"Anyone coming up by way of the fire escape could, of course, have raised the window from the outside, and closed it again after leaving the room," he said, more to himself than to Mrs. Morton. Then he got out on the fire escape and made a careful examination of its surface. "When was this ironwork painted?" he asked Mrs. Morton, through the window. "About ten days ago." "H--m." Duvall examined the newly painted iron surface with rather a blank expression. That anyone had walked upon it since it had received its newly applied coat was, he felt, out of the question. The paint was so new, so shiny, so yielding in its fresh glossiness that, even treading as lightly as he could, the marks of his shoes were plainly visible. He leaned over and pressed the palm of his hand upon the grated iron floor. The pressure of his hand was sufficient to dull the freshly painted surface. It seemed impossible that anyone, even in bare or stockinged feet, could have been upon the fire escape, without having left tell-tale marks upon it. He re-entered the room, and turned his attention to the other window. Here the opportunities for entrance seemed even more unfavorable. The window was situated on the fourth floor. There was still another floor above, with a window similarly located. Anyone might, of course, have been lowered from this window above, to the sill of the one at which he now stood, and entered the room in that way. He examined with care the white woodwork of the window sill, also freshly painted. It showed no marks. This, of course, was not conclusive. He determined to investigate the occupants of the apartment on the top floor. The wall of the brownstone dwelling house next door, which formed the east side of the narrow court, was of brick, covered with ivy. There were no windows in it whatever. Apparently it had once adjoined the wall of a similar house, where the apartment building now stood, and when the second house had been torn down to make way for the new building, the partition wall had remained as originally built, without windows. Duvall examined this house next door with a great deal of interest. It was four stories high, with an attic, and rose to almost the same height as the fifth floor of the apartment house, owing, no doubt, to its ceilings being somewhat higher. In the sloping roof of the attic were three small dormer windows, facing the court, but the nearest one was perhaps twenty feet from the window of Ruth's room, in a horizontal direction, and some eight or ten feet above it. There was no way in which anyone could have passed from the attic window to that of Ruth's room, even supposing such a person to be an expert climber. Anyone lowered from this window by means of a rope would merely have found himself hanging against a bare brick wall, twenty feet from the window of the girl's room. Duvall, accompanied by Mrs. Morton, made his way back to the library. "You feel quite certain about the cook?" he asked.