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
Döbereiner's lamp said that in 1820s over a million of the "tinderboxes" were sold. Examples of the lighter are exhibited in the Deutsches Museum and in the old pharmacy at Heidelberg Castle. Döbereiner's lamp Döbereiner's lamp, also called a "tinderbox" ("Feuerzeug"), is a lighter invented in 1823 by the German chemist Johann Wolfgang Döbereiner; the lighter is based on the Fürstenberger lighter and was in production until ca. 1880. In the jar, similar to the Kipp's apparatus, zinc metal reacts with dilute sulfuric acid to produce hydrogen gas. When a valve is opened, a jet of hydrogen is released onto a platinum