Dirk Vanderpool had been sitting alone on the broad terrace of his apartment that occupied the upper stories of the great Gotham Gardens Building when he saw that streak of fire slip down against the darkness of the night. For a moment he, too, had believed that he was watching a meteor, but, when he saw it come to a slow stop and hang stationary in the heavens, he rose to his feet with an exclamation of surprise. For a while he gazed upward with an expression of astonishment on his face and then he turned as he heard someone walking softly in his direction. It was Barstowe, his valet, and the eyes of the man were alive with fear. "What is that thing, Mr. Vanderpool?" he asked in a voice that trembled with alarm. Barstowe was a man of middle age, diminutive in size, and he had the appearance of being nearly petrified with terror. "They are saying over the televisor that--" "What are they saying about it?" asked Dirk somewhat impatiently. "That no one can explain what it is," continued Barstowe. "It must be something terrible, Mr. Vanderpool." "Wheel out the luciscope," ordered Dirk. * * * * * Barstowe disappeared into the apartment and returned with a cabinet that was mounted on small, rubber-tired wheels. The top of it was formed of a metallic frame in which a heavy, circular, concave glass was fitted. The frame was hinged in front so that it could be raised from the rear and adjusted to any angle necessary to catch the light rays from any distant object. Within the cabinet the rays passed through an electrical device that amplified them millions of times, thus giving a clear, telescopic vision of the object on which the luciscope was focused. This instrument, years before, had supplanted entirely the old-fashioned telescopes which not only had been immense and unwieldly but which also had a very limited range of vision. Dirk adjusted the light-converger so that it caught the rays that were being emanated by the weird and shimmering mass that was suspended almost directly above the lofty terrace on which he was standing. Then he switched on the current and glanced into the eye-piece of the apparatus. For several moments he remained silent, studying the image that was etched so vividly on the ground-glass within the luciscope. "It is a queer thing, there is no doubt about that," he confessed when finally he raised his head. "It resembles a gigantic Zeppelin in shape but it does not seem to have any undercarriage or, as far as I can see, any indication of propellers or portholes. I would say, though, Barstowe, that it might be a ship from some other planet if it wasn't for the fact that it seems to be in an almost molten state." * * * * * Dirk again looked into the luciscope and then he made a few adjustments with a thumb-screw that projected from the side of the apparatus.