Scenes and Adventures in the Semi-Alpine Region of the Ozark Mountains of Missouri and Arkansas Part 27

Zinc is abundant, but as the ore is the sulphuret, it is not very valuable. It is not mentioned that calamine, which is the useful ore of zinc, has been found.

As to the geological nature of the country, in which the lead mines are situate, he informs us that "Bellevue abounds in granite;" that the only vein of granite rock in the mine country (as far as he had opportunity to observe) pa.s.ses across the south-western end of Madison county--runs into Bellevue--is four or five miles wide, and twenty or thirty miles in a direction from south-east to north-west.

The granite is spoken of in another place, (p. 170,) as being a geological phenomenon, as containing imbedded in it or lying upon its surface, gneiss, green stone, porphyry, iron ores, &c.; it is spoken of as a red granite, containing very little mica, and as being used for millstones. It is mentioned as the "only ma.s.s of granite known to exist between the primitive ranges of the Alleghany and Rocky mountains," and as being surrounded on all sides, and to an almost immeasurable extent, with secondary limestone.

Again, (p. 193,) the granite is cited as the "old red granite in mountain ma.s.ses, with some veins of green stone, green stone porphyry, and gneiss;" it is said to terminate in very rough and broken high lands. At page 213, it is mentioned, still again, as giving origin to the river St. Francis, whose "springs gush out among these stupendous piles of red granite." Besides the ores of iron, lead and zinc, "quartz, feldspar, shorl, mica, and graphite are among the minerals furnished by that region," and "green stone, gneiss, and green stone porphyry, are among the larger ma.s.ses of rock." The green stone, it seems, "is found in large isolated fragments, lying promiscuously among the fragments of granite which have tumbled down from the lofty cliffs above, and is rendered porphyritic by crystals of green and flesh-colored feldspar."

We have no right to doubt that the rock described is granite, as the princ.i.p.al features delineated, correspond with that supposition. As it is described as being solitary, the only granite between the Alleghanies and the Rocky mountains, we are led to ask, is it a portion of the nucleus of our globe, covered on every side, for many hundred miles, with secondary rocks, and here heaving its head through the superinc.u.mbent strata, and standing alone? But what are we to conclude of the limestone? We should have liked especially to have had the relations of this limestone with that remarkable granite region pointed out. Does this latter repose on the granite, where it dips obliquely under, as it probably does, in order to find its way beneath the other rocks, and to vindicate its claim to a fundamental position? But, perhaps we are asking more than is reasonable, for, it may be that there are no such sections in the strata as would expose all these facts to view, and enable the observer to decide.

These hints we have dropped, not, we trust, from a captious disposition, but because we have found a real difficulty in conceiving clearly of the geological nature of this limestone, which, it seems, is the basis of the lead-mine country, and therefore it is very important that its characters should be indubitably fixed. We have not been so fortunate as to see Mr. Schoolcraft's specimens; possibly a view of them would have rendered the preceding remarks, in part at least, unnecessary.

Leaving the geological features of the lead-mine district, we proceed to cite some interesting and important facts from Mr. Schoolcraft's work:--"The soil," he remarks, "is a reddish colored clay, stiff and hard, and full of fragments of flinty stone, quartz and gravel; this extends to the depth of from ten to twenty feet, and is bottomed on limestone rock. It is so compact in some places as almost to resist the pick-axe; in others it seems to partake of marl, is less gravelly, and readily penetrated. The country is particularly characterized by quartz, which is strewed in detached pieces over the surface of the ground, and is also found imbedded in the soil at all depths. This is here called blossom of lead. Iron ores and pyrites are also scattered over the surface of the ground, and occasionally lead ore. The mineral productions of the country, in addition to lead, are zinc, iron, ochre, red chalk, saltpetre, sulphur, alum and salt."

The ore (the author remarks) is the lead glance, galena, or sulphuret of lead. It is very rich and beautiful, and specimens in our possession fully confirm Mr. Schoolcraft's account; they have a very broad and perfectly foliated fracture, and a high degree of metallic l.u.s.tre; they break in cubical fragments, and the minutest portions still retain this form.

