All three tugs were blowing off steam vigorously. The hiss of the escaping vapour had prevented the Huns from hearing the noisy British seaplane's approach, and now at an altitude of five thousand feet Barcroft had the huge target at his mercy. It was, however, necessary to descend considerably. There must be no risk of missing the slowly-moving battleship. Descending in short right-handed spirals the pilot brought his craft within five hundred feet of his enemy. A bugle-blast, followed by the appearance of swarms of sailors as they rushed to man the light quick-firers, announced that the impending danger had been sighted. At all events, it was not to be a one-sided engagement, for almost simultaneously two anti-aircraft guns, mounted on the battleship's for'ard turret, came into action. Both shells passed so close to the seaplane that the pilot distinctly felt the "windage" of the projectiles, The frail aircraft reeled in the blast of the displaced air, but fortunately the time-fuses of the shells were not set accurately. The missiles burst over eight hundred feet above their target. Deftly Kirkwood released a couple of bombs. Both found their objective, one striking the fo'c'sle between the steam capstan and the for'ard turret, the other slightly in the wake of the bridge and chart-house, completely wrecking both. In a few seconds the whole of the fore-part of the battleship was hidden by a dense cloud of smoke. "Not so dusty," thought Billy as he manoeuvred to enable the observer to drop another couple of "plums." As he did so a shell burst almost underneath the seaplane, ripping a dozen holes in the wings and severing a strut like a match-stick. Out of the enveloping mushroom-shaped cloud of white smoke the seaplane staggered. For the moment Billy fancied that she was out of control and on the point of making a fatal nose-spin. "Let's hope, then, that she'll drop fairly on top of that strafed hooker," was the thought that flashed across his mind. But no; grandly the gallant little seaplane recovered herself. A touch of the pilot's feet upon the rudder-bar showed that she was capable of being steered, while apparently the controls were still in order. Billy gave a quick glance over his shoulder. To his relief he found Kirkwood cool and imperturbable at his post, awaiting the opportune moment to release another pair of powerful bombs. One burst aft, utterly knocking out the crew of the anti-aircraft gun that had so nearly strafed their attackers; the other, missing the warship's deck, landed fairly and squarely upon the tug lashed to the starboard side. The little vessel, totally ripped up amidships, sank amid the roar of escaping steam, but still secured by fore and aft "springs"--wire hawsers stout enough to withstand the strain--she acted as a tremendous drag upon the huge bulk of the battleship.