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Day in Engineering History Archive February 21

| 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.

February 21



1842: John Greenough patented the sewing machine. 1865: John Deere received a patent for his plow. 1878: The first U.S. telephone directory of about 50 names was issued by the New Haven Telephone Company, in CT. 1926: Dutch physicist Heike Kamerlingh Onnes, who discovered superconductivity, died. 1937: The Arrowbile, the first convertible automobile-airplane, made its maiden flight. 1938: George Hale, responsible for the 200-inch telescope bearing his name on Palomar Mountain, died. 1947: Edwin Land publicly demonstrated his Polaroid Land camera, which could produce a black-and-white photograph in 60 seconds. 1958: The U.S. submarine Gudgeon (SS 567) completed 228 days of circumnavigating the world. 1995: Chicago stockbroker Steve Fossett became the first person to fly solo across the Pacific Ocean in a balloon, landing in Leader, Saskatchewan, Canada.
 

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