We have already observed that large fragments are found loose in the earth: they sometimes weigh four or five pounds; we have such specimens from these mines; they are of a cubical form, and are surrounded, except where they have been broken, by an earthy incrustation.

It is observed that the marly earth thrown out from the pits, enriches the ground, so that in a few years it is covered with a very rank growth of trees, vines, &c., and this is a regular characteristic of old diggings. Innumerable portions of radiated quartz, and sharp fragments of flinty stones are mixed with the clay, and form the first stratum of about fourteen inches. The next is of a red clay, and is four or five feet thick, and less mixed with similar siliceous substances. Then comes a layer of gravel and rounded siliceous pebbles, about one foot thick, containing small portions of lead ore. The thickness of the bed of ore is generally a foot; and the lumps of ore appear to have been rounded by attrition, like common gravel. "This is the character of what is called the gravel ore, and no spars are found accompanying it. The greatest proportion of lead ore is, however, found imbedded in, and accompanied by, the sulphate of barytes, resting in a thick stratum of marly clay, bottomed on limestone rock." They invariably arrive at the rock at the depth of from fifteen to twenty, or sometimes thirty feet; a new process by boring and blasting is now necessary, and most diggers abandon their pits rather than prosecute them at this expense. If, however, as there can be little doubt, the limestone is the real matrix of the lead ore, the time will come when the present diggings will be considered as merely superficial beginnings, and the work will be resumed where hitherto it has been abandoned. It seems that the almost invariable practice of the miners is, to persevere till they strike the rock, and then to go and dig elsewhere; they cannot, if disposed, prosecute the business by levels or galleries, for they are not permitted to carry on their mining except immediately under the surface that is covered by their respective leases, or by twelve feet square, which, if unoccupied, an adventurer may cover by occupancy. Among the substances accompanying the lead, blende and the sulphate of barytes are said to be very abundant; the latter in specimens which we have, is particularly brilliant and white;[24] the quartz is often prettily crystallized, and is so invariable a concomitant of the ore, that the miners, as we have before remarked, give it the meaning appellation of mineral blossom.

A curious fact is mentioned by Mr. Schoolcraft, respecting the Elliott's mines. "During the remarkable earthquakes of 1812, a fine spring of water at the mouth of the mines suddenly became warm and foul, and in a few days dried up entirely, and no water has run there since."

"Illuminations in the atmosphere are frequently observed in this vicinity on the approach of night."[25]

It seems there is a considerable quant.i.ty of a greyish white sublimate collected at the log hearth furnaces, and rejected by the workmen upon the supposition that it is sulphur and a.r.s.enic; but Mr. Schoolcraft, by unquestionable experiments, ascertained that it was lead, as would appear, in the form of a carbonated oxide. A considerable loss is in this manner sustained, and in a more advanced state of the metallurgic operations of these mines, the author's valuable suggestions will not be neglected. There is one mine (M'Kain's) where the ore is of the steel-grained variety--it is said to yield less lead, and is inferred to contain more silver than the common ores; we are aware that this is the common impression, but our own experiments on different varieties of lead ore would induce us to think that it cannot be relied upon. We have examined fine steel-grained ore which contained very little silver; in one specimen only one five-thousandth part, and in another, and that a foliated specimen, we found three and a half per cent, of silver.

The methods of digging for the ore are sufficiently simple. "A pick-axe and shovel are the only tools used for removing the earth, and the drill, hammer and priming rod are added when it is necessary to blast."

The process is carried on as in digging a common well.

We must refer our readers to the book itself for a clear account of the furnaces and furnace operations, employed for smelting the lead; it will be the more intelligible, as it is accompanied by two good plates containing views and sections of the furnaces. A circ.u.mstance which appears very extraordinary is, that the furnaces are most commonly built of limestone, which is of course calcined, and brought to the condition of quicklime by a few blasts, and then it crumbles and the furnaces must be rebuilt.

