Page:Popular Science Monthly Volume 11.djvu/39

Rh was constructed by Eupalinus, who had previously gained celebrity by building the aqueduct at Megara. At Athens the water-supply was drawn by subterranean conduits from Mounts Hymettus, Pentelicus, and Parnes, and received into reservoirs outside the city. Two conduits came from Mount Hymettus, and passed under the bed of the river Ilissus. Of course, it was necessary to supply fresh air to the water flowing through these subterranean channels, and that was done by piercing them with shafts at intervals of about fifty yards. Subterranean channels were also used to distribute the water through the city; they were of different forms, being round or square, and in some of them pipes of baked clay were laid. It is somewhat remarkable that these beneficent works were constructed by the wisdom of rulers who have come down to us branded as tyrants. The tyrants Theagenes of Megara, Polycrates of Samos, and Pisistratus of Athens, were the men who caused them to be built. Some of those old aqueducts still continue to supply Athens with water. The aqueduct of Syracuse which still supplies the city with an abundance of water, and which is remarkable for having a tunnel under the sea, between the city and the mainland, was built some time prior to the Athenian invasion, 412 B. C. for Thucydides mentions that it was partially destroyed by the invaders. But far more ancient than any yet referred to is the one at Jerusalem, built by Solomon, to conduct the water from the reservoirs, or "pools," that bear his name, to the city, a distance of six miles. It was formed by an earthen pipe ten inches in diameter, incased in stone and laid underground. It is still in use.

The periodical overflow of the Nile, the Tigris, and Euphrates, enabled the peoples of Egypt and Babylonia to store up vast quantities of water in artificial lakes, of which the Mœris in Egypt is a celebrated example, and the water was utilized as required, by surface-conduits or canals.

Let us now turn back to the aqueducts of Rome, and examine somewhat the details of construction. A recently-published work on the aqueducts comprehended in the archæology of Rome, by John Henry Parker, C. B., affords much interesting information in this connection. The facts are ascertained partly from the work of Sextus Julius Frontinus, who was superintendent of the aqueducts (curator aquarum) under the Emperors Nerva and Trajan (A. D. 94–107), and partly from explorations of the courses and remains of the aqueducts made by Mr. Parker himself. Of the eleven aqueducts already referred to, ten approached the city from the east and one from the west. Of the ten on the east, four had their sources near Subiaco, in a spur of the Apennines beyond Tivoli; the others took their rise in the lower lands nearer Rome. Two of these, the Anio Vetus and the Anio Novus, were fed by the river Anio, as is indicated by their names; the others received their waters from springs or small lakes,