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....