office a mass of this red sand rock, of about twelve inches
diameter, perfectly round and ball-shaped, which he had directed
one of the soldiers to pick up, in an excursion among the islands
of the lower St. Mary's. This ball was a monument of that physical
throe which had originally carried this river through the sandstone
pass of St. Mary's, having been manifestly rounded in what geologists
have called "a pocket hole" in the rock at the falls, and afterwards
carried away, with the disrupted rocks, down the valley.
[220] The Indiana call it _Pauwateeg_ (water leaping on the rocks),
when speaking of the phenomenon, and _Pawating_, when referring to
the place of it.
RED SANDSTONE OF LAKE SUPERIOR.--That this is the old red sandstone, may
be inferred simply from the fact that, although deposited originally in
horizontal beds, its position has been disturbed in many localities.
PLASTIC CLAY STRATUM OF THE LAKES.--The northern extremity of Muddy
Lake--a sheet of water some twenty miles in length--is the head of the
straits, and the beginning of the River St. Mary's. This sheet of water
has the property of being rendered slightly whitish, or turbid, by
continuous winds. Its bottom appears to be formed of the same plastic
blue clay which obstructs the passage of vessels of large draft on the
St. Clair flats, and forms an impediment of a similar kind in this river
in Lake George. This stratum seems to be the result of causes not now in
operation. If dredged through, or excavated, there is no reason to
suppose it would again accumulate; for the waters of the lake are clear
and pure, and carry down no deposit of the kind. These clay deposits
remain to attest physical changes which are past. They denote the
demolition of formations of slate in the upper regions, which have been
broken down and washed away when the dominion of the waters was far more
potential than they now are.
This formation is favorable to the growth of some species of fresh-water
shells. I observed several species of the anadonta and the plenorbis,
and think, from the broken valves, that research would develop others.
PORPHYRY AND CONGLOMERATE BOULDERS.--A formation of red jasper, in
common white quartz, exists, in the bed of intersection, on the
southeastern foot of Sugar Island. The fragments of jasper are of a
bright vermil red, quite opaque, and have preserved their angles. I had
observed fragments of the formation along the shores of the lower part
of the straits, and even picked up some specimens, entirely abraded,
however, on the south shores of the Huron, between the White Rock and
Michilimackinac--a proof of the course of the drift.
The granitic conglomerates appear quite conclusive, one would think, of
the results of fusion. The attraction of aggregation would seem
inadequate to hold together such diverse masses. In these curious and
striking masses we see the red feldspathic granite, black and shining
hornblende rock, white fatty quartz, and striped jasper, held together
as firmly, and polished by attrition as completely, as if they
were--what they are not--the results of crystallization in this
aggregate form.
ERRATIC BLOCK GROUP.--Wherever, in fact, the geologist sets his foot, on
the shores of the upper lakes, he finds himself on the great drift
stratum, and cannot but revert to that era when waters, on a grander
scale, swept over these plains, and the lakes played rampantly over
wider areas.[221]
[221] During a subsequent residence of eleven years at this point,
the excavations made on both sides of the river, in digging wells,
canals made by the military, &c., fully demonstrated the truth of
this general observation. In these positions, it was evident that
some greatly superior force of watery removal, such as does not now
exist, had heaped together particles of similar matters, according to
laws which govern moving, compacted masses of water, leaving clay to
settle according to the laws of diffused clay, sand of sand, and
pebbles and boulders of pebbles and boulders. In their change and
redeposit, gravity has evidently been the primary cause, modified by
compressed currents, attraction, and probably those secret and still
undeveloped magnetic and electric influences which exist in
connection with astronomical phenomena. That the earth's surface,
"standing out of the water and in the water," has been disrupted and
preyed upon by oceanic power, no one, at this day of geological
illumination, will deny.
BASIN OF LAKE SUPERIOR.--We entered this island sea as if by a kind of
geological gate, in which the sandstone cliffs of Point Iroquois, on the
one hand, stand opposite to the granitical hills of Gross Cape on the
other.
In order to conceive of its geology, it may subserve the purposes of
description to compare it to a vast basonic crater. The rim of this
crater has been estimated, by Sir Alexander Mackenzie, at fifteen
hundred miles. The primitive formations of Labrador and Hudson's Bay
coasts come up, so as to form the eastern and northern sides of the rim,
around which they stand in cliffs of sienitic greenstone and hornblendic
rocks, in some places a thousand feet high. On its south and southwest
shores, this formation of the elder class of rocks forms also a
considerable portion of the coast; as in the rough tract of Granite
Point, the Porcupine and Iron River Mountains, and the primitive tract
west of Chegoimegon, or Lapointe. It will serve to denote the broken
character of this rim, if we state that the entire plain of the lake,
running against and fitting to this rim, was originally filled up with
the red, gray, and mottled sandstone, which gave way and fell in at
localities west of the great Keweena Peninsula, converting its bottom
into an anteclinal axis.
Volcanic action, to which this disturbance in its westerly bearings may
be attributed, appears to have thrown up the trap-rocks of the Pic, of
the Porcupine chain, of the Isle Royal group, and other trap islands,
and the long peninsula of Keweena. This system of forces appears to have
spent itself from the northeast to the southwest. The shocks brought
with them the elements of the copper and other metallic bodies which
characterize the trap-rock. They exhausted their power, on the American
side, west of the granitic tract of Chocolate and Dead Rivers, and the
Totosh and Cradle-Top Mountains. The most violent disturbance took place
at the west of the Keweena Peninsula, and thence it was propagated in
the direction of the higher Ontonagon, the Iron, and the Montreal
rivers.
This disturbance of the level of the sandstone produced undulations,
which are observable on the St. Mary's, where the variation from a level
is not more than eight or ten degrees. They left portions of it--as
between Isle au Train and the Firesteel River--undisturbed; and they
threw other portions of it--as between Iron and Montreal rivers--almost
completely on their edges.
The entire north shore from Gargontwa to the old Grand Portage,
inclusive of the Michepicotin and Pic regions, cannot be particularly
alluded to, as that part of the coast was not visited; but the accounts
of observers represent it as consisting of trap-rocks. Without the
application of such forces, it appears impossible to understand the
geology of this lake, or to account for the sectional and disturbed
formations.
The lake itself, whose depth is great, and which has an extreme length
of about 500 miles, by an extreme width of some 180, is endowed with
powerful means of existing elemental action. This consists almost
entirely of the force of its winds and long, sweeping waves. Its bottom
may, in this light, be looked upon as an immense mortar or triturating
apparatus, in which its sandstones, trap-boulders, and pebbles are
driven about and comminuted. This power has greatly changed its
configuration, and the process of these mutations is daily going on.
It is only by such a power of geological action that we can account for
the powerful demolitions and inroads which it has made upon some parts
of its southern borders. The coasts of the Pictured Rocks, which have a
prominent development of about 12 to 15 miles, consist in horizontal
strata of coarse gray sandstone, of little cohering power. The effect of
waves beating upon rocks is to communicate a curved line. This has
operated to excavate numerous and extensive caves into the coast. These,
after reaching hundreds of feet, have in some cases united. The effect
is to isolate portions of the coast, and to leave it in fearful
pinnacles, having many of the architectural characters of Gothic or
Doric ruins.
The portion of coast immediately west of Grand Marrais is scarcely less
unique. It denotes the effect of the prostrating power of the lake in
another way. The sandstone of parts of the coast, ground down into
yellow sand by this vast machinery, is lifted up by the winds as soon as
it reaches the point of dryness, and heaped up into vast dunes. Standing
trees are buried in these tempests of sand, and its effect is, for about
nine miles along the coast, to present, at an elevation of several
hundred feet, a scene of arid desolation, which can only be equalled by
the Arabic deserts.
A dyke of trap seems once to have extended from the north shore to Point
Keweena; but, if so, it has been prostrated, and its contents--veins and
deposits, silicious and metallic--scattered profusely around the shores
of the lakes. A cause less general is hardly sufficient to account for
the wide distribution of fragments of the copper veins and vein-stones
which have so long been noticed as characters of this lake. The basal
remains of this antique dyke form the peninsula of Keweena. The tempests
beating against this barrier from the northwest, have ripped up terrific
areas from the solid rock, and left its covering, amygdaloid and
rubblestones, in fantastic patches upon the more solid parts, or
constituting islands in front of them.
STRUCTURE OF ITS SOUTHERN COAST.--The estimated distance from Sault Ste.
Marie to Fond du Lac is a fraction over 500 miles. The sandstone, as it
appears in the Falls of the St. Mary's, does not appear to be entirely
level. It exhibits an undulation of about 8° or 10°, dipping to
west-northwest. Two instances of this waved stratification of the Lake
Superior sandstone deserve notice. The first terminates at the
intersection of red sand rock at la Point des Grande Sables with the
beginning of the horizontal strata of the Pictured Rocks. We again
observe an inclination of the strata of a few degrees at Grand Island,
which is moreingfish River, and appears to dip at Isle aux Trains,
about twenty miles northeast. The scenery is peculiarly soft and
pleasing in passing the Huron Islands, a granitic group, and directing
the view, as in the sketch, to the coast and the rough granitical hills
rising behind Huron Bay. The strata are level, as shown above, around
the Bay of Presque Isle and Granite Point, and continue so, resting on
the roots of the granitical tract of the _Tötosh_, or Schoolcraft, and
Cradletop Mountains, and at Point aux Beignes, and Keweena Bay. This
level position of the rock is preserved to the south cape of the shallow
bay of the Bete Gre, on the north, at which the trap-dykes of the
peninsula first begin; and so continues after passing that rugged coast
of the vitreous series of that remarkable point, to and beyond Eagle
River and Sandy Bay, in the approach to the portage of the Keweena.
The same horizontality is observed on the headland west of it, and upon
all the points and headlands to Misery and Firesteel Rivers and the
mouth of the Ontonagon. The trap-dyke of Keweena crosses this river
about ten miles, in a direct line, inland.
At Iron River, we observe a stratum of compact gray grauwacke, over the
hackly bed of which that river forces its way during the spring months,
and stands in tanks and pools during the summer. On reaching the foot of
the Porcupine Mountains, the sandstone, which is here of a dark
chocolate color, with quartz pebbles of the bigness of a pigeon's egg,
and organic remains of paleozoic type, is found to be tilted up into
nearly a vertical position, as shown in the sketch. The grauwacke
reappears, in a most striking manner, at the Falls of Presque Isle
River, where the whole mass of water precipitated from the highlands
drops into a vast pot-hole, a hundred feet wide and perhaps twice that
depth. The whole upper series of rocks, from the Porcupine Cliffs west
to the Montreal River, is a conglomerate. At the Falls of the Montreal,
the river drops over the vertical edges of the red sandstone. Beyond the
Bay of St. Chares, at Lapointe Chegoimigon, masses of sienitic mountains
arise, which have their apex near La Riviere de Fromboise.
The Islands of the Twelve Apostles, or Federation Group, appear to be
all based on the sienitic or trap, with overlying red sandstone; which
latter again reappears on the point of the entrance into Fond du Lac
Bay, and marks its southern coast, till near the entrance of the Brulé,
or Misakoda River, as seen in the illustration beneath. Shores of sand
then intercept its view to the entrance of the River St. Louis, and up
its channel to its first rapids, about eighteen miles, where the red
sandstone again appears, as the first series of the Cabotian Mountains.
SERPENTINE ROCK.--At the nearest point north of Rivier du Mort is a
headland of this rock, jutting out from the granitical formation.
Lapping against it, at the mouth of the river, is a curious formation of
magnesian breccia. The serpentine rock appears, in nearly every locality
examined, to be highly charged with particles of chromate of iron. It
may be expected to yield the usual magnesian minerals.[222] Its position
is between the Carp River and Granite Point, in the Bay of Presque Isle,
or rather Chocolate River, for that river pours into this bay by far the
largest quantity of water.[223]
[222] In 1831, in making some explorations of this rock with
gunpowder, I found the serpentine in a crystalline state, of a
beautiful deep-green color, but appearing as if the crystallization
was pseudomorphous.
[223] The extensive iron mines of Marquette County, Upper Michigan,
are now worked in this vicinity.
