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FOREWORD A SERIES of papers on strategic and otherwise important mineral products was prepared some ten years ago under the joint auspices of the Committee on Foreign and Domestic Mining Policy of the Mining and Metallurgical Society of America and the Committee on Industrial Preparedness of the American Institute of Mining and Metallurgical Engineers. These papers were later published in a joint volume entitled International Control of Minerals (1925). Amongst them was one on manganese. The Subcommittee on Manganese prepared its paper in two forms. One was intended for inclusion with the series above referred to and approached its subject more particularly as an international problem. The other dealt more definitely with manganese as an element in the problem of national defense. This last was first written under date of January 24, 1924 as a confidential report, for and at the request of the War Department. It was later released and published, in slightly modified form, as a separate pamphlet by the Industrial Preparedness Committee of the American Institute of Mining and Metallurgical Engineers. After the lapse of eight years, in view of the vital position of manga-nese in the problem of industrial preparedness against a war emergency, the War Department made a request to have the conclusions of 1924 reviewed and brought up to date. To comply with this request the manganese subcommittee was reconvened (with a somewhat changed personnel) and exhaustive studies were once more made of the entire subject of manganese. A new report, with specific recommendations, was submitted to the War Department in February, 1932. This second report is now herewith released for publication. Certain specific conclusions and recommendations as expressed to the War Department are omitted. Otherwise the report stands as prepared and submitted by the manganese subcommittee of 1931. The members of this committee were: C. Minot Weld, Chairman, R. C. Allen, Arthur S. Dwight, J. W. Furness, D. F. Hewett, Reno H. Sales, Theodore Swann and Scott Turner. ARTHUR S. DWIGHT, Chairman, Committee on Industrial Preparedness.

Jan 1, 1933

By A. A. Steel

DUring the summer of 1905 I was employed by the U. S. Geological Survey to investigate the geology, mining, and preparation of barite in most of the fields of the United States. The Eastern districts have been more or less completely described; the Virginia field in detail by Thomas L. Watson, in his paper, Geology of the Virginia Barite-Deposits,' and other fields in abstract, including statistics of production and references to current literature, by various authors.2 There have also been published a few details of the occurrence of barite in the lead-mines of Washington county, Mo.³ The other accounts of this district are erroneous and meager, and since this field is the most important one in the United States at the present time, a detailed description of the local geology seems doubly desirable. Barite-deposits are scattered over nearly the whole of Washington and adjoining counties, but the product is all mined from the areas indicated upon the sketch-map, Fig. 1, and is shipped from the stations of the St. Louis, Iron Mountain & Southern railway, between Blackwell and Potosi, from 45 to 60 miles SW. of St. Louis. The topography is for the most part gently rolling, with slightly graded streams, usually less than 200 ft. below the higher hill-tops. Along Mineral fork and Indian creek are some steep bluffs and cliffs, affording good exposures of the

Jan 1, 1910

By D. W. Fuerstenau

Recently R. J. Charles1 showed that comminution of brittle or semi-brittle materials in batch operations is described more appropriately by a variable energy relationship than by the specific relation- ships proposed by Rittinger,2 Kick,3 and Bond.4 That is, the value of n in the empirical differential operation which applies to crushing and grinding (Eq. 1) is variable. Independently, Holmes6 developed an identical generalized equaton for size reduction. The experimental data of Charles and Holmes show that the value of n is determined by the material and the comminuting machine and is constant for a given combination of these two conditions. The general objective of the present article is to extend the Charles-Holmes concepts to continuous ball milling. The specific objective is to analyze the operation of a vibratory ball mill dry-grinding chromite in a continuous open circuit and to develop an equation for the comminution of chromite in this mill.

