6 NEW YORK STATE MUSEUM 



frequently seen in the glacial gravels, he makes the following 

 statement in regard to the faults here referred to : 



The other class is where the slate rocks on the east side of 

 the Hudson valley had been ground down, smoothed, deeply 

 grooved and scratched across their edges ; and since the action 

 that had produced these effects the masses of slate had been 

 shifted a few inches in a vertical direction by a slight fault, so 

 that the grooves and scratches on the lower part of the mass 

 were continued quite up to that part that had been elevated; 

 and on the upper mass, the same grooves that had been once con- 

 tinuous, were prolonged in their former direction, with the same 

 breadth and depth. This shift of position, or slight fault, must 

 have been subsequent to the period when the scratches were 

 made, or the scratches could not have been continued close up to 

 the vertical surface of the more elevated portion,- and without 

 wearing the sharp edge of the slate on the upper portion of the 

 shifted mass. This locality was where the Quaternary had 

 covered it, but the example can not with certainty be referred 

 to that part of the Quarternary period of which we are now 

 speaking; for it may belong to the elevation that took place 

 after the drift period, and preceding the elevation by which the 

 Quaternary deposits were raised to their present level. 



The locality and example referred to above, w r as observed by 

 myself in Copake or Ancram near the north end of Winchell's 

 mountain, and not far from the base of Mount Washington, on 

 the road from Copake to Boston Corners. 1 Professors Merrick 

 and Cassels were present with me, and I called their attention 

 to this, as an important fact for them to observe, in consequence 

 of the kind of evidence thus afforded of the relative periods of 

 time during which the rocks were disturbed in position. Pro- 

 fessor Merrick, a few days afterwards, in his explorations, dis- 

 covered several more localities near each other, about half a mile 

 west of Long Pond in Clinton, 2 where the same facts were 

 observed. I quote his report to me. 



An interesting phenomenon may be seen in the rocks about 

 y 2 mile west of Long Pond in Clinton. The parts of the rock 

 have changed their relative position since they were worn down 

 by the diluvial action. In two different places, at but a short 

 distance from each other, one part of the rock has been raised, 

 or the other part settled from 2 to 3 inches, the strata being 

 nearly vertical. Five or six similar dislocations, of from half an 

 inch to 1 inch, occur in the immediate vicinity. 



Of the dislocation of the rocks since the effects of the diluvial 

 action upon it, there can be no doubt, as the scratches or furrows 

 upon the elevated and depressed parts precisely correspond, and 

 are carried on the latter entirely up to the former, the elevated 

 ridge of which is unmarked or broken (unbroken?). These dis- 



*This is probably the locality described below on p. 16. J. B. W. 

 2 I have not yet seen this locality. /. B. W. 



