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.

Not content with a casual inspection, he particularly examined those
papers which, in his dream adventure, he had believed to have been
submitted to mysterious inspection. They showed no signs of having
been touched. The casement curtains were drawn across the recess
formed by the French windows, and sunlight streamed in where,
silhouetted against the pallid illumination of the moon, he had seen
the man in the cowl. Drawing back the curtains, he examined the window
fastenings. They were secure. If the window had really been open in
the night, he must have left it so himself.

"Well," muttered Stuart--"of all the amazing nightmares!"

He determined, immediately he had bathed and complete