1200 
sented by fig. 2, in which ah and cd are the limit-lines and ef 
the turning-line. 
The same is true for an equilibrium ZE = M+ L or M+ G of 
a binary system A-+ 4 | M represents mixed crystals]. 
The region £ exists in fig. 2 of two leaves, viz. ae fb and ce fd. 
On the one leaf the liquid contains more A, on the other leaf more 
B than the vapour. 
Let us assume that in the binary system A + B a compound # 
occurs. The region Z—= F+ L has then no limit-line Z,, but a 
turning-line ZR; this is the melting-line of the compound £. The 
region = /'+ L is, therefore two-leafed, in the one leaf are situ- 
ated the liquids, which contain a surplus of A with respect to F, 
in the other leaf are situated the liquids, which contain a surplus of B. 
The region K=/?+G of the binary equilibrium A + B has 
also no limit-line, but a turning-line ZR; this is the sublimation- 
curve of the compound F. 
We take a ternary system with the three volatile components 
A, B, and C, in which occurs a binary compound # of B and C. 
We now take the equilibrium H=— #'+ L + G, in which conse- 
quently G contains also the 8 components. [Compare also “Equili- 
bria in ternary systems XI”; in fig. 6 of this communication the 
arrow in the vicinity of point # on the curve going through the 
point / has to point in the other direction]. 
This region Z has a limit-line H4—9; consequently this represents 
the equilibrium F+ LG of the binary system B + C and it 
is indicated in fig. 3 by curve acd; it has in 5 a maximum of 
pressure and in c a maximum-teinperature. 
When no equilibrium ZR occurs, then the region £ is one-leafed 
and consequently it must be situated in fig. 3 within curve abed. 
