on quitting the singular oriental club, harley had first raced off to a public telephone, where he had spoken for some time—as i now divined—to scotland yard. for when we presently arrived at the headquarters of the metropolitan police, i was surprised to find inspector wessex awaiting us. leaning out of the cab window:

“yes?” called harley excitedly. “was i right?”

“you were, mr. harley,” answered wessex, who seemed to be no less excited than my companion. “i got the man's reply an hour ago.”

“i knew it!” said harley shortly. “get in, wessex; we haven't a minute to waste.”

the inspector joined us in the cab, having first given instructions to the chauffeur. as we set out once more:

“you have had very little time to make the necessary arrangements,” continued my friend.

“time enough,” replied wessex. “they will not be expecting us.”

“i'm not so sure of it. one of the biggest villains in the civilized world recognized me three minutes before i called you up and then made good his escape. however, there is at least a fighting chance.”

little more was said from that moment until the end of the drive, both my companions seeming to be consumed by an intense eagerness to reach our destination. at last the cab drew up in a deserted street. i had rather lost my bearings; but i knew that we were once more somewhere in the chinatown area, and:

“follow us until we get into the house,” harley said to inspector wessex, “and wait out of sight. if you hear me blow this whistle, bring up the men you have posted—as quick as you like! but make it your particular business to see that no one gets out!”

into a pitch-dark yard we turned, and i felt a shudder of apprehension upon observing that it was the entrance to a wharf. dully gleaming in the moonlight, the thames, that grave of many a ghastly secret, flowed beneath us. emerging from the shadow of the archway, we paused before a door in the wall on our left.

at that moment something gleamed through the air, whizzed past my ear, and fell with a metallic jingle on the stones!

instinctively we both looked up.

at an unlighted window on the first floor i caught a fleeting glimpse of a dark face.

“you were right!” i said. “ali of cairo has forestalled us!”

harley stooped and picked up a knife with a broad and very curious blade. he slipped it into his pocket, nonchalantly.

“all evidence!” he said. “keep in the shadow and bend down. i am going to stand on your shoulders and get into that window!”

wondering at his daring, i nevertheless obeyed; and harley succeeded, although not without difficulty, in achieving his purpose. a moment after he had disappeared in the blackness of the room above.

“stand clear, knox!” i heard.

two of the cushion seats sometimes called “poof-ottomans” were thrown down, and:

“up you come!” called harley. “i'll grasp your hands if you can reach.”

it proved no easy task, but i finally managed to scramble up beside my friend—to find myself in a dark and stuffy little room.

“this way!” said harley rapidly—“upstairs.”

he led the way without more ado, but it was with serious misgivings that i stumbled up a darkened stair in the rear of my greatly daring friend.

a pistol cracked in the darkness—and my fez was no longer on my head!

harley's repeater answered, and we stumbled through a heavily curtained door into a heated room, the air of which was laden with some eastern perfume. in the dim light from a silken-shaded lantern a figure showed, momentarily, darting across the place before us.

again harley's pistol spoke, but, as it seemed, ineffectively.

i had little enough opportunity to survey my surroundings; yet even in those brief, breathless moments i saw enough of the place wherein we stood to make me doubt the evidence of my senses! outside, i knew, lay a dingy wharf, amid a maze of mean streets; here was an opulently furnished apartment with a strong oriental note in the decorations!

snatching an electric torch from his pocket, harley leaped through a doorway draped with rich persian tapestry, and i came close on his heels. outside was darkness. a strong draught met us; and, passing along a carpeted corridor, we never halted until we came to a room filled with the weirdest odds and ends, apparently collected from every quarter of the globe.

crack!

a bullet flattened itself on the wall behind us!

“good job he can't shoot straight!” rapped harley.

the ray of the torch suddenly picked out the head and shoulders of a man who was descending through a trap in the floor! ere we had time to shoot he was gone! i saw his brown fingers relax their hold—and a bundle which he had evidently hoped to take with him was left lying upon the floor.

together we ran to the trap and looked down.

slowly moving tidal water flowed darkly beneath us! for twenty breathless seconds we watched—but nothing showed upon the surface.

“i hope his swimming is no better than his shooting,” i said.

“it can avail him little,” replied harley grimly; “a river-police boat is waiting for anyone who tries to escape from that side of the house. we are by no means alone in this affair, knox. but, firstly, what have we here!” he took up the bundle which the fugitive had deserted. “something incriminating when ali of cairo dared not stay to face it out! he would never have deserted this place in the ordinary way. that fellow who was such a bad shot was left behind, when the news of our approach reached here, to make a desperate attempt to remove some piece of evidence! i'll swear to it. but we were too soon for him!”

all the time he was busily removing the pieces of sacking and scraps of oriental stuff with which the bundle was fastened; and finally he drew out a dress-suit, together with the linen, collar, shoes, and underwear—a complete outfit, in fact—and on top of the whole was a soft gray felt hat!

eagerly harley searched the garments for some name of a maker by which their owner might be identified. presently, inside the lining of the breast pocket, where such a mark is usually found, he discovered the label of a well-known west end firm.

“the police can confirm it, knox!” he said, looking up, his face slightly flushed with triumph; “but i, personally, have no doubt!”

“you may have no doubt, harley,” i retorted, “but i am full of doubt! what is the significance of this discovery to which you seem to attach so much importance?”

“at the moment,” replied my friend, “never mind; i still have hopes—although they have grown somewhat slender—of making a much more important discovery.”

“why not permit the police to aid in the search?”

“the police are more useful in their present occupation,” he replied. “we are dealing with the most cunning knave produced by east or west, and i don't mean to let him slip through my fingers if he is in this house! nevertheless, knox, i am submitting you to rather an appalling risk, i know; for our man is desperate, and if he is still in the place will prove as dangerous as a cornered rat.”

“but the man who dropped through the trap?”

“the man who dropped through the trap,” said harley, “was not ali of cairo—and it is ali of cairo for whom i am looking!”

“the hunchback we saw to-night?”

harley nodded, and having listened intently for a few moments, proceeded again to search the singular apartments of the abode. in each was evidence of oriental occupancy; indeed, some of the rooms possessed a sort of arabian nights atmosphere. but no living creature was to be seen or heard anywhere. it was while the two of us, having examined every inch of wall, i should think, in the building, were standing staring rather blankly at each other in the room with the lighted lantern, that i saw harley's expression change.

“why,” he muttered, “is this one room illuminated—and all the others in darkness?”

even then the significance of this circumstance was not apparent to me. but harley stared critically at an electric switch which was placed on the immediate right of the door and then up at the silk-shaded lantern which lighted the room. crossing, he raised and lowered the switch rapidly, but the lamp continued to burn uninterruptedly!

“ah!” he said—“a good trick!”

grasping the wooden block to which the switch was attached, he turned it bodily—and i saw that it was a masked knob; for in the next moment he had pulled open the narrow section of wall—which proved to be nothing less than a cunningly fitted door!

a small, dimly lighted apartment was revealed, the oriental note still predominant in its appointments, which, however, were few, and which i scarcely paused to note. for lying upon a mattress in this place was a pretty, fair-haired girl!

she lay on her side, having one white arm thrown out and resting limply on the floor, and she seemed to be in a semi-conscious condition, for although her fine eyes were widely opened, they had a glassy, witless look, and she was evidently unaware of our presence.

“look at her pupils,” rapped harley. “they have drugged her with bhang! poor, pretty fool!”

“good god!” i cried. “who is this, harley?”

“molly clayton!” he answered. “thank heaven we have saved one victim from ali of cairo.”