ingly find this to be the case. Until within the last few years, the water on the elevated ground in Broadway, was considered to be the best in the city. In the progress of improvement, this water is now hard and unpalatable. Indeed, we know of families living above Broome-street, in Broadway, who are now supplied throughout the year by watew carts from the country and in the direction of Laurens-street, we have been informed that ;

MEMOIR OF THE this foreign supply is required still farther to the north of Broome-street. But we are now to allude to another cause, which must greatly impair the purity of our waters :

Into the sand bank, underlying the city, are daily deposited quantities of excrementitious matter, which, were it not susceptible of demonstration, would appear almost incredible. With our present population, there is put into this sand about 100 tons of excrement every 24 hours. In these deposites we may find all the ingredients detected by analysis, and which destroy the purity of our waters. But in this estimate we do not include an equal amount of urine, for the following reason This liquid, when stale or putrid, has :

the remarkable property of precipitating the earthy salts from their solution, or in other words, it makes hard waters soft. Although the fastidious may revolt from the use of water thus sweetened to our palate, it is perhaps fortunate that this mixture is daily taking place, for otherwise the water of this city would become, in a much shorter space of time than it actually does, utterly unfit for domestic purposes. We cannot take leave of this part of the subject without adverting to the various and contradictory opinions which have been expressed on the purity of our waters. We must impute to long use and the influence of habit, the opinion that our water is sufficiently pure for domestic purposes.