Overhead, aircraft were buzzing to and fro, flickering swiftly across the sky. They seemed to rise from and alight on the roofs of the cylindrical buildings, so that I could not glimpse their occupants. There were throngs passing us in the street now, without attention, crowds of the armored guards and the white-robed slaves. The street itself was illuminated by glowing bulbs, set on top of metal pillars along the way, which emitted a ruddy, pulsating light. It was the same ruddy light that streamed out of the entrances of the buildings we passed, but how it was produced I could not conjecture. * * * * * My mind swung sharply back to my own predicament, when our captors suddenly halted in the street before a large building that was set some distance back from the street, in a smooth expanse of green lawn. A brief order was given and two of the guards seized me by my shoulders and hustled me toward the building I have spoken of, while the rest marched on down the street toward the gigantic central edifice, taking Lantin with them. I saw him looking back as he went, and would have given much to have been able to call out to him, but my guards gave me no chance to do so, pushing me ahead of them toward the building in front of us. A high-arched entrance cut into the curving wall of the building, which was one of the largest I had yet noted. Through this open door led a broad flight of low steps, but my guards did not enter that way, taking me some distance around the building's side to a smaller door that was set in the wall close to the ground. Pushed ahead of them, I stumbled inside and found myself in a long, smooth-walled corridor, down which we went. There were closed doors here and there along the hall's length, and in front of the last one lounged three or four of the guards, who looked up incuriously as we approached. My captors spoke a few words to these, who nodded, and unlocked the door they guarded. A rough shove sent me staggering through the door, and as I pitched forward on my face, I heard it clang shut behind me. I rose to my feet and looked around. The room itself was quite unremarkable, about twenty feet square, walled with smooth stone, and windowless, being lit by several of the ruddy-glowing bulbs that were set in the ceiling. But the score or more of men who were in the room, and who had started up at my sudden entrance, were of intense interest to me.