The oldest, bordering the Lower Carboniferous, is the Tuscaloosa formation of clays and sands arranged as follows: dark clays, thin lignite seams, lignitic clays, sands and chert, and light clays; this formation is 5-15 m.
Tuscaloosa clays are used in the manufacture of pottery.
Overlying the Tuscaloosa are the Eutaw sands, characterized by sandy laminated clays, and yellow, orange, red and blue sands, containing lignite and fossil resin.
In1824-1828he was professor of mathematics and natural philosophy at Brown University, acting as president in 1826-1827; in1828-1831was president of Transylvania University, Lexington, Kentucky; and in1831-1837was president of the University of Alabama at Tuscaloosa, where he organized the Alabama Female Athenaeum.
The Comanchean formations are found (I) on the inland border of the coastal plain of the Atlantic (Potomac series) and Gulf coasts (Tuscaloosa series at the east and Comanchean at the west); (2) along the western margin of the Great Plains and in the adjacent mountains; and (3) along the Pacific coast west of the Sierras.