Poland blinked his small eyes, cleared his throat, and looked down at the floor uneasily.  Then: 

“Who’s Cohen?” he grunted.

“You mean, who was Cohen?” cried Kerry.

The shot went home.  The man clenched his fists and looked about the room from face to face.

“You don’t tell me------” he began huskily.

“I’ve told you,” said Kerry.  “He’s on the slab.  Spit out the truth; it’ll be good for your health.”

The man hesitated, then looked up, his eyes half closed and a cunning expression upon his face.

“Make out your own case,” he said.  “You’ve got nothing against me.”

Kerry snapped his teeth together viciously.

“I’ve told you what happened to your pal,” he warned.  “If you’re a wise man you’ll come in on our side, before the same thing happens to you.”

“I don’t know what you’re talking about,” growled Poland.

Kerry nodded to the constable at the doorway.

“Take him back,” he ordered.

Jim Poland being returned to his cell, Kerry, as the door closed behind the prisoner and his guard, stared across at Durham where he stood beside the table.

“An old hand,” he said.  “But there’s another way.”  He glanced at the officer in charge.  “Hold him till the morning.  He’ll prove useful.”

From his waistcoat pocket he took out a slip of chewing gum, unwrapped it, and placed the mint-flavoured wafer between his large white teeth.  He bit upon it savagely, settled his hat upon his head, and, turning, walked toward the door.  In the doorway he paused.

“Come with me, Durham,” he said.  “I am leaving the conduct of the case entirely in your hands from now onward.”

Detective Durham looked surprised and not a little anxious.

“I am doing so for two reasons,” continued the Chief Inspector.  “These two reasons I shall now explain.”

III

THE SECRET TREASURE-HOUSE

Unlike its sister colony in New York, there are no show places in Limehouse.  The visitor sees nothing but mean streets and dark doorways.  The superficial inquirer comes away convinced that the romance of the Asiatic district has no existence outside the imaginations of writers of fiction.  Yet here lies a secret quarter, as secret and as strange, in its smaller way, as its parent in China which is called the Purple Forbidden City.

On a morning when mist lay over the Thames reaches, softening the harshness of the dock buildings and lending an air of mystery to the vessels stealing out upon the tide, a man walked briskly along Limehouse Causeway, looking about him inquiringly, as one unfamiliar with the neighbourhood.  Presently he seemed to recognize a turning to the right, and he pursued this for a time, now walking more slowly.

A European woman, holding a half-caste baby in her arms, stood in an open doorway, watching him uninterestedly.  Otherwise, except for one neatly dressed young Chinaman, who passed him about halfway along the street, there was nothing which could have told the visitor that he had crossed the borderline dividing West from East and was now in an Oriental town.