Moreover, this Roman Empire, like the Empire of the Achæmenidæ and the Russian State today, was geographically coherent; but it included no waste territory. All its possessions had some economic value and, apart from Britain, which was only apparently isolated, being attached to Gaul by kinship of population, all were borderers on or not far distant from the Mediterranean Sea. This was the centre about which the Empire was formed; all its shores had to be occupied, and as a matter of fact, from the time of Augustus Rome commanded the whole circumference. This attraction of an inland sea is remarkable. It does not mean that the Latin race really heard the call of the sea, for no instinct impelled them to navigate it. The Phœnicians and most of the Greeks felt as much at home on the water as on land; but the Roman was a landsman, and those of his poets who have celebrated Neptune and his train were only following Greek models. When barely full-grown and comparatively feeble, the Republic adapted herself to the peculiar conditions of that stern conflict which she was compelled to wage against Carthage. The naval art was, however, only in its infancy; no secrets of science had rendered it complicated, and Rome very soon provided herself with the indispensable ships of war. Nevertheless the issue of the great struggle was determined on land. So too was that of the wars against Greece; the sea merely providing, at the passage of the Hellespont, a vehicle for the troops which were to be engaged in Asia.