Do you know what this is?
The flame safety lamp was invented by Sir Humphrey Davy in 1815. The lamp housed a flame within a cylinder of gauze that would dissipate the heat of the flame so it would not ignite any gas present. The lamp could then be used to check for the presence of methane gas or firedamp. If the flame burned high and with a blue tinge, then methane was present. If the flame grew low or went out, the miner would know that oxygen levels were low. Unfortunately the original lamps did not give out a lot of light and many miners would remove the gauze cylinder, heightening the risk of explosion.
In Australia the Davy flame safety lamp remained in use until 1986. An explosion at Moura No.4 mine, resulting in the deaths of 12 miners, led to an Inquiry and amendments to the Coal Mining Act, including the banning of flame safety lamps underground.