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By S. L. Hoyt

The writer has long been interested in seeking an explanation of the upper heat effect in the copper-tin alloys over the a + b range, first described in 1913. These notes are offered, not at all as the final explanation 'of this heat effect, but rather to indicate certain progress which has been made toward establishing what happens over this temperature interval. While working on the thermal analysis of the copper-rich kalchoids (copper-tin-zinc alloys), it was noted that those alloys containing major portions of tin and minor portions of zinc exhibited two marked heat effects, one at about 520' C. and the other at about 600" C., instead of the single effect which is generally observed in either of the two binary series. This matter was discussed with Dr. Guertler, who suggested that a heat effect at about 600" C. in the pure copper-tin alloys might be expected. This led to a more searching examination of the thermal critical points in the pure copper-tin alloys, with the result that a marked, although somewhat weak, heat effect was located at about 600. Somewhat later, this upper heat effect was discussed with Dr. Burgess, and it was requested that the Bureau of Standards make heating and cooling curves of one of these alloys for the purpose of removing any possible doubt as to the actual presence of the heat effect. Results obtained by the Bureau are given in Plate I. In an earlier paper1 differential curves were published showing that the heat effect occurred at constant temperature over the a + B range and increased in magnitude with the amount of B up to a point somewhat above 20 per cent. tin. No heat effect was noticed at this temperature in the eutectoid alloy. The existence of this heat effect seems to require a modification of the present copper-tin diagram in the a + B field, and it has been the object of the work here presented to secure the evidence upon which such a change should be based.

Jan 1, 1919

By H. B. Pulsifer

THE unprecedented high price of zinc ore prevailing through the early months of 1915 caused great activity in the Joplin district of Missouri. The Media mill is conspicuous as one of the first of the new "big mills" of the district. The mill was built over a mine previously worked but abandoned in 1912 because of the leanness of the ore and the large quantity of water encountered. The ore prices prevailing-$100 a ton in June, 1915, as against $50 in 1912-favored the new undertaking. The mill was designed for good recovery so that it might operate in times of depression. In design and equipment, the mill is exclusively local in conception and construction. Former Exploitation The tract of land is a part of the large Guinn holdings; 70 acres are comprised in this particular lot, which is situated just a mile north of the center of Webb City on the Alba line of the Southwest Missouri Electric Railway. The ore lies 242 ft. below the' surface at the top of the knoll which is surrounded by the well-known properties: Black Cat, Ground Floor, Florence, Hurry-Up, Electrical and Mercantile. Since the abandonment, in 1913, of the Yellow Dog. a bit farther to the north, the Black Cat, Ground Floor and Florence workings had been flooded. However, as there was no cut through from this side into the area it was proposed to exploit, it was thought that moderate pumping facilities would take care of the water.

Jan 5, 1917

By Herbert Clark Hoover, Lou Henry Hoover

PREVIOUSLY I have given much information concerning the miners, also I have discussed the choice of localities for mining, for washing sands, and for evaporating waters; further, I described the method of searching for veins. With such matters I was occupied in the second book; now I come to the third book, which is about veins and stringers, and the seams in the rocks1. The term "vein" is sometimes used to indicate canales in the earth, but very often elsewhere by this name I have described that which may be put in vessels2; I now attach a second significance to these words, for by them I mean to designate any mineral substances which the earth keeps hidden within her own deep receptacles.

