"It seems strange to you," he said, "but you will see the wisdom of such an apparatus. When a great man dies, a man of mental ability above the rest of us, his brain is removed, especially prepared, and then filed and indexed in a building reserved for that purpose. There are thousands of brains preserved there, and every one of them is available at all times, by means of the brain-reader, to aid us with its knowledge, its experience, its memories. Thus when a man dies among us, his intelligence does not die, but remains as a record for us to consult at will, a record of that man's ideas and achievements." "And while we were unconscious," I broke in, "you used the brain-reader on us? Learned our story, learned why we came here?" "It is so," he said, and his face darkened. "We sought to know who you might be, the first strangers ever to approach us. And from the brain-reader came your amazing tale, and we know all that you came to tell us, concerning that creature of evil you term the Raider. And it is that knowledge that has brought those crowds below to await the decision of the Council." "But the Raider?" I cried. "_What_ is it, Kethra? Do you know?" "I know," he said simply, and a brooding expression dropped on his face. "I know," he repeated, "and all here in Kom know. And that you too may know, who have had dealings with this same Raider, I will relate to you what we do know. Soon the council meets, and you will be questioned further. But now--" He was silent a moment, then spoke in a voice vibrant and low-toned. * * * * * "The history of the Kanlars," he began, "the people of the cylinders, the evil ones whose doom draws near. Know, men of the past, that ages ago, though not so far back as your own time, our people dwelt in four mighty cities, each of which was nearly as large as Kom itself. There was no ice-flood from the north, then, and the country around those cities was green and fair, yet none lived in that country, all preferring the gayer life of the vast towns. Long ago, the people had learned to make their food from the soil direct, as we do today, and so there was no need of tilling the land, or living on it. And so, into the four great cities had drifted all the people in this land. "In each city, the buildings were constructed of a different design. Here in Kom, all of the buildings were cone-shaped, and thus this became known as Kom, the city of cones, and we, the dwellers in it, as the people of the cones. Another city was the city of cubes, another the city of spheres, and still another the city of cylinders.