WATER SUPPLY OF EASTERN AND SOUTHERN FLORIDA. 185 
cene age at some distance inland and at an elevation of several 
feet above the present sea level. Oyster banks, probably of 
Pleistocene age, are exposed along a small drainage ditch on 
the farm of A. W. Corbett, four miles southwest of St. Augus¬ 
tine, at an elevation of at least 15 to 20 feet above the present 
sea level. That this depression during Pleistocene time was 
general for this part of the State is indicated by the evidence 
already given. 
The identification of the formations lying above the Vicksburg 
limestones and beneath the superficial sands, from well records 
alone is a matter of difficulty. This interval in St. Johns County 
is occupied largely by clays, although some sand, shell and rock 
strata occur. 
AREA OF ARTESIAN FLOW IN ST. JOHNS COUNTY. 
The areas of flowing and non-flowing wells in St. Johns 
County are indicated on the accompanying map. 
The shaded lines on the map indicate the area in which flow¬ 
ing artesian wells can be obtained in this county. As will be 
seen from the map the flowing area borders the Atlantic coast 
and the St. Johns River, and has a width along the coast and also 
along the St. Johns of from two or three to eight or ten miles. 
The flowing area extends inland following the streams. So far 
as present records show, a narrow strip extending north and 
south through the central part of the county is non-flowing. A 
fresh water spring is reported to occur in the ocean opposite 
Matanzas. Springs of this character represent the natural escape 
of the underground waters into the ocean. 
LOCAL DETAILS. 
ANASTASIA ISLAND. 
A six-inch well, drilled in 1895, at South Beach, on Antastasia 
Island, reached a total depth of 260 feet. A strong flow of sul¬ 
phur water was obtained-from this well. 
*U. S. Geol. Surv. Bull. 84, p. 125, 1892. 
