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The former banks of the Mississippi rise abruptly above the flood- 
plain to heights of 250 feet in places and this elevation continues across 
the southern part of the state as a part of the Ozark highlands. There 
is a north and south axis parallel to the Mississippi culminating near the 
western part of the Jonesboro quadrangle in bluffs which rise to the 
height of 700 feet in the north, increase to 880 feet in the middle portion, 
and decrease again to 700 feet in the southern section. A detached fea- 
ture of these highlands rises like an island from the Mississippi plain at 
Fountain Bluff, but elsewhere they are continuous. The east and west 
axis ends in the chain of heights known as the Shawneetown hills, in 
Hardin county. 
The highest point of our area is some six miles east of the western 
bluffs at Bald Knob, Union county, where the north and south axis is 
intersected by the Ozark east and west axis, reaching a height of 1,025 
feet. Bald Knob, as already stated, is exceeded in height by Williams 
Mountain, in Pope county, and, again, by Charles Mound, in Jo Daviess 
county, but since Bald Knob overlooks the flat flood-plain of the Mis- 
sissippi, its actual relief is probably much greater than that of the other 
two points. 
Heavy erosion characterizes the western uplands, flanked as they are 
by the low Mississippi flood-plain. Innumerable short valleys with almost 
precipitous sides are found, separated by long, very narrow-topped ridges 
—a form of topography which does not readily lend itself to agriculture. 
This minutely dissected upland occurs in a strip averaging five to 
ten miles in width. East of it the stream valleys are wider, the slopes 
less precipitous, and the ridge-tops broader, so that the eastern section 
is well adapted to fruit-growing and general agriculture. In the north- 
eastern part, on the Big Muddy, and in the southeastern section, on the 
Cache River, wide flood-plains are found. 
DRAINAGE 
The northern and northwestern part of the region drains into Big 
Muddy River and its tributaries. Clear Creek, Dutch Creek, Harrison 
Creek, Horse Creek, and Sexton Creek break through the western bluffs 
into drainage ditches, emptying into the Mississippi River, while Mill 
Creek, Lingle Creek, Cooper Creek, and Sandy Creek, in the Jonesboro 
quadrangle, take their rise in the chert hills, and drain south or southeast 
into the Cache River. (See the Profiles sheet.) Geologists tell us that 
the Mississippi was at one time not the master stream, but that some of 
the streams now draining into it flowed south or southeast. 
While the rock strata have in general a slope towards the southeast or 
east, faults have somewhat broken up the continuity of this slope. The 
fact that there is such slope can be brought out by comparing elevations 
