Safety lamp, Ashworth-Hepplewhite Gray, Gray type, Stoke's alcohol tester, use: gas testing, maker: J. Davis and Son, Derby, marking: Stokes patent gas tester, 1901

This is an Ashworth Hepplewhite Gray lamp for fire-triers' use. improved by the addition of a screwed plug in the bottom, in place of which may be inserted an alcohol lamp as patented in 1893 by Mr. A. H. Stokes, H.M. Inspector of Mines. The spring cap, covering the hole through which the wick tube of the alcohol lamp is inserted, is forced aside as the latter is screwed in; the wick is lit from the oil flame, which is then extinguished. The capacity is 120 tests, occupying about 2 min. each, such tests being only intended to be made when an examination with the oil flame fails to detect gas. A screw lock is fitted.