Sokolski checked out the master controls on the data board and nodded. He clicked on the talkie. "Let's go," he said, his voice, echoing inside the helmet before being transmitted, sounding distant and hollow. Gaines leading, the cable sliding and coiling snakelike between them, they passed through the doorway, over which huge red letters shouted ANYONE WHO WALKS THROUGH THIS DOOR UNPROTECTED WILL DIE, and clomped down the zigzagging corridor toward the uranium pile that crouched within the heart of the plant. Gaines moaned, "It gets damned hot inside these suits." They had reached the end of the trap, and Sokolski folded a thick mittened hand around one handle on the door to the Hot Room. "Not half so hot as it gets outside it, sweetheart, where we're going." He jerked on the handle and Gaines seized the second handle and added his own strength. The huge door slid unwillingly back. The silent sound of the Hot Room surged out over them--the breathless whisper of chained power struggling to burst its chains. Sokolski checked his neutron tab and his gamma reader and they stepped over the threshold. They leaned into the door until it had slid shut again. "I'll take the servomechs, Bert," piped Gaines, tramping clumsily toward the nearest of the gyro-balanced single-wheeled robots. "You always do, it being the easiest job. Okay, I'll work the board." Gaines nodded, a gesture invisible to his partner. He reached the first servo, a squat, gleaming creature with the symbol M-11 etched across its rotund chest, and deactivated it by the simple expedient of pulling from its socket the line running from the capacitor unit in the lower trunk of its body to the maze of equipment that jammed its enormous chest. The instant M-11 ceased functioning, the other two servomechs were automatically activated to cover that section of the controls with which M-11 was normally integrated. This was overloading their individual capacities, but it was an inherent provision designed to cover the emergency that would follow any accidental deactivation of one of them. It was also the only way in which they could be checked. You couldn't bring them outside to a lab; they were _hot_. After all, they spent their lives under a ceaseless fusillade of neutrons, washed eternally with the deadly radiations pouring incessantly from the pile whose overlords they were. Indeed, next to the pile itself, they were the hottest things in the plant. "Nice job these babies got," commented Gaines as he checked the capacitor circuits. He reactivated the servo and went on to M-19. "If you think it's so great, why don't you volunteer?" countered Sokolski, a trifle sourly. "Incidentally, it's a good thing we came in, Joe. There's half a dozen units here working on reserve transistors."