The ore yields at first fifty per cent., and then the ashes give fifteen per cent, more--sixty-five[26] in the whole.[27]

Custom, says the author, has established a number of laws among the miners, with regard to digging, which have a tendency to prevent disputes. Whenever a discovery is made, the person claiming it is ent.i.tled to claim the ground for twenty-five feet, in every direction from his pit, giving him fifty feet square. Other diggers are each ent.i.tled to twelve feet square, which is just enough to sink a pit, and afford room for throwing out the earth. Each one measures and stakes off his ground; and though he should not begin his work for several days afterwards, no person will intrude upon it. On this spot he digs down, but is not allowed to run drifts horizontally, so as to break into or undermine the pits of others. If appearances are unpromising, or he strikes the rock, and chooses to abandon his pit, he can go on any unoccupied ground, and, observing the same precautions, begin anew. In such a case, the abandoned pit may be occupied by any other person; and sometimes large bodies of ore are found by the second occupant, by a little work, which would have richly rewarded the labors of the first had he persevered.

Mr. Schoolcraft, from various particulars, infers that the average annual produce of the Missouri lead mines, as mentioned before, is three million pounds per annum, and the lead was worth in 1819, at the mines, four cents per pound. For the last three years, up to 1819 inclusive, the produce of the mines was estimated at three million seven hundred twenty-six thousand six hundred and sixty-six pounds per annum of pig lead, which the author supposes to be not more than one half what the mines are capable of yielding.

The number of miners is between eleven and twelve hundred, and the number of hands employed in labor at different mines is from twenty to two hundred and forty, including in both cases persons of all descriptions.

Many miscellaneous topics connected with the general subject of his work, are introduced by Mr. Schoolcraft, such as the sections relating to the manufactures, and uses of lead, &c., but it is not our object to advert to these topics.

Among the miscellaneous mineral productions of the western regions, there are some that are interesting; and it will be seen from the author's table of minerals, that the list is various. There are several caverns which produce nitrate of potash by the usual treatment; and Ashley's Cave, about eighty miles from Potosi, is said to be one of stupendous size, and to "afford native nitrate of potash in beautiful white crystals."

The novaculite is mentioned as occurring on Was.h.i.+ta, as described by Mr.

Bringier in the present number.

Steat.i.te exists in abundance at the falls of St. Anthony, on the Mississippi, and is used by the Indians for pipes.

The fluate of lime, near Shawneetown, was described in the first volume of this journal.

Among other minerals, Mr. Schoolcraft mentions chalcedony in several varieties, earthy oxide of lead, native copper, alum, manganese, opalized and agatized wood, opal, jasper, coal, gypsum, native epsom salts, pumice stone, agate, onyx, burr millstone, native iron, &c.; for the localities and descriptions of which, we must refer to the book itself.

Those facts of Mr. Schoolcraft's volume which relate to statistical and political topics, do not come within the plan of these remarks.

During our cursory notice of this work, we have cited a number of the most prominent facts which it contains, both because they are in themselves important, and because we were willing to call the attention of our readers both to them, and to the volume in which they are contained. Both are, in our view, ent.i.tled to great respect; and we confess ourselves very much indebted to Mr. Schoolcraft for a great ma.s.s of valuable information, which, in a connected form, is, we believe, nowhere else to be found. His statements (as regards the most valuable part) are drawn from his own research and observations, and have evidently been the result of much effort, and of no small share of fatigue and personal privation. We trust that so valuable a work will not stop with a single edition, and perhaps we might venture to suggest to the author, that in a second, he might advantageously condense into one view some facts which are several times repeated in different parts of the volume--such as those respecting the granite and its connected rocks, the lead ore and its a.s.sociated minerals, &c.

We consider the present work as an acquisition to our means of information respecting our mineral resources, and believe that it must be a regular volume of reference for all those who are interested in the investigation of these subjects.

FOOTNOTES:

[24] It is mentioned by the author, as a chemical test or reagent: it may, by decomposing it by ignition with charcoal, or with an alkaline carbonate, be made to afford its earth for the preparation of barytic tests, but we are not aware that it is itself ever used as a test.

[25] They are attributed by the author to phosphorus. Is it supposed to be in the form of phosphuretted hydrogen? May not these be electrical phenomena?

[26] According to Dr. Meade, the Missouri ore affords only a trace of silver. (See Bruce's Minl. Journal, vol. 1, p. 10.)

[27] Mr. Schoolcraft thinks it may yield seventy per cent.--it gave him by a.n.a.lysis eighty-two per cent.

THE END.