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By D. T. Camp, J. A. Clum

WITH experience, the indexing of back-reflection Laue patterns for cubic crystals is usually a straightforward matter. However, for noncubic systems where in general tables of interplanar angles are not available or when inexperienced personnel are involved, properly indexing a crystal is normally a tedious, time-consuming affair. The authors have written a digital-computer program which calculates and prints out a table of interplanar angles for an arbitrary crystal structure and then systematically searches through this table attempting to obtain a consistent fit to back-reflection Laue data supplied by the user. Of course it is possible simply to calculate a desired set of interplanar angles should this be the only requirement. The program was originally written in ALGOL for use on a Control Data G-21 computer and a preliminary version is described elsewhere.' A version in FORTRAN TV which has been run on an IBM 7040 and one in FORTRAN II run on an IBM 1620 are also available. While it is not the purpose of this communication to describe the program in detail, an indication of how the program operates may help one to decide whether the program would be useful under particular circumstances. The hypothetical example chosen involves the indexing of the zinc crystal which has a hexagonal structure and a c/a ratio of 1.856. Input data for this example consists of only nine cards: The first card controls the list of families of planes to be considered. If the Miller indices of a prospective family are (h k 1), the first digit places a limit, in this case 3, on the absolute values of any individual index. The second digit limits the sum (h +k + l + 1), in this case to 5. Therefore the families (013) and (112) are considered but the family (122) is not. All systems, including the hexagonal, are treated using three-digit Miller indices. The second card contains the crystallographic parameters required to define the system. The first digit is 0 if the system is rectangular, that is all angles are 90 deg. If the system is nonrectangular, as in this example, the digit 1 so indicates. The next three values are the lengths of the sides of the reference cell, a, b, c. The final three entries on the card are the angles, a, 8, y between the sides. The digit 0 on the third card indicates that more data follows, the digit 6 shows that a set of six planes is to be indexed, and the value 2.0 indicates that agreement between a tabulated angle and an input angle is considered adequate if their absolute difference is less than 2 deg. The fourth card lists the measured input angles. a12 = 38 deg, a13 = 24 deg, and so forth. More input angles are listed on cards five to eight with the latter giving the input angle 058 = 40 deg. The final card in this series indicates by the digit 1 that no more data is to be processed. The program operates in the following manner: 1) The input data from cards 1 and 2 is read, thereby indicating the crystal system to be examined and the crystallographic parameters of the particular crystal to be indexed. 2) A table of interplanar angles is generated. 3) The input angles contained on cards 4 to 8 are read. 4) The measured input data is systematically compared with the generated table of standard angles. All combinations of poles whose interplanar angles compare with the requisite, specified accuracy are printed out. If no adequate fit is found an indication of this is printed. A typical line from the generated table of interplanar angles is: (001) - (111) 74.92 64.99 It can be shown that in the Miller-Bravais system the first value corresponds to the angles between (0001)-(1121) and the second to that between (0001)-(1011). This particular set of data gave the following result for the planes 1 to 6: (011) (110) (121) (111) (112) (010) The ALGOL version also has the option of simply providing the Greninger-chart coordinates ? and 6

