LAKES AND SHORES 



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stone Lake, 7,738 feet above sea-level, 

 and with an area of 140 square miles, 

 is the highest lake of much size in the 

 United States. Lake Titicaca, in South 

 America, is both higher (12,500 feet) 

 and larger (3,200 square miles). A few 

 great lakes are below sea-level. This 

 is true of the Caspian Sea, the Dead Sea, 

 and the Sea of Tiberias, the surfaces of 

 which are 85, 1,268, and 682 feet, 

 respectively, below sea-level. Their 

 elevation is commonly expressed thus: 

 -85, -1,268, and -682 feet. While the 

 bottoms of some lakes are below sea- 

 level, the bottoms of most are well 

 above it. 



Deep as some of the lakes are, the 

 shape of their basins is often very 

 different from that which might be 

 imagined from the mere statement of 

 the depths. Fig. 149 represents the 

 cross-sections of the basins of some of 

 the Great Lakes, but the diagrams 

 exaggerate the depth about twenty 

 times. The basins of many smaller 

 lakes are much more striking in cross- 

 section. 



Volume. The volume of water in 

 all lakes is insignificant when compared 

 with that of the sea. If the water of 

 all of them were poured into the ocean, 

 its surface would probably not rise two feet. 



Movements of lake water. All lakes are affected by waves, and 

 the water of many lakes moves in other ways also. In some there 

 are more or less well-defined currents, and in the larger lakes there 

 are slight changes of level from time to time, as the result of changes 

 in atmospheric pressure. 



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