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But these beds not only contain proportional mixtures of living and extinct shells; species are found in them which are found in beds of the same age in Europe, of which, I have no doubt, the labors of Mr. Conrad, and other geologists engaged with the subject, will soon produce important lists. This might be expected from the close generic affinities of the fossils of both hemispheres.*

Having had personal opportunities of examining the beds of which I have been speaking, in the States of New Jersey, Maryland, Virginia, South Carolina, Alabama, and Arkansas, besides having seen the characteristic fossils of the subcretaceous beds from Tennessee, and from localities several hundred miles up Red river, beyond the limits of my late tour, I cannot but consider them, together with their fossil contents, as establishing a most satisfactory agreement between these portions of the geological series in Europe and America; and when we add to the list the lignites, and the equivalent quadrupedal and Saurian remains found in both countries, it may be asserted that there is no important discordance between the marine and fossil remains of their contemporaneous periods; for time will probably diminish the list of non equivalents on both sides. Within a very short period, the eurypterus, a remarkable fossil crustaceous animal, discovered some years ago in the United States, and then entirely unknown in Europe, has been discovered there.

It would be inconsistent upon this occasion to enter upon all those details requisite to bear me out completely in what I have advanced of the agreement of the European and American rocks, and which I must defer to more appropriate occasions. That opinion was communicated by me, as far back as the year 1828, to the Geological Society of Londoh. To those who are interested in geological results, without having studied the science, it will be still more satisfactory to know that this constant succession in the order of rocks, in respect of their superposition to cach other, is invariable, as much so as that of the order in which the letters of the alphabet stand to each other; so that this result, which it was my intention to show in entering upon this sketch of the principles of geology, will be apparent to them; that the study of the structure of this globe is not that of an inchoate mass, the parts of which were thrown together at random, but that all the parts of the globe which have been geologically examined, have contributed in turns to establish the now generally-received truth, that the crust of the earth contains a series of rocks that have come into existence in regular succession to each other after a particular and apparent design, and that all the principles of the science, as they are established in one country, can be successfully applied in every other country, for the promotion of human industry and prosperity. I now proceed to the results of my late tour.

I was well acquainted, by reputation, with the lead deposites in the State of Missouri, though I had not, as it turned out, any accurate idea of the geological structure of the country.

It was important for me to examine them, as they were situated amidst the public lands; and the southern part of the State of Missouri being conterminous with the Territory of Arkansas, where my instructions led me, I directed my course to the northern foot of the highlands which extend to the Missouri river, and which lie between it and Red river, with the intention of passing down them from 38° 30' north latitude, to their southern slope at 34° north latitude. In passing through the States of Tennessee, Kentucky, and Indiana, I had observed an unusual disposition in numerous beds of carboniferous limestone (some of which, in the two first States, contain sulphuret of lead, encased in compact sulphate of barytes) to pass into siliceous matter not only were the fossils, with

* Dr. Morton, in his Synopsis, has published a list, compiled by Mr. Conrad himself, of living shells "common to the European and American coasts of the Atlantic," consisting of twenty-four species."

few exceptions, all converted into flint or chert, but, in some instances, the beds were principally made up of continuous plates of siliceous matter, after the manner of the chalk flint in Europe. I subsequently found this to be very much the case in the State of Missouri, and in the vicinity of Herculaneum some of the calcareous beds consisted of about two-thirds of their bulk of silex.

