State is traversed
with ranges of hills or mountains. At the verge of the alluvial soil on
the margins of rivers, there are ranges of "bluffs" intersected with
ravines. The bluffs are usually from fifty to one hundred and fifty feet
high, where an extended surface of table land commences, covered with
prairies and forests of various shapes and sizes.

When examined minutely, there are several varieties in the surface of
this State, which will be briefly specified and described.

1. _Inundated Lands._ I apply this term to all those portions, which,
for some part of the year, are under water. These include portions of
the river bottoms, and portions of the interior of large prairies, with
the lakes and ponds which, for half the year or more, are without water.
The term "bottom" is used throughout the West, to denote the alluvial
soil on the margin of rivers, usually called "intervales," in New
England. Portions of this description of land are flowed for a longer or
shorter period, when the rivers are full. Probably one eighth of the
bottom lands are of this description; for, though the water may not
stand for any length of time, it wholly prevents settlement and
cultivation, though it does not interrupt the growth of timber and
vegetation. These tracts are on the bottoms of the Wabash, Ohio,
Mississippi, Illinois, and all the interior rivers.

When the rivers rise above their ordinary height, the waters of the
smaller streams, which are backed up by the freshets of the former,
break over their banks, and cover all the low grounds. Here they stand
for a few days, or for many weeks, especially towards the bluffs; for it
is a striking fact in the geology of the western country, that all the
river bottoms are higher on the margins of the streams than at some
distance back. Whenever increase of population shall create a demand for
this species of soil, the most of it can be reclaimed at comparatively
small expense. Its fertility will be inexhaustible, and if the waters
from the rivers could be shut out by dykes or levees, the soil would be
perfectly dry. Most of the small lakes on the American bottom disappear
in the summer, and leave a deposit of vegetable matter undergoing
decomposition, or a luxuriant coat of weeds and grass.

As our prairies mostly lie between the streams that drain the country,
the interior of the large ones are usually level. Here are formed ponds
and lakes after the winter and spring rains, which rem