THE MINING AND QUARRY INDUSTRY I9II 



17 



Production of common building brick 



(i Includes in 1910. Chemung, Clinton, Montgomery, Ontario, St Lawrence, Steuben, Tompkins, 

 Warren and Washington counties. In 191 1 the same counties are included excepting Steuben 

 which reported no production. 



Hudson river region. The greater part of the brick production 

 of the State is made in the Hudson river valley in the stretch 

 from Albany and Rensselaer counties southward to Rockland and 

 Westchester counties. The existence of extensive clay beds suit- 

 able for the common grades of brick, the facilities for cheap trans- 

 portation, and the proximity to the large market of New York City 

 and vicinity combine to make this section the largest brick-manu- 

 facturing district in the United States. 



The brick clays are found in terraced deposits on either side 

 of the river, extending from the water level to a height of 

 300 feet or more in places. They are interbedded with and some- 

 times covered by layers of sand and gravel. Their thickness at 

 any locality may exceed 100 feet, though usually it is much less. 

 Some clay has been obtained by dredging from the bed of the 



