WATER SUPPLY OF WEST FLORIDA. 
115 
being affected by underground solution is evident from the occa¬ 
sional sink holes which have formed most of which are filled with 
water forming lakes. Geologically speaking Holmes Valley is a 
temporary phase of land development and will retreat southward 
following the retreat of the escarpment bordering the plateau. 
ELEVATIONS. 
There are very few points in Washington county the elevations 
of which have been determined and these occur along the Louisville 
and Nashville Eailroad traversing the northern edge of the county. 
No points in the interior have been determined accurately. Cary- 
ville in the northwestern corner is given as 72 feet above sea; Boni 
fay (on the boundary between Holmes and Washington counties) 
120 feet, and Chipley 113 feet. The red hills of this northern area 
reach their climax in the vicinity of Orange Hill. Barometric 
readings show the hill to be afi least 100 feet above the station at 
Chipley. 
DRAINAGE. 
The western part of Washington county is drained principally 
by Holmes Creek and its tributary streams together with Pine Log 
Creek and its tributaries. Both of these streams flow into the Choc- 
tawhatchee Biver. Econfina Biver in the southern portion empties 
into the North Arm of St. Andrews Bay and receives part of the 
surface drainage of this section. In addition subterranean drain 
age in this county plays a very important part. Sink holes, ponds, 
small lakes and many depressions which owe their origin to the dis¬ 
solution of the underlying limestones are in evidence over the 
northern portion of the county. These natural solution cavities and 
basins receive the surface water which passes through these chan¬ 
nels into the underground water supplies. Falling Water Sink, 
into which a small stream empties, has already been mentioned. 
Blue Pond Sink, so-called from the characteristic blue color of lime¬ 
stone waters, is also a well known locality. This pond is about 
seven miles south of Orange Hill. Porter’s Pond is a larger body 
of water, but in all probability is of lime-sink origin. 
AREA OF ARTESIAN FLOW. 
Flowing artesian wells are obtained in Washington county on 
the lower land bordering the Gulf, and for an undetermined dis¬ 
tance inland along the streams. A deep well drilled about six miles 
