Aug. 1 (UPI) -- On this date in history:
In 1498, Italian explorer Christopher Columbus set foot on the American mainland for the first time, at the Paria Peninsula in present-day Venezuela.
In 1790, the first U.S. census showed a population of 3,929,214 people in 17 states.
In 1907, an Aeronautical Division was added to the Army Signals Corps. The first aircraft bought by this forerunner of the U.S. Air Force was built by the Wright brothers.
In 1961, the first Six Flags amusement park opened on 212 acres in Arlington, Texas. In its opening year, admission for adults cost $2.75 and for children cost $2.25.
In 1966, Charles Whitman killed 16 people, including his wife and mother, in Austin, Texas. Thirty-two people were wounded. Most of Whitman's victims were struck by shots fired from the University of Texas Tower. The gunman, a student and ex-Marine, was killed by a police officer.
In 1977, Francis Gary Powers, pilot of a U-2 spy plane shot down over the Soviet Union in 1960, was killed in the crash of his weather helicopter in Los Angeles.
In 1981, MTV premiered with the Buggles' "Video Killed the Radio Star."
In 2004, nearly 400 people died in a supermarket fire on the outskirts of Asuncion, Paraguay.
In 2007, an eight-lane bridge across the Mississippi River at Minneapolis, collapsed during the evening rush hour, killing 13 people and injuring nearly 150. About 50 vehicles were thrown into or near the water when the steel-and-concrete Interstate 35W span buckled and fell.
In 2010, a worldwide ban on cluster bombs went into effect. Cluster bombs, usually dropped from planes, are filled with smaller anti-personnel bombs, which are scattered over wide areas.
In 2011, when the U.S. House of Representatives approved the deficit reduction bill, one of the "yes" votes was cast by Rep. Gabrielle Giffords, D-Ariz., taking part in her first congressional business since she was shot in the head in an assassination attempt in January in Tucson. She was greeted with a standing ovation.