122 FLORIDA GEOLOGICAL SURVEY—THIRD ANNUAL REPORT. 
the center of the stream as before. The measurements may then 
be read from 'the table as before. 
“This method is also applicable to measuring the discharges of 
different pipes when water is distributed about a farm or in a city. 
“Pipes which have been cut in the usual way are frequently di¬ 
minished in diameter by the incurving of the edge of the pipe. 
This will diminish the flow, but how much can only be roughly 
estimated. It will be greater than that of a straight pipe having 
the exact diameter of the opening as reduced.” 
THE AREAS OF ARTESIAN FLOW IN FLORIDA 
The accompanying map, revised from a similar map published 
in Bulletin No. i, indicates in a general way the flowing and non- 
flowing areas of the State. In using such general maps it should be 
borne in mind that artesian water depends primarily upon the struc¬ 
ture of the underlying formations, and these are subject to varia¬ 
tions of which there may be no surface indications. Moreover a map 
on a small scale can not indicate local elevations which affect flow. 
Thus while the map indicates approximately the limits of flow the 
exact limits can be determined in most cases only by drilling. 
The shading on the map indicates those parts of the State in 
which flowing wells have been obtained. There are as will be 
seen three principal areas of flow as follows: the Atlantic Coast 
area, the 'Southern Gulf Coast area and the Western Gulf Coast 
area. 
The Atlantic Coast area is described in detail in the subsequent 
pages of this report. This flowing area includes much of Nassau 
and Duval Counties, and with the exception of local elevated areas 
all of St. Johns County; it follows the valley of the St. Johns 
River almost if not quite to the head waters, while a narrow strip 
reaches south along the Atlantic Coast for 250 to 300 miles. The 
artesian water bearing formation dips in passing to the south, be¬ 
ing reached at Palm Beach at the depth of about 1000 feet. In ad¬ 
dition to its increased depth the water at Palm Beach was found to 
be too salty to be used for household purposes. Between Palm 
Beach and Key West no wells have been drilled deep enough to 
reach this formation. The deep well drilled on Key Vaca by 
the Florida East Coast Railway terminated at 700 feet in quartz 
sands, with sandstones and clay in streaks, not having reached the 
Vicksburg Limestone.* , 
/ - - - — - —-—-- 
^Florida Geol. Survey, Second Annual Report, p. 205, 190-9. 
