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abolished, and in 1869 the fee constituting one a life member was raised to twenty dollars. The first annual fair of the society was held in Janesville, in October, 1851 Fairs have been held annually since, except during the years 1861, 1862 and 1863. In 1851 premiums were paid to the amount of only $140, while at the present time they amount to nearly $10,000. In 1851 there were five life members. At the present time there are over seven hundred, representing all the various industries of the state. The fairs held under the auspices of this society have been of excellent character, and have been fruitful of good to all the industries of the state, but more especially to the farmers. The state has been generous in aid of this society, having furnished commodious rooms for its use in the capitol building, printed the annual report of the secretary, a volume of about 500 pages, and donated annually, for many years, $2,000 toward its support. Besides its annual fairs, for the past five years there has been held an annual convention, under the auspices of this society, for the reading and discussing of papers upon topics of interest to farmers, and for a general interchange of ideas relating to farming. These conventions are held in high esteem by the better class of farmers, and have added greatly to the usefulness of the society. The "Wisconsin State Horticultural Society" was originally the "Wisconsin State Fruit Growers' Association," which was organized in December, 1853, at Whitewater. avowed object was "the collecting, arranging, and disseminating facts interesting to those engaged in the culture of fruits, and to embody for their use the results of the practice and experiments of fruit growers in all parts of the state." Exhibitions and conventions of the association were held annually up to 1860, after which the society was disorganized, owing to the breaking out of the war of the rebellion A volume of "Transactions" was published by the association in 1855. In 1859 its transactions were published with those of the state agricultural society. From 1860 to 1865 no state horticultural association was in existence. In September of the latter year the "Wisconsin Fruit Growers' Association" was reorganized as the “Wisconsin State Horticultural Society." The legislature had previously provided for the publication of the proceedings of such a society, in connection with those of the State Agricultural Society. The new society has held annual exhibitions, usually in connection with those of the State Agricultural Society, and annual conventions for the reading of papers upon, and the discussion of, horticultural subjects. In 1871 an act was passed by the legislature incorporating the society, and providing for the separate printing of 2,000 copies annually of its transactions, of which there are now seven volumes. The most active, intelligent, and persevering of the horticulturists of the state are members of this association, and to their careful observation, to their enthusiasm and determined persistence in seeking means to overcome great natural difficulties, the state is largely indebted for the success already attained in horticulture. Besides these state associations, there are many local agricultural and horticultural societies, all of which have been useful in aiding the cause for whieh they were organized. Farmers' clubs and granges of the "Patrons of Husbandry" have also done much, both directly and indirectly, to promote the industrial interests of the state. frequent meetings, at which discussions are held, views compared, and experiences related, much valuable intelligence is gained, thought is stimulated, and the profession of farming advanced. As agriculture, like all kindred professions, depends upon intelligence to direct its advancement, all means intended to stimulate thought among farmers will, if wisely directed, aid in advancing this most complex of all industries. To those above named, and to other like associations, is in a large degree to be attributed the present favorable condition of the agriculture of the state.

Wisconsin is yet, comparatively, a new State. It was mainly settled by men who had little moneyed capital. Markets were distant, and means of transportation poor. The early settlers had consequently to struggle for a livelihood in the face of the greatest difficulties. When these opposirg

circumstances are taken into account, and the improvement in methods of culture, and changes from grain to stock and dairy-farming that are now being made, are given their due weight, it must be acknowledged that the present condition of the agriculture of the state is excellent, and that the future of this most important industry is rich in promise of a steady, healthful growth, toward a completer development of all the agricultural resources of the state.

MINERAL RESOURCES.

BY ROLAND D. IRVING, PROFESSOR OF GEOLOGY, ETC., AT THE UNIVERSITY OF WISCONSIN.

The useful mineral materials that occur within the limits of the state of Wisconsin, come under both of the two grand classes of such substances: the metallic ores, from which the metals ordinarily used in the arts are extracted; and the non-metallic substances, which are used in the arts for the most part without any preliminary treatment, or at least undergo only a very partial alteration before being utilized. Of the first class are found in Wisconsin the ores of lead, zinc, iron and copper, besides minute traces of the precious metals; of the second class, the principal substances found are brick-clay, kaolin, cement-rock, limestone for burning into quick-lime, limestone for flux, glass sand, peat and building stone.

LEAD AND ZINC.

