S32 Acid Liquidjrom Potash and Alcohol. 



has been found, that when a solution of potash in alcohol is 

 exposed to the contact of atmospheric air, oxygen is absorbed ; 

 and that the deep brown colour, which it has been long known 

 is assumed by such a solution, is owing to the formation of a 

 red matter, which may be separated in the solid state by satu- 

 rating the potash with an acid, and which has been supposed to 

 be of the nature of a resin. These facts 1 had occasion to ob- 

 serve before I had any knowledge of the experiments establish- 

 ing them, which have been recently published on the subject; 

 but I do not wish to enlarge on them at present, as the object 

 which I have more immediately in view, is to determine whether 

 any products of an acid nature result from the action of potash 

 on alcohol, and what these products are. 



1. Acid Liquid front' Pdtash and Alcohol. — Berzelius, in his 

 Treatise on Chemistry, observes, that it had been said that acetic 

 and carbonic acids were produced during the action in question ; 

 but adds, that he was not aware of any special research on the 

 subject, although it was known that the solution did not deposit 

 any carbonate of potash *. Subsequently to these observations 

 of Berzelius, M. Hess, in the course of his researches, made 

 some experiments, with the special view of ascertaining whether 

 acetic acid resulted from the action. He evaporated a consider- 

 able quantity of an alcohoHc solution of potash ; and on treating 

 the residue with sulphuric acid, he states, that he did not find 

 that any acetic acid was disengaged. In making similar expe- 

 riments, however, I had uniformly observed, that on adding 

 sulphuric acid to the residue of the evaporation, a pungent odour 

 was disengaged, having a strong resemblance to that of acetic 

 acid in its less concentrated forms ; and I was therefore strongly 

 induced to suspect that a portion of this acid, really did result 

 from the action. 



The first instance in which I made a direct and careful re- 

 search to ascertain the fact, was with a portion of an alcoholic 

 solution of potash, which had been kept in a corked bottle for 

 several months, and had long acquired a deep brown red colour. 

 This solution was poured out into an evaporating dish, and al- 

 lowed to stand exposed to the air for some days, till the alcohol 

 was evaporated away. The water was then farther evaporated 



t Lehrbuch der Chemie, iu. 992. 



