ranean, as they have been in the Great War, that condition of things is in efEect realised so far as human movements are concerned.
The Roman Emperors put their Eastern capital at Constantinople, midway between the Danube and Euphrates frontiers, but Constantinople was to them more than the bridge-town from Eiurope into Asia. Rome, the Mediterranean Power, did not annex the northern shore of the Black Sea, and that sea, therefore, was itself a part of the frontier of the Empire. The steppes were left to the Scythians, as the Turks were then called, and at most a few trading stations were dotted by the seamen along the coast of the Crimea. Thus Constantinople was the point from which Mediterranean sea-power held the middle sea-frontier, as the land-power of the Legions held the western and eastern frontiers along the rivers. Under Rome, sea-power thus advanced into the Heartland, if that term be understood, in a large, a strategical sense, as including Asia Minor and the Balkan Peninsula.
Later history is no less transparent to the underlying facts of geography, but in the inverse direction. Some of the Turks from Central Asia turned aside from the way down into Arabia, and rode over the Median and
