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By George C. Bateman

I HAVE been introduced in the dual capacity of president of the Canadian Institute and Metals Controller for Canada. There are three particular points of similarity between these two positions. They are both temporary ; they both have to do with the mining industry ; and by a peculiar coincidence they both pay me exactly the same salary. It is difficult to appreciate the background of our present situation without knowing the really tremendous changes that have taken place since the last war. I sometimes think that even among ourselves we are likely to forget the extent to which our great mining industry has been expanded. In 1914 Canada's gold production amounted to only $16,000,000 and the suggestion was seriously ad¬vanced in Ottawa that the gold mines should be allowed to close down so that their men might be used in more important work. Today with a production at the rate of over $200,000,000 a year no one in Canada would venture such a suggestion because the output of our gold mines is the greatest single factor in producing dollar exchange, badly needed for the purchase of munitions and to maintain Canada's unbroken record of always meeting its obligations. Even with the severe restrictions now in effect against the importation of nonessentials, our imports for war purposes from the United States are resulting in the biggest adverse trade balance in our history. With us, gold mining ranks as an essential industry.

Jan 1, 1941

By AIME AIME

THE stage is set for the 1930 Annual Meeting. It will take place in the Engineering Societies Building. Feb. 17, 18, 19 and 20, and an unusual pro- gram of technical papers, symposia, lectures and addresses, interspersed with luncheons, dinners, excursions and worthwhile entertainment for the four days has been arranged. The curtain rises on Monday morning and the first act is by the entire company-registration. Then the meeting hits its stride, for there are ten technical sessions on Monday, and the range of subjects includes most of the Institute membership. The Committee on Coal and Coal Products, which is about to become the Coal Division, presents a symposium of a dozen or more papers on Coal Classification, concluding its afternoon session with several papers on general subjects. At its luncheon between sessions, C. E. Bockus, president of the National Coal Association, will be the honored guest. Papers of theoretical character will be discussed at the morning session of the Committee on Geophysical Prospecting; at its afternoon session there will be presented summaries of results obtained at various properties by methods described at previous meetings of this group and permanently recorded in "Geophysical Prospecting," published by the Institute early in 1929. Members of the Petroleum Division should not overlook the paper by Theodor Zuschlag, on this Committee's program. It is entitled, "Oil Structure Mapping by the Sundberg Method." Members of the Iron and Steel and Institute of Metals divisions will find it profitable to attend the session on Engineering Education on Monday afternoon. E. A. Holbrook has arranged a program of ten-minute talks on Metallurgical Education which are designed to get down to "brass tacks." and the practical man may, in discussion, contribute as well as learn. At 5 p. m. Thomas T. Read will lecture+ at Columbia University, on "Recent Progress in Economics of the Mineral Industries."

Jan 1, 1930

By R. W. Raymond

THE absence of a convenient glossary of terns connected with mining and metallurgy has long been felt by the general public. It is to meet this want, not to furnish a technical manual for experts, that the following glossary has been prepared. It originated in an attempt on my part to revise for publication the manuscript of a compilation prepared from the appendix of Yale's work on Mining Titles and one or two other sources, to serve as an appendix to a new work on mining law, about to be published by Mr. H. N. Copp, of Washington, D. C. This revision soon assumed, contrary to my original intention, the proportions of a reconstruction ; and with the consent of Mr. Copp, and for the purpose of receiving from my fellow-members valuable aid, I presented my still incomplete work as a paper at the Lake Superior meeting of the Institute, inviting from any quarter suggestions of new terms or better definitions to be incorporated in the glossary before its final publication. This invitation was so widely and generously responded to, that I cannot undertake to make in this place' individual acknowledgments to those members of the Institute, and professional colleagues outside of it, who hays favored me with ' assistance and advice. The labor bestowed upon this paper since its presentation, at the Lake Superior meeting has considerably exceeded that of its first preparation, as

Jan 1, 1881

By Larry A. Shiprnan

DEMANDS upon power plants by the war program in 1941 intensified problems of coal utilization. It was an outstanding year in that field. The domestic heating stove witnessed outstanding development; the research folks progressing so rapidly that the design of the "perfect" stove is just around the corner. Use of colored motion pictures in analyzing fuel-bed performances has reached a new high with the colored pictures taken at minute intervals and projected at sixteen frames a second as shown by the Koppers Coal Co. and the Anthracite Institute (on domestic stokers) and the Consolidated Edison Co. (industrial stokers). Continued efforts of this kind will be beneficial in analyzing further some of the "Code for Testing Coal" problems confronting Subcommittee No. 2 of the Joint A. I. M. E. - A. S. M. E. Committees.

