OUACHITA COUNTY. 139 
efflorescence of green vitriol (ferrous sulphate) derived from the 
clays. This green vitriol causes the peculiar taste of the water found 
in many of the wells at Camden. 
The character and disposition of the Tertiary beds at Camden 
may be taken in a certain sense as typical of the geology of Ouachita 
County. The strata there exposed extend beneath the whole county, 
but in a more or less modified form. This variability of the strata 
interrupts, of course, the continuity of the clay deposits and of what- 
ever else there may be of economic value in these beds. The sandy 
clays, for example, in their horizontal distribution give place to 
pottery clays, and pottery clays give place to brown coal, and brown 
coal gives place again to clays or sands or some of the other beds 
so common throughout the county. 
In some places the beds are deeply eroded and broad valleys are 
formed in them, so that the strata for several miles have been washed 
away, clays, sands, coals, a and all. The valley of the Ouachita is 
itself an example of such erosion. The road from Lester station, 
Parker Hill Seely Mountain 
Fig. 12.— Section of Parker ITill and Seely Mountain, Ouachita County. 
on the Camden branch of the St. Louis, Iron Mountain and Southern 
Railway, to Camden passes over a sharp ridge called Seely Moun- 
tain, which rises about 200 feet above the level of the Ouachita 
bottoms. About 4 miles northwest of Camden the same road ascends 
Parker Hill, which is geologically a repetition of Seely Mountain 
and which has the same elevation, the two being separated by a 
broad valley which has been cut out by the ordinary process of 
erosion. The profile section in fig. 12 will make plain the relations 
of these ridges to each other. 
These details of general structure are given for the purpose of 
showing how the distribution of clays in Ouachita County is deter- 
mined by the geology of the region. 
CLAY DEPOSITS. 
The region in which the brown coals occur is a promising one in 
which to seek valuable clays both for the manufacture of pottery 
and for fire clays. 
"The Geological Survey of the State has data for a report on the coals of Ouachita County, and the 
United States Geological Survey has published a report on this subject by Mr. Joseph A. Tallin Twenty- 
first Ann. kept , pt. 2, 1900, pp. 319-329. 
