“I hereby certify that I have this day tried Messrs. Upton and Roberts’ new patent safety lamp, in the Jarrow colliery; and I state, as an experienced pitman, having been thirty-two years master wasteman in that colliery, that I greatly prefer this new lamp to the common Davy lamp. I had it between five and six hours on trial in the pit. I consider that it gives about three times the light of the Davy lamp, as I could see at least ten yards before me in a straight line; and of its great safety I can have no doubt, as it does not fill with flame, as the Davy does. And although I had this extra light, there was much less oil consumed. I consider it a good working lamp.
“Jarrow Colliery, near Newcastle on Tyne, March 31, 1836.” (Signed) “ROBERT FAIRLY.”
[Fig. 953.], is a vertical section through the middle of the lamp. a, a, is the oil-cistern, showing the fold of the wick; it is covered at top with b, b, several layers of wire gauze; c, c, is the perforated brass ring, under these layers, for admitting air, which is reverberated upon the burning wick by the cupola c; d, d, is the cylinder of glass, surrounding the wire-cloth one; e, e, is the safety brass hood, which screws down in the frame, so as to cover in the top of the glass chimney; f, is the arched wire for suspending the lamp to the girdle of the miner; g, is the bent tube for supplying oil to the cistern; and h is the safety-trimmer, shown more distinctly in the figure illustrative of the [Lamp of Davy].
Between the glass and the cage there should be a space of about one-tenth of an inch, forming an annular chimney for the free ventilation of the flame; and between the under edge of the hood e, and the upper rim of the glass, there should likewise be an interval, as also vent-holes in the top of the hood, for the free escape of the smoke. The orifice of the little tube g, should be rather lower than the ring of holes c, otherwise the oil, when incautiously poured into it, might overflow them, and prevent the lamp from burning. The figure is drawn somewhat in perspective.
As the naked cage of Davy often gets red-hot with flame; as it is sometimes used for hours by miners in this most hazardous state; as this lamp gives so little light as to tempt rash men to remove its safety-cage;[50] as “it is upon record, that taking the average of ten years previous to the introduction of Sir H. Davy’s safety lamp, and allowing one clear year for its introduction, and of ten years after it was properly introduced, there had been double the number of accidents, and at least double the number of deaths, of what took place in the ten years previous to its introduction;[51] as his lamp in explosive air-courses needs to be carried close upon the bosom, or under the coat of the miner; as it was declared by its illustrious inventor to be dangerous when exposed to such currents of explosive gas; and as the above described modification of it is free from all these defects and dangers,—I humbly apprehend that no conscientious proprietor or viewer of coal-mines will delay to substitute the lamp of Upton and Roberts for the naked Davy, for otherwise he will certainly stand in a very painful predicament before a coroner’s inquest, at the next mortal casualty from explosion.”
[50] At Rowpit Harraton, June 30, 1817, thirty-eight lives were lost by the wilfulness of one man unscrewing it, though he was well forewarned of the danger. He said, “he could not see with that thing,” meaning the Davy.—Buddle, in Report of House of Commons, p. 215.
[51] Dr. Reid Clanny, in Report on Accidents in Mines, p. 32. I observe that in Sykes’ Local Records of the counties of Durham and Northumberland, corrected by J. Buddle, Esq., there are 540 deaths by explosions, between June, 1817, and June, 1835. What a mass of misery to the families of the sufferers!
The patentees have, I am told, been put to so much trouble and expense in trying to introduce this life-protector into our coal-mines, that they have in a great measure abandoned the business. Messrs. Smith of Birmingham have meanwhile undertaken to make the lamps.