ANCIENT DRIFT-STRATUM.--In the intervals between the points and
headlands, where the rock formation is exposed by streams or gorges, the
drift, or erratic boulder stratum, is found. Such is its position
beneath the sand-dunes of the Grandes Sables, and in the elder plains
and uplands, stretching with interruptions on the coast from the head of
the Mary's valley to that of the St. Louis. The edge of this formation
is composed of the sand and loose pebbles and boulders of the lake.
Mighty as are the existing causes of action of the lake in beating down
and disrupting strata of every kind, and in reproducing alluvial lands
and dunes, they are weak and local when compared to the causes which
have spread these ponderous boulders, and drift masses over latitudes
and longitudes which appear to be limited only by the leading elevations
of the continent. That oceanic torrents of water, suddenly heaped on the
land, and wedged into compactness and power now unknown to it, is after
all, the most plausible theory of the dispersion of this formation, and
this theory avoids the necessary local one of the glacial dispersion
which presupposes a very low temperature over the whole surface of the
globe.
KAUGWUDJU.[224]--This imposing mass of the trap-rocks is the highest on
the southern shores of Lake Superior. The following outlines of it are
taken from a point on the approach to the Ontonagon River, about forty
miles distant.
[224] Porcupine Mountains. From _kaug_, a porcupine, and _wudju_,
mountain.
They rise to their apex about thirty miles west of that stream, in north
lat. 46° 52´ 2´´, as observed by Captain Douglass. They are distant
three hundred and fifty miles from St. Mary's. In a serene day they
present a lofty outline, and were seen by us from the east, at the
distance of about eighty miles. The Indians represent them to have a
deep tarn, with very imposing perpendicular walls, at one of the highest
points. If Lake Superior be estimated at six hundred and forty feet
above the Atlantic, as my notes indicate, its peaks are higher than any
estimates we have of the source of the Mississippi, and are, at least,
the highest elevations on this part of the continent. The granitical
tract of the St. Francis, Missouri,[225] and of the quartz high lands of
Wachita, Arkansas, the only two known primitive elevations between the
Rocky and Alleghany chains, are far less elevated.
[225] _Vide_ my view of the lead mines, in the Appendix to "Scenes
and Adventures in the Ozark Mountains."
I have now taken a rapid glance at the formations along the southern
shore of the lake between St. Mary's and Fond du Lac; but have passed by
some features which may be thought to merit attention.
EXISTING LAKE DRIFT.--The gleaner among the rock debris of this lake has
a field of labor which is not dissimilar to that of the fossilist. If he
has not, so to say, to put joint to joint, to establish his conclusions,
he has a mineralogical adjustment to make every way as obscure. A
boulder of sienite, or a mass of sandstone, or grauwacke, may be easily
referred to a contiguous rock. But when the observer meets with species
which are apparently foreign to the region, he is placed in a dilemma
between the toil of an impossible scrutiny and the danger of an
unlicensed conjecture.
Among the more common masses which may be assigned a locality within the
compass of the lake, are granites, sienites, hornblendes, greenstones,
schists, traps, grauwackes, sandstones, porphyries, quartz rocks,
serpentines, breccias, amygdaloids, amphiboles, and a variety of masses
in which epidote and hornblende are essential constituents. With these,
the coast mineralogist must associate, in place or out of place, agates,
chalcedonies, carnelians, zeolite, prehnite, calcareous spar,
crystalline quartz, amethystine quartz, coarse jaspers, noble
serpentine, iron-sand, iron-glance, sulphate of lead, chromate of iron,
native copper, carbonate of copper, and various species of pyrites.
These were, at least, my principal rewards for about eighteen days'
labor, in scrutinizing, at every possible point, its lengthened and
varied coasts.
CUPREOUS FORMATION.--The whole region, above Grand Island at least,
appears to have been the theatre of trap-dykes, and an extensive action
from beneath, which brought to the surface the elements of the formation
of copper veins. These have not been much explored; but, so far as
observation goes, there are evidences which cannot be resisted, that the
region contains this metal in various shapes and great abundance. I
refer to my report of the 6th of November, 1820, for evidences of a
valuable deposit of this metal in the valley of the Ontonagon River, and
at other points. I found the metal in its native state at various other
localities, and always under physical evidences which denoted its
existence, in the geological column of the lake, in quantity. These
indications were confined almost exclusively to the area intervening
between the peninsula of Keweena, and La Pointe Chegoimegon, a distance
of about one hundred and fifty miles. Of this district, the two
extremities would make the Ontonagon Valley about the centre.[226] A
profile of one of the detached pieces, found in the Ontonagon Valley,
and forwarded to you by Mr. Van Rensselaer, is herewith given.
[226] I would also refer, for subsequent information, to my report of
the 1st of October, 1822, made in compliance to a resolution of the
Senate, and printed in the Executive Documents of that year, No. 365,
17th Congress, 2d session.
VITRIC BOULDERS.--Among the debris of Lake Superior are masses of
trachyte, and also small pieces of the sienitic series, in which the red
feldspar has a calcined appearance, the quartz being, at the same time,
converted into a perfectly vitreous texture. Similar productions, but
not of the same exact character, exist on the sandy summits of the
Grande Sable. These exhibit an exterior of glistening cells or
orifices: it may be possible that they have been produced by fusion; but
I think not. The smooth cells appear like grains of sand hurled by the
winds over these bleak dunes. I have brought from that locality a single
specimen of pitchstone, perfectly resinous, bleak and shining.
LA POINTE CHEGOIMEGON.--A sketch of these islands, as given in the
Narrative, denotes that their number is greatly underrated, and will
serve to show the configuration of a very marked part of the Superior
coast. It must, hereafter, become one of the principal harbors and
anchoring-ground for vessels of the lake.
VALLEY OF THE ST. LOUIS RIVER.--The St. Louis River takes its rise on
the southern side of the Hauteur des Terres, being the same formation of
the drift and erratic block stratum which gives origin, at a more
westerly point, to the Mississippi. Its tributaries lie northwest of the
Rainy Lakes. Vermilion Lake, a well-known point of Indian trade, is a
tributary to its volume, which is large, and its outlet rushes with a
great impetus to the lake. At what height its sources lie above Lake
Superior, we can only conjecture. It was estimated to have a fall of two
hundred and nine feet to the head of the Portage aux Coteaux, and may
have a similar rise above.
By far its most distinguishing feature is its passage at the Grand
Portage through the Cabotian Mountains. We entered it at Fond du Lac and
pursued up its channel through alluvial grounds, in which it winds with
a deep channel about nineteen or twenty miles to the foot of its first
rapids. This point was found one mile above the station of the American
Fur Company's trading-house. Here we encountered the first rock stratum,
in the shape of our old geological acquaintance, the old red sandstone
of Lake Superior. It was succeeded in the first sixteen miles, in the
course of which the river is estimated to fall two hundred feet--most of
it in the first twenty-nine miles--by trap, argillite, and grauwacke.
Through these barriers the water forces its way, producing a series of
rapids and falls which the observer often beholds with amazement. The
river is continually in a foam for nine miles, and the wonder is that
such a furious and heavy volume of water should not have prostrated
everything before it. The sandstone, grauwacke, and the argillite, the
latter of which stands on its edges, have opposed but a feeble barrier;
but the trap species, resisting with the firmness, as it has the color
of cast-iron, stand in masses which threaten the life and safety of
everything which may be hurled against them. I found a loose specimen of
sulphuret of lead and some common quartz in place in the slate rock, a
vein of clorite slate, and a locality of coarse graphite, to reward my
search.
The Portage aux Coteaux, which is over the basetting edges of the
argillite, will give a lively idea of the effects of this rock upon the
feet of the loaded voyageurs.
The sandstone is last seen near the Galley on the Nine Mile Portage.
Above the Knife Portage, some eight miles higher, vast black boulders of
hornblendic and basaltic blocks, are more frequent; and these masses are
observed to be more angular in their shapes than the boulders and blocks
of kindred character encountered on the shores of Lakes Superior and
Huron. There is a vast sphagnous formation, which spreads westwardly
from the head of the Coteau Portage, and gives rise to the remote
tributaries of Milles lac and Rum River. Much of this consists of what
the Indians term _muskeeg_, or elastic bog. Hurricanes and tempests have
made fearful inroads upon areas of its timber, and it is seldom crossed,
even by the Indians. This tract lies east of the summit of sand-hills
and drift, which environ Sandy Lake, the _Komtaguma_ of the Chippewas.
The portage of the Savanna River, a tributary of the St. Louis, is the
route pursued by persons with canoes; there is no other species of water
craft adapted to this navigation. But wherever crossed, this swamp-land
tract imposes labor and toil which are of no ordinary cast. It is the
equivalent of the argillite which has been broken down and
disintegrated, forming beds of clay soil which are impervious to the
water, and we way regard this ancient slate formation of the true source
of the St. Lawrence tributaries, as the remote origin of those extensive
beds of an argillaceous kind, which exist at many places in the lower
lakes and plains.
Immediately west of the Savanna Portage, the Komtaguma summit is
reached. This summit consists wholly of arid pebble and boulder drift of
the elder period. It exhibits evidences of broken-down amygdaloids,
which not only furnish a part of its pebbles, but also of the contents
of this stratum, in numerous agates and other subspecies of the quartz
family which are found scattered over the surface. This is, in fact, the
origin of that extensive diffusion of these species, which is found in
the valley of the Upper Mississippi, as at Lake Pepin, &c., and which
has even been traced, in small pieces, as low as St. Louis and
Herculaneum in Missouri.[227] We may conclude that the ancient
sandstones, slates, and rubblestone, and amygdaloids, of which traces
still remain, were swept from the summit of the Mississippi by those
ancient floods which appear to have diffused the boulder drift from the
North.
[227] _Vide_ View of the lead mines.
SANDY LAKE.--The first view of this body of water was obtained from one
of those eminences situated at the influx of the west Savanna River.
This lake is bounded, on its western borders, by the delta of the
Mississippi; its outlet is about two miles in length. We here first
beheld the object of our search. The soil on its banks is of the richest
alluvial character. From this point, dense forests and a moderately
elevated soil, varying from three or four to fifteen feet, confined the
view, on either side, during more than two days' march. On the third day
after leaving Sandy Lake, at an early hour, we reached the Falls of
Pakágama. Here the rock strata show themselves for the first time on the
Mississippi, in a prominent ledge of quartz rock of a gray color.
Through this formation the Mississippi, here narrowed to less than half
its width, forces a passage. The fall of its level in about fifty rods
may be sixteen or eighteen feet. There is no cascade or leap, properly
so called, but a foaming channel of extraordinary velocity, which it is
alike impossible to ascend or descend with any species of water craft.
It lies in the shape of an elbow. We made the portage on the north side.
PAKÁGAMA SUMMIT.--The observer, when he has surmounted the summit,
immediately enters on a theatre of savannas, level to the eye, and
elevated but little above the water. Vistas of grass, reeds, and aquatic
plants spread in every direction. On these grassy plains the river winds
about, doubling and redoubling on itself, and increasing its cord of
distance in a ratio which, by the most moderate computation, would seem
extravagant. On those plateaux, and the small rivers and lakes
connected with them, the wild rice reaches the highest state of
perfection.
Our men toiled with their paddles till the third day, through this
unparalleled maze of water and plants, when we reached the summit of the
Upper Red Cedar or Cass Lake, where we encamped. In this distance no
rock strata appeared, nor any formation other than a jutting ridge of
sand, or an alluvial plain. Plateau on plateau had, indeed, carried us
from one level or basin to another, like a pair of steps, till we had
reached our extreme height.
CASS LAKE BASIN.--From estimates made, this lake is shown to lie at
thirteen hundred and thirty feet above the Atlantic.[228] This is a
small elevation, when we consider it as lying on the southern flank of
the transverse formation which forms the connecting link with the Rocky
Mountains. A rise or a subsidence of this part of the continent to this
amount, would throw the Hudson's Bay and Arctic waters down the
Mississippi valley. The scenery of its coasts is in part arenaceous
plains, and in part arable land, yielding corn to the Indians.
[228] Agreeable to barometric observations made in 1836, by Mr.
