Meanwhile the _Hammerer_ and her consorts had penetrated a considerable distance up the Dardanelles. Here they gave and received hard knocks, for the range averaged only two thousand yards. Several gaping holes appeared in the unarmoured portions of the _Hammerer's_ hull, her funnels were torn through and through, her after-bridge had been swept away, and almost every boat she carried was splintered. Yet her crew, well protected by the armoured barbettes and casemates, and the broad nine-inch belt extending two-thirds of her length, suffered little loss; and when at half-past two the _Vengeance_, _Irresistible_, _Albion_, _Swiftsure_, _Ocean_, and _Majestic_ steamed up to assist in the bombardment, the forts quickly ceased firing. During the lull in the firing Dick Crosthwaite had to go on deck to superintend the clearing away of some of the remains of the after-bridge, which interfered with the training of the starboard 6-inch gun. As he did so he saw the _Irresistible_ listing heavily. Whether mortally injured by gun-fire, torpedo, or mine, he knew not at the time, but it was certain that she was done for. An attempt was being made to take her in tow, but already the stanch old craft was heeling too much. Seeing the plight of the battleship, the Turks again opened fire, sending a hail of projectiles at the stricken ship. Her consorts attempted to intervene and screen her from the harassing storm of shell, for her devoted crew, working hard in a vain effort to check the inrush of water by means of collision mats, were fully exposed to the fire of the Turkish guns. Reluctantly the order was given to abandon ship, and in response to signals for assistance British destroyers dashed up, and, manoeuvring with the utmost skill and coolness under the galling fire, actually ran alongside the fast-sinking vessel. Most of the _Irresistible's_ crew succeeded in leaping upon the decks of the destroyers; a few had to take to the water, and were promptly hauled out by ready helpers. The rescuers were only just in time, for, amid a cloud of smoke and steam, the ship sank in deep water. The catastrophe was not the only one, for within a very few minutes after the sinking of the _Irresistible_, the _Ocean_, a slightly larger battleship, having struck a mine, sank, with very little loss of life. It was a black day for the Allies, for the French had not come off without serious losses. The _Bouvet_, fouling a mine, the detonation of which caused her principal magazine to explode, sank with appalling suddenness, taking with her practically the whole of the crew. The _Gaulois_, badly mauled by gun-fire, was obliged to haul out of line, and it was rumoured that she had to be beached on the island of Imbros. A new and hitherto unexpected danger had threatened the British and French battleships--a danger against which ordinary mine-sweeping was impracticable.