Humphry Davy and the Murder Lamp
Max Adams investigates the truth behind the introduction of a key invention of the early Industrial Revolution.
The miners’ safety lamp is an icon of the Industrial Revolution every bit as powerful as Stephenson’s Rocket or the Iron Bridge at Coalbrookdale. It’s a beautiful thing: polished brass and glass cylinder, magnetic lock, and the little naphthalene flame lit by a flint and wheel. You can still buy one, because even today every pit deputy must carry one, despite the universal use of electricity for lighting collieries. The reason is that the safety lamp is first and foremost a methane detector; the colour and shape of the flame indicates how much methane or ‘fire-damp’ is present in the atmosphere. That some concentrations of firedamp are more deadly than others has been known since long before 1816 when Sir Humphry Davy developed the lamp that bears his name.
The truth is, though, that the lamp designed by Davy was a very different thing from today’s version. It had no glass for one thing; the flame shone weakly through a wire gauze; there was no lock, either, to prevent injudicious hands from opening it. Those of us brought up on the legend of the Davy lamp might also be surprised to learn that Davy was not the inventor of the safety lamp, and that his lamp was not really safe. In the decades after its invention deaths in mine explosions actually increased. Like the Industrial Revolution itself, the real history of the miners’ lamp is complex, quirky and surprising.