ON ACETIC ACID AND ACETATES. 347 



forms with the spirituous and volatile part of their re- 

 spective products. 



It is of little importance to know whether prussic acid Found perhaps 

 or ammonia be contained in the products of acetates form- was i m p Ure , 

 ed by an impure acetic acid like vinegar; for the extractive 

 or mucilaginous matter might furnish either, without the 

 acetic acid contributing to it. But as this acid is frequent- 

 ly the last result of the destructive distillation of vegetable 

 substances, it is essential to know, whether it contain 

 nitrogen. 



In all the products of the distillation of acetates, but Brown fetid ofl 

 particularly those that yield most pyroacetic spirit, we rom acetate *« 

 find a brown, fetid oil; but I have taken no notice of this 

 in the table. 



I endeavoured to modify the products of the distillation Acetate of lead 

 of the acetate of lead, by mixing with it other substances, c^ai-coal™ 

 either oxidating, or disoxidating. The acetate of lead 

 mingled with a fourth of charcoal yielded 42.5 of pyro- 

 acetic spirit by distillation : and the same salt mingled with and *ith oxide 

 a fourth of black oxide of manganese yielded but 34. Their ganese. 



specific gravities were 0-9606 and 0*9633; and their ratio 

 of acidity 2*445 and 2-052. 



The acetate of lead describe I by Thenard yielded 59 of 

 pyroacetic spirit ; 3*973 of acidity ; and tfte spec. grav. of 

 the whole liquid product was 0*9302. 



It is certain, that heat alone is not sufficient, to convert Heat alone 

 acetic acid into pyroacetic spirit; but that the concurrence oesnotcon - 



rj s * vert pyroacetic 



of other circumstances is necessary, which we are not yet acid into pyro- 

 able to ascertain. Into a porcelain tube, at a strong red acetlc spmt ' 

 beat, I passed acetic acid of the spec. grav. 1*0635, and 

 tlffc acidity of which was 60*624 The porcelain tube was 

 luted to a tubulated matrass, and in the tubulure were 

 placed two tubes. One of these, be ng open at both ends, 

 allowed me to drain out the liquor, that condensed in the 

 matrass, by means of a little pipe. The other, which was 

 curved, reached to the bottom of a phal containing a solu- 

 tion of barytcs, and communicating withapneumatocherwical 

 trough. I continued the process eight hours, constantly 

 returning into the retort the liquid that condensed in the 

 matrass; so that ultimately each particle had passed five or 



six 



