A panel telescoped silently into itself. It opened on a cylindrical chamber that had seemingly been made of a single sheet of metal, so flawlessly had the banks of control boards which it contained been built into it. The soft green-blue glow with which the chamber was suffused was generated by an ingredient of the metal itself. Circling the room at about shoulder height was a continuous row of what were obviously telescreens; below and above them were the banks of machines which were constructed according to an electro-mechanical concept with which Cragin was totally unfamiliar. According to Earth standards, it was so much junk, a distorted caricature of scientific equipment. And in the center of the chamber, just at eye level, was what Cragin knew must be the "brain" of the entire assembly. A cylinder within a cylinder, its inner workings thoroughly screened by a shifting yet motionless opalescence through which he could not see. What lied in the heart of the thing would be as completely beyond his knowledge as were the visible machines over which it was master. The girl watched him as his eyes remained fixed on it. "It's the power source, as far as we could determine. For everything." "For the entire planet." "For the entire solar system." "Sure, but not today." "Not only for today, but for all time. Gravity, warp, everything. If you don't believe me, try explaining the difference between Space as it exists inside and outside the Barrier sometime. Those--" she gestured toward the upper rows of machines, "control the power. When you know how to manipulate them, you can move any body within the system at will--in any direction, at any speed. The sun itself, if you want to." "All right, I'll admit it's smooth," Cragin said. His hands went to his hips, resting just an inch or so above the butts of his Krells. "You're a fantastic man, Cragin." "_I_--" and he laughed a little. "The trouble is, Miss Griffin, you people just never know when to quit. The average Patrol officer may not have much imagination; police never were supposed to have. It's true if you spin a good enough yarn to begin with, you might get away with it. But if you take it too far--well, it's sort of like overacting a part. The audience just doesn't believe it any more. You might almost have convinced me, I'll admit. But as it is--" His words were falling uselessly about him. Lin Griffin had begun her work near the largest of the telescreens. In a moment she had made it come alive, and in a moment more Cragin was watching the entire system. She made another adjustment, and he was watching Earth alone. A second later, he was watching Earth, Venus and Mercury in their stolid journeys around the sun. Something that sounded very much like a comptometer was whining somewhere, and he watched as the girl began working a three dimensional orbit plot.