Screen Test: A fine-mesh kitchen sieve with a candle inside simulates a Davy miner’s safety lamp. An explosive mixture of propane gas and air is blown in from the outside. If the mesh is fine enough, the fire will stop at the screen even as the explosive gas flows through it. Mike Walker
If you were a coal miner in the early 1800s, the light you used was an open-flame oil lamp—even though mines were sometimes filled with “fire-damp,” a volatile mixture of air and methane gas. Explosions were inevitable, and at times threw bodies from mine shafts like grapeshot from a cannon. Humphry Davy became a national hero when, in 1815, he found a remedy: Surround the lamp flame with mosquito screen.