Jan 12, 1959

By E. A. Gulbransen, J. W. Hickman

IN a previous paper1 the authors have investigated the structure of the oxide films formed on most of the metals that make up the alloys of this study. The metals were studied in order to provide basic information on the structures, both physical and chemical, of the oxide films and to determine how these structures are effected by the temperature, time of oxidation, and surface preparation. It was felt that an understanding of the physical and chemical structure as well as the stability of the oxide film might furnish clues as to the nature of the reaction process and the protective quality of the film. The oxidation of the metals was studied over the temperature range 300° to 700°C. except for copper, where the range selected was 100° to 500°C. The results of these studies were presented in graphical form as existence diagram, of the oxides on a time-temperature scale. For some of the metals the existence diagrams were simple and showed few chemical transitions, but there were numerous cases where the physical state of the oxide surface was a function of time and temperature. In general the physical state of the oxide surface changed with increasing temperature so as to increase the sharpness of the diffraction patterns and to cause orientation effects to be more pronounced. Deviations in lattice parameters from X-ray values were noted. In general these deviations were of positive nature and may be due to solid solution of the metal in the oxide lattice. This effect might be expected in thin oxide films. In a study of the oxidation of alloys containing two or more metals, there may arise the complicating factor of identification of the oxides formed. A thorough understanding of the oxides formed on the pure metals, therefore, was, essential before investigation of the oxidation of alloys. In this paper it is our purpose to present a study of the following problems: I The existence diagrams of various alloys. [2.] The effect of the structure of the [ying] metal on the existence diagram of Iron. 3. The effect of the percentage of chromium on the oxides formed on Fe-Cr alloys. 4. The relationships, if any, between the oxides formed and the protective quality of the oxides. The following alloys are included in this study: alloys of iron with body- centered cubic, face-centered cubic and other metals, 13 Cr-Fe, 18-8 stainless steel, K42B1 Nichrome V, Hipernik, Inconel, Stellite " 21," Refractaloy, Kovar, mild steel, a series of Cr-Fe alloys and a series of Co-Fe alloys. Since many of the commercial alloys in this list contain more than two metals, various complicating factors in the identification of the oxides formed may arise.

Jan 1, 1946

By Lewis Reeve

As. part of a program of investigation of the properties of electric arc welds carried out in the laboratories of the A. 0. Smith Corporation, considerable work has been done on the determination of the oxygen, nitrogen and hydrogen content of different types of weld metal, employing for this purpose the so-called "vacuum fusion method." It is the purpose of this paper to describe certain improvements that have been introduced in this method of determining the gas content of metals, with particular references to the steel specimens examined in this investigation. The method and apparatus used at the beginning of the investigation were essentially those of the Bureau of Standards as described by Vacher and Jordan.1 Later a number of changes were introduced which resulted in. more rapid evacuation of the graphite crucibles employed and which enabled larger volumes of gas to be dealt with than could be handled conveniently in the Bureau of Standards equipment. In addition, the analyzing of the gases evolved from a melt in the same apparatus as collected was abandoned in favor of analysis outside the equipment using standard methods of gas analysis. The time required for gas analysis in the apparatus itself, as described by the Bureau of Standards, was found to be considerable, and during this time the rest of the equip-ment was tied up, preventing its use for the analysis of further steel sam-ples. As a result of the modifications introduced, the time required for the analysis of a steel sample for gas content was reduced from about 8 hours to less than 3 hours. Subsequently, the whole procedure of melting the sample and collect-ing the gases evolved was modified so as to enable a distinction to be drawn between the easily reducible oxides such as iron oxide and the more stable oxides such as silica and alumina. At the same time evidence was obtained indicating the probable existence in the steels of other nitrides than those of iron alone and making possible their quantitative determination.

