( 282 ) 

 and so for .i\ and x.^ infinitely small : 



^1 J \OxJvT 



/dp\ 

 If we represent the mean value of :r- between the values 

 V^Vrr 



V, and i\ l)v I ^] , we may also write : 



This mean value can also be represented under another form 

 bv the followino; consideration. According? to Maxwell's rule 



Pc{i\-v 



'2 



when pc denotes the tension of the saturated vapour of the component, 



from which follows : 



?•» 

 dpc, , , d{v,~v^) r'f^p\ , , d{v,—v,) 



dx ' dx J \oxJoT dx 



or 



The quantitv -^ represents the molecular increase of the tension 



O.i' 



of the saturated vapour for the unsplit mixture, assuming for pc the 

 approximate value 



ipc — ip. —f—Y 



r-^ is found from : 

 ox 



