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Day in Engineering History Archive - December 13

| Jan | Feb | Mar | Apr | May | Jun |
| Jul | Aug | Sep | Oct | Nov | Dec |

Note: These historical tidbits have been collected from various sources, mostly on the Internet. As detailed in this article, there is a lot of wrong information that is repeated hundreds of times because most websites do not validate with authoritative sources. On RF Cafe, events with hyperlinks have been verified.
Please submit significant historical events and dates for inclusion in these lists. I will be glad to include your name and birthday. Please do not submit your death date ;-)
A couple years ago, I began commemorating the birthdays of notable people and events with special RF Cafe logos. Where available, I like to use images from postage stamps from the country where the person or event occurred.

December 13

Happy Birthday Ernst Werner von Siemens.  Please click here to visit RF Cafe.

1545: Council of Trent began. 1816: Werner von Siemens, German electrical engineer who helped develop telegraph industry (and for whom the unit of conductance is named after), was born. 1903: Wright Brothers made their first flight at Kittyhawk, NC. 1920: first accurate measurement of the size of a fixed star was made on Betelgeuse and was found to be 260 million miles in diameter - 150 times larger than the previous measurement. 1934: Thomas Watson, assistant to Alexander Graham Bell, died. 1939: Perkin Elmer incorporated. 1940: French biophysicist Jacques-Arsène d' Arsonval, who invented the reflecting moving-coil galvanometers used to measure weak electric currents, died. 1962: The first U.S. communications earth satellite to transmit telephone, television, teleprinter & facsimile signals, Relay I, was launched. 1990: Tim Berners-Lee launched the World Wide Web. 1994: First meeting of the World Wide Web (W3) Consortium took place in Cambridge at the Massachusetts Institute of Technology.


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