January, .737 1,712,198 11,264 February, .796 1,479,878 9,736 March, 1.070 2,237,242 14,719 April, .814 566,861 3,729 May, 1.462 387,974 2,552 June, .964 88,282 581 July, 1.077 51,110 336 August, 1.251 30,202 199 September, 1.015 46,464 305 October, 1.076 989,976 6,572 November, .937 2,176,838 14,321 December, .801 2,604,307 17,133 The city of Brooklyn gathers its supply by intercepting ponds. The source is the southern slope of Long Island, with a drainage area of 60.25 square miles. The plain is composed of fine sand, which is saturated with excellent water, the surface of which rises twelve feet per mile from the tide level at the shore, and which appears at the surface of the ground in springs and streams, where depressions occur in the ground level. The minimum observed flow occurred in 1880, and was equal to 9.4 inches on the water-shed. The available supply is, at times, quite small. The city of Lynn uses a driven well partly, of which they say, in their annual report for 1880: “The doubtful character of any underground supply of water, especially when it is drawn from beneath a territory occupied by a densely settled community, makes frequent examination of its quality a duty not to be disregarded. We invite attention, however, to the fact that the chemical examination of the well water has shown an increasing quantity of foreign matter mingling with it as pumping proceeded, and that this increase suggests an inflow of water to the wells from some other source than that from which it was at first drawn.” This method of securing water, however, is largely resorted to in the origin of water-works for small cities. The Sanitary Engineer (Vol. v, No. 5) refers to a proposed well for Lincoln, Nebraska, a town of 15,000 inhabitants, that the contractor proposed to dig for the sum of $10,000. The estimated capacity will be ten million gallons a day, and the editor of the paper observes: “If a large well is sunk in a very saturated and porous soil, it will probably furnish the amount required for the city (one million gallons) at first, possibly a great deal more. But in five years’ time it is not hazardous to predict that such a well will not yield enough water for Lincoln. As for furnishing ten million gallons a day for any length of time, there is no well in the world, which we know of, of such a capacity, and all experience is against the probability of such an one being discovered.” GRAVITATION