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portion of the district induce me to believe that iron ore can be found there, on the surface alone, sufficient to supply several iron furnaces for years to come. In relation to the Magnetic Iron Beds of the Penokie Range, bordering on Lake Superior, he says: “The most easterly appearance of magnetic iron which I observed, was in fissile black slate, about four miles west of the Montreal Trail, along which the Section No. 4, W. is made. About four miles along the strike of the beds, southwest by west, the bed was seen by Mr. Randall, in 1848, in the Fourth Principal Meridian, Township 44° north, eighteen miles from the lake. We may with confidence pronounce it to be a continuous bed from the meridian westward to Lac des Anglais. Its thickness, richness, and value, vary very much; but we found it more or less developed, whenever we crossed the range, and could get a view of the rock. The bed of magnetic iron ore south of Lac des Anglais is of extraordinary thickness-twenty-five to sixty feet. The proportion of iron and quartz is very variable, but the separation of them by mechanical means would, in general, not be difficult. There are many places in the mountain, west of Bad river, which present more than fifty feet of quartz and iron, in about equal proportions. It should, however, be borne in mind, that the whole region is not only covered so thickly with timber that no distant views can be had without climbing trees, but the drift often conceals the rocks, over a large proportion, even of the elevated ridges. Where the west branch of Tyler's Fork crosses the chain, Mr. Beesley found the southerly face of the uplifts well charged with a rich, heavy ore, showing thirty, fifty, and seventy feet, with iron predominating over quartz. All the specimens we saw were of the black
magnetic oxide, without any of the red. The productive yield
1 These ores of iron yield from 40 to 60 per cent. of the metal.
of such an ore can only be determined by trial, in properly constructed furnaces; but judging of our specimens by weight, they will afford fifty to sixty per cent. of the metal. The analysis of one specimen yielded over sixty-six per cent. For present use a supply of ore may be obtained from the rubbish, at the foot of the uplifts, in blocks and pieces, already detached from the cliff, and the accompanying quartz. Where it is not dislodged, it will be necessary to break the whole, and then assort it. There are cases where numerous particles of the oxides, both red and black (the protoxide and the peroxide), are disseminated through the quartz rock, above and below the regular beds. This might be separated by bruising and stamping
a process which the whole must undergo, in order to be lirofitably wrought in the forges.
“There is no limestone yet known in the region to be used as a flux; but there is an abundance of timber and water-power. There are certain proportions of iron and silex, and of silex and magnesia, that are easily fused. If the silex of this ore is not so excessive as to make it refractory — or, if in practice, that difficulty can be remedied by the use of magnesian slates, which are abundantthese mines may be wrought hereafter at a profit, and rival the works of Northern Europe. The magnetic ores of the northern part of the State of New York, that have produced iron famous for its strength, are also siliceous. The magnetic iron-ore is freed of a portion of its silex, at little expense, after being bruised, by the application of magnets acting on a large scale upon the magnetic particles. The part which enters chemically into the ore, forming a silicate, is not wholly cleared by working, but gives a very fine-grained metal, that is peculiarly good for steel. The · famous Swedish iron is from beds of magnetic ore, embraced
in hornblende rocks, doubtless metamorphic, and analogous to those of Bad River.
“The extensive mines, or rather mountains, of iron-ore in Michigan, are also magnetic, and associated with metamorphic slates. These ores are, in some cases, more inclined to the peroxide than the Bad River beds; but specimens from the two regions are often, so similar, that no one would be able to separate them, by the texture, color, or weight. The geological associations are precisely alike. In Michigan, as in Wisconsin, the mountains composed of tilted magnesian, hornblende, and siliceous slates, enclose beds of ore. There, as here, on each side of the metamorphic range, are igneous rocks, of various ages and composition - quartzose, granitic, syenitic, and trappous. The ores of that region have attracted attention, and one establishment for making blooms, direct from the ore, has been in operation more than a year. The iron is remarkable for its solidity and toughness, keeping its place better than Swedish, and is no more brittle. It possesses the quality of being worked into fine cold-drawn wire, and has been sought after by an establishment for manufacturing wire in Massachusetts.
