Thursday, August 15, 2013
On Wireless Telegraphy and the Radio: Contrary to popular belief, Italian inventor Guglielmo Marconi did not invent the radio. He developed the wireless telegraph and brought it to the United States in 1899. It was a major upgrade from the standard telegraph because it allowed for the transmission of coded messages through the air. This proved especially important for ships at sea, which could now communicate over long distances and without the use of flags or lights. The wireless telegraph did not, however, allow for sounds (human voice, music, etc.) to be transmitted. That was precisely where the radio had a distinct advantage. But it would be another twenty years before advances in electronics technology could incite the growth of a full-fledged radio industry. Ultimately, what was needed for radio wave broadcasting were vacuum tubes (complex light bulbs). American inventor Lee de Forest had been experimenting with them in the early 1900s, having developed a triode ("The Audion") to amplify electronic signals. And in 1907, de Forest completed the world's first ship-to-shore radio broadcast while on a boat in Lake Erie. After which, he gloated, "I discovered an Invisible Empire of the Air, intangible, yet solid as granite."
Thursday, August 1, 2013
On General Electric and Irving Langmuir: When General Electric (GE) formed in 1892, Thomas Edison had already decided to abandon the electrification business and move on to motion pictures. He spent a majority of the 1880s installing direct current (DC) electrification systems for commercial buildings like J. P. Morgan's investment firm at 23 Wall Street. But his original 1879 patent for the incandescent light bulb was expiring, so GE sought to improve (and hopefully re-patent) it. To accomplish such a feat, GE established the nation's first corporate research and development (R&D) laboratory in 1901. The primary problem with Edison's light bulb lay in its carbon filament, which produced a blackened film around the inside of the bulb when lit. As a chemist who did part of his doctoral research on light bulbs, Irving Langmuir (pictured above) understood this problem well. GE hired him in 1909 to work in their R&D lab, and thus, Langmuir began experimenting with different filament materials to make the light bulb more efficient. He settled on tungsten because it has a very high melting point, and therefore, would not produce any unwanted by-products when lit for long periods of time. With Langmuir's tinkering, GE was able to re-patent the light bulb and avoid financial ruin.