50 Geology of Hudson County, New Jersey. 



concentric with it, occurs tlie First NeAvark Mountain, also a 

 crescent or " canoe-sliaped " ridge of trap. Scarcely half a mile 

 westward of this is the Second Newark Mountain; and westward 

 of this, again, is a fourth range of trap, much less regular than 

 the others, and now appearing at the surface in detached areas. 

 All these ridges slope to the westward at an average angle of 

 10 — 15 degrees, and present bold mural faces to the eastward, 

 showing that they are outcropping edges of trap-sheets, that have 

 been left in relief by the removal of the softer sedimentary beds 

 that once inclosed them. 



QUATERIfARY PERIOD. 



There are no records in the rocks of Hudson County, belong- 

 ing to the Cretaceous or Tertiary ages, which followed the Tri- 

 assic ; during that immense lapse of time, this region must have 

 stood above the sea, and been clothed with the varied and 

 beautiful floras that have now passed away, and inhabited by the 

 strange reptiles of the Cretaceous and by many of the various 

 animals that roamed over our country in the mild and beautiful 

 Tertiary age. During the latter period, a climate as genial as 

 that of Virginia extended nearly if not fully to the pole, and 

 clothed the northern hemisphere with magnificent forests of tem- 

 perate and sub-tropical growths. In the succeeding period, all 

 this summer beauty was blotted out, and an age of ice succeeded, 

 when the present climate of high latitudes, with immense snow- 

 fields and glaciers, spread southward, until all the region from 

 Central New Jersey northward was buried beneath a vast 7ner cle 

 glace. The records of this glacial age occur abundantly in 

 Hudson County, and form one of the most marked chapters in 

 its history. 



The Drift. — Whenever the superficial material is removed 

 from above the trap-rock in Hudson County, we invariably find 

 the surface of the hard crystalline rock smoothed and polished, 

 and all the projecting ledges worn and rounded off. This 

 smoothed surface is also scratched and grooved in parallel lines 

 bearing usually N. 10° — 15° W. Upon this polished and striated 

 surface rests an irregular, confused accumulation of earth and 

 stones, from ten to twenty-five feet or more in thickness. This 



