Thomas Alva Edison was the most famous and prolific inventor of all time. During his life, over 1100 patents were issued to him or his associates; he was known as the wizard of Menlo Park, the town in New Jersey where he set up his first invention factory. Yet he was not really a scientist, having no theory or mathematics, and most of his success came from perfecting the ideas of others or already existing inventions by trial and error. He learned telegraphy on the railway, and his services as a telegrapher were in demand during the Civil War, when he traveled all over the country, incidentally studying electricity. In 1868 came his first invention: a machine to record votes in Congress. But Congress turned it down because they were not interested in speeding up matters. Edison then resolved to work only on inventions that were commercially viable.
             His first such invention was an improvement on the ticker machine which transmitted stock market prices. At this particular time in U.S. history, when Wall Street and big business were more powerful than the government and an enormous economic expansion was underway, this invention was so successful that Edison set up a small manufacturing plant to build ticker-tape machines, which he later sold at a profit. This was the first instance of Edison's ability to see what needed to be invented before inventing it. Next, he made improvements to the telegraph, culminating in a system that allowed four messages to be sent on one wire. He also made improvements to the typewriter.
             By 1876 Edison quit manufacturing and set up his first invention factory, with employees to help him develop ideas. Their first inventions were improvements to the telephone, including a microphone. At this moment Edison had invented the concept of commercial inventing, which has dominated twentieth-century technology.
             In 1877, Edison produced his most celebrated invention, certainly his own favorite: the phonograph...