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from the shore line, vvliile the depth of the stratum under which 

 it flows, shows that it is overlaid by the mass of sea-water near 

 the shore. A continuation of solid marl stratum below the 

 water near the shore, would prevent any intermixture of the 

 alkaline water with the sea-water at that point, and allow it to 

 gradually mix only when the soundings are about twenty-five 

 fathoms. There is no cause apparent, which would prevent a 

 continued suspension of the minutely divided matter, until the 

 turbid water mixes with the sea-water. In the cases of pumping 

 referred to, the water, after some days, became more turbid than 

 at the commencement of the trials, leading to the conclusion 

 that turbid water occupied every part of the submarine channels 

 of flow. 



Proceeding to the more distant sources of this water, I have 

 resorted to chemical analyses of the waters from various points 

 in the vicinity of Boston, and the evidence that this water enters 

 the strata in the country back from the neighboring city of 

 Charlestown, is almost conclusive. Many of the open wells of 

 that city contain a clear water, having bicarbonate of soda in 

 excess over the earthy salts also contained in it, and I have found 

 that the argillite and clay beds contain sulphates of lime and 

 soda, as well as silicates of soda and potash. At a future time, 

 I shall place before the Society the experimental demonstrations, 

 which render these facts relating to the presence of the sulphates 

 in the argillite palpable to the eye ; remarking here, that the 

 well understood decompositions and recompositions explain, in a 

 simple manner, the production of bicarbonate of soda or potash. 

 The occurrence of fresh water forced up from below the 

 ocean, along the border of our Southern States, has been fre- 

 quently described. I have observed phenomena in several places 

 among the West India Islands, illustrating this flow from the 

 land under the water of the ocean, where the elevation of vol- 

 canic mountains was considerable. 



The mere presence of fresh water at the bottom of the ocean 

 infiltrating through the slime, or sand, would be sufficient to 

 induce chemical changes by the disturbance of electrical rela- 

 tions. While the surface and mass of the ocean water, absorb- 

 ing oxygen from the air, would be positive to a stratum of sea- 



PROCREDTNGS R. S. N. H. VOL. V. 13 JTTLY, lS?i.=i. 



