Among the Grecian states Corinth stood high in naval matters. Her people were expert ship-builders, and claimed the invention of the trireme, or galley with three tiers of oars. Athens, with its three ports, also carried on for a long period a large trade with Egypt, Palestine, and the countries bordering the Black Sea. The Romans had little inclination at first for seamanship, but were forced into it by their rivals of Carthage. It was as late as B.C. 261 before they determined to build a war-fleet, and had not a Carthaginian galley, grounded on the coast of Italy, been seized by them, they would not have understood the proper construction of one. Previously they had nothing much above large boats rudely built of planks. The noble Romans affected to despise commerce at this period, and trusted to the Greek and other traders to supply their wants. Quintus Claudius introduced a law, which passed, that no senator or father of one should own a vessel of a greater capacity than just sufficient to carry the produce of their own lands to market. Hear the enlightened Cicero on the subject of commerce. He observes that, “_Trade is mean if it has only a small profit for its object_; but it is otherwise if it has large dealings, bringing many sorts of merchandise from foreign parts, and distributing them to the public without deceit; and if after a reasonable profit such merchants are contented with the riches they have acquired, and purchasing land with them retire into the country, and apply themselves to agriculture, I cannot perceive wherein is the dishonour of that function.” Mariners were not esteemed by the Romans until after the great battle of Actium, which threw the monopoly of the lucrative Indian trade into their hands. Claudius, A.D. 41, deepened the Tiber, and built the port of Ostia; and about fifty years later Trajan constructed the ports of Civita Vecchia and Ancona, where commerce flourished. The Roman fleets were often a source of trouble to them. Carausius, who was really a Dutch soldier of fortune, about the year 280, seized upon the fleet he commanded, and crossed from Gessoriacum (Boulogne) to Britain, where he proclaimed himself emperor. He held the reins of government for seven years, and was at length murdered by his lieutenant. He was really the first to create a British manned fleet. In the reign of Diocletian, the Veneti, on the coast of Gaul, threw off the Roman yoke, and claimed tribute from all who appeared in their seas. The same emperor founded Constantinople, erected later, under Constantine, into the seat of government. This city seemed to be destined by nature as a great commercial centre; caravans placed it in direct communication with the East, and it was really the entrepôt of the world till its capture by the Venetians, in 1204. That independent republic had been then in a flourishing condition for over two hundred years, and for more than as many after, its people were the greatest traders of the world.