1336 
d$>—=—ydT + vdp + (u, M, —u, M)de .. . (1) 
in which u, M, and u, M, represent the molecular potentials of the 
two components. 
If we assume now that the two components can be transformed 
into each other, and that therefore an internal equilibrium can set 
in, then in this state 
TN OA aS ee Aka (2) 
02) rp 
In connection with the well known shape of the §,x-line this 
from which follows that: 
result means that the internal equilibrium is situated in the minimum 
of the ¢,x-curve under consideration. 
When we consider that the psendo-components are certainly 
miscible to a certain extent also in the solid state, the unary solidi- 
fication point temperature will be a temperature in which a unary 
liquid coexists with a mixed erystal phase, and as the unary liquid 
lies in the minimum of the Z,x-line of the liquid mixtures, the 
coexisting phases mentioned will have to lie at the solidification 
equilibrium on a horizontal bitangent, i.e. also the ¢,x-line for the 
solid mixtures will have to possess a minimum, so also a point 
where: 
0g 
— a) 
da) 7p 
or in other words in the coexisting solid phase internal equilibrium 
will likewise prevail. 
We arrive at the same conclusion also by the following way : 
for the internal equilibrium in the liquid phase holds: 
(Ee (i Wie a oo à oe de (G4) 
for the heterogeneous equilibrium between the liquid and the solid 
substance holds: 
(UR) 5 SCANS oo sla a 3 ©) 
and 
(AEM (Da Ve NGe Se a 6 (G) 
so that 
(ale (RE Te oes Se ee et) 
follows from the combination of (4) with (5) and (6), or in words: 
the solid phase which coexists with the liquid which is in internal 
equilibrium, is itself also in internal equilibrinm. 
It has further been pointed out that in case of the appearance 