Jan 1, 1942

By R. S. Busk, R. F. Marande

The magnesium-aluminum-zinc 'system contains most of the magnesium-base alloys used commercially, although in practice the ternary alloys are usually modified by the addition of a small amount of manganese. Table I contains the magnesium-base commercial sand-casting alloys most widely used throughout the world, together with their typical tensile properties. These alloys may be regarded as a single family of varying aluminum and zinc content, disregarding manganese. A concise means of presenting data for them is by means of iso-property lines plotted on triangular coordinate paper. Constitutional, casting, and mechanical properties are presented in this manner. The data are given with the obiect of providing reference material, and to aid in the choice of a commercial alloy to serve a particular purpose. Detailed, critical analysis of the commercial alloys has been covered in a previous paper.' All alloys reported were made in rj-lb. melts, superheated to r700°F. for 15 min., cooled to r400°F. and poured in sand molds. The test bars produced had a 1/2-in. reduced section and were about 6 in. long. Except for the data represented in Figs. I and 3 the alloys used were of commercial purity and contained 0.1 to 0.2 per cent Mn in addition to the aluminum and zinc. Constitutional Data Under the heading of Constitutional Data are included all known data on con-

Jan 1, 1946

By R. F. Marande, R. S. Busk

The magnesium-aluminum-zinc 'system contains most of the magnesium-base alloys used commercially, although in practice the ternary alloys are usually modified by the addition of a small amount of manganese. Table I contains the magnesium-base commercial sand-casting alloys most widely used throughout the world, together with their typical tensile properties. These alloys may be regarded as a single family of varying aluminum and zinc content, disregarding manganese. A concise means of presenting data for them is by means of iso-property lines plotted on triangular coordinate paper. Constitutional, casting, and mechanical properties are presented in this manner. The data are given with the obiect of providing reference material, and to aid in the choice of a commercial alloy to serve a particular purpose. Detailed, critical analysis of the commercial alloys has been covered in a previous paper.' All alloys reported were made in rj-lb. melts, superheated to r700°F. for 15 min., cooled to r400°F. and poured in sand molds. The test bars produced had a 1/2-in. reduced section and were about 6 in. long. Except for the data represented in Figs. I and 3 the alloys used were of commercial purity and contained 0.1 to 0.2 per cent Mn in addition to the aluminum and zinc. Constitutional Data Under the heading of Constitutional Data are included all known data on con-

Jan 1, 1946

By David P. Hale

The Cartersville barite district is near Cartersville, Ga., in the southeastern part of Bartow County, about 43 miles northeast of Atlanta. The area over which active mining is being done extends about six miles in a northeasterly direction and is about three miles wide. Barite production in Georgia began about 1907,' but the existence of the mineral was known much earlier. At present four companies are operating washing plants and three other plants are operating on leases from those companies. The chief impurities in the ores are silica and iron oxide. The silica is easily washed and jigged out and gives little trouble. Any gravity separation between the iron and the barite is generally poor, owing to the slight difference in specific gravity. Two operators have turned to magnetic separation as the solution to the problem and have made remarkable improvements in the finished product. By very close sizing prior to jigging, the separation between iron and barite has been greatly improved. In some localities manganese occasionally appears as an impurity, but is fairly easy to eliminate by gravity methods. A considerable percentage of iron and silica is eliminated by being broken free in crushing. Until methods for the recovery of fine ore were introduced a minimum of crushing was done, but modern methods allow more than formerly. The depression years brought about the need for increased recovery of ore handled on the part of the producers and a demand for a higher grade of product on the part of the buyers. Improvements in milling and mining practice have had a far greater effect, however, than merely the production of a better grade of ore with greater recovery. They have opened for mining large areas that a few years ago were considered noncommercial deposits because of their inaccessibility and their high iron content. It is no exaggeration to say that the new methods have more than doubled present known reserves of barite ore of economic value.

