With the main stream of history, to which we have before referred, we have no concern in this book. He who would embark thereon must sail a powerful vessel which must carry many guns. Also for the conduct of this vessel many qualities are necessary: a commanding intellect, acute perceptions, indefatigable industry, complete leisure, are among those things necessary to the pilot. These must be supplemented by a genius for research, a knowledge of ancient and modern languages, and an unerring faculty for separating the few precious grains of wheat from those mountains of chaff which he will have to sift with the utmost care. There are, however, subsidiary rivulets which feed the onward flow of events, and of such is the story of the Sea-wolves of the Mediterranean. On these the adventurous mariner can sail his little cockboat, discreetly retiring before he becomes involved and engulfed in the main stream. That he cannot altogether avoid it is shown by the fact that the men who are here chronicled took part in events of first-class importance in the age in which they lived. Kheyr-ed-Din Barbarossa fought the battle of Prevesa against his lifelong antagonist, Andrea Doria. Dragut was killed at the siege of Malta, at the moment almost of the fall of the castle of St. Elmo; had he lived it is more than probable that Jean Parisot de la Valette and his heroic garrison would have been defeated instead of being victorious. Ali Basha was the one Moslem commander who increased his reputation at the battle of Lepanto, because, as was usual in all maritime conflicts of the time, the corsairs, who had the habit of the sea, were more than a match for soldiers embarked to fight on an unfamiliar element. We shall speak, later on, of the autocratic rule of these leaders who possessed so absolute a domination over the men by whom they were followed. The fact of this absolute supremacy on the part of the chiefs is very curious, as theoretically in the confederacy of the Sea-wolves all were equal; we are, in fact, confronted with pure democracy, where every man was at liberty to do what seemed best in his own eyes. He was a free agent, none coercing him or desiring him to place himself under discipline or command. This, be it observed, was the theory. As a matter of fact the corsairs, who were extraordinarily successful in their abominable trade, abode beneath an iron and rigid discipline. This was enforced by the lash, as we shall see later on when it is related how Kheyr-ed-Din Barbarossa flogged one Hassan, a captain who, he considered, had failed in his duty: or by the actual penalty of death, which Uruj Barbarossa inflicted on one who had dared to act independently of his authority.