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By H. B. Pulsifier

THE following report on the structure of copper is the result of work done in the laboratory of the Rome Wire Co. early in 1925. Previous work had indicated to the author that excellent results might be expected if a suitable technique in surfacing and etching could be developed. The resources of the Rome Wire Co. enabled this metal to be studied more intensively than previously, although none of the materials were investigated exhaustively. The material presented is hardly more than a preliminary summary of the most obvious character of the metal; a much longer research would have been necessary to solve many of the pressing problems connected with the casting and working of copper. The Rome Wire Co. has generously released the paper; to Dr. E. H. Darby, technical supervisor of the company, are due particular thanks for his appreciation of the importance of metallographic study of copper and for his effective support in the prosecution of the work and in making its publication possible.

Jan 1, 1926

By I. Ionel Gardescu

During the latter part of 1930 an agreement was reached among operators in Rumania to curtail the production of oil to about 100,000 bbl. per day. This agreement lasted only a few months and 1931 shows a new peak in production with an average yield of 136,900 bbl. per day as against an average of 116,600 bbl. per day for 1930. The total production for 1931 was 49,210,000 bbl.; an increase of 18.4 per cent over the previous year's production. It is interesting to compare the percentage production of the major companies to the potential production figures determined by the Government in September, 1930 (Table l), on the basis of which the proposed curtailment was to have been made. The three companies listed first in this table show an increase in average production for 1931 over their estimated potential production rating. This increase might be attributed at least in part to the recent development of the Boldesti field, which is controlled by these companies and of which the production at present is nearly 10 per cent of the total oil output for Rumania. Among the other fields, Moreni still holds first place with an output of 33.6 per cent, followed by Gura-Ocnitzei with 29.3 per cent. In both these fields the main source of oil is from the deeper Meotic sands. Other

Jan 1, 1932

By E. M. Norris

During the winter and spring of 1917, an unprecedented number of underground fires occurred in the Butte district. With one exception, these fires were caused by the failure of electrical equipment, and called attention to the increased fire hazard in underground mining operations occasioned by the extensive use of electricity. Five local conditions that contributed toward a heavy fire risk were: (1) The heavy continuous timbering necessary for mine supports; (2) the strong ventilating pressures in the shafts and main airways; (3) the subsidence and faulting movements in the country rock, which ruptured cables and displaced trolley and lighting wires; (4) the strongly acid mine waters, which quickly developed any weak points in the electrical insulation; (5) oxidation in old stopes containing large amounts of timber. In the summer of 1917, a comprehensive plan of fire prevention was begun by the Anaconda Copper Mining Co., which involved a thorough and intensive development of the preventive measures then in use. These were as follows: Fireproofing, remodeling and strengthening electrical insulations, extension of underground water system, control of ' ventilation, maintaining efficiency of fire-fighting crews, and reorganization of fire patrol. In considering the problems of fireproofing, it was immediately apparent that some method of applying a durable coat of fireproof material to the mine timbers was needed. The first experiments were made with a plaster composed of one part cement, one-half part fireclay, and three parts sand. This was applied by hand to a thickness of 1 in. (2.5 cm.) over a reenforcement of herringbone metal lath. It made a very satisfactory covering for fan stations, but was too soft and friable for traveling ways, where it was subject to abrasion. The cement gun was tried next with a three to one mixture of sand and cement. A 1/2-in. coating of gunite applied over poultry netting or metal-lath reenforcement proved

Jan 1, 1923

By E. M. Norris

During the winter and spring of 1917, an unprecedented number of underground fires occurred in the Butte district. With one exception, these fires were caused by the failure of electrical equipment, and called attention to the increased fire hazard in underground mining operations occasioned by the extensive use of electricity. Five local conditions that contributed toward a heavy fire risk were: (1) The heavy continuous timbering necessary for mine supports; (2) the strong ventilating pressures in the shafts and main airways; (3) the subsidence and faulting movements in the country rock, which ruptured cables and displaced trolley and lighting wires; (4) the strongly acid mine waters, which quickly developed any weak points in the electrical insulation; (5) oxidation in old stopes containing large amounts of timber. In the summer of 1917, a comprehensive plan of fire prevention was begun by the Anaconda Copper Mining Co., which involved a thorough and intensive development of the preventive measures then in use. These were as follows: Fireproofing, remodeling and strengthening electrical insulations, extension of underground water system, control of ' ventilation, maintaining efficiency of fire-fighting crews, and reorganization of fire patrol. In considering the problems of fireproofing, it was immediately apparent that some method of applying a durable coat of fireproof material to the mine timbers was needed. The first experiments were made with a plaster composed of one part cement, one-half part fireclay, and three parts sand. This was applied by hand to a thickness of 1 in. (2.5 cm.) over a reenforcement of herringbone metal lath. It made a very satisfactory covering for fan stations, but was too soft and friable for traveling ways, where it was subject to abrasion. The cement gun was tried next with a three to one mixture of sand and cement. A 1/2-in. coating of gunite applied over poultry netting or metal-lath reenforcement proved