Jan 1, 1933

By J. M. Lommel

DURING an investigation into the effect of heat-treatment on the creep properties of the magnesium alloy ZW1, (1 pct Zn, 0.6 pct Zr), the previously published methods of final polishing were found to be unsatisfactory. A new diamond-polishing technique has been developed to facilitate the study of fine precipitates in this and other magnesium alloys, and is described in this note. The sectioning and coarse grinding techniques are those of Fox and Hall,' and Hess and Cieorge.' Pre- liminary mechanical polishing is done with 6-µ, and 1-µ( grades of diamond compound on 'Microcloth' using a lubricant of 'Hyprez' oil. When the conventional technique is used with a 1/4- µ diamond wheel for the final polishing of magnesium alloys, scratching is likely to result from the abrasive action of the 'Microcloth' nap on the soft metal surface. This problem has been overcome by the use of a cream on the wheel in order to separate the specimen surface from the polishing cloth. To prepare this cream, a solution of 6-ml tri-ethanolamine in 75-ml water is stirred into 12.5 g stearic acid at a constant temperature of 80o to 90°C. The cream is allowed to cool, and is then 'whipped' to a smooth consistency with 100-ml 'Hyprez' oil. Before polishing, the diamond loaded 'Microcloth' is moistened with a few drops of 'Hyprez' oil, then a small amount of cream is worked into the nap. For the best results a wheel speed of 500 rpm should be used for polishing, and the specimen should be held by hand with a light pressure while being rotated in the opposite direction to the wheel. After polishing it is necessary to swab the specimen thoroughly in methylated spirits to remove residual cream and oil from the surface in order to avoid uneven etching and drying stains. Fig. 1 shows the surface finish obtained on a specimen by polishing on a 1/4- µ diamond wheel using the cream, and Figs. 2 and 3 the precipitate observed in ZW1 after polishing, and etching for two seconds in nitric acid 15 pct in ethylene glycol. This new diamond-polishing technique has made a valuable contribution to the programme of metal-lographic research on ZW1 and has become a routine laboratory practice for other low alloy content magnesium alloys.

Jan 1, 1961

By G. St. J. Perrott

During the past year, the Bureau of Mines has carried on an investigation of liquid-oxygen explosives (L.O.X.) to supplement the work described in previous publications.' The present paper gives results of the first part of this work, which was a laboratory investigation of the properties of typical combustibles used in L.O.X., and the relation of these properties to the absorption and retention of oxygen by the explosives and their explosive characteristics. No attempt will be made to describe the development of liquid-oxygen explosives, because this phase of the subject has been well covered.2 The L.O.X. cartridge consists of a paper wrapper filled with an absorbent combustible material that is saturated with liquid oxygen by soaking it therein. After saturation, the cartridge is removed from the liquid and fired with fuse and cap, or electric detonator, in a manner similar to other explosives. Certain types of cartridge may be detonated with fuse alone, requiring no cap to initiate the detonation. ' By suitable variation of the nature and density of the combustible, cartridges having a wide variety of explosive characteristics may be made.

Jan 1, 1925

By Charles S. Barrett, Robert F. Mehl, Shueling Woo

WHEN one solid phase is generated from another, fixed and rational orientation relationships are observed to subsist between the parent and the new crystal. The principle has been proposed' that the relationships obtaining between the same two phases are identical whatever the type of phase change involved, or whichever of the phases may act as parent. Many types of phase changes have been studied: allotropic transformations in pure metals, precipitation from solid solutions, eutectoid decompositions, peritectic reactions, the formation of oxide layers, and others.2 Phase layers generated by diffusion of one metal into another constitute an additional type of reaction. This report provides new data on the orientation relationships occurring between , phase layers formed by diffusion, in the Cu-Zn system, § and furnishes further evidence in support of the principle. MATERIALS AND METHODS The Cu-Zn system is especially suitable for these studies since the high vapor pressure of Zn provides an opportunity readily to create one phase poorer in Zn upon a parent phase richer in Zn by removing Zn by vaporization, or to reverse this process by adding Zn from Zn vapor; e.g., the beta phase can be found as a layer upon gamma by dezincing, or gamma can be found on beta by addition of Zn from Zn vapor. Since orientation relationships are to be sought, requiring crystals large enough for orientation determinations, it is convenient to prepare single crystals or large grains of the parent phase. The samples were prepared from oxygen-free high-conductivity copper and Horse Head zinc by melting under a borax flux in a graphite crucible. Large crystals of beta brass were grown by the strain-anneal method, in plates sectioned from the cast ingots, by the following procedure. Rockwell-hardness indents were made at I cm. intervals-and with various loads, then the plates were annealed for .4 days at 700°C. in Nichrome boxes packed with beta-brass chips and graphite. Surface layers were removed by grinding and etching to a depth of about 1.0 mm., and individual grains were cut out. Crystals of alpha and gamma brass were prepared by freezing, by lowering a graphite crucible at speeds less than one inch per hour through a furnace held at a constant temperature above the melting point. Single crystals were cut out with a jeweler's saw, ground, polished and etched. Care was taken to remove cold worked layers from the finished crystals

