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pectability as to the character and resources of the population engaged in the lead business of the Galena district, will in time lead to its development wherever it may be. When the present veins are exhausted, shafts will be sunk still deeper. There is, in fact, good reason to believe that the whole distance between the lead mines of Missouri and those of Dubuque's, is comprehended in the galeniferous formation. At Mineral point, a day's ride from Galena, there are also copper veins, indications of which I saw in coming down the Wiskonsan. The veins are nearly vertical, and the carbonate produces thirty-five per cent. of copper.

The Mississippi, from Fever river, continues about the usual breadth, but has comparatively few islands in it; the country is exceedingly beautiful, the banks abounding in gentle slopes, with scattering trees and occasional escarpments. In the vicinity of Rock river bituminous coal is found in many places, lying in the beds of the carboniferous limestone on both sides of the Mississippi, like those previously described in the State of Illinois. At the foot of the Des Moine rapids, near the place called Keokuk, the beds of carboniferous limestone are full of siliceous geodes, some of them a foot in diameter, and of great beauty and variety. In some instances I found the geodes containing accidental minerals; pearl spar covering the faces and terminations of the quartz crystals, and this again sprinkled over with a profusion of minute cubes of sulphuret of lead. Continuing down the Mississippi, along the bluff of the carboniferous limestone, and passing the mouth of the Missouri, I reached the city of St. Louis, in the State of Missouri.

From this place the geology of the country south to Red river, and southeast to the Atlantic, has been already sketched out in my report of 1835.

I have the honor to remain, &c.,

G. W. FEATHERSTONHAUGH,
U. S. Geologist.

Section-when the edges of a series of beds show them. selves on the banks of a river, or in any escarp ment, as if the formation had been cut through, this is a natural section. Rivers cut through their beds usually by retrocession.

Seam-a thin parting between thicker deposites.
Sedimentary rocks-deposited from water.
Septaria-calcareous concretions, divided by irregular

lines of carbonate of lime into septa or chambers. Siphuncle-a tube passing through the septa of concamerated shells, to enable the animals to rise and sink in the water.

Stratum-a bed or deposite distinct from another bed. Stratified-deposites formed by beds lying upon and usaally parallel to each other.

Strike-the direction of the edges of beds at right angles to their dip, as we say to strike off in any given direction.

Synclinal-where the beds converge towards each other in concave lines.

Talus-a slope at the foot of an escarpment, formed of the fallen materials.

Unconformable-beds whose planes do not conform in parallelism to each other.

Unstratified-amorphous masses, without any appearance of stratification.

Zoophytes-animals producing coral rocks.

[Appended to the above report are twenty illustrative diagrams; a map of a reconnoissance of the St. Peter's river to its sources; and a map of a portion of the Indian country lying east and west of the Missisippi river, to the 46th degree of north latitude, made in the autumn of 1835, from personal observation: which maps and diagrams, the publishers regret that it is not in their power to place with the report in the Register of Debates. As frequent reference is made in this report to an "Examination of the ele

port.

Conglomerate-rocks formed of fragments of older rocks, usually rounded into the pebble form by the action of water.

Cleavage-lines in slates and other rocks which resemble the lines of stratification, but which run in a different direction. The intervention of a siliceous seam, or sometimes the position of fossils, will determine doubtful cases.

Formation-a bed or group of beds, deposited at an epoch independent of that during which the beds it lies between were deposited.

Goniatites-a chambered shell, with a siphuncle, spirally striated, resembling the ammonite and nautilus. Ichthyodorulites-defensive fin bones of an extinct sharklike species of fish.

Ignigenous rocks having their origin from fire, in contradistinction to those having their origin from water. Lignites-carbonated fossil wood,

Mural escarpment-perpendicular cliffs, presenting a section of beds like a wall.

Nacre the brilliant iridiscent appearance on the surface of some shells.

Outlier-a mass of rock detached from the general formation of which it once formed a part. Radiaria-animals including echinites, encrinites, &c. Rock-all beds, whether hard or soft, are, in geology, included in this term.

in 1834 by the same gentleman, it is deemed proper, in order to give a full view of what the United States Government has done, by its authority, in aid of the geolgical reconnoissances of the country, to include that report also, in connexion with this.-EDITORS.]