Nicollet, its true altitude is found to be 1,402 feet above the Gulf
of Mexico. Its latitude, by the same authority, is 47° 25´ 23´´.
SOURCES OF THE MISSISSIPPI.--In order to understand the geology of this
region, it is necessary to premise, that the St. Lawrence, the Hudson's
Bay, and the Mexican Gulf waters are separated by a ridge or watershed
of diluvial hills, called the Hauteur des Terres, which begins
immediately west of the basin of the Rainy Lakes and Rainy Lake River.
This high ground subtends the utmost sources of the Mississippi, and
reaches to the summit of Ottertail Lake, where it divides the
tributaries of the Red River of Lake Winnepec from those of the Des
Corbeau, or Great Crow-Wing River.
Within this basin, which circumscribes a sweep of several hundred miles,
there appears to have been deposited, upon the trap and primary rocks
which form its nucleus, a sedimentary argillaceous deposit, capable of
containing water. Upon this, the sand and pebble drift reposes in strata
of unequal thickness, and the sand is often developed in ridges and
plains, bearing species of the pine. The effect has been, that the
immense amount of vapor condensed upon these summits, and falling in
dews, rains, and snows, being arrested by the impervious subsoil of
clay, has concentrated itself in innumerable lakes, of all imaginable
forms, from half a mile to thirty miles long. These are connected by a
network of rivers, which pour their redundancy into the Mississippi, and
keep up a circulation over the whole vast area. The sand plains often
resting around the shores of these lakes create the impression of bodies
of water resting on sand, which is a fallacy. Some of these bodies of
water are choked up, or not well drained, and overflow their borders,
forming sphagnous tracts. Hence the frequent succession of arid sand
plains, impassable muskeegs, and arable areas on the same plateaux.
Every system of the latter, of the same altitude, constitutes a plateau.
The highest of these is the absolute source of the Mississippi waters.
The next descending series forms another plateau, and so on, till the
river finally plunges over St. Anthony's Falls.
In this descending series of plateaux, the Cass, Leech Lake, and Little
Lake Winnipec form the third and fourth levels.
In descending the Mississippi below the Pakágama, the first stratum of
rock, which rises through the delta of the river, occurs between the
mouth of the Nokasippi and Elm Rivers, below the influx of the Great De
Corbeau. This rock, which is greenstone trap, rises conspicuously in the
bed of the stream, in a rocky isle seated in the rapid called--I know
not with what propriety--the BIG FALLS, or _Grande Chute_. The
precipitous and angular falls of this striking object decide that the
bed of the stream is at this point on the igneous granitical and
greenstone series. This formation is seen at a few points above the
water, until we pass some bold and striking eminences of shining and
highly crystalline hornblendic sienite, which rises in the elevation
called by us Peace Rock, on the left bank, near the Osaukis Rapids. This
rock lies directly opposite to the principal encampment on the 27th of
July, which was on an elevated prairie on the west bank. To this point a
delegation of Sioux had ascended on an embassy of peace from Fort
Snelling to the Chippewas, having affixed on a pole what the exploring
party called a bark letter, the ideas being represented symbolically by
a species of picture writing, or hieroglyphics. In allusion to this
embassy, this locality was called the Peace Rock. This rock is sienite.
It is highly crystalline, and extends several miles. Its position must
be, from the best accounts, in north latitude about 44° 30´. From this
point to Rum River, a distance of seventy miles, no other point of the
intrusion of this formation above the prairie soil was observed.
INTRODUCTION OF THE PALÆONTOLOGICAL ROCKS.--After passing some fifty
miles below this locality there are evidences that the river, in its
progress south, has now reached the vicinity of the great carboniferous
and metalliferous formations, which, for so great a length, and in so
striking a manner, characterize both banks of the Mississippi below St.
Anthony's Falls. About nine or ten miles before reaching these Falls,
this change of geological character is developed; and on reaching the
Falls the river is found to be precipitated, at one leap, over strata of
white sandstone, overlaid by the metalliferous limestone. The channel is
divided by an island, and drops in single sheets, about sixteen to
eighteen feet, exclusive of the swift water above the brink, or of the
rapids for several hundred yards below. This sandstone is composed of
grains of pure and nearly limpid quartz, held together by the cohesion
of aggregation. If my observations were well taken it embraces,
sparingly, orbicular masses of hornblende. It is horizontal, and
constitutes, in some places, walls of stratification, which are
remarkable for their whiteness and purity. This sandstone is overlaid by
the cliff limestone, the same in character, which assumes at some points
a silicious, and at others, a magnesian character. It is manifestly the
same great metalliferous rock which accompanies the lead ore of Missouri
and mines of Peosta or Dubuque. There rests upon it the elder drift
stratum of boulders, pebble, and loam, which marks the entire valley.
This latter embraces boulders of quartz and hornblende rock, along with
limestones and sandstones. It is overlaid by about eighteen inches of
black alluvial carbonaceous mould.
From St. Anthony's Falls the river is perpetually walled on either side
with those high and picturesque cliffs which give it so imposing and
varied an appearance, and its current flows on with a majesty which
seems to the imagination to make it rejoice in its might, confident of a
power which will enable it to reach and carry its name to the ocean in
its unchanged integrity.
ST. PETER'S RIVER AND VALLEY.--The importance, fertility, and value of
this tributary have particularly impressed every member of the party.
Its position as the central point of the Sioux power, and its border
position to the Chippewas, the representative tribe of the great
Algonquin family, render it now a place of note, which fully justifies
the policy of the department in establishing a military post at the
confluence of the river; and the importance cannot soon pass away, in
the progress of the settlement of the Mississippi Valley.[229] It is the
great route of communication with the valley of the Red River of the
North, and the agricultural and trading settlements of Lord Selkirk in
that fertile valley, and its complete exploration by a public officer is
desirable, if not demanded.[230]
[229] Thirty years has made it the centre of the new territory of
Minnesota, which has now entered on the career of nations.
[230] This object was accomplished by an expedition by Major L. Long,
in 1823.
Of its geological character but little is known, and that connects it
with both the great formations which have been noticed as succeeding
each other at the great Peace Rock. That the granitical formation
reaches it at a high point is probable, from the large reported
boulders. The Indians bring from the blue earth fork of it, one of their
most esteemed green and blue argillaceous pigments, of which the
coloring matter appears to be carbonate of copper. They also bring from
the Coteau des Prairie, probably Carver's "shining mountains," specimens
of that fine and beautiful red pipe stone, which has so long been known
to be used by them for that purpose. This mineral is fissile, and
moderately hard, which renders it fit for their peculiar ripe
sculptures. I found small masses of native copper in the drift stratum
at the mouth of this stream, on the top of the cliffs on the
Mississippi, opposite the mouth of the St. Peter's.
CRYSTALLINE SAND ROCK.--This stratum reveals the same crystalline
structure which is so remarkable in the sandstone caves, near the Potosi
road, in the county of St. Genevieve, Missouri; and the sand obtained
from it, like that mineral, would probably fuse, with alkali, in a
moderate heat, and constitute an excellent material for the manufacture
of glass. It is also, like the Missouri sandstone, cavernous. In both
situations, these caves appear to be due to water escaping through
fissures of the rock, where its cohesion is feeble, carrying it away
grain by grain.
In stopping at one of these caves, about twelve miles below St. Peter's,
we found this cause of structure verified by a lively spring and pond of
limpid water flowing out of it.
VALLEY OF THE ST. CROIX.--This river originates in an elevated range of
the elder sand and pebble drift, which lies on the summit between the
Mississippi system of formations, and the Lake Superior basin. It
communicates with the Brulé, which is "Goddard's River" of Carver, and
with the Mauvaise or Bad River of that basin. Specimens of native copper
have been found on Snake River, one of its tributaries.[231]
[231] This river was explored by me in 1831 and 1832, in two separate
expeditions in the public service, accounts of which have been
published in 1831 and 1832, of which abstracts are given in the
preceding pages.
GEOLOGICAL MONUMENTS.--In descending the river for the distance of about
one hundred miles below St. Anthony's Falls, my attention was arrested,
on visiting the high grounds, by a species of natural monuments, which
appear as if made by human hands seen at a distance, but appear to be
the results of the degradation and wasting away, on the Huttonian
theory, of all but these, probably harder, portions of the strata.
LAKE PEPIN.--This sheet commends itself to notice by its extent and
picturesque features. It is an expansion of the river, about twenty-four
miles long, and two or three wide. Both its borders and bed reveal the
drift stratum, and the observer recognizes here, boulders of the
peculiar stratification which has, in ancient periods, characterized the
high plateaux about the sources of the river. Such are its hornblendic,
sienite, quartz, trap, and amygdaloid pebbles, and that variety of the
quartz family which assumes the form of the agate and other kindred
species. Moved as these materials are annually, lower and lower, by the
impetus of the stream, other supplies, it may be inferred, are still
furnished by the shifting sand and gravel bars from above. The mass must
submit to considerable abrasion by this change, and the diminished size
of the drifted masses become a sort of measure of the distance at which
they are found from their parent beds.
CHIPPEWA RIVER.--This stream is the first to bring in a vast mass of
moving sand. Its volume of water is large, which it gathers from the
high diluvial plains that spread southwest of the Porcupine Mountains,
and about the sources of the Wisconsin, the Montreal, and the St. Croix
Rivers, with which it originates.
TROMPELDO (_Le Montaine des Tromps d'Eaux_).--This island mountain
stands as if to dispute the passage of the Mississippi, whose channel it
divides into two portions. Distinct from its height, which appears to
correspond with the contiguous cliffs, and in the large amount of fresh
debris at its base, it presents nothing peculiar in its geology.
PAINTED ROCK.--This vicinity is chiefly noted for its large and fine
specimens of fresh-water shells.
WISCONSIN.--Like the Chippewa, this stream brings down in its floods,
vast quantities of loose sand, which tend to the formation of bars and
temporary islands. It originates in the same elevated plains, and
bespeaks a considerable area at its sources, which must be arid. It is a
region, however, in which lakes and rice lands abound, and it may, in
this respect, be geologically of the same formation as the higher
plateaux of the Mississippi, above the Sandy Lake summit. Its sides
produce many species to enrich our fresh-water Conchology.
LEAD MINES OF PEOSTA AND DUBUQUE.--In my researches into the mineral
geography of Missouri, in 1818 and 1819, I had explored a district of
country between the rivers Merrimak and St. Francis, and on the Ozarks,
which revealed many traits which it has in common with the Upper
Mississippi. There, as here, the mineral deposits appear to be, in many
cases, in a red marly clay, whether the clay is overlaid by the
calcareous rock or not. There, as here, also, the limestone and
sandstone strata are perfectly horizontal. The leads of ore appear, in
this section, to be followed with more certainty, agreeable to the
points of the compass; but this may happen, to some extent, because the
practice of mining on individual account, with windlass and buckets, in
the Missouri district, has led common observers to be more indifferent
to exact scientific methods. To say that the digging, at these mines, is
equally, or more productive, is perhaps just. Capital and labor have
been rewarded in both sections of the country, in proportion as they
have been perseveringly and judiciously expended.
I found much of the ore, which is a sulphuret, at Dubuque's Mines, lying
in east and west leads. These leads were generally pursued in caves,
or, more properly, fissures in the rock. In one of the excavations which
I visited, the digging was continued horizontally under the first
stratum of rock, after an excavation had been made perpendicularly,
through the top soil and calcareous rock, perhaps thirty feet. The ore
is a broad-grained cubical galena, easily reduced, and bids fair very
greatly to enhance the value and resources of this section of the West.
Similar mines exist at Mississinawa, and the River Au Fevé,[232] both on
the eastern or left bank of the Mississippi. And a system of leasing or
management, such as I have suggested for the Missouri mines, appears
equally desirable.
[232] GALENA has subsequently been made the capital of these mines.
