Today:
1138 – A massive earthquake strikes Aleppo, Syria, causing widespread destruction and deaths.
1531 – Huldrych Zwingli, a Swiss reformer, is killed in battle during the Second War of Kappel.
1634 – The Burchardi flood, one of the most severe North Sea floods, devastates the island of Strand in Denmark-Norway (now Germany), killing thousands.
1767 – Surveying for the Mason-Dixon Line between Pennsylvania and Maryland is completed.
1899 – The Second Boer War begins between the British Empire and the two Boer Republics in South Africa.
1910 – Theodore Roosevelt becomes the first U.S. president to fly in an airplane.
1939 – Albert Einstein sends a letter to President Franklin D. Roosevelt urging the development of atomic weapons, which leads to the creation of the Manhattan Project.
1950 – The Federal Communications Commission (FCC) issues the first license to CBS to broadcast in color.
1968 – NASA launches Apollo 7, the first manned mission in the Apollo program.
1984 – Astronaut Kathryn D. Sullivan becomes the first American woman to perform a spacewalk.