Geordie lamp

In 1815, Stephenson was the engine-wright at the Killingworth Colliery in Northumberland and had been experimenting for several years with candles close to firedamp emissions in the mine.

In August, he ordered an oil lamp, which was delivered on 21 October and tested by him in the mine in the presence of explosive gases.

He improved this over several weeks with the addition of capillary tubes at the base so that it gave more light, and tried new versions on 4 and 30 November.

Davy had originally attempted a safety lamp on similar principles, before preferring to enclose the flame inside a brass gauze cylinder; he had publicly identified the importance of allowing the restricted airflow in through small orifices (in which the flame velocity is lower) before Stephenson had, and he and his adherents remained convinced that Stephenson had not made this discovery independently.

[8] But this also posed the danger of breakage in the harsh conditions of mineworking, a problem which was not resolved until the invention of safety glass.

Stephenson's safety lamp shown with Davy's lamp on the left
Plate 1 and descriptive text for this, and plate 2, from page 32-33 of Report Upon the Claims of Mr. George Stephenson, Relative to the Invention of His Safety Lamp, by the Committee Appointed at a Meeting Holden in Newcastle November 1st 1817 [ 6 ]
George Stephenson's safety lamp as drawn in 1817.