"It seems that the Ancients can only control areas where their contact-material is present. Until the mineral was found by Earth scientists, that place was on Mars only. Then some of the material was taken back to Earth, for museums, for analysis, and even for paperweights and such. My guess is that one of the technicians who runs the Brain has a hunk of the stuff on his desk, right?" Baxter narrowed his eyes, then relaxed and nodded. "Yes. As soon as I figured out the Brain had been gimmicked, I went there to check. I had it removed immediately. Then I refed the data into the Brain, and found the name of the man who should have been sent here to destroy the Ancients." I nodded. "Your own. Philip Baxter. Which is why you sped up here so damned fast after I arrived. And also why you had to toss me into a cell. One thing eludes me, though. What gave you the hint that the Brain might have been rigged?" Baxter smiled wearily. "Your loss of the Amnesty. When these idiots here called me, my first reaction was to chew them out and to have you released. It was only after talking to you that it dawned on me that you seemed ill-equipped for the task I had in mind. I got to wondering about the Brain, then. That's when I went over to see for myself, and found the parabolite." I nodded again. "Yes. In their cavernful of the stuff, they could float me all over the place. When some of the stuff was near the Brain, they could control that. But nothing else. Nothing that was not in the presence of the mineral. That is, excepting one part of the mineral: the chunk that comprises the false Amnesty. Something had to happen to that hunk of it. Something that simultaneously rendered that piece out of their control, and told them that you were a menace to their existence in this dimension." "If you think I'll tell you that--" he said angrily.