Jan 1, 1967

By A. W. Sommer, H. H. Kellogg

It is shown that SO3-O2 mixtures react with sphalerite at an appreciable rate ill the temperature range of 361° to 527°C to fornz ZnSO4. The rate of reaction follows a parabolle lax. Oxygen, or O2-SO2 mixtures, have a negligible effect on sphalcrite in the same temperatuee range. PRACTICAL roasting of sphalerite is usually performed at 800°C or higher. The calcine is composed of zinc oxide unless the roaster atmosphere contains relatively large amounts of SO2 and the temperature is held to 800oC or lower, in which case zinc sul-fate may also form. Ong, Wadsworth, and assell' have made a careful kinetic study of sphalerite oxidation under these "normal conditions" and have concluded that the rate of the reaction is controlled by the decomposition of an activated complex adsorbed on the sphalerite surface. They found the rate of oxidation to be small at 700°C. Extrapolation of their data to 400°C would indicate an almost negligible rate at this temperature. In our work sphalerite was reacted with air, mixtures of SO2, O2, and N2, and mixtures of SO3, O2, and N2 in the temperature range 361o to 527OC. Negligible rates of oxidation were found, except for the gas mixtures containing SOs. With this latter gas, the oxidation of finely divided sphalerite was fairly rapid and zinc sulfate was the product. Based on the limited evidence available, the rate of sphalerite oxidation by SO3 is postulated to be controlled by gaseous diffusion through pores or cracks in the zinc-sulfate coating. This evidence for the direct reaction of sphalerite and SO, at low temperature may prove of importance to the understanding of zinc-sulfate formation in the dust-collecting equipment usually associated with zinc roasters. The roaster gas carries off fine dust, much of which may be unreacted sphalerite. The temperature in dust-collecting equipment drops from the roaster temperature (about 800°C) through the range of temperature we studied, to ambient temperature. Such dusts are known to contain far larger amounts of zinc sulfate than the primary calcine. It has been assumed in the past that this sulfate is formed by reaction of ZnO dust with SO3 (or SO, plus 0,) in the partly cooled gases. Our work shows that an alternative possibility exists—the direct reaction of SO3 with ZnS dust. EXPERIMENTAL Reaction rates for sphalerite at 350° to 600°C are relatively small so that it was necessary to use finely divided material with a relatively large surface area in order to obtain measureable amounts of reaction. In the preliminary experiments, pure mineral sphalerite, ground to pass a 325-mesh sieve, and chemically precipitated ZnS (in the form of an impalpable powder) were used. In the quantitative rate experiments the ground mineral sphalerite was processed in an Infrasizer to obtain a product with particle size between 9 and 18 µ. The analysis of this material was 66.7 pct Zn, 0.09 pct Fe, and 32.7 pct S (theoretical sphalerite is 67.1 pct Zn, 32.9 pct S). The sized powder was carefully mixed and divided into l-g samples. The apparatus used for the quantitative rate measurements is shown in Fig. 1. For the preliminary experiments the following change was made: The external catalyst furnace (B, C)* was not used. *Letters refer to Fig._______1 .___- Rather, when catalysis of the SO2 + O2 reaction was desired, the glass beads in basket M were replaced by vanadium-oxide pellets. Procedure—A l-g sample of ZnS was placed on a shallow stainless-steel tray, I, and spread evenly to a depth of about 1mm. The tray was placed in the reaction assembly and the assembly inserted in the cold furnace. The furnace tube was flushed with dry argon and then heated to the desired reaction temperature. The temperature was controlled to ±0.5oC. Gas mixtures (O2 + N2 or O2 + SO2) were prepared from tank gases by means of a mixing device identical to that employed by Darken and Gurry.2 The total flow rate of gas was 205 ml per min to point A of Fig. 1. The accuracy of the individual and

Jan 1, 1960

By AIME AIME

TECHNICAL achievement in mining will be rewarded at the forthcoming Annual Meeting of the Institute when the William Lawrence Saunders Gold Medal will be presented to Herman C. Bellinger. Mr, Bellinger was unanimously selected on the first ballot of the Medal Committee. Mr. Bellinger has had notable technical success as vice-president in charge of operations for the Chile Exploration Co., a position he has held since 1920.

