- Édouard Branly
Édouard Eugène Désiré Branly (
October 23 ,1844 -March 24 ,1940 ) was a Frenchinventor andphysicist . He was thephysics professor at the Catholic University of Paris. He is primarily known for his early involvement inwireless telegraphy and his invention of the Branlycoherer around 1890.The "coherer" was the first widely used detector for
radio communication. Branly built upon the discoveries ofTemistocle Calzecchi-Onesti , who demonstrated in experiments in 1884 through 1886 that iron filings contained in an insulating tube will conduct an electrical current under the action of an electromagnetic wave. The operation of the coherer is based upon the large resistance offered to the passage of electric current by loose metal filings, which decreases under the influence of radio frequencyalternating current . The coherer became the basis for radio reception, and remained in widespread use for about ten years. It was used by, amongst others,Guglielmo Marconi , in his early experiments.Oliver Joseph Lodge improved Edouard Branly's coherer as a detector of radio waves by adding a "trembler" which periodically dislodged clumped filings, thus restoring the device's sensitivity. The next innovation in radio wave detection, betweenNikola Tesla 's and Guglielmo Marconi's progress in radio in the 1890s and the 1948 invention of thetransistor , wasJohn Ambrose Fleming 'sFleming valve which replaced Branly's device for many uses.Branly was three times nominated for a Nobel prize, but he never received it. In 1911 he was elected to the
French Academy of Sciences . His rival wasMarie Curie . Both had opponents in the Academy: she was woman and he was a devout catholic, who left Sorbonne for a chair in the Catholic University of Paris. Finally, Branly won the election by two votes.Edouard Branly died in 1940 and was interred in the
Père Lachaise cemetery in Paris.The quai Branly - a road that runs alongside the River
Seine inParis - is named after Branly. It is the name of this road, not of Branly himself, that led to the naming of theMusée du quai Branly .ee also
*
Musée Edouard Branly , which preserves his laboratory
* "Radio ":History of radio ,Invention of radio
* "People":Alexander Stepanovich Popov ,Karl Ferdinand Braun
* "Other":List of people on stamps of France External links and resources
* Eugenii Katz, " [http://chem.ch.huji.ac.il/~eugeniik/history/branly.html Edouard Eugène Désiré Branly] ". The history of electrochemistry, electricity and electronics; Biosensors & Bioelectronics.
* " [http://www.newadvent.org/cathen/02740a.htm Edouard Branly] ". Robert Appleton Company, The Catholic Encyclopedia, Volume II, 1907.
* " [http://www.acmi.net.au/AIC/BRANLY_BIO.html Edouard Eugène Désiré Branly] "". Adventures in Cybersound.
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