1322 
represented by a point of the diagram in the first case; the liquid 
in the second case. . 
The line of demarcation of the regions 1 and G represents the 
vapours which can be in equilibrium with solid /, that of the regions 
2 and G those which can be in equilibrium with solid /”’. The line 
of demarcation of the regions 5 and G represents the equilibrium 
L° + G, that of the regions 5 and 6 the complex £ + G of the 
system /’+ + G and that of the regions 5 and 7 this same complex 
of the system /” + LG. 
If in agreement with fig. 1 we take a temperature higher than the 
minimum melting point S of the complex /’-+ #” and lower than 
the maximum sublimation point A’ of the substance /” we obtain 
a diagram as in fig. 4. If in agreement with fig. 1 we take a tem- 
perature higher than the maximum sublimation point AC of the sub- 
stance /’ and lower than the minimum meltingpoint /” of the com- 
Fig. 4. Fig. 5. Fig. 6. 
pound /” we obtain a diagram as in fig. 5. If finally we take a 
temperature higher than the minimum melting point /’ of the com- 
pound #’ we obtain a diagram as in fig. 6. 
Between the diagrams figs. 2—6 exist different transition forms ; 
we must also consider the possibility that, in fig. 1, we can draw 
lines parallel to the P-axis which cut the curves Dk, Dk’, SP 
and SF” in two points. We will not, however, discuss here these 
transition forms. 
When deducing the diagrams it has also been assumed that the 
points D, K’, K, S, F’ and F are situated in regard to each other 
as drawn in fig. 1. But this may be different. 
As a rule, the points S, F’, and F and also the points D, A’ 
and A will lie in regard to each other as assumed in fig. 1. The 
minimum melting point of the complex /’-+ /” is therefore, as a 
