The long train, which for nearly an hour had been gliding smoothly forward with a soothing, cradling motion of its heavy trucked Pullmans, and a crooning, lullaby sound of its droning wheels, came to a jarring stop at one of the mountain stations, and Lieutenant Allison wakened with a start. The echo of the laugh that he had heard in his dream still sounded in his ears, a tantalizing, compelling note, elusive as the Pipes of Pan, luring as a will-o'-the-wisp.