102 NEW yore: state museum 



There is a bed of clay at Dunkirk having a depth of over 20 

 feet. The upper six feet are yellow and of a sandy nature, while 

 the lower two thirds is blue and of much better quality. It is 

 mentioned by Prof. Hall* in his report, and is an instructive 

 example of the manner in which the clay changes in color, down- 

 ward as far as the water can percolate and oxydize the iron. 



Around Buffalo is an extensive series of flats underlain by a 

 red clay. A thin layer of sand suitable for tempering overlies 

 the clay in spots, and limestone pebbles are scattered through it. 

 Similar deposits occur at several localities to the north of the 

 ridge road and around Niagara Falls, also at Tonawanda and 

 La Salle, to the north of Buffalo, as well as south of it along the 

 shore of Lake Erie. Ko doubt much of this clay was deposited 

 during the former extension of the Great Lakes. 



Prof. Hall mentions deposits of clay at the following localities : 

 at Linden one mile south of Yates Center ; f along the shore of 

 Lake Ontario east of Lewiston ; on Cashaqua Creek :{: deposits of 

 tenacious clay due to the crumbling of the argillaceous green 

 shales; in Niagara County § beds of clay are said to occur in 

 every town, but they often contain a considerable amount of 

 lime. 



A bed of blue and red clay is being worked at Brighton near 

 Rochester. This deposit lies near the head of Irondequoit bay 

 and was deposited by some stream flowing into it. To the south- 

 east of Rochester is a large esker which extends in a northeast 

 direction to near Brighton. Mr. Upham, who has described this 

 esker, considers that it was formed by a river which flowed 

 between walls of ice and deposited the bed of clay above men- 

 tioned. II 



Clays are also found at several points in the valley of the 

 Oswego River from Syracuse to Oswego, an important one being 

 at Three Rivers. 



An extensive bed of red and gray clay, 20 acres in extent and 

 horizontally stratified, occurs at Watertbwn. The deposit is 20 

 feet thick and rests on Trenton limestone. 



* Geology of New York, 4th District, 1843, p. 362. 



t Ibid. p. 227. 



tibid. p. 437. 



§.Ibid, p. 444. 



i Proc. Amer. Asso. Adv. Sci., vol. XLI. 



