550.1 117 



IV 



Suess's Theories of Geographical Evohition ^ 



IN spite of the apparent fickleness and inconstancy of the sea, tlie 

 idea recurs throughout poetic literature that its main character 

 is really its immutability. From Homer to Kipling, from Job to 

 Matthew Arnold, poets have repeatedly expressed the idea, 



" Time writes no wrinkle on thine azure brow, 

 Such as Creation's dawn beheld thou rollest now." 



The teaching of uniformitarian geology supported the old notion of 

 the poets. The change from 



" There where the long street roars, hath been 

 The silent stillness of a central sea," 



was attributed to an oscillation of the land, not a variation in the 

 level of the sea. The one level in nature that was taken as a 

 reliable constant was the mean sea level. Gradually, however, the 

 view has grown that Ordnance Datum is as inconstant a constant as 

 most earthly guides. Gradually the idea has been accepted that the 

 surface of the sea is no more an absolute plane than is Salisbury 

 Plain, but that it is heaped up against the margins of the continents 

 in a manner analogous to the upraising of water against the margin 

 of a basin. As soon as belief in the fixity of sea level was shattered, 

 many an apparently well established geological hypothesis was shown 

 to require modification or fresh proof, and many a geological principle 

 to require restatement. If the water level in the Central Pacific 

 could rise owing to a reduction in the attractive force of the land 

 masses on its margin (as for example by the sinking of an Antarctic 

 Continent) then the formation of Coral Atolls might be formed, not 

 by the slow subsidence of the sea floor, but by a gradual rise of 

 the sea surface, as water flowed into the Central Pacific from its 

 borders. Again, the apparent upraising of northern Scandinavia and 

 subsidence of southern Scandinavia might be due not to an actual 

 movement of the land, but to variation in the level of the two 

 halves of the' North Sea under the influence of changed winds and 



^ Ed. Suess, ' ' La Face de la Terre (Das Antlitz dor Erde). " Traduit sous la direction 

 de Emmanuel de Margerie avec un preface par Marcel Bertrand. Vol. I. pp. xv. 835., 

 gvo, with 2 coloured maps and 122 figures. Paris : Armand, Colin & Cie, 1897. Price, 

 2O fr. i 



