SCIENCE PHOTO LIBRARY SCIENCE PHOTO LIBRARY
Thomas Edison. Coloured portrait of Thomas Alva Edison (1847-1931), American inventor. Despite a lack of formal training, Edison was a prolific inventor, patenting about 1300 innovations. These included the phonograph, the electric light bulb and the alkaline battery. He solved problems by sheer weight of effort, claiming that "Genius is one percent inspiration and ninety-nine percent perspiration". He made only one scientific discovery, the Edison Effect. This applies in vacuum tubes, where electricity will flow from a hot electrode to a cool one, but will not do the reverse. This idea formed the basis of thermionic valves.
Model release not available. Property release not required.