So ended the first Arab attack on Northern Africa. It had momentous consequences. Not only did it bind to Islam for twelve hundred years the provinces which for centuries before had been Christian and an appanage of Europe, but it paved the way for the Arab invasion of Spain. Abdulla’s raid was shortly followed by other military expeditions. Eighteen years later Sidi Okba, having established a permanent government, pursued his course through what is now Morocco to the Atlantic Ocean. In order to complete the downfall of Christianity, a special tax was imposed on Christians, a leaf out of the book of Constantine the Great, who, in order to ensure its spread through the Roman world, had ingeniously enacted that no pagan master should own a Christian slave. The tax had the effect desired, and the whole population embraced the faith and rule of Islam. Four hundred years later a great Arab immigration took place. The brigand tribes of Hillal and Soleim being driven from Arabia into Egypt, speedily found their way thence into Northern Africa, which they overran like a flight of locusts. From these nomad hordes are descended in the main the Arabs of to-day. If the true Arabs only represent a fraction of the total Mohammedan population, variously estimated at a third and a sixth, they have imposed on the remainder their language, their religion, their institutions, and their customs, with the result that in a sense all are Arabs, though not of race. The pure-bred Arab is of an aristocratic type—tall, thin, muscular, and of dignified carriage. His narrow and retreating forehead indicates no great brain power; this feature is sometimes so marked as to give an aspect of semi-idiocy. A rigorous childhood ensures the survival of the fittest; the Arab children are left to themselves, naked in heat and cold, in sun and rain and frost, and only the hardiest reach manhood. The result is seen in the finely tempered physique of the race, in the Arab’s extraordinary powers of endurance, and in his disregard of hardship and suffering. Whole tribes are infected with what are called the diseases of civilization; typhus and smallpox sometimes blaze like a flame among them; the Arab scorns precaution or cure, and lives or dies with indifference. As becomes his aristocratic traditions, he prefers war to peace, and plunder to work. His nomad life, which accords with these tastes, is probably an accident forced upon him by the climatic conditions of the country. His wealth depends on his flocks and herds, his very existence is tied to the necessity of finding pasture for them. New ground has ever to be sought, different altitudes being visited according to the season and the period of rainfall. For a people of filthy habits a nomad life has many advantages; the constant change of camping-ground counteracts in some degree the want of sanitary conditions. [Illustration: ALGIERS: MOORISH DOORWAY, RUE PORTE NEUVE]