tn the Acetic and Acetous Acids : 19 



entered into ebullition, on account of the heat produced by 

 the calcareous fait in folidifying the major part of the water 

 contained in the vinegar." During this diftillation there 

 pafled over a clear liquor, which fell in ftrise on the fides of 

 the adaptor, and which was collected in a receiver. This 

 liquor totally changed in appearance ; had a ftronger and 

 more pungent favour than the acetous acid employed, and 

 its odour was (harper and more penetrating : one might have 

 taken it for diluted radical vinegar. This product, when 

 fubjefted to a fecond diftillation with dried muriate of lime, 

 acquired a little more ftrength : after a third and a fourth 

 rectification, a tranfparent liquor was obtained, of an odour 

 and favour very fimilar to that of common acetic acid. 

 During thefe rectifications, not an atom of charcoal was 

 depofited. To afecrtain whether the acid obtained, in lofing 

 a great quantity of its water, had loft alfo the mucilaginous 

 matter which accompanied it, I faturated a portion with 

 cryftallized carbonate of potafti : in vain did I add an excefs 

 of this fait, for nothing was precipitated ; whereas common 

 acetous acid, by a fimilar faturation, precipitates a flaky 

 matter, which is collected in the bottom of the veffel em- 

 ployed. 



Though the flrong and penetrating odour of the acetic 

 acid obtained by the flmple means above defcribed was fuf- 

 ficient to induce me to conclude that it was really fimilar to 

 that obtained from metallic acetites, I endeavoured to ascer- 

 tain this fa& bv a new experiment. For that purpofe 1 took 

 equal parts of this radical vinegar and of alcohol to try to 

 make acetic ether : the attempt was not unfuccefsful; and, 

 by Pelletier's procefs, I obtained an ether perfectly agree- 

 able, and having an exact refemblance to the acetic ether 

 found in laboratories. I muft here obferve, in fpeaking of the 

 acetic acid obtained by rectification alone with muriate of 

 lime, that it is far more agreeable than the acetic acid pro- 

 duced, for example, by the diftillation of metallic acetites; 

 and efpeciallv when they are diluted with water. The latter 

 then aflhmes a difagreeable empyreumatic odour, and an 

 oily favour, arifing from a portion of acetic acid which has 

 been decompofed by the heat, and which has given birth to 

 a kind of oil which the acid retains in combination. The 

 other, on the contrary, paiTes only to the ftate of common 

 acid of vinegar bv preferving an agreeable pungency. Be-* 

 fore any conclufion can be drawn from theprecediug refults, 

 I muft: not forget, to mention an interefting fadt remarked by 

 C. Pontier. This able chemift and mineralogift, who dif- 

 covered the chromate of iron in France, fent, about eight 



B 2 months 