Jan 1, 1941

By E. N. Smith, J. C. Redmond

The increasing need for materials capable of withstanding higher operating temperatures for various applications such as gas turbine blading and other parts, rocket nozzles, and many industrial applications, has brought consideration of cemented carbide compositions. The well known usefulness of cemented carbides as tool materials is attributable to their ability to retain their strength and hardness at much higher temperatures than even complex alloys. However, it has been found that the temperatures encountered in cutting operations do not approach by several hundred degrees1 those involved in the applications mentioned above where the interest is in materials possessing strength and resistance to oxidation at temperatures of 1800°F and above. At these latter temperatures, the tool type compositions which are made up essentially of tungsten carbide are found to oxidize very rapidly and to produce oxidation products of a character which offer no protection to the remaining body. As a further consideration, the density of the tungsten carbide type compositions is high, from about 8.0 to 15.0. The refractory metal carbides as a class are the highest melting materials known as shown by Table 1 which summarizes the available data from the literature for the carbides of the elements which are sufficiently available for consideration for these uses. The density is also included in the table, since as mentioned above it is an important consideration in many of the applications for which the materials would be considered. It has been established that in the tool compositions the mechanism of sintering with cobalt is such as to result in a continuous carbide skeleton and that the properties of the sintered composition are thus essen- tially those of the carbide.2 On the hypothesis that this mechanism holds to a greater or less degree in cementing most of the refractory metal carbides with an auxiliary metal, it appears from Table 1 that titanium carbide compositions would offer possibilities for a high temperature material. Titanium carbide has extensive use for supplementing the properties of tungsten carbide in tool compositions. Although the literature contains several references to compositions containing only titanium carbide with an auxiliary metal,3,4,5,6 it may be inferred from the meager data that such compositions were deficient in strength and were considered to have poor oxidation resistance.7 Kieffer, for instance, reports the transverse rupture strength of a hot pressed TiC composition at 100,000 psi as compared to up to 350,000 psi for WC compositions. The work described herein was undertaken to determine the properties of compositions consisting of titanium carbide and an auxiliary metal and to improve the oxidation resistance of such compositions. It appeared possible that the inclusion of one or more other carbides with titanium carbide might improve the oxidation resistance and also that this might be more desirable than other means from the point of view of maintaining the highest possible softening point. Consideration of the available carbides in Table 1 suggests tantalum and columbium carbides because of their high melting points and general refractoriness. The work on improving oxidation resistance was concentrated on the addition of tantalum carbide or mixtures of tantalum and columbium carbide. The auxiliary metals used included cobalt, nickel and iron. It was also desired to learn the general physical properties of these compositions. Experimental Procedure The compositions used in this study were made by the usual powder metallurgy procedure applicable to cemented tungsten carbide compositions. The powdered carbide or carbides and auxiliary metal were milled together out of contact with air. In some cases cemented tungsten carbide balls and in other instances steel balls were used to eliminate any effect of tungsten carbide contamination. A temporary binder, paraffin, was then included in the mix and slugs or ingots were pressed with care to obtain as uniform pressing as possible. The ingots were presintered and the various shapes of test specimens were formed by machining, making the proper allowance for shrinkage during sintering. Thereafter the shapes were sintered in vacuum at temperatures of from 2800 to 3500°F. Final grinding to size was carried out by diamond wheels under coolant. The titanium carbide used contained a minimum of 19.50 pet total carbon and a total of 0.50 pet metallic impurities as indicated by chemical and spectrographic analysis. It was found by X ray diffraction examination with

Jan 1, 1950

By H. Sigurdson, T. V. Cherian, C. H. Moore

The phenomenon of recovery of cold-worked metals is interesting not only because of its practical importance but also because of its fundamental significance in solid state reactions. Although extensive investigations1,2 have already been made in an attempt to discover the mechanics of the recovery process, many of the observations have not yet been satisfactorily correlated to provide a completely consistent model for the process. The wide differences in the recovery rates of various properties can be cited as a typical example of one of the difficulties that are encountered. Frequently, for example, the electrical resistance will have almost completely recovered before any recovery in tensile strength can be detected. Of course, such differences in the recovery rates of different properties might be explained by assuming that each property is a unique function of the work-hardened state, and consequently each property exhibits its own unique recovery rate. The assumption that different properties are uniquely related to the work-hardened state cannot be denied. On the other hand, the properties that recover at different rates often exhibit more or less parallel changes upon work-hardening. This suggests that the microstructural changes attending recovery are not exactly the reverse of the changes attending work-hardening. Several types of imperfections must be postulated in order to account for this apparent anomaly. The different recovery rates for various properties, then, are due to the different recovery rales of the type of imperfection to which each property is most sensitive as well as the unique dependence of each property on the cold- worked state. This concept assumes that a simple model of the work-hardened state consisting only of one type of imperfection, such as Taylor's type of dislocation patterns, is inadequate to cope with the diversified phenomena attending work-hardening and recovery. Although current models for the work-hardened state are not useful for describing all aspects of the recovery process, the general trends of the recovery of each postulated type of imperfection as a function of time and temperature should be at least qualitatively deducible from the rather well developed laws of kinetics of reactions in the solid state. Consequently, recovery data might prove useful for elucidating some aspects of the complexities of the work-hardened state of metals. A preliminary attempt to study work-hardening by investigating recovery rates of cold-worked metals is outlined in the following pages of this report. Experimental Procedure Many properties recover when cold-worked metals are annealed below their recrystallization temperature. Therefore, electrical resistivity, thermal electromotive force, X ray diffraction line widths, X ray diffraction line intensities, elastic spring back, density and other physical and chemical properties have been used to study the recovery process. Major interest, however, has generally been directed toward the recovery of the mechanical properties such as hardness, yield strength, and tensile strength. But a search of the literature suggests that the effect of recovery on the true stress-true strain curve has been neglected, in spite of the current recognition of the fundamental importance of such an investigation. An investigation on the effect of recovery treatment on the true stress-true strain curves in tension, therefore, was undertaken in the present study. Commercially pure aluminum (99. + pet Al) in the form of 0.100 in. thick rolled sheet of 2S-O aluminum alloy was selected as the material for this investigation because rather extensive correlatable data are already available on the recovery of some of its properties. Tensile specimens having a 6 in. long gauge section and a uniform reduced section width of 0.500 in. were machined from the sheet in accordance with a design that has previously been reported.3 All specimens were selected with their axes aligned in the rolling direction. In order to eliminate the effects of previous work-hardening and the effects of machining, the specimens were annealed for 15 min. at 750°F before testing. During tensile testing the loads were measured by means of a proving ring (sensitive to 1/2 lb) in series with the specimen.4 Strains were determined from the extension of a rack and pinion strain gauge sensitive to a strain of + 0.0001. The stress was recorded as the true stress, namely

