VIII RIVERS AND LAKES 821 
that in-the direction from Lucerne towards 
Rapperschwyl] there has been an elevation of 
the land, which has dammed up the valleys 
and thus turned parts of the Aa and the 
Reuss into lakes — the two branches of the 
Lake of Lucerne known as the Alpnach See 
and: Urner See. 
During the earthquakes of 1819 while part 
of the Runn of Cutch, 2000 square miles in 
area, sunk several feet, a ridge of land, called 
by the natives the Ulla-Bund or “the wall of 
God,” thirty miles long, and in parts sixteen 
miles wide, was raised across an ancient arm 
of the Indus, and turned it temporarily into 
a lake. 
In considering the great Italian lakes, 
which descend far below the sea level, we 
must remember that the Valley of the Po is a 
continuation of the Adriatic, now filled up 
and converted into land, by the materials 
brought down from the Alps. Hence we are 
tempted to ask whether the lakes may not 
be remains of the ancient sea which once 
occupied the whole plain. Moreover just as 
the Seals of Lake Baikal in Siberia carry us 
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