the North Sea with the.Baltic along the line of the lakes Malar, Hjelmaf 
and Wenem. Those straits were open when the Danish fishermen occupied 
the sites of the shell-mounds, and the date of these shell-heaps is proved 
by the fauna to be fully as recent as that of the lake-dwellings. Indeed, 
in one of the oldest of them (near Kallundborg) objects of bronze have 
been found. Since this date — which was hardly more than 3,000 years 
ago — the straits referred to have been closed, and the land at Linde, in 
Sweden, has risen 230 feet. 
I may add, that the coasts of Norway have risen 600 feet since the 
temperature of the adjacent seas was very nearly what it is to-day. 
If these changes have occurred within so recent a period, why should 
there be any difficulty about the Straits of Dover ? The elevation of the 
land at Linde must have occurred since bronze implements found their way 
to Denmark — that is to say, within 3,000 or 3,500 years. 
