Preparation of Aldehyde and Acetic Acid. 21 
duct, and specifies briefly the manner in which he conducted the 
process. As however his method is not noticed in other chemi- 
cal works, and as our mode of proceeding and some of the re- 
sults we have obtained, are, we think, not without novelty 
and interest, we deem them worthy of a brief ane in wwned 
Journal. 
When alcohol j is added to a strong aqueous patie. of arene 
acid in aretort, a very brisk reaction ensues, and upon applying a 
gentle heat hans passes over a clear liquid, containing a consider- 
able amount of slssabeychoy with a faint trace of acetic and probably 
formic acids. The presence of the aldehyde is readily shown 
by adding a pee drops of the liquid to a solution of nitrate of 
silver previously curdled. by ammonia, and then gently heating 
the mixture. ~The oxide is speedily reduced, forming a brilliant 
metallic coating on the sides of the glass. 
Substituting for the chromic acid of this experiment, a mixture 
of bichromate of potassa and sulphuric acid, and blending with 
this a quantity of common alcohol, the reaction is extremely 
violent, a large volume of carbonic acid is evolved, and the liquid 
which distils over, contains, with other products, much aldehyde 
and acetic acid. To obtain either of these substances but little 
mingled with the rest, special attention must be paid to the pro- 
portions in which the bichromate, sulphuric acid, and alcohol are 
mixed, and to the order in which they are brought together. 
Thus, in all our experiments, we found, than when alcohol is 
added in small quantities at a time to a mixture of the bichromate 
and sulphuric acid the distilled product is almost pure acetic acid, 
but when sulphuric acid is slowly dropped into a mixture of the 
salt and alcohol, the liquid which passes over contains little else 
than aldehyde. 
irene remarkable. differentea i in the products is, we think, readily 
explained by the different intensity of the oxidating power in the 
ewer eases. In the former, the alcohol, as it fallsinto the mixture 
of bichromate and. sulphuric acid, t yund ,d on all sides 
by free chromic acid, is carried rapidly. ily through the lower stages 
of oxidation, corresponding to aldehyde and. aldehydic acid, un- 
eg by the addition in-all of 4 equivalents of oxygen, and the 
n of 2 equivalents of water, it is converted into acetic 
acid, in the latter case, the sulphuric acid, dropping slowly into 
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