These metals are considered together because they are found occurring together in the same region and under exactly the same circumstances, being even obtained from the same openings. Lead has for many years been the most important metallic production of Wisconsin, and, together with zinc, whose ores have been utilized only since 1860, still holds this prominent position, although the production is not so great as formerly. Small quantities of lead and zinc ores have been found in the crystalline (Archæan) rocks of the northern part of the state and in the copperbearing rocks of the Lake Superior country, but there are no indications at present that these regions will ever produce in quantity. All of the lead and zinc obtained in Wisconsin comes then from that portion of the southwestern part of the state which lies west of Sugar river and south of the nearly east and west ridge that forms the southern side of the valley of the Wisconsin, from the head of Sugar river westward. This district is commonly known in Wisconsin as the "Lead Region," and forms the larger part of the "Lead Region of the Upper Mississippi," which includes also smaller portions of Iowa and Illinois.

What European first became acquainted with the deposits of lead in the upper portion of valley of the Mississippi is a matter of some doubt. Charlevoix (Histoire de la Nouvelle France, III, 397, 398.) attributes the discovery to Nicolas Perrot, about 1692; and states that in 1721 the deposits still bore Perrot's name. Perrot himself, however, in the only one of his writings. that remains, makes no mention of the matter. The itinerary of Le Sueur's voyage up the Mississippi, 1700-1701, given in La Harpe's History of Louisiana, which was written early in the 18th century, shows that the former found lead on the banks of the Mississippi, not far from

the present southern boundary of Wisconsin, August 25, 1700. Captain Johathan Carver, 1766, found lead in abundance at the Blue Mounds, and found the Indians in all the country around in possession of masses of galena, which they had obtained as "float mineral," and which they were incapable of putting to any use. There is no evidence of any one mining before Julien Dubuque, who, 1788 to 1809, mined in the vicinity of the flourishing city which now bears his name. After his death in 1809 nothing more was done until 1821, when the attention of American citizens was first drawn to the rich lead deposits of this region. By 1827, the mining had become quite general and has continued to the present time, the maximum production having been reached, however, between the years 1845 and 1847.

The following table, prepared by the late Moses Strong, shows the mineral production of southwestern Wisconsin for the years 1860 to 1873 in pounds:

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Until within the last decade the lead mines of the Mississippi valley, including now both the "Upper" and the "Lower" regions-the latter one of which lies wholly within the limits of the state of Missouri-have far eclipsed the rest of the United States in the production of lead, the district being in fact one of the most important of the lead districts in the world. Of late years, however, these mines are far surpassed in production by the "silver-lead" mines of Utah and other Rocky Mountain regions, which, though worked especially for their silver, produce incidentally a very large amount of lead. Nevertheless, the mines of the Mississippi valley will long continue to be a very important source of this metal. The lead ore of the Wisconsin lead region is of one kind only, the sulphide known as galena, or galenite. This ore, when free from mechanically mingled impurities, contains 86.6 per cent. of lead, the balance being sulphur. Small quantities of other lead ores are occasionally found in the uppermost portions of the deposits, having been produced by the oxidizing influence of the atmosphere. The chief one of these oxidation products is the earthy carbonate known as cerussite. Galena almost always contains some silver, commonly enough to pay for its extraction. The Wisconsin galenas, however, are unusually free from silver, of which they contain only the merest trace.

The zinc ores are of two kinds, the most abundant being the ferruginous sulphide, or the "black-jack" of the miners The pure sulphide, sphalerite, contains 67 per cent. of zinc, but the iron-bearing variety, known minerallogically as marmatite, generally contains 10 per cent. or more of iron. A ferruginous variety of the carbonate, smithsonite, also occurs in abundance, and is known to the miners as "dry-bone," the name being suggested by the peculiar structure of the

ore.

Both lead and zinc ores occur in limited deposits in a series of limestone beds belonging to the Lower Silurian series. The lead region is underlaid by a nearly horizontal series of strata, with an aggregate thickness of 2,000 feet, which lie upon an irregular surface of ancient crystalline rocks (gneiss, granite, etc.). The names and order of succession of the several strata are indicated in the following scheme, the last named being the lowest in the series:

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The first two of these layers, in the Wisconsin part of the lead region, are met with only in a few isolated peaks and ridges. The prevailing surface rock is the Galena limestone, through which, however, the numerous streams cut in deep and narrow valleys which not unfrequently are carved all the way into the Lower Magnesian.

The lead and zinc ores are entirely confined to the Galena, Blue and Buff limestones, an aggregate vertical thickness of some 350 to 375 feet. The upper and lower strata of the series are entirely barren. Zinc and lead ores are found in the same kind of deposits, and often together; by far the larger part of the zinc ores, however, come from the Blue and Buff limestones, and the lowest layers of the Galena, whilst the lead ores, though obtained throughout the whole thickness of the mining ground, are especially abundant in the middle and upper layers of the Galena beds.

