118 THE CLAYS OF AKKANSAS. 
there are large sand ridges of alluvial origin with a subsoil of yellow 
to buckshotty clay. In places these alluvial deposits extend 4 to 6 
miles back from the stream. Abandoned streams can likewise be 
traced by old channels, with alluvial deposits extending for a greater 
or less distance on both sides. Some of these old channels now form 
lakes. 
It appears that the surface of the country was originally very nearly 
level, with but slight depressions, sufficient to determine the loca- 
tion of the drainage streams. Repeated overflows carried large 
quantities of alluvium, which was deposited as sand ridges near the 
streams. The ridges farthest removed from the streams or aban- 
doned channels are all higher than the prairie lands. The soil of the 
prairie lands is generally a yellowish to gray clay, in places contain- 
ing more or less fine sand. The difference between the two soils is 
likewise marked by differences in species of virgin timber and differ- 
ences in the character of crops produced. The alluvial soil is generally 
much more fertile than the prairie soil. 
No clay products of any kind are manufactured in Jackson County. 
Brick clays are available at Grand Glaise, in the southwestern part 
of the county. The loam that forms the prairie lands back from 
the streams, especially in the central part of the county, could be 
made into common building brick. A clay subsoil that outcrops in 
the bank of White River at Newport is suitable for making a good 
building brick. 
JEFFERSON COUNTY. 
CLAY DEPOSITS. 
The greater part of Jefferson County is covered by alluvial deposits 
of Arkansas River and of Bayou Bartholomew. Running along the 
western edge of the county, however, is a strip of the Claiborne (?) 
formation (Eocene), having a width of 10 or 12 miles. In the river 
bottoms brick clays occur here and there and in some of the slashes 
there are occasional patches of clay available for the manufacture of 
cheap grades of pottery, but the best clays of the county are in the 
western tier of townships. At a place called White Bluff these 
Tertiary beds are well exposed on Arkansas River. The accom- 
panying section recorded at that place shows the relations of the 
clays to other beds. 
S< ction at White Bluff, on Arkansas River. 
Feet. 
1. Soil and sand 8 
2. Light-gray sandy day 9 
3. Light-pink clay with fossil leaves 8 
4. Laminated dark shaly clay 9 
