On Oct. 18, 1767, the Mason-Dixon line, the boundary between colonial Pennsylvania, Maryland and Delaware, was set as astronomers Charles Mason and Jeremiah Dixon completed their survey.
In 1867, the United States took formal possession of Alaska from Russia.
In 1892, the first long-distance telephone line between New York and Chicago was officially opened (it could only handle one call at a time).
In 1898, the American flag was raised in Puerto Rico shortly before Spain formally relinquished control of the island to the U-S.
In 1961, the movie musical “West Side Story,” starring Natalie Wood and Richard Beymer, premiered in New York, the film’s setting.
In 1962, James D. Watson, Francis Crick and Maurice Wilkins were honored with the Nobel Prize for Medicine and Physiology for determining the double-helix molecular structure of DNA.
In 1968, the U.S. Olympic Committee suspended Tommie Smith and John Carlos for giving a “Black power” salute as a protest during a victory ceremony in Mexico City.
In 1969, the federal government banned artificial sweeteners known as cyclamates (SY’-kluh-maytz) because of evidence they caused cancer in laboratory rats.
In 1972, Congress passed the Clean Water Act, overriding President Richard Nixon’s veto.
In 1977, West German commandos stormed a hijacked Lufthansa jetliner on the ground in Mogadishu, Somalia, freeing all 86 hostages and killing three of the four hijackers.
In 1997, a monument honoring American servicewomen, past and present, was dedicated at Arlington National Cemetery.
In 2001, CBS News announced that an employee in anchorman Dan Rather’s office had tested positive for skin anthrax. Four disciples of Osama bin Laden were sentenced in New York to life without parole for their roles in the deadly 1998 bombings of two U.S. embassies in Africa.
In 2010, four men snared in an FBI sting were convicted of plotting to blow up New York City synagogues and shoot down military planes with the help of a paid informant who’d convinced them he was a terror operative. (James Cromitie, David Williams, Onta Williams and Laguerre Payen were each sentenced to 25 years in prison.)