SEBASTIAN COUNTY. 213 
cene age. The material forming these terraces are yellowish, red- 
dish, and lead-colored loams, clays, sands, and gravels. They lie in 
horizontal beds, but have been cut and more or less mutilated by 
erosion over the whole surface and by streams that cross them to 
enter Arkansas River. These Pleistocene deposits cover most of the 
plain on which the city of Fort Smith stands, and the peninsula 
extending northeastward toward Van Buren, where fragments of 
them occur here and there along the river east of Fort Smith. The 
clays of this series are exposed in what may be regarded as a typical 
section along the railway near the Ketcham iron works and at other 
points south of the city. The uppermost bed is a yellowish clay, in 
some places more or less mottled and in others containing small, fria- 
able nodules of iron. Although its characteristic color is yellow, 
this bed is in some places ashen gray and in others bright red. 
In the typical section just mentioned the next bed below the yel- 
low clay loam is a dark-red clay which contains a good deal of sand 
and which is about 10 feet thick. Below it is a bed about 1 foot 
thick of deep-red to chocolate-colored clay, and below lies a bed of 
fine sand. The bottom of the sand is not exposed. • The thickness 
and quality of these beds varies greatly; the yellow loam is entirely 
wanting in many places, having been removed by erosion, while the 
red clay may contain occasional beds of sand. 
It can not be positively stated that pottery clays do or do not 
exist in these Pleistocene river terraces, but the nature of the beds 
seen is favorable to the occurrence in them of pockets of pottery 
clays. In these terraces or second bottoms extensive deposits of 
brick earth are found, both in Sebastian and in adjoining counties. 
RECENT ALLUVIUM. 
The Pleistocene terraces referred to above are distinct from the 
river-bottom silts. The latter stand at a lower level and are usually 
less brilliantly colored. No pottery clays are now known in the bot- 
tom, but it is possible that they may occur there. As a rule the allu- 
vial deposits are silts and sands rather than clays, and such pottery 
clays as they contain will probably be found only in pockets. 
CLAY INDUSTRY. 
UTILIZATION OF THE CLAY SHALES. a 
Although the clay shales of Fort Smith and of Sebastian County 
are suitable for the manufacture of sewer pipe, fire bricks, and pot- 
tery, nothing has been done thus far to utilize these shales for making 
such articles. The abundance of excellent raw materials, the prox- 
imity of the deposits to the coal fields, and the possibility of building 
a The notes on the brick industries of Fort Smith are chiefly by William Kennedy. 
