1867: Harvard School of Dental Medicine was established in Boston. It was the first U.S. dental school affiliated with a university.
1902: Willis Haviland Carrier began operating the first air conditioning system—which he invented, designed and built—at a printing company in Brooklyn, N.Y.
1918: The RMS Carpathia, the ship that rescued the 705 survivors from the RMS Titanic, was sunk off Ireland by the German submarine U-55, with five lives lost.
1945: The victorious Allies (United States, Britain and France) met in Potsdam, Germany, and abolished Nazism and Nazi organizations.
1955: Disneyland opened on 55 acres in Anaheim, Calif.
1962: Major Robert Michael White flew the X-15 rocket jet to an altitude of 314,750 feet (59 miles, 96 km). This qualified him for an Astronaut Badge, becoming the first “Winged Astronaut,” one of few who have flown into space without a conventional spacecraft.
1925: Adolf Hitler published his personal manifesto, Mein Kampf.
1976: Nadia Comăneci became the first person in Olympic Games history to score a perfect 10 in gymnastics at the 1976 Summer Olympics in Montreal, Quebec.
1848: Bloomers were introduced for the first time at the first Women’s Rights Convention in Seneca Falls, N.Y.
1947: Born this day: musicians Bernie Leadon (The Eagles, The Flying Burrito Brothers, Nitty Gritty Dirt Band), and Brian May (Queen).
1952: The 15th Summer Olympics opened in Helsinki, Finland.
1983: The first three-dimensional reconstruction of a human head in a CT scan was published.
1807: The first internal combustion engine was patented in France.
1851: At the Benicia Army station near San Francisco, Calif., troops on the marching ground were rained on by a shower of blood and chunks of beef. No explanation for the event has ever been found.
1940: California opened its first freeway, the Arroyo Seco Parkway, connecting Los Angeles with Pasadena.
1960: The Polaris missile was successfully launched from a submerged submarine, the USS George Washington, for the first time.
1968: The first International Special Olympics Summer Games were held at Soldier Field in Chicago, for about 1,000 athletes with intellectual disabilities.
1969: Neil Armstrong and Buzz Aldrin became the first humans to walk on the moon. Upon placing his foot on the lunar surface, Armstrong declared: “That’s one small step for a man, one giant leap for mankind.”
1873: The Jesse James gang pulled off the first successful train robbery in the Old West.
1918: German submarine U-156 shelled Nauset Beach in Orleans, Mass.
1925: High school biology teacher John T. Scopes was found guilty of teaching evolution in class in Dayton, Tenn., and fined $100.
2007: Harry Potter and the Deathly Hallows, the fastest-selling novel ever, was published. It sold 15 million copies in the first 24 hours of its release.
2011: NASA’s Space Shuttle program ended with the landing of Space Shuttle Atlantis on mission STS-135. This became the first time since 1961 that the United States had no means to launch astronauts into space.
1923: Born this day: U.S. presidential candidate, Sen. Bob Dole, and wrestler The Fabulous Moolah (died 2007).
1991: Serial murderer/ cannibal Jeffrey Dahmer was arrested in Milwaukee after police discovered human remains in his apartment.
1829: William Austin Burt of Chicago patented the typographer, a precursor to the typewriter.
1904: The ice cream cone was invented at the World’s Fair in St. Louis.
1983: Air Canada Flight 143, a Boeing 767-233, ran out of fuel and glided to a landing at Gimli airport, Manitoba.
1984: Vanessa Williams became the first Miss America to resign when she surrendered her crown after nude photos of her appeared in Penthouse magazine.
1995: Comet Hale-Bopp was discovered. (It became visible to the naked eye nearly a year later.)