The ore deposits are of two general kinds, which may be distinguished as vertical crevices and flat crevices, the former being much the most common. The simplest form of the vertical crevice is a narrow crack in the rock, having a width of a few inches, an extension laterally from a few yards to several hundred feet, and a vertical height of 20 to 40 feet, thinning out to nothing in all directions, and filled from side to side with highly crystalline, brilliant, large-surfaced galena, which has no accompanying metallic mineral, or gangue matter. Occasionally the vertical extension exceeds a hundred feet, and sometimes a number of these sheets are close together and can be mined as one. Much more commonly the vertical crevice shows irregular expansions, which are sometimes large caves, or openings in certain layers, the crevice between retaining its normal character, while in other cases the expansion affects the whole crevice, occasionally widening it throughout into one large opening. These openings are rarely entirely filled, and commonly contain a loose, disintegrated rock, in which the galena lies loose in large masses, though often adhering to the sides of the cavity in large stalactites, or in cubical crystals. The vertical crevices show a very distinct arrangement parallel with one another, there being two systems, which roughly trend east and west, and north and south. The east and west crevices are far the most abundant and most productive of ore. The vertical crevices are confined nearly altogether to the upper and middle portions of the Galena, and are not productive of zinc ores. They are evidently merely the parallel joint cracks which affect every great rock formation, filled by chemical action with the lead ore. The crevices with openings have evidently been enlarged by the solvent power of atmospheric water carrying carbonic acid, and from the way in which the ore occurs loose in the cavities, it is evident that this solving action has often been subsequent to the first deposition of lead ore in the crevice.

The "flat crevices," "flat sheets," and "flat openings," are analogous to the deposits just described, but have, as indicated by the names, a horizontal position, being characteristic of certain layers, which have evidently been more susceptible to chemical action than others, the dissolving waters having, moreover, been directed along them by less pervious layers above and below. The flat openings differ from the vertical crevices also, in having associated with the

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galena much of either the black-jack or dry-bone zinc ores, or both, the galena not unfrequently being entirely wanting. Cleavable calcite also accompanies the ores in these openings in large quantities, and the same is true of the sulphide of iron, which is the variety known as marcasite. These materials have sometimes a symmetrical arrangement on the bottom and top of the opening, the central portion being empty. The flat openings characterize the Blue and Buff and lower Galena beds, and from them nearly all the zinc ore is obtained.

It is not possible, in the limits of this short paper, even to mention the various mining districts. It may merely be said that the amount of galena raised from single crevices has often been several hundred thousand, or even over a million pounds, and that one of the principal mining districts is in the vicinity of Mineral Point, where there are two furnaces constantly engaged in smelting. Between the years 1862 and 1873, these two establishments have produced 23,903,260 pounds of metallic lead, or an average of 1,991,938 pounds, the maximum being, in 1869, 2,532,710 pounds, the minimum, in 1873, 1,518,888 pounds.

The zinc ores were formerly rejected as useless, and have only been utilized since 1860. An attempt to smelt them at Mineral Point was not successful, because the amount needed of fuel and clay, both of which have to come from a distance, exceeding even the amount of ore used, caused a very heavy expense for transportation. The ores are therefore now taken altogether to LaSalle, Illinois, where they meet the fuel and clay, and the industry at that place has become a flourishing one. The amount of zinc ore in the Wisconsin lead region is, beyond doubt, very great, and will be a source of wealth for a long time to come.

Since the ores of zinc and lead in this region are confined to such a small thickness of strata greatly eroded by the atmospheric waters, the entire thickness having frequently been removed, it becomes a matter of great importance to know how much of the mining ground remains at every point throughout the district. The very excellent topographico-geological maps of the region, made by Mr. Moses Strong, and since published by the State in the Report of the Geological Survey, make this knowledge accessible to all.

IRON.

Iron mining in Wisconsin is yet in its infancy, although some important deposits are producing a considerable quantity of ore. A number of blast furnaces have sprung up in the eastern part of the state, but these smelt Michigan ores almost entirely. Much remains yet to be done in the way of exploration, for the most promising iron fields are in the heavily timbered and unsettled regions of the north part of the state, and are as yet imperfectly known. It appears probable, however, that iron ores will, in the near future, be the most important mineral production of Wisconsin. The several ores will be noted in the order of their present im

portance.

RED HEMATITES.

The iron in these ores exists as an anhydrous sesquioxide, which is, however, in an earthy condition, and entirely without the brilliant metallic luster that characterizes the specular hematites. Pure hematite contains seventy per cent. of metallic iron, but the red hematites, as mined, are always so largely mingled with mechanical impurities that they rarely contain more than fifty per cent. The most important red hematite mined in Wisconsin is that known as the Clinton iron ore, the name coming from the formation in which the ore occurs. This formation is a member of the Upper Silurian series, and is named from a locality in Oneida county, New York, where it was first recognized. Associated with its rocks, which are limestones and shales, is constantly found a peculiar red hematite, which is so persistent in its characters, both physical and

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