Introduction to Geology\ US 



mits of hills, and remain solitary remnants of strata once con- 

 tinuous, and interesting memorials of past revolutions. 



Among other proofs of the recurrence of such revolutions, 

 in an earlier state of the globe, maybe classed those breccious 

 rocks and conglomerates which are composed of the fragments 

 that originally occupied, or yet partially occupy, remote situ- 

 ations. The effects of a destructive power, as exhibited in the 

 abruption of escarpments and the excavation of defiles, are 

 also manifested by the reproduction of new rocks from the 

 debris ; and it has been further remarked, that these conglo- 

 merate rocks bear marks of a similar destructive agency, 

 occurring at some period subsequent to their consolidation. 



The tertiary formations also exhibit proofs of similar cata- 

 strophes, in the alternation of marine and fresh-water strata, 

 and in the mingled accumulations of animal and vegetable 

 remains derived both from the sea and the land. " Life, 

 therefore," observes M. Cuvier, " has been often disturbed on 

 this earth by terrible events : calamities which, at their com- 

 mencement, have, perhaps, moved and overturned, to a great 

 depth, the entire outer crust of the globe ; but which, since 

 these first commotions, have uniformly acted at a less depth, 

 and less generally. Numberless living beings have been the 

 victims of these catastrophes; some have been destroyed by 

 sudden inundations, others have been laid dry in consequence 

 of the bottom of the seas being instantaneously elevated. 

 Their races even have become extinct, and have left no me- 

 morial of them, except some small fragments which the natu- 

 ralist can scarcely recognise. Such are the conclusions which 

 necessarily result from the objects that we meet with at every 

 step of our enquiry, and which we can always verify from 

 examples drawn from almost every country. Every part of the 

 globe bears the impress of these great and terrible events so 

 distinctly, that they must be visible to all who are qualified to 

 read their history in the remains which they have left behind." 



JDiluvium, 



Over a large portion of the surface of our island, particu- 

 larly towards the south and east, is spread a covering com- 

 posed of the fragments of rocks, clay, sandstones, and chalk ; 

 which debris, or broken portions, were evidently brought 

 thither, and were irregularly accumulated, by means of pro- 

 digious currents which swept over the face of the earth. These 

 appearances are confirmatory of the Mosaic account of the 

 deluge, and by such an agency alone can these phenomena be 

 adequately accounted for. The catastrophe appears to have 



