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Day in Engineering History Archive - April 25

Day in Engineering History April 25 Archive - RF CafeHappy Birthday to Guglielmo Marconi!  Please click here to visit RF Cafe.April 25

1744: Swedish astronomer Anders Celsius, after whom the temperature scale is named, died. 1792: The guillotine was first used in France to execute highwayman Nicolas J. Pelletier. 1840: Siméon-Denis Poisson, mathematician and experimenter in electromagnetic theory, died. 1849: Felix Klein, mathematician and creator of the single-surfaced Klein bottle, was born. 1859: Ground was broken for the Suez Canal. 1874: Radio pioneer Guglielmo Marconi was born in Bologna, Italy. 1900: Austrian-Swiss Nobel physicist Wolfgang Pauli, of Exclusion Principal fame, was born. 1901: New York became the first state to require automobile license plates - the fee was $1. 1927: Dudley Allen Buck, inventor of the cryotron switch and ferroelectric RAM, was born. 1928: Floyd Bennett, who piloted the airplane that flew Admiral Byrd, died. 1953: Dr. James D. Watson and Dr. Francis H.C. Crick suggested the double helix structure of DNA. 1961: Robert Noyce was granted a patent for the integrated circuit. 1990: The Hubble Space Telescope was deployed.

| 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. Many 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. Images used in the logos are often from open source websites like Wikipedia, and are specifically credited with a hyperlink back to the source where possible. Fair Use laws permit small samples of copyrighted content.

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