"Thus great Neptune, though farthest of all planets from the sun, became habitable the earliest of all. And since, wherever a world is found on which life is possible, life sooner or later will arise, so it arose on Neptune. Race upon race of living creatures rose upon it, and race after race vanished, annihilated by changing conditions on its surface which they could not withstand. It was not until we disk-bodied Neptunians evolved upon the great world's surface, indeed, that there came a permanent form of life upon it. For we, whose disk-bodies owed their squat, flat shapes to the gravitational power of Neptune, so much greater than that of your inner worlds, had in larger measure that spark of intelligence which the other creatures had lacked. And with that gleam of mind, of intelligence, we were able to withstand the changing conditions on Neptune's surface by adapting ourselves to those conditions, growing ever in numbers and spreading out over our world's surface, until at last we swarmed in millions upon it and were rising into greater and greater comprehension of the universe about us, into greater and greater intelligence and power. * * * * * "Great buildings we built upon Neptune's surface, and deep we tunnelled below its surface, also. Through breaks in the great cloud-screen about our world we looked forth and saw with our instruments the other planets that moved about our sun, and looked forth also into space and saw the hosts of other suns that moved at vast distances from our own. Our eyes were accustomed to the dim Neptunian day, our bodies to its great gravitational power, and it was our home-world. Yet by this time so vast had become our numbers that millions of us were crowded too closely together, and desired to migrate to Triton, our moon, and settle there. And though we had never yet been able to sally forth from the surface of our own great world of Neptune, we found the way to do so then. "That way was given to us by the discovery by our scientists of a new force-vibration, one that lay in wavelength between the light vibrations and the higher electrical vibrations. This force-vibration, they found, exerted a definite pressure or force upon any object struck by its waves, just as the light rays themselves exert a definite, though far smaller, pressure upon whatever matter they strike. With this new force-ray, therefore, we planned to propel vehicles through space, and we constructed great cylindrical vehicles which were to hurtle out into space by generating inside them a great force-ray which would be shot back against a world and thus propel them by repulsion away from that world. These cylinders were made and tested, and since they worked perfectly, we constructed many of them, enough to take out all the millions of our surplus population to Triton. And so in those cylinders those millions of Neptunians went hurtling out to Triton.