1-157-644 - Oxford Science Archive/Heritage Images

Davy's electric egg, 1883. Invented in 1809, it produced intense light from a voltaic arc between the points of two carbon rods. It was not until some years after Humphry Davy's (1778-1829) death that the carbon arc lamp was widely used because the rods need frequent adjustment. Davy used boxwood carbon. From Les Nouvelles Conquetes de la Science by Louis Figuier. (Paris, 1883).