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To produce it, he drew on the ideas of others, as he often did, though he gave them no credit. After experimenting with any number of materials, he hit on carbon. He tried to give the impression that he came up with that idea independently. In fact, says Biographer Conot, his laboratory notebooks prove that he read and underlined reports of the experiments of Joseph Swan in England. Swan had invented an electric bulb that used a fine carbon rod.
There were technical differences between the bulbs that, Edison's partisans say, made his superior. For example, Swan's carbon rod was fairly thick, Edison's filament was thin. But a crucial difference was that Swan stopped with inventing the bulb, while Edison took what would now be called a "systems approach"; he saw that the bulb had to be only one of a whole series of inventions. To make it in the first place, he and his assistants had to produce a more complete vacuum than had ever been known before. Then they had to devise a power-distribution system for lighting the bulbs in millions of homes. In Edison's words: "There was no precedent for such a thing, and nowhere in the world could we purchase these parts. It was necessary to invent everything: dynamos, regulators, meters, switches, fuses, fixtures, underground conductors with their necessary connecting boxes, and a host of other detail parts, even down to insulating tape." They did, and on Sept. 4, 1882, Edison gave the order to throw the switch lighting up a small section of downtown Manhattan.
What drove him to invent? The desire to make money and win personal glory, of course. But even Edison saw that was not enough. One of his less noted sayings pointed the way not only for inventors but for all those who work with their brains. He plastered his labs with a quotation from Sir Joshua Reynolds: "There is no expedient to which a man will not resort to avoid the real labor of thinking," to which Edison added one of his own: "The man who doesn't make up his mind to cultivate the habit of thinking misses the greatest pleasures in life." A most unorthodox and in many ways unattractive thinker, Edison nonetheless multiplied the pleasures of life for everyone who listens to a record, watches a movie or flips a light switch.