Why did flammable gases not ignite when coal miners used a Davy safety lamp?
The Davy lamp is a safety lamp devised in 1815 by Humphry Davy. It was created for use in coal mines, allowing deep seams to be mined despite the presence of methane and other flammable gases. Davy had discovered that, to explode, the gas must be heated to its ignition temperature and that if such heating is prevented combustion cannot occur. If the flame in a lamp is surrounded by metal gauze to distribute the heat over a large area, the maximum temperature of the screen is below the ignition temperature of the gas.
