a 
No 
nn 
and further the equilibria: 
(le) = G 4 LH H [Curve (J or qa fig. 6 and ga fig. 5 | 
(G) Ice + L-+ A [Curve (G) fig. 6] 
Besides the curves (M), (L), (H), (4) and G we find in fig. 6 
also the triplepoint ¢ of the water, és: the melting-curve of the ice 
and ¢v the evaporationcurve of the water. 
It appears from a comparison of the figs. 4 and 6 that curve 
(S) = qt from fig. 4 is replaced in fig. 6 by curve (H) = qt. Curve 
(1) = qa, which represents the equilibrium G +4 1+ H, proceeds 
in fig. 4 from g towards higher 7’ and P; in fig. 6 this curve 
proceeds, however, starting from gq towards lower 7 and P. The 
metastable part gm of this curve has its point of maximum tempe- 
rature in the vicinity of the point m [figs. 5 and 6]. 
When we draw in fig. 5 the horizontal line eyzw and in fig. 6 
the vertical line vyer corresponding with this then we see that the 
different curves must be situated with respect to one another, as is 
drawn in fig. 6. 
As the concentrationdiagram of fig. 6 is the same as that of fig. 1, 
the P,7-diagram of fig. 6 must therefore, belong to the same type 
as that of tig. 1. We see that this is really the case. 
Now we take the binary system: water + salt S, of which S 
occurs in two modifications S, and Sz. In fig. 7 q is the solution, 
saturated with the two modifications under its own vapourpressure. 
Consequently we have the equilibrium : 
GG: 
Curve (q3) [fig. 7] represents the solutions of the equilibrium 
G+ £-+ Sz; it terminates in the meltingpoint 3 of the modification 
Sz. Curve dq represents the solutions of the equilibrium GH LS; 
the metastable prolongation ga of this curve terminates in the meta- 
stable meltingpoint « of the modification S.. 
Curve qo represents the solutions of the equilibrium SSH; 
with this we have assumed that this curve proceeds starting from 
gq towards higher temperatures. 
We have the singular equilibria : 
(M) =S, + Sz [Curve (M) fig. 8] 
(LD) =S, Sz U [Curve (Z) fig. 8] 
(G) =S, + Sen L [Curve (G) or go fig. 8 and go fig. 7] 
and further the equilibria: 
46 
Proceedings Royal Acad Amsterdam. Vol. XIX. 
