214 DISTRIBUTION OF SOILS. 



In tlic middle and western counties of New-York, where the outcrop of the rocks is north, 

 and where the line of strike is nearly east and west, the soil of each rock is carried south 

 upon the next one above, or perhaps beyond it. Here then the character of the soil of a 

 belt running east and west, is modified by intermixture with that derived from a rock at a 

 distance. For illustration, we may cite the soil of the Medina sandstone, which, cropping 

 out on the south shore of Lake Ontario, its debris is found overlying the next group of 

 rocks south of it ; and a similar change has taken place with the soil of the Onondaga-salt 

 group, which is carried up to the Onondaga limestone, and even still farther south, and it 

 thus modifies the soil embraced in a belt twenty-five or thirty miles soutii. To this fact, 

 the lands south are greatly indebted for their excellent properties in bearing wheat ; but 

 we shall have occasion to speak more particularly of this hereafter. 



If the strike of the rocks of Western New-York was parallel to the Taconic range, the 

 distribution of the soil would have altered materially the character of the belt of country 

 at the base of the Allegany ridge. Notwithstanding the transjxirt of the soil, it is not diflSi- 

 cult to find large areas with soil composed of the debris of the rocks beneath : it results 

 from the rapid decomposition of the rocks, or the ease with which air and water convert 

 them into pulverulent matter. This too has favored the production of a great depth of 

 soil ; and hence we find in Livingston county, and in the tier of counties in the same east 

 and west range, an immense depth of soil. In the Taconic range, although slates form a 

 large proportion of the strata, yet in consetjuence of the strike, and the angle at which they 

 are inclined to the horizon, far less debris has been formed than in Central New-York. 

 The strike is nearly in the direction of the drift current ; and hence the effect was far less 

 than it would have been if the loose materials had been driven directly against the out- 

 cropping edges of the inferior rocks, as in the case just noticed. This is strikingly mani- 

 fested in some parts of the Helderberg range, where the current encountered the outcrop- 

 ping edges of the thin-bedded sandstone of the upper Silurian beds, and not only broke 

 them up, but transported immense quantities far towards the base of the Catskill mountains, 

 where it lies in sucli profusion as to cover extensive areas with broken rocks, and (luis to 

 render large tracts of land nearly worthless. One of the rocks that is very abundantly 

 strewed over the fields of Greene county, is the Oriskany sandstone, which, in consequence 

 of its hardness, was able to resist attrition. The drifted soil of this region is frequently 

 one or two hundred feet deep, and it appears in many places to have been derived from 

 the outcropj)ing edges of the rocks of Albany count)^ 



§ 3. Causes of diluvial action. 



We now proceed to inquire into the causes or agencies concerned in the breaking up of 

 rocks, and in the transportation of the debris which covered them at the time these agen- 

 cies or powers were called into operation. We embrace these two plienomena in tlie single 

 question concerning the transportation of soils ; and in framing a hypothesis adequate to 

 the solution of this question, it is essential that every assumption should bear with equal 



