It is worthy of remark that, under circumstances in which the wire-gauze of the Davy lamp becomes red-hot from the high explosiveness of the gas, the Geordy lamp is extinguished; and we can not but think that this fact testifies to the decidedly superior safety of the Geordy. An accident occurred in the Oaks Colliery Pit at Barnsley on the 20th of August, 1857, which strikingly exemplified the respective qualities of the lamps. A sudden outburst of gas took place from the floor of the mine along a distance of fifty yards. Fortunately, 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. On this occasion, the whole of the Stephenson 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 that several of the men using them had their hands burnt 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 Geordy, which is immediately extinguished as soon as the air becomes explosive.[49] Nicholas Wood, a good judge, has said of the two inventions, "Priority has been claimed for each of them--I believe the inventions to be parallel. By different roads they both arrived at the same result. Stephenson's is the superior lamp. Davy's is safe--Stephenson's is safer." When the question of priority was under discussion at Mr. Lough's studio in 1857, Sir Matthew White Ridley asked Robert Stephenson, who was present, for his opinion on the subject. His answer was, "I am not exactly the person to give an unbiased opinion; but, as you ask me frankly, I will as frankly say, that if George Stephenson had never lived, Sir Humphry Davy could and most probably would have invented the safety-lamp; but again, if Sir Humphry Davy had never lived, George Stephenson certainly would have invented the safety-lamp, as I believe he did, independently of all that Sir Humphry Davy had done in the matter." To this day the Geordy lamp continues in regular use in the Killingworth Collieries, and the Killingworth pitmen have expressed to the writer their decided preference for it compared with the Davy. It is certainly a strong testimony in its favor that no accident is known to have arisen from its use since it was generally introduced into the Killingworth pits. [Illustration: THE STEPHENSON TANKARD.] FOOTNOTES: [43] Evidence given by George Stephenson before the Select Committee on Accidents in Mines, 26th June, 1835.