Jan 1, 1944

By Lawrence B. Wright, Lester G. Morrell

ON the steep slopes of the Kootenays, 15 to 20 miles south of Nelson, B. C., are a number of ore occurrences (Fig. 1). One that has many features of mining and geological interest is the Ymir Yankee Girl Gold Mines Limited. Discovery of this property was made in 1899 at an outcrop on the hillside, some 2500 ft. above the village of Ymir. This proved to be a branch vein 20 ft. long leading to two main veins, the Yankee Girl and the Spur (Fig. 5). The ore pattern as now delimited shows a remarkable increase in ore area with depth below the outcrop. This recent development is of interest particularly in view of the fact that the property was nearly condemned, professionally. Another interesting feature, which has a bearing upon its history, is the persistent excess of tonnage produced from period to period over visible reserves. This is not ascribed to lagging mine development, but to detailed vein characteristics, which we will endeavor to make clear by giving a description of the veins and their surroundings. HISTORY AND PRODUCTION Little interest was evidenced in this district until the building of the railway in 1893 provided easy access and the discovery of the Ymir mine [t] in 1896 attracted attention. As a result, the Ymir Yankee Girl group of claims was staked in October 1899. In 1907, an American syndicate took over the property and subsequently extended the 50-ft. drift and opened the present 400 and 540-ft. levels. In 1908, the Syndicate, without recording any shipments in the meantime, dropped its lease, which was taken up by H. L. Rogers, who bonded the Yankee Girl group. Rogers shipped 2622 tons of ore, mainly from the uppermost stope in the mine, which is reported to have yielded

Jan 1, 1938

By Paul Gordon

The distribution coefficient, k, of interest in zone refining is generally defined as the ratio of the solid to the liquid solubilities of one element in another at the normal melting point of the solvent. In practice, distribution coefficients are frequently calculated from solubilities at temperatures well below the melting point of the solvent, e.g., at a eutectic temperature. This is done because of the general lack of accurate data on the liquidus and solidus curves in most phase diagrams. The practice is equivalent to assuming that the liquidus and solidus curves are straight lines in the temperature range between the melting point of the solvent and the temperature at which data for the solubilities are known. It is recognized that the k values so derived may be in serious error; we have found evidence in recent zone-refining operations that a case in point is silicon in aluminum. The phase diagram found in the literature for silicon in aluminum indicates a eutectic on the aluminum-rich side at 12.5 at. pct Si and at 577°C,1 and a solid solubility of silicon in aluminum at this temperature of 1.59 pct.2 It also shows the liquidus and solidus as nearly straight lines from 577°C to the melting point of aluminum (660°C)1,2 The k value obtained from this data is 0.13. This is almost exactly the same as the k value (about 0.14)' obtained in a similar way for copper in aluminum. Yet we have found by mass-spectrograph analyses* of three bars of zone-refined aluminum that copper is efficiently removed from aluminum by zone refining but silicon is not. Two of the three bars of aluminum were zone-refined in our laboratories, the other in the laboratories of AIAG Metals, Inc. The former two bars, designated bars PG2 and PG3, were 30 in. long by 1 in. in diameter during refining; each was processed in a high-purity graphite boat* and kept under refining stage of the process consisted of thirty unidirectional zone traverses at rates of about 1 to 2 in. per hr, with a zone length of 1 to 2 in. At approximately the middle of the refining period a 6-in. piece of the impurity-laden finishing end of the bar* was cut off and replaced with new start- ing material. Following refining, the purest 20-in. section of the bar (obtained by discarding approximately 2 in. of the starting end and 8 in. of the finishing end of the bar) was leveled and then analyzed. The AIAG bar was 16 in. long and about 1.2 in. in diameter; it was purified by eight passes of a 2-in. zone at a rate of 1.6 in. per hr, the bar being contained in a sintered alumina boat lined with loose alumina powder of the highest purity. Data for the silicon and copper contents of the three refined bars are given in Table I. Derived data for the efficiencies of the zone-refining operations are listed in Table 11. It is clear from these two tables that the copper is removed much more efficiently—by a factor of 10 to 50 times—from aluminum during zone refining than is silicon. For example, in bar PG3 the thirty zone passes reduced the copper content from 10 to 0.02 ppm, i.e., by 500 times, whereas the same treatment lowered the silicon content by only a factor of about 16. It seem virtually certain, therefore, that the distribution co efficient, k, for silicon in aluminum is well above that for copper and is very likely not much below unity. This also implies that the solidus line on the aluminum-rich side of the A1-Si phase diagram is very probably appreciably curved near the aluminum melting point since the phase-diagram data indicate such curvature is unlikely in the liquidus.

