[ 285 ] 



XLVI. Chemical Notices from Foreign Journals. By E. Atkin- 

 son, Ph.D., F.C.S., Teacher of Physical Science in Cheltenham 

 College. 



[Continued from p. 136.] 



SOME communications on lactic acid have brought to hght 

 several interesting facts relative to this acid. 

 By some chemists lactic acid is considered to contain 6, and 

 by some 12 atoms of carbon. The discovery by Strecker of its for- 

 mation from alanine, C^ H^ NO'*, and Wurtz's observation that 

 it is formed by the oxidation of propyle-glycol, C^ H^ O'', lend a 

 support to the former view. In some experiments undertaken with 

 the expectation of giving additional weight to the idea that lactic 

 acid was bibasic, and contained 6 equivs. of carbon, Wurtz* tried 

 the action of pentachloride of phosphorus on lactate of lime, and 

 obtained thereby an organic chloride, C^ H'' 0^ CF, which he 

 named chlorolactyle. It stands to lactic acid in the same rela- 

 tion as chloride of acetyle to acetic acid. Wurtz found that by 

 treatment with bases this substance regenerated lactic acid, and 

 by treatment with alcohol it yielded an etherial compound, 

 Qio JJ9 04^ CI, which he considered to be chlorolactic ether, and 

 he expressed its formation as follows : — 



C«H4 02CP + 2C'»H«02=C'*H5Cl + 2HO + ^ ^4^5 ^0^. 

 Chloride of Alcohol. Chloride of p, -^ 



lactyle. ethyle. ^^ 



In repeating Wurtz's experiments, Ulrichf observed certain 

 reactions which led him to the conclusion that Wurtz's chloi'olac- 

 tyle was the chloride of chloropropionyle, C^ H^ ClO^, CI, derived 

 from propionic acid. He found when this substance was treated 

 with water alone, that it was resolved into hydrochloric acid and 

 chloroprop ionic acid, — 



C« H4 CI 02, CI + 2 HO = HCl + C6 H^ CI 0^ 



Chloride of Chloropropionie 



chloropropionyle. acid. 



Ulrich observed that chloropropionie acid, when treated with 

 nascent hydrogen, was convei'ted into propionic acid; and he 

 found that this reaction furnished the best method of preparing 

 propionic acid. 



In a communication on the constitution of lactic acid, Kolbe % 

 expresses the opinion that lactic acid, and the acids homologous 

 with it, containing 6 equivs. of oxygen, are derived from the 

 volatile acids containing 4 equivs. of oxygen, by the substitution 



* Liebig's Annalen, August 1859. Comptes Rmdiis, vol. xlvi. p. 1228. 

 t Liebig's Annalen, March 1859. J Ibid. 



