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Scientific Geology. 



find them abounding with the peculiar quartz bowlders that have 

 been described, just as would be the case if these had been driven up 

 said valleys by water after their excavation. Had the bowlders been 

 spread over the surface before the existence of the valleys, why should 

 they be so much more numerous in those valleys, than upon the hills ? 

 Alluvial agents would, indeed, tend to accumulate them in valleys; 

 yet by no means to the extent to which we now find them, especially 

 in broad valleys. 



Upon the whole, I have no hypothesis on this subject to propose, 

 more free from difficulties, than that which imputes the removal of 

 these quartz and gray wacke bowlders, in a southeasterly direction, 

 to the same debacle of waters, which, in other parts of the state, has 

 swept the detritus southerly. What local cause should have deflected 

 the current towards the east, in the western part of the State, and in 

 the eastern part of New York, I can hardly conceive : though, as I 

 shall shortly endeavor to show, there was considerable irregularity 

 in its direction in that region ; enough, perhaps, to lead to the suspi- 

 cion, that the deep valleys and ravines, through which the waters 

 must have rushed, might have considerably modified their course. 

 But I think that the change of a few degrees in the direction of the 

 current, is not so great an objection to this hypothesis, as the Sisy- 

 phean task, which must have been accomplished, if it be true, of urg- 

 ing upwards, over so long and steep inclined planes, bowlders so 

 large and so numerous. Making every allowance for the reduction 

 of the gravity of these bowlders when in water, I confess I cannot 

 conceive how such a work could have been effected by this agency. 

 Yet neither can I conceive how those diluvial elevations and depress- 

 ions, that have been described in various parts of the State, could have 

 been produced by a deluge. For they are on so large a scale, as to 

 transcend by far, the maximum effect, which I can conceive to be pro- 

 duced by a flood of waters. Still it is undeniable that these did re- 

 sult from such an agency. Hence I may underrate the power of that 

 same agency in the removal of detritus. 



I acknowledge, however, that I should be inclined to refer the dilu- 

 vial phenomena in the western part of the State, to a different and an 

 earlier deluge than the last — perhaps to the retiring waves when 

 the strata were first elevated — did not facts forbid it. I have men- 

 tioned some of these, and shall soon mention another still more con- 

 clusive. 



In stating the facts relating to the bowlders of sienite on Mount 



