The horizontal dimensions supply most of the material for our elementary compends for political geography, which seldom make much account of vertical dimensions, and which, by no means, penetrate to their real value. They are commonly held to be a side-matter, to be touched lightly upon, or wholly cast aside. But both must be thoroughly studied; for they are mutually dependent, and are never found divorced in nature. In order to understand them in their true relations, we will look at them in their general aspect, discussing first the horizontal extent of the continents, then their vertical elevation, so far as that has not already been treated. After this twofold investigation, the character of each continent and its subdivisions will appear in its true light. On account of the importance of thoroughly understanding the articulation of great districts, in contradistinction to a mere division, which implies no organic and living correlation of parts, and which gives over to mathematics, political history, and fortuitous circumstances the duty of explaining geographical phenomena, it is instructive to trace the footsteps of our science back to some of the earlier conceptions. Eratosthenes and Polybius were aware that the south of Europe was a series of peninsulas, the first of the two speaking of the great peninsulas of Spain, Italy, and the Peloponnesus, the latter adding allusions to the smaller Grecian peninsula of Sunium, the Thracian on the Bosporus, and the Tauric Chersonesus, now known as the Crimea. Strabo got a clearer insight into the significance of these forms, (whose meaning Hipparchus had already tried to explain,) by discussing them according to the sea basins which they separate. Thus the Spanish peninsula separates the Gulf of Cadiz, at the Pillars of Hercules, from the Tyrrhene Sea; Italy separates the Sicilian Sea from the Adriatic; the Peloponnesus separates the Adriatic and the Euxine. This view, though apparently simple, was really profound; for it hinted at the great significance of the maritime coast in developing the civilization of those countries. And Strabo goes on to add that Italy, with its southeastern and southwestern extremities, becomes too pointed, (δικόρυφος,) and that the eastern peninsulas of Europe are much more jagged and articulated (ποικίλαι καὶ πολύμερεῖς) than Polybius had conceived them to be. He entered, therefore, upon a more minute subdivision. Strabo had already (ii. 92) called the Peloponnesus “many-parted,” (πολυ σχεδές,) as the Laconian peninsula (Tœnarum) is separated from Malea, the Attic from Sunium, and all southern Europe cannot, therefore, be laid out in six parts. Of the north of Europe, Strabo was not in a position to gain any accurate conception. Toward the end of his second book, where he gives his reason for beginning his description at the West, he uses the awkward but significant phrase “polymorphous formation,” to indicate the superiority which Europe