I was at the end of the avenue of poplars. I was surprised. The avenue seemed short. Somehow it had become shortened; I had not expected to reach the end so soon. And where were the guards in olive uniform? There were none. I turned around and looked back. The slope extended on backwards above me. Indeed I had walked downwards. There were no guards, and the fresh, new building was on the hill behind me. Woleshensky stood on the steps. “Now what do you think of a _t_ dimension,” he called out to me. Woleshensky! And a new building, modern! Vibens’ office was in an old, Victorian building. What was there in common between Vibens and Woleshensky? I drew a deep breath. The comforting realization spread gratefully over me that I was back in my native dimension. The gostak and the war were somewhere else. Here were peace and Woleshensky. I hastened to pour out the story to him. “What does it all mean?” I asked when I was through. “Somehow--vaguely--it seems that it ought to mean something.” “Perhaps,” he said in his kind, sage way, “we really exist in four dimensions. A part of us and our world that we cannot see and are not conscious of, projects on into another dimension; just like the front edges of the books in the bookcase, turned away from us. You know that the section of a conic cut by the _y_ plane looks different than the section of the same conic by the _z_ plane? Perhaps what you saw was our own world and our own selves, intersected by a different set of coordinates. _Relativity_, as I told you in the beginning.” THE END Transcriber’s note: This etext was produced from Amazing Stories, March 1930 (vol. 04, no. 12.). The illustrations have been moved to better fit the story. Obvious errors have been silently corrected in this version, but minor inconsistencies have been retained as printed. The following change as been made: oats _to_ floats