As soon as the repeller had been sighted from the Adamant, a strict lookout had been kept for the approach of crabs; and when the small exposed portions of the backs of two of these were perceived glistening in the sunlight, the speed of the great ship slackened. The ability of the Syndicate's submerged vessels to move suddenly and quickly in any direction had been clearly demonstrated, and although a great ironclad with a ram could run down and sink a crab without feeling the concussion, it was known that it would be perfectly easy for the smaller craft to keep out of the way of its bulky antagonist. Therefore the Adamant did not try to ram the crabs, nor to get away from them. Her commander intended, if possible, to run down one or both of them; but he did not propose to do this in the usual way.

As the crabs approached, the stern-jacket of the Adamant was let down, and the engines were slowed. This stern-jacket, when protecting the rudder and propellers, looked very much like the cowcatcher of a locomotive, and was capable of being put to a somewhat similar use. It was the intention of the captain of the Adamant, should the crabs attempt to attach themselves to his stern, to suddenly put on all steam, reverse his engines, and back upon them, the stern-jacket answering as a ram.

The commander of the Adamant had no doubt that in this way he could run into a crab, roll it over in the water, and when it was lying bottom upward, like a floating cask, he could move his ship to a distance, and make a target of it. So desirous was this brave and somewhat facetious captain to try his new plan upon a crab, that he forebore to fire upon the two vessels of that class which were approaching him. Some of his guns were so mounted that their muzzles could be greatly depressed, and aimed at an object in the water not far from the ship. But these were not discharged, and, indeed, the crabs, which were new ones of unusual swiftness, were alongside the Adamant in an incredibly short time, and out of the range of these guns.

Crab J was on the starboard side of the Adamant, Crab K was on the port side, and, simultaneously, the two laid hold of her. But they were not directly astern of the great vessel. Each had its nippers fastened to one side of the stern-jacket, near the hinge-like bolts which held it to the vessel, and on which it was raised and lowered.

In a moment the Adamant began to steam backward; but the only effect of this motion, which soon became rapid, was to swing the crabs around against her sides, and carry them with her. As the vessels were thus moving the great pincers of the crabs were twisted with tremendous force, the stern-jacket on one side was broken from its bolt, and on the other the bolt itself was drawn out of the side of the vessel. The nippers then opened, and the stern-jacket fell from their grasp into the sea, snapping in its fall the chain by which it had been raised and lowered.

This disaster occurred so quickly that few persons on board the Adamant knew what had happened. But the captain, who had seen everything, gave instant orders to go ahead at full speed. The first thing to be done was to get at a distance from those crabs, keep well away from them, and pound them to pieces with his heavy guns.

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.