A PRELIMINARY REPORT ON CLAYS OF FLORIDA 265

Putnam County, 14, 28, 29, 31, 38, 39, 63, Shuttle eyes, 106
 197, 240 Siderite, 74, 81
Pyrite, 74, 81, 87 Silica, 65, 78-80
Pyrolusite, 77 Silicates, 64, 65, 71, 72, 82, 83, 90
Pyrophyllite, 72 Sink-holes, 109, 110, 115
 Sillimanite, 78
 Q Slaking of clay, 91, 100
Quarterman, B. S., 240 Slip clay, 106
Quartz, 14, 66, 72, 73, 80, 81, 218 Soda, 65, 76, 78, 83 Quincy, 160, 161 Soil, definition of clay, 65
Quintette, 145, 154 Soluble salts in clay, 85-88, 193
 Somers, R. E., 71, 73, 76-78, 232
 R Soper, E. K., 69, 70
Railroad ballast, 106 South Carolina, white clays of, 216, 226
Ranson, Robert, 17 Southern Farm Land Co., 157
Rectorite, 72 Spanish settlements, 242
Refractory clay, 70 Spark plugs, 232
Residual clay, 66, 67, 69, 72, 110, 111 Staley, H. F., 85, 87 Retorts, 106 State Hospital, Chattahoochee, 158-162
Reusch, H., 72 Statistics on mineral production, 14-23
Richbourg, D. J., 124 Stoneware (clay), 104, 145, 154, 214, 243
Richmond, kaolin, 236 (see Okahumpka) Stoutamire, J. D., 179 Ries, H., 63-65, 67, 69, 72, 79, 81, 82, 84, Stoutamire, W. B., 179, 180
 89, 92, 93, 96, 98, 179, 180, 218-222, Strait, Allen, 63
 259 Stratigraphy, 107
Road metal, 106 Strength of clay, 99, 102-103
Roofing tile, 145, 154 Sulphur, 74, 78, 79, 83, 85
Royston, Ed, 159 Sumter County, 206, 217
Rutile, 76, 78, 84 Suwannee County, 111, 207, 217
 S
Saggers, 106, 244 T
St. Johns County, 200-201 Tallahassee Pressed Brick Co., 117, 164
Sand and gravel, production of, 22 Tampa Brick Co., 171 Sand-lime brick, 22, 247 Tampa formation, 108, 112, 166, 170-172
Santa Rosa County, 201-205 Taylor, C. B., 63
Schaffer, I. L., 153 Tedder, C. H., 63
Schurecht, H. G., 77 Temple Terrace, 171
Schrotterite, 72 Tensile strength of clay, 102
Scove kilns, 202, 204 Terra-cotta, 104-106, 145, 154, 250
Sections indicating thickness of kaolin, Texture of clay, 91
 236, 237, 240 Thermoelectric pyrometer, 97
Sedimentary clay, 66-68, 72 Thickness of kaolin formation, 236, 237,
Sedimentary kaolin, 117, 121, 193, 216- 240
 241, 244, 245, 258-260 Thompson, R. W., 213
 Seger cones, 96-98, 135, 244, 255-257 Tile, 106, 243, 250, 258 Selenite, 76 Titanic acid, 78
 Sellards, E. H., 28, 29, 109, 125, 138, 191, Titanite, 78
 196, 207, 217, 218, 221-223, 235, 259, Titanium, (76), 80, 84 260 Tombstones, clay, 106
Sericite, 73 Tourmaline, 78
Serpentine, 65 Trail Ridge, 135
Sewer pipe, 106, 247, 248 Transported clays, 70
Shale, 70 Transverse strength of clays, 102
Shell Bluff, 157 Turpentine cups, 106, 127, 138, 154, 214,
Short clay, 89 243, 248
Shrinkage of clay, 91-93, 100, 101 Tuyeres, 106