Tavernake had the feelings of a man suddenly sobered as he turned once more into the Adelphi Terrace.  Waiting until no one was in sight, he opened the door of the empty house with the Yale key which he had kept, and carefully closed it.  He struck a match and listened for several minutes intently; not a sound from anywhere.  He moved a few yards further to the bottom of the stairs, and listened again; still silence.  He turned the handle of the ground floor apartment and commenced a fresh search.  Room by room he examined by the light of his rapidly dwindling matches.  This time he meant to leave behind him no possibility of any mistake.  He even measured the depths of the walls for any secret hiding place.  From room to room he passed, leisurely, always on the alert, always listening.  Once, as he opened a door on the third floor there was a soft scurrying as though of a skirt across the floor.  He struck a match quickly, to find a great rat sitting up and looking at him with black, beady eyes.  It was the only sign of life he found in the whole building.

When he had finished his search, he came down to the ground floor and entered the room corresponding with the one from which he had heard voices in the adjoining house.  He crouched here upon the dusty boards for some time, listening.  Now and then he fancied that he could still hear voices on the other side of the wall, but he was never absolutely certain.

At last he rose to stretch himself, and almost as he did so a fresh sound from outside attracted his notice.  A motor-car had turned into the Terrace.  He walked to the uncurtained window and stood there, sure of being himself unseen.  Then his heart gave a great leap.  Unemotional though he was, this was a happening which might well have excited a more phlegmatic individual.  A motor-car which he remembered very well, although it was driven now by a man in dark livery, had stopped at the next house.  A woman and two men had descended.  Tavernake never glanced at the latter; his eyes were fastened upon their companion.  She was wrapped in a long cloak, but she lifted her skirts as she crossed the pavement, and he saw the flash of her silver buckles.  Her carriage, her figure, were unmistakable.  It was Elizabeth who was paying this early morning visit next door!  Already the little party had disappeared.  They did not even ring the bell.  The door must have been opened silently at their coming.  The motor-car glided off.  Once more the Terrace was deserted.

Tavernake felt sure that he knew now the solution,—­there was a way from this house into the next one.  He struck another match and, standing back a few yards, looked critically at the dividing wall.  In ancient days this had evidently been a dwelling-house of importance, elaborately decorated, as the fresco work upon the ceiling still indicated.  The wall had been divided into three panels, with a high wainscoting.  Inch by inch he examined it from one end to the other;