Jan 1, 1942

By David P. Hale

The Cartersville barite district is near Cartersville, Ga., in the southeastern part of Bartow County, about 43 miles northeast of Atlanta. The area over which active mining is being done extends about six miles in a northeasterly direction and is about three miles wide. Barite production in Georgia began about 1907,' but the existence of the mineral was known much earlier. At present four companies are operating washing plants and three other plants are operating on leases from those companies. The chief impurities in the ores are silica and iron oxide. The silica is easily washed and jigged out and gives little trouble. Any gravity separation between the iron and the barite is generally poor, owing to the slight difference in specific gravity. Two operators have turned to magnetic separation as the solution to the problem and have made remarkable improvements in the finished product. By very close sizing prior to jigging, the separation between iron and barite has been greatly improved. In some localities manganese occasionally appears as an impurity, but is fairly easy to eliminate by gravity methods. A considerable percentage of iron and silica is eliminated by being broken free in crushing. Until methods for the recovery of fine ore were introduced a minimum of crushing was done, but modern methods allow more than formerly. The depression years brought about the need for increased recovery of ore handled on the part of the producers and a demand for a higher grade of product on the part of the buyers. Improvements in milling and mining practice have had a far greater effect, however, than merely the production of a better grade of ore with greater recovery. They have opened for mining large areas that a few years ago were considered noncommercial deposits because of their inaccessibility and their high iron content. It is no exaggeration to say that the new methods have more than doubled present known reserves of barite ore of economic value.

Jan 1, 1942

By Richard J. Lund

Stock piling-and by that I mean well-organized stock piling on a substantial scale-is almost as old as the hills themselves. It was back in early Biblical times, as recounted in the Book of Genesis, that Joseph was charged by Pharaoh with the responsibility of stock piling food during the seven years of plenty to guard against the seven subsequent years of famine that were revealed by the Pharaoh's dream. And this same policy of storing up food or materials to provide for future anticipated emergencies can be traced repeatedly down through the ages. So our own efforts are anything but new. Our modern concept of stock piling-the purchase and storage of strategic materials to assure supplies needed in time of some future war- stems from our experience in World War I. In 1920, the War Department was charged by Congress with the responsibility of procuring all War Department supplies and mobilizing industry in the event of another war. During the two decades that followed there were many authoritative studies made of our deficient mineral problem, all of which pointed out the urgent necessity of stock piling certain strategic materials as a reserve against future war. One such study, made in 1925 through the combined efforts of the Mining and Metallurgical Society and the AIME, was done at the ex- press request of the War Department. Eight years later another more de-

