The Pauline Aqueduct, called _Aqua Paola_, is the third of the ancient works restored. The water is collected within the territories of Arcolo and Bassano, and conducted along the ancient Aqueduct of Alsietina. This was effected under Pope Pius V., and directed by Charles Fontana, an eminent Hydraulic Architect, who constructed the great fountain of S. Pietro-in-Montorio. Additional water was also taken from Lake Bracciano by Fontana in 1694, under Clement X. The whole quantity in 24 hours is 3,325,531 cubic feet, (20,285,739 gallons,) about one third of which goes to feed the fountains of St. Peters, and those of the Pontifical Palace on the Vatican Hill; the rest is distributed among 8 public and 23 other fountains, as well as to 21 work-shops, (_usines_) in St. Pancras-street. An evidence of the durability of these old Roman structures is furnished in this junction of water from Lake Bracciano by Cardinal Orsini, under authority of Clement X., upon condition that a part of the water should be used to feed a second fountain about to be built in St. Peter’s Square at Rome, and the rest to be divided between the Apostolic Chamber and the House of Orsini. From the lake the conduit leads to the old Alsietina Aqueduct, in which it flows 20 miles to the city, and it was found to be in so perfect a state when the trial was first made after the restoration, October 13th, 1693, that all the water which entered the old Aqueduct was discharged at Rome without any loss, after its use had been suspended nearly 1000 years. THE PRINCIPAL MODERN AQUEDUCTS OF ITALY, FRANCE, ETC. _Aqueduct of Caserta._ This Aqueduct was built by the order of the King of Naples, Charles III., for conducting water to his residence which he had at Caserta, a town situated about fifteen miles north of Naples. This Aqueduct was commenced in 1753. It is twenty-seven miles long, from the sources which supply it to the gardens of Caserta. The sources are at the base of the mountain called _Taburno_; the principal one is called _Sorgente de la Sfizzo_; it is afterwards joined by streams from many other sources, which are in the country called _Airola_. These waters are all joined in one Aqueduct, crossing the river _Faënza_, upon a bridge of three arches, built in 1753. Again, in the valley of _Durazzano_, there is another bridge of three arches, upon which the Aqueduct crosses the valley, passing over the river, and extending from the mountain called _Santa Agata de’Goti_, to the mountain of _Durazzano_.