"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 murderous operations. earl dexter, the stetson man, with his tightly bandaged arm, his gaunt, clean-shaven face and daredevil smile, figured, too, in my feverish daydream; nor was that other character missing, the girl with the violet eyes whose beautiful presence i had come to dread; for like a sybil announcing destruction her appearances in the drama had almost invariably presaged fresh tragedies. i recalled my previous meetings with this woman of mystery. i recalled my many surmises regarding her real identity and association with the case. i wondered why in the not very distant past i had promised to keep silent respecting her; i wondered why up to that present moment, knowing beyond doubt that her activities were inimical to my interests, were criminal, i had observed that foolish pledge.

and now my door-bell was ringing—as intuitively i had anticipated. so certain was i of the identity of my visitor that as i walked along the passage i was endeavouring to make up my mind how i should act, how i should receive her.

i opened the door; and there, wearing european garments but a green turban ... stood hassan of aleppo!

when i say that amazement robbed me of the power to speak, to move, almost to think, i doubt not you will credit me. indeed, i felt that modern london was crumbling about me and that i was become involved in the fantastic mazes of one of those oriental intrigues such as figure in the romance of abu zeyd, or with which most european readers have been rendered familiar by the glowing pages of "the thousand and one nights."

"effendim," said my visitor, "do not hesitate to act as i direct!"

in his gloved hand he carried what appeared to be an ebony cane. he raised and pointed it directly at me. i perceived that it was, in fact, a hollow tube.

"death is in my hand," he continued; "enter slowly and i will follow you."

still the sense of unreality held me thralled and my brain refused me service. like an hypnotic subject i walked back to my study, followed by my terrible visitor, who reclosed the door behind him.

he sat facing me across my littered table with the mysterious tube held loosely in his grasp.

how infinitely more terrifying are perils unknown than those known and appreciated! had a european armed with a pistol attempted a similar act of coercion, i cannot doubt that i should have put up some sort of fight; had he sat before me now as hassan of aleppo sat, with a comprehensible weapon thus laid upon his knees, i should have taken my chance, should have attacked him with the lamp, with a chair, with anything that came to my hand.

but before this awful, mysterious being who was turning my life into channels unsuspected, before that black tube with its unknown potentialities, i sat in a kind of passive panic which i cannot attempt to describe, which i had never experienced before and have never known since.

"there is one about to visit you," he said, "whom you know, whom i think you expect. for it is written that she shall come and such events cast a shadow before them. i, too, shall be present at your meeting!"

his eagle eyes opened widely; they burned with fanaticism.

"already she is here!" he resumed suddenly, and bent as one listening. "she comes under the archway; she crossed the courtyard—and is upon the stair! admit her, effendim; i shall be close behind you!"

the door-bell rang.

with the consciousness that the black tube was directed toward the back of my head, i went and opened the door. my mind was at work again, and busy with plans to terminate this impossible situation.

on the landing stood a girl wearing a simple white frock which fitted her graceful figure perfectly. a white straw hat, of the new york tourist type, with a long veil draped from the back suited her delicate beauty very well. the red mouth drooped a little at the corners, but the big violet eyes, like lamps of the soul, seemed afire with mystic light.

"mr. cavanagh," she said, very calmly and deliberately, "there is only one way now to end all this trouble. i come from the man who can return the slipper to where it belongs; but he wants his price!"

her quiet speech served completely to restore my mental balance, and i noted with admiration that her words were so chosen as to commit her in no way. she knew quite well that thus far she might appear in the matter with impunity, and she clearly was determined to say nothing that could imperil her.

"will you please come in?" i said quietly—and stood aside to admit her.

exhibiting wonderful composure, she entered—and there, in the badly lighted hallway came face to face with my other visitor!

it was a situation so dramatic as to seem unreal.

away from that tall figure retreated the girl with the violet eyes—and away—until she stood with her back to the wall. even in the gloom i could see that her composure was deserting her; her beautiful face was pallid.

"oh, god!" she whispered, all but inaudible—"you!"

hassan, grasping the black rod in his hand, signed to her to enter the study. she stood quite near to me, with her eyes fixed upon him. i bent closer to her.

