196 FLORIDA GEOLOGICAL SURVEY-15TH ANNUAL REPORT


 Two sandy clays occur at the "Y" on the Seaboard tracks as they enter Lake Wales. A section here is:

 Section of Clay Strata at Seaboard "Y" at Lake Wales.
 Feet
 Sand ......................................................... 3
 C lay, gray, sandy ................................................. 5
 C lay, black ...................................................... 3

 These two clays have similar properties. Both are sandy and are suited for nothing more than a very poor grade of common brick. The black, lower clay has the following physical properties:

 Physical Properties of Seaboard "Y" Black Clay, Lake Wales (Lab. No. o-5i).
 Plasticity.......................... Fair.
 Water of plasticity................. 19.50%
 Pore water ........................ 0.63%
 Shrinkage water .................. 18.87%
 Linear air shrinkage............... 6.90%
 Volume air shrinkage.............. 15.30%
 Modulus of rupture, average........ 135.3 pounds per square inch.
 Slaking test ....................... 24 hours.

 Fire tests:
Temperature. Linear Shr. A bsorption. Porosity. Color.
 Per Cent. Per Cent. Per Cent.
 950'C. 1.9 15.80 33.75 Cream.
 1050 2.5 15.58 34.40 Cream.
 1150 2.9 14.68 32.60 Cream.
 1190 2.9 14.54 31.60 Cream.

 A sample of clay from the Peace Valley Farms Company's property, near Winter Haven, was tested by the Bureau of Standards in 1914.1
 The results indicate that this clay is suitable only for. a poor grade of common brick. Its physical properties are:

 Physical Properties of Peace Palley Farms Clay, Bureau of Standards.
 (Sample No. 22).
 Plasticity, judged by feel........... Fair.
 Water of plasticity................. 24.9 %
 Linear air shrinkage............... 6.28%




 lSellards, E. H., Report on Tests for Paving Brick, Florida Geol. Survey Press Bulletin No. 7, 1915.
 (Bricks were made some twenty years ago from a whitish marly clay just east of Carter's on the Atlantic Coast Line, near the head of the Peace River, but the venture does not seem to have been a success. R. M. Harper.)