120 IN LOWER FLORIDA WILDS 



areas in the newer part of the great swamp. In 

 this connection the settlers make a distinction 

 founded on the depth of muck, and speak of the 

 "Upper Glades" and "Lower Glades." In the 

 upper (northern) part of the swamp the saw grass 

 is much more dense than elsewhere and it is said 

 that the Seminoles never attempt to cross that 

 section. 



Whenever Okeechobee becomes filled to over- 

 flowing the surplus water pours out and over the 

 Glades. The dense growth of saw grass and other 

 herbaceous vegetation prevents it from running 

 rapidly to the sea although there is a gradual fall 

 all the way. For this reason most of the region 

 becomes covered with water which moves slowly 

 seaward. When the water of Okeechobee is con- 

 fined within the lake the water slowly drains off 

 and the glades may become dry. The decaying 

 vegetation around the border of the lakes has 

 slowly built up the land. The outflowing water 

 has deposited a considerable amount of silt at the 

 rim, still further assisting in the land building. It 

 may seem strange that two such causes should 

 actually raise the level of these large bodies of 

 water, but before drainage operations were begun, 



