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HYDKOGEAPHT. 
North Carolina lias gold, iron, marble, limestone, lead, " 
marl, and salt. 
Tennessee has compact limestone, marbles in great va- 
riety, saltpetre, Epsom salts, alum, fine quartzose sand for 
glass, hydraulic limestone, millstone grit, roofing slate, 
iron, zinc, lead, copper, coal in abundance, and gold and 
silver in small quantities. Marl is also found in the west- 
ern part of the State in the cretaceous system. 
South Carolina has marl, salt, metamorphic marble, gold. 
Georgia and Alabama have marl, salt, limestone, mar- 
ble, coal, gold, lead, and quartzose sand. 
Florida has no massive minerals, but has an abundance 
of clay, marl, and fine sand for glass. The same remark 
is applicable to Mississippi and Louisiana. There is no 
building limestone in any one of these three States, and 
the soft ferruginous sandstone is unfit for architectural pur- 
poses. Some salt has been found in Florida, and a con- 
siderable mine of it in Louisiana. 
Texas has marl, salt, coal, lead, saltpetre, and limestone. 
Arkansas has marl, salt, saltpetre, lead, silver, lime- 
stone and gold-bearing rocks, in which some gold has been 
found, roofing slate, and whetstone. 
SECT. II.— HYDROGKAPHY. 
We recognize in this region four w^ater slopes : 1. The 
Texas slope ; 2. The Mississippi slope ; 3. The eastern 
Gulf slope ; 4. The Atlantic slope. 
THE TEXAS SLOPE. 
Tlie largest rivers of this system are the Rio Grande, 
Nueces, San Antonio, Guadalupe, Colorado, Brazos, 
Trinity, Neches, and Sabine. 
