394 
SHL, + G (linec); the equilibrium L, + L, + G is still metastable. 
This condition continues to exist till the line for the fluid phases 
coexisting with solid gets into contact with the liquid branch of the 
transverse plait in A, and then also passes through the righthand 
cusp in the vapour branch of the transverse plait (line d). This is 
followed by a range of temperature, in which six points of inter- 
section with the transverse plait, and still two with the longitudinal 
one occur. At these temperatures five three-phase equilibria then 
appear in all. This range terminates at the temperature of the curve 
f, where again contact with the liquid branch of the transverse 
plait is found (in B), and the line for fluid by the side of solid 
passes through the lefthand cusp of the vapour binodal curve. In 
this temperature range we find the quadruple point, the behaviour 
of which is given by the curve e. Above this range of temperature 
four points of intersection again occur, till the temperature is raised 
to that of g, where contact with the longitudinal plait takes place. 
Then eight points of intersection again follow, six of which, however, 
now lie on the longitudinal plait. This continues to be so till the 
condition / is reached, above which again two intersections with 
the longitudinal, and again two with the transverse plait take place 
(curve 7). At last in / the temperature is reached at which contact 
in the hidden plaitpoint P, takes place. At still higher temperature 
Fig. 2. 
there is no longer contact of the fluid line with the longitudinal 
plait, and the latter will recede within the transverse plait. 
After this discussion it will be easy to construct the P, 7-projection 
of the three-phase lines, which has been given in fig. 2. The tem- 
