585 BC - The first known prediction of a solar eclipse was made in Greece.
1787 - The Constitutional convention opened in Philadelphia with George Washington presiding.
1844 - The gasoline engine was patented by Stuart Perry.
1844 - The first telegraphed news dispatch, sent from Washington, D.C., to Baltimore, MD, appeared in the Baltimore "Patriot."
1925 - John Scopes was indicted for teaching the Darwinian Theory in school.
1927 - Ford Motor Company announced that the Model A would replace the Model T.
1935 - Babe Ruth hit his final homerun, his 714th, and set a record that would stand for 39 years.
1961 - America was asked by U.S. President Kennedy to work toward putting a man on the moon before the end of the decade.
1968 - The Gateway Arch, part of the Jefferson National Expansion Memorial in St. Louis, MO, was dedicated.
1981 - Daredevil Daniel Goodwin scaled Chicago's Sears Tower, while wearing a "Spiderman" costume, in 7 1/2 hours.
1986 - Approximately 7 million Americans participated in "Hands Across America."
1992 - Jay Leno debuted as the new permanent host of NBC's "Tonight Show."
1997 – U.S. Senator Strom Thurmond became the longest-serving senator in U.S. history (41 years and 10 months).
2008 - NASA's Phoenix Mars Lander landed in the arctic plains of Mars.