Jan 1, 1965

By R. W. Fenn, H. A. Lepper, W. R. Hibbard

THIS paper reports the results of static tension and torsion tests made on single crystals of alpha brass for the purpose of determining its elastic coefficients. 70-30 alpha brass was chosen because it has been used extensively in the study of the plastic deformation and because it has the following desirable characteristics: (1) face-centered cubic structure, (2) marked elastic anistropy, (3) low elastic modulus. In 1928 Masima and Sachs' using static methods reported the following values for the elastic coefficients of 72-28 pct alpha brass: S11 = 19.4 X 10-13' cm2 per dyne S12 = —8.35 X 10"' cm2 per dyne S44 = 13.9 X 10-13= cm2 per dyne These values were obtained from the measurements shown in fig. 1. The experimental points for both tension and torsion lie consistently below the lines drawn to represent them. Fig. 2 shows the stress-strain curves for their specimens. Only a few points in the elastic range of these curves were available to obtain their values for Young's modulus. Therefore, it was considered that a re-evaluation of these data was desirable. In addition a variation of from 1.13 to 1.485 kg per mm2 was found in the values of the critical resolved shear stress for 70-30 alpha brass reported by Burghoff,² Treuting and Brick: Martin,4 Maddin, Mathewson and Hibbard5,6 and von Goler and Sachs.' Therefore, it was desired to evaluate the conclusion of Boas and Schmid8 that a constant resolved shear stress and not a constant elastic shear initiates plastic deformation. Theoretical Considerations*: The elastic deformation of cubic crystals may be defined by three elastic coefficients (S11, S12, S44,) or three elastic parameters (C,,, C,, C,,). These coefficients or parameters are sufficient to define the stress and strain relations for cubic crystals in the generalized form of Hooke's law referred to Cartesian coordinates. Elastic parameters and coefficients in the cubic system are related by the expressions: C11 —S11+S12/(S11-S12)(S11+2 S12) C12=-S12/(S11-S12)(S11+ 2 S12) (S11 — S12) (S11 + 2 S12) [2] C44 =1/S44 PI It is possible to determine all the elastic coefficients for a cubic metal by measuring two of the three elastic constants: Young's modulus (E), torsion modulus (G), or compressibility (S). The following relations exist between crystallographic orientation and E, G and S for cylindrical crystals of the cubic system: 1/E = S11 — 2 [(S11 - S12) — Su] (?1² ?2² + ?2²?83 + ?3² ?1²) [4]

