After taking on board a load of combustibles, the _Intrepid_ sailed from Syracuse for Tripoli upon the 3rd of February, 1804. The ketch itself had a varied history, for she was originally a French gun vessel, which had been captured by the English in Egypt and presented to Tripoli, and which finally was seized by Decatur while running for Constantinople with a present of female slaves for the Grand Vez[=i]r. The brig _Siren_, Lieutenant Charles Stewart, commanding, convoyed the expedition, and had orders to cover the retreat, and if feasible to assist the attack with its boats. In affairs of this kind personal comfort is always the least consideration, but had not the weather been pleasant, the hardships endured might seriously have affected the success of the enterprise. The five commissioned officers were crowded in the small cabin; the midshipmen and pilot on one side, and the seamen upon the other, were stowed like herrings upon "a platform laid across water-casks, whose surface they completely covered when they slept, and at so small a distance below the spar deck that their heads would reach it when seated." To these inconveniences were added the want of any room for exercise on deck, the attacks of innumerable vermin which their predecessors, the slaves, had left behind them, and (as the salted meat put on board had spoiled) the lack of anything but biscuits to eat and water to drink.
After a voyage of six days the town was sighted, but strong winds had rendered the entrances dangerous, and the heavy gale which came with night drove the Americans so far to the eastward before it abated that they found themselves fairly embayed in the Gulf of Sidra. On the afternoon of the 16th Tripoli was once more made out; and as the wind was light, the weather pleasant, and the sea smooth, Decatur determined to attack that night. By arrangement the _Siren_ kept almost out of sight during the day, and her appearance was so changed as to lull all suspicion of her true character. The lightness of the wind allowed the ketch to maintain the appearance of an anxious desire to reach the harbour before night, without bringing her too near to require any other change than the use of drags (in this case buckets towed astern) which could not be seen from the city. The crew was kept below, excepting six or eight persons at a time, so that inquiry might not be awakened by unusual numbers; and such men remained on deck as were dressed like Maltese. When the _Philadelphia_ was sighted, no doubt was left of the hazardous nature of the attack, for she lay a mile within the entrance, riding to the wind and abreast of the town. Her foremast, which was cut away while on the reef, had not yet been replaced, her main and mizzen masts were housed, and her lower yards were on the gunwales. The lower standing rigging, however, was set up, and her battery was loaded and shotted. She lay within short range of the guns on the castle, on the mole-head, and in the New Fort; and close aboard rode three Tripolitan cruisers and twenty gun-boats and galleys. To meet and overcome this force Decatur had a few small guns and seventy men, but these were hearts of oak, tried in many a desperate undertaking, and burning now to redeem their country's honour.