"It was just that which their gravity-condenser accomplished. In a low pit at the heart of one of their cities--this city, in fact--they placed the condenser, a mass of brilliant hemispherical ray-attracters which caused more of the Galaxy's outward-shooting attractive force to fall upon the dark star, which condensed and concentrated that radiating force upon the dark star, thereby pulling the dark star inward toward the Galaxy's edge in a great curve. When they reached a distance of three billion miles from the Galaxy's edge they planned to turn off the great condenser, and their dark star would then shoot past the Galaxy's edge, jerking out our sun with it, from that edge, by its own terrific gravitational grip. If the condenser were turned off before they came that close, however, they would pass the sun at a distance too far to pull it out with them, and would then speed on out into space alone, toward the freezing of their world and their own extinction. For that reason the condenser, and the great cage-switch of the condenser, were guarded always by hovering cones, to prevent its being turned off before the right moment. "Since then they have kept the great gravity-condenser in unceasing operation, and their dark star has swept in toward the Galaxy's edge in a great curve. Back in our own solar system I saw and understood what would be the result of that inward curve, and so we came here--and were captured. And in those weeks since we were captured, while you have lain here unconscious and raving, this dark star has been plunging nearer and nearer toward our Galaxy and toward our sun. Ten more days and it passes that sun, carrying it out with it into the darkness of boundless space, unless the great condenser is turned off before then. Ten more days, and we lie here, powerless to warn any of what forces work toward the doom of our sun!" * * * * * There was a long silence when Hurus Hol's voice had ceased--a whispering, brain-crushing silence which I broke at last with a single question. "But Nal Jak----?" I asked, and the faces of my two companions became suddenly strange, while Dal Nara turned away. At last Hurus Hol spoke. "It was after the tentacle-scientists had examined me," he said gently, "that they brought Nal Jak down to examine. I think that they spared me for the time being because of my apparently greater knowledge, but Nal Jak they--vivisected."