Page:Outlines of Physical Chemistry - 1899.djvu/118

 ��OUTLINES OF PHYSICAL CHEMISTBY

��But we shall not further dwell on these considerations, especially as the problem would appear to be solved in quite another sense. Hermann Traube ('Jahrbuch fur Mineralogie,' Beilageband, 1896) has found that patchouli camphor, as well as ordinary camphor, has the same rotation in the crystalline form and in solution. 1 This mineralogist believes that the same would be found to be the case for many other active substances, if crystals of

���Two molecules of the same optical ac- tivity.

���The inactive combination.

them large and clear enough could be obtained to allow of polarimetric observations being made on a sufficiently thick section. If this could be confirmed, then Bammels- berg's classification could no longer hold ; at least categories b and c would then form only one class, and the theoretical interpretation of the facts would be very much simplified. It would then suffice to distinguish between rotatory power due to asymmetry in the molecule and permanent through

��1 J, Chem. Soc. 70, ii. 509,

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