This siliceous character in the rocks disappears to the north, and is not seen on the Missouri river. The limestone beds which I examined on the banks of this last river, and in adjacent situations, were either compact or argillaceous. Being desirous of re-examining the beds which the Mississippi has cut through east of the mining district in the State of Missouri, I recrossed the country to the Mississippi, and in the vicinity of Herculaneum found a great part of the calcareous beds contained about two-thirds of their bulk of silex. A little south of this last place, and about one mile north of the Plattin creek, the Mississippi being very low, I observed a change in the rocks. A bed of quartzose sandstone, which can only be observed at that stage of the water, and which is covered by a slight rise of the river, jutted out into the Mississippi. For some distance it had a loose granular texture, consisting of quartzose grains held together without cement. In some situations it crumbled between the fingers into sand, but in others it was sufficiently indurated to make a strong rock. The beds run into the bluff above it, which is a fetid limestone, of a sandy character, and contains sulphate of barytes. This was the first indication I found of an approach to the lead districts. The character of the limestone beds, as they are seen nearer to Herculaneum, is altogether changed here. Instead of compact limestone, with regular seams and blotches of cherty matter, I had suddenly come upon an extensive deposite of siliceous matter, without any lime, and which covered the lower limestone beds, and with calcareous beds superimposed on it, extremely siliceous. In neither of these deposites did I ever find any organic remains. South of these beds the banks of the Mississippi are low, and a valley intervenes, the disappearance of the solid contents of which is rendered less difficult to account for, by the want of tenacity in the rocks. From this point I again ascended the country in a direct west course, and soon got upon the extensive open barrens, with their straggling trees, which form the table land of that country, and which are constituted by the calcareo-siliceous fetid beds I had examined on the banks of the Mississippi, and which repose there also on the granular sandstone, as I had frequent occasions of discovering in the ravines and denuded depressions of the country. In one of these slopes, which was well uncovered by a perennial spring of some power, I saw lithographic stone, of a very good quality, lying amongst some thin beds of limestone. Pursuing a southwest course, I found the country broken and rolling, the heights principally constituted of sandstone, with limestone uniformly underlying it in the ravines. As I advanced, I found the mineral character of the country less simple, the rocks very much diversified with accidental minerals, and every thing announcing a metalliferous district. I became now desirous of finding some natural sections that would assist in explaining the phenomena around me, but I could find none, and could hear of none, so that it became necessary for me to examine the localities where mining operations were conducted, in order, by an examination of the subterranean arrangement of the metallic beds, to form some estimate of their direction and extension towards those parts of the country where the public lands lay. I accordingly visited the most ancient "diggings" which had been partially carried on ever since the French had had possession of the country, but I found that the irregular manner in which those diggings had been conducted almost baffled every attempt at systematic investigation. The sulphuret of lead, or "mineral," as it is

Geological Reconnoissance.

called in the lead country, has been, in certain localities, at all times found in fragments near the surface of the ground, from the size of a pin's head, in which it can be picked up in great quantities where the rain has washed the soil, to masses weighing several hundred pounds. Sometimes pieces of an intervening size are found, which have been affected by attrition; but, more frequently, the "mineral" preserves its angles very fresh, as it might be expected to do from its brittle cubic structure. Various opinions have been entertained of the cause of so singular a distribution of this mineral substance in loose pieces, and occasionally in such great quantities, near the surface of the earth--a circumstance which has occasioned the whole adjacent country where the mineral has been found, to be excavated into pits from six to twenty feet deep, so that in the localities of such districts it would be impossible to drive any carriage by daylight, and impracticable to ride securely on horseback by night. The disorder in which the country has been thus thrown, is entirely owing to ignorance of the geological structure of the country, and the commonest principles of mining, and is much to be regretted, as it will greatly embarrass future efforts, in those localities, at systematic mining. It would be superfluous to enter into any mineralogical detail of those diggings, or to render a very particular account of any of them, since nothing can be more rude than the attempts at collecting ore which they exhibit. In particular localities immense quantities of sulphate of barytes, or "tiff," as it is named, masses of quartz rock, cellular, and occasionally coated with mammillary crystals of great brilliancy, and, in other instances, a profusion of dark red clay, are thrown out of the diggings, together with the mineral.

It was at Mine la Motte I first received satisfactory evidence that the broken up mineral I had seen in the diggings had been occasioned by an accidental derangement of the regular structure of metallic veins, and to which I had always attributed these appearances.

