15. Such is a broad and cursory outline of the theory according to which Cushite immigrations preceded the arrival of the Semites in the land of Shumir and Accad. Those who uphold it give several reasons for their opinion, such as that the Bible several times mentions a Cush located in the East and evidently different from the Cush which has been identified as Ethiopia; that, in Chap. X. of Genesis (8-12), Nimrod, the legendary hero, whose empire at first was in "the land of Shinar," and who is said to have "gone forth out of that land into Assyria," is called a son of Cush; that the most ancient Greek poets knew of "Ethiopians" in the far East as opposed to those of the South--and several more. Those scholars who oppose this theory dismiss it wholesale. They will not admit the existence of a Cushite element or migration in the East at all, and put down the expressions in the Bible as simple mistakes, either of the writers or copyists. According to them, there was only one immigration in the land of Shumir and Accad, that of the Semites, achieved through many ages and in numerous instalments. The language which superseded the ancient Shumiro-Accadian idiom is to them a Semitic one in the directest and most exclusive sense; the culture grafted on that of the earlier population is by them called purely "Semitic;" while their opponents frequently use the compound designation of "Cushito-Semitic," to indicate the two distinct elements of which, to them, it appears composed. It must be owned that the anti-Cushite opinion is gaining ground. Yet the Cushite theory cannot be considered as disposed of, only "not proven,"--or not sufficiently so, and therefore in abeyance and fallen into some disfavor. With this proviso we shall adopt the word "Semitic," as the simpler and more generally used. 16. It is only with the rise of Semitic culture in Southern Mesopotamia that we enter on a period which, however remote, misty, and full of blanks, may still be called, in a measure, "historical," because there is a certain number of facts, of which contemporary monuments give positive evidence. True, the connection between those facts is often not apparent; their causes and effects are frequently not to be made out save by more or less daring conjectures; still there are numerous landmarks of proven fact, and with these real history begins. No matter if broad gaps have to be left open or temporarily filled with guesses. New discoveries are almost daily turning up, inscriptions, texts, which unexpectedly here supply a missing link, there confirm or demolish a conjecture, establish or correct dates which had long been puzzles or suggested on insufficient foundations. In short, details may be supplied as yet brokenly and sparingly, but the general outline of the condition of Chaldea may be made out as far back as forty centuries before Christ.