“ The Iron Ridge, and Ore Beds of Dodge County, have attracted much notice of late years, partly on account of the interesting and anomalous character of the ore, and partly because of the great practical value of a bed thus situated. The 'Wisconsin Iron Company' has the credit of making the first experiment upon this ore, and, in fact, of erecting the first stack furnace in Wisconsin. Their works at Maysville, in Dodge County, are driven by water, and consume the ore of the 'Iron Ridge,' which is hauled on sleds, in winter, about four and a half miles. The analysis of the ore taken from Mr. Theodore B. Sterling's saw-mill, Section 13, T. 11, north range, 16° east of the
4th Principal Meridian, the course being east and west, as given by Professor Cassels, of the Medical College at Cleveland, Ohio, indicates over 53 per cent. of iron."
The richness of the iron veins in this district, and along the Lake Superior shores, cannot be correctly known, until more mines are opened. But more encouraging and numerous surface-indications of an abundant supply of this useful metal can hardly offer themselves to the notice of the geologist. In a country more thickly settled, and with skill and capital to spare, these would speedily cause and justify the employment of whole villages of workmen. To incidental causes alone, and not to any natural deficiency of material, must be attributed the custom of importing annually from England, into this country, millions of dollars' worth of iron for railroads and other purposes. Enormous as is the produce of Great Britain's iron-furnaces, we might rival it in America. How little, here in the West at least, we have hitherto improved our natural resources in this branch of commerce, is proved by the thousands of tons of rich iron-ore which lie unappropriated and uselessly scattered over the State of Wisconsin.
But this is not only the worst feature of neglect. Strange as it may seem, the iron rails laid upon the road to Fond du Lac, (the nearest route to these mines,) were brought from England, not only across the Atlantic, but twelve hundred miles into the interior, and within two hundred miles from these rich iron mines, – mines as rich, as productive, and as easily worked, as those in England, from which these rails are manufactured and shipped so far, and at such enormous and unnecessary expense, and this, too, besides the government duties paid. This is infinitely more absurd than the importing of bricks from Holland, by the early settlers of New York and Albany, and more than it would be to bring lumber from Europe to build
houses in the very shadows of the extensive Wisconsin pineries. This iron is of a superior quality, and can be worked and furnished along the railway lines at one-half the cost of foreign iron. The ore is unsurpassed in richness and purity, and can be transported wherever there is coal, and there manufactured.'
Facts, such as these, call loudly upon Government for additional acts of legislation. If English iron of an inferior quality is allowed to enter our country, and successfully compete with the products of our own mines, sufficient duties should be levied upon it to protect us from ruinous competition with their large capitalists, who, by the low wages they allow their half-starved workmen, can afford to sell their iron, even with the present low duties, at the same rates as ours can be afforded at the mines.
In relation to building-stone, Dr. Owen remarks : “I was, for a time, in doubt in regard to the value of the Wisconsin limestone as a building material. Much of the limestone that is taken from the diggins' crumbles, also, on being exposed to the weather; yet a portion of the formation will yield some of the best quarries in the world, and several excellent ones are already opened. For example, on the Sinsinnewa Mound, at Mineral Point, at the Four Lakes, and (but not so good) on the Peccatonica. This excellent building-stone chiefly occurs in the lower portion of the upper beds of the cliff limestone, and also in the lower beds of the Missouri limestone. It is of a beautiful, uniform, light-yellow color-compact, finegrained, sharp-angled, capable of receiving a handsome finish, and, if well selected, calculated to endure for ages uninjured. It is very readily quarried in square blocks, from six inches to a foot in thickness; can be obtained, however, doule or treble that thickness, and of any required
Report of Committee on Public Lands, May, 1856.