The country around presents an extensive table land, almost denuded of timber, through which a few slight streams run, which are used to wash the soil taken out of the shallow diggings. The whole surface is cut out into pits of various sizes, from four feet diameter to some exceeding twenty feet square, with an equivalent depth. These larger areas have been the result of a discovery gradually made, that the loose fragments near the surface, which were formerly the sole object of the diggings, were I connected with mineral imbedded in the solid rock. Hence, large areas have been opened, without much relation to method, sometimes to the extent of half an acre, and gunpowder is employed to blast the metalliferous rock; so that mining in this particular district is become precisely what quarrying is every where else. The history of these diggings, and the manner in which the sulphuret of lead is often found, is as follows: The streams washing through the superficial gravels sometime disclose valuable deposites of the ore. Adventurers follow up these indications wherever found, and commence their diggings; when they reach a depth of twelve or fifteen feet, or as soon as it becomes inconvenient to throw out the earth, or hoist out the mineral, a new digging is commenced, and again abandoned for a new excavation. Frequently the superficial soil for about a foot will be red earth, mixed with mammillary quartz, called here "mineral blossom," and petro-siliceous stones; a deposite of red clay of a few feet is then generally found, resting upon a bed of gravel and flinty pebbles, in which the lumps and fragments, including extremely small pieces of ore, are found. Deposites of this kind do not differ, in any particular of mechanical arrangement, from any gravel deposites I have seen, especially the gravel deposites of gold in the Southern States, and which are, without exception, the detritus of rocks brought into these superficial beds by aqueous

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transportation. Beneath these free deposites lies the real metallic formation of the country, consisting of the fetid calcareo-siliceous rock before deseribed, frequently so much decomposed as to admit of being shovelled out, and traversed by horizontal brands of bright galena, or sulphuret of lead, sometimes one inch thick, and frequently a foot thick. In other situations, the ore is very much disseminated in the rock, although always confined in a vein or bandlike breadth, of different dimensions. Where the ore is much disseminated, and the rock is speckled with metallic particles for a great breadth, the ore is usually less productive, yielding about forty or fifty per cent. of lead, when the compact mineral in other situations yields sixtyfive per cent. Upon such occasions it appears to contain excess of sulphur. In some instances, I observed broad veins with a considerable dip, but generally the bands of ore were nearly horizontal. This locality appears to furnish a full explanation of the singular manner in which the ore and the sulphate of barytes, in which it is often sheathed, have come into that free and broken situation in which they are found in the superficial deposites. I observed veins at the top of the metalliferous formation, and beneath the superficial deposites, in quaries fifty feet across, and twenty feet deep, containing fragments of ore of various sizes, bright and sharp, with the vein, as well as that part of the rock through which it passed, much shattered and dislocated, the back of the vein being broken in numerous places, and the contents exhibiting strong marks of sudden violence. Sometimes the galena was rent into shivers, sometimes its horizontal sheet was broken up, and parts of the bright ore, ten inches wide, left standing on their edges, some in one direction, some in another, and the remainder left flat in its old place. In some places the phenomena resemble those presented in the chalk cliffs near the Isle of Wight, in England, where the beds are upset, and the seams and nodules of flint shivered. This is not the case, however, with all the veins. In various quarries at Mine la Motte, especially those which go by the name of Mine la Prairie, where more than half an acre of ground has been uncovered to a depth of twenty feet, the sulphuret of lead is not only seen running horizontally in hard compact veins in the calcareosiliceous rock, but is sometimes disseminated for a great extent, in specks through the rock, affording to the eye sufficient proof that the stony and metallic matter was deposited at the same time; for if either of them were abstracted, no principle of adhesion would be left for the remaining mineral: occasionally the rock changes its character, becoming either calcareous or siliceous altogether, and, indeed, the structure differs so much as to be sometimes hard, sometimes soft, sometimes granular, sometimes compact. Sometimes a bed of sandstone, three feet thick, will lie upon a seam of bright mineral six inches or a foot thick, though more generally it is much thinner, and lies in a flat plate. I have, however, seen it in veins of two feet thick. The deepest digging or quarrying I observed at this place did not exceed twenty-five fect; they had not yet begun a regular system of sinking shafts and cutting out drifts, but no doubt this will soon be done, as both the public and private lands around the whole region of Mine la Motte are, in my estimation, underlaid by rich veins of galena, that descend very deep towards the central parts of the earth. The superficial indications of this mineral are unerring.

