Mute with an even greater wonder than before, Harwich and Arnold stared around them. The room was gigantic, soaring up in a huge, metal-ribbed dome. Scores of crystal-walled passages led into this colossal chamber of secrets. The whole immense Tower building was transparent, except that some darkening pigment had been added to the material that composed it, 'till it was like bluish glass. Through it the desolate surrounding hills of Io could be seen, and the cages, filled with those aimless, pathetic, sluglike creatures. But the attention of the two men was drawn inevitably to the center of the room. Rearing up there, under the rotunda of the dome, was a massive, lavender-sheened pyramid. It gave a steady, throbbing sound, as of countless tiny wheels and shafts whirling inside it, working cams and rods, and who knew what else? "Dammit!" Evan Harwich kept muttering under his breath in dim confusion. "Dammit." He was used to machinery, yes. He was used to the roar of rockets, and to the delicate instruments used in space flight. But this was machinery of a far higher order. That busy, vibrating pyramid, squatting there like some huge idol, somehow seemed to possess a definite personality of its own! Suddenly Paul Arnold clutched the patrol pilot's arm. "I wonder if I believe what I see!" he whispered tensely. "Look!" Harwich's gaze followed the lines of the boy's pointing finger to something quite near--so near, and seemingly so insignificant in this vast, somber, throbbing interior, that he had not noticed before. Just at the base of the pyramid there was an artistic little structure, consisting of four slender pillars and a roof. It looked like a small, ornamental kiosk or arbor, so artfully were the scientific details of it--the coils in its top, and the delicate filaments that pronged from them--concealed in the decorative metal scroll-work. Within the pillared structure, somehow, there stood a man--an Earthman. His heavy body was clad now in a rocketeer's leather coverall. At his waist dangled a heat pistol, and on his fat face there was a strange, wild sort of smirk. "Howdy, boys!" he greeted. "Yes, it's me--George Bayley, the guy who used to keep a print shop in Ganymede City! I've been here longer than you have, and I've been able to find out more. Pretty nice, huh? The people of Io had science perfected before they became extinct. Everything was done by machines, even investing. Not a bit of work to do any more. And if they wanted anything special, they just came into this little coop, here, and wished." * * * * * Bayley paused, still smirking. His loud voice had seemed distant in that great room, and vibrant with awe. Harwich and Arnold stared at him for a moment, neither knowing quite what to say, or what to believe. And what was that which had just spilled from his lips, as though he had been a little afraid of the statement himself? About perfected science, and wishing?