FINLAND : GLACIAL ACTION. 



209 



elevation than the highest crests of the hills whence they came. After the 

 retreat of the glaciers the land must have gradually subsided, thus giving 

 access to the sea, which slowly penetrated eastwards to form the present Gulf 

 of Finland. But it is doubtful whether it ever subsided sufficiently to open a 

 channel between the White Sea and the Baltic. Some lakes, such as Ladosra, 

 contain marine Crustacea, showing that they were formerly inlets of the Baltic ; 

 but no banks of marine shell-fish occur till we reach the lower valley of the Dvina. 

 The subsidence was followed by an upheaval, which still continues, and 

 evidences of which are everywhere visible on the coast and in the interior : here 



Fig. 101. — Parallelism of the Finnish Lakes and Peat Beds. 

 Scale 1 : 440,000. 



2r^°E.ofP 



27"E.bfGr. 



5 Miles. 



old coast- lines and seaports, now lost amongst the fields ; there islands connected 

 with the mainland, or shoals which have in their turn become islands surrounded 

 by other shoals. The upward motion seems, however, to be much slower than 

 in Scandinavia. A mark engraved on the Han go headland was raised 9 inches 

 only in eighty-six years, although the island of Suur Tytters, south of Hogland, 

 has certainly been upheaved 12 inches in fifty years. 



Glacial Action. 



NowHEKE else in Europe are the erratic boulders more numerous or larger 

 than in Finland. Some are large enoug-h to shelter the houses built at their 

 foot, and at the outlets of certain valleys they form " seas of stone." Even 

 159 



