﻿of the Electron Theory of Matter. 615 



move for the same time between collisions, leads to 



1 e 2 n 1 E 1 T ] + *m 2 S 2 T 2 



cr = — — , (4o) 



I m a-i + aa 2 



Y 1 e n 1 S 1 T 1 2 + a7i 2 S 2 T; 



H X 3 m WiS/1 1 ! +■ an s S s T 8 ' 



(47) 



gR ~ ~ Ho^^iSiTi 3 + an 3 S 2 T 2 3 ) - OAST, + *m 2 S 2 ST 2 \ 



R n l v$ l T 1 -\-cin2$2^2 



... (48) 



Here <r is tbe specific electrical conductivity, Y /H X is the 

 Hall coefficient, and SR/R is the change of resistance in a 

 transverse magnetic field H . 



The point of chief interest is that, as a may very well be 

 negative, the sign of the fraction in (37) might easily be 

 determined by the value of the ratio T 2 /Ti. Thus we have a 

 means of accounting for the oscillation of sign of the Hall 

 effect in the non-magnetic metals without having recourse to 

 magnetic perturbations. On the other hand, we should 

 rather expect oscillations in SR/R if this is the explanation 

 of the apparent instability of the Hall effect, unless the 

 T 3 terms are swamped by the ST terms in (38), which, as 

 E. P. Adams * has pointed out, may easily happen. 



1 do not think that formulae (46) to (48) should be taken 

 as more than illustrative. The current evidence indicates 

 that the mean free path is larger than the probable scale 

 of the polarization structure. Moreover, formula (46) 

 would seriously disorganize the law of Wiedemann-Franz- 

 Lorenz. It seems probable that considerations of this kind 

 will enter as corrective terms of the main factors. They 

 may be of especial importance in the calculation of the 

 conductivity for periodic electromotive forces. 



§ 7. a Photoelectric and Related Phenomena. 



We shall now consider the conclusions to which we are 

 led when we apply statistical and thermodynamical principles 

 to photoelectric phenomena. In the preceding paper I 

 considered the state of equilibrium which results when we 

 have a number of different material substances in an in- 

 sulated enclosure, on the assumption that interchange of 

 energy and electric charge between the different bodies and 

 the surrounding space and each other could take place in 



* Phys. Rev. vol. xxiv. p. 428 (1907). 



