"There is an entrance to this room leading from the chamber in which the signorina first slept," remarked Paul quietly. This statement was pure conjecture on his part, but its truth was instantly made evident by Lambro's manner. He turned so savagely upon Jacintha that Paul thought he was going to strike her. "So you couldn't keep your tongue quiet?" "You err," said Paul, hastening to vindicate the woman. "Jacintha has told me nothing. It is simply a guess of mine, and--" He broke off abruptly and placed his ear to the door. "By heaven, there is some one in this room. I can detect a sound within. Signorina, are you here?" he cried, rapping upon the panels. The dusk of the landing was suddenly illumined by a light that came and went in a moment. Merely a flash of summer lightning. It was accompanied by something startling within. A faint cry of "Oh!"--plainly the voice of Barbara; a dull thud as of the fall of a human body, and then a significant stillness. With a soldier's promptitude Paul flung himself against the door, bruising his shoulders by the violence of the impact. "You'll never force that door," said Lambro. "It's too strong. We must go downstairs. The signorina must have got in here through the secret panel in the bedroom." Paul darted down the staircase, and in a moment more was within the bedchamber. He saw what had escaped his eye in the three previous explorations, namely, that the circular piece of violet-colored wax was traversed by a horizontal fracture, clearly caused by the moving of the panel. Lambro, who had followed close upon Paul, touched a certain spring hidden within some ornamental carving of the wall, and the panel glided off laterally, revealing a narrow corridor behind. "To the left," said Lambro. "There's a staircase a few feet off. At the top of that another to the right. Mount that and you'll see the Master's room before you." It was strange that the old Palicar did not follow Paul up the staircase, but so it was. He remained in the bedroom by the open panel with his hand to his ear in the attitude of listening. "Oh, if she has discovered--it!" said Jacintha, with clasped hands. "Well, what if she has? It was not our doing, nor the Master's for the matter of that." "When I heard the signorina fall just now it brought the heart to my mouth. It reminded me of that other fall--you know whose. And in the same room, too! If--" "Hold your tongue! How can I listen while you keep chattering?" Paul, following the directions given by Lambro, had ascended the two staircases, and passing through a square opening in a panelled wall similar to that which he had just quitted, found himself in the mysterious study. Barbara lay upon the floor in a seeming swoon. Paul cast one swift glance around the apartment, but failed to discern anything in its present state calculated to inspire fear.