Having gathered his band, procured provisions (chiefly by plundering), and built a fleet of boats, Morgan put his forces in motion. The first obstacle in his path was the Castle of Chagres, which guarded the mouth of the Chagres River, up which the buccaneers must pass to reach the city of Panama. To capture this fortress, Morgan sent his vice-admiral Bradley, with four hundred men. The Spaniards were evidently warned of their approach; for hardly had the first ship flying the piratical ensign appeared at the mouth of the river, when the royal standard of Spain was hoisted above the castle, and the dull report of a shotted gun told the pirates that there was a stubborn resistance in store for them. Landing some miles below the castle, and cutting their way with hatchet and sabre through the densely interwoven vegetation of a tropical jungle, the pirates at last reached a spot from which a clear view of the castle could be obtained. As they emerged from the forest to the open, the sight greatly disheartened them. They saw a powerful fort, with bastions, moat, drawbridge, and precipitous natural defences. Many of the pirates advised a retreat; but Bradley, dreading the anger of Morgan, ordered an assault. Time after time did the desperate buccaneers, with horrid yells, rush upon the fort, only to be beaten back by the well-directed volleys of the garrison. They charged up to the very walls, threw over fireballs, and hacked the timbers with axes, but to no avail. From behind their impregnable ramparts, the Spaniards fired murderous volleys, crying out.-- "Come on, you English devils, you heretics, the enemies of God and of the king! Let your comrades who are behind come also. We will serve them as we have served you. You shall not get to Panama this time." As night fell, the pirates withdrew into the thickets to escape the fire of their enemies, and to discuss their discomfiture. As one group of buccaneers lay in the jungle, a chance arrow, shot by an Indian in the fort, struck one of them in the arm. Springing to his feet with a cry of rage and pain, the wounded man cried out as he tore the arrow from the bleeding wound,-- "Look here, my comrades. I will make this accursed arrow the means of the destruction of all the Spaniards."