IIMOONEY STARED AT HIS napping guest in a mood of wonder and fear and delight. Time traveler! But it was hard to doubt the pale-eyed man. He had said he was from the future and he mentioned a date that made Mooney gasp. He had said: “When you speak to me, you must know that my. Name? Is Harse.” And then he had curled up on the floor, surrounding his shiny briefcase like a mother cat around a kitten, and begun dozing alertly. But not before he showed Mooney just what it was he proposed to pay him with. Mooney sipped his cooling tea and forgot to shiver, though the drafts were fiercer and more biting than ever, now just before dawn. He was playing with what had looked at first like a string of steel ball-bearings, a child’s necklace, half-inch spheres linked together in a strand a yard lo