Jan 1, 1950

By Larry Kaufman, Joan B. Berkowitz-Mattuck, Edward V. Claugherty

The oxidation characteristics of hafnium and zirconiunr diboride were measured between 1200 and 2200'K by a thermal- conductivity method which continuously ttzeasures the rate of reaction of oxygen with the diboride and by a metallographic air oridation method zuhich provides a measure of the total arr7ount of bovide conuerted to oxide for a given time interval. The oxidized specimens obtained from the tl~eritaal-coi~ductitrity method were also examined by quantitatire metal-lographic procedares. The significant results obtained in this investigation reveal that metal-rich compositions of lzafi~iutil diboride proride the most oxidation-resistatzt material up to 2000°K; hafnium diboride is tmre oxidation- resistant titan zirconium diboride at all tempevatures examined; the morphology of the oxide formed on H/B2 and Llie temperature coefficient qi. the oxidation rate constants change at the temperature of ttze monoclinic to tetragonal phase transition] in HfO2; the oxidation of neither HfB2 nor ZrB2, results iN catastrophic Jazlure at lorc. oxygen pressures; and pvefevetztial gvaLti boundary oxidation was not obsevued for either HfBi or ZYB, A comprehensive study of the high-temperature characteristics of refractory transition-metal di-borides is currently in progress. This program has included investigation of the physical, thermal, and thermodynamic properties of TiB2, ZrB2, HfB2, NbB2, and TaB2. In addition, aspects of the synthesis and fabrication of such materials have been studied. In view of the diverse nature of this research, a number of other laboratories have actively participated and contributed specific capabilities for analysis and characterization of these materials. As a consequence, an extensive description of the relevant properties of these compounds has emerged which is central in evaluating their high-temperature (1200" to 2500°K) performance. To date, information on thermodynamic stability, specific heat, and vaporization characteristics,1 hot hardness and electrical resistivity,1, 3 therma1 expansion:'4 and thermal conductivity 1, 5 has been presented. This information has been generated on materials of the highest purity (98.5 to 99.9 wt pct Me + B) and density currently available. Samples fabricated by zone melting6 and high-pressure hot pressing"3'7 techniques have been used to generate suitable specimens for all of the aforementioned studies. dation characteristics of the most oxidation-resistant of these materials, hafnium and zirconium diboride, is presented and a description of the synthesis and the experimental procedures used to prepare and characterize specimens is given. The high-temperature range under consideration (1200" to 2200°K) and the known dependence of oxidation characteristics on sample chemistry, density, and oxidation conditions required a close coupling of the synthesis, fabrication, and evaluation procedures.8 This was accomplished by continual surveillance of chemical composition of starting materials before and after specimen fabrication and by evaluation of density, phase constitution, and microstructural features prior to and after oxidation exposure. I) PROCUREMENT AND CHARACTERIZATION OF STARTING MATERIALS In view of the current state of the art in fabricating refractory boride materials, the methods used in preparing samples for the present study are given in detail as follows: starting materials were purchased in high-purity powder form and fabricated by high-pressure hot pressing into 0.40 by 1.00 in. bars from which oxidation specimens were obtained. The hafnium diboride used in this study was purchased from Wah Chang Corp.; the zirconium diboride from U.S. Borax and Chemical Co. These powders were routinely characterized by quantitative chemical analyses for metal, boron, carbon, oxygen, nitrogen, and iron, by qualitative emission-spectrographic analysis for trace impurities, by X-ray procedures for extraneous phase identification, and by powder densitometry for comparison with X-ray (theoretical) density. Hafnium and zirconium metal and elemental boron were also purchased as high-purity powders and characterized for impurities by emission-spectrographic analyses. The hafnium diboride was procured in three shipments which were designated as HfBl.g7(1), HfB1.88(2A), and HfB2.12(2). The indicated stoichiometry is based on the atomic ratio of total boron to total hafnium; the number in parentheses identifies the shipment number. Shipment 1 was 5 1b, shipment 2A, 1 1b, and shipment 2, 8 1b. The zirconium diboride was procured as a 20-1b shipment and designated as ZrB1.89(1). A small quantity of purified zirconium diboride was also supplied and designated ZrB1, 9(P). The averaged results for chemical analyses which were generally performed according to the procedures set forth in the compilation by KrieGe9 are presented in Table I. Qualitative spectrographic analyses indicated that Ca, Cr, Ti, Si, Zr (in H~B~), and A1 were present at levels between 0.01 and 0.10 wt pct. Other metallic elements were found to be less than 0.01 wt pct. Since it is virtually impossible to purchase these materials in the desired quantities (5 to 20 lb) as single-phase compounds it is necessary to obtain

Jan 1, 1968

Albin, B. R Billings, Mont. '28 Amster, Nathan L 25 Broad St., New York, N. Y. '28 Bache, Jules S 42 Broadway, New York, N. Y. '28 Barrett, C. P 5338 Harper Ave., Chicago, 111. '28 Bayless, William S Russ Bldg., San Francisco, Cal. '28 Bean, Louis, H 60 E. 42nd St., New York, N. Y. '28 Beatty, Ross J Room 604, 6 N. Clark St., Chicago, III. '28 Benwell, Oswald F Hold Mags. '28 Beymer, Albert S., V.P., Keystone National Bank Pittsburgh, Pa. '28 Blumenthal, Hugo 44 Pine St., New York, N. Y. '28 Boettcher. Charles Ideal Cement Bldg., Denver, Colo. '28 Bowlus, Thomas H., Banker, Pres., Allen County State Bank Iola, Ran. '28 Brown, Colvin B Chamber of Commerce, Washington, D. C. '28 Burt, Maxwell Struthers Southern Pines, N. C. '28

