( 265 ) 
point £(116 a 117°) at 50% of amimnia and the maximum sublima¬ 
tion point M (88.4°). The liquid curve was partly determined by the 
method of closed tubes, partly by the Cailletet method, which yielded 
concordant results; the dotted part, which could not be accurately 
observed partly on account of the mentioned disturbing reaction, partly 
Fig. 8. 
because the quantities of substance in the Cailletet tubes would have to 
be too small, agrees only roughly with the actual state of things 
with the exception of the maximum sublimation point. On the left 
of N the melting-point lies at higher temperature than the sublima¬ 
tion point, and on the other side of N the reversed situation occurs. 
The point N, where the two branches of the two-phase region 
intersect, is also to be found in the P-7 1 -projection of fig. 6, where 
the minimum line of the liquid-vapour surface touches the three-phase 
line. With the aid of the theoretical description which Prof. Smits 
gave of this case (Type I), the other lines will be clear without 
further explanation. 
