glinton's introductory discourse. 51 



Volney, borrowing the ideas of Mitchill without acknowledging the 

 obligation, has applied this theory to the United States at large ; and his 

 geological division consists of 



The granite region, 



The region of sand stone, 



The calcarious region, 



The region of sea sand, and 



The region of river alluvions. 

 He has, in one instance, departed from Dr. Mitchill's arrangement by 

 substituting a region of sea sand for a schistic region.* 



These are the principal attempts which have been made to illustrate 

 our geology, and although entitled to merit, they are imperfect, and, pro- 

 bably, to a considerable extent fanciful. Amid the thirty-eight different 

 substances which Maclure has mentioned as composing the different for- 

 mations, the others have designated but five ; and although I presume 

 that the denomination given to a particular region is only intended to 

 indicate that the principal rocks or substances are of the kind from 

 which the appellation is derived, yet it must be obvious, that in 

 such an extent of country it is utterly impossible to arrive at such a 

 conclusion without the most minute and scrutinizing surveys. It is diffi- 

 cult to distinguish and ascertain the different kinds of formations; it 

 requires considerable practical knowledge to discriminate between mat- 

 ter purely inorganic, and its mixture with organic substances ; and as 

 strata of different as well as of cognate species are not only piled upon 

 each other, but are frequently buried in the bowels of the earth, there 

 is great difficulty in forming just conclusions. This science, and the 



* See the Transactions of the American Philosophical Society, vol. 6. — Transactions of the 

 : ociety of Arts held at Albany, vol. J. ; and Volney 's View of the United States. 



