470 Mr. S. S. Richardson on Magnetic Rotary 



Hence 



o o <0 _|_ CO - 



n_ — ni. — ± — — 



0) + ., co_ 



x ~f l 3 



CO + — Q)_ 



2 



(-0 



Now 



£ 2 

 + , 2 2N evH. 



/ 2 2\ ^^ 



Therefore 



co + — ft)_ = — 





2fvRr 



C 



gr 1 -i 



3 Lm^V-O 24 """]' 



on account of the relatively small vnlue of (evH/C) 2 . 

 Thus 



- +~ v 3 ; * c -^v^ 2 -^) 2 



and 



. _v_ Ai 2 -f2 \ 2 2vH v e z 



H ~ 4wCA 3 / * G m^V-^ 2 



v 2 H / n 2 + 2 \ 2 y 

 " 2nC 2 \ 3 / 



**)■ 



?n 1 2 (v 1 2 — v 2 ) 2 



v*H/ w 2 + 2 \%f g 2 | 2 1 



2nC 2 V 3 J \wi(Fi* — f*) J e' 



But from Lorentz's expression for the component of the 

 refraction *, we may put for the effect of each electron 



V-l 1 £ 2 



7i 1 2 + 2"~3?n 1 (v 1 2 -v 2 ) , 



* < Theory of Electrons/ Note 58, p. 308. 