QUARTZ GEODES.--The amount of silex in the cliff limestone is such, in
some conditions of it, as to justify the term silico-calcareous. This
condition of the rock at the passage of the Mississippi through the Rock
River and Des Moines Rapids, is such as to produce a very striking
locality of highly crystalline quartz geodes, which accumulates in the
bed of the stream. Many of these geodes are from a foot to twenty-two
inches in diameter, and on breaking them they exhibit resplendent
crystals of limpid quartz. Sometimes these are amethystine; in other
cases they present surfaces of chalcedony or cacholong. The latter
minerals, if obtained from the rock, and before unduly hardening by
exposure, would probably furnish a suitable basis for lapidaries.
INTERMEDIATE COUNTRY IN THE DIRECTION TO GREEN BAY.--There is a line
which separates, on the north, the granitical and trap region from the
metal-bearing limestone, and its supporting sandstone. This formation of
the elder series of rocks, having been traced to the south shore of Lake
Superior, and having been seen to constitute the supporting bed of the
alluviums and diluviums of the Upper Mississippi, above the Peace Rock,
it may subserve the purpose of inquiry to trace this line of junction by
its probable and observed boundaries.
The line may be commenced where it crosses the Mississippi, at the Peace
Rock, and extended to the St. Croix, the falls of which are on the
trap-rock, to the sources of the Chippewa at Lac du Flambeau, and the
Wisconsin near Plover Portage. The source of Fox River runs amid
uprising masses of sienite, and this formation appears to pass thence
northeasterly, across the Upper Menominee, to the district of the
Totosh and Cradle-Top Mountains, west of Chocolate River, on the shores
of Lake Superior.
I observed the crystalline sandstone and its overlying cliff limestone,
along the valley of the Wisconsin, where ancient excavations for lead
ore have been made. There is an entire preservation of its characters,
and no reason occurs why its mineralogical contents should not prove, in
some positions, as valuable as they have been found in Missouri, or in
the Dubuque district west of the Mississippi.
On reaching the Wisconsin Portage, the limestone is found to have been
swept by diluvial action, from its supporting sand rock. Such is its
position not far north of the highest of the four lakes, and again at
Lake Puckway, in descending the Fox River; consequently, there are no
lead discoveries in this region. On coming to the calcareous rock, which
is developed along the channel of the river, below Winnebago Lake, it
appears rather to belong to the lake system of deposits. Its superior
stratum lies in patches, or limited districts, which appear to have been
left by drift action. Petrefactions are found in these districts, and
the character of the rock is dark, compact, or shelly. The lower series
of deposits, such as they appear at the Kakala Rapids, at Washington
Harbor, in the entrance to Green Bay, and in the cliffs north of
Sturgeon Bay and Portage, are manifestly of the same age and general
character as the inferior stratum of Michilimackinac and the Manatouline
chain.
BASIN OF LAKE MICHIGAN.--This basin, stretching from the north to the
south nearly four hundred miles, lies deeply in the series of formation
of limestones, sandstone, and schists, to which we apply the term of the
Michilimackinac system. Its north and west shores are skirted from Green
Bay to a point north of the Sheboygan, with the calcareous stratum. At
this point, the ancient drift, the lacustrine clay of Milwaukie and the
prairie diluvium of Chicago, constitute a succession, of which the
surface is a slightly waving line of the most fertile soils.
Among the pebbles cast ashore at the southern head of this lake I
observed slaty coal. It seems, indeed, the only one of the lakes which
reaches south into the coal basin of Illinois. If the level at which
coal is found on the Illinois were followed through, it would issue in
the basin of the lake below low-water mark. Digging for this mineral on
the Chicago summit, promises indeed not to be unsupported by sound
hypothesis.
After passing Chicago, of which a sketch is added, the sands which begin
to accumulate at the Konamik, the River du Chemin, and the St. Joseph's
River,[233] appear in still more prominent ridges, skirting the eastern
coasts to and beyond Grand River. These sands, which are the
accumulations of winds, are cast on the arable land, much in the manner
that has been noticed at the Grand Sable on Lake Superior, and reach the
character of striking dunes at the coast denominated the Sleeping Bear.
The winds which periodically set from the western shore, produce
continual abrasions of its softer materials, and are the sole cause of
these intrusive sand-hills. Pent up behind them, the water is a cause of
malaria to local districts of country, and many of the small rivers upon
this side are periodically choked with sand. The sketch transmitted of
this bleak dune-coast (omitted here), as it is seen at the mouth of
Maskigon Lake, will convey a false idea of the value of this coast, even
half a mile from the spot where the surf beats. It is designed to show
the air of aridity which the mere coast line presents. The
stratification regains its ordinary level and appearance before reaching
the Plate or Omicomico River, and the peninsula of the Grand Traverse
Bay, and the settlements of the Ottawa Indians on Little Traverse Bay,
afford tracts of fertile lands. Point Wagonshonce consists of a stratum
of limestone of little elevation, which constitutes the southeast cape
of the strait. Here a lighthouse is needed to direct the mariner.
[233] The subjoined petrifaction of a leaf, apparently a species of
betula, was obtained on this river. See _ante_, p. 206.
LAKE HURON.--Notices of this sheet of water have been given in our
outward voyage. It appears rather as the junction of separate lakes
which have had their basins fretted into one another, than as one
original lake. Michigan is connected with it through the Straits of
Michilimackinac. The Georgian Bay, north of the Manatouline chain, seems
quite distinct. The Saganaw Bay is an element of another kind. The
Manitouline chain separates the calcareous and granitic region, and its
numerous trap and basaltic islands towards the north shore, of which
there are many thousands, denote that it has been the scene of
geological disturbance of an extraordinary kind.
ULTERIOR CONCLUSIONS.--In taking these several views of the geological
structure of the Northwest--of the Lake Superior basin, and of the
valleys of the St. Louis River--the region about the Upper Mississippi,
its striking change at the Falls of St. Anthony--and the valleys of the
Wisconsin and Fox Rivers, and the basins of Lakes Michigan and Huron, I
am aware of the temerity of my task. Allowance must, however, be made
for the rapidity of my transit over regions where the question was often
the safety and personal subsistence of the party. A very large and
diversified area was passed over in a short time. At no place was it
possible to make elaborate observations. A thousand inconveniences were
felt, but they were felt as the pressure of so many small causes
impeding the execution of a great enterprise. A sketch has been made,
which, it is hoped, will reveal something of the physical history and
lineaments of the country. These glimpses at wild scenes, heretofore hid
from the curious eye of man, have been made, at all points, with the
utmost avidity. I have courted every opportunity to accumulate facts,
and I owe much to the distinguished civilian who has led the party so
successfully through scenes of toil and danger, not always unexpected,
but always met in a calm, bold, and proper spirit, which has served to
inspire confidence in all; to him, and to each one of my associates, I
owe much on the score of comity and personal amenity and forbearance;
and I have been made to feel, in the remotest solitudes, how easy it is
to execute a duty when all conspire to facilitate it.
The views herein expressed are generalized in two geological maps
(hereto prefixed), which, it is believed, will help to fix the facts in
the mind. They exhibit the facts noticed, in connection with the theory
established by them, and by all my observations, of the construction of
this part of the continent.
The mineralogy of the regions visited is condensed in the following
summary, drawn from my notes, which, it is believed, constitutes an
appropriate conclusion to this report.
With the exception of one species, namely, the ores of copper, the
region has not proved as attractive in this department as I found the
metalliferous surface of Missouri. There are but few traces of mining,
and those of an exceedingly ancient character, in the copper region of
Lake Superior. The excavations in search of lead ore on the Upper
Mississippi do not date back many years, but the indications are such as
to show that few countries, even Missouri, exceed them in promises of
mineral wealth.
I have employed the lapse of time between the termination of the
exploration and the present moment, to extend my mineralogical
observations to some parts of the Mississippi Valley which were not
included in the line of the expedition, but which were visited in the
following year, in the service of the Government, namely, the Miami of
the Lakes, and Wabash Valleys, the Cave in Rock Region in Lower
Illinois, and the Valley of the River Illinois. The whole is
concentrated in the following notices:--
_Tabular View of Minerals observed in the Northwest._
I. ORES.
_Genera._ _Species._ _Subspecies._ _Varieties._
{ Copper { Native copper. { Fibrous.
{ { Green carbonate of copper { Compact.
{ Lead Sulphuret of lead Common.
{ Zinc Sulphuret of zinc Blende.
{ { { Common.
{ { { Radiated.
METALLIC { { Sulphuret of iron { Spheroidal.
MINERALS { { { Cellular.
{ { { Hepatic.
{ Iron { Magnetic oxide of iron Iron sand.
{ { Specular oxide of iron. Micaceous.
{ { { Ochrey.
{ { Red oxide of iron { Scaly.
{ { { Compact.
{ { Brown oxide of iron Ochrey.
{ Silver.
II. EARTHS AND STONES.
_Genus._ _Species._ _Varieties._
{ { { Milky.
{ { { Radiated.
{ { { Tabular.
{ { Common { Greasy.
{ { quartz { Granular.
{ { { Arenaceous.
{ { { Pseudomorphous.
{ { { Amethystine.
{ { Amethyst
{ {
{ { Ferruginous {
{ { quartz { Yellow.
{ { { Red.
{ Quartz { Prase
{ { { Common.
{ { { Cacholong.
{ { Chalcedony { Carnelian.
{ { { Sardonyx.
{ { { Agate.
{ { Hornstone
{ { { Common.
{ { Jasper { Striped.
{ { { Red.
{ { Heliotrope
SILICIOUS { { OPAL COMMON.
MINERALS {
{ Silicious { Common.
{ slate { Basanite.
{
{ Petrosilex
{ { Common.
{ Mica { Gold yellow.
{
{ { Common.
{ Schorl { Indicolite.
{
{ Feldspar Common.
{ Prehnite Radiated.
{
{ Hornblende { Common.
{ { Actynolite.
{
{ Woodstone { Mineralized wood.
{ { Agatized wood.
{ { Calcareous {
{ { spar { Crystallized.
{ { { Lamellar.
{ { Granular
{ { limestone
{ {
{ { Compact { Common.
{ { limestone { Earthy.
{ {
{ { Agaric {
{ { mineral { Common.
{ Carbonate { { Fossil farina.
{ of lime {
{ { { Oolite.
{ { Concreted {
{ { carbonate { Calcareous { Stalactite.
{ { of lime { sinter { Stalagmite.
{ { {
{ { { Calcareous tufa.
CALCAREOUS { { Pseudomorphous carbonate
MINERALS { { of lime.
{ { Marl Ludus helmontii.
{ { Fibrous.
{ Sulphate { Granular.
{ of lime Gypsum { Granularly foliated.
{ { Earthy.
{ Fluate of
{ lime Fluorspar
_Genus._ _Varieties._
{ { Argillite.
{ Argillaceous slate { Bituminous shale.
{
{ Chlorite Chlorite slate.
{ Stautoride.
ALUMINOUS MINERALS { { Potters' clay.
{ { Pipe clay.
{ { Variegated clay.
{ Clay { Blue sulphated clay.
{ { Green sulphated clay.
{ Opwagunite.
{ Serpentine Common serpentine
MAGNESIAN MINERALS { Steatite Steatite.
{ Asbestus Com. asbestus.
BARYTIC MINERALS Sulphate of barytes Lamellar.
STRONTIAN Sulphate of strontian Foliated.
III. COMBUSTIBLES.
{ { Petroleum.
{ Bitumen { Maltha.
BITUMINOUS MINERALS { { Asphaltum.
{
{ Graphite Granular graphite.
{ Coal Slate coal.
IV. SALTS.
{ { Native salt.
Soda { Muriate of soda ..... { Salt springs.
{
{ Alkaline sulphate of Alum.