On the approach to a mineral district, numerous localities present a confused, but distinct and rather unvarying character of crystallization. Imperfect nodules of siliceous matter, masses of mammillary quartz, the crystals of which are often superinduced upon chalcedonized concentric layers with an agate structure, indications of sulphate of barytes, with small fragments of sulphuret of lead in the rain furrows, betray the metalliferous rocks: these are the

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situations which are chosen to commence new diggings in, and with invariable success as far as respects the finding ore. But from some works which have been recently constructed, and which I had an excellent opportunity of examining, I am confident a thorough reform in the whole system of mining in that interesting country is about to take place, and that it will henceforward be conducted upon acknowledged principles, consistent with the true nature of metalliferous veins, and that economical administration of the mines which will enable them to contribute powerfully to the n tional resources.

These works, which, when I visited them, belonged to Messrs. Taplit & Perry, are distant four or five miles from Va'lee's mines, and about twenty-five miles from the point where I observed the quartzose sandstone jut out into the Mississippi. They are situated in a small valley at the foot of a ridge of calcareo-siliceous hills, and abound in the external indications I have before described. The proprietors, disregarding the superficial ores, and confiding in the metalliferous nature of the rock formation, had boldly sunk a shaft in imitation of some practical miners from England, on the other side of the hill, and had been rewarded with the most perfect success. In sinking this shaft, they had come, at random, at a depth of about sixty feet deep through decomposing calcareo-siliceous rock upon a vein of sulphuret of lead, and, going down, had reached another horizontal vein upwards of one foot thick, and throwing out from it numerous subordinate veins and threads, into all of which they had cut drifts, wherever the mineral was sufficiently abundant. They had sunk this shaft to a depth of about one hundred and ten feet, when I was there, and very obligingly let me down into it, and gave me every aid and facility in examining their works, which enabled me to observe the very curious structure of these metalliferous rocks, and to form a satisfactory opinion of the geological structure of all this remarkable country.

the large one I mentioned; but at the bottom of each of them was a thick bright plate sulphuret of lead, that seemed to have sunk to the bottom by its specific gravity. All these circumstances seem to point to a projection of this metallic and mineral matter from below.* At these mines, when circumstances are favorable, they can raise and bring to the surface, as I was informed, five thousand pounds of the mineral a day-a quantity that could be easily quadrupled if the demand for the metal justified it. This sulphuret yields sixty-five per cent. pure lead of cominerce. I had occasion to observe, in numerous instances, that the mineral indications on the public lands were quite as encouraging as at the established mines; but this mineral of lead, to judge from obvious appearances, exists in such inconceivable profusion in the metalliferous region of the south of Missouri and the north of Arkansas, that, like the iron of which I am about to speak, it may be relied on for countless ages as a source of national wealth, and an in| terminable supply of the most useful metals.

