The republic. [volume] (Washington [D.C.]) 1849-1853, 1849-07-18

mlNHSOIA-NOs ..
The topography and general geography of Nine
sofa cannot be well understood without giving full
prominence to the character, course and origin of
the Mississippi
Geologically considered, the Mississippi river
originates in the erratc block groupe or drift stra-
tum of the north, in longitude 1872 west OF Wash
lngon, and north latitude 47o ID 35', agreeably TO
Mr. Ncollet. This stratum develops itself IN
prominent range of sand-hills, once perhaps naked
ocean dunes, which throw out copions springs OF
the pures water on all sides. These infant sources
of the father of rivers" first gather themselves to-
gether in handsome lake, called lTAscA or La
Biche Of some seven miles in length, whose shores
are surrounded with deciduous trees-plnes being
in sight on the neighboring ridges, and having
beautiful island near its centre, rich with the foliage
of the elm, wild cherry, soft maple, and other
northern species. From this lake the Mississippi
sets on his wonderful course of more than 5000
miles to the gulf, by an outlet sixteen feet wide,
with depth of fourteen understanding body OF
pure crystal water, gliding rapidly over its sandy
and pebbly bed In which the traveller, as he shoots
| along in his canoe, can see the broken white and
pearly valves of the unto and other fresh-water
| shells of the lake scattered in its bed.
Thus much geographically. This great north
ern drift stratum, which constitutes the height of
land, rests on a broad range of the crystalline or
primary rocks, which cross the continent between
attitudes about Al to 500, linking together the
mountain groups Of the Labrador and Hudson's
bay coasts with the Rocky mountains. To these
broad ranges and mountain outbreaks as they are
developed, west Of James's bay and north of Lake
Superior, Bouchette, the geographer of Canada, has
| applied the name of CabotiGn mountains, in alusOn
| to the true dscoverer Of North America.
| Agreeabiy to this theory, the st. Louis river,
| which falls into the head of Lake Superior, pre-
senting series of magnificent views and cataracts,
passes transyersely through the Cabotian chain,
while the Rainy lakes and the Lake of the Woods
lie north Of it, This range Of transverse rocks
which, with all its diluval and drift covering, does
not rise over 600 feet above the ocean, may be sad
by Its rocky roots, to continue west from the ltasca
| highlands, and to divide the waters of the Upper
Missouri from those of the Saskatchiwine and
Assinaboin valleys of Red river and Lake Winni-
pee The natural line Of elevations denotes this.
II is, in fine, the transverse Wasserschied, wa
| ter-shed between the Hudson's bay and the st.
Lawrence waters and those of the Gulf of Mexico.
1t is impossible to visit this remote summit to
which the French apply the term Hataeur des Ierres,
and examine It's oceanic dunes, gravel beds, sand
plains, and other characteristic features, without
supposing the present condition of its surface to
be the result of ocean currents however produced,
which, at very ancient period of the globes his
tory, poured their waters over these heights, sur
charged with the ruins of broken strata and dis
rupted formations which once spread over the area
north of them. We observe, amidst the heavy beds
anu SldtcS, anu Vi pTl-
mary rocks from remoter positions, very widespread
evidences Of trap and greenstones, granwackes and
anygdalods, which tell of the prostration of voca-
mic formations, with all their peculiar imbedded
minerals and veinsones. Ofthese latter the harder
varieties of the quartz family with zoned agates and
less abundantly chacedonies and carnelians, are
found both in the dry drift, at the highest eleva-
tons, and about the shores of lakes and streams.
These masses have been carried, by fuvatile ac-
ton, down the Mississippi valley, to great dis
tances, suffering more and more from the force of
attrition. They often picked up, very well
characterized, on the shores of Lake Pepin. have
traced them as low as ST. Louis and Herculaneum.
1t is peculiar feature of the ltasca summit, and
Its various seppes, that it has sub-soi or deposit
of an alumlnous or impervious character resting
below the various sand plains, loans, and loose
carbonaceous and sphagnous beds This appears
to be the true cause of the retention, at those
heights, of vast body Of water in the shape of
lakes, which are of every imaginable size, from half
a mile TO thirty miles in length. 1t will not be too
much, perhaps, to say, that fifty thousand of these
lakes exist within borders, north of latitude 44o
These lakes in the drift stratum so remarkable for
their number, consist of transparent, most often
very pure water, the temperature of which is gene
rally 50 to 100 below that of the atmosphere.
wide Mar. Jour. Pub. Ex. of 1890, p. l66, &c }
They are supposed, in several districts, to have a
subterraneous communication with each other,
without visible outlets. The water that sustains
such system Of lakes and rivers is, manfestly, the
result of the condensed vapors of the ocean which
have been waited from warmer attitudes, and con-
densed on these broad eminences.
The lakes of the submountan region of Mine
sotse may all be considered falling under two
classes, those with clean sandy shores, and con-
siderable depth, and those whose margins consist of
a sphagnous character, and abound in the zizania
palustrs, or wild rice, and comparatively shall
low. The former yield various species Of fish.
The latter serve not only as store-house Of grain
for the natives, who gather it in August and Sep
TENDER, but they invite myriads Of waterfowl into
the region, and thus prove double resource to
them 1t is constantly affirmed, that fish taken
in lakes which have no visible outlet. Some of the
larger open lakes connected with the Mississippi
yield even the white fish, which is so celebrated in
the upper iakes-while in have fish of this
species ever been found in the Mississippi itself
ALGON.