Jan 1, 1950

By J. L. Taylor, Pol Duwez

THE present knowledge of the Ti-Al system is limited to the portion of the diagram extending from pure aluminum to the intermetallic compound TiAl3' A preliminary investigation of the titanium-rich Ti-A1 alloys revealed that the solubility of aluminum in titanium is quite extensive and that the transformation temperature of titanium is raised by alloying with aluminum. From an X-ray diffraction study of alloys containing up to 75 atomic pct Al (TiAl3), the phase boundaries at 750°C were located as follows: the a titanium solid solution extends from 0 to about 36 atomic pct Al, a two-phase region exists from 36 to 46 atomic pct Al, and an intermediate phase of varying concentration extends from 46 to 62 atomic pct Al. The purpose of the present paper is to describe the crystal structure of this new phase. The alloys were prepared by melting in a helium arc furnace on a water-cooled copper plate, using a furnace essentially the same as that described in ref. 2. The titanium metal was of the iodide type furnished by the New Jersey Zinc Co., and a piece of pure aluminum (99.99 pct) was obtained through the courtesy of the Aluminum Co. of America. After melting, the samples, weighing approximately 5 g, were sealed in evacuated fused silica tubes and homogenized for 4 hr at 1000°C. The specimens were then held for 10 days at 750°C and rapidly cooled to room temperature. Filings were then taken from each sample, sealed in evacuated vials, annealed at 750°C for 4 hr, and rapidly cooled to room temperature by quenching the vials in water. Powder diffraction patterns were obtained with a 14.32 cm diam camera, using K copper radiation filtered through a nickel foil. Structure Determination The X-ray diffraction patterns of the alloys containing 46, 50, 55. 60, and 62 atomic pct Al were identical, except for a slight shift in the positions of the reflections. The alloy containing 55 atomic pct Al was chosen far structure determination. The powder pattern contained 37 reflections and the a, doublets were well resolved in the back-reflection range. The relatively small number of reflections and the sharpness of the pattern were considered as an indication of a simple atomic arrangement in a relatively small unit cell of high symmetry, and an attempt was therefore made to solve the structure without single crystal work. A satisfactory fit was found on a large scale Hull-Davey tetragonal chart for an axial ratio of approximately 1.45. All the reflections were readily indexed and the tentative unit cell dimensions were computed to be a - 2.81 kX, c - 4.07 kX, and c/a = 1.448. The indices (hkl) and the values of d and sin2 A are given in Table I. The agreement between observed and computed sin2 is quite satisfactory. Once the unit cell was known, the details of the structure were readily found. First, it is obvious that the number of atoms per unit cell cannot exceed two, since more than two atoms would lead to a density greater than that of pure titanium. The next logical step is to assume that the two atoms occupy the corner and center of the cell. If this assumption is correct, the structure may be described as follows: space group D1, - P 4/mmm; one titanium atom in a: 000; one aluminum atom in d: 1/2 1/2 1/2: and no extinctions. Assuming this structure to be the correct one. intensities were computed by means of the usual equation: sin2 0 cos 0 where F is the structure factor; 8, the Bragg angle. and p, the multiplicity factor. The calculated values of intensities are compared in Table I with the visually estimated intensities. The agreement is quite satisfactory and the structure is therefore confirmed. The crystal structure of TiAl just described is the same as that of AuCu ordered. The AuCu ordered

