300 Bibliography. 
in the same manner at the Lookout Mountain, whence they extend to 
separating the Warrior coal field on the west from that of the Cahawba 
n the east; a in this direction they are confined to a series of con- 
tinuous valle They constitute a range of hills known as the “ Red 
bly enlarge this extent of Silurian beds e iron ore consists of 
. grains mostly flattened, like the lenticular argillaceous ore f New 
ork. In some places it passes into a conglomerate containing siliceous 
‘pebbles. A bed of brown hematite occurs on Shultz Creek, “also near 
‘the headwaters of Hurricane and Rockcastle Creeks twenty-four miles | 
. . from ‘Tuscaloosa, and at Bucksville. : 
. Heavy spar occurs in a vein a foot or two thick, near Pratt’s Ferry 
~~ on the Cahawba, and in another similar above Elyton. It is ground 
The carboniferous rocks cover all that part of the state above the 
lower falls of the riyers, not already described as belonging to the 
Red Mountain .group. The greatest development of the calcareous 
~ from which nitrate of potash is obtaine e coal measures eve 
- where rest“on. millstone grit. The mountains of Madison and Jackson 
~ counties andsiue bills of Morgan and Marshall counties are ‘often cap- 
’ ped with syndstones an and shales containing beds of coal. The Raccoon 
ead eowsnt rts ken have coal beds of considerable extent. These 
S <i the he Cabawba on the southwest contains about 150 square. miles. a 
te <. pahawba coal field i is bou nded on the south and east by the Little Ca- 3 
treat: { / a 
al sthonifercas rocks of De! 2 
Laren Saatice have not yo ea explored. The 
| hi 
en long in use in the 
' ee a ‘observations ¢ on ae eretaceous and ter- y 
vical” Trigonometry ; by Wasnt 
Unite es N 
