114 FLORIDA GEOLOGICAL SURVEY—THIRD ANNUAL REPORT. 
wise increases. The head is in reality only a measure of the pres¬ 
sure. The amount of flow is within limits dependent 
upon the amount of pressure. Other conditions remaining the 
same an increased pressure will result in an increased flow. For 
the records regarding pressure it is necessary to rely chiefly upon 
the Jacksonville and St. Augustine wells already referred to. 
At 680 feet the pressure of the artesian water in the Jackson¬ 
ville well was 12 pounds per square inch, or sufficient pressure to 
cause the water to rise vertically in a pipe 27.72 feet. At 900 
feet the pressure as shown by the gauge was 15 pounds, or suffi¬ 
cient to cause the water to rise 34.65 feet. 
The Ponce de Leon Hotel well at St. Augustine affords valu¬ 
able information as to the possibility of obtaining increased head 
in this section of the State by drilling to greater depths. This 
well was drilled to a total depth of 1440 feet. A measure of the 
head was made at frequent intervals while drilling. The first 
considerable flow obtained at St. Augustine is under a pressure 
causing it to rise about 32 feet above sea. At the depth of 350 feet 
the head was found to have increased to 38 feet above sea. At 
the depth of 520 feet the head had increased to 42 feet, a total 
gain of io feet. The head at greater depths than 520 feet is not 
specifically recorded. 
INCREASED TEMPERATURE WITH INCREASED DEPTH. 
The temperature of the water at St. Augustine was found to 
increase with 'the depth. The temperature of the water in the 
Ponce de Leon well at the depth of 35 feet is reported as 62 de¬ 
grees F. At approximately 100 feet the temperature was 72 de¬ 
grees F. At 170 feet the temperature was 74 degrees F. The in¬ 
creased flow obtained at 177 feet showed a temperature of 76 de¬ 
grees F. At 520 feet the temperature of the water in the pipe was 
found to be 79 degrees F. At 1,110 feet the temperature was 80 
degrees F. Between 1,170 and 1,225 ^ eet water taken from the 
sand pump showed a temperature of 85 deprees F. Water taken 
from the sand pump between 1,340 and 1,390 feet showed a tem¬ 
perature of 86 degrees F. 
This record of the Ponce de Leon well at St. Augustine is 
supplemented by the record from the new city well at Jacksonville. 
In the Jacksonville well the following temperatures were recorded: 
At a depth of 498 feet the temperature of the water flowing 
from the pipe was 71 degrees F. At 635 feet the temperature was 
74 degrees F. At 900 feet the temperature still registered 74 de¬ 
grees' F. These measurements made as the water escapes frdm 
