On this day, Feb. 28

1786 The Pennsylvania Legislature granted a charter for the Pittsburgh Academy “for the education of youth in useful arts, sciences and literature.” Judge Hugh Henry Brackenridge was the prime organizer.

1844 A 12-inch gun aboard the USS Princeton exploded as the ship was sailing on the Potomac River, killing Secretary of State Abel P. Upshur, Navy Secretary Thomas W. Gilmer and several others.

1953 Scientists James D. Watson and Francis H.C. Crick announced they had discovered the double-helix structure of DNA.

2018 Dick’s Sporting Goods said it would stop selling assaultstyle rifles and ban the sale of all guns to anyone under 21. Walmart announced it would no longer sell firearms and ammunition to those younger than 21 and would remove items resembling assault-style rifles from its website. The actions came two weeks after the mass shooting at Marjory Stoneman Douglas High School in Parkland, Fla. Some items are from Stefan Lorant’s “Pittsburgh: The Story of an American City” (digital.library.pitt.edu/chronology).

— Compiled by Alyssa Brown Today’s birthdays: Architect Frank Gehry, 90. Actor Gavin MacLeod, 88. Singer Sam the Sham, 82. Actor-director-dancer Tommy Tune, 80. Hall of Fame auto racer Mario Andretti, 79. Actress Bernadette Peters, 71. Nobel Prize-winning economist Paul Krugman, 66. Comedian Gilbert Gottfried, 64. Actor John Turturro, 62. Actress True O’Brien, 25.

Thought for today: “Who will give me back those days when life had wings and flew just like a skylark in the sky.”