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Of the COMPOSITION and PROPORTION of CARBON 

 in BITUMENS and MINERAL COAL. By RICHARD 

 KIR WAN, Efq\ L.L.D. F.R.S. and M.R.LJ. 



x\, N exa£l knowledge of the component parts of the different Read Decem- 

 Ipecics of mineral coal, and alfo of bitumens (fubflances which j^.^'f''' 

 moft of them contain ;) forms an objeft of fome importance not 

 only to the naturalift, whofe views are merely fpeculative, but to 

 the practical oeconomift, who wifhes to extrad from each fpecies 

 all the advantages it is capable of yielding, and to be enabled to 

 compare the various kinds afforded by different countries, in 

 order to obtain and employ that which fhall on the comparifon 

 appear to him beft fuited to his intentions. 



In effedt coals are not only applicable to the more ufual pur- 

 pofcs of combuflion, an ufe, fimple as it may appear, attended 

 according to their various fpecies with a confiderable difference 

 of calefadive power both in intenfity and duration, but alfo to 

 the produdion of varnifhes, much more advantageoully applicable 

 in many inflanccs than thofe extraded from the vegetable king- 

 dom, 



