DESCRIPTIVE NOTES OF QUARRY DISTRICTS AND QUARRIES 24 1 



output in cubic yards is greater than that of any other 

 single building-stone quarry in the state, and is increasing 

 from year to year. 



The stone is of a light blue color, and fine-grained. Its 

 specific gravity is 2.764 and its weight per cubic foot 172 

 pounds. A partial chemical analysis gave 27.35 P^^ ^^^^^^ of 

 matter insoluble in dilute hydrochloric acid. The lime 

 and magnesia are present in proportions approximating to 

 a dolomite. The absorption capacity was found to be 0.14 

 per cent. When treated with a one per-cent solution of 

 sulphuric acid the loss in weight was 2.51 per-cent. Freez- 

 ing and thawing did not produce any apparent effect. 

 Exposed to a heat of 1200° to 1400° F. the stone was par- 

 tially calcined and crumbled with a blow. On account of 

 its hardness, it cannot be dressed economically, and very 

 little of it is used for house-work. It is specially adapted 

 to heavy masonry. It was used in the Arthur Kill bridge 

 on Staten Island Sound, in the rear wall on Governor's 

 Island, in the walls of the sunken track of the Harlem rail- 

 road, in the Croton aqueduct gate-house. New York city, in 

 the Poughkeepsie bridge piers, and in the battle monument 

 at Bennington, Vermont. 



Glens Falls. — There are two large quarries in the Tren- 

 ton limestone, one on each side of the Hudson river at 

 Glens Falls. That of the Morgan Lumber and Lime 

 Company on the Saratoga county side is no longer worked 

 for building stone. The quarry on the left bank, in Warren 

 county, belongs to the Glens Falls Company, and is worked 

 for black limestone or " marble." 



There is a long working-face in which a gray, crystalline 

 limestone is seen in thin beds at the top, then the black 

 marble, which has, in two beds, a total thickness of twelve feet. 



The gray limestone is sold in the rough for common 

 wall-work, or cut into house-trimmimg material. 



The black marble is fine-grained and compact, hard and 

 brittle, but can be dressed in any style. It takes a brilliant 

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