396 
GEOLOGY OF THE FIRST DISTRICT. 
4. About three and a quarter miles northwest of Lower Redhook, on the road, on or near the 
land of Nathan Beckwith, is a ridge of black siliceous slate. Copper pyrites was 
rather abundantly disseminated in some of the loose masses of this slate. The same 
kind of black siliceous slate was seen in place on the next swell of land to the west. 
Several places where siliceous slate occurs, were seen between Lower Redhook and 
Clermont. 
5. “ Opposite to Troy, it is exhibited in a very perfect bed and below Troy, on the shore, 
beds of siliceous slate occur.* 
6. “ It forms most of the bank of the Hudson river at and below the city of Hudson, pass¬ 
ing into beautiful lydian stone in some places.”* 
7. The green jaspery slate is common, but not in large beds or masses so far as observed, 
except one, which is three or four miles south of Albany, described by Profs. Eaton 
and T. R. Beck, in the Geological and Agricultural Survey of Albany County. 
The flinty or siliceous slate assumes almost every variety of aspect, from common 
siliceous slate, through basanite or touchstone to hornstone and petrosilex. 
8. At Blue hill, about four miles south-southwest of Hudson. The slate varies from fissile 
to compact, and in some places is changed into basanite, petrosilex, and hard compact 
siliceous slate ; and in color, is black, blue, red and green. The strike of the rocks is 
somewhat variable, but is generally about S. 30° W. 
9. In Chatham, one and three-quarter miles from Malden, on the road to Valatie, a ridge of 
compact siliceous slate was seen in the meadow on the east side of the road. Red 
jaspery slate was seen abundantly in loose masses near the same place, but not in situ. 
10. In Chatham, above Rider’s mills, near the road to New-Lebanon, and near the north line 
of Columbia county, red jaspery slate was observed in place. Several localities of sili¬ 
ceous slate were observed along the Kinderhook creek, on its left bank, between 
Rider’s mills and Valatie. Siliceous slate and red jaspery slate were also seen in 
Granville, Washington county, between Granville and West-Poultney. 
Many more might be mentioned, but it is unnecessary to multiply localities. They are 
generally situated on or near the transverse axes of disturbance, and at or near the intersec-' 
tions of these northwest and southeast axes with the principal north-northeast and south-south¬ 
west axes of fracture and upheave. 
Eaton’s Geological and Agricultural Survey of the vicinity of the Erie Canal, p. 69. 
