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distinct series of phenomena, corresponding to 

 these periods, each marked with its own peculiar 

 character. In referring to the first of these pe- 

 riods, if we examine the order and stratification 

 of the rocks we shall find various epochs, marked 

 with a sufficient degree of precision, during which 

 changes of the most extensive and important kind 

 have taken place, and fresh deposits have been 

 made, which have changed the aspect, and new 

 modelled the face of the earth. We can even as- 

 sign an order of time, as well as of other relations 

 to these changes. First, in this order, we find 

 granite, and other associated rocks, which have 

 justly been called primitive, because, while they 

 very often do rise above all others, they are seen 

 with surprising uniformity to dip below them all, 

 thus forming the solid foundation on which rests 

 the whole matter constituting the crust of the 

 globe. Next to these is discovered a series of 

 rocks which has been named the transition depo- 

 sit ; because, while rocks of this class certainly 

 rest immediately on the primitive, they have been 

 supposed to form an intermediate step between 

 this and what has acquired the distinctive appel- 

 lation of the secondary formation. Next to the 

 secondary succeeds the tertiary formation, which 

 constitutes the newest of the deposits belonging 

 to the first period of the world, and may be re- 

 ferred to the time immediately preceding the 

 Mosaic creation. 



This tertiary epoch must have ended in a vio- 

 lent catastrophe, occasioning an entire disrup- 



