William H McAdams was 20 years old when Thomas Edison demonstrates incandescent lighting to the public for the first time, in Menlo Park, New Jersey. Thomas Alva Edison was an American inventor and businessman, who has been described as America's greatest inventor. He developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and the long-lasting, practical electric light bulb. Dubbed "The Wizard of Menlo Park", he was one of the first inventors to apply the principles of mass production and large-scale teamwork to the process of invention, and is often credited with the creation of the first industrial research laboratory.
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