Jan 1, 1923

By Peter A. Allen

INTRODUCTION Lac Minerals Ltd., a significant North American producer of gold and other metals for over three decades, recently completed the financing for its third discovery in an eight year period. From 1975 to 1982, three important gold deposits in Quebec and Ontario: namely Bousquet, Doyon and Hemlo, were located and tested by company geologists. When current development plans are complete, Lac will have injected $400 million into these deposits. A discussion of these projects and their financing reveals some extraordinary challenges faced by top mining management. Responses to these challenges developed by Lac management may interest executives planning to proceed with new North American gold or base metal mines. MINE DE BOUSQUET In 1976, we explored a property containing a large low grade surface gold deposit. The geologial setting was exciting and we tested recent rethinking about the volcanigenic genesis of gold and base metal occurrences. These ideas helped pus to persist in drilling a nearby conductor and 600,000 ton, 0.22 ounce/ton orebody was outlined. With gold at $Cdn.150 per ounce the feasibility was approved and work started February 1978. Availability of a company custom mill 35 miles away reduced our immediate capital needs to $8.5 million. First of all, understanding the geological significance of results at Bousquet was critical. Mine and surface exploration geologists at Lac are continually and closely working together to better understand the nature of gold deposits in the Shield. This management emphasis on both pure and mine geology meant that a much larger ore reserve could confidently be predicted. (A proposal to quickly develop and ship the ore to a nearby company mine was discarded.) Instead of designing just for the initial plan of 500 tons per day we therefore included headframe, shaft and hoisting capacity for 1,700 tons and provided a compartment for future shaft deepening. These prebuilt additions were welcomed within two years. The type of collaboration whereby surface and mine geologists make study and field projects of each other's problems sets the foundation for this predictive ability. At Lac, the traditional responsibility for and supervision of the mine geologist by the mine manager is modified by this collaboration. This adds interest and scope to the geologist's work and lets him think beyond production requirements. Besides such management considerations, dedicated, professional geologists with integrity and lots of practical experience are needed to plan successful developments like Bousquet. Second, projecting future bullion revenue was critical and our experience selling production for future delivery gave us a way to ensure that loan repayment at term would not be jeopardized by falling metal prices. Output from a single mine is often reduced or curtailed for numerous reasons, so "selling forward" is done best and with least risk by companies like Lac with more than one or two producing locations for that metal. At first, a forward marketing program was considered unwise, speculative and unorthodox by analysts and other producers. Declining markets in the early 1980s prolonged gold project capital recoveries however, and critics were better able to appreciate the usefulness of such a tool. The notion that gold miners shouldn't sell forward is rooted in the belief that long-run gold prices will rise as modern social theory implementation in democracies inevitably erodes currency values. Selling against this trend goes against this industry belief or "ethic" and is at odds with the company shareholder who expects the gold price to rise not fall. Nonetheless, an efficient tool is available to the gold producer (not to most other metal producers) to quickly disengage from adverse price trends or to lock in spot prices instantaneously for two years or more of profits. Gold had recently retreated from U.S.$200 to $104 and now had reversed to $150. Lac had been forced to close several of its producers during the late 1960s because central bank-controlled

