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chain, should have been acquired at the lime of the elevation of 

 the tertiary, or at any period later than that of the final drainage 

 of the middle secondary trough. The disturbances of level which 

 took place at the close of the newer secondary or greensand period 

 are still further in favour of the same conclusion ; for, while the 

 strata of that date were raised to a moderate height, averaging 

 sixty or eighty feet above the ocean in the latitude of New 

 Jersey, they underwent no permanent elevation above the tide 

 in the region further to the southwest, between the Chesapeake 

 and the Roanoke. 



That the almost universal inclination of the planes of depo- 

 sition in the red shale and sandstone formation is the result of 

 the oblique or slanting mode in which the sediment has been 

 laid down by a rapid and steady current, and is not due to any 

 upheaving action, admits, I conceive, of very little doubt. If it 

 were a consequence of the latter cause, the vast width of the 

 region in New Jersey over which this northwest dip prevails 

 would imply a thickness for the deposit so enormous as to be 

 beyond all precedent among stratified formations. But we have 

 conclusive evidence of the comparative shallowness of this group 

 of beds, in the fact, that, in several localities, even in the interior 

 of the belt, it has been washed off in patches by denudation, so 

 as to expose the subjacent Appalachian limestone, which appears 

 in these places to have been the original floor of the basin. The 

 denudation along the southeastern border of the tract has, in like 

 manner, in many neighbourhoods, cut away the coarse sandstone 

 and conglomerate beds — the first deposited, and undermost, by 

 order of dip — making the now undermost layers to consist of the 

 red shales. This could obviously not occur if the materials had 

 been precipitated in a nearly level position, as in that case they 

 would have spread themselves along the bottom of the trough too 

 far to the northwest to be removed by local denudation along its 

 southeastern margin. 



The very general dip of the strata towards the northwest and 

 north seems plainly to imply the side from which the sedimentary 

 matter chiefly entered this valley. That the lateral influx was 

 principally from the belt of country immediately bordering the 

 basin upon the southeast there can be little doubt; and we have 

 only to observe the nature of the rocks skirting that side of the 



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