Day in Engineering History Archive - April 9

April 9

1770: Thomas Seebeck, who discovered that an electric current flows between different conductive materials that are kept at different temperatures (Seebeck Effect), was born. 1864: Sebastian de Ferranti, an electrical engineer who developed the first 10 kV (4x previous) transmission system and components, was born. 1865: Robert E. Lee surrendered to Ulysses S. Grant at Appomattox Courthouse in VA. 1895: Astronomer James Keeler proved the rings of Saturn were composed of meteoric particles. 1899: James McDonnell, founder of the McDonnell Aircraft Corporation, was born. 1934: Oskar von Miller, who pioneered the electric power industry in Germany, died. 1940: Germany invaded Denmark and Norway. 1953: Man in the Dark, the first 3D motion picture produced and released by a major company, was shown. 1959: NASA announced the selection of America's first seven astronauts: Scott Carpenter, Gordon Cooper, John Glenn, Gus Grissom, Wally Schirra, Alan Shepard and Donald Slayton. 1963: Winston Churchill becomes first honorary U.S. citizen. 1965: "TIME" magazine featured a cover with the entire "Peanuts" gang. 1967: The first Boeing 737 made its maiden flight. 2003: Newly liberated Iraqi citizens toppled a statue of Saddam Hussein in Baghdad.

| 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.