Jim Palmer sucked in his breath with an audible gasp, and muscles rippled in his heavy shoulders as his arms came up in a threatening gesture. "You're making a mistake, Denton," he said brittlely. And, without warning, his face white and strained, he sprang at the other, his whipping arms smashing the guns aside. The twin ati-guns roared in a wailing scream of unleashed power, their released streams of energy charring the ground, as Don Denton's hands clenched in sudden reflex. Then the guns were hammered aside, and the bull-like body of Jim Palmer was straining at the trouble shooter's lithe strength. For one interminable instant, Don Denton wavered on his feet, then he went backward, carried by the other's weight, his mind numbed by the paralyzing shock that came from a sledge-like fist hammering at his chest. He rolled as he fell, twisted, and his right hand lashed out in a desperate effort to reach one of the fallen guns. A heavy knee pinned his arm to the ground, and he gasped from Palmer's weight on his chest. He arched his body, tossed Palmer to one side, smashed at him with a two-handed attack that hurled the heavy man a dozen feet away. He slipped as he tried to follow his advantage, felt Palmer's hands tearing at the globe of his oxy-helmet. He felt a lace break below his chin, and then his right hand came up in a vicious right cross. Palmer sagged, half unconscious from the blow, went entirely slack, as the trouble shooter crossed his left and then his right. Don Denton crouched for a moment, staring into the blank face of the camp manager, his chest heaving, feeling a slight dizziness as the air of Venus mingled with that of his damaged oxy-helmet. Then the wailing hiss of an ati-gun brought him to his feet. He dived for his twin guns, turned, raced for the safety of the Comet, feeling the tingle of released energy as his cellu-ray suit dissipated the shock of a direct ati-blast on his back. He fired twice, as a warning gesture, at the men streaming from the rendering shed, smiled grimly as the tight knot of pursuers broke into individuals. And then he was at his ship, the vibra-ray lock swinging the port open automatically. He spun through the port, cogged it shut behind him, sagged against its solid friendliness, utterly worn with the