Having completed my examinations of the lead mines, I pursued a southerly course, with the intention of visiting the district of primitive rocks, as it had been described to me, which lies on about the same parallel with the heads of the Merrimack river. At a considerable distance I perceived very lofty hills of a different aspect from any I had yet crossed, and having an abrupt and stony ascent. The rocks upon the slope of the chain are for a considerable distance denuded, and present a well defined syenite. The chain at a distance appears to run N. E. and S. W., but, upon crossing it, and examining it inside, it deflected into a crateri-form, reminding me, in some of its features, of some ancient volcanoes I had seen. In various portions of this district I found varieties of greenstone, alternating with some horizontal rocks entirely quartzose, and containing no lime. Upon one lofty hill of syenite I found immense breadths of this siliceous rock, extremely and ponderously impregnated with iron; and at a distance of about a mile from this, the iron increasing in quantity in the intermediate distance, I came upon one of the rarest natural metallic spectacles I have ever seen. Upon a mound sparingly covered with trees, I observed a veinlike mass of submagnetic iron, and having a bright metallic fracture, of a steel gray color. This vein was about one hundred and fifty feet above the surface of the adjacent plain, and at the surface had the appearance of being roughly paved with black pebbles of iron, from one to twenty pounds weight; beneath the surface it appeared to be a solid mass. I measured the vein from east to west full five hundred feet, and I traced it north and south one thousand nine hundred feet, until it was covered with the superficial soil. Unusual as is the magnitude of the superficial cublic contents of this vein, yet it must be insignificant to the subterranean quantity. This extraordisingle locality of iron offering all the resources of Sweden, and of which it was impossible to estimate the value by any other terms than those adequate to all a nation's wants.† Upon a inore minute investigation of the country, I found other similar metallic beds, though not of an equal extent, and all upon the public lands.

In pursuing the main horizontal vein, I came, in succession, to a great number of cavities or pockets-analogous to those of some parts of the gold region in Virginiain the calcareo siliceous rock, of various sizes. Some of these caves, as they are there called, are not more than four or five feet across, whilst others are much more extensive. I examined one which was about forty feet from top to bottom, and about thirty-five feet in diameter. The uniform horizontality of the veins would keep the true nature of their origin in great obscurity; but, before I reascended, I had an opportunity of examining what they called the main channel, which proved to be an almost vertical vein, filled with compact galena, and about eighteen inches broad, I found the course of this lode to be about N. N. E. and S. S. W., with an inclination of about 18°; and upon examining it further, and reviewing what I had seen before, I had no longer any difficulty in understanding that these horizontal veins, and their sub-nary phenomenon filled me with adiniration. Here was a ordinate ones, were lateral jets from the main lode, after the manner that Mr. McCulloch has described the structure of the horizontal injections of trap rock into sandstone at Trotternish, in Scotland. Having made these observations upon the direction of these veins, I commenced an examination of their structure more in detail, and found they were all what is called in some of the mining districts of England wet veins, being, without exception, encased, not in sulphate or barytes, but in pure bright red argillaceous matter, quite wet below, and cutting with a bright waxy face. This red clay accompanies the galena wherever it goes, always including it as in a sheath, and carrying along with it sometimes nodules of quartz, and of iron, zinc, and galena, which last compound is called by the miners dry bones. Every one of the pockets or cavities was filled with this red clay, even

* Vide McCulloch's "Western Highlands of Scotland."

This syenitic chain comes up through the calcareo-siliceous beds of the country, extends for several miles, and stands separated from all other intrusive rocks, as far as my investigations permitted me to observe: some parts of it are traversed by veins of trap, none, which came under my observation, exceeding a breadth of two inches. At present, I am disposed to believe that it is an independent

During the eruption off Sicily, in 1832, when the volcanic island was formed, the agitated ocean was filled for several weeks with red

mud.

It yields about sixty-five per cent. of fine iron, but is found not t weld easily, which I attribute to an excess of sulphur.

Geological Reconnoissance.

