These thoughts just glanced through her mind as lightning glimmers through the thunderous clouds, and, with the sudden instinct of self-preservation, she ran to the door, determined to rush into safety. Before she had reached it, or her hand could touch the lock, a slow and gentle scratching on the window-pane arrested her, and she paused, fascinated, to understand it. Scratch--scratch--scratch--cr-ick! the tiny tinkle of falling glass. Scratch--scratch--scratch--scratch--scratch--scratch! cr-ick--cr-ick! More glass falling, a crunching footstep, a soft tremor of the mahogany shutter! Margaret essayed to wrench round the heavy lock of her door. Her hand had no more strength than an infant's. She shuddered from head to foot. One more desperate wrench! A low snarl reached her ear! Eager paws beat at the bottom of her door! She stood transfixed as the devil's cunning of her adversary dawned upon her mind. The terrible sleuth-hound had been stationed outside her door, ready to tear her limb from limb when she should issue. CHAPTER XIX. A PRAYER TO HEAVEN. The game had passed out of her hands. Should she trust to the blood-thirsty brute, or to the blood-thirsty man? I think she would have thrown herself upon such mercy as the hound would show her, rather than trust to Roland Mortlake. But the time had passed even while she stood in sore doubt. That mysterious tremor of the shutter had ceased, and now, in the ominous stillness, she saw--oh horror! what was that? A small circular hole had been cut in the panel, and through it she caught the glitter of a _human eye_ watching her. The blood curdled in her veins, her hands fell, clasped, before her, she stood, with her head bent forward, and dilated eyes returning that awful stare. No horror, caused by death in any form, could have equaled that caused by the mere stealthy glare of a human eye watching her, gleaming upon her, unaccompanied by the visible face. Suddenly the eye was removed, a sharp click broke the supreme silence, a long, slender tube was thrust half-length through the aperture, and pointed with deliberate aim at her heart. A blind haze came between her and the hideous vision. Quicker than thought she darted to one side, and sank to the floor, almost insensible. Her sight cleared, and she looked for the pointed pistol. It was slowly veering round, to bring her again within range. Her eyes measured the room wildly. The windows commanded every part of it except the two upper corners. She must fly across the room or be shot like a dog. She sprang up and flitted swiftly along the wall, and out of range. Now she was safe for a few seconds. She might crouch upon the carpet and pray a few wild words for safety. The pistol returned to the door and covered it, in case of attempted escape.