Sir Lucien spoke a few words rapidly in Chinese.  Sin Sin Wa performed his curious oriental shrug, and taking a fat leather wallet from his hip-pocket, counted out the sum of eighty-five pounds upon the counter.

“You catchee eighty-five,” he murmured.  “Too muchee price.”

The man grabbed the money and pocketed it without a word of acknowledgment.  He turned and strode along the room, his heavy, iron-clamped boots ringing on the paved floor.

“Fetch a grim, Sin Sin,” he cried.  “I’ll never get out if I don’t jump to it.”

Sin Sin Wa took the lantern from the counter and followed.  Opening a door at the further end of the place, he set the lantern at the head of three descending wooden steps discovered.  With the opening of the door the sound of lapping water had grown perceptibly louder.  George clattered down the steps, which led to a second but much stouter door.  Sin Sin Wa followed, nearly closing the first door, so that only a faint streak of light crept down to them.

The second door was opened, and the clangor of the Surrey shore suddenly proclaimed itself.  Cold, damp air touched them, and the faint light of the lantern above cast their shadows over unctuous gliding water, which lapped the step upon which they stood.  Slimy shapes uprose dim and ghostly from its darkly moving surface.

A boat was swinging from a ring beside the door, and into it George tumbled.  He unhitched the lashings, and strongly thrust the boat out upon the water.  Coming to the first of the dim shapes, he grasped it and thereby propelled the skiff to another beyond.  These indistinct shapes were the piles supporting the structure of a wharf.

“Good night, guv’nor!” he cried hoarsely

“So-long,” muttered Sin Sin Wa.

He waited until the boat was swallowed in the deeper shadows, then reclosed the water-gate and ascended to the room where Sir Lucien awaited.  Such was the receiving office of Sin Sin Wa.  While the wharf remained untenanted it was not likely to be discovered by the authorities, for even at low tide the river-door was invisible from passing craft.  Prospective lessees who had taken the trouble to inquire about the rental had learned that it was so high as to be prohibitive.

Sin Sin Wa paid fair prices and paid cash.  This was no more than a commercial necessity.  For those who have opium, cocaine, veronal, or heroin to sell can always find a ready market in London and elsewhere.  But one sufficiently curious and clever enough to have solved the riddle of the vacant wharf would have discovered that the mysterious owner who showed himself so loath to accept reasonable offers for the property could well afford to be thus independent.  Those who control “the traffic” control El Dorado—­a city of gold which, unlike the fabled Manoa, actually exists and yields its riches to the unscrupulous adventurer.

Smiling his mirthless, eternal smile, Sin Sin Wa placed the newly purchased stock upon a shelf immediately behind Sam Tuk; and Sam Tuk exhibited the first evidence of animation which had escaped him throughout the progress of the “deal.”  He slowly nodded his hairless head.