Catalogue Page from Exhibition Catalogue: 1911 Fifty-sixth Annual Exhibition of the Royal Photographic Society of Great Britain

showing (E11A067) Exhibit no. [971]: New Metal-Filament Lamp for Portrait Work or night work for copying, Naturalists, etc. Very short exposures with small number of lamps. High efficiency 8 watts per candle power. by Sanger-Shepherd & Co., Ltd. ()