parts of the county. Water enters the formation in areas where it is at or near the surface in the central part of the peninsularand in places where it is overlain by permeable rocks that permit free downward percolation. Water also enters the.formation through drainage wells in Orange and Seminole counties. The Hawthorn formation contains relatively impervious strata that prevent or retard upward percolation of water from the Ocala. In some parts of the county this impervious material is absent or comparatively thin, or it may be fractured, permitting water from the Ocala limestone to reach the surface. On the development of one of the drainage canals north of Oviedo water under artesian pressure was encountered at a depth of about 15 to 20 feet. Water under artesian pressure is also encountered at depths of less than 50 feet under spring mounds in that locality. The spring mounds are domes about 50 to 100 feet in diameter and extending about 4 to 5 feet above the surface. They appear to be formed in places where the confining beds do not prevent some seepage of the artesian water to the surface. The water thus appearing at the surface supplies the overburden of peat with mpisture in excess of that in adjacent areas and thereby retards the rate of shrinkage in the peat at the spring, as compared with the shrinkage in adjacent areas.
The area in which flowing wells may be obtained includes all of the lowland bordering the St. Jolhns River, the Econlockhatchee River, Lake Monroe, Lake Jessup, and Lake Harney. In the vicinity of Sanford the
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