Jan 1, 1985

By S. R. Seagle, R. Schuhmann, N. A. Parlee

Rates of CO evolution and CO absorption were measured for liquid-iron alloys containing from 0.15 to 4.4 pet C, using a modified Sieverts apparatus. The alloys were held in alumina crucibles, so that both crucible-metal and gas-metal reactions occurred simultaneously. The data are interpreted on the hypothesis that the C-O reaction rate is controlled by oxygen diffusion across the boundary layers at the gas-metal and crucible-metal surfaces. CARBON-monoxide evolution from liquid Fe-C-0 alloys is a key reaction in steelmaking processes, both in the steelmaking furnace and in the ingot mold. Also, this reaction probably is an essential step in the desulfurization of iron under blast-furnace conditions, for which carbon is the principal reducing agent or deoxidizer present in the iron. The thermodynamic properties of the solutions of C and 0 in Fe and the equilibria of these solutions with gaseous CO and CO, have been investigated in some detail and are reasonably well understood. However, while these equilibrium data have accumulated in the laboratory, other data have accumulated to show that equilibrium conditions are often not achieved under plant operating conditions. Thus, an understanding of the rate and mechanism of the carbon-oxygen reaction not only has theoretical interest, but ultimately may assume considerable practical importance. Reaction Mechanisms and Rate Equations The over-all reaction under consideration is C (in liquid Fe) + 0 (in liquid Fe) + CO (gas) [I] Although this appears to be a straightforward heterogeneous reaction, involving just two phases (liquid metal and gas), a wide variety of reaction mechanisms has been proposed. Different authors have expressed divergent views as to the nature of the rate-controlling steps. Accordingly, a brief discussion of the possible reaction steps will be given. 1) Homogeneous Reaction Within Liquid Iron— Feild' and Jette2 have applied chemical reaction-rate theory as if the C-0 reaction were a homogeneous, second-order reaction occurring within the liquid-metal phase. This mechanism necessarily produces CO "molecules" dissolved in liquid iron. In order to yield CO gas, the dissolved CO must nucleate CO gas bubbles, and the dissolved CO also must be transported to the bubble surface where it enters the gas phase. However, this mechanism is inconsistent with present concepts of the structure of liquid-metal solutions. 2) Reaction at Gas-Metal Interface—At the surface of contact between gas and metal, a second-order reaction between dissolved C and 0 may occur to produce a CO molecule which enters the gas phase. This reaction presumably involves an "activated complex" structure in the interface. Some such surface mechanism appears essential because the carbon and oxygen do not occur in the same species in the two phases and therefore must react in some way at the surface. At liquid-iron temperatures, calculations based on reaction-rate theory indicate that the surface reaction must proceed extremely rapidly and thus cannot be a rate-determining step in the C-O reaction under ordinary conditions.3 ccordingly when the over-all reaction is measurably slow, the surface reaction may be considered at equilibrium; that is Cc* Co* = m'Pco [2] in which Co* and Co* are the concentrations of carbon and oxygen (weight per unit volume of metal), respectively, in the liquid-metal phase at the interface, Poo* is partial pressure of CO in the gas phase at the surface (atmospheres), and m' is the mass-action constant for Reaction [I]. Since activities of C and 0 are not strictly proportional to concentrations, m' is not a true thermodynamic equilibrium constant but varies with carbon content.' 3) Mass Transport—If the reaction is to proceed at the gas-metal surface, as described above, dissolved carbon and oxygen in the liquid iron must come to the surface and gaseous carbon monoxide must move away from the surface. Details of the mass-transport mechanisms depend on the kind of system under consideration. For a stirred metal bath in contact with a CO gas phase, the transport of C and 0 to the surface can be described by 1 Do Mols CO evolved per sec = — 1/16— Do/do Agm (CO-Co*) = 1/12 Do/do Agm *(Co-Co*) [3] In this equation, Do and D, are the diffusion constants for oxygen and carbon in liquid iron, 6, and 6,. are the boundary-layer thicknesses, A,,,, is the

Jan 1, 1959

By Spencer S. Shannon

This chapter is concerned with the uses, geology, exploration, evaluation, preparation for markets, and future of 90thorium and 39yttrium, along with 14 rare-earth elements. The rare-earth metals or lanthanides were divided into three categories by Berzelius. The cerium subgroup is comprised of 57lanthanum, 58cerium, 59praseodymium, 60neodymium, and 62samarium. 61Promethium does not occur naturally. The terbium subgroup includes 63europium, 64gadolinium, and 65terbium. The remaining lanthanides are placed in the yttrium subgroup. Strictly speaking, yttrium is not a rare earth. Because the properties of yttrium resemble those of heavy rare earths, its name has been used as a designating adjective. The yttrium subgroup includes 66dysprosium, 67holmium, 68erbium, 69thulium, 70ytterbium, and 67lutetium. Rare-earth elements, especially those of the same subgroup, tend to occur together rather than in discrete minerals.

