No. 7. — The Topography of Florida, hy N. S. Shaler. With a 

 Note hy Alexander Agassiz. 



[Published by Permission of the Director of the U. S. Geological Survey.] 



Both in its general form and in the detail of its surface, Florida pre- 

 sents many interesting features. I propose in tiie following pages to 

 pass in general review the more important topographic elements of this 

 peninsula, and to consider the information which they give us as to the 

 general history of the continent. 



The peninsula of Florida, as is readily seen by glancing at an ordinary 

 map, forms a salient on the coast hue which departs widely in its gen- 

 eral character from all the other great capes of the continent. The pre- 

 vailing trends of the eastern coast are from northeast to southwest. 

 This projection extends in a general northwest and southeast direction. 

 All the other greater peninsulas of the continent are distinctly moun- 

 tainous in their character. This of Florida is formed of low lands, rising 

 as a broad fold from the deep water on either side to a vast ridge, the 

 top of which is relatively very tiat, there being no indications of true 

 mountain folding in any part of the area. All the other great penin- 

 sulas of the continent, except that of Yucatan, which in certain ways 

 resembles Florida and may be causatively connected with it, are com- 

 posed of old rocks. The last named salient is made up altogether of 

 very recent strata. 



The detailed topography of Florida is almost as anomalous as its gen- 

 eral configuration. Tlie region of the Everglades in the southern part 

 of the peninsula, and that known p.s the " Lake District " in the north- 

 ern, are both eminently peculiar in their configuration, having, so far as 

 I am informed, no likeness in any other part of this countrv. 



The first question before us concerns the origin of the Florida uplift. 

 It will be observed that we have on the peninsula of Florida a very re- 

 markable ridge, which has grown up from the sea-floor to the altitude 

 of al)out five thousand feet ; and a somewhat similar elevation in the 

 archipelago of the Bahama Islands. Neither of these ridges has a 



VOL. -XVI. — NO 7. 



