1892: Arthur Compton, who won a Nobel Prize for his discovery of the Compton Effect, where x-ray wavelengths change when colliding with electron in metal, was born. 1898: Waldo Semon, the inventor of PVC plastic, was born. 1934: Maxie Anderson, who co-piloted the first transatlantic balloon flight on the Double Eagle II, was born. 1935: "Popeye" was heard on NBC radio for the first time. 1939: Canada declared war on Germany. 1953: Swanson began selling its first "TV dinner." 1979: President Jimmy Carter granted clemency to four Puerto Rican nationalists who had been imprisoned for an attack on the U.S. House of Representatives in 1954 and an attempted assassination of President Truman in 1950. 1984: Jerome Hunsaker, who in 1916 was awarded the Massachusetts Institute of Technology's (MIT) first Ph.D. in aeronautical engineering, died. 1984: Alec Jeffreys discovered x-ray fingerprinting. 1993: "The X-Files" premiered on Fox Television. 1999: 11 FALN terrorists were set free from prison following clemency from President Clinton.