BIBLIOGRAPHY OR FLORIDA PHOSPHATES. 
i 9 
1892. Willis, Edward: 
Phosphate Rock in Report on Mineral Industries in the 
United States at the Eleventh Census, 1890, pp. 681-691, 
1892. 
The phosphates of Florida are described on pp. 687- 
689. 
1893. Davidson, Walter B. M. : 
Notes on the Geological Origin of Phosphate of Lime in 
the United States and Canada. Am. Inst. Min. Eng. 
Trans. XXI, pp. 139-157, 1893. Read before the Amer¬ 
ican Institute of Mining Engineers at the Baltimore 
meeting, February, 1892. 
The phosphates of Florida are derived from the leach¬ 
ing of Vicksburg Limestone. The pebble phosphate of 
Southern Florida is regarded as secondary deposits, hav¬ 
ing reached its present location by river action. 
1893. EeBaron, J. Francis : 
Discussion following paper by Walter B. M. Davidson on 
The Geological Origin of Phosphate of Lime in the 
United States and Canada. Amer. Inst. Min. Eng. 
Baltimore meeting, February, 1892, published 1893.* 
This paper has not been seen but contains, according to 
Capt. EeBaron (personal letter of May 23, 1911), an 
account of the discovery of the pebble phosphate on Peace 
Creek in 1881. 
1893. Persons, A. A.: 
Soils and Fertilizers. Fla. Agri. Exp. Station, Bull. No.. 
20, pp. 16-17, 1893. 
1893. Eldridge, George H.: 
A Preliminary Sketch of the Phosphates of Florida. Am. 
Inst., Min. Eng. Trans. XXI, pp. 196-231, 1893. Read 
before the American Institute of Mining Engineers at 
the Baltimore meeting, February, 1892. 
The hard rock phosphates are assumed to have origi¬ 
nated from deposits of guano or from phosphate through¬ 
out the Vicksburg Limestone. 
