He dropped into the darkness on the other side without any discomfort to himself, and made his cautious way towards the house. Dogs were the danger, but apparently Mrs. Rider did not keep dogs, and his progress was unchallenged.
He saw no light either in the upper or lower windows until he got to the back. Here was a pillared-porch, above which had been built what appeared to be a conservatory. Beneath the porch was a door and a barred window, but it was from the conservatory above that a faint light emanated. He looked round for a ladder without success. But the portico presented no more difficulties than the wall had done. By stepping on to the window-sill and steadying himself against one of the pillars, he could reach an iron stanchion, which had evidently been placed to support the framework of the superstructure. From here to the parapet of the conservatory itself was but a swing. This glass-house had casement windows, one of which was open, and he leaned on his elbows and cautiously intruded his head.
The place was empty. The light came from an inner room opening into the glass sheltered balcony. Quickly he slipped through the windows and crouched under the shadow of a big oleander. The atmosphere of the conservatory was close and the smell was earthy. He judged from the hot-water pipes which his groping hands felt that it was a tiny winter garden erected by the owner of the house for her enjoyment in the dark, cold days. French windows admitted to the inner room, and, peering through the casement curtains which covered them, Tarling saw Mrs. Rider. She was sitting at a desk, a pen in her hand, her chin on her finger-tips. She was not writing, but staring blankly at the wall, as though she were at a loss for what to say.
The light came from a big alabaster bowl hanging a foot below the ceiling level, and it gave the detective an opportunity of making a swift examination. The room was furnished simply if in perfect taste, and had the appearance of a study. Beside her desk was a green safe, half let into the wall and half exposed. There were a few prints hanging on the walls, a chair or two, a couch half hidden from the detective's view, and that was all. He had expected to see Odette Rider with her mother, and was disappointed. Not only was Mrs. Rider alone, but she conveyed the impression that she was practically alone in the house.