Jan 1, 1949

By N. J. Grant, C. F. Flo, F. B. Cuff

An investigation of the Ti-Cr system has shown the presence of a complete series of solid solutions in the ß phase, with a minimum in the solid us near 50 pct Cr. An intermetallic compound, TiCr2, forms during cooling from the ß solid solution. There is a eutectoid reaction at the low chromium side of the system. IN view of the recognition of the potentialities of titanium and its alloys as important structural materials there has arisen a need for a systematic investigation of various titanium binary diagrams. Of these, the Ti-Cr system was of particular interest because of the improved properties imparted to titanium by small chromium additions. A literature survey disclosed a partial constitution diagram that had been suggested by Vogel and Wenderott,¹ This diagram, shown in Fig. 1, is the result of work done on the Fe-Cr-Ti ternary system. Alloys containing less than 43 pct Cr were not investigated. In addition to this, a study of alloys in the Ti-Cr system was reported by McPherson and Fontana.² Adenstedt3 furnished a number of dilato-meter curves obtained from specimens containing 5, 10, and 15 pct Cr. Very recently, McQuillan4 submitted a proposed diagram covering the complete range of compositions between titanium and chromium. This diagram was in general agreement with the one described here. Experimental Procedure Sponge titanium (99.7 pct) and electrolytic chromium (Bureau of Mines analysis: 99.03 pct Cr, 0.40 pct Fe, 0.53 pct O2) were used for the initial determination of the system. Subsequent refinement of points, particularly for the low chromium side of the diagram, was accomplished by using iodide titanium and high purity chromium (National Research Corp. analysis: 0.050 pct C, 0.045 pct O2). The Ti-Cr alloys were prepared by melting 25 g charges in an enclosed, water-cooled copper crucible using a movable tungsten electrode. The atmosphere was helium, prepurified by first passing it through a drying agent and then through sponge titanium heated to 850°C. Particular care was taken to avoid any large scale segregation resulting from insufficient mixing of the components. Each charge was melted and kept molten for approximately 1 min, allowed to cool, inverted, remelted, and kept molten for an additional minute. In order to ascertain the amount of impurity pickup (oxygen and nitrogen) during the melting procedure, three iodide titanium specimens were melted in sequence and then checked for increased hardness. The specimens in the as-cast condition showed a relatively large hardness increase over the hardness of the as-received iodide titanium. The scattering on these readings was large. However, after the specimens had been homogenized at 840 °C for 2 hr and slowly cooled, the measured increase in hardness over the as-received titanium was small with a corresponding decrease in scatter. The reason for this hardness change is that in heat treating these specimens below the transformation temperature (885°C) there was a conversion from the as-cast structure to the more nearly equilibrium structure of the annealed specimen. The alloys were analyzed for chromium content and although the actual percentage was invariably low the deviation from the nominal composition never exceeded 0.6 pct Cr.

Jan 1, 1953

By Henry F. Hebley

INTRODUCTION How often has the thoughtful observer pondered the apparent contradictions experienced in the weather? One can take records of two days, one in the winter and one in the summer. The "degree days" indicate that space heating and domestic load were present in one case and not in the other. The Business Index may be about the same, indicating that the industrial activity of the area and its concomitant use of fuel were about the same. Thus the volume of the products of combustion released to the atmosphere varied only as related to the space heating demand. Yet on one day in winter the atmosphere may be clear and bracing, while on a summer's day the air is thick and murky and the visibility sharply reduced. The situation may be reversed. What are some of the factors that contribute to the creation of these conditions? These few notes have been prepared to indicate some of the influences that are exerted on the problem. THE SOURCES OF ATMOSPHERIC POLLUTION The industrial area of Pittsburgh, Pa., has been a dominant center for the production of iron and steel for over one hundred years. In fact, with the growth of the numerous auxiliary processes Allegheny County which contains Pittsburgh is probably the most industrialized county in the world. In addition, the type of manufacture carried out in this area is predominant dependent on thermal energy (heat). That energy is supplied from coke and coal produced in the vicinity of Pittsburgh. Indicative of the stupendous quantities of fuel that are employed in this industrial area's economy, the following (Table No. taken from the U. S. Census (1940) may I of interest. An influence that has never been fully appreciated by many individuals is the fact that no matter what adventures the gases of combustion experience as they pass through the various processes, ulti¬mately the spent gases are discharged through chimneys to the atmosphere.

Jan 1, 1948

By H. D. Hoskold

This paper is presented in fulfillment of the promise made in my paper, " Remarks upon Surveying-Instruments,"" etc., and much of the material which would constitute an appropriate introductioil here is omitted, because it has been already published by the Institute, in connection with my own contributions- or those of Mr. Scott and others, in vols. xxviii. to xxxi. of the Transactions, and in the special Institute volume on Mine-Surveying Instruments. In these preceding publications will be found, for instance, descriptions of the writer's " miner's transit-theodolite" of 1863,† and his later " angleometer,"‡ both of which were steps of the progress in engineering instruments and methods which originated in the work of Bourns, before 1842, on the " BoxTunnel " of the Great Western railway in England, in which he had to make connections by direct telescopic sights down the shafts. About 1870 the writer devised a practical and much superior plan, and made detailed drawings for an instrument to meet all the conditions he had proposed prior to that year. The detailed plans were communicated to a celebrated optical firm in London; but, owing to their loss (in Paris or Germany, it is believed) and to other reasons, the matter was, for the time, allowed to lapse. Following upon Bourns's idea, my friend, the late Mr. Beansland, introduced, in 1856, a new system and a portable astronomical instrument.§ Such instruments, however, were neither common nor convenient, and did not come into general use among engineers.

