REPORT ON THE IRON MOUNTAIN SHEET BY ARTHUR WINSLOW, STATE GEOLOGIST. ERASMUS HAWORTH, ASSISTANT GEOLOGIST. INTRODUCTION. By Arthur Winslow. AREA AND LOCATION-RAILWAYS-TOWNS-INDUSTRIES. AREA AND LOCATION. The Iron Mountain sheet is named from the well-known Iron Mountain mine, situated in the northern portion of the area. It is a quadrilateral of 15' extent in latitude and longitude, and embraces an area of 236.44 square miles. It is included between the lines 37° 30' and 37° 45′ of north latitude and the lines 90° 30′ and 90° 45′ of longitude west of Greenwich. It covers portions of Iron, St. Francois and Madison counties. The location of the sheet with reference to county lines is shown in the following figure. It lies in the southeastern part of the State, being about 50 miles west of the Mississippi river, and less than 70 miles north of the Arkansas line. Fig. 1.-Outline map showing position of Iron Mountain sheet in Iron and adjacent counties. RAILWAYS. One railway traverses the sheet midway and lengthwise from the north to the south. This is the St. Louis, Iron Mountain and Southern railway, a division of the Missouri Pacific system. It is a single-track line, but heavily ironed and well ballasted. This is a line of heavy traffic between Texas and Arkansas and northern states, and large quantities of lumber, cattle, cotton and other farm products are shipped north. Two short switches or spurs have been extended from Iron Mountain and Middlebrook, connecting with the quarries at Graniteville. TOWNS. Three small towns and five small villages are situated within the sheet. These in the order of their population in 1890 as given by the eleventh census are as follows: 1. Iron Mountain (population 1101), on the Iron Mountain railway, is a mining town which has been maintained by the iron mines and dependent industries. The town was occupied almost exclusively by mine operatives. The number of these in past years was at times as much as 1000; this is now reduced to about 200, and hence the town is of much less importance. 2. Ironton (population 965), on the Iron Mountain railway, is the county seat of Iron county, and is a local trade center and point of distribution of commodities to the surrounding country. No special industry characterizes the place. It is provided with two flour mills. and one wagon factory. 3. Doe Run (population 956), is located in the extreme northwestern corner of the sheet, at the terminus of the Mississippi River and Bonne Terre railway. It is a small town, which originated about five years ago, with the inception of lead-mining at that point. It consists of residences of miners and mill men and a few stores. Pilot Knob (population 757), on the railway, about two miles northwest of Ironton, owes its existence chiefly to the iron mines and furnaces which were once actively operated here. It is essentially a town of residences. A few stores have been opened; but these are in part closed, with the abandonment of the mines. 5. Graniteville (population 721), about four miles southwest of Iron Mountain, has been built up by a large granite quarry industry which is maintained at that point. It consists chiefly of residences of quarrymen. It is connected by a spur with the main railway line, but the nearest depot is at Middlebrook, nearly three miles distant. 6. Arcadia (population 408) closely adjoins Ironton and is practically a part of it, though under separate control. It has no special industry nor is it a place of commercial activity. It is chiefly distinguished as a summer resort; several pleasant summer residences have been built and a large number of visitors from St. Louis are attracted here each year. It is pleasantly located in the valley of Stout's creek, surrounded by porphyry hills. It 7. Middlebrook, on the Iron Mountain railway, between Iron Mountain and Pilot Knob, is little more than a railway station. contains in addition, a few residences, stores and a beer depot. 8. Belleview, located about six miles west of Iron Mountain, away from the railway, is a small country village, containing two or three stores and a postoffice. INDUSTRIES. The industries of the Iron Mountain sheet consist principally of agriculture, mining and quarrying. The principal farm products are corn and hay; wheat and oats are raised to a more limited extent. Iron ore is mined and shipped in large quantities from Iron Mountain; the same was true of Pilot Knob a few years ago, but work there is, at present, practically abandoned. Quarrying is actively prosecuted at Graniteville, and many car loads of stone are shipped yearly from this point to St. Louis. The mineral products will be discussed more fully under the head of economic geology, and further description will, therefore, not be made here. In the southwestern corner of the sheet, the margin of the southwestern lumber region is included. One saw-mill is located near Hogan station, and shipments of lumber are made from there. As indicative of the extent and comparative importance of the various industries, the following figures of commodities marketed in Iron county during the year ending June 30, 1892, extracted from tables compiled by Hon. W. C. Hall as State Labor Commissioner, are introduced here: 1 The production of iron ore at Iron Mountain for the same period is given by the State Mine Inspector as 78,969 tons.. PHYSIOGRAPHY. By Arthur Winslow. TOPOGRAPHY-HYDROGRAPHY-SOILS-FORESTRY. TOPOGRAPHY. The topography of the Iron Mountain sheet, as illustrated in the frontispiece, is of a hilly or semi-mountainous type. It is made up of low peaks and knobs or larger masses, between which are comparatively narrow and broken valleys. Though only 50 miles west of the Mississippi river, where the altitude of that stream is about 300 ft. A. T., the lowest contour on the sheet is 700 ft. A. T., and the highest contour is 1700 ft. A. T. while the general level of the valleys is about 1000 ft. A. T. The distribution of the zones of altitude is well shown in the diagram opposite this page. From these conditions it follows that the declivity of the streams is great and their flow rapid; corrasion along these streams is consequently active and base-levelling cannot be considered to have begun. The country is in a youthful stage of topographic development. The influence of geology upon topography is here profound and everywhere discernible. The hills and mountains and the great mass of upland country, are mostly composed of Archean crystallines or of metamorphosed Algonkian rocks, while the surrounding and comparatively level valleys are composed of approximately horizontal Cambrian or Silurian strata. The Mountains and Hills.-The features of relief of this sheet are members of what we term the St. Francois' mountains. No great central mountain mass is to be recognized here, however, of which the spurs and flanking ridges constitute the minor elevations. Neither have we a series of massive ridges or ranges as in the Appalachians 1The porphyry and granite mountains of southeastern Missouri have, up to the present time, been without a distinctive name. They have frequently been included under the term Ozark mountains. The Ozark mountains, as we define thein, constitute the great platean of Cambrian or Silurian rocks lying west of our area. It is a platean in which the streams have cut deep, long and narrow valleys, separated by broad flat-topped divides or by long, narrow hog-back-like ridges. It is of post-Silurian age. The St. Francois mountains, on the contrary, are composed almost entirely of massive Archean rocks; they consist of many separate individuals, of varying size and shape, but approaching the dome or conical form as a rule; they are of pre-Silurian age. They differ thus, in material, structure and age from the Ozarks, and hence deserve a separate name. St. Francois (pronounced St. Fran-cis) is here applied as a name long associated with this region. It is the name of the county in which a large portion of these mountains occur, and is the name of the principal river traversing this region. |