lilSTORV OF PltCOAt^ ifS 



Acid of 35° or 40®, heated with fir or elm charcoal, at Nitric aciddisl- 

 first i^ives out the gasses, that might be expected: but at a ^olves char- 

 certain point the gasses cease to be formed, and the char- 

 fcoal enters into solution. I have very old solutions of this 

 kind, that are h(it altered. Alkalies precipitate nothing 

 from them, because charcoal, either oxided or in a state of 

 simple division, is as soluble in alkalis as in acids. I had 

 proceeded thus far, when I learned from the Chemical An^ 

 nals, that tannin was formed by the soliition of carbonaceous 

 substances. I believe Crell is the first, who announced the 

 solution of charcoal in nitric acid. 



A hundred grains of Villanueva coal, ^reated with concen- ^?^}- treated ^^ 

 trated sulphuric acid, and perfectly washed and dried, left acid. 

 104. Was this coal oxided ? T find nothing mentioned in 

 my notes, but that it burned withotit any bituminous smelly 

 that of sulphur only being noticeable. 



Turf, 



A Piece of turf froiri Dax afforded me the following re- Tuif 



suits. 



A hundred parts left 40 of charcoal without any change yields -40 of 



of bulk. Its products were water, and vinejrar mingled c^^""^?^'' '^^' 

 . f» 1 • t • . t^r, vinegar, 



v/ith ammonia, the taste of which did not differ from that of ammonia, 



wood : but a yellow oily vapour came over, that became hard and '6 of a se- 



like suet, which does not commonly occur in the distillation baceous oil, 



of wood. This suet was from 6 to 6| per cent. I did not 



examine the gasses. 



Potash, which lias not the least action on pitcoal, to my Potash dis* 

 astonishment perfectly dissolved the turf. The solution jg ^^^ ^^^ ^"'" • 

 coffee-coloured. Acids decompose it, thrbwing down a 

 brown fiocculent precipitate, which distillation renders black, 

 shining, and fragile. When distilled it is converted into 

 charcoal, without softening or diminishing in bulk ; yields 

 the butyraceous product; and is reduced to '50 of char- 

 coali 



Nitric acid at 30'^ does not decompose turf, as it does pit- ]sjit,i(. acid 

 COai. Washed and dried it affords water, and the butyra- ^o-s not du. 

 ceous matter, but no acid* It might be supposed, that this ^°"^P^^^ ^^' 

 suet exists ready formed ia turf. This- deserves to be far- 

 ther 



