“Thank the guid God I see ye alive, Dan,” said Mary Kerry.  
Having her husband's dressing-gown over her night attire, and her usually neat hair in great disorder, she stood just within the doorway of the little dining-room at Spenser Road, her face haggard and the fey light in her eyes. Kerry, seated in the armchair dressed as he had come in from the street, a parody of his neat self with mud on his shoes and streaks of green slime on his overall, raised his face from his hands and stared at her wearily.
 
“I awakened wi' a cry at some hour afore the dawn,” she whispered stretching out her hands and looking like a wild-eyed prophetess of old. “My hairt beat sair fast and then grew caud. I droppit on my knees and prayed as I ha' ne'er prayed afore. Dan, Dan, I thought ye were gene from me.”
 
“I nearly was,” said Kerry, a faint spark of his old truculency lighting up the weary eyes. “The man from Whitehall only missed me by a miracle.”
 
“'Twas the miracle o' prayer, Dan,” declared his wife in a low, awe-stricken voice. “For as I prayed, a great comfort came to me an' a great peace. The second sight was wi' me, Dan, and I saw, no' yersel'—whereby I seemed to ken that ye were safe—but a puir dying soul stretched on a bed o' sorrow. At the fuit o' the bed was standing a fearsome figure o' a man—yellow and wicked, wi' his hands tuckit in his sleeves. I thought 'twas a veesion that was opening up tee me and that a' was about to be made clear, when as though a curtain had been droppit before my een, it went awe' an' I kenned it nae more; but plain—plain, I heerd the howling o' a dog.”
 
Kerry started and clutched the arms of the chair.
 
“A dog!” he said. “A dog!”
 
“The howling o' a sma' dog,” declared his wife; “and I thought 'twas a portent, an' the great fear came o'er me again. But as I prayed 'twas unfolder to me that the portent was no' for yersel' but for her—the puir weak hairt ye ha' tee save.”
 
She ceased speaking and the strange fey light left her eyes. She dropped upon her knees beside Kerry, bending her head and throwing her arms about him. He glanced down at her tenderly and laid his hands upon her shoulders; but he was preoccupied, and the next moment, his jaws moving mechanically, he was staring straight before him.
 
“A dog,” he muttered, “a dog!”
 
Mary Kerry did not move; until, a light of understanding coming into Kerry's fierce eyes, he slowly raised her and stood upright himself.
 
“I have it!” he said. “Mary, the case is won! Twenty men have spent the night and early morning beating the river bank so that the very rats have been driven from their holes. Twenty men have failed where a dog would have succeeded. Mary, I must be off.”
 
“Ye're no goin' out again, Dan. Ye're weary tee death.”
 
“I must, my dear, and it's you who send me.”
 
“But, Dan, where are ye goin'?”
 
Kerry grabbed his hat and cane from the sideboard upon which they lay, and:
 
“I'm going for the dog!” he rapped.
 
Weary as he was and travel-stained, for once neglectful of that neatness upon which he prided himself, he set out, hope reborn in his heart. His assertion that the very rats had been driven from their holes was scarce an exaggeration. A search-party of twenty men, hastily mustered and conducted by Kerry and Seton Pasha, had explored every house, every shop, every wharf, and, as Kerry believed, every cellar adjoining the bank, between Limehouse Basin and the dock gates. Where access had been denied them or where no one had resided they had never hesitated to force an entrance. But no trace had they found of those whom they sought.
 
For the first time within Kerry's memory, or, indeed, within the memory of any member of the Criminal Investigation Department, Detective-Sergeant Coombes had ceased to smile when the appalling truth was revealed to him that Sin Sin Wa had vanished—that Sin Sin Wa had mysteriously joined that invisible company which included Kazmah, Mrs. Sin and Mrs. Monte Irvin. Not a word of reprimand did the Chief Inspector utter, but his eyes seemed to emit sparks. Hands plunged deeply in his pockets he had turned away, and not even Seton Pasha had dared to speak to him for fully five minutes.
 
Kerry began to regard the one-eyed Chinaman with a superstitious fear which he strove in vain to stifle. That any man could have succeeded in converting a chandu-khan such as that described by Mollie Gretna into a filthy deserted dwelling such as that visited by Kerry, within the space of some thirty-six hours, was well nigh incredible. But the Chief Inspector had deduced (correctly) that the exotic appointments depicted by Mollie were all of a detachable nature—merely masking the filthiness beneath; so that at the shortest notice the House of a Hundred Raptures could be dismantled. The communicating door was a larger proposition, but that it was one within the compass of Sin Sin Wa its effectual disappearance sufficiently demonstrated.
 
Doubtless (Kerry mused savagely) the appointments of the opium-house had been smuggled into that magically hidden cache which now concealed the conjurer Sin Sin Wa as well as the other members of the Kazmah company. How any man of flesh and blood could have escaped from a six-roomed house surrounded by detectives surpassed Kerry's powers of imagination. How any apartment large enough to contain a mouse, much less half a dozen human beings, could exist anywhere within the area covered by the search-party he failed to understand, nor was he prepared to admit it humanly possible.
 
Kerry chartered a taxicab by Brixton Town Hall and directed the man to drive to Prince's Gate. To the curious glances of certain of his neighbors who had never before seen the Chief Inspector otherwise than a model of cleanliness and spruceness he was indifferent. But the manner in which the taxi-driver looked him up and down penetrated through the veil of abstraction which hitherto had rendered Kerry impervious to all external impressions, and:
 
“Give me another look like that, my lad,” he snapped furiously, “and I'll bash your head through your blasted wind-screen.”
 
A ready retort trembled upon the cabman's tongue, but a glance into the savage blue eyes reduced him to fearful silence. Kerry entered the cab and banged the door; and the man drove off positively trembling with indignation.
 
Deep in reflection the Chief Inspector was driven westward through the early morning traffic. Fine rain was falling, and the streets presented that curiously drab appearance which only London streets can present in all its dreary perfection. Workers bound Cityward fought for places inside trams and buses. A hundred human comedies and tragedies were to be witnessed upon the highways; but to all of them Kerry was blind as he was deaf to the din of workaday Babylon. In spirit he was roaming the bank of old Father Thames where the river sweeps eastward below Limehouse Causeway—wonder-stricken before the magic of the one-eyed wizard who could at will efface himself as an artist rubs out a drawing, who could camouflage a drug warehouse so successfully that human skill, however closely addressed to the task, failed utterly to detect its whereabouts. Above the discord of the busy streets he heard again and again that cry in the night which had come from a hapless prisoner whom they were powerless to succor. He beat his cane upon the floor of the cab and swore savagely and loudly. The intimidated cabman, believing these demonstrations designed to urge him to a greater speed, performed feats of driving calculated to jeopardize his license. But still the savage passenger stamped and cursed, so that the cabby began to believe that a madman was seated behind him.
 
At the corner of............