Page:The American Cyclopædia (1879) Volume I.djvu/648

 612 AQUEDUCT and 4 ft. deep. The whole length was 70 rn. The ruin here illustrated is that of an arcade near Undena, composed of 1,000 arches, many of which were over 100 ft. in height. In its construction hydraulic cement was largely used, which is at present so solid that a single piece over 100 feet in length has fallen from the top without being broken. The ancient city of Mexico Avas supplied with water by the aqueduct of Chapultepec, built by Mon- tezuma, and carried across the lake upon a causeway. But no aqueducts, ancient or mod- ern, equal in length or in expense of labor those constructed by the incas of Peru. To irrigate their sterile soil, they brought water from the reservoirs of the mountains several hundred miles off. The aqueducts passed along the pre- cipitous sides of the Andes, penetrating some by tunnels worked through the solid rock with- out iron tools, and crossing chasms npon walls and arches of solid masonry. The conduit was constructed of large slabs of freestone, which were closely fitted together without cement. The works have long since fallen to ruins. The Romans, however, exceeded all other na- tions, ancient and modern, in the construction of these works. A treatise De Aquadvctibv* Urbis Itomce was written by the consul Sextus Julius Frontinus, who had the direction of the aqueducts under the emperor Nerva. He re- fers to nine different aqueducts, which brought into the city daily 28,000,600 cubic feet of pure water. The number of these was afterward increased to 24, some of which had several channels placed one above another, and extend- ing many miles. They were built on a grade of regular descent, winding around the hill? or penetrating them by tunnels, and in the low RuloB of the Aqua Claudia. levels supported on arches, which sometimes, as in the New Anio, extended for 6$ m. in one continued series, many of the arches more than 100 ft. high. The whole length of this aque- duct was over 63 miles. The Aqua Martia, which extended 38 miles, contained nearly 7,000 arches. The conduits were constructed in brick or in stonework laid in cement. There were numerous openings for ventilation and cisterns for collecting the sediment, in c<>ii-<-- quence of which the water was very pure. The Aqua Julia and Aqua Tepula were conveyed into the city upon the same structure, though at a higher level. The Aqua Claudia took its rise 38 m. from Rome, and approached it by a circuitous route, being led underground 36^m. and along 7 m. of cut stone arcades of sufficient height to supply the hills of Rome. The capacity of all the aqueducts was wonderful in proportion to the population. Strabo said that whole rivers flowed through the streets of Rome. It is esti- mated that 50,000,000 cubic feet of water must have been supplied daily to a population of 1,000,000, or about 312 imperial gallons to each individual. This is about ten times the supply from the three aqueducts at present in use. The Romans built other aqueducts also in their provinces, some of which exceeded in grandeur those which supplied the capital. That of Metis. (Metz) in Belgic Gaul is among the most remark- able. Extending across the valley of the Mo- selle, it conveyed the waters of the river Gorse to the city in such quantity that from it basins were filled in which mock naval engagements took place. The ruins of this great work still remain. There may also be cited the aqueducts of the island of Mitylene, of Antioch, of Sego- via in Spain, and of Constantinople. The aqueduct of Antioch was supplied from Beit el- Ma, 6 in. distant. The illustration given is that