; in fact the effect was that which must have
resulted had the speaker been suddenly stricken down. But the deadly
silence which ensued was instantly interrupted. My heart seemed to
be clutched as though by fingers of ice; a stark and supernatural
horror held me riveted in my chair.

For as though Nayland Smith's words had been heard by the ghostly
inhabitant of Graywater Park, as though the tortured priest sought
once more release from his age-long sufferings--there came echoing,
hollowly and remotely, as if from a subterranean cavern, the sound
of _knocking_.

From whence it actually proceeded I was wholly unable to determine.
At one time it seemed to surround us, as though not one but a hundred
prisoners were beating upon the paneled walls of the huge, ancient
apartment.

Faintly, so faintly, that I could not be sure if I heard aright,
there came, too, a stifled cry. Louder grew the the frantic beating
and louder ... then it ceased abruptly.

"Merciful God!" I whispered--"what was it? What was it?"

CHAPTER XXXV

THE EAST TOWER

With a cigarette between my lips I sat at the open window, looking
out upon the skeleton trees of the orchard; for the buds of early
spring were only just beginning to proclaim themselves.

The idea of sleep was far from my mind. The attractive modern
furniture of the room could not deprive the paneled walls of the musty
antiquity which was their birthright. This solitary window deeply set
and overlooking the orchard upon which the secret stair was said to
open, struck a note of more remote antiquity, casting back beyond the
carousing days of the Stuart monarchs to the troublous time of the
Middle Ages.

An air of ghostly evil had seemed to arise like a miasma within the
house from the moment that we had been disturbed by the unaccountable
rapping. It was at a late hour that we had separated, and none of us,
I think, welcomed the breaking up of our little party. Mrs. Oram, the
housekeeper, had been closely questioned by Smith--for Homopoulo, as a
new-comer, could not be expected to know anything of the history of
Graywater Park. The old lady admitted the existence of the tradition
which Nayland Smith had in some way unearthed, but assured us that
never, in her time, had the uneasy spirit declared himself. She was
ignorant (or, like the excellent retainer that she was, professed to
be ignorant) of the location of the historic chamber and staircase.

As for Homopoulo, hith