There have been three periods of Semitic ascendency,--the era of the Assyrian and Babylonian empires; that of the Phoenician cities and of Carthage (a Tyrian settlement), with their colonies; and that of the Arabic-Mohammedan Conquests. This last epoch falls within the Christian era. In this course of Semitic history would be embraced the narrative of the Israelites, and of their dispersion in ancient and in modern times. The Indo-European, or Aryan family, follows next in order. In recording its history, we should consider, first, its oldest representative of which we have knowledge,--the Indian race, with its literature, its social organization, and its religions, Brahmanism and Buddhism. Then come the Persians, with their religion founded by _Zoroaster_, and the Armenians. With the fall of the Ancient Persian Empire, the center of power was transferred from Asia to Europe, where it has since continued, though still in the hands of the same Aryan race. The history of the Greeks and of the Romans succeeds; then the history of the three races,--the Celtic, Teutonic, and Slavonian,--as they present themselves at the threshold of authentic history. The forming of the several nationalities of Europe would have to be traced: the Slavonian, including Russia and Poland; the Teutonic, comprising England, Holland, Germany, and the Scandinavian peoples (viz., Denmark, Sweden, Norway, and Iceland); the Romanic or Italic nations (viz., Portugal, Spain, Provence, Italy, Wallachia, the Grisons of Switzerland), which are the nations the basis of whose languages is the rustic or people's Latin of the middle ages. Such, in brief outline, is the method which history, from the point of view of race affinities, as these are indicated by language, would adopt. UNITY OF DESCENT.--Whether mankind are all descended from one pair--the _Monogenist_ view, or spring from more than one center of origin--the _Polygenist_ view, is a question which philological science can not answer. The facts of language are reconcilable with either doctrine. While cautious philologists are slow in admitting distinct affinities between the generic families of speech,--as the Semitic and Indo-European,--which would be indicative of a common origin, they agree in the judgment, that, on account of the mutability of language, especially when unwritten, and while in its earlier stages, no conclusion adverse to the monogenist doctrine can be drawn from the diversities of speech now existing, or that are known to have existed at any past time. As far as science is concerned, the decision of the question must be left to zoölogy. The tendencies of natural science at present, as we have said above, are strongly toward the monogenist view. The variety of physical characteristics not only affords no warrant for assuming diversity of species among men; they do not even imply diversity of parentage at the beginning.