( 276 ) 



For abnormal substances this quantity would probably be found 

 of the same value, but this would require a closer investigation, 

 into which I shall not enter here. For this reason I ha^•e made a 

 reservation for abnormal substances above. 



For the value of ( ;t^ I of the plaitpoint curve we get now the 



equation : 



2M>^ -tT-^^ d^___^^xdv^___ 



Kit),.,- i^öTA."*'öfVö>Y 1 ö> • • ^^ 



^ö.i'öry MRT d.i-du' 

 The critical point of the component is an homogeneous phase, in 

 the same waj the plaitpoint is a new homogeneous phase. But the 

 quantities Ty.,Vy. and ,i' =: increase bv dTy,(h\ and (b\. Hence: 



dp = ( ^ I dTy + I -^ I dx, + ( / ) div 

 and ( ^ ) being 0, also 



\OvJxT 



dTj,,, \dTj,..c K^'vJvT dT 



comparing with (4) we tind the value sought of 



d> 1 fbp 



dT öa'öy ' MRT \dxJvT 



