Mount Vernon (8,007), the county seat of Jefferson County, was the largest of the cities of the Big Muddy Basin in 1910. I t is an important railroad center.
Pinckneyville (2,722) is the county seat and Duquoin (5,454) the largest city in Perry County. Benton (2,675) is the county seat of Franklin County.
Murphysboro (7,486) is the county seat of Jackson County. Carbondale (6,411) is the scat of the Southern Illinois State Normal University.
Johnston City (3,248), Herrin (6,861), Carterville (2,971), and Marion (7,093) are in Williamson County, the most impor tant coal-producing county of the state, furnishing about one-sixth of the total for the state. These four cities have 45 per cent of the population of the county. Marion is the county seat.
Cities of the Saline Basin.—The Saline River and its tribu taries drain an area of considerable extent lying cast of the Big Muddy Basin and north of the Ozark Ridge. The Saline River empties into the Ohio about 15 miles below the mouth of the Wabash.
Harrisburg (5,309), county scat of Saline County, is the larg est city of the Saline Basin. Eldorado (3,366) is the second city of the county. Carrier Mills (1,558) at the foot of the Ozark Ridge has the southernmost coal mines of the state. The coal bearing rocks arc absent from the Ozarks. Saline County ranks high in coal production with twenty or more shipping mines.
Equality (1,180), in Gallatin County, was noted for its salt works in the days of early settlement in Illinois.
Shawneetown (1,863), county seat of Gallatin County, located on the Ohio River, six miles below the mouth of the Wabash, was the leading city of southeastern Illinois in the pioneer days when travel and commerce were largely carried on by river.
Cities of the Ozark region.—The Ozark Plateau and its spurs occupy the southernmost seven counties of Illinois. These seven counties have four cities with populations of 2,500 or more, only one of which is on the Ozark uplands, the other three being ports on the Ohio River.
Jonesboro (1,169) is the county seat of Union County. Anna (2,809) is the seat of a state hospital.
Vienna (1,124) is the county seat of Johnson County.
Golconda (1,088), the county seat of Pope County, is located on the Ohio River, and it is the terminus of a railroad branch line. Fluor spar from the mines of Rosiclare is here transferred from the river to the railroad.
Rosiclare (609), in 1 larch,' County, has the largest fluor-spar mines in the world. A railroad about one mile in length brings the fluor spar from the mines to the wharf, where it is loaded on boats and taken downstream to Golconda or up stream to Shawneetown for transshipment by railroad.
Elizabethtown (633), the county seat of Hardin is known everywhere throughout southern Illinois as E-town.
Thebes (717), in Alexander County, is at the Illinois end of a railroad bridge, the only Illinois bridge across the Missis sippi south of St. Louis.
Cairo (14,548), the county seat of Alexander County, is located at the junction of the Ohio and Mississippi rivers with its wharves on the Ohio River front. A railroad bridge crosses the Ohio River here. Cairo is the metropolis of southern Illinois. It is the largest city in Illinois south of Belle ville, 120 miles away. No city so large as Cairo is found to the north and east until we reach Springfield or Decatur, 200 miles to the north, or Danville, 250 miles to the northeast, in each case more than half the distance from Cairo to Chicago. Cairo has important commercial and manufac turing interests.
Mound City (2,837), the county seat of Pulaski County, is a river port on the Ohio, 7 miles upstream, almost due north from Cairo. It has important lumber industries. Mounds (1,686), 3 miles from Mound City, is an important railroad junction.
Joppa (734), in Massac County, is a river port, a railroad terminus, and an important center for truck farming for northern markets.
Metropolis (4,655), the county seat of Massac County, is an important river port, and the site of a new railroad bridge across the Ohio, the only one in Illinois above Cairo. The Fort Massac State Park, near which George Rogers Clark entered Illinois, is located at Metropolis. It contains a monu ment to George Rogers Clark.