Louis Pasteur : his life and labours / by his son-in-law [René Vallery-Radot] ; translated from the French by Lady Claud Hamilton.

  • Vallery-Radot, René.
Date:
1885
Catalogue details

Licence: Public Domain Mark

Credit: Louis Pasteur : his life and labours / by his son-in-law [René Vallery-Radot] ; translated from the French by Lady Claud Hamilton. Source: Wellcome Collection.

Provider: This material has been provided by University of Bristol Library. The original may be consulted at University of Bristol Library.

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    previously extracted from the two tartrates, acids which, in regard to polarised light, behaved like themselves. Such was the worthy opening of M. Pasteur's scientific career, which has been dwelt upon so frequently and emphatically by M. Eadot. The wonder, however, is, not that a searcher of such penetration as Pasteur should have discovered the facets of the tartrates, but that an investigator so powerful and experienced as Mitscherlich should have missed them. The idea of molecular dissymmetry, introduced by Biot, was forced upon Biot's mind by the discovery of a number of liquids, and of some vapours, which possessed the rotatory power. Some, moreover, turned the plane of polarisation to the right, others to the left. Crystalline structure being here out of the question, the notion of dissymmetry, derived from the crystal, was transferred to the molecule. ' To produce any such phenomena,' says Sir John Herschel, * the individual molecule must bfe conceived as un- symmetrically constituted.' The illustrations employed by M. Pasteur to elucidate this subject, though well calculated to give a general idea of dissymmetry, will, I fear, render but little aid to the reader in his at- tempts to realise molecular dissymmetry. Should difficulty be encountered here at the threshold of this work, I would recommend the reader not to be daunted ])y it, or prevented by it from going further. He may comfort himself by the assurance that the conception