Edison and the age of invention

Like many other electrical inventors of his day, Thomas A. Edison began his career in the telegraph office. Edison’s telegraph inventions generated enough income to permit him to become an independent inventor and to build a research-and-development laboratory at Menlo Park, New Jersey, in 1876. Despite the commercial failure of harmonic telegraphs, the telephone arose out of this work. While the world remembers Alexander Graham Bell as the inventor of the telephone, his design was of limited practical value. Edison’s transmitter made the telephone a technical and commercial success. One consequence of Edison’s work on the telephone was his invention of the phonograph, the first device to record and reproduce sound. On September 16, 1878, Edison announced a new and ambitious line of research and development - electric power and lighting. Edison’s development of motion pictures demonstrated what a modern research-and-development laboratory could accomplish.