]g2 MR. HATCHETX'S OBSERVATIONS 



But it is very remarkable, that neither the allies obtained from 

 the charcoal of the Bovey coal, nor thole obtained from 

 the leaves of the Iceland fchiftus, afforded the fmalleft trace of 

 alkali.* 



B. 200 grains of the Bovey coal, reduced to powder, were 

 digefted in boiling diftilled water, which was afterwards filtrated, 

 and examined ; but I could not difcover any figns of extract, 

 or ot' any other fubftance. 



C. 200 grains were next digefted with fix ounces of alcohol, 

 in a very low degree of heat, during five days. A yellowiih- 

 brown tincture was thus formed, which, by evaporation, af- 

 forded a deep brown fubllance, poffefiing all the properties of 

 refin, being infoluble in water, but foluble in alcohol, and in 

 ether ; it alio fpeedily melted, when placed on a red-hot iron, 

 burned with much flame, and emitted a fraganl odour, totally 

 unlike the very unpleafant fmell produced by burning the coal 

 itfelf, or by burning any of the common bituminous fub- 

 ftances. The quantity, however, which could be extracted 

 from 200 grains of the coal, by alcohol, was but fmall, as it 



- did not exceed S grains. But this (mall quantity was fufficieiit 

 to prove, that although the Bovey coal does not contain any 



" vegetable extraft, like the fchiftus formerly mentioned, yet the 



whole of the proximate principles of the original vegetable 



have not been entirely changed; as a fmall portion of true refin, 



not converted into bitumen, itill remains inherent in the coa!, 



although the bituminous part is much the moft prevalent, and 



caufes the fetid odour which attends the combuftion of this 



fubfiance. 



It refembles the Upon a comparifon of the general external characters of the 



fchiftus in its Bovey coa!, with thofe of the fubfiance which forms the leaves 

 produces as well . , . . T . . .. , . n r , , ... 



as character- contained in the Icei3nd fchiftus, a very great relembiance will 



but it afforded De obferved ; and this is farther confirmed, by the fimilarity of 



no extract, but 

 •nly refin 



the produces obtained from each of them in the preceding ex- 

 periments, with the tingle exception, that the leaves contain 



* This, as far as relates to the Bovey coal, has been alfo no- 

 ticed by Dr. Milles, Phil. Tranf. Vol. LI. p. 553. But wood, 

 however long fubmerged, is not deprived of alkali, unlefs it has 

 more or lefs been converted into coal ; for I have, fince the read- 

 ing of this paper, made fomc experiments on the wood of the fub- 

 merged foreft at Sutton, on the coaft of Lincoln fhire, and have 

 found it to contain potafh. 



fom# 



