ee ae 
in the Counties of New-Haven-and Litchfield. 203 
dation at no great depth is rock, and the junction of primi- 
tive and secondary country evidently takes place in this val- 
ley. It has been supposed to contain coal, and I know of 
no geological fact which contradicts this opinion, and there 
are some in favor of it. 
Primitive Slate Rocks. 
5 
n 
— that the quartz has arisen from the decomposition of the shistose — 
rata, 
t Some researches for coal have been made in these slate rocks, but, it is . 
*xtremely evident that coal cannot be found in hills that are decidely prim- 
itive ; all such expectations concerning this region are less. 
