The most formidable objects of defence were the two torpedo-tubes, which were removed from the ship and placed in position on shore four hundred yards below the chain boom. To enable the torpedoes to be fired, light piers were thrown out from the banks into twelve feet of water, the structure being hidden by boughs of trees and clumps of reeds. On the high ground at the back of the torpedo station searchlights were mounted. These were not to be used as a precautionary measure, but only to be switched on when an attack was visibly imminent. Von Riesser's principal aim was to remain hidden. If his retreat were discovered then he would put up a fight, and failing to win would surrender with a good conscience. Long before the three days had elapsed Denbigh had quite recovered from the effects of his prolonged immersion. He had, with the rest of the captured British officers, little opportunity of finding out the actual steps that were being taken for defence. They knew that work was in progress, but during the removal of the torpedo-tubes and guns they had been sent below. One discovery Denbigh made, and that was through overhearing a chance conversation between two German petty officers. It also accounted for the seemingly purposeless reluctance to confine the prisoners in the hold instead of attempting to chloroform them in their cabin. The _Pelikan_ was double-skinned, but the space between the double bottoms was far greater than is usual in marine construction. It had practically two hulls, one within the other, and in the intervening space were stowed quantities of warlike stores. When the _Pelikan_ had been boarded by a British patrol officer the deception escaped detection. Apparently the _Zwaan_ was a harmless Dutch liner. The sub-lieutenant who acted as boarding-officer was not sufficiently versed in the ways of the wily Teuton. An examination of the hold revealed nothing suspicious, and the vessel was accordingly released. Unfortunately for the Germans their plans had gone awry, for on grounding on the outer bar the ship had strained several of her plates, with the result that the space between the inner and the outer skin was flooded. Not only were the stores spoilt, but, in order to lighten her draught in addition to compensating for lost buoyancy, cargo more than equivalent to that flooded had to be jettisoned. Having landed the quick-firers and torpedo-tubes, the crew of the _Pelikan_ proceeded to increase the disguise of the ship. She was now a regular floating palm forest. So thick was the foliage brought on board and secured to the masts and upper works that sun-awnings were unnecessary. Even an observer in a seaplane, unless he were prepared for such a disguise, would fail to distinguish the raider in her garb of verdure. "How do you feel for another jaunt ashore?" asked Denbigh.