Jan 1, 1934

By G. K. Manning, E. R. Stein, E. E. Underwood

Columbium, carbon. and nickel additions were made to iron-base alloys with 20 pct CY. The effects on microstructure, precipitation-hardening characteristics, and High-temperature properties were investigated by means of metallographic, hot-hardness, and magnetic measurements. An austenitic alloy consistilzg of Fe-20Cr-14Ni-0.8C-2.5Cb had higher hot-lzaciness at 1700°F than the other alloys investigated. Its favorable standing is attributed to an enhanced interaction of Cb and Cr4C particles dispersed within a stable austenitic matrix. FOR the past 20 years, cobalt- and nickel-base alloys have been used for the more stringent high-temperature applications because of their excellent creep resistance. Although their performance is quite satisfactory, other base materials must be considered for large tonnage, low-cost applications such as for the automotive gas turbine. Iron-base alloys are also used extensively, but at somewhat lower temperatures, primarily because of the instability of particles or because precipitation occurs at relatively low temperatures. Since unusual stability has been reported for Fe-Cb and Cb-C compounds.1-3 it was hoped that effective amounts of these compounds could be taken into solution at temperatures just below the melting range, then precipitated upon reheating. Actually, strengthening was found to occur by both precipitation hardening in some alloys and by phase transformations in others. Among the alloys investigated, that with the best high-temperature properties owes its strengthening to a combination of carbide particle interaction and a relatively stable austenitic matrix. EXPERIMENTAL PROCEDURES Small preliminary melts of about 100 g were made in a vertical Glotube furnace, using alundum crucibles and an argon atmosphere. Alloys weighing 35 lb were melted in a basic-lined induction furnace, also under argon. The compositions of the alloys are given in Table I. The nickel-free alloys were usually ferritic, while those containing nickel were generally austenitic. Depending upon the particular heat treatments, or the combination of alloying elements, two-phase alloys of ferrite and austenite could be obtained. In the following text, however, the nickel-free or nickel-bearing alloys are referred to simply as either ferritic or austenitic alloys respectively. The small ingots were swaged at 2000°F, in steps, to rods of approximately 3/16-in. diam. The large ingots were forged at 2100°F to 1-in. sq bars. No difficulties were encountered in swaging or forging any of the alloys to as much as 90 pct reduction in area. For heat treating at temperatures above 2000°F, specimens were sealed in quartz tubes under a partial pressure of helium. No special precautions were found to be necessary at lower temperatures. Intermetallic compounds in the preliminary alloys were identified by means of X-ray diffraction measurements. Correlation of these results with micro-structural characteristics (such as color, shape, size, and location) of the compounds aided in their identification. Magnetic susceptibilities were also obtained at room temperature with a Magne Gage instrument after the various heat treatments. To

Jan 1, 1962

By R. W. Snyder, W. H. Guilinger, B. S. Gottfried

Two numerical methods are presented JOT solving the equations Jor one-dimensional, multiphase /low in porous media. The case oF variable physical properties is included in the Formulation, although gravity and capillarity are ignored. Both methods are analyzed mathematically, resulting in upper and lower bounds for the ratio of time step to mesh spacing. The methods are applied to two- and three-phase waterflooding problems in laboratory-size cores, and resulting saturation and pressure distributions and production histories are presented graphically. Results oJ the tuo-phase flow problem are in agreement with the predictions of the Buckley-Leuerett theory. Several three-phase flow problems are presented which consider variations in the water injection rate and changes in the initial oil-and ujater-saturation distributions. The results are different physically from the two- phase case; however, it is shown that the Buckley-Lez~erett theory can accurately predict fluid interlace velocities and displacing-fluid frontal snturations for three-phase flow, providing the correct assumptions are made. The above solutions are used as a basis JOT et~aluuting the numerical methods with respect to machine time requirements and allowable time step for a fixed mesh spacing. INTRODUCTION Considerable progress has been made in recent years in obtaining numerical solutions of the equations for two-phase flow in porous media. Douglas, Blair and Wagner2and McEwenll present different methods for solving the one-dimensional case for incompressible fluids with capillarity (the former using finite differences, the latter with an approach based upon characteristics). Fayers and Sheldon4 and Hovanesian and Fayers8 have extended these studies to include the effects of gravity. West, Garvin and Sheldon, l4 in a pioneer paper, treat linear and radial systems with both capillarity and gravity and they also include the effects of compressibility. Douglas, Peaceman and Rachford3 consider two-dimensional, two-phase, in compressible flow with gravity and capillarity and Blair and Peaceman1 have extended this method to allow for compressible fluids. No one, however, has examined the case of three-phase flow, even for the relatively simple case of one-dimensional flow of incompressible fluids in the absence of gravity and capillarity. In obtaining a numerical technique for simulating forward in situ combustion laboratory experiments, Gottfried5 has developed a method for solving the one-dimensional, compressible flow equations with any number of flowing phases. Gravity and capillarity are not included in the formulation. The method has been used successfully, however, for two- and three-phase problems in a variable-temperature field with sources and sinks. This paper examines the algorithm of Gottfried more critically. Two numerical methods are presented for solving the one-dimensional, multi-phase flow equations with variable physical properties. Both methods are analyzed mathematically, and are used to simulate two- and three-phase waterflooding problems. The numerical solutions are then taken as a basis for comparing the utility of the methods.

