At last the slowly-moving convoy passed Yarmouth and sighted the Cork Lightship off the entrance to Harwich Harbour. Here the unwieldy tramps were practically immune from hostile action, for the air was stiff with aircraft and airships, while for miles round the sea was dotted with swiftly-moving destroyers, M.-L.'s, and submarine-chasers. It was no place for Fritz to show his nose, and to his discretion, if not to his credit, he left the approaches to Harwich severely alone. A wireless telegraphist, holding a folded slip of buff paper, ran up the bridge-ladder, and saluting Alec, who had just taken over as Officer of the Watch, handed him message. "Wireless just gone through, sir," he reported. "General signal to the convoy." Seton took the proffered signal-pad, read the message, and elevated his eyebrows. Long experience in naval matters had taught him never to show unwonted surprise at any order that might come through at any hour of the day or night. But this, on the face of it, seemed remarkable. Briefly, the convoy was to be split up, the major portion going into Harwich to await further orders. Four of the slowest tramps, escorted by the destroyers, _Bolero_ and _Triadur_, were to proceed to the Nord Hinder Lightship, there to stand by until instructions were sent to the destroyers by the S.N.O. "Wonder if the tramps are Q-boats after all," soliloquized Alec. "One doesn't know t'other from which in these jolly old times. . . . Chance of luring Fritz and seeing a bit of life, eh, what?" Five minutes later the convoy acted according to orders, the two destroyers and their sluggish charges shaping an easterly course through the mine-infested North Sea. CHAPTER IV Torpedoed "Port five--steady." "Port five it is, sir." Alec Seton, sheltering under the lee of the bridge dodger, raised his binoculars and peered steadfastly through the gloom. It was night. Patches of fog were ganging around with irritating persistency, as if bent on following and hampering the _Bolero's_ movements. There was just sufficient headwind to throw cascades of icy cold spray over the destroyer's flaring bows. The breeze whistled mournfully through the rigging, while aft a long trail of black smoke, beaten down by the heavy atmosphere, hung sullenly over the short, vicious seas. According to reckoning the Nord Hinder lay 5 miles east by north. It was not idle curiosity that had prompted Seton to order the course to be altered. Less than a mile away was something showing black and ill-defined even to the powerful night-glasses. It might be anything from a derelict tramp to an abandoned boat. It might be a German submarine or a sea-going torpedo-boat flying, or rather supposed to be flying, the craven Black Cross Ensign of Germany. Whatever it was, it was Seton's duty to investigate, taking proper precautions in the event of the object turning out to be a hostile warship.