Below their confluence with the Anio, the yellow waters of the Tiber, discoloured by the clay brought down from the plains of Umbria, rush beneath the bridges of Rome. Soon afterwards the river winds round the last hills, which formerly bounded an ancient gulf of the sea, now silted up. The influence of the tides makes itself felt. At the head of the Sacred Island, formerly dedicated to Venus, and famous for its roses, but now a dreary swamp, covered with reeds and asphodels, it bifurcates. The principal branch, the old Tiber, passes to the south of this island. Ostia, which was the port of the river during the early days of Rome, is buried now beneath fields of cereals and thistles, at a distance of five miles from the sea. Excavations made there since 1855 have laid bare several temples, tombs, and warehouses. The merchants of Rome were compelled to abandon that city two thousand years ago, on account of a bar formed at the mouth of the river. The Roman emperors, anxious to have an outlet into the sea, ordered a ship canal to be excavated to the north of Ostia. This is the Fiumicino, which the erosive action of the Tiber has converted into a small river. Claudius had huge docks excavated to the north of this canal, and a new Ostia arose near them. Trajan opened another port to the south-east of it, which remained for several centuries the port of Rome. But it, too, has been silted up for about a thousand years, and the alluvium brought down by the Tiber is continually encroaching upon the sea, the rate of progress being about three feet annually at the mouth of the Fiumicino, and ten feet at that of the old Tiber. Extensive ruins of palaces, baths, and storehouses exist near the ancient port of Trajan, and several works of art have recently been excavated there. The mouth of the Tiber is thus closed by a bar, like that of all other rivers which flow into the Mediterranean; and the Romans, instead of being able to make use of their river for communicating with the sea, are obliged to have recourse to more distant harbours. In former times they kept up this communication with Sicily, Greece, and the Orient through Antium, Anxur (Terracina), and even Puteoli; but since the countries of the North have risen into political and commercial importance, Cività Vecchia has become the great maritime entrepôt of the valley of the Tiber. It is well known that Garibaldi has conceived the stupendous project of converting Rome into a great maritime city. The stagnant waters of the Campagna are to be carried off by means of a huge sanitary canal, the bed of the Tiber is to be deepened, and an artificial harbour capable of receiving the largest vessels is to be constructed far out in the Mediterranean. {274}