"It is one of the miracles. The records tell of it. They landed near the light! The light at that time encompassed a very small area, only a few miles. Gravity there was normal, but beyond, it was very heavy. They investigated the center of light and found the Stone." * * * * * Brownell was excited. "I suspected something like this! The Stone? What is it?" "We still do not know, except that it supplies us with light and normal gravity and a temperate zone very favorable to our crops. It defies our science, and it certainly must have come from somewhere far beyond our solar system! Our ancestors found it deeply buried and dug it out. The moment they did--" "Yes?" "The light from it spread slowly, very slowly. In about ten years' time it had encompassed this entire hemisphere, stopped only by the sharp curvature of the planet." "And as the light spread outward, the heavy gravity vanished?" "That is true. We have the Stone now atop our hill, which is the highest spot. Our ancestors, however, had to fight for it time and again. The Perlacs at that time were really savages. They had known of the buried light but were afraid to approach it. Later they tried to get the Stone, but were always driven back into the darkness. They have warred on us ever since--for generations! "In the last few years they have become very strong. They are using explosives now. I believe that ages ago, long before the first Earthmen came, a civilization existed and died here. The present Perlacs must have discovered remnants of an ancient science, and are slowly reviving it!" There was a moment of silence. Janus took advantage of it to hand his atomic rifle to the girl, and his neutro-pistol as well. "Have you ever seen weapons like these?" She examined them excitedly, especially the neutro-pistol. "Donli, look at this!" she pointed at the firing coils. "It seems to be the same principle we're working on!" "Do you mean to say you're trying to invent a neutro gun?" Janus was amazed. "Yes," Donli answered. "We've been working on it for the past several years, but it's been slow and hard. Sometimes disastrous." He stepped to a bookcase, brought out one of the ancient volumes. It was Spurlin's _Evolution and Control of the Free Electron_. "We've worked from the principles set forth here," Donli explained, "and with some slight measure of success. But we feel that we're treading on dangerous ground. Only a few months ago one of our laboratories was blown up and four men killed." Brownell nodded. "Even when Spurlin wrote that book there was no real control of the electron. It came later. Anyway, we can help you now! We have the real models here to work from. Would you like to see these guns in operation?" It was a needless question. They repaired outside, where Janus demonstrated the atomic rifle first, aiming at a harmless clump of bushes some fifty yards away. The atomic pellet struck and exploded, leaving a miniature crater.