of overflowing fountains. The anarchy of the middle ages, as has been already stated, led to the destruction, among other works of art, of the aqueducts, and the Romans were again reduced to wells and springs, and the Tiber. A precarious supply of purer element had been occasionally obtained by repairing an ancient conduit — but neither the resources of the State, nor the skill of individuals, were equal to the undertaking of a permanent reparation. It was not until the pontificate of Nicolas V., that a restoration of an ancient aqueduct was attempted ; the Aqua Appia was then begun, and the work continued by Sextus IV., was completed by Pius IV., in 1568. At this period, the three channels by which water of the restored conduit arrived at 12 46 PRELIMINARY ESSAY. Rome, were conducted into, and distributed from, a reservoir without any architectural ornament. Clement XII. began its decoration on the side of the modern Palais ^Conti, from the designs of Nicolo Salvi. This beautiful monument and masterpiece of its author, was finished under Benedict XIV., and received the name of Trevi, from the water being conducted into its basin by three channels, and also from its position at the meeting of three streets. Of the three modern aqueducts, the Aqua Virgine, is accounted the most salubrious, and best adapted for culinary purposes. The pipes of this water are, on this account, sold at a higher price than the others. The aqueduct which furnished, at the time of Frontinus, 2,504 quinarice, (50,000 cubic feet,) now furnishes nearly 65,782 cubic metres in twenty-four hours, and this quantity is distributed by seven principal conduits into thirteen public, and thirty-seven common fountains. The present Aqua Felice, is part of the water of the ancient Aqua Claudia and Aqua Marcia, united with some other springs collected under the pontificate of Sextus V. The stream begins from the Campo Colonna, situated to the left of the Palestrina road, fourteen Roman miles from Rome, and enters the city through that remarkable ancient remain, called the monument of the Aqua Claudia. This water follows a course approaching to that of the Aqua Marcia and Aqua Claudia, but is on a lower level than either, as its sources are not so high up as the Anio. All the waters of which the Aqua Felice is composed, were united by Urban VII. in one immense reservoir, and several smaller ones, whence they were conducted into the conduit by an aperture named fistola urbana, formed in a block of marble. According to Fontana, this stream is equal to a hundred superficial « pouces d'eau." The quantity of water has been estimated at 20,537 cubic metres in twenty-four hours, distributed in sixteen public, and eleven common fountains. The fountain from which its water is distributed to the city, is adorned by a statue of Moses striking the rock, and two other figures, with four Ionic columns of granite, and two Egyptian lions of basalt, which formed part of the ancient decoration of the Pan- theon. Its name, Felice, is derived from Felice Peretti, which was that of the family of Sextus V. The Aqua Paola. — In 1694, the Cardinal Orsini, having proposed to the Papal gov- ernment to bring water from the Lake Bracciano (anciently Alsietinus) to Rome, in the ancient channel of the Aqua Alsietina, the architect, Paglia, examined the levels, and stated that a sufficient quantity of water could be obtained and directed into the channel as projected by the Cardinal. Permission was accordingly given to the Orsini family to commence operations, on condition of furnishing about a third part of the water for the supply of one of the new public fountains, and dividing with the apostolic chamber, th« revenue which would arise from the disposal of the remainder. PRELIMINARY ESSAY. 47 The cavalier Bernini, having the direction of the new fountain before St. Peter's and wishing to ascertain, by means which appeared to him less exceptionable than those employed by Abbe Paglia, whether the quantity which had been stated, as being at his disposal, could be obtained or depended upon, committed the examination of the levels to his brother, who gave his opinion against the practicability of obtaining that quantity which the Cardinal anticipated, on account of the small declivity of the channel of the aqueduct, and the variations in the levels of the lake itself. The Pope having directed new experiments and observations to be made, it was found that although the level of the lake was about one and a half palms above the surface of the ancient reservoir which fed the aqueduct, that this additional head was insufficient to produce the velocity to fur- nish the supply which was considered to be desirable. To obtain this velocity, a weir or