Suddenly a black shape, distorted out of its proportion by the watery atmosphere, loomed up dead ahead. There was no attempt made by the vessel—for such it was—to give warning of her presence. She was simply forging ahead with bare steerage way.
Signalling to the rearmost tug to go full speed astern, the master of the leading tender promptly gave orders for the engines to be stopped. He dared not go astern, otherwise the momentum of the Impregnable would cause the giant vessel to overrun her diminutive escort. As it was the cruiser forged ahead till the tug was swept alongside.
Just then the mysterious vessel, that had made no attempt to get out of the way, went astern, and, describing a graceful curve, ran alongside the Impregnable. There was a rending of steel as the ex-cruiser's torpedonet-booms were shorn from their securing-lashings by the wall-sided vessel. The next instant fifty men poured upon the Impregnable's upper deck; hawsers were passed out and the two ships were soon locked in a close embrace.
Captain Stalkart, knowing that something was amiss, but ignorant of what had actually occurred, shouted through his megaphone for the other tug to come alongside. She promptly complied, making fast on the port side of the Impregnable, and slightly astern of the first tug.
Under the impression that a serious collision had occurred, and wishing to do his best to save the huge vessel he was towing, Stalkart gave orders for the powerful centrifugal pumps to be manned, and the suction-pipes to be led aboard the Impregnable; but ere the hoses could be coupled up a score of men armed with revolvers and automatic pistols lowered themselves over the cruiser's side, and on to the two tugs.
The phlegmatic Dutchmen, finding it useless to resist, promptly ran below, their retreat being hastened by a few pistol-shots fired over their heads. To do the crews of the tugs personal injury was evidently not the intention of the assailants.
As for Captain Stalkart, the minute he saw how things were turning out, he ran into the chart-room and seized a revolver. Fortunately for his own sake he did not attempt to fire, nor did the aggressors find him for some considerable time. During that interval he wrote a hurried message on one of the lifebuoys, and heaved it over the side.
Meanwhile, in addition to the work of pillaging both tugs of everything that might be of service, the modern buccaneers were busily engaged in transhipping stores, arms, and ammunition from the tramp to the Impregnable.
It was soon evident that they had laid their plans carefully beforehand, and that the capture of the Impregnable was not an act on the spur of the moment. From the hold of the steamer twenty-five seven-pounder quick-firers with their mountings were soon hauled up, and placed in position on the captured cruiser. Tons of oil were pumped into her double bottoms; water and provisions were stowed away in the usual tanks and store-rooms.
Down in the Impregnable's engine-room men—experienced mechanics—were overhauling the machinery. Only a few weeks before the cruiser had been in commission with a nucleus crew, and, as is usually the case, her engines had lacked proper attention, but in less than a couple of hours the filibusters had succeeded in firing the oil-fuel burners and raising steam.