between the Acetous and Acetic Acids. 33$ 



bis opinion fecmed fo conclufive, that all chemiils almoft 

 were eager to adopt it. The pneumatic chemifts, explaining 

 this opinion in the language of their theory, have laid that 

 the acetic acid is the acetous combined with a new quantity 

 of oxygen ; confequently, in a ftate of more perfect combina 7 

 tion. Such has been the opinion hitherto generally adopted* 



C. Adet, in a memoir read before the National Inftitute, 

 and inferted in Vol. XXVII. of the Annales de Cbimic, op- 

 pofes this opinion, and maintains: 



1 ft, That no fuch acid as the acetous exifts. 



2d, That the acid of vinegar continually prefents kfelf at 

 the higheft. decree of oxygenation to which it can attain ; 

 and confequentTv, that it is always in the ftate of acetic acid. 



3d, That the difference which exifts between the acetic 

 acid extracted from the acetate of copper, and that extracted 

 from vinegar, depends on the lefs quantity of water contained 

 in the latter. 



Has C. Adet completely attained the end which he pro- 

 pofed ? In my opinion he has not. In the firft place, the 

 greater part of the experiments on which the opinion of Ber- 

 thollet refts, have not even been attacked, and confequently 

 remain in full force. Such are : 



lft, The pungent odour and tafte which this acid retains 

 though diluted with water fo as to make its fpecific gravity 

 equal to that of diftilled vinegar j an odour and tafte which 

 the latter does not poffefs. 



2d, The property which the acetic acid has of immediately 

 combining with copper, while the acetous acid does not 

 combine with it until it has been oxidated. 



In the next place, the proofs which this chemift brings to 

 fupport his opinion, are far from being fo conclusive as might 

 be wiflied. C. Adet himfelf allows that they ftill leave fome 

 defiderata. 



I propofed to prefent fome' objections to the opinion of 

 C. Adet, and to prove that it cannot be admitted. I even 

 had written a paper on the fubjec~t; but C. Chaptal, in his 

 observations printed in Vol. XXVIII. of the Annales de 

 Cbimie, having difeharged this talk much better than I 

 could have done, I have thought proper to fupprefs the 

 greater part of my labour; I fhould even have fuppreffed it 

 entirely, if the experiments I made, and the refults J obtained, 

 had not led me to adopt an opinion different from that of 

 Chaptal. It is this part of my labour that I have determined 

 to give. 



C. Chaptal, after having proved, by feveral experiments, 

 which appear to me decifive, that the difference between the 



two 



