of the Surface of the Earth. 119 



by the observations made by Darwin in the coral seas),* 

 that, without the occuiTence of any actual earthquake, the 

 surface of the earth is still subjected to the same gentle and 

 progressive oscillations, which were of such general occur- 

 rence in early periods, when the thickness of the indurated 

 crust of the earth was loss considerable. 



The phenomena on which I have now endeavoured to iix 

 attention, remind us of the mutability of the present order 

 of things, and of the changes which the outline and configu- 

 ration of continents have probably undergone in the course 

 of long intervals of time. That which is hardly perceptible 

 to immediately following generations, becomes accumulated 

 in pei'iods, of the length of Avhose duration a measure is af- 

 forded to us by the movement of the heavenly bodies. The 

 eastern coast of the Scandinavian Peninsula has probably 

 risen upw'ards of 340 English feet in eight thousand years ; 

 and if the movement should prove to be uniform, portions of 

 the bottom of the sea, which lie near the coast of the penin- 

 sula, and are at present still covered by a stratum of water 

 50 fathoms (Brassen) in thickness, will make their appearance 

 at the surface, and begin to be laid dry in twelve thousand 

 years. But Avhat is the shortness of these intei'vals of time, 

 when compared with the duration of geognostical periods, 

 which display to us tlie succession of formations, and the 

 hosts of entirely different extinct organisms ! In the same 

 manner as we have now been contemplating the phenomenon 

 of elevation, we may also, supported by the analogies of ob- 

 served facts, assume the possibility of a similar amount of 

 sinking, or, in other words, of the depression of whole tracts 

 of land. The mean height of the non-mountainous portion of 

 France does not quite amount to 480 French (511^ English) 

 feet. When compared with ancient geognostical periods, dur- 

 ing which greater changes took place in the interior of the 

 globe, a very long time would not therefore be requisite for 



* As to tlie sinking and rising of the bottom of tlic Soutli Sea, and tlio 

 various areas of alternate movements, vide Darwin's Journal, pp. 567 and 

 061-566. 



