From the main peak of the flag-ship Victory hung out Admiral Nelson's famous signal, "England expects every man to do his duty!" an inspiring appeal, which has been the motto of English warriors since that day. The fleet under the command of the great admiral was drawing slowly in upon the powerful naval array of France, which lay awaiting him off the rocky shore of Cape Trafalgar. It was the morning of October 21, 1805, the dawn of the greatest day in the naval history of Great Britain. Let us rapidly trace the events which led up to this scene,--the prologue to the drama about to be played. The year 1805 was one of threatening peril to England. Napoleon was then in the ambitious youth of his power, full of dreams of universal empire, his mind set on an invasion of the pestilent little island across the channel which should rival the "Invincible Armada" in power and far surpass it in performance. Gigantic had been his preparations. Holland and Belgium were his, their coast-line added to that of France. In a hundred harbors all was activity, munitions being collected, and flat-bottomed boats built, in readiness to carry an invading army to England's shores. The landing of William the Conqueror in 1066 was to be repeated in 1805. The land forces were encamped at Boulogne. Here the armament was to meet. Meanwhile, the allied fleets of France and Spain were to patrol the Channel, one part of them to keep Nelson at bay, the other part to escort the flotilla bearing the invading army. While Napoleon was thus busy, his enemies were not idle. The warships of England hovered near the French ports, watching all movements, doing what damage they could. Lord Nelson keenly observed the hostile fleet. To throw him off the track, two French naval squadrons set sail for the West Indies, as if to attack the British islands there. Nelson followed. Suddenly turning, the decoying squadron came back under a press of sail, joined the Spanish fleet, and sailed for England. Nelson had not returned, but a strong fleet remained, under Sir Robert Calder, which was handled in such fashion as to drive the hostile ships back to the harbor of Cadiz.