^ i 



A 



J72 



ILLUSTRATIONS OF THE 



on, has been treated as abfurd by fome of 

 pponents, particularly Be Luc and Kirv 



Thefe philofopher 

 that their own fyfl: 

 which derive 



feem 



have obferved 



nil, and indeed every fyftem 

 the fecondary llrata from the 



primary, involves a tranfportation of material 



hardly lefs th 



IS 



fuppofed 



ory 



d a degradation of the 



Huttonian 

 primeval 



mountains, in many inftances much greater. 

 To form fome notion of this degradation, it muft 

 be recolled;ed, that 

 which furnifhed the ; 



ft 



in the 



the primeval mountains, 

 materials of the fecondary 

 cannot have flood in the 



now 



occupied by thefe pi 



Th 



IS IS 



ob 



d therefore we mull necefTarily 



gard the fecondary fl 



as derived from the 



primitive mountains which are th 



ra 



and of which a part ftill remains 



11 t( 



Thi 



s 



part is fufficient to define the bafe of the orig 



niountams : 



d th 



quantity of the fecondary 



flrata which furround them may help us to make 

 fome eftimate of their height. Let us take, for 

 inllance, the extenfive trad of fecondary country 



ab 



Newcaflle 



h 



coal 



m 



have been 



funk through a fucceffion of fecondary llrata 

 the depth of more than a thoufand feet. 



This 



fecondary country may be confidered as com- 

 prehending almoU the whole of the counties of 



ISlorthumberland and Durham, and probably as 



extending 



