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Day in Engineering History Archive - December 9

| 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 9

Happy Birthday Grace Hopper!  Please click here to visit RF Cafe.

1879: The first U.S. patent was issued for an automatic telephone switching system. 1886: Clarence Birdseye, inventor of deep freezing food, was born. 1906: Navy Rear Admiral Grace Murray Hopper, credited with coining the term "bug" in computers, was born. 1914: The Edison Phonograph Works was destroyed by fire. 1921: American electrical engineer Charles Kettering first tested tetraethyl lead as an anti-knock additive to gasoline fuel. 1968: The first demonstration of the use of a computer mouse was given by its inventor, Doug Engelbart. 1993: At Princeton University in New Jersey, scientist produced a controlled fusion reaction equivalent to 3 MW. 1993: Shuttle astronauts inserted a corrective lens in the Hubble Space Telescope to fix its optical flaw.


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