Jan 1, 1975

W. C. MATTESON (communication to the Secretary*).-The criticism and question raised by Arthur Knapp regarding the standardization of nomenclature is most important. Faulty rock classification-is generally the result of carelessness or ignorance on the part of the driller. Two remedies might be suggested. In a field where several large companies are operating on an extensive scale, a geologist from each concern might be assigned to superintend the gathering of well-log data and the classification of samples. The geologists from the several operating companies might then combine their data, which would doubtless give valuable information to all interested parties. At present, coordination is not a big factor, unfortunately, but the time will come when conservation will demand such systematic coordination on the part of competing companies. The second remedy lies in instructing and educating the driller to a thorough understanding of the importance of an accurate log and correct classification of the various formations. The writer does not agree with the statement that "90 per cent. of the logs as taken today are absolutely worthless to any one but the one who has taken the log." While mistakes in nomenclature often occur, the driller is generally able to classify the important water-, oil-, and gas-bearing formations with a fair degree of accuracy. Such information is often sufficient to permit accurate correlation and also constitutes valuable data for projection purposes. It must be borne in mind that to attempt to use well-log data in a strict scientific sense of accuracy is impracticable and impossible. A broad interpretation and a comprehensive knowledge of the practical limits of such' information are essential in applying it successfully. Even experienced geologists do not always agree on rock classification. The question as to what constitutes correct nomenclature should receive the earnest and immediate attention of geologists, operators, and producers. Although standard textbooks on geology give correct definitions and descriptions of the general rock species, such textbooks fail to develop the subject in sufficient detail for the work under consideration. A committee composed of appointed members from the American Institute of Mining Engineers, the Geological Society of America, and the

Jan 6, 1917

By H. R. Cooper

Beginning from the point of view that process control of ore flotation can be approached by on-line analysis of processing behavior, an equation was developed which has characteristics useful for a multi-variable feedback loop. The application of this equation to optimizing control with a data acquisition system will be discussed in Part 11. OBJECTIVE OF CONTROL The purpose of developing a feedback method for concentrator control is to provide a means for determining ore processing behavior in order that data describing the ore can be used to make appropriate changes in control conditions while the ore continues to flow through the flotation circuit. In absence of simple linear relationships between pairs of variables in the flotation process, attention is directed to the need for a generalized relationship which possibly would incorporate all pertinent variables. It would be possible to apply such an equation to the control of variables in a concentrator in real time according to operational requirements as ore gradually changes in quality and processing behavior. To meet this objective, it is necessary to define relationships describing flotation performance in terms of performance variables capable of being measured on-line, either with on-line instruments and analyzers or with manual methods lending themselves to quick determination of meaningful information. Relationships derived to meet this objective form a model for the flotation process. The evaluation of flotation parameters of the ore and the execution of control on the basis of the derived information while the ore is continuing through the process would constitute a feedback control system. Data for the following control and performance variables can be made available: 1) ore feed rate, 2) collector addition rate, 3) lime addition rate, 4) pulp density, 5) assay or multiple assays in feed, tails, or concentrate sufficient for material balancing, 6) particle size distribution in flotation feed, 7) froth height, and 8) frother addition rate. Other process variables, such as flotation air input and mechanical agitation intensity, are usually not considered as control variables and were not taken into account in this analysis. Other data, such as that describing the ore, would be useful for concentrator process control. However, information of this type (such as ore hardness, grain size of the mineral, chemical species of the mineral, and ore surface properties) being not presently measurable in the on-line sense, has the effect of causing disturbances in the system which can be detected only indirectly. The process control system being sought must recognize disturbances by their effect on measured performance followed by determining control changes to compensate for them in meeting the objectives of improved performance (perhaps higher throughput, maximum return, etc.). A suitable model for the process having capability of recognizing the effects of ore disturbances should provide the means for introducing proper compensation through control changes. This would be done by processing on-line data with the model to calculate coefficients reflecting ore characteristics. This procedure can only be applied in a typical flotation system when on-line data can be processed at faster rates than the usual rate at which the ore in flotation feed takes on significantly different characteristics. For example, material balance data can be accumulated in approximately 5-min intervals using on-line X-ray fluorescence analysis. The flotation system time constant might be 15 min including grinding. Ore changes having time constants longer than 1 hr could be accommodated using on-line feedback control by this procedure. FORM OF A FLOTATION MODEL A suitable form for mathematical expression of the flotation process is an equation involving rates, when each of the components entering into the separation can be treated independently by a rate equation. A first-order, kinetic rate equation can be written on

