He gazed at his handiwork. No, darn it, that was just what grownups wanted you to do. This grass couldn't be hurt. You couldn't pull it up or tear it off; it hurt your fingers to try. A rub with the side of the crayon removed the sign. He thought for a moment, then wrote: KEEP OFF THE GRASS. With an untroubled countenance, he sprang up and hurried after the others. Joggy and the older boy were swimming lazily through the air at shoulder height. In the pavement directly under each of them was a wide, saucer-shaped depression which swam along with them. The uninjes avoided the depressions. Darter was strutting on his hind legs, looking up inquiringly at his master. "Gimme a ride, Hal, gimme a ride!" the Butcher called. The older boy ignored him. "Aw, gimme a ride, Joggy." "Oh, all right." Joggy touched the small box attached to the front of his broad metal harness and dropped lightly to the ground. The Butcher climbed on his back. There was a moment of rocking and pitching, during which each boy accused the other of trying to upset them. Then the Butcher got his balance and they began to swim along securely, though at a level several inches lower. Brute sprang up after his master and was invisibly rebuffed. He retired baffled, but a few minutes later, he was amusing himself by furious futile efforts to climb the hemispherical repulsor field. Slowly the little cavalcade of boys and uninjes proceeded down the Avenue of Wisdom. Hal amused himself by stroking toward a tree. When he was about four feet from it, he was gently bounced away. * * * * * It was really a more tiring method of transportation than walking and quite useless against the wind. True, by rocking the repulsor hemisphere backward, you could get a brief forward push, but it would be nullified when you rocked forward. A slow swimming stroke was the simplest way to make progress. The general sensation, however, was delightful and levitators were among the most prized of toys. "There's the Theater," Joggy announced. "I _know_," the Butcher said irritably. But even he sounded a little solemn and subdued. From the Great Ramp to the topmost airy finial, the Time Theater was the dream of a god realized in unearthly substance. It imparted the aura of demigods to the adults drifting up and down the ramp. "My father remembers when there wasn't a Time Theater," Hal said softly as he scanned the facade's glowing charts and maps. "Say, they're viewing Earth, somewhere in Scandinavia around zero in the B.C.-A.D. time scale. It should be interesting." "Will it be about Napoleon?" the Butcher asked eagerly. "Or Hitler?" A red-headed adult heard and smiled and paused to watch. A lock of hair had fallen down the middle of the Butcher's forehead, and as he sat Joggy like a charger, he did bear a faint resemblance to one of the grim little egomaniacs of the Dawn Era. "Wrong millennium," Hal said.