"No--not in the way you mean. They could be conditioned to perform certain tasks, but usually they were controlled telepathically by the Ancients, who wore specialized helmet-transmitters for the purpose. The robots had radioatomic brains that reacted to telepathic commands. Then when the Silver Plague struck, the Ancients tried to escape by transplanting, not their physical brains, but their _minds_. I don't quite know how it was done. But the thought-patterns, the individual mental matrix, of each Ancient was somehow impressed on the radioatomic brain of a robot. Their minds were put into the robots' brains--and controlled the metal bodies. So they escaped the Plague. But they died anyway. Human, intelligent minds can't be transplanted successfully into artificial bodies that way. So--in a hundred years--they were dead, all of them." So that was the secret of the Ancients' disappearance from Ganymede. They had taken new bodies--and those bodies had killed them through their sheer alienage. Willard crushed out his cigaret-stub. "All the knowledge of the Ancients at my finger-tips, Ed. You can imagine what research I've done!" "I should have thought you'd have looked for a weapon against the Zarno," Garth said practically. "The Ancients were able to conquer them." "I did--first of all, after I'd learned how to work the recording-machines. A certain ray will destroy them--a vibrationary beam that shakes them to pieces, disrupts their molecular structure. The only trouble is--" Willard grinned sardonically. "It takes a damn good machine shop to build such a projector." "Oh. We couldn't--" "We couldn't. The Ancients left plenty of apparatus here, but not the right kind. Mostly records, and a lot of robots. Sorry, Ed, but unless you brought good weapons with you, you're stuck here with me." * * * * * Garth looked around to where his companions were standing motionless. "Yeah. Looks like it. Unless we can break through to that hangar of antigravity ships--" "We can't. The city's full of the Zarno, day and night. And there are always guards outside." Garth sighed. "The trouble is, unless we get out, nothing can stop the Silver Plague. Not to mention the fuel shortage. Wait a minute. You said the Zarno were superstitious--we tricked them once with a fake ceremony. Couldn't we try that again?" "I did," Willard told them. "It didn't work. The Zarno know what human beings are like now. Only the gods would impress them--those robots who once were their masters." Garth stopped breathing for a moment. "There's a way," he said. Willard looked at him. "I don't think so. When I saw you'd come back, I hoped for a minute--but it's no use. The Zarno are invulnerable to any weapons we can create here. We can't get out of the city!" "You said the gods would impress them." "The gods are dead--the Ancients." "Suppose one of them came back?" Willard caught his breath. "What do you mean?"