Jan 1, 1953

By Stanley M. Moos, Richard Addison

Introduction The Pueblo Viejo gold-silver mine, located in the Dominican Republic, started production in early 1974 processing ores averaging 4 g/t gold and 20 g/t silver at a rate of 7.25 kt/d. The ore milled is a silicified siltstone with average work index of about 8 that occurs as an extensive oxide capping of a primary sulfide ore body. The sulfide ores are refractory to conventional treatment process and extensive research work is now in progress to develop a treatment process for them. The ore deposit has a long history, having been mined by the indigenous Arawak Indians for some time in the early sixteenth century prior to the arrival of the Spanish, and then by the Spaniards. In the early 1950s, Italian engineers attempted to process the sulfide ores. Mining by the Indians and Spanish was abandoned because of low grade and little coarse gold in the oxide ores and by the Italians because of the refractory nature of the sulfide ore. In 1969, Rosario Resources geologists discovered that there existed sufficient reserves of oxide ore for a viable mining operation and the plant was designed, built, and brought into production.

Jan 1, 1981

By U. C. Tainton

THE world-wide continuation of low prices for zinc in 1934 has militated against any striking changes in the position of the metal. The price of zinc in London at the end of the year, about £11 5/8 per long ton, or 2.5c per pound at the existing rate of exchange, is more than 25 per cent below the average price for last year. In these circumstances probably the most significant event of the year was the putting into operation of the new electrolytic plant of the Giesches company at Magdeburg, Germany. This plant is designed to have an initial capacity of 20,000 long tons per year, and it is planned to increase this to 40,000 tons annually. This development is significant not only as indicating a continued swing of zinc metallurgy towards electrolytic methods, but also because it will make Germany virtually independent of foreign sources of zinc. This will mean that the zinc tonnage normally exported to Germany from Belgium and Poland will. become available for other markets, and it is feared may lead to lower prices unless the production of Bel-

Jan 1, 1935

By Robert W. Hunt

(Cleveland meeting, October, 1912.) PERHAPS of all the scientific economic questions which have been claiming the attention of capitalists, metallurgists, manu-facturers, directors of public utilities, and the general public of America, during the last few years, none have been of more importance than the one relating to the wear and safety of steel rails. The discovery of the Bessemer process made possible modern railway development. In that growth, as has generally happened in all progressive movements, ill its department have not remained equally balanced. Iron rails permitted the construction of roadways for the passage of power-driven vehicles. In time the speed and weight of such carriages proved too much for the wearing-qualities of the rails, and the limit of railway capacity seemed to have been reached. Bessemer made his invention, which was soon perfected and developed, especially as related to steel rails, and thereby increased the limit of capacity, acid vastly greater railway progress was, made possible. The Siemens-Martin open-hearth process followed, and was later supplemented by the Thomas-Gilchrist basic improvement. For a time the Bessemer steel rails of commerce Were, more than equal to all that was asked of them, but this did not long continue, as evidenced by the records in our Transactions. Revolutionary changes occurred in the industrial world, and in no part of it more than in steel-rail manufacture. Great and powerful commercial combinations were made, whose financial resources made possible the supplanting of the then most efficient blast-furnaces, steel-works, mid mills, by others of theretofore unimagined capacity. Old traditions and practices of steel-making were wiped away, and, in too many cases, output was apparently the chief aim, with the result that much dissatisfaction with the wear and safety of rails was felt by railway officials, and the general public was concerned as to its safety when traveling. The climatic conditions of the winter

