The Lieutenant smiled gravely. Did the figure wonder why he wore a cutlass in peace time? Did he realise the warning it embodied—the message they conveyed night by night to the anchored ships? His thoughts took a more sombre turn. Would the night ever come—just such a night as this—and under the fog a Menace glide in among the blindfold Fleet? To the first hail of alarm answer with a lever released, a silvery shadow that left a trail of bubbles on the surface.... And then—the fog and silence riven to the dark vault of heaven. He raised his head. "All right, Coxswain, enough for to-night. Carry on back." Over went the helm: the boat swung round on a new course, heading whence she had come an hour before. Carry on back! It was so easy to say. His thoughts reverted to the grim picture his imagination had created. How would that shadowy Terror, her mission fulfilled, "carry on back"? Wheel wrenched over, funnels spouting flame, desperate men clinging to the rail as she reeled under the concussion, racing blindly through the outraged night for safety. Thus had a warring Nation written a lesson across the map of Manchuria for all the world to read—and, if they might, remember. Where did he come in, then—this figure leaning thoughtfully against the angle of the steamboat’s cabin? What was his mission, and that of the steamboat with its armed crew, night after night, in fog and by starlight, winter and summer...? A chord of memory vibrated faintly in his mind. There was a phrase that summed it up, learned long ago.... He was a cadet again on the seamanship-deck of the old _Britannia_, at instruction in a now obsolete method of sounding with the Deep-Sea Lead and Line. They were shown how, in order to obtain a sounding, a number of men were stationed along the ship’s side, each holding a coil of the long line. As the heavy lead sank and the line tautened from hand to hand, each man flung his coil overboard. As he did so he called to warn the next— "Watch there, watch!" The steamboat, slowed as she passed close under the stern of a battleship. The fog had lifted, and the Officer of the Middle Watch was leaning over the quarter-deck rail. The Lieutenant of the Night Guard raised his head, and in the gleam of the ship’s stern light the two officers recognised each other. They had been in the _Britannia_, together. The former laughed a greeting. "Go back to bed, you noisy blighter!" The cloaked figure in the boat chuckled. "That’s where I am going," he called back. *XVII.* *"FAREWELL AND ADIEU!"* The Junior Watch-keeper paused at the corner of the street and smote the pavement with the ferrule of his stick.