270 Dr. Fitton's ^0/^5 on the History of English Geology. 



* and as the mountai7ious countries are generally formed out 

 ' of the lower strata, so the more level countries are geiierally 

 ^formed out of the upper strata of the earth. 



' Hence it comes to pass that, in coiintries of this kind, the 



* same strata are found to extend themselves a great ivay, as 

 ' ivell in breadth as in length. We have an instance of this in 

 ' the chalky and flinty countries of England and France, which 

 ' (excepting the interruption of the Channel, and the clays, 

 ' sands, &c. of a few counties,) compose a tract of about three 

 ' hundred miles each way.' 



The account of the districts in America, above referred to, 

 has been confirmed, we believe, in general, by more recent ob- 

 servations : and nothing can be more clear than Mr.Michell's 

 exposition of the principle of the stratification of England. 

 That he was acquainted with the detail also, is proved by a 

 memorandum discovered in ]810, among the papers of Mr. 

 Smeaton, then in the hands of Sir Joseph Banks ; in which 

 are enumerated several of the principal beds, from the chalk 

 down to the coal ; detached portions, several miles distant from 

 each other, being, in two instances, associated under the same 

 name. — This paper is as follows * : 



Mr. Michell's Account of the South 

 of England Strata. 



' Chalk. 

 Golt, . 



Yards lif Thickness. 



120 

 50 



10 to 20 



' Sand of Bedfordshire 



' Northamptonshire lime, and ) 



Portland lime — lying in > 100 



several strata ) 



• Lyas strata 70 to 100 



• Sand of Newark about 30 



' Red clay of Tuxford, and \ ,qq 



several J 



• Sherwood Forest, pebbles and j ^^ ^^ .^ 



gravel ) ^ 



• Very fine white sand uncertain 



' Roche Abbey and Brotherton limes. 100 

 ' Coal strata of Yorkshire.' 



Present Names. 



Chalk. 



Gault. 

 I Wobiirn Sands, — 

 ( [Lower Green-sand.] 



( Portland and other 

 I Oolites. 



Lias. 



? 



New-red-sand. stone. 



{ Probably superficial 

 I Gravel. 

 ? 



( [Magnesian Lime- 

 \ stone.] 

 Coal-measures ? 



It is extraordinary that the very remarkable paper in the 

 Philosophical Transactions from which the foregoing extracts 



* We are indebted to the late Mr. Farey for the publication of this 

 valuable document, in the Philosophical Magazine, vol. xxxvi. p. 102, &c.; 

 and the list of modern names above given has been adopted from him. 

 The IhicJcness of most of the strata, he justly observes, is greatly underrated. 

 — The list was found, in Mr. Smeaton's writing, on a part of the back of a 

 letter bearing the London post-mark of November 21, 1788. Smeaton 

 himself died in September 1792. 



