"I know all that," Norris said impatiently. "But suppose we've run into a new kind of life there--one based on radioactive matter? Biologists have speculated on it more than once. Theoretically, creatures of radioactive matter could exist, drawing their energies not from chemical metabolism as we do, but from the continuous process of radioactive disintegration." "Theoretically, the sky is a big roof with holes in it that are stars," growled Kincaid. "It depends on whose theory you believe." "Every time a Proxy has blacked out down there, there's been little clouds of heavy radioactive gas near," argued Doug Norris. "Each seems to have a denser core. Suppose that core is an unknown radium compound, evolved into some kind of neuronic structure that is able to receive and remember stimuli? A sort of queer, radioactive brain? "If that's so, and biologists have said it's possible, the _body_ of the creature consists of radon gas emanated from the radium core. You remember the half-life of radon exactly equals the rate of its emission from radium, so there'd be a constant equilibrium of the thing's gaseous body, analogous to our blood circulation. Given Mercury's conditions, it's no more impossible than a jellyfish or a man here on Earth!" * * * * * Kincaid looked skeptical. "And you think these hypothetical living Raddies of yours are attacking our Proxies? Why would they?" "If they have cognition and correlation faculties they might be irritated by the tube emanations from the control-boxes of our Proxies," Norris suggested. "They get into those control-boxes and wreck the tube circuits by overloading the electron flow with their own Beta radiation!" "It's all pretty far-fetched," muttered his superior. "Radioactive life! But all those Proxies blowing can't be just chance." He paused, then added gloomily, "But I can just see myself telling a World Council committee that your hypothetical living Raddies are what keep us from delivering uranium! Hurriman would like that. It would convince the Council that I'm as incompetent as he claims." "He'll convince the Council of that anyway unless we deliver uranium from Mercury quickly," retorted Norris. "And we'll never do it till we get these Raddies licked. They're basically just complex clouds of radioactive gas. A Proxy armed with a high-pressure gas hose should be able to blow them to rags. Can't we try it, Mart?" Kincaid sighed, and stood up. "I was a practical man once," he said wearily, "and would have booted you out of here if you'd suggested such stuff. But I'm a drowning man right now, so I'll buy your straw. We'll send down a couple of Proxies armed with gas hoses and see how they make out." Doug Norris eagerly went with his superior into the adjoining room where the operators of the Base Proxies were on duty. "Norris and I will take over two Proxies at base," Kincaid told the sub-chief there.