He switched off the light and walked across to the door. He had actually passed out intending to return to his room, when he became aware of a slight draught. He stopped. Someone or something, evil and watchful, seemed to be very near again. Stuart turned and found himself gazing fearfully in the direction of the open study door. He became persuaded anew that someone was hiding there, and snatching up an ash stick which lay upon a chair in the hall he returned to the door. One step into the room he took and paused--palsied with a sudden fear which exceeded anything he had known. A white casement curtain was drawn across the French windows ... and outlined upon this moon-bright screen he saw a tall figure. It was that of a _cowled man_! Such an apparition would have been sufficiently alarming had the cowl been that of a monk, but the outline of this phantom being suggested that of one of the Misericordia brethren or the costume worn of old by the familiars of the Inquisition! His heart leapt wildly, and seemed to grow still. He sought to cry out in his terror, but only emitted a dry gasping sound. The psychology of panic is obscure and has been but imperfectly explored. The presence of the terrible cowled figure afforded a confirmation of Stuart's theory that he was the victim of a species of waking nightmare. Even as he looked, the shadow of the cowled man moved--and was gone. Stuart ran across the room, jerked open the curtains and stared out across the moon-bathed lawn, its prospect terminated by high privet hedges. One of the French windows was wide open. There was no one on the lawn; there was no sound. "Mrs. M'Gregor swears that I always forget to shut these windows at night!" he muttered. He closed and bolted the window, stood for a moment looking out across the empty lawn, then turned and went out of the room. CHAPTER II THE PIBROCH OF THE M'GREGORS Dr. Stuart awoke in the morning and tried to recall what had occurred during the night. He consulted his watch and found the hour to be six a. m. No one was stirring in the house, and he rose and put on a bath robe. He felt perfectly well and could detect no symptoms of nervous disorder. Bright sunlight was streaming into the room, and he went out on to the landing, fastening the cord of his gown as he descended the stairs. His study door was locked, with the key outside. He remembered having locked it. Opening it, he entered and looked about him. He was vaguely disappointed. Save for the untidy litter of papers upon the table, the study was as he had left it on retiring. If he could believe the evidence of his senses, nothing had been disturbed.