500. The site of Rome itself was well supplied with water. Springs were abundant, and wells could be sunk to find water at no great depth. Rain water was collected in cisterns, and the water from the Tiber was used. But these sources came to be inadequate, and in 312 B.C. the first of the great aqueducts (aquae) was built by the famous censor, Appius Claudius, and named for him the Aqua Appia. It was eleven miles long, of which all but three hundred feet was underground. This and the Aniō Vetus, built forty years later, supplied the lower levels of the city. The first high-level aqueduct, the Mārcia, was built by Quintus Marcius Rex, to bring water to the top of the Capitoline Hill, in 140 B.C. Its water was and still is particularly cold and good. The Tepula, named from the temperature of its waters, and completed in 125 B.C., was the last built during the Republic. Under Augustus three more were built, the Jūlia and the Virgō by Agrippa, and the Alsietīna by Augustus, for his naumachia (§ 364). The Claudia (Fig. 2), whose ruined arches are still a magnificent sight near Rome, and the Aniō Novus were begun by Caligula and finished by Claudius. The Trāiāna was built by Trajan in 109 A.D., and the last, the Alexandrīna, by Alexander Severus. Eleven aqueducts then served ancient Rome. Modern Rome is considered unusually well supplied with water from four, using the sources and occasionally the channels of as many of the ancient ones. The Virgō, now Acqua Vergine, was first restored by Pius V in 1570. The springs of the Alexandrīna supply the Acqua Felice, built in 1585. The Aqua Trāiāna was restored as the Acqua Paola in 1611. The famous Mārcia was reconstructed in 1870 as the Acqua Pia, or Marcia-Pia.

   501. The channels of the aqueducts were generally built of masonry, for lack of sufficiently strong pipes. Cast-iron pipes the Romans did not have, lead was rarely used for large pipes, and bronze would have been too expensive. Because of this lack, and not because they did not understand the principle of the siphon, high pressure aqueducts were less commonly constructed. To avoid high pressure, the aqueducts that supplied Rome with water, and many others, were built at a very easy slope and frequently carried around hills and valleys, though tunnels and bridges were sometimes used to save distance. The great arches, so impressive in their ruins, were used for comparatively short distances, as most of the channels were underground.

   502. In the cities the water was carried into distributing reservoirs (castella), from which ran the street mains. Lead pipes (fistulae) carried the water into the houses. These pipes were made of strips of sheet lead with the edges folded together and welded at the joining, thus being pear-shaped rather than round. As these pipes were stamped with the name of the owner and user, the finding of many at Rome in our own time has made it possible to locate the sites of the residences of many distinguished Romans. In Pompeii these pipes can be seen easily now, for in that mild climate they were often laid on the ground close to the house, not buried as in most parts of this country.

   The poor must have carried the water that they used from the public fountains that were placed at frequent intervals in the streets, where the water ran constantly for all comers.

FIG. 326
THE PONT DU GARD, A ROMAN AQUEDUCT NEAR NÎMES