Hugh Dorsey Gravitt, 74, whose car struck and killed author Margaret Mitchell. In August, 1949, the off-duty cabdriver struck Miss Mitchell as she walked with her husband, John Marsh, across Peachtree Street in downtown Atlanta. Five days later, the 48-year-old author of "Gone With the Wind" died. Gravitt was convicted of involuntary manslaughter and served about 10 months in prison. In a 1991 interview, he said that Miss Mitchell darted in front of his car and that he tried to miss her. In Cumming, Ga., on April 15 of unreported causes.