(558 ) 
attained. In the upper direction a terminating point would only be 
conceivable in the case of the occurrence of a solid phase. If an 
increase of pressure promotes the separation of the two layers, DM 
would then run from the point J/ to the right instead of to the left. 
In the case, therefore, in which the two liquid layers possess an 
upper mixing point J/ which lies below A,4,, the critical lines 
AOM, for GL and DM for LL, are quite independent of each other. 
If, however, the upper mixing point is not yet reached below 
KK, CM will continue up to a meeting point with A,A,. As the 
phases occur in the order GL,L,, G will then become identical 
with “, in O, Fig 4. 
The critical line A,O is here at the same time broken off. From 
a consideration of a series of p, v-diagrams for successive temperatures 
we may, according to Mr. BücHrer, easily demonstrate graphically 
that the other end of the eritieal line GL, which commences in K, 
now amalgamates with the upper part of the critical line LL, the 
lower continuation of which is not realisable owing to the absence 
of J/. In this way is formed the critical line A,PD whose upper 
part may eventually also run to the right. 
A junction of the three-phase line GL,L, with the critical line 
GL in O will, secondly, always take place when ZL, and L, diverge 
by an elevation of temperature. This may frequently oceur with two 
liquid layers which have a lower mixing point J. The three-phase 
line GL,L, then terminates in O by intersection with the critical 
line GL and in Jf by intersection with the critical line IP for 
L,=L,. From the p, r-diagrams we may now again deduce that 
the upper continuation of this line is not now realisable because the 
lower part coincides with the second part of the critical line GL 
which proceeds from A. In this way the critical line 12’ PK, originates. 
Lately, KuerNeN has 
found instances of the 
cases represented by 
Figs. 4 and 5. 
The figures 1, 4 and 
5 exhibit the three 
main types of the 
manner in which the 
three-phase line meets 
either the critical line 
GL or the critical line 
L, L, and then finds 
1 or 2 terminating 
