The surprise was perfect. The men on the frigate's deck ran to the starboard side as their assailants poured in on the larboard, and constant plunges into the water told that they were hastily leaping overboard in their fright. Hardly a blow had been struck. The deck was cleared in almost a minute after the order to board. The only struggle took place below, but this lasted little longer. In less than ten minutes from the time of boarding all resistance was at an end, and the craft was an undisputed prize to the Intrepid's crew. And now to learn the meaning of this midnight assault. The vessel which had been so skilfully captured was the frigate Philadelphia, of the American navy, which had fallen into the hands of the Tripolitans some time before. For years the Moorish powers of Africa had been preying upon the commerce of the Mediterranean, until the weaker nations of Europe were obliged to pay an annual tribute for the security of their commerce. The United States did the same for some time, but the thing grew so annoying that war was at length declared against Tripoli, the boldest of these piratical powers. In 1803 Commodore Preble was sent with a fleet to the Mediterranean. He forced Morocco to respect American commerce, and then proceeded to Tripoli, outside whose harbor his fleet congregated, with a view of blockading the port. On October 31 Captain Bainbridge of the Philadelphia, while cruising about, saw a vessel in shore and to windward, standing for Tripoli. Sail was made to cut her off. The chase continued for several hours, the lead being kept constantly going to avoid danger of shoals. When about a league distant from Tripoli it became evident that the fugitive craft could not be overtaken, and the frigate wore round to haul off into deeper waters. But, to the alarm of the officers, they found the water in their front rapidly shoaling, it having quickly decreased in depth from eight to six and a half fathoms. A hasty effort was now made to wear the ship, but it was too late; the next instant she struck on a reef, with such force that she was lifted on it between five and six feet. This was an appalling accident. No other cruiser was near. The enemy was close at hand. Gunboats were visible near the town. The moment it was discovered that the frigate was in trouble these dogs of war would be out. Captain Bainbridge gave orders to lighten the ship with all speed. All but a few of her guns were thrown overboard. The anchors were cut from the bows. The water-casks in the hold were started, and the water pumped out. All heavy articles were thrown overboard, and finally the foremast was cut away. But all proved in vain. The ship still lay immovable on the rocks. The gunboats of the enemy now surrounded her, and were growing bolder every minute. There was nothing for it but surrender. Resistance could only end in the death of all on board.