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a common point of intersection of three curves viz. of the (M)-curve, 
of the sublimation-curve of Hz and of that of Hs. It appears from 
the position of the vapourcurves d/a’c’ and «v’p’2’ with respect to 
tbe line «@ in fig. 9, that the points in which the sublimation-curves 
come in contact with the curves dec and xz in fig. 10, are 
situated at the left of ¢,. 
As long as the vapour, which is in equilibrium with the liquid 
q, is represented in fig. 9 by a point g, at the left of the line u?, 
the P,7-diagram keeps a form as in fig. 10. The P,7 diagram 
changes, however, when the vapour is represented by a point g, at 
the right of the line «2. The singular equilibrium (1/) = H, + H; 
is then viz. no more transformable into the invariant equilibrium 
q, = H+ Ha + G,+ L,,. Curve (M) is then bidirectionable not 
only in point q but also in g, (fig. 10); consequently it proceeds 
now also in stable condition below the point g,. Curve (G),—=H,+ 
+ Hz L continues to be represented in fig. 10 by g,0,; curve 
(LZ), no more goes now, however, starting from g, upwards, but 
downwards. 
The vapours of the equilibria (L) = H.+ Hs + G and (L), = 
=H, + H;+G are represented in fig. 9 by curve gr.g,, which 
has in r, a minimum-temperature. In fig. 10 this point 7, is situated 
somewhere on the (J/)-curve below the point g,. This point 7, is the 
stable terminatingpoint of the curves (£) and (L),. [Now curve (1), 
viz. as has already been said above ascends no more starting from q, but 
it descends]. Point 7, is also now again the common point of inter- 
section of three curves, viz. of the (M)-eurve, the sublimationcurve 
of H, and that of Hs The point in which the sublimationcurve of 
Hf, comes in contact with curve dec, is situated at the left of g,; 
the point in which the sublimation-curve of /7; touches curve v2, 
is situated, however, at the right of g,. 
Now the reader may easily draw the changes in the figures 9 
and 10, when the vapours, which are in equilibrium with the 
liquids, contain more of the substance S than the liquids, 
(To be continued.) 
Leiden, Inorganic Chem. Lab. 
