For this purpose, ten large ships, from 600 to 1400 tons burden, had been cut-down, and 200,000 cubic feet of timber worked in their construction. To protect them from bombs, and the men at the batteries from grape, or descending shot, a hanging roof was contrived; which was worked up and down by springs. The roof was composed of a strong rope-work netting, laid over with a thick covering of wet hides, while its sloping position was calculated to prevent shells from lodging, and to throw them off into the sea before they could burst. To render the fire of these batteries the more rapid, a kind of match had been contrived, so to be placed that all the guns in the battery could go off at the same instant. To defend them from red-hot shot, with which the fortress was supplied, the newest part of the plan was that by which water could be carried in every direction to neutralise its effect. In imitation of the circulation of the blood, a variety of pipes and canals perforated all the solid workmanship in such a manner that a continued succession of water could be conveyed to every part of the structure, a number of pumps being adapted to afford an unlimited supply. It was thus believed that these terrible machines, capable of inflicting destruction, would themselves be invulnerable. The largest carried 21 guns, and their complement of men was 36 for each gun in use, exclusive of officers and mariners for working the ships. General Elliot, undaunted by the preparations made by the enemy, determined to try what he and his brave garrison could do to counteract them. Accordingly, at seven o'clock in the morning of the 8th of September, he opened a tremendous fire on their works with red-hot shot, carcasses, and shells. At ten o'clock the Mahon battery, with the one adjoining it, were in flames. By five in the evening both were entirely consumed; a great part of the eastern parallel, and of the trenches and parapet for musketry, were likewise destroyed. A large battery near the bay was so much damaged by having repeatedly been set on fire, that the enemy were compelled to abandon it, while they lost an immense number of men in their endeavour to extinguish the flames. The next day the French and Spaniards opened a new battery of 64 heavy cannon, which, with the artillery from the lines and mortars, continued to play upon the garrison without intermission the whole day. At the same time, seven Spanish ships of the line and two French, with some frigates and small vessels, passing along the works discharged their broadsides, until they had passed Europa Point, and got into the Mediterranean. In the meantime, the English squadron being too small to compete with them, the seamen had been landed, under the command of Captain Roger Curtis, and had been placed in the batteries at Europa Point. Hence they had attacked the Spanish line-of-battle ships, and compelled them to haul off.