As we trace the increasing volume and extent of commerce from the days of Tyre and Carthage and Alexandria to its fullest development under the empire, and remember that as the drafts of luxury-loving Rome upon the products of the east, even of China and farther India, increased, the true knowledge of the form of the earth, and the underestimate of the breadth of the western ocean, became more widely known, the question inevitably suggests itself, Why did not the enterprise which had long since utilized the monsoons of the Indian Ocean for direct passage to and from India essay the passage of the Atlantic? The inquiry gains force as we recall that the possibility of such a route to India had been long ago asserted. Aristotle suggested, if he did not express it; Eratosthenes stated plainly that were it not for the extent of the Atlantic it would be possible to sail from Spain to India along the same parallel;[313] and Strabo could object nothing but the chance of there being another island-continent or two in the way,—an objection unknown to Columbus. Seneca, the philosopher, iterating insistence upon the smallness of the earth and the pettiness of its affairs compared with the higher interests of the soul, exclaims: “The earth, which you so anxiously divide by fire and sword into kingdoms, is a point, a mere point, in the universe.... How far is it from the utmost shores of Spain to those of India? But very few days’ sail with a favoring wind.”[314] Holding these views of the possibility of the voyage, it is improbable that the size of their ships and the lack of the compass could have long prevented the ancients from putting them in practice had their interest so demanded.[315] Their interest in the matter was, however, purely speculative, since, under the unity and power of the Roman empire, which succeeded to and absorbed the commercial supremacy of the Phœnicians, international competition in trade did not exist, nor were the routes of trade subject to effective hostile interruption. The two causes, therefore, which worked powerfully to induce the voyages of Da Gama and Columbus, after the rise of individual states had given scope to national jealousy and pride, and after the fall of Constantinople had placed the last natural gateway of the eastern trade in the hands of Arab infidels, were non-existent under the older civilization. It is certain, too, that the ancients had a vivid horror of the western ocean. In the Odyssey, the western Mediterranean even is full of peril. With knowledge of the ocean, the Greeks received tales of “Gorgons and Chimeras dire,” and the very poets who sing the beauties of the Elysian or Hesperian isles dwell on the danger of the surrounding sea. Beyond Gades, declared Pindar, no man, however brave, could pass; only a god might voyage those waters. The same idea recurs in the reports of travellers and the writings of men of science, but here it is the storms, or more often the lack of wind, the viscid water or