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NEW YORK STATE MUSEUM 



this is sometimes made up quite largely of a sand or clay sedi- 

 ment. In the wooded portion the thickness of the peat increases 

 very rapidly, and about a half mile from the river the clay was 

 not reached till 17 feet of good peat was bored through. The 

 thickness of the deposit at various points is as follows : 



Pine island 



18 feet 



bottom not reac 



Black Walnut island 



18 feet 



a 



i m. west of Durandville 



16 feet 



clay underneath 



IJ m. west of Durandville 



17 feet 



a 



4 m. west of Big island 



12i feet 



bottom not reac 



1 m. west of Big island 



121 feet 



a 



Florida 



18 feet 



u 



A fair average of the depth would probably be about 18 feet, 

 though many places are reported, on questionable authority, to 

 have a depth of 50 feet. The quality of the peat from the sur- 

 face to the underlying clay is apparently very uniform. Except 

 near the river bank, no sand is to be detected, and the clay 

 beneath it is very fine grained. A slight amount of sand is to be 

 noticed in the clay in some places, though ordinarily it is re- 

 markably free from grit. The small quantity of marl present 

 is somewhat surprising, as about 2 inches of marly peat just 

 above the clay are the only trace of its existence. From the 

 fact that all classes of vegetation are present on the surface of 

 the deposit, and that borings bring up nothing but pulpy peat 

 and decomposed wood from all depths, it is readily seen that 

 there has been no great change in the general type of vegetation 

 in this place since the lake-filling process started. So far as 

 the materials which form the peat are concerned, this deposit 

 would hardly come under any of the classes of peat deposits 

 given by Wagner, but would be rather a composite deposit. 



Because of the great thickness and the jellylike consistency of 

 the deposit, the quaking of this bog is more pronounced than in 

 shallower deposits, which are underlain by marl. When a carriage 



