152 FLORIDA GEOrLOGICAL, SURVEY-I5T1II ANNUAL REPORT


















 FiG. 22.-Gnerl Xiew of lIarrineau Hi r~ck P' ant, Quintette, Escambia County.

black color is due to the presence of organic matter which is completely burned off, leaving it a light-cream color at cone 010. Its physical properties are:
 Physical Properties of Dexland No. 6 (Lab. No. 0-25).
 Plasticity, judged by feel ............ Excellent.
 W ater of plasticity................. 26.90%
 Pore water ......................... 0.40%
 Shrinkage water ................... 26.42%
 Linear air shrinkage................ 10.8 %
 Volume air shrinkage............... 31.0 %
 Modulus of rupture, average........ 1021.1 pounds per square inch.
 Slaking test ....................... 24 hours.
 Steel hard at cone 010.
 Fire tests:
Temperature. Linear Shr. /bsorption. Porosity. Color.
 Per Cent. Per Cent. Per Cent.
 950'C. 0.8 16.22 40.50 Cream.
 1050 2.2 16.56 31.75 Cream.
 1150 2.2 12.80 27.50 Cream.
 1190 3.2 7.82 17.50 Gray.
 1230 3.2 7.95 17.80 Gray.
 1310 3.2 6.84 16.90 Gray.
 1370 4.2 4.72 12.95 Gray.
 1430 7.7 3.62 10.20 Gray.

 Clays having properties similar to the Dexland and Escambia Bay
clays are also found farther westward in the valley of the Perdido River.
 A reddish-pink, very smooth-textured, highly plastic clay occurs about three miles east of Muscogee in a cut on the Gulf, Florida and Alabama Railroad. The clay is cross-bedded and dips slightly to the westward. There are several strata alternating with thin beds of sand.