

31S ON ACETIC ACID AND ACETATEf. 



tix times through a tube heated red hot for the space of 

 six inches. Carbonic acid and carbnretted hidrogen gas 

 were continually evolved. The liquid that passed into the 

 matrass became more and more brown, and a small quan- 

 tity pt coally matter was left in the retort. The weight of 

 the acid was then 1'0443, and the proportion of its acidity 

 was only 33*65. No pyroacetic spirit was formed. Acetic 

 acid therefore is capable of supporting a great heat, with- 

 out being totally decomposed, aud is at the same time highly 

 volatile. For this reason it is almost always a result of 

 the destructive distillation of vegetable and animal sub- 

 stances. 

 Heat diminishes It is to be observed that the acidity of the acetic acid, 

 ^ c ^ s lt g y ra ^ e that has passed through a red hot tube, diminishes much 

 more than ils specific gravity. This is analogous to what 

 happens in the result of distilled acetate of nickel. The 

 cause I know not. I could not find any oil or other sub- 

 stance in these liquids ; if they contain any other acid than 

 the acetic, it must differ from this in a very few properties, 

 for all those I examined agree perfectly with those of acetic 

 acid. 

 Vapourof If carbon be introduced into the red hot porcelain tube 



acetic acid before the vapour of acetic acid is passed through it, nothing 

 i&arcoal. is collected, even after a single distillation, but water, car* 



bonic acid, and carburetted hidrogen gas. 

 The spirit ob- The distillation of some other salts formed by vegetable 



tained from acids leads me to believe, that the acetic is the only acid, 



acet'C acid 



alone; the salts of which furnish pyroacetic spirit by distillation. 



not from tar- I have distilled tartrate of copper and lead, and acid 



t* ric > tartrate of potash. I have treated the products in the same 



manner as I did those of the acetates, but in no instance dfti 

 I perceive any traces of the pyroacetic spirit. 



oxalic, The acid oxalate of potash also afforded me none. On 



comparing all the products of the distillation of the tartrate 

 and oxalate of potash, I believe, that the tartaric acid dif- 

 fers from the oxalic chiefly by containing a larger propor- 

 tion of carbon. 



•r citric. I could not obtain any pyroacetic spirit from the distilla- 



tion of citrate of potash. 



A? 



