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Subsidence along the Sea-coast of New Jersey. 347 



not necessary to specify them. Attention ia called to them now 

 as indications of a j^eriod of subsidence, and tlien one of eleva- 

 tion preceding the present 



The fossils, it will be perceived, are in circumstances which 

 require that the ground should have occupied a much lower 

 relative level than the presentj and the covering which is over 

 them is upland soil, — portions of that in New Jersey are in cul- 

 tivation, — and are among the most valuable and productive soils 

 m the state. While on the contrary the remains of trees, &c. 

 which are specially referred to in this paper are all as low as the 

 present level of high tide and are covered only by water or by 

 marsh mud and roots. They are also of a much more recent 

 date, some of them havincr been growinof trees within the mem- 



ory of persons now living, and the subsidence which has pro- 

 duced them is one that is still in progress as I wish now to show. 



In referring to the facts it will be convenient to follow the 

 same geographical order which has been observed before. 



Iq Elsinboro, on Delaware Bay, a portion of what is now tide 

 meadow was a heavily timbered maple swMmjD since the country 

 was iirst settled, and after this had died out and been replaced 

 by marsh there still remained in the midst of it a knoll or island, 

 as it is locally termed, of hard ground covered with timber. 

 N^ow this timber too is all dead, and the island is lost in the 

 marsh. The inhabitants say the tides run higher on the upland 

 than they formerly did. It manifestly is not caused by any 

 washing away of the soil. On Alloway's Creek there was a 

 considerable island in the unbanked marsh which was cultivated 

 for corn, w^heat, and other farm crops within the present century ; 

 but now it is overflowed by high tides, and is covered with 

 marsh mud and grass. A surveyor in extensive practice,* in 

 Cumberland Co. west of the Cohansey, informs me that there 

 are a number of such instances which have come under his own 

 observation. He referred me to one island of considerable size, 

 which in the early survey of the country is described and mapped 

 as being covered with timber. No timber is now to be seen 

 there, and the island is no longer upland. ^Its place is only as- 

 certained by sounding the marsh, when it is recognized by the 

 shallower deposit of mud and roots on it. Other instances of 

 the same kind were mentioned to me on the east of the Cohan- 

 s^y? of precisely the same character. 



The owner of an extensive tract of land between Maurice 

 I^iver and West Creekf informed me that within the last 50 

 years he had lost 1000 acres of timber,— by the tides running 

 higher on the upland than they formerly did. On Stipsons 

 Island I was shown portions of upland on which good crops of 



* Belford M. Bonham, Esq. t Joshua Brick, Esq. 



