Geology of Hudson County, JVcw Jersey. 51 



sheet of drift is spread over all the highlands, and covering the 

 hill-sides, dips beneath the more recent sand-dunes and salt- 

 marshes along the Newark Bay on the west, and bordering the 

 New York Bay on the east. This drift consists mainly of 

 broken and disintegrated red sandstone and shale, derived from 

 tlie Triassic area to the westward, and gives the prevailing red- 

 dish color to the soil. It also contains numerous boulders, fre- 

 quently four or five feet in diameter ; some of these are of trap, 

 doubtless derived from the hill itself ; others are of metamor- 

 phosed slate, the parent beds of which j)robab]y overlie the trajj 

 on the western slope of the hill ; with these are mingled many 

 masses of Triassic sandstone that could only have come from 

 the region covered by that formation to the westward ; there are 

 also other erratics in less numbers, composed of gneiss, quartzyte, 

 conglomerate, etc., — rocks that are found in place only in the 

 Highlands of New Jersey, at least thirty miles west. When 

 these transported boulders are examined more closely, we find 

 many of them worn and rounded, and like the trap beneath, 

 showing smoothed and sci'citched surfaces. Although the drift 

 covers nearly the whole of the county, yet it accumulated most 

 abundantly along the eastern side of Bergen Hill, under the lee 

 of the trap-ridge ; for the glaciers came from the northwest. 

 The boulders are also especially noticeable where the finer ma- 

 terial has been carried away, either naturally or for purposes of 

 improvement, as in some of the squares at Lafayette, in the 

 Elj^sian Fields, etc. Another good exposure of the drift is to be 

 seen along the line of the N. J. Central Eailroad at Bergen 

 Point ; here the drift is overlaid by blown sand. 



Over Hudson County, the glaciers were of great thickness, and 

 flowed towards the southeast with such force that the trap-ridge 

 of Bergen Hill could not deflect them from their course. The 

 long parallel scratches and grooves on the rocks, as well as the 

 nature of the transported boulders, show that the ice moved 

 from the northwest obliquely across the ridge. Throughout 

 Long Island, on the northern border of Staten Island, and in 

 an irregular line of hills crossing New Jersey near Plainfield, is 

 the terminal moraine deposited by these ancient glaciers. 



To one familiar with existing glaciers, and the records that 

 they leave on the rocks over which they move, nothing is easier 



