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 hazarding 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 abstract 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 calculating 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 coarseand 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.