719 
below gt. For this we draw a horizontal line ryz in fig. 3; we 
assume that all the points of this line represent liquids. (Those liquids 
are then partly stable, partly metastable). In the point « this liquid 
is water, while the percentage of salt increases starting from 2 
towards w. Consequently the vapourpressure decreases along this line 
starting from # towards u. 
The horizontal line vyeu is represented in fig. 4 by the vertical 
line wyzw; as the vapourpressure in the point « is practically zero, 
this point has not been drawn in fig. 4; it is situated in the imme- 
diate vicinity of the Z-axis. The point w is situated on the metastable 
part of curve tv, point y on curve (qt) —(S) and point z on curve 
ga=(f). Hence it is apparent that curve ga must be situated, 
therefore, below qf. 
. As the concentration-diagrain of fig. 4 is the same as that of fig. 1, 
the P,7-diagram of fig. 4 must belong also to the same type as 
that of fig. 1. We see that this is the case; both P,7-diagrams 
fig. 1 and 4] consist viz. of a threecurvical and a onecurvical 
bundle; in both diagrams curve (M) is also a middle-curve of the 
(CM )-bundle. 
Just as the P,7-diagram of fig. 1 the reader may deduce also 
that of fig. + in different ways; just as in fig. 1 we are able to 
draw the bivariant regions also in fig. 4. As this figure would be then 
overfilled with letters, I give in (1) a symbolical representation. 
[Compare communication IV], The reader may indicate them in a 
P‚T-diagram, which is drawn on a larger scale. 
Stab. (@ (SCM) (1) (L)(M) (G) 
ere Ee ee Ty A OP 1 n8 
; | | 
Ren LD) @) (8) © 
When in the binary system: water + salt S occurs a hydrate H, 
then the equilibrium : 
lee + GH LH 
may occur in the eryohydratie point q. When this point // is situated 
as in fig. 3, in which gb represents the solutions, which are saturated 
with M under their own vapourpressure, then the P,7-diagram is 
the same as in fig. 4; in this we have only to replace (S) by (H) 
and a by 6. Curve gb in fig. 4 obtains then in its further proceeding 
