260 
FLORIDA STATE EEOFOGICAF SURVEY. 
by shovel into “.dummyV cars and is drawn either by cable or by small 
engine to the plant nearby. 
At the plant the fullers earth is taken to the store house. The 
larger pieces are first broken by pick or sledge and the material then 
passed through, a crusher. After passing through the crusher the ma¬ 
terial, now broken into pieces, one to two or three inches in size, is 
fed automatically into a drying cylinder. These cylinders which are 
30 to 40 feet long- and five or six feet in diameter, revolve slowly and 
by means of half cups set at an incline move the fullers earth forward 
with each revolution. A high temperature is not sought in the cylinder 
as used in Florida, the object being to remove the surface moisture 
from the clay. The fullers earth passes through the cylinder at the 
rate of possibly one ton an hour, each piece of clay occupying fifteen 
to twenty minutes in transit. The fullers earth upon dropping from 
the cylinders after drying is carried to a storage bin, and is there fed 
to the mills for grinding as needed. Two kinds of mills are in use. 
One of these consists of a horizontally revolving cylinder in which the 
earth is ground fine by a gravity ball. From this mill the ground 
fullers earth is carried to a jig which separates the earth into two 
grades of fineness. The second kind of mill, which is perhaps the 
mill most frequently used, grinds and delivers the earth in mixed 
grades. The ground material in this case is passed through bolters 
and separated into the grades desired for commercial purposes. After 
bolting, the earth is sacked for shipment and is labelled according to 
the degree of fineness. The grade most used in refining mineral oils 
is about 30-60, by which is meant fullers earth ground to a fineness 
which permits it to pass through a thirty mesh screen but not suffic¬ 
ient to permit it to pass a sixty mesh screen. The finer grades find 
other uses. 
Production of Fullers Earth During 1908Three plants were 
engaged in mining fullers earth during 1908. These were the Owl 
Commercial Co., Quincy; The Southern Fullers Earth Co., Mt. Pleas¬ 
ant, and The Atlantic Refining Co., Ellenton, Florida. The total 
amount of fullers earth mined in the State during 1908 as reported to 
the Survey by the producers was 22,932 short tons. The product is 
used principally in the United States, although approximately 5 per 
cent of the 1908 product was exported to foreign markets. 
Fullers earth in America was first discovered at Quincy, Florida. 
Previous to that date all of the fullers earth used in this country was 
imported from England. Following its discovery in Florida fullers earth 
deposits were located in several other States. During 1907 seven 
States are reported to have produced fullers earth. 1 These are in 
1 Mineral Resources, U. S. Geol. Survey for 1907, p. 733, 1908. 