"my revolver—in left-hand table drawer," i breathed in her ear. "get it. he is watching me!"

i could not tell if my words had been understood, for, never taking her gaze from the sheikh of the assassins, she sidled into the study. i followed her; and hassan came last of all. just within the doorway he stood, confronting us.

"you have come," he said, addressing the girl and speaking in perfect english but with a marked accent, "to open your impudent negotiations through mr. cavanagh for the return of the thrice holy relic to the museum! your companion, the man, who is inspired by the evil one, has even dared to demand ransom for the slipper from me!"

hassan was majestic in his wrath; but his eyes were black with venomous hatred.

"he has suffered the penalty which the koran lays down; he has lost his right hand. but the lord of all evil protects him, else ere this he had lost his life! move no closer to that table!"

i started. either hassan of aleppo was omniscient or he had overheard my whispered words!

"easily i could slay you where you stand!" he continued. "but to do so would profit me nothing. this meeting has been revealed to me. last night i witnessed it as i slept. also it has been revealed to me by erroohanee, in the mirror of ink, that the slipper of the prophet, salla-'llahu 'ale yhi wasellem! shall indeed return to that place accursed, that infidel eyes may look upon it! it is the will of allah, whose name be exalted, that i hold my hand, but it is also his will that i be here, at whatever danger to my worthless body."

he turned his blazing eyes upon me.

"to-morrow, ere noon," he said, "the slipper will again be in the museum from which the man of evil stole it. so it is written; obscure are the ways. we met last night, you and i, but at that time much was dark to me that now is light. the holy 'alee spoke to me in a vision, saying: 'there are two keys to the case in which it will be locked. secure one, leaving the other with him who holds it! let him swear to be secret. this shall be the price of his life!'"

the black tube was pointed directly at my forehead.

"effendim," concluded the speaker, "place in my hand the key of the case in the antiquarian museum!"

hands convulsively clenched, the girl was looking from me to hassan. my throat felt parched, but i forced speech to my lips.

"your omniscience fails you," i said. "both keys are at my bank!"

blacker grew the fierce eyes—and blacker. i gave myself up for lost; i awaited death—death by some awful, unique means—with what courage i could muster.

from the court below came the sound of voices, the voices of passers-by who so little suspected what was happening near to them that had someone told them they certainly had refused to credit it. the noise of busy fleet street came drumming under the archway, too.

then, above all, another sound became audible. to this day i find myself unable to define it; but it resembled the note of a silver bell.

clearly it was a signal; for, hearing it, hassan dropped the tube and glanced toward the open window.

in that instant i sprang upon him!

that i had to deal with a fanatic, a dangerous madman, i knew; that it was his life or mine, i was fully convinced. i struck out then and caught him fairly over the heart. he reeled back, and i made a wild clutch for the damnable tube, horrid, unreasoning fear of which thus far had held me inert.

i heard the girl scream affrightedly, and i knew, and felt my heart chill to know, that the tube had been wrenched from my hand! hassan of aleppo, old man that he appeared, had the strength of a tiger. he recovered himself and hurled me from him so that i came to the floor crashingly half under my writing-table!

something he cried back at me, furiously—and like an enraged animal, his teeth gleaming out from his beard, he darted from the room. the front door banged loudly.

shaken and quivering, i got upon my feet. on the threshold, in a state of pitiable hesitancy, stood the pale, beautiful accomplice of earl dexter. one quick glance she flashed at me, then turned and ran!

again the door slammed. i ran to the window, looking out into the court. the girl came hurrying down the steps, and with never a backward glance ran on and was lost to view in one of the passages opening riverward.

out under the arch, statelily passed a tall figure—and inspector bristol was entering! i saw the detective glance aside as the two all but met. he stood still, and looked back!

"bristol!" i cried, and waved my arms frantically.

"stop him! stop him! it's hassan of aleppo!"

bristol was not the only one to hear my wild cry—not the only one to dash back under the arch and out into fleet street.

but hassan of aleppo was gone!