Geological report of an examination made in 1834, of the elevated country between the Missouri and Red rivers. By G. W. Featherstonhaugh, U. S. geologist. Printed by order of the House of Representatives.

WAR DEPARTMENT, February 17, 1835. SIR: I have the honor to transmit, herewith, together with a report of the officer in charge of the Topographical Bureau, the report of Mr. Featherstonhaugh, called for by a resolution of the House of Representatives of the 14th instant.

Very respectfully, your most obedient servant,

surface they occupy, comparatively to the sea, as about one to three, is thought to be near two miles; whilst the sea is considered to have about an equivalent mean depth. If, therefore, at any period in the history of our planet, the mineral matter constituting the dry land has been distributed beneath the waters of the sea, an arrangement, as we perceive, very possible, and apparently probable, the planet would then have been entirely covered by water. In such a state of things, we have no cause to which to refer the origin of our continents and islands, save the expansive subterranean force before alluded to, which could raise them from the bottom of the ocean, and above its level. It is most satisfactory to reflect, that, without any reference to this theory, the progress of geological investigation has led the leading geologists in Europe to the conclusion that not only continents have been in this manner raised, but that all the important chains of mountains have in like manner been protruded from below; and, in many instances, the proofs are obvious, of the dislocation of the stratifications through which they have burst, to rear themselves to the lofty heights they have attained. It will be apparent to every one that successive upliftings of mineral matter would displace an equivalent cubic quantity of water, and that in proportion to the amount of mineral matter protruded, would be not only a corresponding agitation of the adjacent ocean and formations of currents, but an abrasion and partial destruction of pre-existing lands, the ruins of which, often extremely broken down and comminuted, would be deposited at the bottom of the ocean, to be again, at some future period, like sedimentary beds derived from whatever sources, elevated above its level.

In these direct and indirect operations of the expansive power beneath the crust of the globe, have been perceived the happy means of compromising the conflicting views entertained respecting many important geological phenomena; since both the results of igneous action and aqueous deposition can be referred to the same cause, as well as the paradoxical appearance of rocks of the same class, of undisputed igneous origin, which have been observed at the lowest depths of the crust of the globe, and at its most elevated summits; these latter being evidently thrust up from below.

The application of these views of subterranean action, which are not sketched here from a theoretical predilection, will be found highly important in relation to the structure and continuity of metallic veins. The mineral resources of the United States appear to be commensurate with the grandeur of its other physical features, whilst there is still much hesitation about the introduction of systematic mining. It was a prevailing opinion, whilst the Wernerian theory obtained, that metallic veins were filled in by deposites from above; and it has been extensively believed in this country that the galena, or sulphuret of lead, found in the State of Missouri, was a mere superficial deposite. Opinions of this kind operate powerfully to restrain capitalists from giving their confidence to mining undertakings in an efficient manner; they are afraid to invest their means beyond an amount necessary to conduct partial diggings and excavations near the surface; whereas, if they were satisfied of the reasonableness of the opinion that metallic veins have their origin from below; that the veins, which have repaid them "moderately near the surface, are generally considered to improve at a depth of five hundred feet; that they have been successfully followed up and cut out at three times that depth, and that we have no practical evidence of their want of continuity to infinitely greater depths, they would not hesitate to sink their shafts and establish their works upon a scale of magnitude corresponding with their confidence, and producing results favorable to national industry and to their own just expectations.

But laying aside this branch of the subject at present, and reverting to the supposed igneous central action of this

planet, it would seem to invite an important consideration, whether, if this action be general, the results produced by it may not, with some modifications, be expected to present a close affinity in their general character throughout the globe.

The European geologists have examined the structure of a great portion of their eastern continent with unrivalled perseverance and energy, having brought to the considera. tion of its phenomena all the acumen of which mineralogi. cal and chemical learning is almost susceptible; and now their most eminent men call for geological investigations of this western continent as most important desiderata in physical science. It has been deemed by them necessary, for the further advancement of the science, to have a com parison instituted between the geological formations of this western world and their own portion of the globe, in order to determine how far the phenomena common to both belong to causes which have been cotemporaneous, or of the same class; whether the principles which have determined the structure of the one, have been the governing cause in the other, and to what causes any discrepancy may be assigned.

