5 2 THE POPULAR SCIENCE MONTHLY. 



an optical isomery identical with that of malic and tartaric acids. 

 Sometimes the sugars present a right isomery, a left isomery, and 

 an isomery inactive "by compensation, and a splitting into two 

 sugars, one right and the other left. This is exactly what we 

 have witnessed in right and left tartaric acids, the union of which 

 constitutes paratartaric acid, inactive by compensation. It is not 

 useless to insist upon this resemblance, and to remark that the 

 reactions which have permitted us to effect the synthesis of the 

 principal sugars are of a purely chemical character, and that they 

 demonstrate that the chemist can reproduce substances endowed 

 with the rotatory power and aside from all intervention of life. 

 The sugars, reproduced by synthesis, remain proteic or albuminoid 

 substances. Here, again, the prophets of vital force are found 

 wanting. 



M. Grimeux in 1885 had prepared synthetically, by the action 

 of oxychloride of phosphorus upon a mixture of leucine and 

 tyrosine, and further treatment with NH 3 (ammonia), an amor- 

 phous, colloid substance, offering some of the characteristic reac- 

 tions of albumen: precipitation on ebullition, the xanthoproteic 

 reaction, the reaction of Millon, and the biuret reaction (soda and 

 sulphate of copper). But M. Schutzenberger has just made a 

 considerable step in the synthesis of those substances. A note in 

 the Comptes rendas of the Institute of January 26, 1891, exposes 

 the results of a successful experiment in the synthesis of a pro- 

 teic substance presenting all the physical and chemical character- 

 istics of the peptones. 



An extended series of researches on the products resulting from 

 the decomposition by hydration of proteic substances, albuminoid 

 or other, under the influence of alkalies (baryta), have led M. 

 Schutzenberger to attempt the synthesis of a proteic substance, 

 starting from the simple terms of its decomposition by hydration. 

 After numerous fruitless attempts he succeeded in forming a 

 nitrogenous compound, which by its characteristics should be 

 placed in the class of proteic substances, by combining, with the 

 elimination of water, the ultimate and crystallizable products 

 arising from the decomposition of albumen and fibrin under the 

 influence of baryta. After a series of operations, of which I do not 

 recite the detail, Schutzenberger obtained an amorphous prod- 

 uct, soluble in water, precipitable by alcohol into white, cheesy 

 lumps. The body thus obtained exhibited great characteristic 

 similarities with the peptones. Its physical characteristics, its 

 chemical reactions, and its modifications under the influence of 

 heat, were faithfully like those of proteic substances. A great 

 advance has therefore been made toward synthesis of organic 

 substances, and the future promises still more complete results. 



The chemist has then been able to realize the construction of 



