Safety lamp could create a sufficient updraft that firedamp would not penetrate down the chimney. Further observations of the speed of flame fronts in fissures and passageways led him to design a lamp with fine tubes admitting the air. Sir Humphry Davy was asked to consider the problems of a safety lamp following the Felling explosion. Previous experimenters had used coal gas (chiefly carbon monoxide) incorrectly, believing it to be the same as firedamp. Davy however performed his experiments with samples of firedamp collected from pits. As an experimental chemist, he was familiar with flames not passing through gauze; his experiments enabled
Carcel lamp were that the movement operated unattended, the oil could be used to the last drop, the lamp would stay lit for sixteen hours continuously without refilling, and it provided illumination for several persons at the same time with a single burner. They were more complex devices however, and were more expensive and prone to problems in the mechanism. They were most popular in wealthier European cities. Their unpopularity was partially due to the necessity of having to return them to the (mostly European) manufacturers for repair. In 1829 the simpler Moderator lamp was invented, which dispensed with clockwork and used