44 A GEOLOGICAL HISTORY. 



a shale containing Bitumen, and many of the same 

 types, as are founed in the coal fields at Chester- 

 field, near Richmond in Virginia; where are also 

 the same impressions of fish, ferns, plants and 

 bitumen ; the specimens brought from thence by 

 Dr. Draper and presented to "the Lyceum of 

 Natural History" have the same fossils and same 

 character. At the new locality at Pompton, there 

 are according to Mr. Aaron It. Thompson's 

 account, three different series of rock, which lie 

 thus — first and lowest, lies the Sandstone, then 

 shale, with bitumen, impressions of fish, &c, then 

 on the top a conglomerate of pebbles with a 

 calcareous cement, this conglomerate is the same, 

 as what is called at Shawanjunk Mountains, 

 " iEsopus Millstone," and by Professor Rogers 

 " Potomac Marble," which is composed of quartz 

 pebbles and aluminous slate and in which not 

 unfrequently are seen small crystals of native alum 

 or a kind of Sulphate of Alumine. At and on the 

 road which runs from the " water gap," of the 

 Delaware River, this is again seen and is a COn- 



Stee plate 8, fig. 1. Which represents a section of the rocks with' the 

 fault, as seen on the east side of the Ramapo River, about-half a mile north 

 of Mr. Ryerson's Iron Works, in a ravine through which a brook runs- 

 Plate 8, fig. 2, represents the rocks on the opposite side of the ravine, 

 with a spur of trap at the highest point. 



