“There’s no doubt in my mind,” said Inspector Bristol, “that your experience was real enough.”

The sun was shining into my room now, but could not wholly disperse the cloud of horror which lay upon it.  That I had been drugged was sufficiently evident from my present condition, and that I had been taken away from my chambers Inspector Bristol had satisfactorily proved by an examination of the soles of my slippers.

“It was a clever trick,” he said.  “God knows what it was they puffed into your face through the letter box, but the devilish arts of ten centuries, we must remember, are at the command of Hassan of Aleppo!  The repetition of the trick at the mysterious place you were taken to is particularly interesting.  I should say you won’t be in a hurry to peer through letter boxes and so forth in the future?”

I shook my aching head.

“That accursed yellow room,” I replied, “stank with the fumes of hashish.  It may have been some preparation of hashish that was used to drug me.”

Bristol stood looking thoughtfully from the window.

“It was a nightmare business, Mr. Cavanagh,” he said; “but it doesn’t advance our inquiry a little bit.  The prophecy of the old man with the white beard—­whom you assure me to be none other than Hassan of Aleppo—­is something we cannot very well act upon.  He clearly believes it himself; for he has released you after having captured you, evidently in order that you may be at liberty to take up your duty as trustee of the slipper again.  If the slipper really comes back to the Museum the fact will show Hassan to be something little short of a magician.  I shan’t envy you then, Mr. Cavanagh, considering that you hold the keys of the case!”

“No,” I replied wearily.  “Poor Professor Deeping thought that he acted in my interests and that my possession of the keys would constitute a safeguard.  He was wrong.  It has plunged me into the very vortex of this ghastly affair.”

“It is maddening,” said Bristol, “to know that Hassan and Company are snugly located somewhere under our very noses, and that all Scotland Yard can find no trace of them.  Then to think that Hassan of Aleppo, apparently by means of some mystical light, has knowledge of the whereabouts of the slipper and consequently of the whereabouts of Earl Dexter (another badly wanted man) is extremely discouraging!  I feel like an amateur; I’m ashamed of myself!”

Bristol departed in a condition of irritable uncertainty.

My head in my hands, I sat for long after his departure, with the phantom characters of the ghoulish drama dancing through my brain.  The distorted yellow dwarfs seemed to gibe apish before me.  Severed hands clenched and unclenched themselves in my face, and gleaming knives flashed across the mental picture.  Predominant over all was the stately figure of Hassan of Aleppo, that benignant, remorseless being, that terrible guardian of the holy relic who directed the