Vaajo chuckled. "So. You saw last night's display, felt a taste of it perhaps, and you have guessed. Yes, your surmise is correct! We utilize the Rajec caravans. Two hundred yesterday, and fine specimens they were! But they are now mere walking hulks, devoid of all but the most meager mental impulses. Their bodies will be sent north to work the Uranium pits. Their minds have already been absorbed into my--shall we say, weapon, increasing its potential considerably." Ketrik's brain seemed to twist inside his skull, until he could not tell whether he felt horror or fury or both. He only knew he must keep control, learn more of this grisly thing that Vaajo was conducting with human minds.... He found his own voice, hard and dry, saying, "Yes, I saw it last night, felt it ... but still I cannot understand...." He passed a hand across his forehead in seeming bewilderment. He heard Vaajo saying, "It cannot matter now, for my beam reached Earth last night ... yes, it would please me to tell you something of it! You must have heard of the ancient city of M'Tonak, lying far beneath Mars' Polar Cap. And the sentient thought-force that came from outer space, or another dimension--no one ever knew--to land at M'Tonak where it remained for untold centuries. Through all that time the Entity remained barely alive, unknown to man, sustaining itself by sending out invisible radiations that fed on Martian minds! And you must have heard of the Earthman, Jim Landor, who found his way there and destroyed the Entity, leaving it crushed beneath tons of ice. All this was before your time or mine. Over a hundred years ago...."[3] [Footnote 3: _City of the Living Flame_, Planet Stories, Fall, 1942.] Ketrik nodded. He had heard the story many times. * * * * * Dar Vaajo went on. "The story of the thought-entity beneath our ice cap had always intrigued me," he said. "So several years ago I sent some workmen to uncover that ancient city. Yes, you have guessed. The Entity hadn't died! It remained there insentient but alive, frozen into suspended animation beneath miles of ice! It was then that I remembered the stories of its power, its insatiable appetite for the mental forces of man ... and thereupon I evolved my scheme. It has been dangerous, Ketrik, but I worked slowly and carefully. "The first step was to waken it, which was easy. The second step was to keep it under control--not so easy. But I managed this by means of Uranium rays which seems to be the only thing capable of combating the Entity's own peculiar atomic structure. That was the reason for my Uranium embargo; I've had to increase the potential of these controlling rays as the Entity grew in size and power." "You mean you ... _fed it_? Allowed it to _grow_?" Ketrik was aghast, listening to this cold-blooded recital. "Of course! How else was I to reach Earth with it, across miles of space? That was my ultimate goal."