Jan 1, 1951

By Oliver C. Ralston

A definite field of usefulness has developed for the brine-leaching processes of removing lead from ores and other products, so this paper reviews the developments, both in practice and in research, that have taken place since the publication of two earlier papers on this subject.' Several commercial plants are now in operation and a number of semi-commercial test plants have been operated in an effort to determine the limitations of brine leaching and to compare the results with other forms of treatment. Briefly, the brine leaching of lead depends on the fact that lead chloride and lead sulfate are soluble in saturated sodium-chloride solutions. In dilute brines, the solubility of the lead salt is less than in pure water; but in the strong brines, the solubility is greater than in pure water due, supposedly, to the formation of a double sodium-lead chloride. This is seen in Fig. 1, which shows the results of M. Demassieux2 on the solubility of lead chloride in sodium-chloride solutions of different concentrations and at three temperatures. The curves are not those given by Demassieux but are calculated from his results in order to convert them to units common in metallurgical work. The right-hand branch of each curve shows that if the solution is kept in contact with solid sodium chloride the lead chloride can be almost entirely displaced from solution, but that brines which are saturated with sodium chloride, but are not in contact with the solid salt, have a very high solubility for lead chloride. The diagram gives the analysis of the solution in grams of lead per liter, although the substance actually in solution is lead chloride. At 100" C. as much as 100 gm. of lead per liter can be obtained; but at lower tem-

Jan 1, 1924

By David R. Maneval, W. E. Foreman, J. Richard Lucas

INTRODUCTION The objective of this chapter is to inform the industry, as well as the public, of the challenges in dealing with problems associated with air and water contamination by coal preparation plants. The need for an informed industry is most important. It is hoped that some contribution may be given to a more efficient and economical approach to the problems of plant waste contaminants at individual plants. The problem has many facets, and consideration should be given to specific areas before any significant problems develop at a given plant. It is then possible to have a reasoned approach before the pressures of an emergency environment force hasty and incomplete solutions. It will be necessary to anticipate these problems in the design of new preparation plants, and advance consideration should be given to all problems concerned with contaminants.

Jan 1, 1979

By J. D. Hanawalt, W. H. Gross

Magnesium has long been known as the lightest of our engineering metals. This metal, silvery white in color, has a specific gravity of only 1.74. Aluminum, the next lightest structural metal, is 1 ½ times heavier; zinc is 4 times heavier; iron and steel are 4 ½ times heavier; and copper and nickel are 5 times heavier. Magnesium does not occur in the free state but is very abundant in nature, constituting 2.5 pct of the earth's crust in the form of various ores. It is the third most abundant structural metal, being exceeded only by iron and aluminum. Magnesium is unique, however, in that in the form of magnesium chloride it also exists in the oceans. Sea water is the source most widely used for production in the United States but magnesium is also commercially produced from magnesite, dolomite, and other ores as well as from certain inland brines. The vast quantity of magnesium existing in the waters of the oceans can be visualized when it is realized that the removal of one hundred million tons per year (the approximate annual steel production in the United States) for a million years would reduce the magnesium content of sea water only from 0.13 to 0.12 pct, providing no more magnesium had washed into the sea in the meantime. Not only is magnesium potentially very abundant but it is in addition a very versatile metal and can be shaped and worked by practically all methods known to the art of metal working. It can be cast by sand, die, and the various permanent-mold methods;

Jan 1, 1953

By Francis T. Havard

A Reply to the Discussion by Mr. Francis T. Havard of the Paper by Mr. Henry W. Edwards, which was read at the Atlantic City Meeting, February, 1.904. (Annual Meeting, February, 1905.) MR. HENRY W. EDWARDS, Grand Junction, Colo. (communication to the Secretary) :* Effect of Heat. It should be remembered that the coefficient of expansion of concrete is nearly that of iron; therefore in constructing flues the design must take account of this important detail. The cracking of flues, mentioned by Mr. Havard as having occurred at a temperature of 100° C. and above, . were possibly caused by neglecting to appreciate the extent of the expansion and contraction of the concrete. Effect of Atmospheric Moisture.-The moisture present in the atmosphere is exceedingly injurious to flues of any material, and those made of concrete are no more susceptible than of brick. My experience with flues of the Monier construction, having walls from 1.5 to 2.5 in. thick plastered upon a net-work of iron rods, was unsatisfactory from the standpoint of dura¬bility.

