This system of irrigation, it is true, was not carried to perfection until a late period in the history of the Assyrian empire; but it must, at the same time, be recollected, that as far back as the light of history penetrates, it is always civilised man that is discerned in the valley of the Euphrates. The vague whisperings of tradition, even, cannot speak of a time when savage tribes wandered over its plains. If we investigate who were the settled inhabitants of the land when first the light of history breaks upon it—the people among whom the old Assyrian empire arose—we will come to the conclusion that the great mass of the population belonged to that purely Syrian race whose settlements have in all ages extended from the banks of the Euphrates to the shores of the Levant. But mixed with this race, very much in the neighbourhood of Babylon, and more faintly as we proceed northwards, were offshoots of the Cushite race,—a people having its principal seats in southern Arabia, along the coasts of the Indian and Red Seas, imperfectly represented by the Himyarite Arabs of the present day, and forming a connecting link between the old races of Syria and Egypt. Into the population thus constituted descended the Chaldeans,—a tribe from the highlands which border the Mesopotamian valley on the north-east, and who, though Syrians in the main, probably approximated somewhat in character to the Persian race. This tribe obtained the ascendant among the population at Nineveh and in the upper portion of the Mesopotamian valley,—imparting to that population, apparently, a sterner character than prevailed in the lower part of the valley and around Babylon. Frequent wars occurred between these half-rival half-sister cities; the general result of which was, that the people of Nineveh held the Babylonians in a more or less perfect state of dependence. In the course of time, too, the Cushite element in the Babylonian population (and which probably gave to it its turn for commerce and maritime enterprise) became extinct; while the Chaldean element, which differed but little from the general mass of the population, seems to have greatly increased. It was from Ur of the Chaldees, in the vicinity of Nineveh, that Abraham, in obedience to the Divine voice, went forth, journeying south-westwards, through the desert lying between the Euphrates and Syria, and, reaching Palestine, became the father of the Hebrew nation. From his loins also proceeded the Idumeans, who proved their superiority to the rest of the Arabian tribes by founding the kingdom of Edom, and excavating the wondrous rock-city of Petra.