MINERAL RESOURCES OF THE STATE OF NEW YORK 245 



extensively in Rensselaer and Columbia counties. According to 

 Mather in his Report on the First District, " A range of roofing 

 slate extends from New Lebanon through Canaan, Austerlitz, 

 Hillsdale, Copake, Ancram and Pulver's Corners in Northeast. It 

 is believed to be the sam.e as that in which the Hoosick quarries are 

 located. Quarries of roof slate have been opened in this range of 

 rocks in many places. The most important are those in New 

 Lebanon, about i| miles from the springs on the east face of the 

 mountain." Near New Hamburg, Dutchess county, occur slate 

 beds that yielded mill stock and were worked as late as 1898. 



Quarry work. Open quarry excavation is the only method 

 pursued in the New York State region. The excavation follows the 

 seam or " vein " which usually has a steep dip and the quarries 

 soon become deep pits which require more or less constant pumping 

 to keep them dry. Considerable stripping is often necessary to 

 reach the valuable slate. The blocks as they are loosened by the 

 workmen, who avoid the use of powder as much as possible, are 

 hoisted by a derrick or in the large quarries by a stationary cable 

 with a traveler. Those unfit for use are dumped on the waste 

 piles which are conspicuous objects in the vicinity of all the larger 

 and older quarries. The good slate is loaded on cars or is carried 

 by the hoisting apparatus directly to the trimming sheds where the 

 blocks are split and squared into roofing slates. The mill stock, 

 which lacks the ready cleavage of roofing slate, is not finished at 

 the quarries but sent to mills for the purpose, where it is reduced 

 to shape by saws and planes. The cleaving of roofing slates requires 

 a degree of skill but is performed quickly by chisel and mallet. 



The wastage in quarry work is enormous, particularly with the 

 red slate, of which the valuable material may constitute only a 

 small fraction of the total quantity removed from the pits. In no 

 other branch of the quarry industry is so much dead work necessary, 

 or the issue of an enterprise surrounded by so much uncertainty. 

 Quarries that have been opened at considerable expense may have 

 to be abandoned before any appreciable return can be obtained, 

 owing to variations in the quality or to the loss of the seam which 

 could not be anticipated. The business, therefore, is a precarious 

 one. 



Until recently very little use was made of the waste from the 

 quarries. Some of the red slate is employed for grinding into paint 

 but the amount so used has had no appreciable effect upon the 

 accumulation of the waste. In the last year or two a demand has 

 developed for crushed slate in the preparation of composite roofing 