{ alumina
a. _Metallic Minerals._
1. COPPER.
This metal is frequently found, in detached masses, in the diluvial soil
along the southern shore of Lake Superior, and in the high and barren
tract included between Lakes Huron, Michigan, and Superior, and the
Mississippi River, as general boundaries. Thus, it has been found upon
the sources of the Menomonie, Wisconsin, Chippewa, St. Croix, and
Ontonagon Rivers, but most constantly, and in the greatest quantity,
upon the latter. There are many localities known only to the aborigines,
who appear to set some value upon it, and have been in the habit of
employing the most malleable pieces in several ways from the earliest
times. It occurs mostly in detached masses, resting upon, or imbedded
in, diluvial soil. These masses, which vary in size, are sometimes
connected with isolated fragments of rock. Such is the geognostic
position of the great mass of native copper upon the banks of the
Ontonagon, which has been variously estimated to weigh from two to five
tons. This extraordinary mass is situated at the base of a diluvial
precipice composed of reddish loam and mixed boulders and pebbles of
granite, greenstone, quartz, and sandstone and diallage rocks. The
nearest strata, in situ, are red sandstone, grauwacke, and greenstone
trap. A company of miners was formerly employed in searching for copper
mines upon the banks of this river. They dug down about forty feet into
the diluvial soil, at a spot where a green-colored water issued from the
hill. In sinking this pit, several masses of native copper were found,
and they discovered, as their report indicates, the same metal "imbedded
in stone." But the enterprise was abandoned, in consequence of the
falling in of the pit.
At Keweena Point, on Lake Superior, I found native copper along the
shore of the lake, constituting small masses in pebbles, and, in one
instance, in a mass of several pounds' weight, which was found in the
Ontonagon Valley. I also observed the green carbonate of copper, in
several places, in the detritus. The strata of this point appear to be
charged with this mineral, particularly in its native forms. Hardly a
mass of the loose rock is without some trace of the metal, or its oxides
or salts. It would be difficult, on any known principles, to resist the
testimony which is offered, by every observer, to favor the idea that
extensive and very valuable mines exist. The whole lake shore, from this
peninsula to the Montreal River, is replete with these evidences.
There are indications that this mineral pervades the rocks and soils, in
a radius of one hundred and fifty miles or more, south and west of this
central point. It has been discovered at the sources of the Menominee,
Chippewa, Montreal, and St. Croix, and even at more distant points.
At St. Peter's, in digging down for the purpose of quarrying the rock,
about eighteen inches depth of dark alluvium was passed; then a deposit
of diluvial soil, with large fragments of limestone, greenstone, quartz
rock, &c., about six feet; and, lastly, one foot of small pebbles, &c.,
constituting the copper diluvium. No large mass was found; nor any veins
in the rock.
2. LEAD.
The only ore of lead known to exist within the limits to which these
remarks are confined, is the sulphuret. In the year 1780, Peosta, a
woman of the Misquakee, or Fox tribe of Indians, discovered a lead mine
upon the west banks of the Mississippi, at the computed distance of
twenty-five leagues below Prairie du Chien, which the Indians, in 1788,
gave Julian Dubuque a right to work. This permission was partially
confirmed by the Baron de Carondelet, Governor of Louisiana, in 1796. No
patent was, however, issued; but Dubuque continued to prosecute the
mining business to the period of his death, which happened in 1810, when
the mines were again claimed by the original proprietors.
The ore is the common sulphuret of lead, or galena, which Dubuque stated
to have yielded him seventy-five per cent. in smelting in the large way.
He usually made from 20,000 to 40,000 pounds per annum.
I made a cursory visit to these mines, and found them worked by the Fox
Indians, but in a very imperfect manner. They cover a considerable area,
commencing at the mouth of the Makokketa River, sixty miles below
Prairie du Chien. Traces of the ore are found, also, on the east bank of
the Mississippi at several points. It occurs disseminated in a reddish
loam, resting upon limestone rock, and is sometimes seen in small veins
pervading the rock; but it has been chiefly explored in diluvial soil.
It generally occurs in beds having little width, and runs in a direct
course towards the cardinal points. They are sometimes traced into a
crevice of the rock. At this stage of the pursuit, most of the diggings
have been abandoned. Little spar or crystalline matrix is found in
connection with the ore. It is generally enveloped by a reddish, compact
earth, or marly clay. Occasionally, masses of calcareous spar occur;
less frequently, sulphate of barytes, green iron earth, and ochrey brown
oxide of iron. I did not observe any masses of radiated quartz, which
form so conspicuous a trait in the surface of the metalliferous diluvion
of the mining district of Missouri.
Sufficient attention does not appear to have been bestowed, by
mineralogists, upon the metalliferous soil of the Mississippi Valley. It
is certainly very remarkable that such vast deposits of lead ore,
accompanied by veins of sulphate of barytes, calc spar, and other
crystallized bodies, should be found in alluvial beds; and it would be
very interesting to ascertain whether any analogous formations exist in
Europe, or in any other part of the earth's surface. It is one of the
most striking features of this deposit, that the ore, spars, &c., do not
appear as the debris of older formations, and have no marks of having
been worn or abraded, like those extraneous masses of rock which are
very common in the alluvial soil of our continent. The lead ore and
accompanying minerals appear to have been crystallized in the situations
where they are now found. We should, perhaps, except from this remark
the species of lead called _gravel ore_ by the miners, which is in
rounded lumps, and is never accompanied by spars.
Sulphuret of lead is also found near the spot where the small River
Sissinaway enters the Mississippi, and two leagues south of it, upon the
banks of the River Aux Fevre, at both of which places considerable
quantities have been raised, and continue to be raised, for the purposes
of smelting, by the Fox and Sac tribes of Indians. At these places, it
is most frequently connected with a gangue of heavy spar and calcareous
spar, with pyrites of iron. I procured from a trader, at Dubuque,
several masses of galena crystallized in cubes and octahedrons.
In descending the Upper Mississippi, a specimen of galena was exhibited
to me, by a Sioux Indian, at the village of the Red Wing, six miles
above Lake Pepin, said to have been procured in that vicinity. Galena is
also reported to have been discovered in several places on the south
side of the Wisconsin River, and these localities may be entitled to
future notice, as furnishing important hints.
3. ZINC.
The sulphuret of zinc (black blende) is found disseminated in limestone
rock along the banks of Fox River, between the post of Green Bay and
Winnebago Lake. Although frequently seen in small masses, no body of it
is known to exist. I also found blende, in small, orbicular masses of
calcareous marl, along the east shore of Lake Michigan, between the
Rivers St. Joseph and Kikalemazo.
4. IRON.
This mineral is distributed, in several of its forms, throughout the
region visited, although but little attention has yet been directed to
its exploration. In the basin of Lake Superior it exists, in valuable
masses, in the form of a magnetic oxide, on the coasts of the lake
between Gitchi Sebing (Great River), called by the French Chocolate
River, and Granite Point. Specimens from Dead River (Riviere du Morts)
and Carp River, the Namabin of the Indians, in this district, denote the
latter to be the chief locality. It is the iron glance, and occurs in
mountain masses.
_Sulphuret of Iron._--This variety is found, in limited quantities, in a
state of crystallization, in clay beds, on the west shore of Lake
Michigan, between Milwaukie and Chicago. It is frequently in the form of
a cube or an octahedron. Some of the crystals are in lumps of several
pounds' weight, with a metallic lustre. Often the masses, on being
broken, are found radiated, sometimes cellular, and occasionally irised.
_Iron Sand._--The breaking-up and prostration of the sandstone and other
sedimentary formations, along the shores of lakes Michigan, Huron, and
Superior, liberates this ore in considerable quantities. It arranges
itself, on the principle of its specific gravities, in separate strata
along the sandy shores, where it invariably occupies the lowest position
at and below the water's edge. The shores of Fond du Lac, on Lake
Superior, may be particularly mentioned as an abundant locality.
_Micaceous Oxide of Iron._--In detached mass, among the debris of the
River St. Louis and of Fond du Lac. It exists in veins in the clay slate
which characterizes the banks of this river.
_Ochrey Red Oxide of Iron._ (Red ochre)--Is produced near a spot called
the Big Stone, on the head of the River St. Peter's. It is said to occur
in a loose form, in a stratum of several inches thick, lying below the
soil of a level dry prairie or plain. The Sioux Indians, who employ it
as a paint, make this statement. The color of a portion given to me by
them is of a bright red; and a considerable proportion of the mass is in
a state of minute division. Particles of quartz are occasionally mixed
with it. This ore of iron is also represented to be found in the
prairies north of Gros Point, along the west shore of Lake Michigan,
between Milwaukie and Chicago.
Ochrey red oxide of iron occurs on the shores of Big Stone Lake, at the
source of the St. Peter's River. A large spring rises from a level, dry
plain, a few feet beyond which the mineral occurs. The Indians, who
employ it as a pigment, take it up with their knives. The stratum is
about eight inches thick, but just below the surface it is mixed with
common earth. The spring of water is pure and unadulterated.
5. SILVER.
The belief in the existence of silver ore in the region of the lakes,
and particularly on Lake Superior, seems to have early prevailed. So
much confidence was placed in the reports of its existence, that Henry
tells when a company was formed in England for exploring the copper
mines of Lake Superior (A. D. 1771), they were impelled to the search
more from an expectation of the silver, which it was hoped would be
found in connection with it, than from the copper.[234]
[234] This metal has subsequently (namely, in 1844) been found to
constitute a percentage in the native copper of the Eagle River mines
of Lake Superior. Traces of it were found in a mass of native copper
found on the shores of Keweena Lake, by Mr. Moliday, in 1826. A mass
of pure silver was discovered in a boulder in the drift of Lake
Huron, west of White Rock, in 1824. These discoveries induce the
belief that this element will be found to be extensively present in
the eventual metallurgic operations of the Lake Superior basin.
b. _Silicious Minerals._
1. QUARTZ.
This interesting species being distributed in its numerous varieties
throughout the region visited, I shall confine my notices to a few
localities.
Subs. 1.--_Common Quartz._
Occurs in the form of large water-worn masses along the shores of Lakes
Huron, Michigan, and Superior. Also, in veins in the granite of Lake
Superior, and in the argillite of St. Louis River. These localities all
consist of the opaque varieties, with a slight degree of translucence
in some places. It exists in mass at Huron Bay, Lake Superior, and in
fragments of red jasper on Sugar Island, St. Mary's River.
1. _Radiated Quartz._--In detached masses on the Grange, and also at the
rapids of the River Desmoines, on the Upper Mississippi. At the Grange,
the crystals, which are usually minute, sometimes possess a cinnamon
color, or pass into a variety of crystallized ferruginous quartz.
2. _Tabular Quartz._--In small, flattened masses along the shores of
Lake Pepin. These masses are transparent, or only translucent. Their
color is generally white, but sometimes yellow. They appear to be
closely allied to chalcedony.
3. _Greasy Quartz._--In detached masses along the shores of Lake
Superior.
4. _Granular Quartz._--At the Falls of Puckaiguma, on the Upper
Mississippi, in large, compact beds rising through the soil. Also, in
some conditions of the cliffs commencing at the Falls of St. Anthony,
Carrer's Cave, &c.
5. _Arenaceous Quartz._--This is sometimes the condition of fine,
even-grained, translucent sand rock of the preceding localities.
Valuable as an ingredient of glass.
6. _Pseudomorphous Quartz._--On the shores of Lake Pepin, occasionally.
These masses appear to have taken their crystalline _impress_ from
rhomboidal crystals of carbonate of lime.
7. _Amethystine Quartz._--In the trap-rock of Lake Superior.
Subs. 2.--_Amethyst._
This mineral occurs most frequently in the condition of amethystine
quartz, in hexahedral prisms, lining the interior of geodes, in the bed
of the River Desmoines, and on the Rock Rapids, in the channel of the
Mississippi. The crystals which I have examined are generally limpid,
with a high lustre, and of a pale violet color. Sometimes the tinge of
color approaches to a full red, or is only apparent in the summit of the
crystal. These geodes are sometimes eight or ten inches in diameter,
with a rough and dark-colored exterior, often so nearly spherical as to
resemble cannon _balls_. Some of the finest specimens I have observed
from this locality are preserved in the museum of Gov. Clarke, at St.
Louis, Missouri.
Subs. 3.--_Ferruginous Quartz._
In amorphous masses, of a deep-red, brown, or yellowish-red color, along
the southern shore of Lake Superior. Likewise, crystallized, in very
minute hexagonal prisms, terminated by six-sided pyramids, of a reddish
color, on the summit and declivities of the Grange de Terre.
Subs. 4.--_Prase._
In the drift of Lake Superior. Its color is a light green and not fully
translucent. It possesses a hardness and a lustre intermediate between
waxy and resinous.
