174 On the Cause of Fresh Water Springs, Fountains, fyc. 



Art. XXV. — On the Cause of Fresh Water Springs, Foun- 

 tains, <^c; by Joseph Du Commun. 





In the Harmony Gazette, November 21, 1827, there is a 

 Nut for the philosophers, picked, it is said from the National 

 Gazette. I have endeavored to crack it, and I now present 

 you with the kernel, leaving to your taste to determine 

 whether it is palatable. 



The questions proposed are two in number, 1st, Why the 

 fresh water issuing from the depth of two hundred and twenty 

 feet, by boring in solid rock near the city of New Brunswick, 

 rises from eight to fourteen feet above the surface of the Rari- 

 tan river ? and 2d, Why the quantity of water corresponds 

 exactly and continually with the rising and falling of the tide ? 

 If we take an inverted glass syphon ACB 

 and pour water into it, the two sides will be 

 filled in part, and the water will rise in each 

 i\\ side to the same height, say a and 6. 



If instead of water, we introduce mercury in 

 the branch A and rain water in the branch B, 

 one inch of mercury at m will support above 

 thirteen inches of water in the branch B. 

 \ And lastly, if in the branch A we have a 

 fluid denser than common water, as salt wa- 

 ter for instance, the column of fresh water 

 will be supported in the branch B, at the 

 height b, by a column of the salt water infe- 

 rior to it in height, in the inverse ratio of their 

 densities, say to the height c only. 



But now, cannot the branch B, of our sy- 

 phon represent the subterranean stream wind- 

 ing through the crevices of the rocks, until it 

 C reaches, at some depth or other, the great 



oceanic reservoir, and cannot the column of salt water in 

 the branch A represent, in like manner, the height and press- 

 ure of the salt water of the ocean ? 



If so, it explains why the fresh water, in boring by the sea 

 shore, is raised and flows above the level of the sea water : 

 thus, one of the two given questions seems, to be solved. 



The answer to the second may be deduced from the same 

 principle. 



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