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
Safety lamp firedamp). A boy (Thomas Elliott) was employed to carry hot lamps to the fresh air and bring cool lamps back. For some reason he stumbled; the gauze was damaged and the damaged lamp triggered the explosion. At Trimdon Grange (1882) a roof fall caused a sudden blast of air and the flame passed through the gauze with fatal results (69 killed). Poor copies and ill-advised "improvements" were known, but changing dimensions either reduced the illumination or the safety. The poor light compared to either the Geordie or Clanny eventually led to the Davy being regarded as "not a lamp but