﻿274 Prof. 0. W. Richardson on the Electron 



same temperature and pressure as those outside B, con- 

 densing them at B, and allowing them to flow down the 

 conductor back to A . 



In evaporating from A the work done is NR0, and the 

 heat absorbed is JS T ( W7 i + e (^i'— V i) +H#)- The work during 



NR 



1he adiabatic transformation from to 6'' is z (O' — O), 



1-7 



the heat absorbed nil, and the pressure changes from p^ to 



/0\y/l-y 

 p^ 1 Q f J . The next step consists in expanding to the 



pressure p x f at the constant temperature 6 f c The work done 



here is — NRr 1 ' log^l ^ ) ' , and an equal amount of 



heat is absorbed. In condensing into A' at constant tempe- 

 rature 6 ! and pressure p x ' the work is — NR#' and the heat 

 absorbed — N(^i' + R0') . The flow down the conductor from 

 A' to A is not accompanied by the expenditure of work, but 

 involves an absorption of heat 



= +Ne 



add, 



1Q> 



where cr is the specific heat of electricity. 



Applying the second law of thermodynamics in the form 



dQ 



J 



= 0, we have, for the entire reversible cycle, 

 N« + R0') AT C e a in A 



— ^-^t — + N<?j yd6=0, 



and since 



Keiog i > 1 »=I^logP 1 - Wl -<V/-V 1 ), 

 and 



R<9' Jogjy^Rfl'logP/-^', 

 we have 



+ ^>--Rlo g f_ ^ogJ-0, 

 whence by differentiation with respect to 6 



