But the iron screw-propellers had scarcely begun to move in the opposite direction, before the two crabs, each now lying at right angles with the length of the ship, but neither of them directly astern of her, made a dash with open nippers, and Crab J fastened upon one propeller, while Crab K laid hold of the other. There was a din and crash of breaking metal, two shocks which were felt throughout the vessel, and the shattered and crushed blades of the propellers of the great battleship were powerless to move her. The captain of the Adamant, pallid with fury, stood upon the poop. In a moment the crabs would be at his rudder! The great gun, double-shotted and ready to fire, was hanging from its boom over the stern. Crab K, whose roof had the additional protection of spring armour, now moved round so as to be directly astern of the Adamant. Before she could reach the rudder, her forward part came under the suspended cannon, and two massive steel shot were driven down upon her with a force sufficient to send them through masses of solid rock; but from the surface of elastic steel springs and air-buffers they bounced upward, one of them almost falling on the deck of the Adamant. The gunners of this piece had been well trained. In a moment the boom was swung around, the cannon reloaded, and when Crab K fixed her nippers on the rudder of the Adamant, two more shot came down upon her. As in the first instance she dipped and rolled, but the ribs of her uninjured armour had scarcely sprung back into their places, before her nippers turned, and the rudder of the Adamant was broken in two, and the upper portion dragged from its fastenings then a quick backward jerk snapped its chains, and it was dropped into the sea. A signal was now sent from Crab J to Repeller No. 7, to the effect that the Adamant had been rendered incapable of steaming or sailing, and that she lay subject to order. Subject to order or not, the Adamant did not lie passive. Every gun on board which could be sufficiently depressed, was made ready to fire upon the crabs should they attempt to get away. Four large boats, furnished with machine guns, grapnels, and with various appliances which might be brought into use on a steel-plated roof, were lowered from their davits, and immediately began firing upon the exposed portions of the crabs. Their machine guns were loaded with small shells, and if these penetrated under the horizontal plates of a crab, and through the heavy glass which was supposed to be in these interstices, the crew of the submerged craft would be soon destroyed. The quick eye of the captain of the Adamant had observed through his glass, while the crabs were still at a considerable distance, their protruding air-pipes, and he had instructed the officers in charge of the boats to make an especial attack upon these. If the air-pipes of a crab could be rendered useless, the crew must inevitably be smothered.