Electron Theory of Matter. 185 
These give 
, t, S 2 2P 
■ /W + R-Tp + — 
P L p 
77= —^Beli cos 6 ^ op . , * rvr — T " 
The component of the resulting increase in moment in the 
direction o£ h is Bnh cos 6 = ^nej3cos Ol— — t] \ by (17). 
Substituting the value of * —y, and averaging for all rings 
of an element of the substance, we find for the mean effective 
moment per ring due to axial magnetic force 
ne 2p2 m ft )-+R- T +y 
*" 1 *"*i«Ai 2 / p s 2 2P\/- # . — ^7^"^^u* (20) 
,na " + ( R — f + yjlm + s^l 2 *-pWi 
§ 19. We shall now use our equations to determine the 
part of the moment due to the radial magnetic force, which 
produces the axial mechanical force 
-Pehsm0cos(e>t + 8+~^\ (§ S (6)). 
The increase in the moment is given in § 9 (c) (9), and is 
equal to 
Sm 2 =inej3{-C, -C, 0), 
w 
here S=Ccm(mt + $ + —?) + C sin (a>* + 8 + ^V 
Thus we need calculate only the axial displacement £. 
In the present case we have k= —1, q=(o, so that as before 
q + kco = 0. We find by § 15 
H=jcot^, M=H-K, N = 2K-H. . (21) 
It follows from equations (15), by using the continuation 
formulae for Bessel Functions, that in the present case 
C-C„=^-J„-/3g+3V ) i?-A=V 
