504 



acid was admitted into the list of vegetable acids in all systems 

 of chemistry published at that period. 



" In two years after (1817) M. Braconnot, a celebrated 

 continental chemist, read a paper in the Royal Society of 

 Nancy, on sorbic acid, which was published in the Annales de 

 Chimie et de Physique (vol. vi. p. 239). In this communica- 

 tion he expressed his opinion that sorbic acid is different from 

 malic and all others. He gave an economical process for pre- 

 paring it, and described many of its combinations and their 

 constitution. 



" In the same year M. Vauquelin published experiments 

 on this subject, in the same volume of the Annales de Chimie 

 et de Physique (p. 337). He, as well as Braconnot, admitted 

 the sorbic acid to be a new and peculiar one ; and declared, as 

 the result of his inquiries, that malic acid, so far from being 

 the only and proper acid of the berry of the Sorbus aucupariaf 

 as Scheele had supposed, is not present in that fruit, he having 

 found in it no other than the sorbic. He adopted the process 

 given by me for preparing sorbic acid ; described some of its 

 properties and combinations, along with their analysis. 



" Braconnot, who at first admitted the sorbic to be a new 

 acid, had, meanwhile, continued his investigations, and in 1818 

 announced some new facts which had caused him to modify his 

 opinions. His paper was read in the Royal Academy of Sci- 

 ences, and published in the eighth volume of the Annales de 

 Chimie et de Physique (p. 149). In this paper he described a 

 vegetable proximate principle, detected by him in the juice of 

 the houseleek plant, which he conceived to hold a middle place 

 between gum and sugar, and which possesses so powerful an in- 

 fluence in masking the combinations formed by sorbic acid that 

 a sorbate of lead containing a very small quantity of it refused 

 to crystallize. He adds : ' I believe I may conclude from ray 

 experiments that the malic acid of Scheele is composed of at 

 least two substances, viz., sorbic acid, and this abundant mucous 