Mar 1, 1905

THE problem of reaction rates in the open-hearth process is essentially that of trying to form a fairly clear picture of the "chemical mechanisms" in the bath. Quantitative data on reaction rates would not be very useful even if they were available; however, what few , approximate data there are, can be used in combination with data given in Chapters XVI and XVII to sketch a picture of the "chemical mechanics" of the open-hearth process that is consistent with essentially all the present available evidence. The result may later be found incorrect in many details but even so it will illustrate certain useful methods for obtaining a clearer understanding of the process. As discussed in the last portion of Chapter XIII chemical reactions in general involve the following factors: 1. The reacting molecules are mixed together in space in such fashion as to favor collisions among them. 2. A certain number of collisions occur per unit time among the reagent molecules, depending on their concentration and on temperature. 3. A certain percentage of these collisions result in reaction, these being the collisions between those molecules possessing at the moment energy levels above certain minimum values. The temperature factor enters mainly through (3), and its effect is very marked. (What is called temperature is really the mean energy content of all the molecules of the substance involved; at any one temperature a certain proportion of the molecules will have much higher energy content than the mean value.) Various reaction rates measured at around room temperatures have been found to be speeded from 1.6 to 4.0 times by an increase of only 15 to 20°F., simply because increasing temperature produces a rapidly increasing percentage of molecules with energy levels above the minimum needed to produce chemical reaction in a collision.

Jan 1, 1944

IT is difficult to judge how much influence the success attained during its first year, 186465, by the School of Mines at Columbia had on developments in education for the mineral industry elsewhere in the immediately subsequent years. The facts are as follows: 1. The Massachusetts Institute of Technology began giving instruction in February 1865, with a mining course included in its curriculum. 2. Early in 1865 the faculty of the Department of Science, Literature and the Arts of the University of Michigan requested permission from the Regents to establish "a course of study to be called the School of Mines . . . Also that the degree of Mining Engineering be conferred on students who should complete the course of study prescribed in the same." A resolution authorizing this was adopted by the Regents on March 28, 1865. 3. Samuel Hooper endowed a Sturgis-Hooper professorship of geology at Harvard in 1865 with the intention of making it a nucleus of a new School of Practical Mining and Geology. 4. Yale appointed Alfred P. Rockwell professor of mining in 1865. 5. Lafayette College appointed Henry S. Osborn professor of mining and metallurgy in 1865. 6. Washington College (as Washington and Lee was then known), rising out of the ashes of Civil War destruction, made a fresh start in 1865, with General Lee as its president, and offered a mining course in the first catalogue thereafter published. 7. Lehigh University, founded in 1866, had a mining curriculum from its beginning. 8. Rensselaer Polytechnic began offering a curriculum in mining and metallurgical engineering in 1867. It would be natural to suppose that these events were a reaction to the success of the school at Columbia, and possibly they

