"I blamed human beings. Because I did not believe--well, I just said it." "Quite logical, too," said Narina quietly. "Even the machines we made could not use better logic than this," he told her. "Naturally. We have brains--_Brains!_" Narina looked at him with a startled light in her eyes. He nodded soberly. "Brains," he said, "cerebration being nothing more than an application of logic. Narina, we have built the first mechanical brain." "Which is thinking for itself." * * * * * Vinson looked around the plane wildly. "And here we sit in a machine--surrounded by the--enemy." "Escape," said Narina bitterly. "The one thing we did not do!" "Oh, I don't know," he said, waving the cube of metal with its trailing wires. "We have removed its communicating factor. This is--a dead and insensate machine now." He looked around once more. "Come to think of it, it was almost too easy. Now I know why." "Why?" Vinson's face soured. "Remember that in the so-called memory files of the logic computer is every bit of fact and knowledge that mankind could introduce in years of recording. That, Narina, makes the machine more learned, better equipped with knowledge, that any group of men on earth. It could have forestalled us--had it been able at the time!" "During the period it was being transported in sections?" she said quizzically. He nodded. "We took the guts out of this thing just in time. Now--" "Dare we go back?" she whispered. "Dare we approach another machine--any kind of machine?" Vinson hefted the block of metal. "I don't know," he said soberly. "It depends purely on how many of these damned things the machine-brain has manufactured and in what equipment it has them installed. However," he added with clenched teeth, "we can not sit here and wait for the end. We'll fly--and we'll avoid all machinery as long as we can. No radio, no radar, nothing. We fly it blind back to Washington and report to Secretary Hegeman--if we make it." He went to the pilot's compartment and started the engines. The flying boat took off after a short run, and Vinson turned its nose towards Washington. Narina closed her eyes, and almost instantly it seemed as if she were back in the cabin, helpless again. She was reaching for the microphone to call for help. Narina spoke desperately into the microphone, not daring to look up. She sensed rather than saw the monstrous metal hand reaching for her.... [Illustration: _Narina spoke desperately into the microphone, not daring to look up. She sensed, rather than saw the metal hand reaching for her...._] * * * * * The radar screen in General Lloyd's command aircraft showed target traces at extreme range. The radar officer looked startled--then went into swift action. He pressed the key that sent out the identification code and the identification went to the distant fleet of aircraft but was not returned.