1347 
t, ty ts Uy it 
polymer # in «. No doubt we shall be allowed to assume as a rule 
that the molecular volume decreases at the reaction: 
no p 
and that therefore : 
nb, Or Abi). 
In this case the line for the internal equilibrium in the liquid 
and in the solid phase will move to the side of the polymer on 
increase of pressure. 
This has therefore been assumed in the following P,X-figures. 
We should not forget, however, that as Dr. van Laar*) has demon- 
strated for the substance water, the double molecules H,O, seem to 
possess a greater molecular volume than two molecules H,O, so that, 
when we should want to examine this substance, the lines for the 
internal equilibrium in the liquid phase and in the solid phase shift 
just to the side of the single pseudo-component H,O on increase of 
pressure. 
1) Arch. TeyLeR. Serie 2, T. XI, Troisième partie 1908. 
Zeitsch. f. phys. Chem. 31. 
Proceedings Royal Acad. Amsterdam, Vol. XVIII. 
