LAMARCK'S WORK IN GEOLOGY loi 



2. Why does the sea constantly occupy a basin 

 within the limits which contain it, and there separate 

 the dry parts of the surface of the globe always pro- 

 jecting above it ? 



3. Has the ocean basin always existed where we 

 actually see it, and if we find proofs of the sojourn 

 of the sea in places where it no longer remains, by 

 what cause was it found there, and why is it no longer 

 there ? 



4. What influence have living bodies exerted on 

 the substances found on the surface of the earth and 

 which compose the crust which invests it, and what 

 are the general results of this influence ? 



Lamarck then disclaims any intentions of framing 

 brilliant hypotheses based on supposititious princi- 

 ples, but nevertheless, as we shall see, he falls into this 

 same error, and like others of his period makes some 

 preposterous hypotheses, though these are far less so 

 than those of Cuvier's Discours. He distinguishes 

 between the action of rivers or of fresh-water cur- 

 rents, torrents, storms, the melting of snow, and the 

 work of the ocean. The rivers wear away and bear 

 materials from the highlands to the lowlands, so that 

 the plains are gradually elevated ; ravines form and 

 become immense valleys, and their sides form ele- 

 vated crests and pass into mountains ranges. 



He brings out and emphasizes the fact, now so 

 well known, that the erosive action of rain and rivers 

 has formed mountains of a certain class. 



" It is then evident to me, that every mountain 

 which is not the result of a volcanic irruption or of 

 some local catastrophe, has been carved out from a 

 plain, where its mass is gradually formed, and was a 



