;382 Examination of four specimens of Darjeeling Coal. [No. 4. 



coals, but still like very finely granulated gunpowder. When this 

 powder is heated in a close crucible, for ascertaining the gaseous 

 contents of the coal, it changes from a shining black to a bright 

 black steely powder. 



It flames well in the forceps, but does not melt or alter its shape, 

 remaining a long time red hot till the exterior is a coat of reddish 

 ash ; the smoke from the crucible is also highly inflammable. 



The smell of the smoke is very peculiar, having nothing pungent 

 or peaty, but being almost aromatic, so as to induce us to suppose 

 that it contains a portion of succinic acid. It barely discolours a 

 silver crucible, shewing thus that it contains no sulphur. Its streak 

 is a dull black. 



It is not at all sectile and only crumbles before the knife, differ- 

 ing in this from the former Darjeeling specimen, Journal Vol. XXII. 

 p. 313 which was a true jet coal. 



The ash is a dark fawn-coloured, but very light, powder, from which 

 muriatic acid dissolvesaportion of iron,leavinganashcolouredresiduum. 



There is no effervesence, showing the absence of lime. 



It cokes to a bright crumbling cindery mass, of which the fragments 

 incline more perhaps to the cubical than to any other form, but are 

 really of all shapes. The larger pieces preserve their shape a little, 

 though considerably swelled and split, but few will bear more than 

 careful handling. 



Its specific gravity is, 1.32. 



1 00 parts of this coal contain : 



Water, 6.80. 



Gaseous matter, 29.20. 



Carbon, 61.10. 



Ash, 2.90. 



100.00. 



The brittleness of this coal and its tendency to absorb moisture, 

 together with the utter friability of the coke, are considerable 

 drawbacks to its economical value. It is in effect from its great 

 purity, readiness to flame, and steady combustion, a very valuable 



