The basis of family prosperity is found in those qualities of a vigorous stock which insure success in war and the accumulation of wealth. To have many sons is, therefore, an ideal and to have them leagued together in the interest of family strength is in some degree a necessity. The simple government required is exercised by the patriarch of the family. Such a strong, growing family will be joined by other families in self-defence and will rapidly develop into a strong tribe if no untoward accident befalls it. These different families are only theoretically of one blood, though by marriage the original differences may be minimized. They are known by some common tribal name and brand their camels with a common tribal mark, or “wasm.” Their greatest need, practically their religion, is the existence for which they strive. A kind of morale ensues which is the tribal convention. According to it the women have their work, often very hard, the men their duties of brotherhood, raid and revenge. Even the children have their sphere into which they fit according to sex and into which the stranger may not come at all except by the fiction of relationship. It will be readily seen that, in a land of wastes where groups only can exist and no mere individual, to be excluded by the judgment of the tribe from its membership would mean death. Such outlawing is the ultimate treatment of the serious offender. Patriotism is that higher form of self-interest which makes an Arab the devotee of his tribe’s welfare. The successes, failures, quarrels and fate of the tribe are his own. The results of the raid, whether gain or loss, are shared. The shaykh of the tribe is its leading man, not a legislator. He exerts authority by personal influence and moral suasion and cannot constrain otherwise, in theory at least, any member of his tribe. The preëminence is likely to remain in his family if it continues noble and well-to-do, a useful object of pride to the tribe. If a higher organization of the tribal life should follow upon extension of power, the leading man may become a prince or emir or even a conqueror and ruler, as on several occasions in history. The passions of the Arab are intense. His hungry life for so large a part of the year, his picturesque imagination, and simple demands join with a chivalry born of the tribal manners to make him cultivate at once ideals of generosity and vengeful hate. To be a noble host of the wayfarer and the implacable foe of the one who has harmed him are equally demanded by his code. ‛Abd al-Malik the son of ‛Abd ar-Rahim, a poet of the Sons of Dayyan, sang: