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Day in Engineering History Archive - April 23

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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.

April 23

Happy Birthday Max Planck! - Please click here to visit RF Cafe.

1858: Max Planck, who introduced quantum theory to the world, was born. 1896: The Vitascope system for projecting movies onto a screen, invented by Francis Jenkins and Thomas Armat, was demonstrated in New York City. 1915: The A.C.A. became the National Advisory Council on Aeronautics (NACA), which later became NASA. 1940: The Ray-o-Vac leak-proof flashlight battery was patented by Herman Anthony. 1955: Congress ordered all U.S. coins to bear motto "In God We Trust." 1960: Nobel Prize winner Max Von Laue, who discovered the diffraction of x-rays in crystals, died. 1968: The first decimal coins were distributed in Britain in preparation for replacing the current system of pounds, shillings and pence. 1985: Coca-Cola Co. announced it was changing the secret formula for Coke. 1994: The subatomic particle called the top quark was discovered at the DoE's Energy's Fermi National Accelerator Lab.


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