GRAPHITE OR PLUMBAGO. 97 



Texture sometimes foliated and sometimes granular, often also a little slaty. It has been 

 met with crystallized in six-sided prisms ; but nothing is known respecting the angles of these 

 crystals. 



Chemical nature. Graphite was for a long lime regarded as a carburet of iron ; but it is 

 now thought that the iron, which is very variable in quantity, and which indeed seldom exceeds 

 ten or eleven per cent., is entirely accidental. The graphite of Barreros in Brazil, leaves 

 scarcely a trace of residuum when it is burned ; and the graphite which forms in high fur- 

 naces is sometimes entirely free from iron. Native graphite, however, most generally contains 

 a proportion of this metal, together with variable quantities of earthy matters. This mineral 

 may be regarded as carbon, differing only from the diamond, charcoal, &c. in the mode of 

 aggregation of its ultimate particles. 



The localities of graphite in this State are very numerous, but the mineral is seldom found 

 in quantities sufficient for any useful purpose. The limestones of the counties of New-York, 

 Westchester, Rockland, Orange, Ulster, Clinton, Essex, Franklin, St. Lawrence 

 and Jefferson, abound with it, sometimes in the form of irregular folia;, and sometimes in 

 that of regular six-sided plates. 



Dutchess County. There are in this county some important localities of graphite. One 

 of these is on the farm of Mr. Peter Dewint, two and a half miles south of Fishkill Landing. 

 Several tons have been obtained here, and sent to market. It occurs in the granite, in a vein 

 several inches wide at the surface, and increasing gradually as it descends, to two or three 

 feet. About forty or fifty feet of this vein are exposed, and there appears to be every indica- 

 tion that there is an abiuidant supply of the mineral. The specimens which arc obtained at 

 this place are both foliated and granular, and are of sufficient purity for nearly all the pur- 

 poses to which graphite is applied. There is another vein of a similar kind, but less impor- 

 tant, at Fishkill Hooks. 



Essex County contains several good deposits of this mineral, especially in the vicinity of 

 Ticonderoga. One of these is about two and a half miles from the village at the Upper falls. 

 It is a vein of the purest foliated graphite, several inches in width. The folise often have a 

 radiated arrangement, and are of considerable size. The gangue is calcareous spar, which 

 sometimes exhibits large and perfect cleavages. Granular graphite is also found associated 

 with the above. 



This mine has not been much worked, but a considerable quantity of pure graphite is 

 annually obtained from it, which is sold for a shilling a pound. It is thought that this is an 

 extensive deposit. 



There are other veins of this mineral in the immediate vicinity, from which large and very 

 pure specimens have been obtained. At the Kirby mine, five miles northwest of the village 

 at the Upper falls, there is a vein of graphite of some width. The mineral is here cither 

 granular or in small folia^, associated with white quartz. 



Part I. 13 



