CHANGE OF THE SEASHORES. 295 



the same species to dwell, at the same time, on any 

 part of the earth. The currents of the atmosphere 

 and the ocean were more and more decidedly and 

 definitively established. 



The extent of dry land was continually increased 

 by fresh elevations above the waters. Kivers and 

 lakes were formed ; in addition to the hitherto ex- 

 clusively marine deposits were those of the fresh 

 waters and salt pools. Plants growinj^ in marshes 

 or on dry lands extended their species over new con- 

 tinents. 



As time went on, the inequality of temperature at 

 different points of the globe augmented ; the existing 

 mountains increased in height; new ones were heaved 

 up ; the fauna and the flora became more localised, 

 and the marine and atmospheric currents approached 

 insensibly to the condition in \^hich we find them. 



2. The Shore — Its apparent fixity — Traces of the presence of the 

 Ocean almost universal. 



Have we yet reached fixed conditions, so far as 

 regards the earth's surface ? Can we be certain that 

 some fresh revolution of the globe will not destroy 

 the edifices of which we are so proud, and wrap in a 

 watery shroud the accumulated fruits of civilisation ? 

 If we have indulged in any illusion, it is only neces- 



