For similar reasons, the inhabitants of Europe each year tend to more complete homogeneity. Climate and meteorological differences are more and more perfectly equalized by artificial inventions; nor is it alone a similarity of habits, a similarity of physiological constitution also ensues. The effect of such inventions is to equalize the influences to which men are exposed; they are brought more closely to the mean typical standard, and--especially is it to be remembered--with this closer approach to each other in conformation, comes a closer approach in feelings and habits, and even in the manner of thinking. [Sidenote: The Mediterranean peninsulas.] On the southern slope of the mountain axis project the historic peninsulas, Greece, Italy, Spain. To the former we trace unmistakably the commencement of European civilization. The first Greeks patriotically affirmed that their own climate was the best suited for man; beyond the mountains to the north there reigned a Cimmerian darkness, an everlasting winter. It was the realm of Boreas, the shivering tyrant. In the early ages man recognized cold as his mortal enemy. Physical inventions have enabled him to overcome it, and now he maintains a more difficult and doubtful struggle with heat. [Sidenote: The Mediterranean Sea.] Beyond these peninsulas, and bounding the continent on the south, is the Mediterranean, nearly two thousand miles in length, isolating Europe from Africa socially, but uniting them commercially. The Black Sea and that of Azof are dependencies of it. It has, conjointly with them, a shore-line of 13,000 miles, and exposes a surface of nearly a million and a quarter of square miles. It is subdivided into two basins, the eastern and western, the former being of high interest historically, since it is the scene of the dawn of European intelligence; the western is bounded by the Italian peninsula, Sicily, and the African promontory of Cape Bon on one side, and at the other has as its portal the Straits of Gibraltar. The temperature is ten or twelve degrees higher than the Atlantic, and, since much of the water is removed by evaporation, it is necessarily more saline than that ocean. Its colour is green where shallow, blue where deep. [Sidenote: Secular geological movement of Europe and Asia, and its social consequences.]