708 
of which the first has only been mentioned as yet. The second 
differs from the first only in this that the melting-point diagram 
possesses a eutectic point. 
Fig. 3 represents in this case the 7'r-projeetion ef the three- 
phase regions of the pseudo system with the two phase regions of 
the unary system lying in them. 
This figure, which does not call for any further elucidation, also 
represents a case not considered up to now, for which the solid 
nhase lies between the two others on one three-phase region for 
SH Lt G, the situation on the other three-phase region being the 
usual one. At present there is no reason to prefer one representation 
(Fig. 2) to the other (Fig. 3). 
In conclusion it may still be pointed out that as is known, Hel, 
at high temperatures begins to split up appreciably into Hg,I, and 
I,. This splitting up is disregarded here, because evidently it is not 
essential here for the phenomenon of allotropy. 
SUMMARY. 
On the ground of new researches a modification was applied to 
the representation of the system mercuryiodide, which has entirely 
obviated all the former difficulties and in consequence of which an 
altogether satisfactory concordance with the observed phenomena 
was obtained. 
Anorg. Chem. Lab. of the University. 
Amsterdam, Sept. 1916. 
Chemistry. — “On the Injluence of the Solvent on the Situation 
of the Homogeneous Equilibrium”. 1. By Prof. A. Smits. 
(Communicated by Prof. F. A. H. SCHREINEMAKERS). | 
(Communicated in the meeting of October 28, 1916). 
1. It is universally known that the solvent frequently greatly 
influences the situation of the homogeneous equilibrium. This has 
appeared, for instance in the determination of the equilibria of the 
triazol carbonic acid esters in different solvents, carried out by 
DimrotH *), and from vor HALBAN'’s ®) researches on the conversion 
1) Lieb. Ann. 377, 133 (1910). 
2) Zeitschr. f. phys. Chem. 67, 129 (1909). 
