the Arkansas, and the
mouth of the Mississippi river as extreme points; reaching from north
latitude 29 deg. to 42 deg., and without estimating mountains, ridges, or
peaks, differs in relative elevation at least 500 feet.

"The _Arkansas river_ rises near north latitude 42 deg., and longitude 32
deg. west from Washington, and falls into the Mississippi at 33 deg. 56',
passing over eight degrees of latitude.

"_Red River_ rises in the mountainous country of Mexico, north of Texas,
in north latitude 34 deg.; and west longitude 28 deg. from Washington,
and falls into the Mississippi in latitude 31 deg. They are both
remarkable rivers for their extent, the number of their branches, the
volume of their waters, the quantity of alluvion they carry down to the
parent stream, and the color of their waters. Impregnated by saline
particles, and colored with ocherous earth, the waters of these two
rivers are at once brackish and nauseous to the taste, particularly near
their mouths; that of Red river is so much so at Natchitoches at low
water that it cannot be used for culinary purposes.

"At a short distance below the mouth of the Red river, a large bayou,
(as it is called,) or outlet, breaks from the Mississippi on the west;
by which, it is believed, that as large a volume of water as the Red
river brings to the parent river, is drained off, and runs to the gulf
of Mexico, fifty miles from the mouth of the Mississippi. The name of
this bayou is Atchafalaya, or as it is commonly called, _Chaffalio_.
Below this bayou, another of large dimensions breaks forth on the same
side, and finally falls into the Atchafalaya. This is the Placquemine.
Still lower, at Donaldsonville, ninety miles above New Orleans, on the
same side, the Lafourche bayou breaks out, and pursues a course parallel
to the Mississippi, fifty miles west of the mouth of that river. On the
east side, the Ibberville bayou drains off a portion of the waters of
the Mississippi, into lakes Maurepas, Ponchartrain, Borgnes, and the
gulf of Mexico, and thus forms the long and narrow island of Orleans.

"In the lower Valley of the Mississippi there is a great extent of land
of the very richest kind. There is also much that is almost always
overflown with waters, and is a perpetual swamp. There are extensive
prairies in this Valley; and towards the Rocky mountains; on the upper
waters of the Arkansas and Red rivers, there are vast barren steppes or
plains of sand, dreary and