The whole business was kept at a point approximately 5,100 miles from Earth, where Earth's gravitational attraction approached neutrality and where the entire space-station could be maintained in a given position or moved at will with a minimum expenditure of energy. Technically the station was owned by Night Sun, Inc., along with nearly a hundred others around Earth, and this particular station, No. 18, was under contract to furnish illumination at night over Paris, France, by staying out of Earth's shadow and reflecting sunlight on Paris during the night. Management of such a station involved many mathematical factors in distance, triangulation with Paris, velocity and angulation, and control of the curve of the mirror. Normally this was a parabolic curve, but it was constantly varied with other factors to produce the desired degree of illumination. No. 18 was under the sole control of Dale Stevenson, who had been psych-tested and certified by the United Nations licensing board. That made the Bryd feel a little better. It looked as if he had made a mistake twenty-four years ago, but it also looked as if the licensing board had been fooled within the last year, for Dale certainly was getting ready to cause a lot of trouble in Paris. He could actuate the controls to expand or contract the rim of the station and thus vary the focal length of the sodium lens, and if he should actually concentrate the sun's rays in a small area, he could draw a flaming path of ruin through the center of Paris. Reluctantly the Bryd checked again, and found that that was exactly what Dale Stevenson was about to do. The Bryd wondered why. It groaned. Humans were always up to something. Why couldn't they relax so the Bryd could rest? The Bryd had been so happy back in 2250--or let's see, was it _up_ in 2250? (This was 2045.) That was when Bob What's-his-name and that cute girl had landed on Pluto and given him a chance to get away. The long, lonely eons in Pluto's absolute zero had been quite monotonous to the Bryd, which was nothing but pure energy but which certainly had its feelings. After almost a third of a billion years marooned on Pluto it had sometimes almost wished it had not been so adventurous in its youth and hopped that stray comet as it had swept by its home on Arcturus. For it had tired of the comet and jumped off on Pluto, and then had discovered it didn't have enough range of its own to get from Pluto to another planet. Then it was that Bob and Alys had come along on their 'round-the-system honeymoon, and the Bryd had hitched a ride to Earth (unknown to them), for it was pretty darned lonesome by that time.