198 PLEASANT WAYS IN SCIENCE. 



earth's subterranean forces are still engaged upon. Even 

 now continents are being slowly depressed or upheaved, 

 even now mountain ranges are being raised to a different 

 level, table-lands are being formed, great valleys are being 

 gradually scooped out ; old shore-lines shift their place, old 

 soundings vary ; the sea advances in one place and retires 

 in another; on every side nature's plastic hand is still at 

 work, modelling and remodelling the earth, and making it 

 constantly a fit abode for those who dwell upon it." 