Dec 1, 1912

By C. G. Bieber, J. R. Mihalisin, R. T. Grant

A growing demand for longer service life of gas turbines has placed increasingly rigorous requiret~rents upon superalloys employed for that application. Long-titne testing at high temperature has revealed that phase transformations occur in all superalloys. A common one of particular interest is o formation. Presented here are studies made to identify a and to characterize its formation and effect on properties in three cast nickel-base superalloys—IN 100 alloy, alloy 713C, and alloy 713LC. Methods are discussed by which o can be eliminated or inhibited in IN 100 alloy and alloy 713C. Evidence was obtained to indicate that some types of o may be more detrimental than others. Limitations in the electron vacancy approach to o prevention are pointed out, and it is shown how alternative approaches, such as reducing a complex superalloy matrix to the form of a pseudo-ternary system permitting equilibrium diagram treatment, lead to additional insights into the formation of in these alloys. AROUND 1960. Beiber1 developed IN 100 alloy, which still remains one of the strongest commercially available nickel-base superalloys. The principle used in the design of this alloy was to produce large quantities of y' phase in a y matrix through the use of copious amounts of aluminum and titanium. In 1963, ROSS' showed that when certain heats of this alloy were held for a long time at 1650°F they formed an acicular phase, subsequently identified as a.3 a is a hard and brittle phase first discovered in the Fe-Cr system by Bain and Griffiths.4 They termed it the "B" constituent. Subsequently this same phase was found in other systems, primarily those of the transition elements, and acquired the name "a" by which it is now known. The crystal structure of the a phase was first determined in the Fe-Cr system in 1950.5 It was shown to be tetragonal with a c/a ratio of about 0.52. as is the case with a found in other systems. This characteristic crystal structure is now the means by which a is identified. In superalloys, such as IN 100 alloy. large amounts of o impair the high-temperature creep strength and drastically reduce room-temperature tensile ductility. Discovery of o phase in some heats of IN 100 alloy quickly led to investigations of other superalloys for similar transformations. It was found that many of the stronger, more highly alloyed. super-alloys were indeed susceptible to o formation. This investigation has been concentrated on three commercial alloys: IN 100 alloy, alloy 713C, and alloy 713LC. J.R.MIHALISIN,MemberAIME, and C.G.BIEBER are with The International Nickel Co., Inc., Paul D. Merica Research Laboratory, Sterling Forest, Suffern, N. Y. R. T. GRANT, Member AIME, is with The International Nickel Co., Inc., Pittsburgh, Pa. Manuscript submitted May 22. 1968. IMD A detailed study has been made of the phase transformations and their relation to a formation along with a consideration of electron vacancy approaches for predicting a-forming propensity in these alloys. EXPERIMENTAL PROCEDURE Phase transformations were studied by light and electron microscopy, electron diffraction, microprobe investigations, and X-ray diffraction. Specimens for light micrographic examination were prepared by conventional grinding and polishing followed by etching with glyceregia (2:l HC1/HNO3 + 3 glycerine by volume). Photomicrographs of stress-rupture specimens were taken adjacent to the fracture unless otherwise noted in the text. Negative replicas for electron microscopy were taken from surfaces electropolished with a solution of 15 pct H2SO4 in methanol. For carbon extraction replication, a solution of 10 pct HC1 in methanol was used. A Siemens Elmiskop I was used for all electron microscopy. Selected-area diffraction studies were made at 80 kv using evaporated aluminum for standardizing the patterns. A nondispersive electron microprobe attachment was used to analyze the extracted precipitates chemically. The fluorescent X-rays were recorded using a flow counter containing P10 gas (90 pct Ar-10 pct methane) with a beryllium window and a single-channel pulse-height analyzer. The pulses from the analyzer were passed to a scaler-ratemeter and differential curves of counting rate vs pulse amplitude were obtained. The base line of the analyzer was driven with a synchronous motor at 0.5 v per min and a channel width of 0.5 v. The time for 105 counts was printed out for each 0.5-v increment. The microscope was operated at 80 kv with beam currents of 1 to 20 pa. This equipment detects elements from atomic number 13 to 40. X-ray diffraction studies were usually made on residues electrolytically extracted in 10 pct HC1 in H2O, although in one case a pattern was obtained from an etched surface of a metallographic specimen. A Siemens Crystalloflex IV was used with iron-filtered CoKa radiation. X-ray patterns were recorded using a goniometer speed of : deg per min. The scintillation counter and pulse-height analyzer operated at a channel height of 10 v and a channel width of 12 v. The equipment was calibrated with a powdered gold standard. The residues usually contained a number of phases. several of which could not be found in the ASTM card file. In addition, as is shown for the case of a phase in IN 100 alloy, other phases had a somewhat different lattice parameter from that reported in the ASTM card file, making it difficult to separate and identify constituents by comparison with ASTM d spacings. For these reasons, phases were identified on the basis of the lattice parameter obtained by indexing the ob-