Jan 1, 1941

By E. P. Abrahamson II

The effect of transitiorz element bitzary solid solution additions upon the recrystallization temperature of columbium has been investigated. The elements Mn, Fe, Co, Ni, W, Re, and 0s OWY the yecystallization tempel-aturye, while Ti, V, CY, zr, Mo, Ru, Rh, Pd, Hf, Ta, W, Ir, and Pt mise it. A correlation is kloted between the rate of chatzge of recyystallization tewaperature with atomic hercent solute and the free atom electron configuration of the solute element. The work of Abrahamson and Grant1 has indicated a correlation between the free atom ground-state electron configuration and the change in brittle-ductile transition temperature per atomic percent solute in chromium base alloys. A similar correlation was observed for the change in the recrystallization temperature of iron base alloys by Abrahamson and Blakeney and Abrahamson. It was also observed that the limit of rapid change in recrystallization temperature also Correlated with the electronic configuration of the free solute atom. A further study by Abrahamson4 established the generality of the phenomenon by yielding similar results for vanadium base dilute alloys. It has been inferred that a peri- odicity might be expected with changes in the free atom electron configuration of the solvent element. This study is the third set of transition base metal systems to be studied. It is the object of this and further studies on transitional metal systems to detect any systematic variations in the observed correlation which might contribute to the understanding of the electron interactions which are evidently exhibiting themselves. PROCEDURE All alloys were made using 99.9 pct Cb with 0.030 Ta, 0.016 0, 0.0025 H, 0.003 Mo, 0.021 Fe, 0.005 C, and 0.002 N. The solute elements were 99.9 pct pure. According to the published binary phase diagrams5 and metallographic examinations at X750, all additions were in solid solution. The alloys were arc melted and remelted 6 times in the form of cubic 400-g buttons under an argon atmosphere. They were then hot forged at 1200oC to 0.6-in. diameter, annealed for 3 hr at 1200o under argon, and furnace cooled. The specimens were then machined to 0.400 -in. diameter. Grain size was checked and found to remain essentially constant at 150 i 30 grains per sq mm. The specimens were then cold swaged to 0.187-in. diameter, yielding 46 i 1 pct cold work. All alloys were chemically analyzed for the major solute. Analyses of random samples indicated that the impurity content remained at the values of the starting material. Tungsten contamination was held to 0.007 pet.

Jan 1, 1962

Organization Place Date 1919 American Society of Mechanical Engineers... New York, N. Y. Dec. 2-5 American Institute of Chemical Engineers.... Savannah, Ga. Dec. 3-6 Geological Society of America..: Boston, Mass. Dec. 29-31 American Society of Heating and Ventilating 1920 Engineers New York, N. Y. Jan. Mining and Metallurgical Society of America.. New York, N. Y. Jan. 13 American Institute of Min. and Met. Engineers New York, N. Y. Feb. 16-19 American Ceramic Society Philadelphia, Pa. Feb. 23-26 American Electrochemical Society Boston, Mass. Apr. 8-10* *On Apr. 9, a joint meeting will he held with the A. I. E. E.

Jan 12, 1919

By William H. Grady

FactoRs entering into the market value of coal are its grade, and the cost of labor, material, and capital. Reduction in these costs cannot be expected in the future, and it therefore follows that greater economy in their use must be accomplished if it is desired to hold the present markets; more tons of product per unit must be obtained in a given time from both men and material, and means devised for increasing the percentage of lump and domestic sizes. This paper is presented for the purpose of inviting discussion and stimulating thought in regard to the influence of methods of procedure and plans of mining, upon the quality of coal, the economical use of labor, material, and capital, and the cost of production. Even the better methods of the present day leave much to be desired, and a review of the reasons and necessities for their use may be of value in pointing the way to more economical mining. The writer does not attempt to discuss untried methods of mining, but rather to state clearly and concisely a summary of the results obtained under the several methods of procedure that have been adopted. In some instances a high degree of concentration has been effected, and comparisons of the results obtained with the results of lesser degrees of concentration form an interesting study. It is believed that much may be accomplished in improving the quality, and in the more economical use of labor, material, and capital, by concentration, and it is to concentration in particular that your study is invited. The writer, who has occasion to visit many mines, most of which are under different management, has been inclined to the opinion that improvement has been retarded in many ways and that mining has not as yet been entirely freed from the early-day practices which were forced upon it. Practices resulting in lack of concentration, to which reference will be made, are: The absence of robbing, necessitating the frequent interposition of barrier pillars; lack of system and of proper supervision, resulting in losses of life and coal. These practices could not well be

Jan 1, 1915