xviii PREFACE TO THE FIFTH EDITION. 



it is undoubtedly a cataclysm ; if I tread on a beetle, 

 it is a catastrophe to the beetle ; but formation and 

 destruction are very different things, and the tenour of 

 my discourse applies to genesis, not extinction. Even 

 in phenomena such as those of Geology, though there 

 were doubtless cataclysms, and sometimes on a much 

 larger scale than at other times, yet the evidence seems 

 to me to point to their being limited in extent at any 

 one period, when compared with the whole terrestrial 

 surface. 



