"You know, Rowan, why I came to Brinton, to the swamp, to investigate the rumors we had heard of great bones and skeletons existing in the slime of that swamp. And in the week I spent investigating the morass I found that the rumors had spoken truly, for here and there inside the edges of the morass I found great bone-fragments which could only come from dinosaur skeletons. Then, a week after I had begun my search, the thing happened.
"I was working with my probing-rod, perhaps a mile inside the swamp, when there was a sudden distant crashing of trees and I saw a gigantic, slate-colored bulk rolling across the forest toward me. Before I could recover from my amazement the thing was on me, a great brontosaur ridden by one of the lizard-men—a gigantic dinosaur out of the Mesozoic age, crashing through an Illinois swamp! Before I could gather my stunned wits another had crashed toward me from beyond it, and in an instant I was the prisoner of the lizard-creatures, who fettered my hands and feet, crashed back on the great brontosaurs with me toward that mound at the swamp's center, where there yawned the opening of the great shaft. Up and down that shaft moves the great disk-platform, endlessly, and on it they brought me down to this cavern world, down to this gray city of theirs and into this building. And here, first, I was examined by three of their number who seemed to hold positions of authority among them.
"For hours the three examined me, striving to converse with me in their rasping tones, endeavoring to make plain to me the elementary word-sounds of their strange language. That language, I found, is a phonetic one, but aided by gestures and written diagrams we were able to attain to a rough exchange of ideas. And partly through their own questions, partly through what I had seen in the great cavern outside, I came to understand who and what these enigmatic creatures were, and where they had originated.
"They were beings of an age dead for hundreds of millions of years, I learnt, creatures of the Mesozoic age, that period of the earth's history which we call the age of reptiles. For in that age the races of mammals had hardly begun to arise, and the great and smaller reptiles and lizard-races were the rulers of all earth. And just as man, the creature of dominant intelligence, was to develop later from the races of mammals, so had these lizard-men, the dominant intelligence of their own age, developed from the races of reptiles. They had spread out in great numbers over what is now North America, the most habitable portion of earth during the Mesozoic age. They had built strange cities, had developed their knowledge and science in myriad ways, and had learned how to conquer and subjugate the great reptilian creatures who swarmed then on earth, to make servants of them. The great brontosaurs, more tractable than the rest, they used as mounts and beasts of burden; the fiercer tyrannosaurs and allosaurs were their beasts of war; and on the mighty pterodactyls they soared into the upper air and flitted across earth's surface. Great indeed was their power, and through that power and through their terrible, giant servants they ruled all the habitable parts of earth unquestioningly.
"At last, though, there came that great convulsion of earth which was to mark the end of the Mesozoic age, that vast world-cataclysm in which continents sank beneath the seas and new lands rose from the oceans' depths. In such convulsions and mighty quakes the cities of the lizard-men were shaken down and annihilated, and across all their world was wild confusion. They knew, then, that they must find some other place of refuge or perish, and so they hit upon the plan of descending to one of the great cavernous spaces which lie scores of miles down in earth's interior. They had discovered long before that such great caverns exist inside earth's crust, and so they pierced a shaft down to one of them and descended into it to investigate.
"They found it a place large enough to hold all their numbers, and one quite habitable. It was lit perpetually with crimson light, too, since the molten fires of earth's heart had pressed up close to the walls of the cavern, and through an opening in those walls there poured down eternally a raging Niagara of molten rock and flame, that titanic fall of living fire whose blazing radiance illuminates all this cavern-world. So beneath this fall of fire the lizard-men constructed a canal which conducted it into a great stone basin which lay directly beneath the opening of their shaft in the cavern's roof, and from this basin the molten fires were able to seep gradually into crevices beneath the cavern.
"Naturally, however, an intensely powerful gale of heated air roared up from this molten lake, and by setting a ring of current-projectors around the lake they were able to concentrate the cyclonic power of those winds into a single concentrated air-current roaring straight up and through the shaft, and capable of lifting titanic weights up that shaft, just as a cyclone, which is concentrated wind, will lift and whirl about great buildings. And this terrific, upward-thrusting current they used to lift their great disk-platform up the shaft, arranging the projectors beneath so that the force of the current automatically lessened when the disk reached the top, and allowed it to sink again to the cavern's floor, to the fiery lake, whence it traveled up again, and so on ceaselessly, an automatic, never-stopping lift or platform on which the throngs of the lizard-people and their dinosaur-beasts were able to move down into this cavern world.
"Only a portion of their dinosaur servants did they bring with them, leaving the rest to perish above, whose bones, indeed, I had found in the swamp. When this had been done they closed tightly the opening of the great shaft, above, and dismantled the great ascending and descending disk for which they no longer had need. Then their hordes set to work to build up their cities anew in their new cavern home. Far above them the surface of earth writhed and twisted gigantically, annihilating all the hordes of dinosaurs above, but the cavern world of the lizard-men remained unchanged, as they had foreseen, and in it they lived serenely on.
"When at last the surface of earth quieted once more they could have quitted their underworld and gone back up, but they did not do so, since by then their city was established in the safe, warm world of the mighty cavern and they had no desire to leave it. So in that cavern they lived on, while on the world above the races of mammals rose to replace the great reptiles; until with the passing of ages man rose to dominance over all those races and set his cities where those of the lizard-men had once stood. The mouth of the shaft was hidden and covered by the great swamp, and on all earth none suspected the races who dwelt beneath them.