Larry Wilson was going to miss his train. He swung from his cab at Philadelphia's Broad Street Station, glanced swiftly at his wrist-watch, tossed a bill in the general direction of the cabby, then dashed for the staircase that led to the train platform. His watch showed exactly 10:59. The New York express was scheduled to leave at eleven sharp. Behind him, morning traffic made its customary din in the streets of the Quaker City. Automobile horns whonked belligerently. Radio loudspeakers blared