Thomas Edison’s name is synonymous with invention, and his most famous invention, the electric light bulb, is a familiar symbol for that flash of inspired genius traditionally associated with the inventive act. besides being the exemplar of the “bright idea,” however, Edison’s electric light is worthy of study for other reasons. The technical and economic importance of the light and of the electrical system that surrounded it matches that of any other invention we could name, at least from the last two hundred years. The introduction and spread of electric light and power was one of the key steps in the transformation of the world from an industrial age, characterized by iron and coal and steam, to a postindustrial one, in which electricity was joined by petroleum, light metals and alloys, and internal combustion engines to give the twentieth century its distinctive form and character. our own time still largely carries the stamp of this age, however dazzled we may be by the electronic, computerized, and media wonders of the twentyfirst century.
[...]... kinds of calculations He calculated the power of the instrument and of the lights, the probable loss of power in transmission, the amount of coal the instrument would save in a day, a week, a month, a year, and the result of such saving on manufacturing.5 The optimistic (or naïve) Sun reporter then went on to describe the possibilities of harnessing Niagara Falls and distributing the resulting electric. .. solved the problem of the electric light The central technical feature of his solution was the principle of the self-regulating element The key to a successful light, Edison believed, was the devising of a reliable mechanism to maintain a balance between the power needed to make the lamp element (entirely or largely of platinum) incandescent and the power that would cause the element to melt or otherwise... on electric lighting, “Caveat for Electric Light Spirals.” (A caveat provides preliminary protection for an invention prior to filing a patent application.) Therein he wrote: The object of this invention is to produce light for illuminating purposes by metals heated to incandescence by the passage of an electrical current through them, a great number of pieces of such metals forming part of an electric. .. light and its various forms of regulators, but also of a growing awareness of the need to develop other components of an electric lighting system The most crucial of these was the generator It is important to remember that the experiments begun in the fall of 1878 marked Edison’s first real encounter with the production of electric current by mechanical means All his previous electrical work—with telegraphs,... examine the state of the art in electric lighting 18 edison’s electric light and went on to ask if Moses Farmer would not be a good expert for the job.33 Edison himself asked his patent attorney for a list of all U.S patents on the electric light. 34 He also suggested to the Light Company directors that Howard R Butler of the Gold & Stock Telegraph Company be hired to make a thorough search of the patent... 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 2 edison’s electric light 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... own temperature.” Most of these devices used the expansion of metal—either the incandescent spiral itself or another piece of metal nearby—to trigger an interruption or reduction of current when the fusing point of the incandescent metal was 8 edison’s electric light approached The combinations of electromagnets, switches, resistance elements, and levers were clearly products of the telegraphic technology... weeks, at the end of the summer of 1878, he saw the problem of the electric light as electromechanical, and no one in the world had more self-assurance that he could solve problems of this kind than Edison And, indeed, the world at large shared this confidence The problem of subdividing the light was, after all, a well-known oft-attacked challenge, one that had already stumped some very good electrical... for domestic lighting, where the desired light intensity was of the order of 10 to 20 candlepower (the range of a gas light) rather than the thousands characteristic of the arc Whereas the arc light was beginning to find some applications in 1878, lighting by incandescence was far from being a practical technology Davy had shown that an electric current could be used to heat a material to the point where... all in the beginning Edison did make the point that his electric light would operate in just the fashion of the gaslight, but this was more boast than model And the image that was sometimes drawn of Niagara supplying all of America with light was clearly more dream than plan As the fall of 1878 wore on, the spirit behind the work at Menlo Park changed The serious difficulties encountered in the design . domestic lighting, where the desired light intensity was of the order of 10 to 20 candlepower (the range of a gas light) rather than the thousands characteristic of the arc. Whereas the arc light. with the simplicity of a child, and made all kinds of calculations. He calculated the power of the instrument and of the lights, the probable loss of power in transmission, the amount of coal. with the inven- tive act. Besides being the exemplar of the “bright idea,” however, Edison’s electric light is worthy of study for other reasons. The tech- nical and economic importance of the light