63 



nated. Clouded, veined, and spotted, by various mineral naatters 

 mingled through it, and frequently susceptible of an excellent 

 polish, it promises to furnish, if attainable in masses of sufficient 

 size, a material of superior beauty for ornamental purposes in archi- 

 tecture. Various foreign minerals blend themselves occasionally 

 through the substance of the calcareous rock in every possible 

 proportion, from a few sparse crystals to such an abundance as 

 almost to replace the calcareous matter, which then merely fulfils 

 the part of a cement. 



These minerals, several of which are rare in the cabinets of 

 the mineralogist, constitute a list, when all are enumerated, of con- 

 siderable extent. Those which chiefly predominate, and which 

 tend by their prevalence to impart a certain uniform mineral 

 character to the altered limestone, are: Condrodite, or Bruc'ite, 

 in orange-yellow crj^stals; migite, common and crystallized; 

 plumbago, foliated usuall}'- in six-sided scales ; spinelle, often in 

 octohedral crystals : sahlite, and mica. 



The following catalogue, by Dr. Fowler, of Franklin, who has 

 zealously contributed to draw the attention of mineralogists to this 

 interesting region, exhibits a sufficiently detailed list of the mi- 

 nerals hitherto discovered in association with the altered lime- 

 stone : 



^^ Franklinite. — A new metalliferous combination, containing, 

 according to Berthier, of oxide of zinc 17, of iron 66, and man- 

 ganese 16 parts, is very abundant, indeed it appears inexhaustible. 

 It commences about half a mile northeast of Franklin Furnace, and 

 extends two miles southwest of Sparta, a distance of nine miles. 

 It is accompanied in this whole distance by the red oxide of zinc, 

 mutually enveloping each other. The greatest quantity appears 

 to be at Franklin Furnace. The bed here is about one hundred 

 feet high above the adjoining land, on the west side of it, and 

 from ten to forty feet wide. Various attempts have been made 

 to work this ore in a blast furnace, but without success. It fre- 

 quently congeals in the hearth before time is allowed to get it out 

 in a liquid state, in consequence of a combination of the iron with 

 manganese. All this difficulty, I apprehend, might be overcome, 

 if a method could be discovered of smelting iron ore in a blast 



