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conjugation line FPL’ is situated at the other side of /a than the point a 
From all_this it follows that, on reduction in pressure, the conjugation 
line solid-liquid turns away from the vapour point, and that on 
increase in pressure it turns towards the same. 
We notice at once that this is in conformity with the change in 
pressure along the saturation line under its own vapour pressure in 
fie. 7 (1) and 11 (1). 
For if we allow the conjugation line solid-liquid to turn away 
from m towards M or along maM or along mbJ/, it always turns 
towards the vapour point while the pressure increases. We now take 
the case when tie saturation line of / under its own vapour pressure 
is situated, in part, adjacent to the point #. We. now distinguish 
two cases depending on whether the substance /’ melts with increase 
or decrease in volume. 
V>v. The substance melts with increase in volume. For these 
points of the saturation line under its own vapour pressure which are 
removed far from the point /’, “+L will be converted into #-+ L’+ G’ 
with increase of volume; for points in the vicinity of /, F+ L 
may pass into /+ // + G’ with decrease in volume, provided 
that. as stated above, much solid matter is deposited in this conversion. 
We have already seen above in what direction the conjugation 
line solid-liquid turns when /’-+ Z is converted with increase in 
volume into #'— L’ + G’; we may now readily deduce that this 
conjugation line will turn in the opposite direction if that conversion 
takes place with decrease in volume. Hence, we find the following: 
we take from the three-phase equilibrium /’+ + G the two-phase 
complex FL; if F+ ZL is converted into F+ L’ + G with 
increase of volume the conjugation line solid-liquid on reduction of 
pressure turns away from the vapour point; at an increased pressure 
it turns towards the vapour point. 
If F4 L is converted into #4 L’ + G’ with decrease in volume 
the conjugation line solid-liquid turns in the opposite direction. 
Let us now consider the saturation line of fig. 12 (I) under its own 
vapour pressure of which a part is adjacent to {he point /’and which, 
as we have seen before, applies to the case when the substance /’ 
expands on melting (V > v). We draw through # two tangents at 
this curve Mm; we will call these points of contact R and Zi’. 
As seen from the figure, the conjugation line solid-liquid now 
moves, on increase in pressure, on the branch RA/K’ towards the 
vapour point; on the branch Am’, however, it moves away from 
the vapour point. In connection with the above, it now follows 
that the conversion of /+ L into F+ L’+ G’ is accompanied 
