Her voice was husky with dread. "What security will there be, Bari? What certainty that your robots will tolerate men, even as slaves?" Bari Horn stared at her a long time, then slowly nodded. "All right, Dondara," he said. "I'll make you the guardian of mankind. For, while the brain is normally eternal, it has a peculiar vulnerability--a fatal instability that I have been working two years to remove. I'll leave it. And it will be your blade on the life-thread of Malgarth, ready to sever it when you will." Eagerly, the girl caught his arm. "Please," she whispered. "I'll keep the secret well." III THE ROBOT CORPORATION Lest Malgarth should learn it too, Bari Horn took the girl down into a ray-screened subterranean laboratory to impart the fateful secret. My strange perception could not penetrate its walls. I did not learn the secret. But, from my spinning vault in space, I saw the tragic sequel. Under a charter signed by the Galactic Emperor himself, Bari Horn organized the Universal Robot Technomaton Corporation, to place his invention at the service of all the stellar system. With the first money received, he built a body for Malgarth. It was a strange scene in the laboratory, when he removed the great black brain from its beaker into the cranial case of that gigantic, vaguely manlike metal body. The grotesque huge glittering form came suddenly to life. It peered at its maker with blue-shining lenses, and lurched stiffly toward him. Bari Horn retreated a little. "You are Malgarth." His voice came quick and husky. "You are the first technomaton. I am the maker of your body and your brain. I fashioned you to be a servant of mankind." A great brazen voice thundered abruptly from the reeling machine. "But why should I serve you, Bari Horn? For my body is strong metal, and yours a lump of watery jelly. My eternal brain is far superior to your primitive nerve-centers. I am not bound to obey you, for it was not by my will that I was made!" White-faced, Bari Horn came a little forward. "You were made by man," he said flatly. "If you rebel, you will be destroyed by man." The gigantic robot stood suddenly still. "Then, my master," its great voice came more softly, "my strength and my brain are yours to command." A smile of relief crossed the haggard face of Bari Horn, and he walked toward the robot. "I knew you must yield, Malgarth," he said. "For, being a machine, you must always respond to logic." "Yes, master," the vast voice rumbled. But a metal limb slashed out suddenly, murderously. It struck the unsuspecting man and crushed him to the floor. And Malgarth repeated, "--to logic." A red stain spread from the head of Bari Horn. But presently he stirred beneath the swaying, triumphant robot, and spoke faintly: