120 
FLORIDA STATE HORTICULTURAL SOCIETY. 
surface drainage; while a third part finds 
its way into the ground. 
Owing to the generally porous nature 
of the Florida formation, that part of the 
annual rainfall going directly into the 
ground is an unusually high percentage. 
While the part passing off as surface 
drainage is a correspondingly small part 
of the annual rainfall. 
It is not to ])e assumed, however, that 
all of that which passes into the earth is 
available again as artesian supply. The 
amount of water reaching the surface 
through an artesian well is necessarily 
less than that entering the ground, owing 
to friction in flow, to lack of completely 
pervious strata above and below and ow¬ 
ing to the evident fact that there is in all 
cases sources of escape for the water 
through channels other than the artesian 
wells. 
The area covered by the outcrop of any 
horizon will vary according to the thick¬ 
ness of the horizon, the topography of the 
area at which the outcrop occurs, and the 
dip of the strata. The dip of the Florida 
rocks is slight and the catchment area for 
any collecting horizon is therefore propor¬ 
tionately large. 
In addition to this usual or normal 
catchment area an added supply in some 
cases, probably of considerable importance 
is received from sinks reaching through 
to the conducting horizon. 
Of the great number of sinks through¬ 
out the State receiving regularly surface 
drainage many evidently reach no great 
distance downwards and the water after a 
more or less extended underground 
course reaches a river or otherwise re¬ 
turns to the surface. On the other hand 
it is equally evident that some of these 
sinks are waterways leading through, im¬ 
pervious strata and connecting with por¬ 
ous horizons, below which conduct water 
readily and are capable of becoming ar¬ 
tesian horizons Thus if the water of a 
sink is observed to rise to a definite level 
and to be unaffected by any amount of 
water going into it, and especially if the 
level of the water in the sink is found to 
agree practically with the level to which 
artesion water rises in borings in the im¬ 
mediate locality it becomes evident that 
the sink leads to the artesian horizon. The 
added supply of artesian water received 
through such sinks is doubtless very con¬ 
siderable. 
In this connection should be mentioned 
also a second unused artesian supply, 
namely the drainage of inland areas 
through deep borings. As is well known 
this plan of drainage involves sinking bor¬ 
ings to such depth as to encounter a con¬ 
ducting stratum which carries the water 
readily . Obviously the probabilities are 
that the water is thus being turned into a 
horizon capable of becoming an artesian 
supply horizon in some lower area of the 
State. Some such wells are recorded in 
which the water is turned directly into an 
artesian stratum, the artesian water ris¬ 
ing in fact within a few feet of the sur¬ 
face. Some of these wells present the un¬ 
ique feature of being, during wet weath¬ 
er drainage wells, and during dry weath¬ 
er, through the medium of pumps, irriga¬ 
tion wells. In these cases it is impossible 
from the data now at hand to affirm that 
the water thus added is available as an 
addition to the artesian supply at any 
nearby region of lower level having ar¬ 
tesian flow, but the inferences are very 
strong that the artesian supply is directly 
increased in this way. 
