lower part of the city, has always been, more or less, brackish, owing to the percolation of the salt water from the north and east rivers through the loose sandy soil, thus giving them a distinct saline impregnation. The amount of impurities contained in these waters, varies, therefore, in different parts of the city, according to its elevation, and the denseness of the population. A gallon of water from the well belonging to the Manhattan Company in Reade-street, yielded 125 grains of solid matter ; while the same quantity of water, from their well in Bleecker-street, yielded 20 grains, and in 13th street, 14 grains. A gallon of water taken from four of the city wells in the densely populated parts of the city yielded on an average, 58 grains each of solid matter. The supply also of well water has been gradually diminishing in this city for the last several years. For example, at the Chemical Works on the North River, at 33d street, and at an extensive distillery on the East River, some distance above the Alms House, water cannot be procured in sufficient quantities on their premises,

where, but a few years past, it was obtained in great abundance. At the Gas Works on the Collect grounds, where they have a well 20 feet in depth, by 18 feet in diameter, which, until 1834, furnished water freely, enabling the engine to raise 20,000 gallons in ten hours, in 1835 it required 14 to 16 hours to raise the same quantity,