M. Louren9o on some new Polyethylenic Alcohols. 293 



an acid potash salt is obtained which closely resembles cream of 

 tartar. The salt is anhydrous, and contains € 4 H 5 KG 5 . 



The oxidation of triethylenic alcohol is accompanied by the 

 same phenomena as that of diethylenic alcohol. By suitable 

 treatment two lime-salts are obtained : one, slightly soluble in 

 cold water, is identical with that just described ; the other is 

 more soluble in water, and forms silky tufts like asbestos. The 

 composition of this salt is € 6 H 8 Ga 2 O 6 . Its aqueous solution 

 gives a white precipitate with nitrate of silver ; this precipitate, 

 decomposed by sulphuretted hydrogen, yields a liquid which 

 contains a new acid, and which does not crystallize, but after 

 evaporation forms a syrupy mass. 



Comparing these acids with the polyethylenic alcohols from 

 which they are formed, relations of a very simple character are 

 found to exist between them, analogous to those which exist 

 between alcohol and acetic acid ; a certain quantity of hydrogen 

 disappears and is replaced by an equivalent quantity of oxygen. 

 When glycol is transformed into glycolic acid, we may assume 

 that the radical ethylene, € 2 H 4 ,is changed into glycolyle, C 2 H 2 0; 

 in the case of diethylenic alcohol, we may suppose that both the 

 ethylene radicals are converted into glycolyle. Diethylenic 

 alcohol thus becomes diyly colic acid. The acid formed from tri- 

 ethylenic alcohol is similarly derived ; two ethylene radicals are 

 converted into glycolyle, while the third remains intact. In this 

 manner diglycolethylenic acid is obtained. The following formula? 

 exhibit these relations : — 



Other acids may be formed from these polyethylenic alcohols. 

 Those here described possess the molecular complication and the 

 characters of the true vegetable acids, and they have been gra- 

 dually built up by synthesis from olefiant gas. 



Some additional members have been added to the series of 

 polyethylenic alcohols by Lourenco*. In his original method 

 * Comptes Rendus, September 3, 1860. 