Jan 1, 1969

By Walter E. Lewis

Myriad problems face all of us in the next decade. Vietnam, poverty, and pollution are perhaps the most pres- sing. A lesser one but still vital to us as a Nation is the slow hut apparently relentless extinction of the mining, metallurgical. geological and petroleum engineer. Are we doomed to take our place in the crossword puzzle with the moa. to be defined like it as an "extinct bird"? Or can we reverse the trend perhaps, in the next decade? The plain fact is we are an endangered species, and must resign ourselves to virtual extinction in the 1970's unless the trend is reversed. Probably, many of us have felt the problem will solve itself if left in the in-basket long enough, believing, that the trend will reverse solely on the basis of demand for these disciplines. This approach has not worked up to now, it gives no promise of working in the future, and furthermore, the problem has been in the in-basket much too long. The point is simply this: What can each of us do as an individual, or as part of a company, a State agency, a Federal agency, a university, or an organization such as AIME?

Jan 1, 1970

By AIME AIME

In the uniform of his country for the second time, Harry Phillip Stolz. Chairman of the A.I.M.E. Petroleum Division, holds a commission as Lieutenant-Commander in the Naval Reserve and is attached to the office of Inspector of Naval Petroleum Reserves in California. During World War I he left his studies at Stanford University to join the Army and was granted a commission as Second Lieutenant of Infantry. He remained in the Army Reserve until 1938 when he resigned to accept a commission as a member of the Naval Petroleum Reserves Advisory Board. Born in San Francisco Jan. 29,1899, where his father had lived since 1880, he was in that city during the turbulent year of 1906 where the city was ravaged by fire and earthquake.

Jan 1, 1942

By AIME AIME

FOUK fields of activity are now recognized by the A.I.M.E. in its award of medals for conspicuous achievement: the Saunders medal for mining, the Douglas medal for non- ferrous metallurgy the Lucai medal for petroleum, and the Rand medal for distinguished achievement in the broad field of mining administration including the organization and development of enterprises in all branches of the mineral industry. This last is known officially as the Charles F. Rand Memorial Medal, and it award is made possible through funds supplied by the Charles F. Rand Foundation. Until this year money thus available was used for other special projects, so that the forthcoming presentation of the Rand medal to Robert C. Stanley is notable as being the first time that achievement in mining administration has been thus recognized.

Jan 1, 1940

By AIME AIME

IN A STATEMENT summarizing general conditions in the Federated American Engineering Societies, the executive secretary, L. W. Wallace, expresses the belief that the Federation has made substantial progress. At the annual meeting of the American Engineering Council, to be held in Washington Jan. 5 and 6, this progress will be shown by reports covering activities in many fields. "Unquestionably," says Mr. Wallace, "the Federa¬tion has made favorable and permanent contacts in Washington. Through the, activities of Congress and of the new Federal administration. we have had the opportunity to render some really constructive service. We feel, however, that the great body of engineers are not adequately informed of the organization of the Federation, of its aims and purposes and of its activities.

Jan 1, 1921

By Joseph A. Holmes

Iv all new movements unavoidable misapprehensions arise, which should be cleared away, lest they retard the progress of the movement itself. An impression has gone abroad that the movement for conservation of resources is a new movement. No one knows better than the engineer that this is not the case. Men like Douglas and Raymond and John Fritz and Edison and McDonald, and hosts of others, have preached and practiced conservation as applied to mineral resources throughout a long and useful life-time; and, in general, the work of the engineer and the chemist, both in this and in other countries, has been along the line of continually greater efficiency in the use of all available materials. And the results already accomplished through the efforts of these experts are now saving annually many millions of dollars to the people of the United States in materials and labor. It is true, however, that the need for conservation, that is, for a wiser and more efficient use of the natural resources, has taken on a new life, and is being brought home to the people of the United States in a manner which is awakening public interest and even the public conscience. It is, therefore, both appropriate and fortunate that the engineers, the chemists, and the thinking men of all classes are availing themselves of the present impetus to the movement to emphasize anew the lessons which heretofore they have found it more difficult to impress upon the American public or even upon the captains of industry. Still another of these misapprehensions is to the effect that many of the leaders in the present movement hope to bring about conservation of resources through legislation or execu-

May 1, 1909

BECAUSE of the impetus given to placer mining since the price of gold was advanced to $35, several types of small dredges have made their appearance, especially in the Lincoln and Oroville areas of California. Some of these are known as "doodle bugs," and have been given considerable publicity, though many believe their performance has been overrated and that complete costs of construction and operation, if known would not put them in so favorable a light. Fig. 1 is a doodle bug owned by E. M. Clark and operated near Lincoln, Calif. It is understood that it was abandoned because of inability to handle deep ground. A similar machine that has been operated-profitably by Comstock Placers is shown in Fig. 2.