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mass of intrusive matter, which has been erupted in the most remote periods, and I leave it to future philosophical observers to decide whether it is cotemporaneous with the injection of the metallic veins which I have described. is highly probable that the shattered veins which have been before spoken of, and their parts left in different positions on their edges, have been rendered so by accidents posterior to their origin. The proximate causes do not require to be looked for at a great distance; the neighboring intrusive masses of syenite announce subterranean operations of great magnitude to have been at some period at work, and we have evidence that the adjacent country is occasionally subjected to volcanic action, perhaps attended with electric power of great extent, from the violent concussions to which it was subjected in 1812, when New Madrid and its vicinity, and the neighboring country to a considerable distance, were so agitated. Upon that occasion, extensive districts were raised and depressed, old lakes were choked up, and new ones formed. New Madrid is not one hundred miles from these shattered veins the influence of the earthquake of 1812 was felt in their vicinity; and we can easily conceive of an electric force passing through these veins at some other period, and bringing them into the disrupted situation in which we now find them.

As I advanced to the south, the country bore the appearance of being still more pregnant with metallic matter; it became very hilly, the elevations at various points exceeding perhaps two thousand feet from the level of the sea. It was a succession of lofty hills and deep glens, of an arid, petro-siliceous character. Nothing was to be seen but nodules of flint and hornstone, masses of mammillary quartz and siliceous gravels, with not unfrequent traces of copper. Quartzose and siliceous matter seemed to have universal dominion; and so incoherent and anomalous were the mineral appearances occasionally, that if I had not traced the formations from the Mississippi, and kept a steady eye upon them, it would have been impossible for me to suspect that I was walking over the equivalents of the carboniferous Limestone. Yet this was the fact; for, on descending into some of the deep glens, where there was a prospect of finding the rocks denuded, it often occurred to me to find regularly stratified beds of limestone and quartzose sandstone underlying amorphous masses of petro-siliceous matter; whilst mammillary quartz, nodules of opaque flint in concentric circles, and compact sulphate of barytes, were strewed around, with fragments of sulphuret of lead profusely lying about where furrows had been made by the rain. I crossed some lofty hills of massive dark reddish greenstone, lying in a course about southwest from the syenitic chain. On the flanks of some of those hills I found other extensive deposites of submagnetic iron, and frequently oxide of manganese, which the hunters call black tin. Zinc also is not uncominonly met with; and nothing is more general, especially in the fluviatile deposites near the streams, than profuse quantities of bog-ore and red oxide of iron.* This is especially the case with the deposites of the river St. Francis and its tributaries.

It would be but to repeat these incidents, to detail, in a minute inanner, my progress to White river, in the Territory of Arkansas. The country presents a continual change of level, a never-ending succession of hills and valleys. From a remarkable eminence in Wayne, the most southern county in the State of Missouri, I enjoyed a singularly splendid view; numerous lofty ridges were seen running parallel to each other to the north and northwest. That upon which I stood, could not fall far short of three thousand feet from the level of the ocean, was not more than one hundred feet broad, and had a semicircular form, which imparted a crater-like appearance to the deep and gloomy glen beneath. This was as savage as the wildest nature

I have heard, from good authority, that cobalt has been found in Missouri.

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could make it, and possessed a fearful, yet attractive character. The extent and grandeur of the view, the silence and solitude of the scene, were impressive; no birds were present, and it was uninhabited by wild beasts, for the country was of such an arid, siliceous nature, that there was neither water nor herbage, both necessary to the smaller animals, which are the immediate motives that lead the rapacious ones to prowl about.

The summits of all these ridges have the petro siliceous character before described, and the calcereous beds are very commonly found in the ravines; occasionally, however, some of the regular beds are quartzose; and upon one occasion I found the oolitic beds of the carboniferous limestone, which I had recognised in the Cumberland mountain near Sparta, in Tennessee, and subsequently in Kentucky, entirely silicified, with the ovula unimpaired by the change-a fact in geology as important as it is rare, sincs it shows the influence which siliceous solutions have had at some remote period, not only upon organic remains, but upon the calcareous rocks in which they are imbedded. From the preceding geological circumstances of the parallelism of these petro-siliceous ridges, and the almost uniform presentation of the calcareous beds in the valleys, I am led to class these valleys amongst those which have been called valleys of denudation, considering the country to have been at one time continuous as to elevation, and that the valleys have been scooped out by the agency of waters, at some period when the ocean has retreated from this part of the country-an operation to which I have for a long time been led to attribute the peculiar structure of some of the Alleghany ridges.

