His father looked as if Ken had just uttered something absolutely unintelligible. "Start!" he cried. "Start what? How can we start anything? There's nothing left to work with, absolutely nothing!" Ken hesitated, an ache in his heart at the defeat he saw in his father's eyes. He held out his hands. "We've got these," he said. He tapped the side of his head. "And this." Professor Maddox's face seemed to relax a trifle. He looked at his son with a faint suggestion of a smile on his lips. "Yes? What do you propose to do with them?" Carefully, then, Ken outlined the results of his inventory. "Art can build up to six engines, if we need them. We've got plenty of electronic parts, and tubes big enough to put 60 or 70 kilowatts of supersonic energy in a beam. We don't want to build a little reflector again; we want to put up a full-scale instrument. When that's done, build another one, and still another, until we've used every scrap of material available in the valley. By that time maybe we'll have some cars running and can go to Frederick and other towns for more parts." Ken's father leaned back in his chair, his eyes closed. "If enthusiasm could do it, we could look forward to such a structure the day after tomorrow." "Maybe enthusiasm _can_ do it," said Professor Larsen quietly. "I believe the boy is right. We've let ourselves despair too much because of the fire. We still have the necessary principles in our heads. If Ken is right, we've got the materials. The only problem is that you and I are a pair of old, exhausted men, without the necessary enthusiasm and energy. Perhaps we can borrow enough of that from these boys. I'm in favor of undertaking it!" By the light of oil lamps they planned and talked until far past midnight. There were still no objections to be found outside the labor problem. When they were through, rough drawings and calculations for the first projector were finished. "Such a projector could surely reach well into the stratosphere," said Professor Larsen. "With the tremendous velocities of the air masses at those heights, one projector should be able to process hundreds of tons of atmosphere per day." "I am wondering," said Professor Maddox, "if we should not make the reflector parabolic instead of hyperbolic. We may disperse our energy too widely to be effective at high levels." "I think not. The parabola would narrow the beam to little more than its initial diameter and would concentrate the energy more than is required. With the power Ken speaks of, I believe the hyperbolic form could carry an effective wave into the stratosphere. We'll make some calculations for comparison tomorrow." * * * * * They authorized Ken to speak with the Sheriff the following day. "I've been wondering when I'd see some of you people," Johnson said bluntly. "What are you doing about the mess on the hill?" "My father thought maybe you'd drop in," said Ken.