Notices of the FloridaSf ^c. 123 



in all the salt creeks of Florida. I observed at Fort 

 George, mural precipices of soft ferruginous sandstone ele- 

 vated considerably above the waters of an adjacent sal 

 creek; they are composed of sand, sea mud, and oxide oi 

 iron indurated ; similar rocks are formed on other parts of 

 the coast. 



Extensive beds of shell rock, of a peculiar character, oc- 

 cupy the borders of the ocean, in various places from the 

 river St. Johns to Cape Florida. They are composed of 

 unmineralized marine shells, of species common to our 

 coast, mostly small bivalves, whole and in minute division, 

 connected by calcareous cement. I examined this rock 

 on the isle of Anastasia opposite St. Augustine where it ex- 

 tends for miles, rising twenty feet above the sea and of un- 

 known depth. It has been penetrated about thirty feet. 

 In these quarries, horizontal strata of shell rock of sufficient 

 thickness and solidity for good building stone, alternate with 

 narrow parallel beds of larger and mostly unbroken shells, 

 but slightl}' connected. Hatchets are used in squaring the 

 stone. Lime is made from this material, of a quality infe- 

 rior to ordinary stone lime. 



The large Spanish fort, and most of the public and pri- 

 vate buildings of St. Augustine, are constructed of this 

 stone. The rock extends in places into the sea, with su- 

 perincumbent beds of new shells of the same character. 



Similar shell rock is found on the continent in several 

 places. 



The eastern coast of Florida is lined with high sand-blufts, 

 surmounted by low entangled thickets composed princi- 

 pally of evergreens ; dwarf live oak, small bay and cabbage 

 trees, and myrtle, predominate. The saco palmetto infests 

 the islands and adjacent continent — it has a large body re- 

 cumbent on the ground terminating in tufts of fan-like 

 leaves. 



There is but little cultivable land on the isles and pe- 

 ninsulas below the St. Johns. Excepting narrow strips of 

 hammock, the general character of the southern Florida 

 sea-board is pine barren. Graham's Swamp, one of the 

 largest of the hammocks, extends thirty miles between 

 Matanzie inlet and Mocca, with an average width of a mile ; 

 its rich vegetable soil has a marl basis, and will be valuable 

 if it can be drained. About Mocca, and Indian river, there 



