Thomas Alva Edison was born in 1847 in Milan, Ohio. During his early career as a telegraph operator, Edison was continuously experimenting with telegraphic methods. His first significant invention was the art of duplexing - sending two signals on the same line. With the proceeds from his first sale Edison set up a workshop for invention in Menlo Park, New Jersey. Edison numerous other inventions included the automatic telegraphic repeater, the printing telegraph, the phonograph, the electric lamp and the alkaline battery. Towards the end of his life he also produced talking movies.