its springs, then I might say with propriety, it is infinitely too small for those uses. But ad- mitting, that at present it might be competent, the time will come, and that very shortly, from the growth of the city, when this source will most certainly be very inadequate to the demand. And again, supposing the pond to contain and furnish enough, it is a con- sideration well deserving attention, whether a pond, into which the filth from many of the streets must, without very great expense and care, be constantly discharged, and to which the contents of vaults, &c., will continually drain, is a desirable source from whence we should like to take water for drinking, cooking, &c., without taking into the account its noxious qualities, medically considered ; although it may be laid down as a general rule, that the health of a city depends more on its water, than all the rest of the eatables and drinkables put together." Mr. Weston, in like manner, says : — " It remains to examine the competency of the waters of the Collect. The general bias of opinion seems to lean in favor of this scheme ; 92 MEMOIROFTHE and if it can be made satisfactorily to appear, that the required supply can be obtained from this source, I am ready to allow that it is a work, that would be soonest accomp] ish • ed, and attended with the least expense. But we ought to be extremely cautious in ha- zarding an experiment, where the cost would be so great, and the event so doubtful. The question is of infinite importance, and unfortunately, one that cannot be determined by ab- stract reasoning. The capacity of the Collect, has been attempted to be proved, by its present extent ; but that, in my mind, is a most fallacious mode of reasoning ; for however great that may be, a powerful steam engine would soon exhaust it, unless replenished with numerous and copious springs. On these alone, therefore, it is evident we must de pend ; and I know of no other mode of estimating their combined effect, than by calcu- lating the quantity of water issuing from the outlet of the Collect ; which even at this time is so inconsiderable as scarce to deserve attention, and if my information is correct, it ceases to flow altogether in the summer. I am sensible that we should not too hastily conclude that the above is the total amount of the supply that may be derived from this source ; I think it very probable, that from the nature of the surrounding ground, (which is a coarse and porous gravel,) a considerable portion thereof, may percolate through, into the adjacent rivers. Much, and perhaps the greatest quantity, is also daily drawn off by the Tea- Water Pump ; which, from its vicinity, I have no doubt is supplied from the same source. It is true, that by sinking deeper into the earth, an augmentation of quantity would be procured ; yet if we went lower than the surface of the tide-water, I apprehend that the quality would be materially injured. Leaving the question, as I fear it will remain undetermined, we next proceed to examine the quality of the respective waters. To appreciate their merits fairly, we should judge of their utility, by the extent of their ap- plication. Proceeding on this ground, I believe it may be safely affirmed, that the water of the Bronx, is at least equal to that of the Collect ; though this is contrary to the gene- ral opinion. The only reason that I can perceive for the preference usually given to the last mentioned, arises solely from its superior coolness. However grateful this may be to our feelings, it does not follow that it is equally conducive to health ; for whatever degree of purity it may now possess, the period is not very remote, when from the natural increase of the city, these springs must be subject to those contaminations which have already rendered so many wells unfit for use, an evil that is daily increasing, and to which no ef- fectual remedy can be applied ; this to me has ever appeared an insurmountable objection. The idea of supplying a large city with pure water, from a reservoir in -its centre, has al- ways seemed very strange to me." The Bronx river was the source whence both Dr. Brown and Mr. Weston recommend- ed that the supply of water should be drawn. CROTONAdUEDUCT. 93 Dr. B., however, greatly underrated the quantity needed, and still more greatly, the expense of the work. He considered 362,800 gallons as an ample daily supply, and $200.000 as the utmost expenditure required for bringing the Bronx to the