v] OF EVOLUTION 37 



independently arrived at, were almost identical with 

 those of the great Scotch philosopher. But Scrope 

 made the same mistake as Huttou had done before 

 him. He allowed his theoretical conclusions to 

 precede, instead of following upon an account of 

 the observations on which they were based. Scrope's 

 book is certainly one of the most original and 

 suggestive contributions ever made to geological 

 science ; but the very speculative character of a 

 large portion of the work led to the neglect of the 

 really valuable hypotheses and acute observations 

 which it contained In the preface, however, the 

 author gives a most striking and complete summary 

 of the doctrine of Evolution as opposed to Cata- 

 strophism, in the inorganic world, as will be shown 

 by the following extracts : 



Geology has for its business a knowledge of the processes 

 which are in continual or occasional operation within the limits 

 of our planet, and the application of these laws to explain the 

 appearances discovered by our Geognostical researches, so as from 

 these materials to deduce conclusions as to the past history of 

 the globe. 



The surface of the globe exposes to the eye of the Geognost 

 abundant evidence of a variety of changes which appear to have 

 succeeded one another during an incalculable lapse of time. 



These changes are chiefly, 



I. Variations of level between different constituent parts of 

 the solid surface of the globe. 



