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Day in Engineering History Archive - July 4

July 4

Happy 4th of July - Independence Day!  Please click here to visit RF Cafe.Today is Independence Day! 1753: Jean-Pierre-François Blanchard, who was the first to fly across the English Channel (in a balloon), was born. 1776: The amended Declaration of Independence, prepared by Thomas Jefferson, was approved and signed by John Hancock, President of the Continental Congress in America. 1817: Construction started on the Erie Canal. 1868: Astronomer Henrietta Swan Leavitt, who discovered the relationship between period and luminosity in Cepheid variables, was born. 1883: The first 3-wire central-station incandescent-lighting plant, built by the Edison Electric Illuminating Co., started operations in Sunbury, PA. 1883: Rube Goldberg, engineer famous for his drawings of Mouse Trap-like contraptions, was born. 1903: President Theodore Roosevelt sent the first official message over the new cable across the Pacific Ocean between Honolulu, Guam, Midway and Manila. 1906: Vincent Schaefer, who invented cloud seeding for making rain, was born. 1922: Lothar von Richthofen, WWI flying ace and brother of the Red Baron, died. 1933: William Coolidge obtained a patent for the X-ray tube. 1934: Chemist Marie Marja Sklodowska Curie, discoverer of radium and polonium, died. 1960: The 50-star U.S. flag made its debut in Philadelphia, PA. 1976: Israeli commandos rescued the Entebbe Airport hostages held by Arab terrorists. 1997: The Mars Pathfinder, an unmanned space vehicle, landed on the Martian surface.

| 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.

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