Geology and Topogra^phy of Western Neio York. 93 



those portions which have been removed from the intermediate 

 valleys, could hardly have resulted from any sudden irruption of 

 water. The strata would have been indiscriminately torn up ; 

 and the ruins, instead of being finely pulverized, and beautifully 

 distributed over the surface, to hide the " nakedness of the land," 

 and prepare it for cultivation, would have been thrown together 

 by the eddies of the currents into unsightly heaps ; and this fair 

 region, instead of being the "garden of the West," would have 

 presented to view the uncouth surface of barren rocks, and would 

 have offered, comparatively, few inducements for the laborious 

 enterprise of the agriculturist. 



But to return.- — Suppose this dividing ridge to have attained 

 an elevation above tide water. The southern slope would pre- 

 sent to the waves the smooth surface of the strata ; whereas their 

 basseting edges would be exposed on the northern declivity. 

 Deep notches would soon be worn into it from both sides, which 

 would occasionally interlock, and sometimes meet ; thereby cut- 

 ting the ridge into a series of islands, with transverse passes be- 

 tween them. These islands now form the highest peaks of the 

 range; and the passes correspond to the elevated valleys, in 

 which the principal streams take their rise. 



When a considerable elevation had been attained, small stream- 

 lets would collect; and at the places where they entered the sea, 

 the waves and the tides would be more powerful in tearing up 

 and removing the shaly rocks, than at any other points ; and 

 thereby a system of valleys of denudation, precisely similar to 

 those we here witness, would be commenced. On the southern 

 slope, where the streams flowed over the inclined planes of the 

 strata, in the direction of their dip, they would meet few ob- 

 structions, and lakes would seldom be formed. Not so on the 

 northern declivity. There, where the streams flowed over the 

 edges of the strata in an opposite direction, each harder layer, 

 being longer able to resist the denuding process, would, for a cer- 

 tain distance, form the bed of the stream ; and the dip, being in 

 the direction opposite to the current, a succession of pools of 

 slack water would result. These phenomena may frequently be 

 illustrated by the small streams on the northern slope of a hill, 

 where some of the strata are composed of hard, close-grained 

 gray wacke ; while those on the southern declivity of the same 

 hill, present an opposite result. 



