If the girl had given Don Cort more than that one glance, or if it had been a trained, all-encompassing glance, she would have seen a man in his mid-twenties--about her age--lean, tall and straight-shouldered, with once-blond hair now verging on dark brown, a face neither handsome nor ugly, and a habit of drawing the inside of his left cheek between his teeth and nibbling at it thoughtfully. But it was likely that all she noticed then was the brief case he carried, attached by a chain to a handcuff on his left wrist. "Will we be here long?" Don asked the conductor. He didn't want to miss his plane at Columbus. The sooner he got to Washington, the sooner he'd get rid of the brief case. The handcuff it was attached to was one reason why his interest in the redhead had been only passing. "Can't say," the conductor told him. He let the door close again and went down to the tracks. Don hesitated, shrugged at the redhead, said, "Excuse me," and followed the conductor. About a dozen people were milling around the train as it sat in the dark, hissing steam. Don made his way up to the locomotive and found a bigger knot of people gathered in front of the cowcatcher. Some sort of barricade had been put up across the tracks and it was covered with every imaginable kind of warning device. There were red lanterns, both battery and electric; flashlights; road flares; and even an old red shirt. Don saw two men who must have been the engineer and the fireman talking to an old bearded gentleman wearing a civil defense helmet, a topcoat and riding boots. "You'd go over the edge, I tell you," the old gentleman was saying. "If you don't get this junk off the line," the engineer said, "I'll plow right through it. Off the edge! you crazy or something?" "Look for yourself," the old man in the white helmet said. "Go ahead. Look." The engineer was exasperated. He turned to the fireman. "You look. Humor the old man. Then let's go." The bearded man--he called himself Professor Garet--went off with the fireman. Don followed them. They had tramped a quarter of a mile along the gravel when the fireman stopped. "Okay," he said "where's the edge? I don't see nothing." The tracks seemed to stretch forever into the darkness. "It's another half mile or so," the professor said. "Well, let's hurry up. We haven't got all night." The old man chuckled. "I'm afraid you have." They came to it at last, stopping well back from it. Professor Garet swelled with pride, it seemed, as he made a theatrical gesture. "Behold," he said. "Something even Columbus couldn't find. The edge of the world." True, everything seemed to stop, and they could see stars shining low on the horizon where stars could not properly be expected to be seen.