Subs. 5.--_Chalcedony._
1. _Common Chalcedony._--In globular or reniform masses imbedded in
trap-rock, on the Peninsula of Keweena, Lake Superior. It is found
sometimes in association with other quartz minerals. Its color is white
or gray, sometimes veined or spotted with red. Also, constituting the
interior lining of geodes at the rapids of Rock Island and the River
Desmoines. These geodes, on breaking, often present a mammillary
surface. In the form of translucent fragments, with a highly conchoidal
fracture, among the debris of the shores of Lake Pepin. These fragments
possess an extremely delicate texture, color, and lustre.
2. _Cacholong._--Some loose fragments of this mineral exist along the
west shore of Lake Michigan, between Green Bay and Chicago. These
fragments possess small cavities studded over with very minute and
perfect crystals of quartz.
3. _Carnelian._--This mineral occurs in fragments in the debris of Lake
Superior; also, in the amygdaloid; also, around the shores of the Upper
Mississippi. Its color is various shades of red, or yellowish red,
sometimes spotted or clouded, fully translucent, and occasionally
presenting a considerable richness and beauty. Most commonly, the
fragments are too small to be applied to the purposes of jewelry.
Sometimes it is seen in very regular spheroidal masses, which contain a
nucleus of radiated quartz. Some of the specimens would be considered as
sardonyx.
4. _Agate._--Is found with the preceding. It is more frequently found
in larger masses, in the rock, which are sometimes spheroidal, reniform,
or globular. These agates are chiefly arranged in concentric layers,
which are white, red, yellow, &c., according to the colors of the
different varieties of chalcedonies, carnelians, &c., of which they are
composed. A close inspection would also separate them into several
varieties--as onyx, agate, dotted agate, &c.
Subs. 6.--_Hornstone._
In nodular or angular masses, imbedded in the secondary limestone of the
west shores of Green Bay; and in the beds of argillaceous white clay
strata of Cape Girardeau, of Missouri. Also, on the hills of White
River, Arkansas.
Subs. 7.--_Jasper._
1. _Common Jasper._--In detached fragments, yellow, in the drift of Lake
Superior.
2. _Striped Jasper._--With the preceding. Most commonly, these specimens
consist of alternate bands of red and black, or brown.
3. _Red Jasper._--In quartz rock, Sugar Island, River St. Mary's,
Michigan. Masses of this mineral have been met in situ.
Subs. 8.--_Heliotrope._
A fine specimen of this mineral, now before me, was procured at the
mouth of the Columbia River, Oregon. It is in the form of an Indian
dart. Its color is a deep uniform green, variegated with small spots of
red; those parts which are green being fully translucent, the others
less so, or nearly opaque. This beautiful mineral is represented to have
been in common use by the Indian tribes of the Northwest Coast, for
pointing their arrows, previous to the introduction of iron among them.
It differs chiefly from the dotted jaspers of Lake Michigan, in its
translucence and green color.
Subs. 9.--_Opal._
Common opal occurs as a constituent of agate, along with chalcedony
rarely, in the drift on the south shore of Lake Superior.
2. SILICIOUS SLATE.
1. _Common._--In subordinate beds, in the argillite of the River St.
Louis, northwest of Lake Superior.
2. _Basanite_ (_Touchstone_).--In detached fragments in the drift on
Lake Superior, and along the banks of the Upper Mississippi generally.
3. PETROSILEX.
In large isolated masses in the bed of the Illinois River, on the
shallow rapids between the junction of the Fox and Vermilion Rivers. It
is mostly arranged in stripes or circles of white, gray, yellow, &c.,
resembling certain jaspers, or approaching sometimes to hornstone. The
bed of the Illinois River, at this place, is a species of gray
sandstone. Also, in detached fragments, on the south shore of Lake
Superior, intimately mixed with prehnite. In regard to the latter,
Professor Dewey, of Williamstown College, writes me: "I have received
from Dr. Torrey, a curious mixture of petrosilex and prehnite, in
imperfect radiating crystals, which was sent him by you and collected at
the West. He did not tell me the name, but examination showed what it
was. The association is singularly curious." The locality of this
mineral is Keweena Point, Lake Superior.
4. MICA.
Occurs rarely in the granite of Lake Superior. It is found in place on
the Huron Islands. Also, in minute folia, in the alluvial soil of the
Upper Mississippi. A beautiful aggregate, consisting of plates of
gold-yellow mica, connected with very black and shining crystals of
schorl, has been dug up from the alluvial soil of the Island of
Michilimackinac.
5. SCHORL.
1. _Common Schorl._--In crystals, in boulders of granite, at Green Bay.
2. _Tourmaline._--With the preceding.
6. FELDSPAR.
As an ingredient in the granite of Huron Islands, Lake Superior. Also,
in detached masses of granite along the west shores of Lake Michigan.
Also, in the form of prismatic crystals of a light-green color, in the
rolled masses of hornblende, porphyry, greenstone, and epidotic boulders
of Lakes Huron, Michigan, and Superior.
7. PREHNITE.
This mineral occurs at Keweena Point, on Lake Superior. It is found in
connection with isolated blocks of amygdaloid, of primitive greenstone,
and of petrosilex. Sometimes native copper, and carbonate of copper, are
also present in the same specimen. In some instances, a partial
decomposition has taken place, converting its green color into
greenish-white, or perfect white, and rendering it so soft as to be cut
with a knife. Sometimes the grains or masses of native copper are
interspersed among the prehnite, and slender threads of this metal
occasionally pass through the aggregated mass of greenstone, prehnite,
&c., so that, on breaking it, the fragments are still held together by
these metallic fibres.
8. HORNBLENDE.
1. _Common Hornblende._--Occurs as a constituent of the hornblende rocks
near Point Chegoimegon, Lake Superior. Also, at the Peace Rock, on the
Upper Mississippi, and in certain granite aggregates, and rolled masses
of porphyries, &c., around the shores of Lakes Huron, Michigan, and
Superior.
2. _Actynolite._--In slender, translucent, greenish crystals, pervading
rolled masses of serpentine, on the west shores of Lake Michigan.
9. WOODSTONE.
1. _Mineralized Wood._--In bed of the River Des Plaines, Illinois.
2. _Agatized Wood._--This variety of fossil wood is found along the
alluvial shores of the Mississippi and of the Missouri.
c. _Calcareous Minerals._
1. CARBONATE OF LIME.
Of a substance so universally distributed throughout the western
country, it will not be necessary to give many localities, and these
will be principally confined to its crystalline forms.
Subs. 1.--_Calcareous Spar._
_Crystallized Calcareous Spar._--This mineral occurs, in minute
rhomboidal crystals, in the calcareous rock of the Island of
Michilimackinac. Sometimes these crystals fill cavities or seams of the
rock, or are studded over the angular surfaces of masses of vesicular
limestone of that island. I also found this mineral at Dubuque's mines,
and in small crystals in the metalliferous limestone bordering the Fox
River, between the post of Green Bay and Winnebago Lake, where it is
associated with iron pyrites and blende.
Subs. 2.--_Compact Limestone._
In proceeding northwest of Detroit, this mineral is first observed, in
situ, on an island in Lake Huron. It is afterwards found to be the
prevailing rock along the south and southwest shores of Lake Huron. In
many places, it incloses fossil remains. Sometimes it is _earthy_, as at
Bay De Noquet, a part of Green Bay, on Lake Michigan, where it contains
very perfect remains of the terrebratula. (Parkinson.) In other places,
no remains whatever are visible, and the structure is firm and compact;
or even passes, by a further graduation, into transition-granular, of
which, it is believed, the west shores of Lake Michigan afford an
instance. It is most commonly based upon sandstone, which also contains,
in many places, the fossil organized remains of various species of
crustaceous animals, and of vegetables, sometimes, coal, &c.
Subs. 3.--_Agaric Mineral._
This mineral substance occurs in crevices and cavities in the calcareous
rock of the Island of Michilimackinac, Michigan.
Subs. 4.--_Concrete Carbonate of Lime._
1. _Calcareous Sinter._--In the form of _stalactites_ and _stalagmites_,
in a cave situated near Prairie du Chien, on the Upper Mississippi.
2. _Calcareous Tufa._--A remarkable formation of tufa is seen on the
east banks of the Wabash River, near Wynemac's Village, about ten miles
above the junction of the Tippecanoe. It extends for several miles, and
is deposited to the thickness of thirty or forty feet above the water,
forming cliffs which are covered with alluvial soil and sustain a growth
of forest trees. The precise points of its commencement and
disappearance were not observed. The structure is cellular or vesicular,
and resembles, in some places, a coarse dried mortar. It is very light,
and possesses a white color in inferior situations, but the surface is
somewhat colored by fallen leaves and other decaying vegetation. It
imbeds fluvatile shells and some vegetable remains, the species of which
have not been ascertained. The opposite, or west side of the river
consists of a kind of puddingstone, or caschalo, made up of pebbles of
quartz, &c., cemented by carbonate of lime, of a yellow color and
translucent. This beautiful aggregate is overlayed by a stratum, of
fifteen or twenty feet in thickness, of diluvial soil. These localities
fall within the limits of the State of Indiana; but on territories still
occupied, if not owned, by the aborigines.
3. _Pseudomorphous Carbonate of Lime._--This form of carbonate of lime
occurs in Pope County, Illinois, a district celebrated for its
fluorspar, lead, crystallized quartz, &c., and bearing the unequivocal
marks of a secondary formation. Scattered in large masses over the soil,
we observe compact limestone, with very perfect cubical, octahedral, or
other regular cavities, which have manifestly originated from crystals
of fluorspar. The most common _impress_ of this kind appears to have
resulted from two cubes variously joined--a form of appearance very
common to the Illinois fluates. Some of these cubical cavities exceed
three inches square; but in no case is any remaining portion of the spar
in these cavities, or anywise connected with the fragments of limestone
thus impressed, although, at the same time, the spar is very abundant in
the alluvial soil where these curious limestones are found.
2. SULPHATE OF LIME.
Subs. _Gypsum._
1. _Fibrous Gypsum._--In the alluvial soil of the St. Martin's Islands,
Lake Huron. The fibres are sometimes five or six inches in length, of a
white color and delicate crystalline lustre. Sometimes these fibrous
masses are partially colored yellow or brown, apparently from the clay,
or mixed alluvion, in which they are imbedded.
2. _Granular Gypsum._ }
3. _Granularly-Foliated Gypsum._ } With the preceding.
4. _Earthy Gypsum._ }
3. FLUATE OF LIME.
_Fluor-Spar._--On the United States Mineral Reserve, Pope County,
Illinois. This locality is abundant, and the mineral readily and
constantly to be obtained. I first obtained specimens in June, 1818, and
afterwards visited it in July, 1821. It is disseminated in loose masses
throughout the soil, and in veins in the calcareous rocks. The spot most
noted and resorted to, and where the original discovery was made, is
four miles west of Barker's Ferry, at Cave-in-Rock, on the banks of the
Ohio, and about twenty-six miles, by the course of the river, below
Shawneetown. It is situated in the midst of a hilly, broken region,
called _the Knobs_, a tract of highlands intervening between the banks
of the Ohio and the Saline. The distance of this range from north to
south, or parallel with the course of the Ohio, cannot be stated. It
probably extends from near the banks of the Wabash River to the Little
Chain of Rocks. Its breadth--from Barker's Ferry, west, to Ensminger's,
at the Saline, is about twenty miles. It thus separates, by a rocky
border, the prairies of the Illinois from the current of the Ohio River.
