SECOND ANNUAL REPORT-MINERAL INDUSTRIES. 
245 
Diatomaceous earth is used largely as a polishing powder for 
which its hardness and fineness render it particularly applicable. It 
is also used in some scouring soaps, and to some extent in the manu¬ 
facture of dynamite as an absorbent for nitroglycerine. It is a good 
nonconductor of heat and hence is valuable for packing steam pipes, 
and to some extent for fire-proof material in general, including build¬ 
ing stone. 
LIME AND GROUND LIMESTONE. 
Lime or “quick lime” is chemically an oxide of calcium or of 
calcium and magnesium. It is made ordinarily by burning limestone, 
although shells and other calcium carbonates may be used for the same 
purpose. In the process of burning the carbon dioxide of the lime¬ 
stone is driven off leaving the oxide as lime. 
The Florida Lime Co. of Ocala in addition to the manufacture of 
lime has during the past year installed machinery for grinding the 
natural limestone. The limestone thus ground is designed for ap¬ 
plication to the soil to correct acidity. 1 Calcareous rocks and shell 
deposits suitable for grinding for this purpose are widely distributed 
in the State as indicated in the paper on Stratigraphic Geology in the 
preceding pages of this report. Limestones occur at or near the sur¬ 
face locally in Walton, Holmes, Jackson and the northern part of 
Washington Counties. Limestones of the Vicksburg group occur ex¬ 
tensively in central Florida (see map). The Miami oolitic limestone 
makes up an extensive formation running north and south from 
Miami and forming the east border of the Everglades. The Apalach¬ 
icola group including some compact limestones occurs extensively in 
parts of west Florida. The marls are usually of local occurrence and 
are restricted to no part of the State. Recent shell deposits are abun¬ 
dant on the coast and along some of the rivers. 
SAND-LIME BRICK. 
Five plants have been engaged during all or a part of the year in 
the manufacture of sand-lime brick. These are as follows: Seminole 
Pressed Brick Company, Jacksonville; The Florida White Pressed 
Brick Company, Jacksonville; The Bond Sandstone Brick Company, 
Lake Helen; Plant City Granite Brick Company, Plant City; and 
Florida Brick Company, Live Oak. The last named plant closed 
1 Material for correcting soil acidity. Press bulletin No. 78, Fla. Agri. Exp. 
Station, by A. W. Blair. Also Bulletin No. 93, p. 52, 1908. 
