President of the Geological Society for 1850. 13 



of the Alps, and its great elevation, as " a clear demonstra- 

 tion of a sudden operation or catastrophe."* 



Now, I shall first venture to remark, in regard to these 

 theoretical views, that the Alps, when considered as a 

 mountain-chain which has originated entirely since the com- 

 mencement of the tertiary period, bear emphatic and irrefra- 

 gable testimony to the fact, that the intensity of the causes 

 which have disturbed the crust of the globe has not dimi- 

 nished in the tertiary as compared to the secondary or pri- 

 mary fossiliferous epochs. It may possibly be still contended, 

 that the energy and violence of the movements were more 

 general in those earlier epochs, supposed by some to have 

 been close upon the confines of '' the reign of Chaos and Old 

 Night ;" but it cannot be pretended that there are any proofs 

 of a more magnificent development of the disturbing forces 

 in any given region of equal extent, and accomplished in an 

 equal lapse of time, at any period antecedent to the upheaval 

 of the Alps. If, however, any one should maintain, that in 

 the earlier ages the movements which upheave, depress, and 

 derange the position of strata were more general, and that 

 they agitated simultaneously much wider horizontal areas, 

 it will be easy to adduce the most overpowering evidence to 

 the contrary. The wide extent in the United States of 

 America, and in parts of Russia, of Carboniferous, Devonian, 

 and Silurian strata, which, although upraised above the sea, 

 continue almost as level as when the beds were first thrown 

 down beneath its waters, clearly demonstrates the limitation 

 of the agency to which great foldings and contortions of 

 stratified rocks have been due to very confined spaces in 

 each epoch. Were it otherwise, the multiplication of such 

 extensive convulsions during a long succession of ages would 

 have made it impossible to find any spot on the globe where 

 the oldest rocks had escaped extreme derangement. It only 

 remains therefore for the advocates of the paroxysmal hypo- 

 thesis to assert that, although the disturbing forces have by 

 no means grown feebler in the modern or tertiary times, as 

 compared to periods when the oldest of the known strata 



* Quart. Journ. of Geol. Soc, vol. v. p. 258. 