Jan 1, 1967

E. E. Olcott, New York City: Prof. Kemp's valuable description of the Lancaster Gap mine is in line with many other able contributions on the origin of mineral deposits that the Institute has lately brought forward. The splendid contribution that Prof.

Jan 1, 1895

By W. A. Van Voast, J. J. McDermott, R. B. Hedges

Many coal beds that will be mined in southeastern Montana are aquifers that provide essential local water supplies. Mine cuts along aquifer outcrops create almost imperceptible piezometric changes. Monitoring near such operations at Colstrip has detected almost no water-level declines in observation wells. Mine cuts between outcrops induce rapid storage depletion and associated piezometric depressions. One such cut near Decker induced 12.50 mj/day of flow from storage and created a piezometric depression of 3 m or more as far as 1500 m from the mine. No wells have yet become nonproductive but losses of some are inevitable as operations expand. Alternative supplies are available from aquifers stratigraphically below the disturbed materials. Effluents from active mines are chemically similar to other area waters because they are mixtures of ground waters entering the mine cuts. Occasional high concentrations of nitrate do occur, however, as residuals from explosives. Spoils generally consist of confined aquifers of wasted coal and coarse rubble at their bases, overlain by finer-grained sand,

Jan 1, 1980

By M. Gensamer

IN applied mechanics and in metallurgy the transition from elastic to inelastic action is a matter of considerable interest and importance. Often the first inelastic deformation is apparently quite homogeneous; that is, uniformly distributed throughout the specimen. Sometimes this deformation is heterogeneous; that is, localized; inelastic deformation proceeds to some definite amount in restricted regions before adjacent regions of the specimen are inelastically deformed. In such cases the deformation does not become homogeneous until the whole specimen has been deformed the amount corresponding to that for each localized deformation. If the test is stopped before uniform extension sets in, the heterogeneous character of the deformation is apparent on the surface of the specimen through characteristic markings, which have been called "Lüders"' lines, "Hartmann's" lines, the "Piobert effect," or simply "flow figures." These markings are the source of considerable trouble in fabricating operations, particularly in the deep drawing of steel sheet. In many cases where the transition is of this nature, the stress developed at the upper limit of the elastic range is greater than the stress during the period of heterogeneous deformation, giving rise to the familiar "drop of the beam" effect in testing. The amount of the yield-point elongation, as well as the value of the stress at the lower yield point (the value to which the stress drops when yielding begins), are functions of the temperature and the testing speed. Lower temperatures and faster rates of testing increase both the yield-point elongation and the yield-point stress. These matters have been ably discussed in a recent paper by Winlock and Leiter1 though, as brought out by the discussion of that paper, the phenomena are but little understood. The purpose of the present paper is to clarify the problem through the application of a simple principle, and to show that, through the application of this principle, a number of phenomena in the plastic deformation of metals become more readily understood. The principle is this: During homogeneous flow, the rate of work-hardening is greater than the rate of change of stress resulting from change

Jan 1, 1938

By J. C. Branner

DuriKg the past two or three years I have seen statements regarding the first discovery of fullers' earth in this country that seem to require correction or modification. One appears again in the Mineral Resources of the United States for 1909, part II., p. 738, where it is said that 'fullers' earth was firat discovered in the United States at Quincy, Fla., in 1893." In this connection the following bit of unpublished history concerning fullers' earth in the State of Arkansas is worthy of attention. In April, 1891, when I was State Geologist of Arkansas, a Swede named John Olsen, formerly a copper-miner in Michigan, but then living south of Little Rock, brought me a sample of what he thought mas fullers' earth. He reported that it was from near the town of Alexander, the locality being 1 S. 13 W., section 8, SW. quarter of the SE. quarter. My chemist, Dr. R. N. Brackett, analyzed the material, and reported: Per Cent. Silica,.....SiO2 .... 63.19 Alumina,.... A12O3 .... 18.76 Iron,.....Fe2O3 .... 7.05 Lime,.,...CaO .... 0.78 Magnesia,.... MgO .... 1.68 Potash,.... K2O ,... 0.21 Soda,.....Na2O .... 1.50 Loss on ignition,........7.57 100.74 Water at 110° to 115° C. = 7.84. Another sample from about the same locality, also brought by John Olsen, on analysis by Dr. Brackett gave :

