Rr EE 
Notices of the Floridas, &c. 125 
A rolling tract of comparatively elevated si ok a’ 
continuation of Georgia and Alabama ridges, passes in an 
eastern direction, through the centre and pd cae part of 
West Florida, thence bends to the south-east into East 
Florida, dividing the waters that fall into the St. Johns and 
Gulf of Mexico and terminating between the Bay of Espi- 
ritu Santo and Charlotte harbour, and occupying in Flori- 
da; an extent of near 400 miles, with an average width of 
thirty. It presents the most diversified scenery afforded in 
the southern part of this country, an alternation of hills often 
of considerable elevation, and good soil, lakes, extensive 
prairies, savannas and pine plains S. 
This rolling district is principally of secondary fornia 
tion. Ledges and beds of limestone and siliceous rock 
appear in many parts. Numerous sinks, caves and subter- 
ranean water courses peculiar to calcareous tracts indicate 
a basis of limestone This rock occurs in sinks or circular 
tunnel shaped basins, generally very steep, and often of 
considerable depth, probably occasioned Py a passage 
opened by water into limestone caves—these sinks are nu- 
merous and observed in every part of the hilly country of 
Florida, Some have ie ai walls of limestone, 
ers have wells of pure water, Near t he Indian village of 
lar, vertical, and well stata it was filled with pure — 
Sinks border most of the lakes and savannas, afford 
outlet for the waters. In a section of the hilly dares of 
East Florida called “Alachua, I visited a sink filled with 
water, covering an acre. It is the outlet of a mill-stream 
that winds through a handsome prairie, and plunging into 
the rocky basin takes a subterranean course—ledges of 
calcareous and siliceous shell rock formed the banks of ea 
pool. Rocks in situ and detached, enclosing in a w 
siliceous matrix, siliceous petrifactions of marine shells 
were frequently noticed in this vicinity. This mineral 
gives fire copiously with steel, and no effervescence is pro- 
duced by acids applied to a recent fracture, and on minute 
division it appears entirely siliceous. A siliceous petrifac- 
tion of madrepores retaining no calcareous particle, but the 
cells perfect, and the stone white as coral rock in its na- 
