Of Western Europe. 1 7 



is the urus. But the oyster is no longer found in the 

 brackish water of the Baltic, and the muscle and other 

 shell-fish now reach there only one-third of the size that 

 is shown in these refuse heaps, and which they still at- 

 tain in the ocean. But it is known that, at no remote 

 period, ocean currents swept through Denmark in straits 

 now closed, and Sweden has been gradually rising at the 

 rate of two feet in a century in the southern part, and 

 five feet in a century in the north. The shores of Den- 

 mark, however, it is said, rise only at the rate of two 

 or three inches per century. If these shores have been 

 rising at the rate of two or three inches per century, the 

 shell heaps are now so near the level of the water that 

 they can not be credited with any antiquity exceeding 

 four thousand years. Hence, though they certainly be- 

 long to an earlier type of civilization, there seems no 

 reason for making them chronologically belong to a 

 more remote date than the more advanced races who 

 built the barrows and tumuli. This view is corroborated 

 by the fact that the remains of no extinct animal but the 

 urus are found here. 



One circumstance has been seized to give them a 

 more venerable antiquity. Denmark has been covered 

 with beech forest as long as we have any account of it. 

 But trunks of trees found in peat beds show that it was 

 preceded by oak, which in turn was preceded by for- 

 ests of pine. In a peat bed, under the trunk of a huge 

 pine, which itself lies under superimposed oak and 

 beech, a flint arrow-head has been found. And in the 

 shell heaps are found the bones of a bird {capercailzie) 

 which is supposed to have fed on pine buds. So with 

 guessers at the unknown duration of the unknown for- 