Jan 1, 1902

By Dr. O’Neil Thomas J., Donald W. Gentry

"We should be concerned about the future be- cause we will have to spend the rest of our lives there. " -Charles Kettering INTRODUCTION Since the early 1970s, there has been no economic phenomenon that has been more widely discussed or experienced in the United States than inflation. Al- though its precise definition and measurement are elusive, inflation has had pro- found and extensive impacts on the manner in which nearly everyone lives. It is painfully obvious to consumers that inflation is characterized by a continuing up- ward spiral of prices. In a capital-intensive industry like mining, those increases can be positively breathtaking. An interesting example is shown in Table 1. Table I shows that on a unit basis, the equivalent 1980 capital cost of Cuajone was over six times the cost of the adjacent and quite similar Toquepala operation completed in 1959. Such sobering statistics weigh heavily on the minds of executives who are contemplating major investments in new mining facilities. In spite of its monumental presence, inflation has usually been either inadequately covered or totally ignored in textbooks on engineering economy. The reasons for this are not entirely clear, but a contributing factor is the inherent difficulty in accurately predicting inflation. However, under certain conditions, inflation may become the most important factor in a mining investment, and it can rarely be safely ignored in capital investment analyses. DEFINING AND MEASURING INFLATION Defining inflation and related terms is relatively easy. Its measurement, how- ever, is the source of almost endless debate in economic and political circles. How- ever, much of that debate is not relevant to the scope of this book, so that only those issues which impact directly on the capital investment decision are covered in this section. Inflation is the general decline in the value of money as measured by what it will buy. It is clear, then, that the rate of inflation varies with the particular currency under consideration as well as the type of goods and services being purchased. One would find, for example, that the general rate of inflation relative to German marks

Jan 1, 1984

By D. Hnrrington

THE Dust Symposium was attended by approximately 100 persons, nearly all of whom remained from the starting hour (2 p. m.) until the use of the auditorium was demanded for another meeting at 5:30 p. in. In calling the meeting to order, D. Harrington made a few remarks as to the importance of the health dust problem in mining as well as in general industry and expressed gratification that the subject is now out in the open and that mining people are desirous of ascertaining the facts. B. F. Tillson acted as chairman of the meeting. The milling executive who desires to know what to do to prevent his workers from being unduly exposed to the dust hazard can get much out of the paper by D. E. Cummings, who has been doing much work in mines trying to keep -the dust in the air within safe limits. His recommendations indicate that the main protection of the worker in mines is by adequate ventilation, supplemented by the extensive use of water in drilling, as well as in water curtaining to condition air both in regard to dust content and to temperatures. Blasting was shown to be one of the chief causes for dust and it was recommended that whenever feasible all blasting should be delayed to the end of the working shift.

Jan 1, 1935

By Carl F. Dietz, Dyke V. Keedy

The problem of drying ores is one that most mill-engvineers are sooner or later called upon to meet, and it may be timely to point out some of the difficulties resulting from such operations from purely a metallurgical and economic standpoint. We mean, in the following pages, to discuss primarily the effect of such operations on the ore. itself, without particular reference to the mechanical or cost features of the subject. That an appreciable tonnage of the ore fed to the usual form of drier, either rotary or stack, is lost, is fairly well appreciated, but we believe that only a few mill-managers know just what their drier-losses amouilt to, and we have found that in most cases they console themselves with the fact that the drier-smoke is not very much discolored, and it is generally believed that the draft is not sufficient to carry away more than a negligible percentage of the values.

Jan 1, 1913

By HARRY H. SMITH

IT IS my understanding that, speaking broadly, the function of the engineering profession is to find how to do the thing required better for less money. Mechanical engineers, mining engineers, and the various other kinds of engineers are engaged in discovering and effectuating new and improved methods .of producing better goods and services at less cost to industry. The savings and advantages, thus, accruing ace reflected from time' to time in increased productive powers of industry and lower costs to the public which consumes the goods and services.