After leaving the waters of the St. Francis, I had to cross those streams which are tributary to Big Black riverstreams of great beauty, all rising in a siliceous country, and so extremely transparent that it is almost impossible to take the fine fish they contain, at their greatest depths, by daylight. These streams all run through alluvial bottoms of various dimensions and of great fertility; but at their confluence with Big Black river, an immense breadth of alluvial soil commences, which extends southeast to the Mississippi, enclosing vast swamps of deciduous cypress, but, with these, extensive rich bottoms of land eminently fitted for the culture of cotton and maize, and capable of sustaining a great population. These public lands, which, for a great extent of country, are subject to inundation from the back water of the large streams, could-as far as the information I received from persons acquainted with their situation is a warrant for my opinion-be in a great measure reclaimed by constructing levées at particular points. A present, owing to their liability to inundation, they are only known to the hunter who frequents the geographical line which separates Missouri from Arkansas, east of Big Black river, where herds of buffalo and elk still roam. Whilst I was in that neighborhood, I repeatedly heard of the buffalo, and saw the hide of a large elk which had been shot out of a herd by a hunter the day before. These are supposed to be the only remains of the buffalo and elk, which have lingered near the Mississippi, in a district where man has not yet permanently occupied the country.

Some of the tributaries of Big Black river, such as the Currant and Eleven point rivers, which disembogue in the Territory of Arkansas, rise far to the west, in the high petro-siliceous elevations before described. The following fact, as illustrative of the economy of nature, is interesting, and was so consant in its occurrence that at length I came to confide in it as a geological indication. Wherever these streams, towards their heads, had passed over nothing but siliceous minerals, and where calcareous matter was comparatively scarce, I found that those varieties of the fresh water shells belonging to the genus unio, which have been considered by some very zealous conchologists as distinct

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species, were all wanting, except a few, which conformed in their external appearance to those simple types found in the Atlantic streams of the United States; those, for instance, which are found in the Schuylkill, in Pennsylvania, and in the Rappahannock, in Virginia. Whereas, where those streams had penetrated deeply into the hills, amongst the calcareous beds, or had risen almost amongst the calcareous beds at the eastern slopings of the highlands, as the Strawberry river does, I found a very great number of those beautiful varieties which abound in the Cumberland and Ohio rivers, and most of the streams running through the carboniferous limestone of the country west of the Alleghany ridges.*

and from an eminence about forty miles from the Arkansas river, I had a grand view of a perfectly flat wilderness, about ten miles broad, terminated by lofty ridges running east and west. There was not a patch within the horizontal bounds that indicated a settlement; nothing but a dense forest, containing, as I had been informed, and as I afterwards found, no water, except a few putrid pools in the bottoms of the bayous. In this grand picture of the wildest American scenery, there was nothing to break the comprehensive and uniform woody character, but an immense conflagration that was raging in the distance, in my line of advance, and from which rose a dense volume of smoke. Fires of this kind are often occasioned by the inadvertence of hunters, and sometimes purposely to drive game in particular directions. I had often passed through many miles of fired land, where the smoke not only obscured every thing around, but where it was a painful effort to resist the inconvenience it occasioned. On extricating myself from this arid plain, I reached a ridge with an elevation of about 70°, and here I perceived the geological formations were changed; the rocks had become highly inclined; the sandstone had become much intermixed with narrow seams of quartz, which was not compact, but consisted of fibrous bundles of imperfect crystals closely wedged in upon one another. Subsequently, pursuing a southerly direction, I crossed, within a distance of eight miles, four abrupt ridges, running east and west, consisting of highly inclined reddish ferruginous sandstone, intersected by seams of quartz; and, examining the country around with greater diligence, I found that the sandstone during the remaining part of my progress to the banks of the Arkansas, to verify this observation, and to satisfy myself that I was upon the true equivalent of the old red sandstone and grauwacke of English geologists. In various situations I found the old red sandstone formation exceedingly broken up, and the fragments piled up, as it were, in great masses. There are some singular instances of this within three miles of Little Rock, on the north side of the Arkansas river.

