THE FLORIDA PHOSPHATE DEPOSITS.

Pale yellow incoherent sands ............................ 5 to Io feet
Red clayey sands5................................... to io feet
Phosphate-bearing formation.........................10 to 25 feet
Limestone at bottom of pit.
The phosphate matrix consists of gray sands, yellow, buff and blue clays, and phosphate rock. At one place in this pit a stratum of gray sand !/ to 2 feet thick is seen interbedded with the phosphate rock.
The incline leading to a new pit being opened up by M. C. and T. A. Thompson near Neal gave the following section:
Pale yellow incoherent sands .............................. 5 to 10 feet
Red clayey sands................................... 7 to io feet
Gray phosphatic sands (exposed)........................ 15 feet
The gray-sands give place laterally to phosphate rock.
Pit No. 2 of the Cummer Lumber Company is perhaps the largest single pit in operation in the hard rock phosphate section. This pit is reported to include at the present time about thirteen acres. Pit No. of this Company, one mile west of Newberry, gives an exposure of the sandstone and flint pebble conglomerate already referred to as occurring occasionally in the hard rock de!Posits. The pebbles are round and more or less flattened. They vary in size from very small pebbles to pebbles weighing five to seven pounds.
In the pit of the Union Phosphate Company at Tioga a considerable number of rounded elongate siliceous boulders occur. These vary in size, the largest approximating a ton in weight. They are embedded in the phosphate-bearing matrix.
The many other pits which are now being worked, or which have recently been abandoned, although varying much even within a single pit in details are in general much the same as those described.
The limestone in this county as a rule, lies relatively near the surface. In most instances the limestone is encountered before or very soon after reaching the water level. The phosphate is thus largely worked out by dry mining and dredges are not in use. The limestone is encountered at varying depths. One pit may show a great deal of limestone projecting as peaks, while another pit of equal depth near by may scarcely reach the limestone. Some of the limestone peaks project 15 to 25 feet above the general level of the bottom of the pit. The ph sphate-bearing matrix here as elsewlhere fills up the irregularities in the limestone. The top surface of the limestone is as elsewhere entirely

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