1767 – Surveying for the Mason–Dixon line separating Maryland from Pennsylvania is completed.
1811 – Inventor John Stevens' boat, the Juliana, begins operation as the first steam-powered ferry (service between New York City, New York, and Hoboken, New Jersey).
1862 – In the aftermath of the Battle of Antietam, Confederate General J.E.B. Stuart and his men loot Chambersburg, Pennsylvania, during a raid into the north.
1890 – In Washington, D.C., the Daughters of the American Revolution is founded.
1910 – Former President Theodore Roosevelt becomes the first U.S. president to fly in an airplane. He flew for four minutes with Arch Hoxsey in a plane built by the Wright brothers at Kinloch Field (Lambert–St. Louis International Airport), St. Louis, Missouri.
1950 – CBS's mechanical color system is the first to be licensed for broadcast by the U.S. Federal Communications Commission.
1972 – A race riot occurs on the United States Navy aircraft carrier Kitty Hawk off the coast of Vietnam during Operation Linebacker.
1975 – The NBC sketch comedy/variety show Saturday Night Live debuts with George Carlin as the host and Andy Kaufman, Janis Ian and Billy Preston as guests.
1976 – George Washington's appointment, posthumously, to the grade of General of the Armies by congressional joint resolution Public Law 94-479 is approved by President Gerald R. Ford.
2000 – NASA launches STS-92, the 100th Space Shuttle mission, using Space Shuttle Discovery.
