In toward the narrow opening between the great forts swept our ships, and as they moved slowly inward there flashed a challenging signal of lights from those forts, answered at once by similar signals from our ships. Then we were driving inward, between the towering metal castles on either side, flashing in through the great vibration-wall and into the dying galaxy itself. With generators again humming at high speed our half-hundred ships swept on, into the thronging thousands of dead and dying suns that swarmed before us, inside the colossal protecting shell of the great vibration-wall. All about us now were great hordes of swarming dark-stars that we could but dimly glimpse, as our ships flashed between them, vast throngs of black and burned-out suns that outnumbered the few still flaming stars by hundreds to one. Here and there about us, though, as we swept on, we could make out a red sun or two, some comparatively brilliant and others so dark and far gone that they seemed only like giant cooling embers in the black heavens. Clusters there were, too, of which all but one or two suns would be black and dead, and as we flashed on into the depths of this universe we began to realize at last what tremendous necessity it had been that had sent the serpent-peoples driving out through the limitless void in search of a new universe. Far ahead, though, there loomed before us as we sped on a trio of giant crimson suns more brilliant than any we had yet seen in this dying universe, and which hung at its center, each of them as large as great Canopus itself in our own galaxy. In a great triangle they hung there, two of them much brighter than the other, a mighty triplet of titanic waning suns that seemed like the dying monarchs of the vast and dying realm about them. It was down toward these three great suns that our ships were slanting now, down toward the space at the center of their great triangle, and now we saw that in that space there swung a single mighty world, a dark, immense planet of size inconceivable, almost as large as the three great suns at whose center it turned, and whose light and heat fell perpetually upon it. * * * * *