The victories of the Romans achieved the grand project which had been first conceived by the genius of Alexander. The numerous and distant nations comprehended within the wide limits of the Roman empire communicated together as members of the same great body, and learned to estimate the advantages of mutual intercourse. The work of union was promoted by the dares of a vigilant and liberal administration. Great roads were constructed traversing the empire in all directions; a common language was diffused; and, in short, the chief obstacles, both natural and moral, to the easy and intimate correspondence of foreign nations, were either totally broken down or rendered much less insurmountable. How far the growth of the imperial power and the gradual extinction of liberty in the Roman world, was connected with the decline of literature and the arts, or whether the extension of the Roman power was conducive to the civilisation of mankind, are questions which lie beyond the compass of this work. But certain it is that the causes, whatever they were, to which we must ascribe the general declension of taste, did not at all impede the progress of geography. This science, depending for its growth almost wholly on the accumulation of facts, continually profited from experience, unaffected by the sinister influence of political corruption; and its progress appears to have been particularly rapid between the Augustan age, when Strabo wrote, and that of the Antonines, in which Ptolemy flourished, and when the Roman empire was already on the verge of decay.