Jan 1, 1913

By R. G. Hall

WHEN we want to interpret some problem which faces us at the present, if that problem be a social or political movement, we turn to the pages of history for 'information. If the problem be one of science or of industry we turn to the library of the subject and endeavor to translate the present from the experience of the past. I wonder if you would bear with me for a few minutes as I look back to the time when I was going through mining school and looking forward with hope, it is true and with confidence also, but still with some trepidation and an occasional qualm, to the month of June when the class of 1897 would be hunting jobs. Those were the years 1893 to 1897. Those years saw the Treasury of the United States so empty of gold that the President had to appeal to financiers to accept the country's promises to pay in return for $100,000,000 in gold. And the invectives that were hurled at both their heads for such a betrayal of the people sound strangely similar to those you read today being daily written and screamed at another President for taking us into the League of Nations or for not issuing bonds in huge amounts for unemployment relief, or for not adopting somebody else's particular specific for the relief of hard times.

Jan 1, 1931

By David Baker

IN a paper presented to the American Institute of Mining Engineers, September, 1904, entitled ? Improvements in the Mechanical Charging of the Modern Blast-Furnace,"' I showed the great fault of mechanical charging-devices to be that the materials charged by the dumping of the skip were separated, the coarse materials having high velocity, and the fine, low-thus giving paths of low resistance through the stock in the furnace, which resulted in unequal distribution of the furnace gases, unequal reduction, slips, scaffolds, irregular cutting of the. inwall, " off " iron, and increased fuel-consumption. I showed how this could be prevented by rotary distribution, through which the irregular distribution in one layer charged is compensated by charging the subsequent layers from successively varied positions of the charger, and becomes practically eliminated when the angle between two successive positions is a little more or less than an even fraction of a full circle. Of all the devices then on the market, the nearest approach to the ideal arrangement was found in the Brown distributor, a full description of which was given. The one defect pointed out, however, was the difficulty of maintaining so much mechanism on the top of a blast-furnace. Since the presentation of that paper, I have designed a very simple form of rotary distributor, which may be applied to any form of double-bell charger, retaining the perfect gas-seal, which is so admirably obtained by that construction. In seeking protection for this invention, I found no similar distributor on record in the patent offices of the various countries where application was made; but an application show-

Jul 1, 1906

By Wilbur E. Sanders

At some period during the operation of metalliferous and other commercially valuable mineral-deposits in connection with their underground mining, when the developments therein have become so extensive that their description is tedious and confusing, some scheme for naming or numbering the various workings and their parts is necessary for convenience of reference. A simple and symmetrical yet expansive system of classification must be devised, one that is capable of being extended to cover all possible exigencies and conditions of future operations within the property. Such a scheme, properly arranged, greatly simplifies communication between the various departments of the mining business, as, for instance, between the administrative and the operating departments of the concern, and is of the greatest assistance to the officers of the mine in enabling them to locate and describe particular points and parts of workings and specific kinds of work. Again, in the proper segregation and differentiation of mine-accounts, when they are carried out with that detail which will furnish ready information concerning the cost of a particular piece of work, or the various items and totals of expense connected with the development, operation and repair of each or all of the mine-workings, some such method of clesignatioi~ becomes a necessity. Moreover, such a plan is acl- mirably adapted to the needs of the mining engineer, who, in connection with his reports upon mining-properties, is sometimes required, in his descriptions of certain blocks of ore, to locate lists of assays of samples taken from many and various places, and to designate workings and parts of workings that are located in different parts of the mine, sometimes at points wide apart. To write out in full a sufficient description of any particular

