There was no chance for resistance on the creature's part. For even as we knocked it sidewise with the force of our leap Marlin had grasped the creature's limbs and with fierce, desperate strength I had with my clenched fist closed its mouth-opening in that method whose deadliness had been proved to me in our other battle. The thing threshed wildly, then it, too, had gone limp, and had collapsed. And in the next instant Marlin and I were rising from it, were leaping across the compartment toward the open low door of the nearest great cylinder, from whose great gleaming upright bulk before us came the throbbing of its powerful generators. And then, a dozen feet from it, we stopped dead, and from Marlin came a hoarse cry.

For at that moment there had swept over us, through us, past us, from the direction of Triton's sunward side across its surface, a band of intensely brilliant white light, white light that blazed brilliant for the moment all around us, turning the changeless night of Triton's dark side around us for the moment into a white and blinding day, and then sweeping swiftly on, around Triton's surface! It was the great signal of awakening, the signal for the millions of sleeping Neptunians about us to awake and change places with the swarming millions upon the sunward side! And even as that dazzling signal came, as Marlin and I stood stupefied there for the moment before the looming cylinder's open door, there came from all around us, from over all the dark side's great extent and from all its maze of sleep-compartments, a rising babel of staccato voices, the voices of its awakening Neptunian millions! Then, before ever we could recover from the stupefaction that in that instant held us rooted to the spot, there had poured into the great landing-compartment from the compartments on all sides of it swarms of hastening Neptunians, swarms of disk-bodied monsters, who in that moment saw us, uttered as one a sharp great cry of discovery, and in the next moment were rushing from all sides toward us!

"The cylinder!"

It was Marlin's wild cry, that aroused me from the stupefaction of amazement that held me. Straight before us, a dozen feet away, was the open door of the nearest cylinder, and in the next split-second Marlin and I, as one, had leaped toward it, had shot through that door, into the cylinder's interior, even as the Neptunians raced toward us. The next instant I had reached frantically for the door, had with one swift motion slid it clanging shut, and then as the Neptunian masses outside hurled themselves toward it, Marlin and I were throwing ourselves up through the openings toward the cylinder's uppermost section. In one leap I was at the central control-standard, fumbled frantically with the green control-studs for an agonizing moment, and then, just as we heard the Neptunians below flinging themselves against the door, the great throbbing cylinder shot upward!

Up over Triton's dark side we rose, a dozen slender force-rays criss-crossing about us from beneath in that moment, and as we glanced momentarily down we could see the Neptunians in the landing-compartment beneath rushing toward the other cylinders there! And glancing far across the surface of Triton, we could see all its mighty compartment-city, dark and sunward sides alike, swarming now with Neptunian hordes as the end and beginning of their strange day and night periods was signalled. Over the great compartment-city, over all the countless millions of Neptunians that swarmed through it, there was spreading a crackling roar of excited tumult, as our escape was discovered. And from far away on either side and from beneath us, scores of great cylinders whirled toward us!

"Up—up!" Marlin was shouting now beside me. "They'll have us in another moment!"

I pressed swiftly again the studs before me, and as the cylinder shot up and sidewise with terrific speed on an upward slant I shouted back to Marlin over the roar of air about us. "The roof-openings!" I cried. "We'll make for the nearest one!"

But as the cylinder flashed obliquely upward, Marlin and I crouching in the two opposite seats at the control-standard, I became aware of the swarms of racing cylinders behind closing in upon us. And over the dark and sunward surfaces of Triton that great mounting roar of sound was spreading, as the Neptunian hordes saw our wild attempt at escape. Up—up—and now we were racing close beneath the great roof, transparent from below, with the pursuing cylinders drawing ever nearer, their Neptunian occupants more skilled than I in their operation. And now, too, from those uprising, pursuing swarms were directed toward us slender pencil-like rays of pale light, visible only near their source, concentrated force-rays, that would cleave through our cylinder as through paper!

On and upward—and now as we shot on, with the swarming cylinders hurtling hotly after us in wild pursuit, with the throb of our generators and the roar of air about us thundering in our ears, with the wild tumult of the massed Neptunians on Triton's surface coming dully up to us from beneath, Marlin and I were gazing with tense eyes ahead and upward. The great opening, the great sliding section of the roof down through which we had come—that was our one chance to escape from Triton. I knew that unless we could win through that opening, out of Triton's enclosed world, we were doomed. On and on we went—our eyes still upon the vast roof overhead in search of that opening in it, when suddenly Marlin cried hoarsely in my ear, and pointed ahead. And there from ahead were rushing toward us other scores of cylinders, other swarms of racing cylinders answering the spreading alarm, while still others were shooting up from below toward us! From behind, from ahead, from beneath, the cylinders' swarms were converging upon us in that moment, and as instinctively I slowed our cylinder's mad rush I looked upward, toward the great roof——

"The opening-section!" I cried suddenly. "But it's closed against us!"