146 
FLORIDA STATE GEOLOGICAL SURVEY. 
INCREASED FLOW OF ARTESIAN WEEDS WITH INCREASED 
DEPTH. 
As a rule, the amount of flow or yield of wells in Eastern 
Florida increases with depth. To this rule there are, doubtless, 
exceptions, since the amount of flow, in all cases, depends upon 
the variable structure of the rock through which the drill passes. 
As illustrations of increased flow with increased depth, the follow¬ 
ing may be cited: 
In the new city well at Jacksonville, well No. 10 of the city 
water supply, the first flow obtained was a light flow of 5 gallons 
per minute at a depth of 270 feet. At a depth of 498 feet the 
flow increased to 112 gallons per minute. Upon reaching the 
Vicksburg Limestone, at a depth of 510 feet, the flow increased 
to 200 gallons per minute. The flow at the depth of 635 feet was 
found to be 500 gallons per minute. At 900 feet the flow was 
about 900 gallons per minute. At 980 feet, the full depth of the 
well, the flow was from 1,500 to 2,000 gallons per minute. For 
the detailed measurements of flow on this well the Survey is 
indebted to the drillers, the Hughes Specialty Well Drilling Com¬ 
pany of Charleston, South Carolina. 
A like increase of flow is shown by the Ponce de Leon well in 
St. Johns County, the measurements of which were kept, and have 
been kindly supplied by Messrs. McGuire and McDonald, con¬ 
tractors. The first flow in this well of 50 gallons per minute was 
obtained at a depth of 170 feet. At 177 feet the flow increased to 
350 gallons per minute. At 410 feet the flow was 2,083 gallons. 
At 520 feet the flow had increased to 4,860 gallons. At 1,110 feet 
the flow was 6,075 gallons. The well was continued to a total 
depth of 1,440 feet. The record of the well, however, contains no 
mention of increased flow below 1,110 feet. While exact measure¬ 
ments, like those given above, are seldom made; the drillers, with 
few exceptions, report increased flow with increased depth. 
INCREASED HEAD WITH INCREASED DEPTH. 
Not only does the amount of flow of the water in this section 
of the State increase with increased depth, but the head or pres- 
