In a hospital in Vienna, in a room where sunlight flooded through ultraviolet permeable crystal, the warm rays struck upon smooth walls the color of which changed from hot reds to cool yellow or gray or to soothing green, as the Directing Surgeon might order. An elusive blending of tones now seemed pulsing with life; surely even a flickering flame of vitality would be blown into warm livingness in such a place.Even the chart case in the wall glittered with the same clean, brilliant hues from its glass and metal door. The usual revolving paper disks showed white beyond the glass. They were moving; and the ink lines grew to tell a story of temperature and respiration and of every heart-beat.On the identification-plate a name appeared and a date: "Chet Bullard-23years. Admitted: August 10, 1973." And below that the ever-changing presentticked into the past in silent minutes: "August 15, 1973; World StandardTime: 10:38-10:39-10:40-"For five days the minutes had trickled into a rivulet of time that flowed past a bandaged figure in the bed below-a silent figure and unmoving, as one for whom time has ceased. But the surgeons of the Allied Hospital at Vienna are clever.10:41-10:42-The bandaged figure stirred uneasily on a snow-white bed... .A nurse was beside him in an instant. Was her patient about to recover consciousness? She examined the bandages that covered a ragged wound in his side, where all seemed satisfactory. To all appearances the man who had moved was unconscious still; the nurse could not know of the thought impressions, blurred at first, then gradually clearing, that were flashing through his mind.Flashing; yet, to the man who struggled to comprehend them, they passed laggingly in review: one picture followed another with exasperating slowness... .Where was he? What had happened? He was hardly conscious of his ownidentity... .There was a ship ... he held the controls ... they were flying low... . One hand reached fumblingly beneath the soft coverlet to search for a triple star that should be upon his jacket. A triple star: the insignia of a Master Pilot of the World!-and with the movement there came clearly a realization of himself.Chet Bullard, Master Pilot; he was Chet Bullard ... and a wall of water was sweeping under him from the ocean to wipe out the great Harkness Terminal buildings... . It was Harkness-Walt Harkness-from whom he had snatched the controls... . To fly to the Dark Moon, of course-What nonsense was that?... No, it was true: the Dark Moon had raised the devil with things on Earth... . How slowly the thoughts came! Why couldn't he remember?...Dark Moon!-and they were flying through space... . They had conquered space; they were landing on the Dark Moon that was brilliantly alight. Walt Harkness had set the ship down beautifully-Then, crowding upon one another in breath-taking haste, came clear recollection of past adventures: They were upon the Dark Moon-and there was the girl, Diane. They must save Diane. Harkness had gone for the ship. A savage, half-human shape was raising a hairy arm to drive a spear toward Diane, and he, Chet, was leaping before her. He felt again the lancet-pain of that blade... .And now he was dying-yes, he remembered it now-dying in the night on a great, sweeping surface of frozen lava... . It was only a moment before that he had opened his eyes to see Harkness' strained face and the agonized look of Diane as the two leaned above him... . But now he felt stronger. He must see them again... .He opened his eyes for another look at his companions-and, instead of black, star-pricked night on a distant globe, there was dazzling sunlight. No desolate lava-flow, this; no thousand fires that flared and smoked from their fumeroles in the dark.