AQUEDUCT, an artificial channel or conduit for the conveyance of water from one place to another; more particularly applied to structures for conveying water from distant sources for the supply of large cities. Works for supplying com munities with water must have been con structed at a very early period. In China there are said to be aqueducts dating back to prehistoric times. In Persia and Assyria there are structures the remains of which indicate that they were used for aqueducts. Recent ex cavations at Jerusalem have laid bare wells and channels cut in the solid rock, it furnished 277,866 cubic meters a day; it was not used for drinking, but for irrigating gardens and flushing drains. In 144 B. C. the Senate determined to and indicate that the water supply of the city was brought from the neighborhood of Bethlehem and Hebron. In Patara, a city of Lycia, in Asia Minor, there is a very ancient aqueduct, consisting of an embankment of rough stone 250 feet high and 200 feet long. The channels for the water consist of cubical stone blocks about a yard in dimension, with a hole 13 inches in diameter, the blocks being closely connected and cemented to gether. The first Roman aqueduct was the joint work of Appius Claudius Cactus and Caius Plautius Venox, censors in 312 B. C. Appius Claudius built the con duit, Venox discovered the springs. The entire length of the aqueduct was about 10 miles, and it furnished 115,303 cubic meters a day. The second aqueduct was begun in 272 B. C., by Manius Curius Dentatus, and was finished three years later. Its length was about 45 miles, and repair the old aqueducts and built a new one. This work was begun by Quintus Marcius Rex. The Marcian aqueduct brought the water from 56 miles away in the territory of Arsoli, and fed water to the highest platform of the capitol. It was restored in 33 B. C., and Augustus doubled the supply of water in 5 B. C. The viaducts and bridges by which it crossed the highlands are magnificent. There are seven bridges, some of them carrying four aqueducts. The Marcian reaches Rome at the Porta Maggiore, where no less than 10 water supplies met. Of the nine aqueducts which brought water to ancient Rome, three still supply the modern city, viz., the Aqua Virgo, now Acqua Vergine, finished by Agrippa, 27 B. C., and restored by Pope Nicholas V. in 1453; the Aqua Trajana, now Acqua Paolo; and the Aqua Marcia.
The Romans also constructed impor tant aqueducts for the cities throughout their empire. One of the finest aque ducts in Europe is the Pont du Gard, built in the 3d or 4th century, or pos sibly by Agrippa, 19 B. C., at Nimes, in southern France. It is still in a good state of preservation. It is higher than any about Rome itself, being fully 180 feet in height, and the length its highest arcade is 873 feet. There is an aqueduct in Paris built by Julian in 360 A. D. ; also a very important aqueduct at Constantinople, built by Hadrian and re stored by Theodosius. Since 1885 the water has been furnished the city by an aqueduct built by a French company, taking the supply from Lake Derkos.
The ruins of an aqueduct exist at May ence, and of another near Metz, Alsace Lorraine.
There are many other important aque ducts. One of the most remarkable is that constructed by Louis XIV., in 1684, to convey the waters of the Eure from Point Gouin to Versailles. Troops to the number of 40,000 were employed in this great undertaking. The bridge at Main tenon, forming part of this aqueduct, even in its incomplete state, is, in point of magnitude, the grandest structure of the kind in the world. The remains con sist of 47 arches, each 42 feet wide and 83 feet high. The piers are 25 feet 6 inches thick.
The first important aqueduct in Eng land was built in 1613, to conduct the waters of the New river to London, over a distance of 20 miles. Wooden aque ducts were first used, but were replaced by embankments. Very large works were constructed during nine years, end ing in 1877, to bring water from Long dendale, between Sheffield and Manches ter, to the latter city. In this instance the aqueducts consist for the most part of tunnel and covered conduit, but for 8 miles the water is conveyed in large cast-iron pipes laid along or under the public roads. Before the Longdendale works were finished, the question of a greater supply had to be considered. This led to the adoption of the scheme for bringing water from Lake Thirlmere in Cumberland to Manchester. The length of the line is nearly 100 miles, and the works were carried out in 1885-1894.
In Scotland, the Loch Katrine aque duct supplies Glasgow with water coming from a distant of 42 miles. An aqueduct was built in 1738, conducting water for a distance of about 15 miles into the city of Lisbon. The aqueduct of Caserta was built in 1573, by Vanvitelli, by order of Charles III. and his son, for the pur pose of supplying the gardens of Caserta with water from Monte Taburno, a dis tance of 25 miles. It now conducts the water to Naples and crosses 20 valleys; the last 15 miles the water is carried ill iron piper,. The Canal de Marseilles, 57 miles in length, conveys water from the River Durance to Marseilles, and is a magnificent specimen of French engi neering. The Vienna aqueduct is nearly 60 miles long, and was finished in 1873.
There are a number of important aque ducts in America. For 125 years, the city of Otumba, in Mexico, received its supply of water through the aqueduct of Zempoala, which, however, has not been used since 1700, though the aqueduct is said to be in almost perfect condition. It is 27 miles long. New York is supplied with water from Croton river, which falls into the Hudson above Sing Sing. The first aqueduct was constructed between the years 1837 and 1842, and is 38 miles long. When the conduit reaches the Harlem river, the water is conveyed in iron pipes over a splendid bridge, 150 feet above the river.
In October, 1917, New York celebrated the completion of the vast Catskill Aque duct. The great Ashokan Reservoir, 12 miles west of Kingston, N. Y., receives the waters which supply New York City with from 500 to 600 million additional gallons of water per day.