Sutton gestured at the bubbling device behind him. "That thing is making air now, which we're going to need when the monster's in space. It was when we were still trying to find a poison for the beasts that I hit on the catalyst that makes their blood give up its oxygen--that's its blood flowing through the filters. We've got an electric generator running by tapping the monster's internal gas pressure. There are problems left before we'll be fully self-sufficient here--but the monster is so much like us in fundamental makeup that its body contains all the elements human life needs too." "Then," Westover glanced appreciatively around, "it looks like the main hazard is claustrophobia." "Don't worry about a cave-in. We're surrounded by solid cystoid tissue. But," Sutton's voice took on a graver note, "there may be other psychological dangers. I don't think all our people--there are fifty-one, fifty-two of us now--realize yet that this colony isn't just a temporary expedient. Human history hasn't had such a turning-point since men first started chipping stone. Spengler's _Mensch als Raubtier_--if he ever existed--has to be replaced by the _Mensch als Schmarotzer_, and the adjustment may come hard. We've got to plan for the rest of our lives--and our children's and our children's children's--as parasites inside this monster and whatever others we can manage to--infect--when they're clustered again in space." "For the future," put in the Preacher, who had watched benignly the biologists' reunion, "the Lord will provide, even as He did unto Jonah when he cried to Him out of the belly of the fish." "Amen," agreed Sutton. But the gaze he fixed on Westover was oddly troubled. "Speaking of the future brings up the question of the idea you mentioned--your monster-killing scheme." * * * * * Westover flexed his hands involuntarily, like one who has been too long enforcedly idle. In terse eager sentences he outlined for Sutton the plan that had burned in him during his bitter wandering over the face of the ruined land. It would be very easy to accomplish from an endoparasite's point of vantage, merely by isolating from the creature's blood over a long period enough of some potent secretion--hormone, enzyme or the like--to kill when suddenly reintroduced into the system. "Originally I thought we could accomplish the same thing by synthesis--but this way will be simpler." "Beautifully simple." Sutton smiled wryly. "So much so that I wish you'd never thought of it." Westover stared. "Why?" "Describing your plan, you sounded almost ready to put it into effect on the spot." "No! Of course I realize--Well, I see what you mean--I think." Westover was crestfallen. Sutton smiled faintly.