506 
If the 68°-acid and the 42°-acid are chemically different, the “seeding” 
power of the former must be a property resident in the molecule. 
It is therefore impossible to explain why a nucleus of 68°-acid or 
a trace of this substance is capable in a short time of converting a 
large quantity of 42°-acid, while, when the molecules of the 68°- 
acid were distributed in a regular manner among those of the 42°- 
acid, as must be the case with mixed erystals, no transformation 
took place until 2.9°/, of 68°-acid was present. 
Fusion experiments have also led these investigators to assume 
the existence of solid solutions or mixed erystals. On p. 213 they 
write: “Hin Teil der eben besprochenen, bei 42° schmelzenden 
Erstarrungsproducte bleibt jahrelang unverändert, ein anderer Teil 
verwandelt sich bei Zimmertemperatur, zuweilen schon nach Minuten 
oder Stunden ohne erkennbare Ursache in 68°-Säure. Diese erstarr- 
ten Schmelzen sind also unter einander nicht gleich; sie sind ebenso 
wie die aus den Lösungsgemischen erhaltenen Verdampfungsriick- 
stände, feste Lösungen oder Mischkristalle mit wechselnden Anteilen 
68°-Säure und +42°-Saure'). It is not altogether improbable that 
these transformations could be brought about by one or more atmos- 
pherie nuclei which had not been broken up, in cases where no 
care had been taken to ensure the removal of these. A single nucleus 
remaining in the melt is sufficient to cause transformations of this kind. 
On the assumption of the trimorphic nature of allocinnamie acid 
it might be expected that, when the different forms were melted, 
the dissociation into single molecules would be more complete 
according as the time of heating is longer and the temperature higher. 
This was confirmed by SroBBr and Scndnsure for the 58°-acid 
(p. 239) and the 68°-acid (p. 211). In these experiments only 5—7 mer. 
was introduced into each capillary. Experiments with 10—50 mer. 
of the 68°-acid in larger capillaries showed that even heating for 
twenty-five minutes at 70° was not sufficient, even in a single case, 
to bring about a permanent change into the 42°-acid, while on 
heating 5—7 mgr. of the acid for ten minutes the transformation 
was effected in four out of ten experiments. The same thing has 
already been stated by other observers, namely, that large quantities 
are more difficultly transformable than small quantities. 
melt, is certainly by no means always correct. Nuclei are molecule-complexes, and 
the molecules of the nuclei in different parts of the melt with nuclei are not 
necessarily uniformly distributed. On the other hand it-is precisely in the case of 
a solid solution or of mixed crystals that we have a uniform distribution of the 
molecules among themselves. 
