by equation (2), equal to 



2Q3-1) 2 

 9/3 2 + 2/3 + 4' 



Another system of which the hydrogen molecule may he 

 taken as a type is that of two positive charges A and B : 

 and two electrons G and D, arranged as in fig. 3. 



If the plane of the system be taken as the plane of a, ?/, 

 then, if £>z is the displacement of an electron due to a 

 force Z at right angles to the plane of xy, we have, by- 

 taking moments about AB, 



.8s = ZHCD, 



<TD* " 2 



or 2e. hz = Z . CD 3 ; 



thus c is proportional to CD 3 . 



If the system is acted on by a force X parallel to AB, 

 and if e 2 F is the force between a positive charge and 

 an electron, 



where r is the distance between the positive charge and an 

 electron, from this we get, if we put -y- =- F, where F and 



r have the values corresponding to the undisturbed position, 

 2e.-(l- (1-/3) cos 2 6) hx = X, 



or 2eS. 



F(l-(l-£)cos 2 0) 



