SOME FLORIDA LAKES AND LAKE BASINS.7

est during the rainy season when the lake is receiving a large amount of surface drainage.
Approximate me asurements of the water level in Alligator Lake near Lake City have also been made., This is one of the smaller basins and the measurements indicate that the level of the water in the lake stands appreciably above the underground water level. In this instance the measurements of the water level and the lake level were made at different seasons of the year and the results can be only approximately compared. The data on this lake are as follows: Levels made by Professor N. H. Cox, on June i9, 1903. showed that the water in Alligator Lake stood 94.22. feet below theUnion Depot at Lake City.
The lake at the time the levels were made was at medium full stage. The water of the Lake City public well located near, and on about the same level as the depot was f ound at the time the well was completed in 1907 to stand 134 feet from the surface. Allowing for any correction that it might be necessary -to make owing to the fact that the measurements of lake level and ground water level were not made at the same time it would still seem that the lake basin in this instance stands somewhat -above the water level. The drainage of this lake by wells should be possible pro vided the underlying limestone at this locality proves to be sufficiently porous and cavernous to conduct water readily.
SUMMARY.
The basins of the temporary lakes have their origin in erosion by solution and by mechanical wash. Some of them appear to represent the enlarged valleys of what was originally a small stream. Sinks form along these streams diverting the course of the water into the underlying limestones. Other basins originate from sinks in no way connected with stream valleys. The origin of the sink was due primarily to solution in the limestone. After the sink is formed the general level of the surrounding area is lowered somewhat by mechanical wash, the material being carried into the sink. Subsequently other sinks form in the immediate vicinity. The formation of these new sinks is due also to solution. The large amount of water which entered the limestone from the first sink facilitates solution and results in the formation of additional sinks. The continuance of this process through a long period of time results in the development of the large basins occupied by these lakes. From their manner of development it follows that the'steepest bluffs

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