Kies — Physical Tests of Devonian Shales. 



691 



Buffalo. As a rule they are extremely impure and at times even marly. 

 They are soft shales, which weather very easily, and are generally red or 

 green in color and contain the beds of gypsum and salt. 



The Salina shales are well exposed at Warners, near Syracuse, where 

 they are utilized for making brick. 



Professor Hall says of the Salina or salt group (Geology of the Fourth 

 District of New York, p. 117), that it forms an immense development of shaly 

 marls and limestones, with interbedded deposits of gypsum. The formation 

 extends from Syracuse westward through southern Wayne county, and 

 northern Ontario and Seneca counties, northern Genesee and Erie counties 

 and a small part of the southern portion of Niagara. This group contains 

 important shale beds, although they are unfortunately very calcareous at 

 times and consequently require careful manipulation. 



The red shale forming the lower divisions of the group was not observed 

 west of the Genesee river. It appears in eastern Wayne county, as indicated 

 by the deep red color of the soil overlying it. At Lockville the greenish blue 

 marl with bands of red lias been quarried from the bed of the canal. West 

 of the Genesee this is the lowest visible mass ; the red shale has either 

 thinned out or lost its color, becoming gradually a bluish-green ; while other- 

 wise the lithologic character remains the same. On first exposure it is 

 compact and brittle, presenting an earthy fracture, but a few days are 

 sufficient to commence the work of destruction, which goes on till the whole 

 is resolved into a clayey mass. 



The green marl of the lower division appears near the canal at Fairport 

 and again at Cartersville. The bed of the stream at Churchville shows the 

 greenish-blue marl. 



"The prevailing features of the second division of this group," says 

 Professor Hall, " are a green and ashen marl, with seams of fibrous gypsum 

 and red or transparent selenite. It occurs in the vicinity of Lyons and 

 numerous points farther west/ 1 



The third division contains large gypsum beds and is probably not 

 suitable for use. 



The Salina shale, as stated above, is worked at Warners,. Onondaga 

 county, by the Onondaga Vitrified Brick Company. 



The shale as exposed in their bank consists of a green or red, soft, 

 argillaceous shale, of considerable impurity as the following analyses 

 furnished by the company show. 