This inquiry is of deep interest to this country, not simply as one which leads us into a field of philosophical research, highly favorable to enlargement of the intellectual powers, but as pregnant with utility in relation to the business pursuits of life, enabling us to apply the fruits of their long and rich experience to the immediate development of the mineral resources of this country, and returning to them some measure, at least, of information for those inestimable labors which have preceded our own investigations. Strongly impressed with these views, I have constantly endeavored to make them auxiliary to my late examinations. In concisely submitting the arrangement of rocks, as it is declared to exist, and as I have observed it in Europe, with a comparative view of the principal formations in those parts of the United States I have lately visited, I shall not advert to the numerous divisions into which the whole known series of rocks has at various times been thrown. The voluminous literature belonging to modern geology has produced numerous classifications from the geologists of France and Great Britain, all of which, however useful in the study of the science, appear destined to fluctuation and change in its progress, like the graceful and waving lines formed by the rippling on the sea beach, which are modified or obliterated by every new breeze impressing the coming tide. From circumstances no longer subject to control, the science and letters of Great Britain will forever become an inherent part of the intellectual power of this country. The old and simple divisions of primitive, transition, secondary, and tertiary, to which the English geologists so long adhered, and which have been adopted in this country from their elementary works, are, it is true, not free from objections, but they are convenient and familiar here; and since all classifications are imperfect, and subject to change, I have thought it best, where classification must be resorted to for purposes of illustration, to use that which is best known, with no disposition, however, to assign any value to it beyond the facility it gives me of making myself understood.

Geological observations, made in numerous parts of the world, have shown that the inferior part of the whole series of rocks is distinguished by characters which do not belong to the superior portion.

It is to a great degree unstratified; the lowest, amorphous masses, having a confused, irregular, crystalline, gran ular structure, composed usually of quartz, felspar, and mica, whence they have received the designation of granitc.

*Al. Brogniart, a rare example of learning and genius in France; Coneybeare and De la Beche, two of the most eminent geologists in Great Britain,

This rock, in some instances, is beautifully studded with crystals of felspar, and is then called porphyritic granite.

It contains metalliferous veins, bearing tin, copper, iron, gold, silver, and other metals.

From a careful study of all the circumstances attending them, it is now the general opinion that rocks of this class are the result of igneous fusion, and to which the term ignigenous is suited.

Other members of this inferior portion of the geological series, though partaking largely of the preceding characters of the granitic rocks, are very different in their external appearance. The rocks called gneiss, which are often found superincumbent on the granite, have a more regular arrangement of the planes of the mica contained in them, which give then frequently an appearance of stratification resembling that produced by deposition from water; how far this may be owing to a distribution of the plates of its mica parallel to its strata, and which appears to be the immediate cause of its fissility, cannot now be asserted: this, however, is true, that the granitic rocks and the gneiss pass sometimes into each other so completely, and the former are often so enclosed in the latter, that I have frequently on this continent taken specimens of the gneiss, especially from near Richmond, in Virginia, which, if placed in a cabinet, any mineralogist would pronounce a true granite; and certainly nothing is more common here than to observe broad veins of true granite passing into the beds of gneiss, and, indeed, the granite alternating with the gneiss.

There is another important rock, known under the name of mica slate, which is usually destitute of both felspar and hornblende. The gneiss, which contains more mica than hornblende, appears to pass into this, and the difference between them to be owing to the absence of

some of its constituents.

The other most important members of this inferior portion of the geological series, commonly called primitive rocks, are statuary limestone or white marble, serpentine, greenstone, quartz rock, the varieties of hornblende rocks and slates, and clay slate, the regularity in superposition of which to each other has not been satisfactorily established.

The rocks hitherto enumerated have one common character; they contain no organic remains, and may, therefore, properly be called inorganic, in relation to animal and vegetable bodies.