Jan 1, 1938

By John V. Beall

The forecast of continued growing demand for phosphate, chiefly for fertilizer, has caused a world-wide rush for deposits by a variety of companies many of which have never before mined phosphate rock. The newcomers are diversifying into this growth industry on the strength of certain capabilities. Among these are the availability of investment capital, mining or processing know-how and marketing experience. Product tie-ins have motivated some into the search. Companies with excess sulfuric acid or potential for making it are in this category. This acid is the most commonly used for dissolving phosphate rock to make phosphoric acid. Base metal smelting companies are prime candidates in this field with by-product acid from roasting processes. Producers of "sweet" natural gas, such as those in Louisiana and Texas, have a potential for recovering low cost hydrogen from excess gas production for the manufacture of ammonia, the main source of nitrogen for fertilizer. "Sour" gas producers, such as those in the Canadian fields, are making sulfuric acid that is combined with western U.S. phosphate to make fertilizer materials. The presence of one or two steel companies in the look-see for phosphate deposits is based on by-product ammonia from coke-oven gas.

Jan 10, 1966

By AIME AIME

As already announced, the XCIIId meeting of the Institute will be held at Toronto, beginning July 23, 1907. Hotel Headquarters will be at the King Edward Hotel, in which also the sessions will be held. The Queens, Rossin, Wallen, Iroquois and Palmer are good hotels not far from the King Edward. Members must secure their hotel-accommodations beforehand, by direct correspondence with the hotel they select. For those who neglect this precaution, the Local Committee will doubtless do what it can, but is unable to promise anything. Correspondence concerning this meeting (including notices of intention to attend it) should be addressed hereafter exclusively to Mr. W. G. Miller, Provincial Geologist, Bureau of Mines, Toronto, who is the representative of the Local Committee. The excursion to Cobalt, Lake Tenagami, Sudbury, etc., arranged by that Committee, involves the use of a special Pullman train for meals and lodging. After waiting a reasonable time to hear from members, the Local Committee has made its contract for Pullman cars. According to its latest report, there was still room for additional excursionists. Under this head, application made immediately to Mr. Miller may not be too late. Sessions for the presentation of papers, etc., will be held at the King Edward Hotel on Tuesday afternoon, July 23, and Wednesday morning and afternoon, July 24. The following papers have been accepted: 1. Sonic Reflections on Secrecy in the Arts, by James Douglas, New York, N. Y. .2. The Wilfley Table, by R. H. Richards, Boston, Mass. 3. The Tar-Sands of the Athabaska District, by' Robert Bell, Ottawa, Can. 4. The Occurrence of Nickel in Virginia, by Thomas L. Watson, Blacksburg, Va. 5. Coal-Briquetting in the United States, by E. W. Parker, Washington, D. C.

Jul 1, 1907

By M. S. NORTH

IT may be a far cry from the days of the old horse whim, and it is relatively a long way back to hand production in factories. Modern machinery has made possible deep shaft-sinking, newer methods have increased the recovery of mineral. Technically, excavating and ore dressing have advanced as has mass production and its many ramifications in the manufacture of commercial product. To those of the mining industry who would have us believe that mining and manufacturing are totally different enterprises, it can be said that certain differences do exist. These differences rather than being fundamental are the result of adhering to past practices which were possibly sound years ago but do not measure up today. Differences in managerial control, sales, and distribution, cost finding, etc., are often so pronounced that efforts to compare or contrast are almost futile.

Jan 1, 1930

By Arthur Notman

YEAR ago, the Committee on Mineral Economics ventured to predict a more realistic attitude by the public toward the folly of seeking to have more by making less under the guidance of the Blue Eagle. A unanimous decision of the Supreme Court of the United States has now laid that embattled bird to rest. De rnortuis nil nisi bonum. In spite of dire predictions of disaster to follow its early demise, the metal industries and many others have improved substantially. One could name many indications of that improvement, and on the strength of stock-market activities might assume

Jan 1, 1936