THE ARTESIAN WATER SUPPLY OF EASTERN FLORIDA.

Water is reported to flow from this depth. Below this stratum of rock IOO feet of blue marl with inclusions of several thin strata of shells is reported. In a sample from this stratum the sand was gray in color and the grains were round in outline. The black pebbles, smaller than those in the above stratum, occur also at this depth but may have dropped down from above. At
a depth of from 355 to 364 feet a very hard rock is reported, but no further notes were made of this and no samples kept. From
364 to 418 feet indurated gray sand and blue marl is reported and immediately below this is encountered a rock, apparently limestone, in which the water is reported to increase in head and in volume of flow as each hard layer is penetrated. From all information that could be gathered it seems probable that this limestone is the Vicksburg.
Exposures of clayey impure limestones are found along the St. Marys River at High Bluff about six miles and at Saw Pit
Bluff about two miles above the Atlantic Coast Line Railroad bridge; also at Chalk Bluff and at Orange Bluff near King's Ferry,
The section at Saw Pit Bluff (P1. 14, Fig. 3). is as follows:
Sticky blue clay with some soil.... ....................... 5 feet
Im pure lim estone ............................................ 5 feet
At Chalk Bluff about two miles above King's Ferry the following section was observed:
Sticky blue clay with some soil at top.....................2 feet
Calcareous clay resembling fullers earth.....................2 feet
W hite chalky material ....................................... I foot
Clay resembling fullers earth ............................... 2 feet
Going down the river from King's Ferry no rock or shell exposures are seen until Reed's Bluff near Crandall is reached. This bluff, which lies on the Florida side of the St. Marys River, is semi-circular in shape and is about three-fourths of a mile long. The following section was made near the middle of this bluff:
Incoherent pale yellow sands ............................ 20 to 40 feet
Oyster shell reef imbedded in fine sandy clay...........IO to I5 feet
Blue sands and sandy clays oxidizing yellow............O to 20 feet
The oyster reef in this section rests irregularly upon the undel lying sands, the base of the reef being IO to 20 feet above low

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