These knobs, wherever observed, bear the indubitable marks of secondary
formation, and may be stated to consist, essentially, of compact
limestone resting on sandstone. The sandstone is sometimes so much
colored by iron, and by globular or irregular masses of iron stone, as
to give that rock a very singular aspect. This may be particularly
instanced in the mural front of the Battery rocks on the banks of the
Ohio. Every part of this formation has more or less the appearance of a
mineral country; and it is already known as the locality of ores of
lead, iron, and zinc, of crystallized quartz, of opal, heavy spar,
crystallized pyrites, and of very perfect fossil madrepores. In one
place (near the head of Hurricane Island) this spar forms a very large
and compact vein, dipping under the bed of the Ohio. Where the rock has
been explored, it is found in connection with sulphuret of lead, but it
has been mostly procured, because most easy of access, in the alluvial
soil. I went out about half a mile west of the Ohio, where a new
locality has been opened, and, in removing about five or six solid feet
of earth, procured as many specimens as filled a box of fourteen inches
square. None of these were more than two feet below the surface. One of
these specimens is an irregular octahedral crystal, eight inches in
diameter. The color of these masses is various shades of blue, violet,
or red, sometimes perfectly white or yellow; and the form most commonly
assumed is a cube, sometimes truncated at two or more angles, or
variously clustered. The external lustre of the crystals, raised from
alluvial soil, is feeble, but quite brilliant when taken from veins and
cavities in the rock. These spars from the alluvion do not appear to
exist as rock debris, or fragments worn off from other formations, but
as original deposits. There are no marks of attrition. They appear as
much in place as the limestone rocks below. It should also be
recollected that this mineral tract is terminated by one of the greatest
and most valuable salt formations in the western country--that of the
Illinois Saline.
_Septaria: Ludus Helmontii._--This variety of calcareous marl is found,
in orbicular or flattened masses, along the eastern shores of Lake
Michigan, between the rivers St. Joseph's and Kalemazo. Its original
situation appears to be the beds of marly clay which form the banks of
Lake Michigan at these places, from which these masses have been
disengaged by the waves, and left promiscuously among the washed and
eroded debris of the shore. These masses are penetrated by numerous
seams and lines of calcareous spar, sometimes radiating star-like, or
intersecting each other irregularly. Occasionally, these seams are
filled with sulphuret of zinc, and in these cases the spar, if any be
present, is rose-colored.
d. _Aluminous Minerals._
1. ARGILLACEOUS SLATE.
1. _Argillite_, or _Common Argillaceous Slate_.--Along the banks of the
River St. Louis, at the Grand Portage, &c. It occurs in a vertical
position, embracing veins, or subordinate beds, of grauwakke, milky
quartz, chlorite slate, and silicious slate, &c. It is bounded on one
side by red sandstone, and on the other by an extensive tract of
diluvial soil.
2. _Bituminous Shale._--In detached masses, along the shores of Lake
Huron, between Fort Gratiot and Thunder Bay. It contains amorphous
masses of iron pyrites, of a yellow color and metallic brilliancy, which
soon tarnishes on exposure to the air.
2. CHLORITE.
_Chlorite Slate._--In subordinate strata in the argillite of the River
St. Louis.
3. STAUROTIDE.
In garnet-colored crystals, in detached blocks of mica-slate, in the
drift of Lake Huron. These crystals consist of two intersecting
six-sided prisms, truncated at both ends, forming the cross. They are
nearly opaque, or feebly translucent on the fractured edge.
4. CLAY.
1. _Plastic Clay._--Very extensive beds of this clay are seen along the
west shore of Lake Michigan, between Sturgeon Bay Portage and Chicago.
Its color is generally a light blue, verging sometimes into deep blue or
grayish-white. It is plastic in water, adheres strongly to the tongue,
takes a polish from the nail, and emits an argillaceous odor when
moistened or breathed upon. These beds of clay frequently contain iron
pyrites, both in the crystallized and amorphous state.
2. _Pipe Clay._--In the flats of the St. Clair and Lake George,
Michigan. A bed of clay, apparently answering to this description,
exists at White River, Lake Michigan. Its color is a grayish-white,
verging to blue. It is very unctuous and adhesive when first raised, but
acquires more or less of a meagre feel as it parts with its moisture,
drying in firm and compact masses.
3. _Variegated Clay._--On the banks of the River St. Peter's, Upper
Mississippi. Neither the quantity in which it exists, nor the precise
locality is known. Its color is white, variegated with stripes, spots,
or clouds of red or yellow.
4. _Azure Blue Clay of St. Peter's._--The locality of this substance, as
communicated by the Indians, is the declivity of a hill, in the rear of
the village of Sessitongs, one mile above the confluence of the Terre
Blue River with the St. Peter's. It is found near the foot of this hill,
between two layers of sandstone rock, in a vein about fifteen inches in
thickness. This vein is elevated about twenty feet above the waters of
the Terre Bleu, and does not extend far in the direction of the river.
Having been resorted to by the Sioux Indians a long time, a considerable
excavation has been made, but the supply is constant. The color of this
mineral substance (its distinguishing character) is an azure copper
blue of more or less intensity. It is ductile and moderately adhesive,
when first taken up, or when moistened with water, but acquires an
almost stony solidity on drying. It is considerably adulterated with
sand or particles of quartz. It parts with its moisture rapidly on
exposure to the atmosphere, and dries without much apparent diminution
of volume.
5. _Green Clay of St. Peter's._--This differs little from the preceding,
except in its color, which is a deep or verdigris green, admitting some
diversity of shades. Its composition appears to be, essentially,
alumina, silica, carbonate of copper, water, and iron.
6. _Opwagunite_; _Calamet Stone_; _Pipe Stone._--The last of these terms
is a translation of the first, which is Algonquin. Under these names, a
peculiar kind of stone, which is much employed by the Indians for pipes,
has been alluded to by travellers and geographers from the earliest
times. It appears to be a variety of argillaceous wacke. Its color is
most commonly a uniform dull red, resembling that of red chalk.
Sometimes it is spotted with brown or yellow, but these spots are very
minute, and the colors usually faint. It is perfectly opaque, very
compact in its structure, and possessing that degree of hardness which
admits its being cut or scraped with a knife, or sawed without injury to
a common hand-saw, when first raised from the quarry; but it acquires
hardness by exposure, and even takes a polish. But it is not capable of
receiving a polish by the usual process of rubbing with grit-stone and
pumice, these substances being too harsh for it. The Indian process is
to scrape or file it smooth, and give it a polish by rubbing with the
scouring rush. Its powder is a light red, and emits an argillaceous odor
when wetted. This substance is procured at the Coteau des Prairie,
intermediate between the sources of the St. Peter's and the Great Sioux
Rivers. Some other places have been mentioned as affording this mineral,
particularly a locality on the waters of Chippewa River; but the mineral
procured here is chocolate-colored.
e. _Magnesian Minerals._
1. SERPENTINE.
At Presque Isle Point, Lake Superior, common and precious, in isolated
masses; also, in connection with, and imbedding native copper, along
the southern shore of Lake Superior, at Ontonagon River, &c.
2. STEATITE.
At Presque Isle, near River au Mort, Lake Superior, in connection with
the serpentine formation. Also, at the Lake of the Woods, of a black or
very dark color, where it is employed by the Indians in carving pipes.
3. ASBESTOS.
_Common Asbestos._--In serpentine and steatite, at Presque Isle Point,
Lake Superior. Also, in minute veins, in detached masses of diallage and
serpentine rocks, on the west shore of Lake Michigan. These veins are no
more than a fourth of an inch in width; and the fibres of asbestos occur
transversely. They are very flexible, and easily reducible into a
flocculent mass.
f. _Barytic Minerals._
SULPHATE OF BARYTES.
_Lamellar Sulphate of Barytes._--In detached masses, imbedded in
diluvial soil, at the mines of Peosta, or Dubuque, on the Upper
Mississippi, where it is accompanied by sulphuret of lead, calcareous
spar, &c. Also, at the Mine au Fevre (now Galena), and at the mouth of
the Sissinaway River, on the east banks of the Mississippi, between
Prairie du Chien and Fort Armstrong. Its colors are white or yellow, and
it is frequently incrusted with a thin coat of yellow oxide of iron. It
is most commonly opaque. The only translucent specimen seen was procured
at Dubuque's mines.
g. _Strontian Minerals._
SULPHATE OF STRONTIAN.
_Foliated Sulphate of Strontian._--At Presque Isle (Wayne's Battle
Ground), on the Maumee River, Wood County, Ohio. It occurs in veins and
cavities, in compact limestone, most commonly in the form of flattened
prisms. Its color is blue, frequently a very light or sky-blue, and the
crystals are fully translucent, or even transparent. In some instances,
they appear to have suffered a partial decomposition, and fall into
fragments in the act of raising, or are covered with a white powdery
crust, frequently visible only on the summits or terminating points of
the prisms. The same limestone yields crystallized calcareous spar. Both
these substances are abundant in the rocky banks and in the bed of the
Maumee. Also, on Grosse Isle, Detroit River, Michigan.
h. _Bituminous Minerals._
1. BITUMEN.
_Petroleum._--Occurs in cavities, in loose fragments of limestone rock,
along the west shore of Lake Michigan, between Milwaukie and Chicago.
These masses of rock lie promiscuously among fragments of quartz,
granite, sandstone, fossil madrepores, &c., along the alluvial shore of
the lake, and appear to have been washed up from its bed. The petroleum
is in a free and liquid state; but, where it has suffered an exposure to
the atmosphere, it has acquired a stiff and tar-like consistence passing
into _maltha_. Not unfrequently, fragments of mineral coal are also
found scattered along these shores, and there is reason to conclude that
a bituminous formation exists in the contiguous inferior strata forming
the basin of the lake.
2. GRAPHITE.
_Granular Graphite._--In a small vein, in the clay-slate of the River
St. Louis, at the head of the nine-mile portage. It is coarse-grained
and _gritty_.
3. COAL.
_Slaty Coal._--The only spot where this mineral has been observed, in
situ, is at La Charbonniére, on the west banks of the Illinois River, at
the computed distance of one hundred and twenty miles south of the post
of Chicago. It is here seen in horizontal strata, not exceeding two or
three inches in thickness, interposed between layers of sandstone and
shale. Breaking out on the declivity of the bank of the river, where the
overlaying strata are constantly crumbling down, and thus obscuring the
seams, no very satisfactory examination could be made in a hasty visit;
but the nature and position of the rock strata and soils, and the
general aspect of the country, do not justify the conclusion that the
bed is of much thickness or extent. Valuable beds may be discovered,
however, by exploring this formation. This coal has a shining black
color, a slaty structure, inflames readily, burning with a bright flame.
It is very fragile where exposed to the weather, falling into fine
fragments. Hence, a very black color has been communicated to the
contiguous and overlaying soil, which is manifestly more or less the
result of disintegrated coal.
Detached fragments of coal, corresponding in mineral characters with the
above, are occasionally found around the southern shores of Lake
Michigan. The inference, as to the existence of coal around the shores
of this lake, is obvious. And we are led to inquire: Does the La
Charbonniére formation of coal exist in the sandstone and limestone
strata forming the table-land between the Illinois River and Lake
Michigan, and reappearing around the basin of the latter, but at such a
depression below its surface as to elude observation? And, if so, does
not this coal formation extend quite across the southern portion of the
peninsula of Michigan? The secondary character of the region alluded to,
so far as observed, the horizontal and relative position of the strata,
and the general uniformity which is generally observed in the species
and order of the coal measures, favor this suggestion.
i. _Soda._
1. MURIATE OF SODA.
No traces of salt are known to have been discovered in those parts of
the territory of the United States situated north of latitude 46° 31´
(which is that of the Sault Ste. Marie) and _east_ of the Mississippi
River. The great secondary formations which pervade the western country
cease south of this general limit, and with them terminate the salt
springs, the gypsum beds, the coal measures, and other connected
minerals which are generally found in association. It is one of the most
important facts which the science of geology has contributed to the
stock of useful information, that, in the natural order of the rocky and
earthy deposits, muriate of soda always occupies a position contiguous
to that of gypsum. This intimate connection between the sulphate of lime
and the muriate of soda, enables us, by the discovery of the one, to
predict, with considerable but not unerring certainty, the presence of
the other. It adds weight to an observation first made among the salt
formations of Europe, to find its general correctness corroborated by
the relative position of these substances in the United States. These
remarks will apply particularly to the salt formations of New York, and
to some portions of the muriatiferous region of Virginia and the
Arkansas.
