dad—in the ancient trackway of fertility. From this fertile base the Saracen power was carried into all the regions around in such manner as to make a bid for a truly World-Empire. North-eastward the Mohammedans ascended from Baghdad into Iran by the same passway which had guided the Parthians and Persians downward, and they spread even into Northern India. Southward they crossed from the Yemen headland of Arabia to the African coast south of the Sahara, and penetrated on their camels and horses through the whole breadth of the Sudan. Thus, like a vast eagle, their Empire of Land-power spread its wings from the Arabian Centreland, on the one hand over the Northern Heartland, far into the depths of Asia, and on the other hand over the Southern Heartland equally far into the depths of Africa.
But the Saracens were not content with a dominion based only on the means of mobility proper to their steppes and deserts; like their predecessors, the Phœnicians and Shebans, they took to the sea. Westward they travelled along the north coast of Africa, both on sea and land, until they came to two countries, Barbary and Spain, whose broad tablelands, neither utterly sterile like the Sahara, nor yet forested like most of the
