18. This valley in ancient days formed the kingdom of Assyria, as the valley of the Nile formed that of Egypt. In the work now before us, we have nothing to do with its people, who were to the Jews merely a hostile power of captivity, inexorable as the clay of their walls, or the stones of their statues; and, after the birth of Christ, the marshy valley is no more than a field of battle between West and East. Beyond the great river,--Persia, India, and China, form the southern 'Oriens.' Persia is properly to be conceived as reaching from the Persian Gulf to the mountain chains which flank and feed the Indus; and is the true vital power of the East in the days of Marathon: but it has no influence on Christian history except through Arabia; while, of the northern Asiatic tribes, Mede, Bactrian, Parthian, and Scythian, changing into Turk and Tartar, we need take no heed until they invade us in our own historic territory. 19. Using therefore the terms 'Gothic' and 'Classic' for broad distinction of the northern and central zones of this our own territory, we may conveniently also use the word 'Arab'[27] for the whole southern zone. The influence of Egypt vanishes soon after the fourth century, while that of Arabia, powerful from the beginning, rises in the sixth into an empire whose end we have not seen. And you may most rightly conceive the religious principle which is the base of that empire, by remembering, that while the Jews forfeited their prophetic power by taking up the profession of usury over the whole earth, the Arabs returned to the simplicity of prophecy in its beginning by the well of Hagar, and are not opponents to Christianity; but only to the faults or follies of Christians. They keep still their faith in the one God who spoke to Abraham their father; and are His children in that simplicity, far more truly than the nominal Christians who lived, and live, only to dispute in vociferous council, or in frantic schism, the relations of the Father, the Son, and the Holy Ghost. [Footnote 27: Gibbon's fifty-sixth chapter begins with a sentence which may be taken as the epitome of the entire history we have to investigate: "The three great nations of the world, the Greeks, the Saracens, and the Franks, encountered each other on the theatre of Italy." I use the more general word, Goths, instead of Franks; and the more accurate word, Arab, for Saracen; but otherwise, the reader will observe that the division is the same as mine. Gibbon does not recognize the Roman people as a nation--but only the Roman power as an empire.]