I propose to tell in non-technical and popular language the story of some of the most remarkable episodes in the history of sea power. I shall begin with the first sea-fight of which we have a detailed history—the Battle of Salamis (B.C. 480), the victory by which Themistocles the Athenian proved the soundness of his maxim that "he who commands the sea commands all." I shall end with the last and greatest of naval engagements, the Battle of Tsu-shima, an event that reversed the long experience of victory won by West over East, which began with Salamis more than two thousand years ago. I shall have to tell of British triumphs on the sea from Sluys to Trafalgar; but I shall take instances from the history of other countries also, for it is well that we should remember that the skill, enterprise, and courage of admirals and seamen is no exclusive possession of our own people. I shall incidentally describe the gradual evolution of the warship from the wooden, oar-driven galleys that fought in the Straits of Salamis to the steel-built, steam-propelled giants that met in battle in the Straits of Tsu-shima. I shall have something to say of old seafaring ways, and much to tell of the brave deeds done by men of many nations. These true stories of the sea will, I trust, have not only the interest that belongs to all records of courage, danger, and adventure, but also some practical lessons of their own.