THE EEGION OF LAKES. 



521 



the so-called " year of the deluge," the level of the lake has been considerably 

 raised, islands have disappeared, inlets have been formed, forests destroyed, and 

 the hiehfoi, or neighbouring- meadows, converted into quagmires. These changes 

 are doubtless due to the extensive drainage operations that have been executed in 

 the surrounding districts, where 1,200 miles of drains now convey more water to 



Fig. 170. — Lakes and Makshes between the Volkhov and Dvina Basins. 



Scale 1 : 350,000. 



çe^QQ- 



96M0- 



L of P. 



2P/40 



L.ofG^ 



5 Miles. 



the lake than can be carried off by the Narova. Rapid encroachments have been 

 made on the north side, where a range of shifting dunes, 24 to 30 feet high, is 

 being constantly displaced northwards, leaving its site a prey to the advancing floods. 

 As the lake has a mean elevation of 95 feet above the sea, its outlet, the 

 Narova, descends somewhat precipitoush^ through a series of rapids to the Gulf of 

 Finland. Above Narva it forms two branches round the island of Kranholm, 



1G7 