All these rocks, so different from each other in their external appearance, have, with the exception of the statuary limestone, no greater difference than is constituted by the presence or absence of some mineral constituent, or the difference of proportions. Some of the most important members, such as granite and gneiss, contain silex as a constant constituent, others contain magnesia, and some hornblende; but a serious study of the whole, and of the relation in which they stand to all other rocks, impresses a strong opinion that they owe their origin to the same cause, and that they have all, at some period, been either ejected from central depths by the expansive power generated there, or that they have been great intumescing masses, which, on cooling, have resolved themselves into various stages of crystallization, and that their varying products have been brought into fusion or solution from distinct central localities, some of the differences between

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them having been occasioned by a chemical action, more easily imagined by us than described.*

But these masses, both amorphous and stratified, contain granite and other veins, which have obviously passed through them subsequent to their original formation, since we see that, at their passage, the intruded rock has been dislocated from its continuity, and that a violence of subterranean origin attended it.

Nor has the laboratory of nature yet ceased its action; the granitic rocks, such as we find injected into their cognate masses, do not, it is true, flow from recent volcanoes; but the trap rocks, which are but modifications of primitive mineral masses, have been found injected into them in both hemispheres, and are still poured out of modern volcanoes in the form of lava. These intrusions of granitic and trappean matter, including the greenstones, are common to all the geological periods. In the Alps, modifications of the granitic rocks are found overlying fossiliferous strata, with small metalliferous veins in both formations, near the point of contact. All these intrusive bodies, from the most ancient granites to the modern lavas, appear to be modifications of each other, originating in the same cause, produced by the same means, but varying in their constituents, and the manner of their consolidation. Mr. Lyell states "that the lava in the crater of Stromboli, one of the Lipari islands, has been in a constant state of ebullition for the last two thousand years;" and as this must communicate with deeper foci, a central igneo-expansive power, in unceasing action, seems to form a great constitutional principle of the planet ; indeed, some inhabited parts of the globe are supposed to be in an actual state of gradual elevation. Yet these apparently fearful dynamics are but means in the hand of Providence to establish the most grand and beautiarrangements -mountains and continents raised from the deep to heights which afford salubrity and security, and where nature can offer the most varied and attractive residence to man and the animals; and the crust of the earth, prolific in minerals, with all useful and precious metals, in the proper proportions for our immediate wants.

Primitive rocks are found in all those parts of the earth which have been examined, and there is every reason to believe that they form the solid basis of the crust of the globe. A portion of this basis is now covered to great depths by the sedimentary rocks which have been subsequently deposited by water, but the surfaces of vast tracts of inhabited country are constituted by these primitive rocks. In the United States, they occupy the surface from

juxtaposition of amorphous and stratified masses, of ignigenous origin, *The alternation of the primitive rocks above alluded to, and the is susceptible of explanation, if fairly and patiently considered. Due weight, however, must be given to the circumstances under which the greatest number of cases present themselves. The stratified appear. ance of gneiss is unequivocal, and must be conceded. Before the rocks were forined which have an aqueous origin, the planet may have been in a quasi-incandescent state, as we now conceive of many astronomical bodies; nor can we conjecture to what period that state of incandescence extended. The presence of fossil plants of tropical constitutions in high northern latitudes shows a temperature for the globe unknown to the present order of things. In whatever manner the beds of gneiss were brought into contact with the ignigenous amorphous masses, whether by aqueous deposition, or by pourings out from below, in thick pasty solutions, we are certain they must have undergone a crystalline change on coming into contact with masses intensely heated. Wherever intrusive rocks, such as trap, which, like lava, was once mineral matter in a state of fusion, come into contact with formations that preceded them, a very great alteration in the texture of the intruded mineral is generally produced, as we know from numerous examples, both in this country and Europe, and which correspond to experiments made in the laboratory, from states of entire fusion to slight changes. It is thus that basaltic dikes have changed chalk into marble, sandstone into hornstone and quartz, and shale into jasper, as may be seen in the bank of the Hudson opposite the city of New York. Greenstone dikes have reduced coal into cinders, and sandstone into jasper, as at Magnet Cove, Arkansas. Mr. Lyell, in his celebrated work, vol. 3, p. 368, mentions a basaltic dike, which has produced crystals of analcime and garnet in a fossiliferous shale, and refers to the garnets often found in mica slate, as probably owing their origin to its being affected by caloric. In the neighborhood of Monrovia, on the Baltimore and Frederick railroad, very fine precious garnets are found in the gneiss. +Lyell's Principles of Geology, vol. 3, p. 371.