Electric light by the first practical electric arc light in 1806. By the 1870s, Davy's arc lamp had been successfully commercialized, and was used to light many public spaces. The development of a steadily glowing filament suitable for interior lighting took longer, but by the early twentieth century inventors had successfully developed options, replacing the arc light with incandescents. The energy efficiency of electric lighting has increased radically since the first demonstration of arc lamps and the incandescent light bulb of the 19th century. Modern electric light sources come in a profusion of types and sizes adapted to many applications. Most modern
Fellow of the Royal Society of us shall signify to the President under our hands, that we desire to withdraw from the Society, we shall be free from this Obligation for the future". Since 2014, portraits of Fellows at the admissions ceremony have been published without copyright restrictions in Wikimedia Commons under a more permissive Creative Commons license which allows wider re-use. In addition to the main Fellowships of the Royal Society (FRS, ForMemRS & HonFRS), other fellowships are available which are applied for by individuals, rather than through election. Holders of these fellowships are known as Royal Society Research Fellows. In addition to the