302 COSMOS- 



seas,* that without earthquakes, properly so called, the surface 

 of the Earth is capable of the same gentle and progressive 

 oscillations, as those which must have prevailed so generally 

 in the earliest ages, when the surface of the hardening crust 

 of the Earth was less compact than at present. 



The phenomena to which we Avould here direct attention 

 remind us of the instability of the present order of things, 

 and of the changes, to which the outlines and configuration of 

 continents are probably still subject at long intervals of time. 

 That which may scarcely be perceptible in one generation, 

 accumulates during periods of time, whose duration is revealed 

 to us by the movement of remote heavenly bodies. The 

 eastern coast of the Scandinavian Peninsula has probably 

 risen about 320 feet in the space of 8000 years; and in 

 12,000 years, if the movement be regular, parts of the bottom 

 of the sea which lie nearest the shores, and are in the present 

 day covered by nearly fifty fathoms of water, will come to the 

 surface and constitute dry land. But what are such intervals 

 of time compared to the length of the geonostic periods 

 revealed to us in the stratified series of formations, and in the 

 world of extinct and varying organisms ! We have hitherto 

 only considered the phenomena of elevation ; but the analogies 

 of observed facts lead us with equal justice to assume the 

 possibility of the depression of whole tracts of land. The 

 mean elevation of the non-mountainous parts of France amounts 

 to less than 480 feet. It would not, therefore, require any 

 long period of time compared with the old geognostic periods, 

 in which such great changes were brought about in the 

 interior of the Earth, to effect the permanent submersion of 

 the north-western part of Europe, and induce essential alter- 

 ations in its littoral relations. 



James C.) Eoss, for his Antarctic expedition, I urged the necessity of 

 causing marks to be cut in the rocks of the southern hemisphere, as had 

 already been done in Sweden and on the shores of the Caspian Sea. 

 Had this measure been adopted in the early voyages of Bougainville and 

 Cook, we should now know whether the secular relative changes in the 

 level of the seas and land, are to be considered as a general, or merely a 

 local natural phenomenon ; and whether a law of direction can be re- 

 cognized in the points which have simultaneous elevation or depression. 

 * On the elevation and depression of the bottom of the South Sea, 

 and the different areas of alternate movements, see Darwin's Journal t 

 pp. 557, 561-566. 



