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crystals are formed they must have the composition given by the 
point on the line ZB, which lies on the horizontal line drawn 
through the point on CB which corresponds to 20 pCt. of J-oxime. 
The solid mass, weighing 0.69 gram, which was deposited from 
7 grams of liquid, containing 21.7 pCt. of /-oxime, was found to 
contain 32 pCt. The composition of the solid was determined by 
polarisation and corrected for the adhering mother liquor. The 
quantity of the latter was determined by adding some CH Br, and 
determining the bromine in the liquid and in the drained crystals. The 
result agrees very well with the position of the line DB determined 
from the final solidification points. 
Not only do we obtain thus a continuous series of mixed crystals 
on solidification, but we have here the first example of such a series 
with a maximum meltinepoint, which naturally lies at 50 pCt. 
In agreement with the theory the composition of the fused mass 
and of the mixed crystals is the same at this point and the interval 
of solidification therefore vanishes. 
The opinion, which I expressed, that even in the case of mixed 
crystals of optical isomers the equality of melting points, looked for 
by Kuppinc and Pops, does not necessarily exist, is confirmed by 
this example. 
It is worthy of attention that the rule, that racemic compounds 
with a higher density than their active components also have a 
higher meltingpoint, appears to be applicable also to mixed crystals; , 
always providing that the difference in density observed at the 
ordinary temperature still exists near the melting points. Probably 
this will remain, at least qualitatively, unchanged. 
The possibility still exists that carvoxime forms mixed crystals 
on solidification, which change at lower temperatures wholly or 
partially into a racemic compound. 
Between 10° and 90° however no indication of such a change 
could be found by means of the dilatometer with an inactive mixture. 
That at lower temperatures the inactive oxime, obtained from 
solutions for example, is a mixed crystal and not a compound is 
supported by the great crystallographic similarity between the in- 
active and active crystals which BEYER has observed (Zeits. Krystall. 
18, 296, 1890). 
The density rule of Rererrs would, therefore, not hold good for 
this kind of mixed crystals. 
