218 RELATIONS OF SOILS 



was faintly scored, ami the surface taken from it presented an exact cast in relief. But it 

 was particularly interesting i" discover, on the same day. the same stratum four miles 

 distant, in the same condition, only the stria and grooves were much deeper than those at 

 the Tillage of Plattsburgh. Of the extent of this smoothed surface, we have do means of 

 determining;. We had, however, observed the same thing a few years before, thirty miles 

 south of Plattsburgh. An interesting fact in this discovery, is, that the rock above is the 

 same as that below. There is no change in the lithological features of the rock : neither 

 is there any in the fossils. 



III. RELATIONS OF THE SOILS OF NEW- YORK TO THE ROCKS ON WHICH 



THEY REST. 



From what has been now said of drift and diluvial action, it may he inferred that the 

 soils are so far removed from their parent rock, that the one upon which they now repose 

 can not give us much light or information of their nature or composition. This is true to 

 a certain extent ; yet it is not so generally true in New-York, as in the New-England 

 States. Here, as every attentive observer must see, is a series of rocks, in the midst of 

 which there are many thick and heavy beds of slate and shale, and of slaty and shaly lime- 

 stone, which are eminently disposed to undergo disintegration. Now we have no doubt of 

 the statement we have already made in regard to the denudation of large areas ; still, such 

 is their inability to resist the changes of the climate, that in a few years the exposed and 

 naked surface would be covered again with soil. In all the great divisions of the New- 

 York system, decomposable beds occupy no inconsiderable portion of its surface. Observa- 

 tion fully sustains this view. A careful examination of the soil of the Onondaga-salt group 

 shows that it is derived from the rocks beneath : it is filled with small angular fragments, 

 where it is ploughed ; and these may be observed in all stages of decay, from lumps of the 

 size of a walnut, to a fine pulverulent soil. The same is true of the l~tica slate and the 

 slates of the Trenton limestone, and of the Marcellus shales and the Niagara green slate 

 or shale. Hence, though a most thorough removal of the whole soil of the early periods 

 may have taken place, yet the rocks of this State are such that they would soon be covered 

 again by their own debris ; but we by no means suppose that this remark applies to every 

 part of the Un'on, or even to all parts of this State indiscriminately. 



But we do not wish to be misunderstood in these remarks. It is true, that for large 

 areas, the soil is derived directly from the rock upon which it rests ; still it is not identical 

 in composition with the rock. The ro.ks, when pulverized, give quite a different analysis 

 from that which results from the soil. This is an important fact, and could not have been 

 known except by analysis and by experiment, though such a result is in accordance with 



