Edison's first contracts for inventions were with the Gold and Stock Telegraph Company in New York City. With the money he received from these invention contracts, he operated a few telegraph manufacturing shops in Newark in the early 1870s. While operating these businesses, he became embroiled in a patent battle over one of his inventions, the quadruplex telegraph. When the battle was settled, he received a new contract with Western Union. He used this capital to establish a research laboratory in Menlo Park, New Jersey, in 1876.At the Menlo Park facility, Edison developed many important inventions. He improved upon Alexander Graham Bell's telephone (1877–8) and was embroiled in a number of court battles over the invention. (Bell was the victor of these battles.) He also invented the phonograph there. The device was patented on February 19, 1878. His most famous
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