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obtained almost on the surface. The same fact was observed on 

 Sandy Neck, a long sand peninsula, which separates Barnstable 

 Bay from Barnstable Harbor, and at Provincetown. At the for- 

 mer place, it is particularly striking, as good water is very 

 scarce in the town of Barnstable, on the main land directly 

 opposite. In this town is a well, about one hundred and fifty 

 feet from the shore, in which the water rises and falls with the 

 tide, although only through a space of one foot and a half. 



As yet, Mr. Cabot had not been able to satisfy himself whether 

 the amount of rise and fall in wells showing this sympathy with 

 tidal fluctuations, depends upon their distance from the salt water 

 or not. Since making these observations he had noticed that 

 such a rise and fall is not limited to wells in a natural formation. 

 He had observed that in loose deposits of an artificial character, 

 in the vicinity of salt water, they also occur. Thus, in Suffolk 

 street, which is laid out on newly-made land, this fluctuation 

 takes place in the wells ; and in some trenches which he had 

 caused to be dug recently in Charles street, for the foundation of 

 a building, at high tide fresh water makes its appearance, while 

 at low tide they are empty. An interesting inquiry suggests 

 itself as to the origin of these deposits of fresh water in such 

 loose soil. They cannot be derived from springs, for these occur 

 distinct from them, in the same formations, and present peculiar 

 characters of their own ; often bubbling out from the surface of 

 the sand, even below the line of high water on beaches. It might 

 be supposed that they are the result in part of a filtration of the salt 

 water through the sand. To test this, Mr. Cabot poured a quan- 

 tity of salt water through sand, and found that it lost two per 

 cent, of its specific gravity ; a curious and unexpected result, but 

 not sufficient fully to explain the case. On the whole, he was 

 inclined to accept the opinion of Mr. Mather, that these sup 

 plies of fresh water are derived from rains, and are pre 

 vented from oozing out laterally, by the pressure of the neigh 

 boring salt water. ' As this advances, it recedes, and its leve 

 rises ; as the tide goes out, it follows, and its level is depressed 

 The practical result from these investigations is, that it will un 

 doubtedly be found that in all deposits of sand like those exam 

 ined by Mr. Cabot, an abundant supply of fresh water may be 

 obtained at all times ; a fact of great importance to mariners. 



