282 GEOLOGY OF THE SECOND DISTRICT. 



more like a stain than a fixed and incorporated color, penetrating and filling up all the 

 interstices. 



The glazed slate, beneath the sandstone, is not so clearly exposed as at Snake mountain, 

 yet it may be observed between the two eminences near the summit of the hill. The fracture 

 and uplift are equally distinct, but the elevation is not so great, neither was the force so con- 

 centrated as in the former instance : part of the effect seemed to have been spent in the dis- 

 turbance of the limestones at the base of the hill, bringing up and disrupting the chazy 

 limestone, and giving it a westerly dip. The phenomena in general are the same here as at 

 Addison, excepting that the rock is tliimier bedded, and more regular in the planes of depo- 

 sition. 



The sandstone at Charlotte is destitute of fossils : not even a vestige of one has ever been 

 discovered along the whole range from Columbia county to the Canada line ; and still it appears 

 to be a mass equivalent to the grey sandstone immediately below the Medina sandstone, which, 

 occasionally at least, contains fossils, though it must be confessed they are much less common 

 than in the shaly sandstones of Loraine. 



The materials of this rock appear to have been derived from the slates of the Taconic sys- 

 tem, which succeed on the east. The position of these rocks favors this view ; and besides, 

 when we examine the quartz in this sandstone, we find it possessing the same characters, par- 

 ticularly in its translucency. In addition to this, it has often the green chloritic coloring 

 matter of those slates, which is very distinct too in the coarser or brecciated varieties. 



One important and interesting question arises, when we have completed our examina- 

 tion of the masses which are exposed by the fractures and in the uplifts above described : Is 

 the whole and entire thickness of the Hudson river shales exposed ! Without answering 

 directly in the afiSrmative, I would say, that in and among these shales, I have not discovered 

 masses possessing other characters, or so materially distinct as to throw them out of the group. 

 In other words, I would say, that the different parts of the mass exposed in these uplifts 

 represent the whole mass of the Hudson river shales. Where they are undisturbed, their 

 thickness in the Second Geological District never exceeds five hundred feet. In this disturbed 

 range east of the Hudson river and Lake Champlain, I find about the same thickness. In 

 proof of this, I cite the thickness of the whole mass at Snake mountain and at Charlotte, 

 where, from the calciferous upward to the grey and reddish grits or sandstone, we pass over 

 the trenton, utica slate, and a mass of shales whose characters are those of the Hudson river ; 

 and as wc find the same rocks here with about the same aggregate thickness that we find them 

 in the undisturbed district in Jefferson county, I believe we may conclude that the affirmative 

 of the question proposed above is in part at least sustained. 



