The stream selected for the purpose of supplying the citizens, is the Piskawin Creek, and the distributing reservoir is

placed on its margin, about one third of a mile east of the city, and at an elevation of 100 feet above tide, and about 73 feet above the plain upon which most of the city buildings

82 PRELIMINARY ESSAY. are erected. The reservoir will hold about 1,900,000 gallons ; and the minimum supply of the creek at an unusually dry time, was 840,000 gallons per diem, which will allow 56

gallons per day to each soul, estimating the population at 15,000. The main, which first receives the water, is sixteen inches in diameter where it enters the reservoir, tapering down to twelve inches at the other end.The mains running through the several streets, vary from twelve to three inches in diameter, according to circumstances. It has been ascertained at Troy, that a 12 inch main, with a head of

73 feet, will discharge from the reservoir, and deliver into the city 1,500,000 gallons every twenty-four hours. The whole cost of the Troy Water Works, viz., for the purchase of land and water rights, building the reservoir, and laying the main pipes through the city, will amount to about $115,000. The annual expense of attending the works is but $800 ; five hundred to a superintendent, and three hundred to a clerk.

Providence, in Rhode Island, is partially supplied by an aqueduct, but on no very extensive scale.

Richmond, the capital of Virginia, derives water from the James river by works planned by Mr. Albert Stein, who was among the engineers originally employed to survey the courses of, and make estimates for, the Croton Aqueduct. An engine house 56 feet long and 58 wide, built of stone, on the banks of the river, cover two wheel pits and two pumps, constructed like those at the Fairmount works.