Geology of Sexeca County. 113 



tion, the product seemed to be what it was claimed to be, very 

 tough and suited to cover culverts in roads. 



A series of 14 or more quarries extend along the east shore 

 of Covert for nearly six miles, at the distance of half or 

 three quarters of a mile from the lake, and probably 400 feet 

 above it, which would be 250 feet above the base, if 150 is 

 allowed for the Genesee shale. This, with the neighboring 

 quarries at Trumansburg and Taughannock, forms the district 

 of typical development of the industry. At present only one 

 quarry is worked at this point in Covert, and another is expected 

 to open next season. Those at Taughannock, with some advan- 

 tages of position, are working. ' 



The quality of the stone varies and much poor material has 

 formerly been disposed of at cheap rates. Some layers, appar- 

 ently solid, go to pieces under the hammer. IScaling sidewalks 

 and splitting wall stones may be seen. But when well chosen 

 the flags retain their position among the very best materials for 

 walks. The stone is of a very high degree of tenacity and dura- 

 bility, and does not become slippery by wear. Sills and cap- 

 stones are also made of it. It is found of 'sufficient thickness 

 for basement story work with rough face, for which it is now 

 being used at Willard's Hospital, and makes a handsome wall. 



Quarrying is facilitated in the Covert district by the compara- 

 tive lightness (1-8 feet) of the drift layer. In the more elevated 

 and central parts the drift is much heavier and has proved a 

 barrier to operations. The largest quarr}^ in the district is the 

 Ogden. There are also §ome large quarries near O dd Centre. 



Cleaved surfaces are slightly uneven ; sawing, for the produc- 

 tion of smooth surfaces, has not been put in practice to my 

 knowledge in this county. 



The accompanying view gives the quarry of King & Robinson, 

 who state the following in regard to it : The flags range in thick- 

 ness from two feet two inches down to " nothing." The thick layers 

 are liable to split ; in order to anticipate this they are artificially 

 separated by wedges into convenient thicknesses for slabs. The 

 thickest layer that can be relied on not to separate spontaneously 

 is eight inches through. Most of the good flags are furnished 

 by one 20-inch layer; at its greatest thickness this measures 22 

 inches and runs 40 rods each way (N. and S.), gradually thinning 

 15 



