Gas detector early detection methods relied on less precise detectors. Through the 19th and early 20th centuries, coal miners would bring canaries down to the tunnels with them as an early detection system against life-threatening gases such as carbon dioxide, carbon monoxide and methane. The canary, normally a very songful bird, would stop singing and eventually die if not removed from these gases, signaling the miners to exit the mine quickly. The first gas detector in the industrial age was the "flame safety lamp" (or Davy lamp) was invented by Sir Humphry Davy (of England) in 1815 to detect the presence of
Lewis lamp Lewis lamp The Lewis lamp is a type of light fixture used in lighthouses. It was invented by Winslow Lewis who patented the design in 1810. The primary marketing point of the Lewis lamp was that it used less than half the oil of the prior oil lamps they replaced. The lamp used a similar design to an Argand lamp, adding a parabolic reflector behind the lamp and a magnifying lens made from green bottle glass in front of the lamp. A similar variant using a parabolic reflector was created by the inventor of the Argand lamp, Aimé Argand. While