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Radio Invention
James Clerk Maxwell predicted the propagation of electromagnetic waves (radio waves) (1873) and Heinrich Rudolf Hertz made the first demonstration of transmission of radio waves through free space (1887) but many individuals—inventors, engineers, developers and businessmen constructed systems based on their own understanding of these and other phenomenon, some predating Maxwell and Hertz' discoveries. Thus "wireless telegraphy" and radio wave based systems can be attributed to multiple "invento -
Telephone Invention
The first successful telephone transmission of clear speech using a liquid transmitter when Bell spoke into his device, “Mr. Watson, come here, I want to see you.” and Watson heard each word distinctly. -
Car Invention
In 1879, Benz was granted a patent for his first engine, which had been designed in 1878. Many of his other inventions made the use of the internal combustion engine feasible for powering a vehicle. His first Motorwagen was built in 1885 in Mannheim, Germany. He was awarded the patent for its invention as of his application on 29 January 1886. -
19th amendment
The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any state on account of sex. Congress shall have power to enforce this article by appropriate legislation. http://www.law.cornell.edu/constitution/amendmentxix Ratified August 18th 1920 -
18th amendment
After one year from the ratification of this article the manufacture, sale, or transportation of intoxicating liquors within, the importation thereof into, or the exportation thereof from the United States and all territory subject to the jurisdiction thereof for beverage purposes is hereby prohibited http://www.albany.edu/~wm731882/18th_amendment_final.html -
Emergency Quota Act
The objective of this act was to temporarily limit the numbers of immigrants to the United States by imposing quotas based on country of birth. Annual allowable quotas for each country of origin were calculated at 3 percent of the total number of foreign-born persons from that country recorded in the 1910 United States Census. http://library.uwb.edu/guides/usimmigration/1921_emergency_quota_law.html -
Immigration Act
The 1924 Immigration Act set quotas that limited annual immigration from particular countries. The legislation identified who could enter as a "non-quota" immigrant; this category included wives and unmarried children of US citizens, residents of the Western hemisphere, religious or academic professionals, and “bona-fide students” under 15 years of age. http://library.uwb.edu/guides/usimmigration/1924_immigration_act.html -
Television Invention
On March 25, 1925, Scottish inventor John Logie Baird gave the first public demonstration of televised silhouette images in motion, at Selfridge's Department Store in London. -
Black Thursday
On this date, a then-record number of shares were traded on the New York Stock Exchange by panicked investors, marking the onset of the stock market crash that precipitated the Great Depression. -
Black tuesday
On this date, share prices on the New York Stock Exchange completely collapsed, becoming a pivotal factor in the emergence of the Great Depression. -
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Hoover Dam
Hoover Dam, once known as Boulder Dam, is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the US states of Arizona and Nevada. It was constructed between 1931 and 1936 during the Great Depression and was dedicated on September 30, 1935, by President Franklin D. Roosevelt. -
President Franklin D. Roosevelt Elected President
He served for 12 years and four terms until his death in 1945, the only president ever to do so, and a central figure in world events during the mid-20th century, leading the United States during a time of worldwide economic depression and total war. -
21st Amendment
The Twenty-first Amendment to the United States Constitution repealed the Eighteenth Amendment to the United States Constitution, which had mandated nationwide Prohibition on alcohol on January 17, 1920. -
Computer Invention
The Atanasoff–Berry Computer (ABC) was the world's first electronic digital computer, albeit not programmable.[41] Atanasoff is considered to be one of the fathers of the computer.[42] Conceived in 1937 by Iowa State College physics professor John Atanasoff, and built with the assistance of graduate student Clifford Berry,[43] the machine was not programmable, being designed only to solve systems of linear equations. -
GI Bill of Rights
The GI Bill of Rights was created so that war veterans returning from WWII would have benifits after they returned home. -
Frisbee Invention
The Frisbie Baking Company (1871-1958) of Bridgeport, Connecticut, made pies that were sold to many New England colleges. Hungry college students soon discovered that the empty pie tins could be tossed and caught, providing endless hours of game and sport. Wham-O toy company roll out the first batch of their aerodynamic plastic discs--now known to millions of fans all over the world as Frisbees in 1957. -
Internet Invention
The first two nodes of what would become the ARPANET were interconnected between Leonard Kleinrock's Network Measurement Center at the UCLA's School of Engineering and Applied Science and Douglas Engelbart's NLS system at SRI International (SRI) in Menlo Park, California, on 29 October 1969.
