92 



the present Paper, the author, after having made himself acquainted 

 by personal observation with the rocks of England, — states his opi- 

 nion, that the rocks in North America, which would appear from Mr. 

 Eaton's Synopsis to succeed one another in an order perfectly irre- 

 concileable with that which has been observed in the British Islands, 

 do in reality follow the same order. 



A comparative view of the respective systems, of Mr. Eaton and 

 the author of this letter, will be conveyed in the following table : — 



Series of North American Rocks. 



(According to Mr. Eaton.) (Mr. Featherstonehaugh.) 



Superficial Analluvion. 

 Stratified Analluvion. 

 Post Diluvion. 



Ante Diluvion Diluvium ? ? 



Basalt Basalt. 



3rd Grau- f Pyritiferous Grit ") ^ , ,. ,„ . . 



waeke. { Pyritiferous Slate / : ■ Coal measures of En S land " 



Cornitiferous Lime Roclo 



Geodiferous Lime Rock > Carboniferous Limestone. 



, . f Calcareous Grit J 



1 Calcareous Slate I T T - . C) , 



t, -r d , > Lower Limestone Shale. 



t ernlerous Rock J 



Saliferous Rock ") f Old red-stone, similar to that of 



Millstone Grit J " I Monmouth. 



2nd Grauwacke Grauwacke Slate. 



Metalliferous Lime Rock. . -) i Transition Limestone ; with En- 



Calciferous Sand Rock .. >.... < crinites,Madrepores,Corals,Tri- 



Sparry Lime Rock J f lobites, Products, Spirifera, &c. 



1st Grauwacke Whetstone-Slate, and Alum-Slate. 



Argillite Clay-Slate, and Flinty Slate. 



Granular Lime Rock Primitive Limestone. 



Granular Quartz. 



Talcose Slate Talcose Slate. 



Hornblende Rock. 



Mica Slate Mica Slate. 



Granite Granite. 



It is stated, moreover, to be the opinion of Mr. Eaton, that the 



coal measures of North America are analogous to those found at 



Cloughton on the Coast of Yorkshire ; and consequently that the 



English oolite, in which that coal is included, is represented by what 



he calls the third Grauwacke. The author dissents altogether from 



this doctrine. His opinion is, that neither the oolite, nor indeed any 



of the beds which are in England higher in the series than the coal 



measures, are to be found in North America, at least, north of 



40° north latitude ; unless, perhaps, a very thick and extensive bed 



of marl, destitute of fossils, but containing Septaria, and not unfre- 



quently pebbles, (designated by Mr. Eaton by the term antediluvion) j 



— which, though the author has not been able as yet to refer them to 



any of the regular formations, may hereafter be found to belong 1o 



some stratum in the English Series. 



