A 'bonnetted' Clanny lamp, no 19, c 1882.
© Science Museum / Science & Society Picture Library
The 'bonnetted' Clanny is an updated version from the Royal Commision on Accidents in Mines (1879-1886) of the original Clanny lamp. This safety lamp, designed by Dr William Reid Clanny (1776-1850), reduced the risk of explosions caused by 'firedamp', a gas composed mainly of methane which is found in deep mines. It is made of nickel and silver and has a dioptric lens. The air for supplying the flame comes in through the bottom of the gauze and pases down the inner side of the glas, protecting it from overheating. The disadvantages of this lamp were that a lot of light was lost by absorption in the glas, and it was heavier and more expensive than the Davy lamp. Safety lamps started to be replaced with electric mine lighting devices after 1900.