John Buddle mining engineer. He succeeded his father as manager at Wallsend Colliery in 1806, though his work was not limited to just the local colliery. Buddle was involved with the introduction of the miners safety lamp invented by Humphry Davy being involved in the earliest discussions with Davy in August 1815 and providing "fire-damp" samples for experiments in Davy's London Laboratory. The moment when Buddle tested the new Davy safety lamp for the first time, for real, in Northeast England, is recorded by him in a report to the Select Committee on Accidents in Mines on 4 September 1835 "I first
Hefner lamp Hefner lamp The Hefner lamp, or in German Hefnerkerze, is a flame lamp used in photometry that burns amyl acetate. The lamp was invented by Friedrich von Hefner-Alteneck in 1884 and he proposed its use as a standard flame for photometric purposes with a luminous intensity unit of the Hefnerkerze (HK). The lamp was specified as having a 40 mm flame height and an 8 mm diameter wick. The Hefner lamp provided the German, Austrian, and Scandinavian standard for luminosity during the late nineteenth and early twentieth centuries. The unit of light intensity was defined as that produced by the