Edison's Electric Light: The Art of Invention

1. “A Big Bonanza”

1 chapter one “A Big Bonanza” In 1878, Thomas Edison was only 31 years old, but he had already produced enough significant inventions to credit a lifetime. The press recognized this achievement by calling him the “Wizard of Menlo Park.” Beginning with his improved stock ticker of 1869, his contributions to telegraphy alone were enough to establish him as perhaps the premier electrical inventor of his day. Not only were his systems of automatic and multiplex telegraphy technical marvels , but their possible economic significance made Edison’s name as familiar to the financiers of Wall Street as it was to the followers of the technical and scientific press. Successful dealings with the telegraph empire builders of New York had given Edison the means to construct his unique laboratory in the New Jersey countryside. And there at Menlo Park, he and a group of loyal co-workers operated a true “invention factory.” Soon after the lab was completed in the spring of 1876, Edison and his team moved beyond telegraphy. Their first important successes were in the field of telephony. Edison’s carbon transmitter of 1877 was a crucial element in turning the experimental devices of Alexander Graham Bell and Elisha Gray into practical instruments for communication. The broad range of approaches Edison used in his inventive efforts sometimes yielded surprising results, as when in late 1877 experiments on repeating and recording devices for use with telephones resulted in the phonograph. The “talking machine” was surely Edison’s most surprising invention. Despite the primitive quality of his tinfoil cylinder device, the public was agog at the machine. Most of the first months of 1878 were taken by travel and 2 edison’s electric light demonstrations in response to the public clamor for showings of the phonograph. The “Wizard” became the object of enormous press attention, for hardly anything would seem to be beyond the capability of a man who could invent a machine that talked. Indeed, when New York’s somewhat flamboyant Daily Graphic ran an April Fool’s Day story headlined “A Food Creator: Edison Invents a Machine That Will Feed the Human Race,” other newspapers repeated it as straight news.1 For the first half of 1878 Edison basked in the spotlight. The surprise of the phonograph, along with the enthusiasm it generated from the public, turned his inventive energies away from their normally doggedly practical direction. He produced devices like the “aurophone” and the “telescopophone,” both not very useful amplifying instruments. His observation of the changing resistivity of carbon under varying pressure led to the invention of the “tasimeter ,” intended as a supersensitive heat measuring device. All of Second Floor of the Menlo Park Laboratory, 1878. This photograph shows some of the apparatus on the second floor of Edison’s Menlo Park laboratory that made this the best-equipped private laboratory in the United States. “A Big Bonanza” 3 these efforts were in part simply ways of showing off his inventive virtuosity, as well as a reaction to the lesson of the phonograph that even the most unlikely avenues of experimentation may yield wonderful discoveries. The financial needs of the laboratory and its workers assured the continuance of more practical efforts. Much time and energy were devoted during these months to the further development of telephone components. The jumble of patents and conflicting business interests surrounding the technology of the telephone gave Edison and his backers the incentive to develop telephone devices that would complement the carbon transmitter and yet avoid the patents of Bell and others on receiving equipment. Later in 1878, the Menlo Park efforts would yield the chalk-drum telephone receiver , a clever device that was in many ways an improvement over other instruments but that turned out to be impractical in broad application. Despite its obvious potential for lucrative profits and its technical similarity with telegraphy, the telephone already represented a crowded field, one that no longer held out the promise of quick breakthroughs. It should be no surprise, therefore, that in the middle of 1878 Edison was seeking fresher directions for his endeavors. Edison’s biographers describe his condition in the late spring of 1878 as “very tired and ill.”2 The never-ending round of public appearances to demonstrate the phonograph, claims and counterclaims surrounding his telephone inventions, and the constant grind of the lab had worn him down to the point where his need for a vacation was apparent...