Don Cort and the fireman walked cautiously toward the edge while the professor ambled ahead with the familiarity of one who had been there before. But there was a wind and they did not venture too close. Nevertheless, Don could see that it apparently was a neat, sharp edge, not one of your old ragged, random edges such as might have been caused by an explosion. This one had the feeling of design behind it. Standing on tiptoe and repressing a touch of giddiness, Don looked over the edge. He didn't have to stand on tiptoe any more than he had to sit on the edge of his seat during the exciting part of a movie, but the situation seemed to call for it. Over the edge could be seen a big section of Ohio. At least he supposed it was Ohio. Don looked at the fireman, who had an unbelieving expression on his face, then at the bearded old man, who was smiling and nodding. "You see what I mean," he said. "You would have gone right over. I believe you would have had a two-mile fall." * * * * * "Of course you could have stayed aboard the train," the man driving the old Pontiac said, "but I really think you'll be more comfortable at Cavalier." Don Cort, sitting in the back seat of the car with the redhead from the club car, asked, "Cavalier?" "The college. The institute, really; it's not accredited. What did you say your name was, miss?" "Jen Jervis," she said. "Geneva Jervis, formally." "Miss Jervis. I'm Civek. You know Mr. Cort, I suppose." The girl smiled sideways. "We have a nodding acquaintance." Don nodded and grinned. "There's plenty of room in the dormitories," Civek said. "People don't exactly pound on the gates and scream to be admitted to Cavalier." "Are you connected with the college?" Don asked. "Me? No. I'm the mayor of Superior. The old town's really come up in the world, hasn't it?" "Overnight," Geneva Jervis said. "If what Mr. Cort and the fireman say is true. I haven't seen the edge myself." "You'll have a better chance to look at it in the morning," the mayor said, "if we don't settle back in the meantime." "Was there any sort of explosion?" Don asked. "No. There wasn't any sensation at all, as far as I noticed. I was watching the late show--or trying to. My house is down in a hollow and reception isn't very good, especially with old English movies. Well, all of a sudden the picture sharpened up and I could see just as plain. Then the phone rang and it was Professor Garet." "The old fellow with the whiskers and the riding boots?" Jen Jervis asked. "Yes. Osbert Garet, Professor of Magnology at the Cavalier Institute of Applied Sciences." "Professor of what?" "Magnology. As I say, the school isn't accredited. Well, Professor Garet telephoned and said, 'Hector'--that's my name, Hector Civek--'everything's up in the air.' He was having his little joke, of course. I said, 'What?' and then he told me." "Told you what?" Jen Jervis asked. "I mean, does he have any theory about it?"