210 new yoke: state museum 



In the southern portion- of the state we find clays in abundance, 

 in all the valleys, and lowlands. The extensive marshes near 

 Randolph and Conewango are said to be underlaid by clay 

 throughout their entire extent. 



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

 Rochester. This deposit lies near the head of Irondequoit bay. 



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. 



Deposits of clay suitable for brick and tile occur extensively 

 in the lowlands bordering the Mohawk river from Rome to Sche- 

 nectady. The beds vary in thicknesis from six 'to 15 feet and are 

 mostly of a red, blue or gray color. 



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

 horizontally stratified, occurs at Watertown. The deposit is 20 

 feet thick and rests on Trenton limestone. 



Another deposit of considerable size is being worked at Og- 

 densburg. The clay is blue and has a depth of 60 feet. 



HUDSON VALLEY 



Among the most extensive and important clay formations 

 occurring in New York are those of the Hudson valley. These 

 deposits indicate a period of depression, and deposition in quiet 

 water. The clay is chiefly blue, but where the overlying sand is 

 wanting or is of slight thickness, it is weathered to yellow, this 

 weathering of ten extending to a depth of 15 feet below the sur- 

 face, and to a still greater depth along the line of fissures. The 

 depth of oxidation is of course influenced by the nature of the 

 clay; the upper portion weathering easily en account of its more 

 sandy nature and hence looser texture. Horizontal stratification 

 is usually present, and the layers of clay are separated by ex- 

 tremely thin laminae of sand. At some localities the layers of the 

 clay are very thin and alternate with equally thin layers of sandy 

 clay. This condition is found at Haverstraw, Croton, Dutchess 

 Junction, Stony Point, Fishkill, Cornwall, New Windsor, Catskill 

 and Port Ewen. At all of the above-mentioned localities except 



