On this date in history:
In 1829, English scientist James Smithson left a will that eventually funded the establishment of the Smithsonian Institution in Washington -- in a country he never visited.
In 1844, Mormon founder Joseph Smith was slain by a mob at a jail in Carthage, Ill.
In 1847, the first telegraph wire links were established between New York City and Boston.
In 1859, Louisville, Ky., schoolteacher Mildred Hill composed a tune for her students and called it "Good Morning To You." Her sister, Patty, who wrote the lyrics, later added a verse that began "Happy Birthday To You."
In 1950, U.S. President Harry S. Truman ordered naval and air forces to help repel the North Korean invasion of South Korea.
In 1979, the U.S. Supreme Court ruled private employers could give special preferences to black people to eliminate "manifest racial imbalance" in traditionally white-only jobs.
In 1991, Associate Justice Thurgood Marshall announced he was retiring from the U.S. Supreme Court. He was the first African American to sit on the high court.
In 1995, the space shuttle Atlantis was launched from Cape Canaveral, Fla., on a historic mission to dock with the Russian space station Mir. Docking occurred two days later.
In 2003, the U.S. Federal Trade Commission opened a long-awaited nationwide registry for people who want to block unwanted telemarketing calls.
In 2005, Dennis Rader, the so-called "BTK" (bind, torture, kill) killer, pleaded guilty to 10 slayings in the Wichita, Kan., area. He was sentenced to life in prison.
In 2007, Tony Blair officially stepped down after a decade as British prime minister, submitting his resignation to Queen Elizabeth II. Blair was succeeded by Gordon Brown and became Britain's envoy to the Middle East.
In 2009, a top health official said the H1N1 virus, known as swine flu, killed 127 people of the more than 1 million infected in the United States. About 3,000 were reported hospitalized.
In 2011, a federal court jury in Chicago convicted former Illinois Gov. Rod Blagojevich on 17 felony corruption charges that included trying to sell the U.S. Senate seat vacated by Barack Obama after the 2008 presidential election. Blagojevich was sentenced to 14 years in prison.
In 2017, the FARC rebel group officially disarmed in a ceremony with the Colombian government.
In 2018, Supreme Court Justice Anthony Kennedy notified President Donald Trump he planned to retire from the high court. He stepped down July 31, 2018, and his replacement, Brett Kavanaugh, was sworn in Oct. 6, 2018.