Jan 1, 1931

By Stanley Kesler

The first of two initial 650-mw units of the Paradise Steam Station, located on the banks of the Green River in the south-central portion of the western Kentucky coal basin, is scheduled for operation in late fall of 1962. This plant will be the eighth large-capacity, modern station built by TVA in a series starting with Johnsonville, operated first in 1951. During the subsequent ten years, unit sizes have increased from a capability of 125 mw to 650 mw at Paradise. This new unit will take its place in a power system that serves an area of about 80,000 sq miles with a present installed capacity of over 12,000 mw. Upon completion of the Paradise units and other additional hydro and steam units presently under construction, the system capacity will have reached over 15,000 mw. Projected load estimates indicate that this system will provide a margin of slightly under 10% of dependable capacity above peak demand at that time. One Paradise 650-mw unit at that time will represent approximately 4yc of the total system installed capacity.

Jan 10, 1962

By C. E. Lawall

ONE of the most important developments in the coal industry during 1940 was the continued uptrend in the production of bituminous coal. Estimated production for the year is 450,000,000 tons, with an additional production of anthracite of 50,000,000 tons making a total of approximately 500,000,000 tons. This is an increase of 12.5 per cent over 1939. Despite an estimated decrease of about 3.5 per cent in anthracite production, all of the major coal-producing states had increases in production for 9140. The national defense program, with the consequent increase in industrial activity, undoubtedly had an important effect on the increased demand for coal.

Jan 1, 1941

By R. L. Stone

None of the currently used methods of testing bentonites as binders for strengthening iron ore pellets is entirely adequate by itself. Since more knowledge was needed about 1) which properties of bentonite most affect pellet strength, and 2) the precise mechanism by which strengthening is produced, attention was paid to possible new techniques for rating bentonites. With the structural nature of bentonites — in particular, the montmorillonite component — the possibility of rating bentonites on the basis of zeta potential was investigated. These bentonites were also rated by conventional tests and measurements, including colloid content, barrel yield, pH, chemical analysis and physical tests on green and dry pellets. A mechanism for pellet bonding based on electro-kinetic forces between the bentonite and the iron ore concentrate appears to be feasible. In pelletizing, from 6 to 18 lbs of bentonite is added per ton of concentrate to give strength to the green and dry pellets. In some operations even more bentonite than is required for strengthening purposes must be added for moisture adsorption to pennit balling of the concentrate. Since bentonite is thus a major item in pelletizing, more knowledge about the way in which bentonites act as binders and better ways of rating this ability would help in the difficult job of selecting the right bentonite for a given concentrate. The fact of the matter is that although several methods are in current use for testing bentonites, none of these methods are consistently foolproof. For example, a given bentonite may rate high by several standard tests yet turn out to be a poor binder, and of course the reverse also occurs. Actually, more knowledge is needed about 1) which properties of bentonite most affect pellet strength, and 2) the precise mechanism by which strengthening is produced. In this study attention is therefore paid to possible new techniques for rating bentonites. With the structural nature of bentonites as a starting point, we investigated the possibility of rating bentonites on the basis of the zeta potential, i.e., the electrokinetic ootential on the montmorillonite colloids — the main component of bentonite binders. The zeta potential technique was applied to a range of commercial bentonites from several areas in the U.S. and abroad. These bentonites were also rated by conventional tests and measurements, including:

Jan 1, 1968

By D. J. Blickwede

WHEN iron is dipped in molten zinc at temperatures in the range 840" to 930°F, the two metals react to form layers of Fe-Zn compounds which adhere to the iron. At the galvanizing tem- perature, the successive layers are:' y (Fe5Zn21), 61 (FeZn;), and 5 (FeZn13), in conformity with the Fe-Zn constitution diagram. There is no quantitative information in the literature on the rates of growth of the individual alloy layers over the temperature range 840° to 930°F. Rather all the past experiments have studied the loss in weight of iron as a function of galvanizing

Jan 1, 1954