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Emile Berliner emigrated from Germany to the United States in 1870 to avoid conscription, and while working odd jobs studied physics at night at New York's Cooper Union. He invented an improved telephone transmitter that Bell Telephone bought, then turned to sound recording, inventing the flat gramophone disc that displaced Edison's wax cylinder and became the standard format for recorded music for most of the twentieth century. He later spent two decades developing early helicopter technology, including a vertically mounted tail rotor to counteract engine torque, a configuration that anticipated the practical helicopter designs of the 1940s.