Queer construction indeed! The quadrangular building completely inclosed this inner yard. At the basement level it was all normal enough. Windows and doors opening from what seemed engine rooms; the kitchen; the laundry. And at this first story it was normal also. These windows through which we were looking; and other windows and occasional balconies in each of the wings. But above this first story there were three others and then the flat roof above them. And in these three upper floors so far as I could see there was not a window! Nothing but the sheer, blank stone walls! "What would you make of that, Ed? Crazy architecture--they said that when the place was built. There are no courtyard rooms at all in the upstairs floors--nearly half the building goes to waste. Turber designed it--" "But what did he say?" "Nothing much, I fancy. It was his own business. Perhaps, merely that he could afford the luxury of all outside rooms for his patients. And look at that inner building--" * * * * * The courtyard was perhaps two hundred feet long, by half as wide. In its center was an oblong brick building, a hundred feet by sixty possibly--and not quite as high as the roof of the main structure. From the angle at which we were gazing, I could see the full front face of this smaller building, and part of one of its ends. It had not a window! Nor a door, except one, very small, at the ground in the center of the front! "Turber's laboratory," said Alan. "At least, that's what it's supposed to be. That one door--nothing else. It's always locked. Nobody has even been in there but Turber, and his Indian assistant. Father once talked with the builders of this place, Ed. That laboratory is nothing but two small rooms at the ground level here in front. All the rest is just four solid brick walls inclosing an inner empty space! What's it for? Nobody knows. But people talk. You can't stop them. Turber's employees here. And most of all, his patients--not quite sane. They talk--of ghosts--things mysteriously going on inside those walls--" People--not quite sane--talking of things unknowable. But I was wholly sane; and as I stood there, gazing at the shadows of twilight gathering in this inner courtyard; the blank upper walls of the large building turning dark with night; the smaller one, standing blank and silent in the courtyard--the whole place seemed suddenly ominous, sinister! * * * * * A step sounded in the room behind us. I started violently; I had not realized how taut were my nerves. We dropped the portieres hastily, and left the window. Turber? But it was not he. A young man stood before us. He was dressed in flannels and a shirt open at the throat. He carried a tennis racket. "Well," said Alan. "How are you, Charlie? Been playing tennis? You remember me, don't you?" A good-looking young fellow. He said: "Do I? You were here once before, weren't you? I saw you in here with Dr. Turber."