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?"