4^ Q» the Identity of the Pyromucous, 



not .Vole to obtain the real diftinguifhing characters of the 

 pvromucous acid* 



TIL Cbaraflt-rs afefibed to the Vyrotartareous Acid. 



We are indebted to Letuery and Neumann for our firft 

 knowledge of this acid, fufniihcd by diflilled tartar, and dif- 

 ferent from the t-a-rtareoas acid, They found that tartar, by 

 di (filiation, ga\e the fourth of its weight of ackl phlegm. 

 According to the prescription of Neumann, it was to be rec- 

 tified at a gentle heat; but C. Guvton was not able to per- 

 form that operation with faccefs, and the retort was always 

 broken by the esplofion which took place. The empyreu- 

 matic odour and taite of this acid are the two moll finking 

 characters which made it be admitted by chemifts as a pe- 

 culiar acid. It is difficult to conceive why Venel ihould take 

 this acid product of diftilled tartar to be nitric acid, which 

 be thought might be extracted alone f and in a liate of pu- 

 rity. It is no lefs aftonifhing to hear C. Monnet maintain, 

 in confequence of experiments made at fome length, that 

 diftilled acid of tartar is muriatic acid, though he really found 

 in it, according to his own acknowledgement, only approxi- 

 mative characters. The academicians of Dijon and C. Ber- 

 thollet, after repeating all the experiments of Monnet, were 

 convinced that there is no real analogy between the acid 

 product of diftilled tartar and the muriatic acid. Scheele, in 

 proving that there is always a little real muriatic acid in the 

 alkali of tartar, infiftcd on the differences between this acid 

 and that of tartar. M. Fontana proved that the acid diftilled 

 from tartar can be entirely refolvcd into carbonic acid gas 

 and carbonated hydrogen gas; fo that, by bringing it nearer 

 to all the other vegetable acids, he removed further every idea 

 of confounding it with the mineral acids. In the laft place, 

 Guvton, in the firft part of the firft volume of the Diclion- 

 nanf di Chimie Eticj 'dope digue, publiftied in 1786, after de- 

 tailing all the different opinions as well as the principal facts 

 known refpecf ing this acid, concluded that it would be ne- _ 

 ccftary to confider it as a peculiar acid; a product of tartar 

 altered by heat, diftinguifned from the latter by its being 

 incapable of cryftallifation, and by the foluble fait which it 

 8 former 



