Day in Engineering History Archive - April 23

April 23

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." 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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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.