1 5 Darraccfs ObfcrvatloUi 



loured, in which floated a. kind of oil, the quantities of which 

 were apparently equal. After flrongly urging the fire, there 

 remained in the two retorts black refiduums, which [ treated 

 with boiling water as in the firil experiment. The charcoals 

 remaining in the filters were dried in a flove, and then 

 weighed : that produced by the acetate of foda weighed eight 

 parts, and that produced by the acetite eight parts and a 

 half. Thefe two refiduums when examined were found to 

 be charcoal, fimilar to that obtained by the acetite and ace- 

 tate of potafh. This experiment, which on account of the 

 cryflallization of the falts ought to be confidered as correct, 

 iince the proportions of the constituent parts of the falts were 

 found to be the fame, explains what we have already an- 

 nounced, why the acetite of potafh gave a little more char- 

 coal than the acetate. There is reafon, no doubt, to believe 

 that it arofe from the greater or lefs deficcation of the falts, 

 and the manner in which they were burnt, fince in the fe- 

 cond experiment I found not only the fame quantity of char- 

 coal in the refiduum of the acetate of foda, but even a frnall 

 quantity more than in the acetite. 



Exp. III. Being perfuaded, by the remits of thefe two ex- 

 periments, that the acetous was not more carbonized than the 

 acetic acid, I made as a new proof the following experiment : 

 I put equal parts of fulphate of copper and acetite of lead, both 

 cryftallized, pulverized, and mixed, into a retort, which was 

 placed in a furnace over an open fire, joined to the retort an 

 adapter and a receiver, and to the latter a bent tube to collect 

 the elaftic fluids. At a very gentle heat there palled over a 

 white liquid, which increafed without changing its colour : 

 the fire being continued a confiderable time that I might 

 obtain all the acetic acid, no other gas pafled over but a part 

 of the air of the veffels; the heat was continued till the glafs 

 retort began to enter into fufion, upon which it was taken 

 from the fire. There remained a refiduum of a reddifh vel- 

 lovv colour, the weight of which was equal to two-thirds that 

 of the mixture employed: the liquid obtained had a perfect 

 refemblance to pure acetic acid, its weight was equal to a 

 third of the quantities employed. A fimilar experiment is 

 defcribed in the Annales de Chimie by C. Badolier; but its 

 object, indeed, was different from that of the prefent one, it 

 was publifhed merely for the purpofe of giving a Ample and 

 economical procefs for obtaining radical vinegar. The au- 

 thor, however, obferves very juftly that no carbonic acid was 

 difengaged, as was the cafe in my operation ; nor did I ob- 

 tain a fingle atom of acid gas. I endeavoured alio to difcover 

 whether any carbon remained in the refiduum ; a rigorous 



examination 



