Lawless stopped and waited for the applause. "A very pretty conjuring trick," remarked Trent, as one humouring an amiable lunatic. "And what do you do now? Make it disappear up your sleeve or change it into a live rabbit?" "Oh, you blithering ass!" exclaimed the Lieutenant impatiently. "Can't you see? This is the means I've devised for revenging myself on that wretched skipper." "You're going to fill it with dynamite and explode it under his stern?" "No, my child, I'm not. Instead, I'm going to fix that line to the stanchions against his rudder-post so that the steamer will tow this barrel, which, being weighted, will be submerged and show only the pipe in a vertical position above the surface. Furthermore, the worthy Bates having fashioned the top thereof in the likeness of a periscope, the victim will think he's being chased by an enemy submarine and have divers fits and spasms in consequence. Do you grasp the idea _now_?" "It's pretty feeble, but I think I follow you," answered Trent. "Only you seem to have forgotten one thing, which is that as soon as the fog lifts and the skipper spots your barrel he'll pot it with his quick-firer. Then we shall read a hair-raising account of how the captain of the _Cotswold_ sank a _U_ boat which had been following her all night." "Not a bit of it, my son. They won't be able to hit that barrel in a month of Sundays, especially if we get a choppy sea by the morning." Trent shrugged his shoulders, but made no further comment. "And now," went on Lawless cheerfully, "it's time the plot thickened, so we'll proceed to drop the bean in the soup. Stand by the telegraph, for if we run our nose against the other fellow's counter the joke'll be on us." He leant over the bridge-rail and peered through the fog for the steamer, but, though he could hear the latter's engines, the vessel herself was invisible. The manoeuvre he proposed carrying out was, to put it mildly, risky, and no one but the feckless Lieutenant would have contemplated such a thing, much less have attempted to put it into execution. But no fear of possible consequences ruffled his serenity as, little by little, the _Knat_ cautiously overhauled the _Cotswold_, the noise of whose machinery completely drowned the hum of the destroyer's turbines. Some ten minutes elapsed, and then Lawless was able to make out the vessel's stern towering, dim and shadowy, above him. Then, taking the wheel from the hands of the quartermaster, he brought the _Knat's_ bows right under the steamer's counter. "Let her go," he said in a hoarse whisper.