June 15

1752: Ben Franklin's kite-flying experiment proved lightning and electricity were related. 1785: Balloonists de Rozier and Romain died in world's first fatal aviation accident. 1844: Charles Goodyear was granted a patent for the process vulcanizing process that strengthens rubber. 1877: Henry O. Flipper became the first African American to graduate from the U.S. Military Academy at West Point. 1919: Capt. John Alcock and Lt. Arthur W. Brown won $50,000 for successfully completing the first, non-stop trans-Atlantic plane flight. 1924: Ford Motor Company manufactures its 10 millionth Model-T automobile. 1924: Radio Bloemendaal (Netherlands) began broadcasting. 1985: National Justice for Janitors Day was first celebrated.1992: The first Berlin Air Show in 60 years was held. 1995: John Atanasoff, who was belatedly credited as the builder of the first electronic digital computer (the Atanasoff-Berry Computer, ABC), died.