118 FLORIDA GEOLOGICAL SURVEY—THIRD ANNUAL REPORT. 
the well. In such cases the sand gains entrance or the well caves 
below the casing clogging or partly clogging the opening, thereby 
reducing or entirely stopping the flow. 
i 
NECESSITY OF GUARDING AGAINST WASTE OF ARTESIAN 
WATER. 
The records that have been given above indicate clearly that 
useless waste of water should not be permitted. An artesian well 
draws not on an inexhaustible supply of water from some remote 
source, but draws upon a relatively local supply which is appreci¬ 
ably affected by continued use. A well permitted to flow unin¬ 
terruptedly draws not only on the supply of the land on which 
it is located but affects also the supply of the adjacent land. A 
state, a community, or an individual that permits the useless and 
reckless waste of artesian water will ultimately find a most valuable 
asset impaired by extravagance, and possibly no longer adequate. 
It is urged by some well owners that to cut off a well or to 
stop the flow when not in use is unsafe as sand or other material 
may get into and clog the well. The flow of the well can be reduced 
to one-third or one-fourth its normal volume and the danger from 
the accumulation of sand, when there is such danger, guarded 
against. Moreover where wells are cased, as they should be to the 
Vicksburg Limestone, it is doubtful if there is danger of clogging 
and reducing or stopping the flow. A law restricting the waste 
of artesian water is urgently recommended. 
SIMPLE METHOD OF DETERMINING FLOW OF ARTESIAN 
WELLS. 
A simple method for measuring approximately the flow from 
an artesian well has been devised by Professor J. E. Todd, former¬ 
ly State Geologist of South Dakota. The following is Professor 
Todd’s method in full: 
“It is often desirable to know the amount of water delivered by 
an artesian well. Frequently a contract calls for a certain amount. 
It is also well to know whether the flow is diminishing and how 
much. 
“When a well is small, its flow may be measured easily with 
a watch and a gallon measure, or a keg or barrel of known capaci¬ 
ty, but for wells flowing over twenty or thirty gallons a minute, if 
is not so easy to determine with accuracy. 
“If the well is large it may be measured with a weir, but that is 
constructed only with considerable trouble. If the water runs in a 