There appears to be a salt formation extending from the northwest angle
of the Ohio through Michigan, for a distance of two hundred to three
hundred miles. It commences in the Seweekly country, passing around the
Sandusky River of Lake Erie, where an extensive bed of granular gypsum
has recently been discovered, and continues, probably, northwest, so as
to embrace the Saganaw basin, and reach quite to the end of the
peninsula, and embracing, perhaps, the Gypsum Islands of Lake Huron, ten
miles northeast of Michilimackinac. All the brine springs and gypsum
beds noticed in the region are situated in the line of this formation.
During the fall of 1821, a number of gentlemen at the Island of
Michilimackinac united in the expenses of a tour for exploring the
Skeboigon River, a stream which originates in the peninsula of Michigan,
and flows into Lake Huron opposite the Island of Bois Blanc. The
particular object of this party was to ascertain the precise locality of
certain salt springs reported to exist upon that stream. They proceeded
to the places indicated, and examined several springs more or less
impregnated with salt, but reported that, owing to the jealousy and
hostility of those bands of Indians who were found upon that stream,
they were not enabled fully to accomplish the object in view.
There are several salt springs reported to exist near the Indian village
of Wendagon, on the Sciawassa River, and others on the Titabawassa
River, the principal tributaries of the Sagana. Little is, however,
known respecting these springs, but the water is represented to be so
strongly impregnated, that the Indians manufacture from it all the salt
necessary for their villages.
Grand River Valley has also been mentioned among the localities of salt
water and gypsum rocks.
Hints may thus be derived of value to the future commerce of the
country. Scarcely any of the new states are without indications of the
existence of salt. Every day is adding to the number of localities.
In the region _west_ of the Mississippi, I was informed that salt
occurs, in the crystallized form, in the territories of the Yanktons,
who inhabit the flat country at the sources of the River St. Peter's. In
certain parts of these plains, the salt exists on the surface. It is
mixed with earth, in specimens brought to me, but crystallized in cubes,
very imperfect, of a gray or grayish-white color. The Indians scrape it
up from certain parts of the prairies or plains, where the salt water is
prevented from draining off.
2. ALKALINE SULPHATE OF ALUMINA.
This salt exists, in the form of efflorescences, in the cavities and
fissures of rocks along the southeast parts of the shores of Sagana Bay,
Lake Huron, and in the argillaceous formations at Erie, on Lake Erie,
Pennsylvania.
* * * * *
These positions embrace the principal localities of minerals noticed. In
travelling rapidly through a remote wilderness, there was but little
opportunity to explore off the track; and the whole observation was
confined to the mere surface of the country, which is much obscured by
diluvial and alluvial formations.
It will be seen that the region of Lake Superior has been a fruitful
field for mineralogical inquiry, and it is one which invites further
exploration. Its mineralogy affords a variety of interesting substances
which are objects of scientific research, and it may be anticipated to
be the future theatre of extensive mining operations. The country
northwest of Lake Superior, and the Upper Mississippi north of the Falls
of St. Anthony--consisting mostly of upheaved primitive rocks and the
pebble-drift, or diluvial, formations--has furnished but few subjects of
mineralogical remark.
The district of country between the Falls of St. Anthony and Prairie du
Chien, in common with the more southern portions of the Mississippi
Valley, partakes of all the interest which the mineral kingdom presents
in a calcareous and metalliferous country of secondary formation. It
has added considerably to my collection. It is probable the Rivers St.
Peter's, St. Croix, and Chippeway would well reward exploration; but the
mines of Dubuque particularly invite a mineralogical survey. Their
future importance cannot fail to be duly appreciated.
If the country has put on an aspect unfavorable to mineralogy, its
geological features have been observed to sustain its interest.
Much of the interest growing out of the examination, for the first time,
of the mineralogy and natural history of the country, is such as to
commend itself, in an especial manner, to the consideration of men of
science, and of associations devoted to scientific details, rather than
the department of a government. To these former, nature is a storehouse
of facts, and a perpetual anxiety is felt by this class of observers to
know the range, not only of our rock formations, but of our plants,
shells, fossils, and other classes of objects in our physical geography.
Such desires I have endeavored, as far as my means permitted, to
gratify. The fresh-water conchology of the lakes and rivers visited was
often attractive, when other objects excited little interest. The
species collected in this department have been referred to the New York
Lyceum of Natural History.
With these remarks, the result of an arduous and interesting journey
through a part of the continent hitherto unexplored, I have the honor to
conclude my report, and to terminate the trust confided to me.
I am, sir, with respect,
Your obedient servant,
HENRY R. SCHOOLCRAFT,
_Geologist, &c. of the Ex. Exp._
VIII.
(A.)
_A Report to the Senate of the United States, in Answer to a
Resolution passed by this Body, respecting the Value and Extent of
the Mineral Lands on Lake Superior._[235] By HENRY R. SCHOOLCRAFT.
[235] _To the Senate of the United States:_--
In compliance with a resolution of the Senate of the 8th May last,
requesting "information relative to the copper mines on the southern
shore of Lake Superior, their number, value, and position, the names
of the Indian tribes who claim them, the practicability of
extinguishing their titles, and the probable advantage which may
result to the Republic from the acquisition and working these mines,"
I herewith transmit a report from the Secretary of War, which
comprises the information desired in the resolution referred to.
JAMES MONROE.
WASHINGTON, 7th December, 1822.
DEPARTMENT OF WAR, 3d December, 1822.
The Secretary of War, to whom was referred the resolution of the
Senate of the 8th May last, requesting the President of the United
States "to communicate to the Senate, at the commencement of the next
session of Congress, any information which may be in the possession
of the Government, derived from special agents or otherwise, showing
the number, value, and position of the copper mines on the south
shore of Lake Superior, the names of the Indian tribes who claim
them, the practicability of extinguishing their title, and the
probable advantage which may result to the Republic from the
acquisition and working these mines," has the honor to transmit a
report of Henry R. Schoolcraft, Indian agent at the Sault of Ste.
Marie, on the copper mines in the region of Lake Superior, which
contains all the information in relation to the subject in this
department.
All which is respectfully submitted.
J. C. CALHOUN.
To the PRESIDENT OF THE UNITED STATES.
SAULT STE. MARIE, October 1, 1822.
SIR: In reply to the inquiries, contained in a resolution of the Senate
of the United States, respecting the existence of copper mines in the
region of Lake Superior, inclosed to me in a note from the War
Department, dated 8th May, 1822, I have the honor to submit to you the
following facts and remarks:--
1. In relation to "_the number, value, and position of the copper mines
on the south shore of Lake Superior_." The remote position of the
country alluded to, the infrequency of communication, and the little
reliance to be placed on information derived through the medium of the
aborigines or of traders, who are wholly engrossed with other objects,
presents an embarrassment at the threshold of this inquiry, which must
be felt by every person who turns his attention to the subject. The
information sought for demands a minute acquaintance with the natural
features and mineral structure of the country, which can only be
acquired by personal examination; and it is a species of research
requiring more leisure, better opportunities, and a freer participation
in personal fatigue, than usually falls to the share of tourists and
travellers. Not only are those difficulties to be encountered which are
inseparable from the collection of isolated facts in a new and unsettled
country, but those, also, which are peculiar to the subject, connected
as it is, at every stage of the inquiry, with the prejudices and
superstitions of the Indian tribes. [B.] It can, therefore, excite
little surprise that, after having been the theme of speculation for
more than a century, and obtained the notice of several works of merit
in Europe,[236] both the position and value of these mineral beds have
continued to the present times to be but partially known. To ascertain
more clearly their value and importance to the Republic were objects
more particularly confided to me as a member of the expedition sent by
the Indian Department, in the year 1820, to traverse and explore those
regions. My report of the 6th of November of that year--a copy of which,
marked A, is herewith transmitted--gives the result of that inquiry.
After a lapse of two years, little can be added. Reflection and
subsequent inquiry convince me that the facts advanced in that report
will be corroborated by future observation. No circumstance has
transpired which is calculated to prove that my suggestions with regard
to the fertility and future importance of those mines are fallacious; on
the contrary, all information tends to strengthen and confirm those
suggestions. Specimens of pure and malleable copper continue to be
brought in to me by the aborigines from that region, but it is not
deemed necessary to particularize in this place the additional
localities. It will be sufficient to observe, that the number of these
new discoveries justifies the expectations that have been created
respecting the metalliferous character of the region of the Ontonagon,
and the south shore of Lake Superior. [C.]
[236] _Vide_ Jameson's Mineralogy, Parkes's Chemical Catechism,
Phillips's Elementary Introduction to Mineralogy.
I shall here add the result of an accurate analysis made upon a specimen
of this copper at the mint of Utrecht, in the Netherlands, at the
request of Mr. Eustis, minister plenipotentiary from the United States,
who carried samples of the American copper to that country. The report
of the inspector of the mint, which communicates the result of this
analysis, has the following remarks upon the natural properties of this
species of copper, and the mode of its production: "From every
appearance, the piece of copper seems to have been taken from a mass
that has undergone fusion. The melting was, however, not an operation of
art, but a natural effect caused by a volcanic eruption. The stream of
lava probably carried along in its course the aforesaid body of copper,
that had formed into one collection, as fast as it was heated enough to
run, from all parts of the mine. The united mass was probably borne in
this manner to the place where it now rests in the soil. The
crystallized form, observable everywhere on the original surface of the
metal that has been left untouched or undisturbed, leads me to presume
that the fusion it has sustained was by a process of nature; since this
crystallized surface can only be supposed to have been produced by a
slow and gradual cooling, whereby the copper assumed regular figures as
its heat passed into other substances, and the metal itself lay exposed
to the air.
"As to the properties of the copper itself, it may be observed that its
color is a clear red; that it is peculiarly qualified for rolling and
forging; and that its excellence is indicated by its resemblance to the
copper usually employed by the English for plating. The dealers in
copper call this sort _Peruvian copper_ to distinguish it from that of
_Sweden_, which is much less malleable. The specimen under consideration
is incomparably better than Swedish copper, as well on account of its
brilliant color as for the fineness of its pores and its extreme
ductility. Notwithstanding, before it is used in manufactures, or for
the coining of money, it ought to be melted anew, for the purpose of
purifying it from such earthy particles as it may contain. The
examination of the North American copper, in the sample received from
his excellency the minister, by the operation of the cupel and test by
fire, has proved that it does not contain the smallest particle of
silver, gold, or any other metal." It is a coincidence worthy of remark,
that the suggestions offered by the assayer respecting the volcanic
origin of these masses of copper, are justified by the leading features
of the Porcupine Mountains, and by the melted granites found upon the
heights called Grande Sables and Ishpotonga.
2. The second and third inquiries of the resolution relate to "_the
names of the Indian tribes who claim the mines, and the practicability
of extinguishing their title_." By the treaty concluded at this post on
the 16th of June, 1820, the Ojibwai[237] Indians cede to the United
States four miles square of territory, bounded by the River St. Mary's,
and including the portage around the falls.[238] This is the most
northerly point to which the Indian title has been extinguished in the
United States. The different bands of Ojibwais possess all the country
northwest of this post, extending through Lake Superior to the sources
of the Mississippi, where they are bounded by the Assennaboins, the
Crees, and the Chippewyans of the Hudson Bay colony. Their lands extend
down the Mississippi to the Sioux boundary, an unsettled line between
the junction of the River De Corbeau and the Falls of St. Anthony. South
of Lake Superior, they claim to the possessions of the Winnebagoes, on
the Ouisconsin and Fox Rivers, and to those of the Pottawatamies and
Ottoways, on Lake Michigan. The Wild Rice, or Monomonee Indians, are an
integral part of the Ojibwai nation, deriving their name from the great
reliance they place on the zizania aquatica as an article of food. They
live in small, dispersed bands between the Ojibwais of the lake, and the
Winnebagoes of Fox River. Those residing among the Ojibwais speak the
same language, but with many peculiarities and corruptions on the waters
of Green Bay. They claim the respective tracts upon which they are
located. These are, principally, the valleys of the Fox and Monomonee
Rivers, and the rice lands contiguous to the Fol. Avoine, Clam Lake, and
Lac de Flambeau, which lie on the table-lands between Lake Superior and
the Mississippi.
[237] For the different names applied to this tribe of Indians, see
Appendix H.
[238] _Vide_ acts passed at the second session of the 16th Congress
of the United States, page 88.