58 MALLET : GEOLOGY OF DABJILING AND WESTERN DUARS. 



It may be confidently asserted that no risk is to be apprehended 

 from fire-damp within any distance from the surface that the mines are 

 likely to attain. As such is practically unknown in the Damuda coal 

 of the Raniganj mines,* there is little to fear from the same coal after 

 it has lost two-thirds or three-quarters of its volatile matter, from the 

 disengagement of which the fire-damp originates. It is no doubt 

 possible that some of this disengaged gas may still remain stored up 

 at a considerable depth, but it is highly improbable, taking into account 

 the disintegrated state of the coal and the disturbed condition of the 

 beds it occurs in. 



Another point in favor of the Darjiling coal is the almost total 

 absence of trappean intrusions, which do great injury to the seams in 

 some of the fields south of the Ganges.f 



If the results of the trial drifts should prove sufficiently encourag- 

 ing to warrant an attempt to work the coal on a 

 commercial scale, the neighbourhood of Selim 

 Hill would be the most favorable place at which to begin operations. 

 Out-crops of fair thickness occur more plentifully there than along 

 most other parts of the Damuda band, and the Chirankhola and Tindharia 

 seams, which are amongst the thickest yet known, are close to the cart- 

 road, although several hundred feet below it. As a temporary measure, 

 the coal could be brought up to the road on mules or cattle, along paths 

 which would cost a very trifling sum, and then carted down to Sukna. 

 The distance along the road, from the place where the Damuda band 

 crosses it to the foot of the hills, is eight miles, and the difference of 

 level, as measured by aneroid, 1,800 feet. The distance in a straight line 

 is only three miles. If, subsequently, the out-turn should be sufficiently 

 large, it would of course be necessary to make more complete arrange- 

 ments, the plans which strike one as the simplest being either a tramway 

 along the side of the road or a direct wire-tramway. 



* Vol. Ill, pt, 1, p. 174. f Vol. Ill, pt. 1, p, 146. 



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