In descending the southern slopes of these petro-siliceous highlands, I came upon the valley of White river, in Arkansas, which in some places is very broad, and cuts those highlands into two distinct portions. This stream, which is very little known in the Atlantic States, is one of the most important and beautiful rivers in the United States. It takes its rise in the western edge of that elevated country which has received the designation of Ozark mountains, and, receiving several important tributaries, some of which take their rise north of the thirty-seventh degree of north latitude, pursues its course for seven or eight hundred miles of serpentine windings to its mouth, south of the thirty-fourth degree of north latitude, watering that fine agricultural country, amongst the most charming portions of the Territory of Arkansas, which is comprehended in the county of Washington, and, pursuing a general easterly course to its great tributary, Big Black river, near which, having reached the confines of the high-rested upon grauwacke slate. I had many opportunities, lands, it deflects to the south to mingle its waters with the Mississippi. This latter portion of its course lies through the richest alluvial lands, with excellent steam navigation the whole distance from its mouth to that of Big Black river, and showing an evident practicability of being made navigable still further towards its sources, two hundred miles to the westward. Big Black river itself might be made navigable for a great distance, and without much expense: if the willows and aquatic shrubbery, which impend over its banks in those parts where it is narrow, were only removed, it would be perfectly accessible to steamboats. I have deemed it proper to make these observations, because simple improvements of this kind would lead navigation into the vicinity of those invaluable mineral deposites which I have before described, and which, until something is done of this kind, must remain inactive, together with many other mineral substances both in Arkansas and Missouri, especially marbles and stones of construction.

Having traversed the valley of White river, I again ascended the formations I had been so long upon, and with the same indications wherever I went, Here again I found the horizontal limestone, overlaid by quartzose sandstone and petro-siliceous knolls, but always without organic remains; it would almost seem that the waters, which deposited these beds, were too hot to admit of animal life. Having crossed Little Red river, one of the tributaries of White river, and the source and direction of which are south of this last, and proceeded some distance south, I perceived a coming change in the geological formations. The sandstone became exceedingly ferruginous;

[blocks in formation]

The advance to Little Rock, in this direction, is over two miles of alluvial soil, perfectly flat, and the extremely steep bank of the river, during low water, shows on the north side no rocky structure whatever; but on the south side the grauwacke slate crops out very boldly on the bank, and, being the first stony substance met with ascending from the mouth of the Arkansas river, has given its name of Little Rock to the present seat of Government of the Territory of Arkansas.

The grauwacke slate here is highly inclined, and dipping S. E. is traversed by very broad bands of quartz; no red sandstone is superimposed upon it at the river, but at a very limited locality on the bank I found a calcareous dedeposite containing marine fossil shells belonging to the tertiary beds. Three miles west from Little Rock, this deposite reappears in considerable quantities, and is quarried for the purpose of making lime. A few miles distant from the seat of Government, the old red sandstone is almost replaced by quartz, especially to the northwest, in the direction of the Great Mammelle river. At a distance of five miles from the town, the ridges of old red sandstone occur again, running about east and west. The Mammelle mountain, distant about eighteen miles from Little Rock, is an outlier of the same formation: the southwest aspect of this cone is very imposing, and bears a strong resemblance to a pyramid; on approaching it, the whole facade presented a lofty mural escarpment, about seven hundred feet above the level of Arkansas river, according to the computation I was able to make, with a broad talus at The southwest edge of this pyramid showed

the bottom.

* Ostrea, turritela, calyptrea, cerithium, &c.

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