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350 Subsidence along the Sea-coast of New Jersey, 



cultiration of tlie ground, and that it ceases about buildings and 

 other structures. It will be perceived, however, that many of 

 the cases I have cited are of wood land which has been overrun 

 bj water before it was cleared. 



Prof Tuomej in his Eeport on the Geology of South Carolina 

 -efers to numerous facts to show that the opinion of a subsidence 

 of the coast of that state, originally advanced by Bartram in his 

 Travels, and since sustained by Lyell in Proc. GeoL Soc, vol. ii, 

 p. 406, is incorrect. He concludes that 'i there is not a single 

 instance of submerged swamp that cannot be traced to the en- 

 croachment of the ocean, without supposing any change in the 

 relative level of land and water on the coast. 



''Those writers who have referred them to the latter cause 

 erred in not having first studied the nature and level of the 

 swamps in which the trees grew whose stumps are found sub- 

 merged, and in not distinguishing tap-roots from true stumps.'' 



I do not think the cases to which I have referred are open to 

 this objection, as many of them were of upland forests and not 

 swamps at all. 



Prof. Hitchcock in a paper on the Geology of Portland and 



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vicinity, (Bost. Jour. Nat Hist., vol. i, p. 338,) and J. L. Hayes 

 Esq., before quoted, do not think the instances they have cited 

 are proofs of subsidence, but that they are only low lying swamp 

 origiually shut in from the salt water, but which by the wearing 

 away of the shores have been exposed to the action of the sea 

 which has washed out the muck and lowered the stumps. Such 

 an explanation would not apply to the cases of the islands which 

 I have mentioned or to those along the sloping shore. 



Mr. J. W. Dawson, in an article which I have before quoted^ 

 after mentioning a popular explanation connected with some 

 observations at the mouth of the Bay, but which he thinks 

 insufficient, says: "The only remaining mode of accounting for 

 the phenomena, is the supposition that a subsidence to the 

 amount of forty feet has occurred in the district. Such a subsi- 

 dence is not likely to have been limited to Fort Lawrence Point 

 and accordingly 1 have been informed by intelligent persons long 

 resident in the neighborhood that submerged stumps have been 

 observed at a number of other places in circumstances whicji 

 showed that they were in situ, and that trees and vegetable soil 

 have been uncovered in digging ditches in the marsh. Nor are 

 these appearances limited to Cumberland Basin. At the mouth 

 of Folly River, on the southern arm of the Bay, a submerged 

 forest on an extensive scale is said to occur, and in the marshes 

 at Cornwallis and Granville vegetable soils are found under the 

 marsh. These facts render it probable that the subsidence m 

 question has extended over the whole shores of the Bay, ana 

 that the marshes have been deposited, and the present lines oi 

 coo^t'CliiS cut, since its occurrence. 



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