58 UPRAISED STRATA IN SWEDEN AND NORWAY. CHAP. III. 



century to century, and the insensible rate of variation in. 

 the geographical distribution of organic beings in our own 

 times, we may presume that an extremely lengthened period 

 was required, even for so slight a modification in the range 

 of the. molluscous fauna, as that of which the evidence is 

 here brought to light. There are also other independent 

 reasons for suspecting that the antiquity of these deposits 

 may be indefinitely great as compared to the historical 

 period. I allude to their present elevation above the sea, 

 some of them rising, in Norway, to the height of 600 feet 

 or more. The upward movement now in progress in parts 

 of Norway and Sweden, extends, as I have elsewhere shown*, 

 throughout an area about 1000 miles north and south, and 

 for an unknown distance east and west, the amount of eleva 

 tion always increasing as we proceed towards the North Cape, 

 where it is said to equal five feet in a century. If we could 

 assume that there had been an average rise of two and a half 

 feet in each hundred years for the last fifty centuries, this 

 would give an elevation of 125 feet in that period. In other 

 words, it would follow that the shores, and a considerable 

 area of the former bed of the North Sea, had been uplifted 

 vertically to that amount, and converted into land in the 

 course of the last 5000 years. A mean rate of continuous 

 vertical elevation of two and a half feet in a century would, 

 I conceive, be a high average ; yet, even if this be assumed, 

 it would require 24,000 years for parts of the sea-coast of 

 Norway, where the post-tertiary marine strata occur, to attain 

 the height of 600 feet. 



* Principles, 9th ed. ch. xxx. 



