Safety lamp, Stephenson, by George Knight & Son, London, marking: makers name, 1839-1857.

George Stephenson's experiments were carried out in 1815, simultaneously with those of Sir Humphrey Davy, with oil lamps to which air was supplied through small tubes, the flame being enclosed by a glass chimney to create a draught. A case of perforated copper, subsequently of wire gauze, was added to protect the chimney. In the final form shown, known as the " Geordie," air is admitted through fine holes in the bottom ring of the cage and passes through the gauze and under the internal glass chimney to the flame; this chimney is surmounted by a perforated copper cap; these parts are assembled by a following -up ring, the method still most used. The reservoir is filled from an external spout. A screw lock is fitted.

The "Geordie" was considered to be safer than the " Davy," but required more careful cleaning.