All but silently we were feeling our way through the mist.  Astern died the clangor of dock and wharf into a remote discord.  Ahead hung the foggy curtain veiling the traffic of the great waterway; but through it broke the calling of sirens, the tinkling of bells.

The gentle movement of the screw ceased altogether. 
The launch lay heaving slightly upon the swells.

A distant throbbing grew louder—­and something advanced upon
us through the haze.

A bell rang and muffled by the fog a voice proclaimed itself—­ a voice which I knew.  I felt Weymouth writhing impotently beside me; heard him mumbling incoherently; and I knew that he, too, had recognized the voice.

It was that of Inspector Ryman of the river police and their launch was within biscuit-throw of that upon which we lay!

“’Hoy!  ’Hoy!”

I trembled.  A feverish excitement claimed me.  They were hailing us.  We carried no lights; but now—­and ignoring the pain which shot from my spine to my skull I craned my neck to the left—­the port light of the police launch glowed angrily through the mist.

I was unable to utter any save mumbling sounds, and my companions were equally helpless.  It was a desperate position.  Had the police seen us or had they hailed at random?  The light drew nearer.

“Launch, ’hoy!”

They had seen us!  Fu-Manchu’s guttural voice spoke shortly—­ and our screw began to revolve again; we leaped ahead into the bank of darkness.  Faint grew the light of the police launch—­and was gone.  But I heard Ryman’s voice shouting.

“Full speed!” came faintly through the darkness.  “Port!  Port!”

Then the murk closed down, and with our friends far astern of us we were racing deeper into the fog banks—­speeding seaward; though of this I was unable to judge at the time.

On we raced, and on, sweeping over growing swells.  Once, a black, towering shape dropped down upon us.  Far above, lights blazed, bells rang, vague cries pierced the fog.  The launch pitched and rolled perilously, but weathered the wash of the liner which so nearly had concluded this episode.  It was such a journey as I had taken once before, early in our pursuit of the genius of the Yellow Peril; but this was infinitely more terrible; for now we were utterly in Fu-Manchu’s power.

A voice mumbled in my ear.  I turned my bound-up face; and Inspector Weymouth raised his hands in the dimness and partly slipped the bandage from his mouth.

“I’ve been working at the cords since we left those filthy cellars,” he whispered.  “My wrists are all cut, but when I’ve got out a knife and freed my ankles—­”

Smith had kicked him with his bound feet.  The detective slipped the bandage back to position and placed his hands behind him again.  Dr. Fu-Manchu, wearing a heavy overcoat but no hat, came aft.  He was dragging Karamaneh by the wrists.  He seated himself on the cushions near to us, pulling the girl down beside him.  Now, I could see her face—­and the expression in her beautiful eyes made me writhe.