As I grew more accustomed to the gloom, I found myself staring at his office chair; once I found myself expecting Abel Slattin to enter the room and occupy it.  There was a little China Buddha upon the bureau in one corner, with a gilded cap upon its head, and as some reflection of the moonlight sought out this little cap, my thoughts grotesquely turned upon the murdered man’s gold tooth.

Vague creakings from within the house, sounds as though of stealthy footsteps upon the stair, set my nerves tingling; but Nayland Smith gave no sign, and I knew that my imagination was magnifying these ordinary night sounds out of all proportion to their actual significance.  Leaves rustled faintly outside the window at my back:  I construed their sibilant whispers into the dreaded name—­Fu-Manchu-Fu-Manchu—­Fu-Manchu!

So wore on the night; and, when the ticking clock hollowly boomed the hour of one, I almost leaped out of my chair, so highly strung were my nerves, and so appallingly did the sudden clangor beat upon them.  Smith, like a man of stone, showed no sign.  He was capable of so subduing his constitutionally high-strung temperament, at times, that temporarily he became immune from human dreads.  On such occasions he would be icily cool amid universal panic; but, his object accomplished, I have seen him in such a state of collapse, that utter nervous exhaustion is the only term by which I can describe it.

Tick-tick-tick-tick went the clock, and, with my heart still thumping noisily in my breast, I began to count the tickings; one, two, three, four, five, and so on to a hundred, and from one hundred to many hundreds.

Then, out from the confusion of minor noises, a new, arresting sound detached itself.  I ceased my counting; no longer I noted the tick-tick of the clock, nor the vague creakings, rustlings and whispers.  I saw Smith, shadowly, raise his hand in warning—­in needless warning, for I was almost holding my breath in an effort of acute listening.

From high up in the house this new sound came from above the topmost room, it seemed, up under the roof; a regular squeaking, oddly familiar, yet elusive.  Upon it followed a very soft and muffled thud; then a metallic sound as of a rusty hinge in motion; then a new silence, pregnant with a thousand possibilities more eerie than any clamor.

My mind was rapidly at work.  Lighting the topmost landing of the house was a sort of glazed trap, evidently set in the floor of a loft-like place extending over the entire building.  Somewhere in the red-tiled roof above, there presumably existed a corresponding skylight or lantern.

So I argued; and, ere I had come to any proper decision, another sound, more intimate, came to interrupt me.

This time I could be in no doubt; some one was lifting the trap above the stairhead—­slowly, cautiously, and all but silently.  Yet to my ears, attuned to trifling disturbances, the trap creaked and groaned noisily.