"I'm going, now," he shouted. "Going! What do I care for your records and your histories? They are not yet written; if they were I'd change them." He bent over me and snatched from my hand the ring of keys, one of which I had used to unlock the door of the navigating room. I tried to grip him around the legs, but he tore himself loose, laughing insanely in a high-pitched, cackling sound that seemed hardly human. "Farewell!" he called mockingly from the doorway. Then the door slammed, and as I staggered to my feet, I heard the lock click. * * * * * I must have acted then by instinct or inspiration. There was no time to think. It would take him not more than three or four seconds to make his way to the exit, stroll by the guard to the spot where we had found him, and--disappear. By the time I could arouse the crew, and have my orders executed, his time would be up, and--unless the whole affair were some terrible nightmare--he would go hurtling back through time to his own era, armed with a devastating knowledge. There was only one possible means of preventing his escape in time. I ran across the room to the emergency operating controls, cut in the atomic generators with one hand and pulled the Vertical-Ascent lever to Full Power. There was a sudden shriek of air, and my legs almost thrust themselves through my body. Quickly, I pushed the lever back until, with my eye on the altimeter, I held the _Ertak_ at her attained height--something over a mile, as I recall it. Then I pressed the General Attention signal, and snatched up the microphone. Less than a minute later Correy and Hendricks, fellow officers, were in the room and besieging me with solicitous questions. * * * * * It had been my idea, of course, to keep Harbauer from leaving the ship, but it was not so destined. Shiro, the sentry on duty outside the _Ertak_, was the only witness to Harbauer's fate. "I was walking my post, sir," he reported, "watching the sun come up, when suddenly I heard the sound of running feet inside the ship. I turned towards the entrance and drew my pistol, to be in readiness. I saw the stranger we had taken into the ship appear at the exit, which, as you know, was open. "Just as I opened my mouth to command him to halt, the _Ertak_ shot up from the ground at terrific speed. The stranger had been about to leap upon me; indeed, he had discharged some sort of weapon at me, for I heard a crash of sound, and a missile of some kind, as you know, passed through my left arm.