He almost dragged the stunned Kincaid into the deserted office, to the control-boards of the Proxies at Base. "Take over a Proxy and follow me," Norris ordered. "I've an idea that if we go down in that fissure again, we can prove it." "Prove what?" Kincaid asked, but mechanically obeyed and took over a Proxy control. Again, Norris and Kincaid guided their Proxies out of Base and across the seared Mercury plain toward Fissure Four. Norris peered down into the fissure as he advanced. Then as they glimpsed the wrecked Proxies they had previously left there, they also glimpsed glowing little clouds flowing rapidly toward them. A Raddy lifted its glowing gaseous body to envelop the control-box of Norris' Proxy. Again, as he stared into the thing's brilliant, pulsing core, he felt his senses reel queerly. But this time, he knew beyond any doubt what it was. "Hypnosis!" he yelled to Kincaid. "Hypnosis operating through our Proxies' eyes right back along the beam to our own eyes and brains! I thought so!" His shout died away as his brain reeled under the powerful hypnotic influence of the Raddy's pulsing, starlike core. Hypnosis could operate by vision, everyone knew that. Nobody had dreamed of hypnosis operating across space by means of a linking television beam, but it was happening. For Doug Norris, resisting now with new-found knowledge, just dimly sensed the powerful hypnotic order the Raddy's pulsing brain was hurling into his own mind. "You will not send your crude machines down here again to disturb our philosophical reveries!" the Raddy's hypnotic thought was sternly ordering him. "There is no further need. When we read from your minds that it was need for uranium for your primitive power plants that motivated your intrusions here, we gave your brains the post-hypnotic knowledge to improve those power plants so you would not need to come here again. So go, and do not return!" Under that powerful hypnotic command, both Norris and Kincaid turned their Proxies and fled back up the fissure. Not until they had reached Base again, not until they had ripped off the television helmets, did Doug Norris feel that powerful hypnotic command relax. "It's as I suspected!" he cried. "It was the Raddies who put that knowledge in our minds! Who would know nuclear science better than they?" Kincaid stared, his jaw dropping. "Then, to stop our bothering them, they did that by post-hypnotic command working back along our own Proxy-beams?" "Yes!" cried Doug Norris. "Ironic, isn't it? They worked back along our own beams and made Proxies out of _us_!"