146 FLORIDA GEOLOGICAL SURVEY SIXTH ANNUAL REPORT. 



road some years ago is 64 feet. By accurate levels run by one of the topograph- 

 ical parties of the Geological Survey working in this section during the winter of 

 1890-91 the elevation of the water was found to be 58 feet, thus showing that the 

 lake had been changing elevation ; and about two weeks ago I was informed that 

 Alachua Lake had disappeared entirely, that only small pools remained and the 

 usual amount immediately around the sink." 



The early geological history of that section of Alachua County 

 now occupied by these larger basins and lakes was apparently as 

 follows : Originally the surface runoff from southeastern Alachua 

 County made its way through Orange Creek and the Ocklawaha 

 River into the St, Johns River. These streams were then heading 



Fig. 38. — Sketch map of Hogtown Prairie and surroundings, illustrat- 

 ing a stage in the development of a solution basin. From the 

 Arredondo topographic sheet, U. S. Geol. Survey. The 60-foot 

 contour line borders the prairie. 



back in the plateau region of Alachua County, and were fed both 

 by the surface runoff and by the numerous small springs issuing 

 from the clays and sands of the Apalachicola group underlying the 



