Kamm's Patent Kammatograph was invented ca.1898 by Leaonard "Leo" Ulrich Kamm. It was first offered for sale in 1900 by Leo's company, L. Kamm & Co. The company's factory and sales offices were located on Powell Street in London. The Kammatograph utilized dry glass plates rather than traditional film. My interest in the Kammatograph was piqued after researching another one of Leo's inventions, The Zerograph.