CHAP. VII. 



MERITS OF THE GEOKDY LAMP. 



127 



tunately the men working in the pit at the time 

 were all supplied with safety-lamps the hewers with 

 Stephenson's, and the hurriers with Davy's. Upon this 

 occasion, the whole of the Stephenson's lamps, over a 

 space of five hundred yards, were extinguished almost 

 instantaneously ; whereas the Davy lamps were filled 

 with fire, and became red-hot so much so, that several 

 of the men using them had their hands burned by the 

 gauze. Had a strong current of air been blowing 

 through the gallery at the time, an explosion would most 

 probably have taken place an accident which, it will 

 be observed, ^could not, under such circumstances, occur 

 from the use of the Greordy, which is immediately extin- 

 guished as soon as the air becomes explosive. 1 



1 The accident above referred to 

 was described in the ' Bamsley Times,' 

 a copy of which, containing the ac- 

 count, Robert Stephenson forwarded 

 to the author, with the observation 

 that "it is evidently written by a 

 practical miner, and is, I think, worthy 

 of record in my father's Life." The 

 superiority of the Stephenson lamp 

 has since formed the subject of a 

 lengthy communication which ap- 

 peared in the ' Times ' of December 

 24th, 1860, signed John Brown, C.E., 

 of Bamsley, an able milling engineer, 

 in reply to a previous communication 

 urging the sufficiency of ventilation 

 for keeping mines clear of explosive 

 gas. 



" I am well acquainted with col- 

 lieries," says Mr. Brown, "that are 

 liable to yield, without a moment's 

 warning, such large quantities of ex- 

 plosive gas that I am quite sure no 

 amount of ventilation that can practi- 

 cally, and not upon paper, be passed 

 through the workings, would dilute 

 the enormous quantities of this sud- 

 denly issuing gas sufficiently to pre- 

 vent it igniting at the first naked 

 light with which it came in contact. 



" I have known in this district gas 

 to issue from beneath the coal with 

 such violence as to rip up the floor, 

 which was almost as hard as stone, 

 producing great fissures several feet in 



depth and many yards in length, the 

 gas issuing therefrom with a noise like 

 that produced by high-pressure steam 

 escaping from a safety-valve. 



"At the period of this occurrence 

 we had two kinds of safety-lamps in 

 use in this pit viz., 'Davy' and* 

 ' Stephenson,' and the gas in going off 

 to the upcast shaft had to pass great 

 numbers of men, who were at work 

 with both kinds of lamps, The whole 

 of the ' Davy's ' became red-hot al- 

 most instantaneously from the rapid 

 ignition of the gas within the gauze ; 

 the 'Stephenson's' were as instantly 

 self-extinguished from the same cause, 

 it being the prominent qualification of 

 these lamps that, in adddition to 

 affording a somewhat better light than 

 the ' Davy ' lamp, they are suddenly 

 extinguished when placed within a 

 highly explosive atmosphere, so that 

 no person can remain working and run 

 the risk of his lamp becoming red-hot 

 which, under such circumstances, 

 would be the result with the ' Davy ' 

 lamp. 



" The red-hot lamps were, most 

 fortunately, all safely put out, al- 

 though the men in many cases had 

 | their hands severely burned by the 

 gauze; but from that time I fully 

 resolved to adopt the exclusive use of 

 the ' Stephenson ' lamps, and not ex- 

 pose men to the fearful risk they must 