Jan 1, 1907

By AIME AIME

INDUSTRIAL Pittsburgh, the center of the coal and iron and steel industry of the world, was host to the Coal Division at its Fall Meeting held there on Oct. 21 and 22 at the William Penn Hotel. The past year has witnessed remarkable progress in new methods of mining and burning of coal and many of the papers on the program discussed these developments. Nearly 100 had registered at the time of the first session on Wednesday morning and this number increased to 168 on Thursday. Owing to the large number of papers on the program, eighteen in all, it was necessary to hold group meetings on Thursday morning, with a capacity attendance at each meeting. . Chairman McAuliffe was on hand early Wednesday morning to open the meeting. George Otis Smith, representing President Lovejoy, came over from Cleveland where he attended the meetings of the Institute of Metals Division. Secretary Parsons arrived later from Cleveland and spent the whole morning with the executive committee of the Division. Doctor Smith, Secretary Parsons, and J. T. Breunich were the official representatives from Institute headquarters.

Jan 1, 1936

By Wilbur A. Nelson

In 1839, Gerard Troost,1 the first State Geologist of Tennessee, reported the occurrence of zinc ores in east Tennessee, in connection with the iron ores at Embreeville; in 1844,2 he refers to the zinc deposits of east Tennessee, especially the apparently rich deposits occurring in Jefferson and Claiborne Counties, while his ninth annual report 3 s a description of the zinc deposits of Jefferson County and a description of the most improved processes by which zinc is extracted from its ores. Yet, only during the last few years have these ores been successfully worked. As far as can be learned, prior to the systematic development of the Mascot district in 1911, no large-scale or successful operation of any of the zinc deposits was carried on. But in that year, after several companies had made considerable progress in developing the Mascot area and had proved a relatively extensive body of low-grade sulfide ore, the American Zinc Co. entered the field. It introduced modern methods of prospecting and mining and from the first was successful. Too great credit cannot be given this company for its pioneer work in a previously unimportant field. Throughout the history of its operations, the American Zinc Co. has confined its efforts to underground mining of the sulfide ore, sphalerite. This company has found that successful results in zinc mining in east Tennessee can be achieved only by expending large sums in prospecting and blocking out bodies of pay ore in sufficient magnitude for large-scale operations. At Mascot are located the mines of the American Zinc Co. of Tennessee, the mines being situated along the Southern Railway in the Ilolston River Valley, Knox County, about 13 miles northeast of Knox-ville. At first only open pits, which were worked for oxidized ores, were operated and the production was small. In 1900, the Roseberry Zinc Co. was organized and sank to a depth of 187 ft. what is now known as No. 3 shaft of the American Zinc Co. The upper 30 ft. was in residual clay,

Jan 1, 1925

By Basil B. Zavoico

CRUDE oil production in the United States during 1938 reached approximately 1,214,355,000 barrels, an average of 3,327,000 barrels per day, or 5 per cent below the 1937 record output of 1,279,160,000 barrels. The decreased production did not prevent the stocks of all products from increasing to a total of 575,954,000 barrels by Sept. 30, an increase of 10,957,000 above the total on Jan. 1, or an average daily storage increase in all products of 40,135 barrels. The increase in total stocks was made entirely in the refined products, stocks of crude oil during the first nine months of 1938 having actually declined 7,155,000 barrels to 299,671,000 barrels, or an average daily decline of 26,209 barrels. The 1937 reversal of the preceding five-year trend of discoveries totalling less than withdrawals was continued through 1938 with indicated reserve addition from both new discoveries and extensions considerably in excess of the

Jan 1, 1939

By AIME AIME

OUR own Institute of Metals and Iron and Steel divisions cooperated with the Iron and Steel Division of the American Society of Mechanical Engineers, the American Welding Society, and the American Society for Steel Treating in a busy week at Cleveland. The morning sessions were held at the Hotel Cleveland and the afternoon ones at the Auditorium, where the metallurgical exhibition under the auspices of the American Society for Steel Treating not only occupied the arena of the Auditorium but completely filled the huge adjacent Annex. In the intervals of sessions the members thronged the exhibits but in the evenings the local attendance was so great that if the crowds had been any larger it would have been difficult to see the exhibits. With so many firms, both producers of metals and of equipment accessory to their production and use, it would be impossible to mention them -all and unfair to single out a few, since no two individuals' judgment would coincide as to relative interest and importance. In any case an exhibit is a thing to be seen rather than described, and these were well worth seeing.

Jan 1, 1929