INORGANIC GEOLOGICAL DYNAMICS. 601 



History of the Natural Changes of the Earth's 

 Surface which are proved by Tradition, the first 

 part, treating of aqueous changes, appeared in 1 822. 

 This work was occasioned by a Prize Question of 

 the Royal Society of Gottingen, promulgated in 

 1818 ; in which these changes were proposed as 

 the subject of inquiry, with a special reference to 

 geology. Although Von Hoff does not attempt to 

 establish any general inductions upon the facts 

 which his book contains, the collection of such a 

 body of facts gave almost a new aspect to the sub- 

 ject, by showing that changes in the relative extent 

 of land and water were going on at every time, and 

 almost at every place ; and that mutability and 

 fluctuation in the form of the solid parts of the 

 earth, which had been supposed by most persons to 

 be a rare exception to the common course of events, 

 was, in fact, the universal rule. But it was Mr. 

 Lyell's Principles of Geology, being an attempt to 

 explain the former Changes of the Earth's Surface 

 by the Causes now in action, (of which the first 

 volume was published in 1830,) which disclosed the 

 full effect of such researches on geology ; and which 

 attempted to present such assemblages of special 

 facts, as examples of general laws. Thus this work 

 may, as we have said, be looked upon as the begin- 

 ning of Geological Dynamics, at least among us. 

 Such generalizations and applications as it contains 

 give the most lively interest to a thousand observa- 

 vations respecting rivers and floods, mountains and 



