1305 
saturation line a,c, 6,, the liquidum line a dh and the vapour line 
a,d,b, have been drawn only to the extent where they represent 
stable conditions. 
We have noticed previously that from the system F+ L + G, 
which exists at the pressure Pj;, are formed, on increase in pressure, 
the systems F+ G and £-+ G'; we find this confirmed here also 
in figs. 1 and 2. We also notice, in agreement with the rule given 
above that the two three-phase triangles Faa, and #55, turn, on 
reduction in pressure, in such a manner that the conjugation line 
solid-liquid gets in front; on increase of pressure the conjugation 
line solid-gas precedes. 
I must leave the consideration of the other cases to the reader. 
In our previous considerations we have compared the course of 
the saturation- and vapour-saturation lines under their own vapour 
pressure with the change in volume that takes place in the con- 
version of / + L and of (+ G into F+ L’ + G’. In the same 
manner we might compare the course of the boiling point-line and 
the vapour-boiling point line with changes in entropy occurring in these 
reactions. Instead of increasing, or decreasing the volume of the 
systems M+ L and F+ G we must either supply, or withdraw, 
a little heat to, or from the same. 
If we distill a ternary liquid at a constant temperature, then, as 
is well known, the pressure continuously decreases during the distil- 
lation. The liquid and the at each moment distilling vapour proceed 
along a curve which we distinguish as the distillation curve of the 
liquid and of the vapour. We obtain, as is well known, clusters of 
these distillation curves which emanate from one or more definite 
points (the distillation points) and meet in one or more definite points. 
If now at the temperature of distillation a solid substance / also 
occurs, this can modify the course of the distillation lines; of course, 
not the theoretical but the experimental course. 
According to whether the initial and terminal points of the distil- 
lation curves are situated within or without the saturation line of 
F under its own vapour pressure, we may now distinguish several 
eases, of which we will only take a single one. 
Let us choose a temperature below the minimum melting point 
of the solid substance /’, so that its saturation line under its own 
vapour pressure is circumphased. In fig. 38 has been drawn a part 
of this saturation line with the point of maximum pressure J/ and 
of minimum pressure m; the dotted curve M‚,s,4,b, is a part of 
the correlated vapour line. 
