100 Report on Building Stone of New York. 



were wanted. In working the quarry, holes of elliptical shape, and 

 four feet deep are put down with a reamer, aud then the blocks are 

 split along the line of these holes. The horizontal lifts are made by 

 wedges. The dressing of the large blocks is done on the stone dress- 

 ing floor at the quarry. A narrow-gauge railway runs through the 

 quarries, with switches to the several parts of the face, and terminates 

 at the canal, a half a mile away. Blocks of 130 cubic feet are con- 

 veniently gotten out and shipped. Two stationary engines work the 

 twelve derricks, and a portable boiler runs the steam drills. The 

 stone is of a light-blue color, dense and fine-grained. It is said to 

 weigh 175 pounds per cubic foot. Some of it has a slight ribbon- 

 like appearance, due to the lamination of the beds. The strength of 

 this stone is shown by the report of Prof. Thurston.* The greater 

 part of the stone is shipped over the line of the canal. The railroad 

 carries a small part only, and is over one mile distant. As the quarry 

 is above the natural drainage, there is no pumping. The natural 

 joints, which divide the rock into large, rectangular blocks, make 

 this location a favorable one for quarrying, and the stone is specially 

 adapted to heavy masonry ; very little of it is used for common walls 

 and house work. It is being used in the Arthur-Kill bridge on 

 Staten Island Sound, in the bridge piers at Poughkeepsie ; and for 

 the base of the Bennington Monument in Vermont ; also for the 

 Croton Acqueduct Gate House, New York. A large force of men 

 is employed the greater part of the year, and the output of the 

 quarry (in cubic yards), probably exceeds that of any other in the 

 State. 



These quarries are in the horizon of the Calciferous sand-rock, and 

 the stone is a siliceo-magnesian limestone. 



Half a mile north-east of the quarry of the Sandy Hill Company, 

 limestone has been opened in a low ledge, for a length of 150 yards, 

 north-east to south-west, and for a breadth of 30 yards. The quarry 

 face is 10 to 20 feet high, and the covering of earth is from one to 

 three feet. The dip of the bed is 8° south-east. One system of 

 seams or joints runs east and west and vertical : a second one at 

 right angles to the first ; and another, not so plain, runs south-west. 

 The beds are from one to four feet thick. The stone is hard and 

 brittle, but dresses readily, and the division of the mass of rock by 



* According to the published report of Prof. Thurston, the crushing- strength of 

 this stone, as shown by his tests, ranges from 18,500 to 28,500 pounds per square 

 inch. 



