In the story of the battles of Salamis and Actium we have seen what naval warfare was like in Greek and Roman times. It would be easy to add other examples, but they would be only repetitions of much the same story, for during the centuries of the Roman power there was no marked change in naval architecture or the tactics of warfare on the sea. We pass, then, over a thousand years to a record of naval war waged in the beginning of the Middle Ages by northern races--people who had, independently of Greek or Roman, evolved somewhat similar types of ships, but who were better sailors, though for all that they still used the ship not so much as an engine of war as the floating platform on which warriors might meet in hand-to-hand conflict. Norseman, Dane, and Swede were all of kindred blood. The land-locked Baltic, the deep fiords of the Scandinavian Peninsula, the straits and inlets of the archipelago that fringes its North Sea coast, were the waters on which they learned such skill in seamanship that they soon launched out upon the open sea, and made daring voyages, not only to the Orkneys and the Hebrides, and the Atlantic seaboard of Ireland, but the Faroes, and to still more distant Iceland and Greenland, and then southward to "Vineland," the mainland of America, long after rediscovered by the navigators of the fifteenth century. There is a considerable intermixture of Norse blood in the peoples of Great Britain and Ireland, and perhaps from this sea-loving race comes some of the spirit of adventure that has helped so much to build up our own naval power. When Nelson destroyed and captured the Danish fleet at Copenhagen, the Danes consoled themselves by saying that only a leader of their own blood could have conquered them, and that Nelson's name showed he came of the Viking line. A chronicler tells how Charlemagne in his old age once came to a village on the North Sea shore, and camped beside it. Looking to seaward he saw far out some long low ships, with gaily painted oars, dragon-shaped bows, and sails made of brightly coloured lengths of stuff sewn together and adorned with embroidery along the yard. Tears came to his eyes as he said: "These sea-dragons will tear asunder the empire I have made."