185 
will possess a critical end-point 
curve pq, which projected on the 
concentration triangle can have a 
shape as indicated in fig. 1 by 
the curve pg, the temperature of 
which rises in the direction indi- 
cated by the arrows. 
If in the same triangle we draw 
the projection of the eutectic vapour 
C and liquid lines, along which the 
7 temperature also rises in the direc- 
tion indicated by the arrows, we 
Fig. 1. 
see that in the case considered here none of the eutectic lines comes 
into contact with the critical end-point curve pq. 
2"¢ Case. In the second place we shall suppose that in two of 
the binary systems critical end- ZB 
points occur, but in such a way 
that in the symbol for the critical 
end-point S + (G=l), the solid 
phase S is the same in the two 
binary systems. Let the component 
C be here tbis solid phase, then 
we get the following simple pro- 
jection on the supposition that the 
system AB does not possess either 
a minimum or a maximum critical 
temperature. 
Let us consider the case that B possesses a much higher critical 
temperature than A, then the temperature of the critical end-point 
p’ will probably be higher than that of p, and hence the temperature 
will continually rise from p to p’. In this case the temperature along 
the q-line may rise from q’ to q, but the reverse is also very well 
possible; the former has been assumed in the figure. If the system 
AB had a minimum critical temperature, the critical end-point lines 
might get a greater distance, and in the case of a maximum critical 
temperature depressions can occur which may even give rise to a 
closed portion, so that a région is formed where no critical end-points 
occur any more. 
3rd case. The phenomena become much more interesting when the 
critical end-point curve comes in contact with a eutectic line. This 
case may be found when in two of the three binary systems critical 
end-points occur, but so that the solid substance S in the symbol 
Fig. 2. 
