"With that done, with the great generators ready, the ray-mechanism or opening ready, and the control-boxes and their intricate controls all completed, the first step was finished and there remained but to turn on the giant ray, to send it forth to that bright star in Sagittarius. So on the day that had been designated, the Neptunians to whom had been entrusted the all-important watch of the twenty controls, took their places in the control-boxes. The great ray-mechanism had been so placed in Triton's dark side, of course, that it pointed directly toward that star which the ray was to strike, and so it was needed only to turn on the giant ray. And so, at last, with all the Neptunians gathered there beneath the roof around the walls of the giant pit, staring through those walls, transparent from within, we gave the word. Then, as one, the twenty controls were opened, and from the gathered throbbing generators from the great ray-mechanism at the huge pit's bottom, there drove upward and outward into the great void of space the colossal force-ray, visible only near its source as pale light, flashing out at almost the speed of light itself, on its stupendous journey across the void toward that bright star in Sagittarius that was its goal! "There was no push against Triton, of course, when that colossal ray went forth, for there could be no push against Triton until that ray struck a solid body, struck the star that was its goal, and then it would push back against Triton. Just as if you reach forth to push yourself away from a wall, there is no push on your body until your hand reaches the wall. Not until dozens of years had passed, we knew, would that great ray strike the star in Sagittarius that was its goal, and not until then would come the back-push against Triton, the bracing back-push that was its purpose. And in those dozens of years, with the great ray shot ceaselessly forth to that star, of course, Neptune and Triton themselves would be moving somewhat, would be moving as Neptune followed its slow orbit around the sun. But so slow and so vast is Neptune's orbit-movement, that it would have moved but little, and as it moved, the ray-mechanism would be turned constantly a very little so that its great ray would still be directed ceaselessly toward the star in Sagittarius, and so that when that ray struck that star, Neptune and Triton would be just between or in line with the sun and that distant star.