Dave grunted at his own stupidity. That really simplified things, since it meant only one control for all of them and the sky itself. But designing a machine to handle the planets and the sun, while a lot simpler, was still a complex problem. With time, it would have been easy enough, but there was no time for trial and error. He ripped up his plans and began a new set. He'd need a glass sphere with dots on it for the stars, and some kind of levers to move the planets and sun. It would be something like the orreries he'd seen used for demonstrations of planetary movement. Ser Perth came over again, staring down at the sketch. He drowned in doubt. "Why waste time drawing such engines? If you want a model to determine how the orbits should be, we have the finest orrery ever built here in the camp. We brought it with us when we moved, since it would be needed to determine how the sky should be repaired and to bring the time and the positions into congruence. Wait!" He dashed off, calling two of the mandrakes after him. In a few minutes, they staggered back under a bulky affair in a protective plastic case. Ser Perth stripped off the case to reveal the orrery to Hanson. It was a beautiful piece of workmanship. There was an enormous sphere of thin crystal to represent the sky. Precious gems showed the stars, affixed to the dome. The whole was nearly eight feet in diameter. Inside the crystal, Hanson could see a model of the world on jeweled-bearing supports. The planets and the sun were set on tracks around the outside, with a clockwork drive mechanism that moved them by means of stranded spiderweb cords. Power came from weights, like those used on an old-fashioned clock. It was obviously all hand work, which must make it a thing of tremendous value here. "Sather Fareth spent his life designing this," Ser Perth said proudly. "It is so well designed that it can show the position of all things for a thousand centuries in the past or future by turning these cranks on the control, or it will hold the proper present positions for years from its own engine." "It's beautiful workmanship," Hanson told him. "As good as the best done on my world." Ser Perth went away, temporarily pleased with himself, and Hanson stood staring at the model. It was as good as he'd said it was--and completely damning to all of his theories and hopes. No model he could make would equal it. But in spite of it and all its precise analogy to the universe around him, the sky was still falling in shattered bits! Sather Karf and Bork had come over to join Hanson. They waited expectantly, but Hanson could think of nothing to do. It had already been done--and had failed. The old man dropped a hand on his shoulder. There was the weight of all his centuries on the Sather, yet a curious toughness showed through his weariness. "What is wrong with the orrery?" he asked.