He suddenly knew that. He knew why it was so. He could have explained it completely and precisely. But he didn't know how he knew. The items that added together were themselves so self evident that he didn't even wonder how he knew them. They _had_ to be so! * * * * * Cathy said muffledly, her face against his shoulder, "But we won't be alive in a couple of weeks, Lon. We can't live long past daybreak." He did not answer. There were more ideas coming into his mind. He didn't know where they came from. But again they were such self evident, unquestionable facts that he did not wonder about them. He simply paid tense, desperately concentrated attention as they formed themselves. "We--may live," he said shakily. "There's an ionosphere up at the top of the atmosphere here, just like there is on Earth. It's made by the sunlight ionizing the thin air. The--stronger sunlight will multiply the ionization. There'll be an--actually conducting layer of air.... Yes.... The air will become a conductor, up there." He wet his lips. "If I make a--gadget to--short-circuit that conducting layer to the ground here.... When radiation photons penetrate a transparent conductor--but there aren't any transparent conductors--the photons will--follow the three-finger rule.... "They'll move at right angles to their former course--" He swallowed. Then he got up very quietly. He put her aside. He went to his tool shed. He climbed to the roof of the barn now filled with _thanar_ leaves. He swung his axe. The barn was roofed with aluminum over malleable plastic. The useful property of malleable plastic is that it does not yield to steady pressure, but does yield to shock. It will stay in shape indefinitely under a load, but one can tap it easily into any form one desires. Lon swung his axe, head down. Presently he asked Cathy to climb up a ladder and hold a lantern for him. He didn't need light for the rough work--the burning desert vegetation gave enough for that. But when one wants to make a parabolic reflector by tapping with an axe, one needs light for the finer part of the job. * * * * * In Cetopolis, Carson agitatedly put his records on tape and sent it all off by spacegram. He'd previously reported on Lon Simpson, but now he knew that he was going to die. And he followed his instinct to transmit all his quite useless records, in order that his superiors might realize he had been an admirable employee. It did not occur to him that his superiors might be trying frantically to break his sending beam to demand that he find out how Lon Simpson made his power gadget and how he converted vegetation, before it was too late. They didn't succeed in breaking his beam, because Carson kept it busy. He was true to type.