As the sea has furnished opportunities for so much good,—for manly exertion, knowledge of the world, and acquaintance with people outside of one’s own country, and for gaining wealth,—so it has given a chance for unscrupulous men to show the worst that is in them; and the guarding of shore towns and merchant vessels from piratical attacks has always been a part of the usefulness and duty of a nation’s naval force. As on land there are robbers and highwaymen, so on the ocean robber ships have often been lying in wait for vessels loaded with treasure, and have landed crews of marauders to make havoc with rich seaboard provinces. Such robbers on the high seas are termed pirates, and their crime was visited by the old laws with torturing punishments; yet they were never more daring than when the laws against them were severest. The word is Greek, and the first pirates who figure in history are those of the Greek and Byzantine islands and coasts—bloody ruffians who originated the amusing method of disposing of unransomed prisoners by making them “walk the plank,” as has been done within the present century. The intricate channels and hidden harbors of the Ægean Sea long remained a hiding-place of sea-robbers, and are still haunted by them, though every few years, from Cæsar’s time till now, the kings of the surrounding countries have sent expeditions to break them up. In the sixteenth century piracy in that region was especially prevalent. The crews then were chiefly Turkish, but the great leaders were two renegade Greeks, the brothers Aruck and Hayradin Barbarossa (“Redbeard”). [Illustration: WALKING THE PLANK.]