DISSYMMETRY OF CELLULAR LIFE 29 



is dissymmetry of construction but not molecular 

 dissymmetry. 



One could put in the same category as quartz other 

 minerals or salts, such as sulphate of magnesium and 

 formate of strontium, substances having crystals with 

 hemihedral facets but the solutions of which are not ac- 

 tive. In short, no product of inorganic nature or of the 

 chemistry of the laboratory deviates the plane of polar- 

 ization of light when in solution; it is only the products 

 of living nature which have this property but they possess 

 it to a very marked degree and carry it with them when 

 they enter into combination with other substances. 



Since then, the chemistry of synthesis has made 

 progress, and today, starting, like the plant, \^dth water, 

 carbonic acid and ammonia, and putting into play only 

 the forces and ordinary resources of the laboratory, we 

 are able to manufacture artificially the majority of the 

 natural organic products. Is it necessary, therefore, to 

 change some of the conclusions which Pasteur announced 

 in 1850? Yes, one thing only which he did not foresee. 

 We are able now, by the aid of primitively inactive bodies 

 to rhanufacture active ones, to thus produce dissym- 

 metry and the rotary power in the molecule which we 

 construct. With inactive succinic acid we can ascend, 

 for example, to tartaric acid. But when a chemist 

 manufactures thus artificially the right-handed tartaric 

 acid he makes also necessarily and simultaneously the 

 left-handed form, so that the combination which comes 

 from his hands is inactive. Nature alone has the secret 

 of manufacturing one without producing the other. In 

 the grape, for example, she gives us commonly the right- 

 handed tartaric acid and not the left, or at least rarely 

 the left, since paratartaric acid, the combination of the 

 right and the left, sufficiently abundant at one time to 

 obstruct the works at Thann, has almost disappeared 

 5 



