SOME FLORIDA LAKES AND LAKE BASINS. 



123 



The total solids removed in solution through six other springs 

 of central Florida, expressed in tabular form, gives the following 

 results : 



Name of Spring. 



County. 



Blue Marion 



Blue Levy 



Ichetucknee Columbia 



Newland Suwannee 



Weekiwachee Hernando 



White Sulphur Hamilton 



Suwannee Suwannee 



As the basis of an estimate of the total solids removed annually 

 from the interior, let it be assumed, ( i ) that the average total solids 

 in spring water amount to as much as 219 parts per million, this 

 average being obtained from eight of the typical large springs of 

 central Florida; (2) that the annual escape of the underground 

 water approximates the annual in-take, amounting, as previously 

 estimated to 460,536,689 gallons per square mile. Upon these 

 estimates the mineral solids removed amount to a little more than 

 four hundred tons annually per square mile. 



Of the minerals thus removed, calcium carbonate or limestone 

 greatly predominates, exceeding the combined weight of all other 

 minerals. From the analyses it appears that magnesium carbonate, 

 magnesium and calcium sulphates are present in variable, although 

 usually limited, quantities. Chlorides are normally present in small 

 amount, although occasionally, as in the case of Perrian Spring, 

 tliey are exceptionally high. Silica is present in amounts varying 

 from 5 to 25.5 parts per million. Traces of phosphoric acid and of 

 iron and alumina are usually present. 



The several undetermined factors which enter into the above 

 estimates of mineral solids removed make it difficult to formulate 

 a concrete statement of the rate of lowering of the general surface 

 level. Nevertheless, such statements are desired and have a com- 

 parative value. Assuming for the rock removed, most of which is 



♦Organic matter is deducted from the total solids as given for Suwannee 

 Sulphur and White Sulphur Springs. The organic matter occurring in the 

 other springs is of small amounts and was not separately determined- Analyses 

 of the water of these springs were given in Bulletin No. i, pp. 72-75, 1908. 



