largest public fountain is in the square fronting the palace, and close to the harbor. This supplies the shipping, and it is constantly surrounded by sailors of all nations. Captain Cooke expressed doubts about the goodness of the water for long voyages ; but Dr. Von Spix, a Bavarian traveller, who visited Brazil in 1818, states, that it had been conveyed to India and back, and found un- corrupted. The supply of water from this source and all others, is spoken of as scanty, for such a population ; but no account is given of the quantity. In the United States, as earliest and grandest in design, we mention the Water Works of Philadelphia. The first water works were commenced in 1799, (the year in which the Manhattan Company was incorporated for supplying New- York with water,) and consisted of forcing pumps, worked by steam engines, which raised the water from the Schuylkill into a reservoir, constructed at an elevation of fifty feet on the banks of the river, from which it was conveyed to the city in wooden pipes. In 1811 the city councils appointed a com- mittee to devise means for procuring a more perfect supply than those in use afforded ; and shortly after, two steam engines and pumps were established at Fairmount, another point of the Schuylkill, about two and a half miles from the city. A reservoir 318 feet in length, 167 in width, and 10 in depth, was made at an elevation of 98 feet, into which the water was forced from the river by the engines and pumps. The great expense attending this mode of raising the water, caused the city authorities to cast about for some more economical, as well as effective, expedient, and accordingly in 1819, a contract was made with Capt. Ariel Cooly, for damming the Schuylkill. For the sum of $150,000, he undertook to throw a dam of sufficient height across the river to create the requisite head of water, to construct the locks and canal for the accommo- dation of the navigation, to build the head arches of the race-way for the water power, and to excavate the race out of the solid rock. The whole length of the dam, including the * Notes on Rio de Janeiro, by Jno. Luccock, 1820. PRELIMINARY ESSAY. 77 head arches, and the water pier, exceeds 1600 feet, and it backs the water up the river about six miles. By the water power thus created, operating upon eight wheels and pumps, it is estima- ted that ten million gallons may be daily thrown into the reservoirs; the flow of the river in dry seasons was supposed to be 440,000,000 gallons in the 24 hours, and allowing for leakage, wastage, &c. it is calculated that 40 gallons upon the wheels will raise one into the reservoir — which would give a result of 11,000,000 gallons a day. " On the east side of the river, the whole of the bank was a solid rock, which it was necessary to excavate to the width of one hundred and forty feet, to form a race as a site for the mill houses running parallel with the river. The length of the mill race is four hundred and nineteen feet, the greatest depth of excavation sixty feet, and the least six- teen feet. The gunpowder used, alone cost the contractors upwards $ 12,000. At the upper part of this excavation were erected the head arches, three in number, which extend from the east end of the mound dam, to the rock of the bank, thus forming a continua- tion of the dam. " On the west of the excavation are erected the mill houses, forming the west side of the race, which is supported on the other side by the rock, rising above it seventy or eighty feet perpendicular. The south end of the race is also of solid rock, and the mill houses are founded on rock, so that nothing can be contrived more secure in all respects. The race is about ninety feet in width, and is furnished with water through the head arches, which allow a passage of water sixty-eight feet in breadth, and six feet in depth, to which the race is excavated below the overfall of the dam, and of course, room is allowed for a continual passage of four hundred and eighty square feet of water ; these arches are on the north of the race, and the mill buildings being on the west, the water passes from the race to the wheels which discharge the water. The mill buildings are of stone, two hundred and thirty-eight feet long and fifty-six feet wide ; the lower section is divided into twelve apartments, four of which are intended for eight double