152 
FLORIDA GEOLOGICAL SURVEY—THIRD ANNUAL REPORT. 
Feet. 
Limestone ...... 410- 495 
Dense light brown “limestone. Temperature of water 79° at 
520 feet. Head 42 feet above sea at 520 feet. Flow of 4860 
gallons per minute at 520 feet.. 495- 520 
White “chalk,” green clay, dark porous limestone.. 520- 557 
Limestone ..... 557- 675 
Hard rock ... 675- 685 
Limestone . 685- 770 
Limestone, gray to light yellow . 770- 960 
Thin stratum of hard limestone, followed by limestone similar 
to above. Temperature of water 800 at mo feet. Flow 
of 6075 gallons per minute at mo feet... 960-1110 
Hard rock, said to be standstone, with some flint ..mo-1140 
Material not recorded .......1140-1170 
“Sandstone,” followed by limestone. Temperature of water 85° 
at 1225 feet . 1170-1225 
Limestone as above . 1225-1278 
“Sandstone.” Sample not seen .1278-1293 
Fossiliferous limestone . 1293-1340 
Fossiliferous limestone, easily penetrated. Temperature of 
water 86° at 1340 feet . 1340-1390 
Denser limestone .1390-1440 
The following is a log of the well of Mr. W. J. Sherman. 
This well was drilled by the owner in 1886 and is 210 feet deep. 
It is two inches in diameter and is cased no feet. The head is 
reported to be 32 feet above sea and the flow about 80 gallons per 
minute. 
Feet. 
Sand . 0 - 5 
Clay .... 5 - 6 
White quicksand . 6 - 11 
Clay . 11 - 11^2 
Coarse pebbles and some shells ... 1V/2- 43 
Coarse gray to greenish sands, water-bearing; slight flow. ... 43 - 45 
White plastic clay and fine sand. 45 - 90 
Greenish clay, very compact. 90 -142 
Hard rock .142 -143 
Greenish clay with a mixture of black sand ..143 -172 
Hard rock; water rises 32 to 37 feet above sea..172 -180 
White chalk rock (probably Vicksburg) . .180 -210 
SWITZERLAND. 
Switzerland is located in the area of artesian flow on the St. 
Johns River in the northwestern part of St. Johns County. Wells 
at this locality reach a depth of from 350 to 500 feet, and the water 
is reported to rise 29 to 30 feet above the surface. 
