The Chesneau lamp was designed in 1892 by M. Chesneau, the president of the French Fire Damp Commission. The Chesneau is a flame safety lamp fuelled by wood alcohol and designed specifically to detect firedamp.
The lamp has a graduated scale attached to its 'bonnet' that is used to measure the height of the lamp's flame through its mica window. The growth in flame height, and the colour of the flame, indicated to the miner the quantity of firedamp in the surrounding air.
The flame safety lamp was successful in improving the safety of mineworkers in the potentially dangerous atmosphere that existed underground. Flame safety lamps, although remaining in use as gas detectors, began to be replaced by safer and brighter electric lamps at the beginning of the 20th century.