﻿-±80 Prof. D. X. Mallik on the 



On eliminating /and patting \m — fic = Q these yield 



/ + A = v 2 / and Ci. // +/ r, =o 1 f A+a 1 f A. 



And if / varies as cos pt, these equations are or the same 

 form as (38). 



34. Inasmuch, however, as 



dA BB dC 

 and Sr' 3? B/i _ 



(A, B, C) and (f, g, h) cannot be interpreted as rotations, 

 each by itself, and to that extent these theories are less 

 general than the electron theory. 



The main difference, however, consists really in the fact 

 that the elastic solid theories deal with sether and matter, 

 while the electron theory deals with ?ether and electron. 



35. In attempting a comparison between the elastic solid 

 theory and the electron theory, we have identified the elec- 

 trostatic energy with the energy o£ (rotational) strain of the 

 elastic medium, and the electromagnetic energy with its 

 kinetic energy. 



36. But the identification is not unique, as we do not know 

 which of the two expressions (in either system") is kinetic or 

 which potential, or in fact whether both the energies are not 

 (as they most likely are) kinetic. We may, therefore, if 

 we like *, regard electric force as identical with the rate of 

 elastic displacement and magnetic force with molecular 

 rotation. 



37. On this scheme, the electromagnetic energy 



If^(«2 + £2 +7 2y T 



87T 



< 



is to be identified with the energv of strain 



J 



provided we have 



(*4«)a=o, 



* Glazebrook's Address as President of the Plivsical Section, B. A. 

 1893. 



