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
Edison and Swan Electric Light Company 1964, AEI merged its lamp and radio valve manufacturing interests with those of Thorn Electrical Industries to form British Lighting Industries Ltd. Edison Swan (or later Siemens Edison Swan) produced a wide range of vacuum tubes and cathode ray tubes under the names "Ediswan" or "Mazda" and the 1964 Mazda Valve Data Book claimed: "Professor Sir. Ambrose Fleming... was Technical Consultant to the Edison Swan Company at the time. It was this close co-operation between University and Factory which resulted in the first radio valve in the world." Edison and Swan Electric Light Company The Edison and Swan Electric Light