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
Safety lamp of air. The Marsaut was one of the first lamps to be fitted with a shield, in the illustration (right) the bonnet can be seen surrounding the gauzes. A shielded Marsaut lamp can resist a current of 30 feet per second. The Bainbridge is a development of the Stephenson. A tapered glass cylinder surrounds the flame, and above that the body is a brass tube. The top of the tube is closed by a horizontal gauze attached to the body of the lamp by small bars to conduct heat away. Air enters through a series of small holes drilled in