Native Crystallized Carbonate of Magnesia. 145 



Siting the stalactical, cylindrical, and botryoidal forms, often 

 displaying a black polished surface and glistening lustre. 

 Ferruginous minerals are abundant on the mountain for seve- 

 ral miles. A granular oxide, called by miners shot-ore,* from 

 its being principally composed of spherical grains of various 

 sizes, was often noticed, and appears in some places in exten- 

 sive beds : it is easily fused, and affords a large per centage of 

 good iron for castings. A heavy ore, with a smooth surface 

 and some lustre, bearing a considerable resemblance to native 

 if on, is sometimes seen. Banks of white sand, resembling the 

 siliceous particles of the seashore, are noticed on the moun- 

 tain tops, containing masses of compact, heavy ferruginous 

 sandstone, similar to the rocks of our alluvial seaboard. Large 

 beds of water-worn siliceous pebbles, in no way differing from 

 those washed by the ocean, are seen on the height of the 

 ridge, in which excavations have been made several feet, 

 leaving the depth of the mass uncertain. On some of the 

 eminences, for a considerable extent, vegetation is entirely 

 excluded by an iron-bound soil. Iron ore, imbedded in an 

 earth coloured by, and partly composed of, oxide of iron, 

 occupies the surface ; and chalcedony and radiated quartz are 

 sometimes observed on the primitive ridge. Prospects from 

 many of these eminences are extensive and diversified. On 

 one side, the ocean and a great extent of coast are in view ; 

 on the other, a rich landscape of hills and plains, the eye rest- 

 ing on the highland-chain and the mountains bordering Penn- 

 sylvania ; the harbour, at your feet, presents a busy, ever- 

 varying scene, and the city of New- York appears to great 

 advantage from this point of observation. 



The district between the mountain and the narrows, the 

 thickly settled and well-cultivated plain bordering Amboy bay, 

 and much of the western division of the island, are decidedly 

 alluvial. Adjacent to Fort Tompkins, detached pieces of cop- 

 per ore have been found. I have observed petrifactions of 

 marine shells in rocks excavated in that neighbourhood, 

 twenty feet from the surface, and sixty gbove the ocean. 



* Doubtless the nea ore of (be Wprnerians. Editor 