Jan 1, 1967

By B. C. Allen, W. D. Kingery

Surface tension and its temperature dependence have been determined for pure liquid Fe, Cu, Co, Ni, and Sn and for Fe-C, Co-C, and Ni-C alloys. The temperature coefficient of surface tension is negative for all these liquids. The surface tension and wetting behavior of tin and tin-titanium alloys on A120,, Si,N,, MoSi,, and Sic, as well as the behavior of titanium-containing nickel alloys on A1 20, have been determined over a wide temperature range. For all the solids investigated titanium additims markedly lower the contact angle. Some limits for the solid-surface energies have been calculated from liquid surface tension and wetting behavior. SURFACE tension and interface energy are important variables in a number of metallurgical and ceramic phenomena, and have been discussed at some length in connection with determining micro-structure of polyphase systems,' solid-state sintering,' thermal etching of grain boundaries, heats of solution and fine powders,'1 grain-growth phenomena,' the mechanical behavior of fine foils and fibers, nucleation, soldering and brazing,' and other phenomenz of academic or practical interest However, until recently few quantitative data have been available for high-temperature systems. Among available data are some indicating positive temperature coefficients for the surface tension of liquid copper,*,11,'2 cast iron,l3 and iron-carbon14 alloys. Although carbon was found to be not surface active in iron at 1570" some preliminary studies had indicated the possibility of a positive temperature coefficient for the eutectic composition at lower temperatures.16 One part of the present study has been largely concerned with determining the temperature coefficient of surface tension for several metals at elevated temperatures, In addition to surface-tension studies, the wetting behavior of alloys containing titanium has been investigated over a wide temperature range. Previous measurements indicated that titanium was selectively adsorbed from nickel at a liquid nickel-solid alumina interface,17 and the use of titanium hydride or titanium-alloy techniques for metal-ceramic soldering is well known. In the present study, previous data have been extended to new alloy systems, and measurements have been carried out with other oxidation-resistant ceramics. EXPERIMENTAL The sessile-drop method was employed to measure liquid surface tension and contact angle between liquid and solid, utilizing apparatus and techniques which have been described previously.'g The shape of a sessile drop depends on equilibrium between forces of surface tension tending to form a spherical surface of minimum area and forces of gravity tending to flatten the drop. Typical sessile drops are shown in Fig. 1. From precise measurements of maximum drop diameter and drop height the surface tension and drop volume were calculated. Four solid materials were employed as supporting plaques for the liquid-metal drops. Aluminum oxide (99.9 pct, J, T. Baker, reagent grade) was pressed and sintered at 1800°C. Molybdenum-disilicide powder (99.0 pct, Electro Metallurgical Co.) was pressed and sintered at 1650°C. Plaques were cut from silicon carbide (99.4 pct, hot-pressed at Alfred University) and silicon nitride (95.1 pct, with Al, Fe, 0 as major impurities, Norton Co.) rods. All plaques were polished, cleaned, and dried prior to use. A number of metals and alloys were employed. Chemical analyses of vacuum-melted ingots of iron, nickel, cobalt (National Research Corp.), commercial nickel-base alloys, electrolytic copper (International Smelting and Refining Co.), and tin (Mal-linckrodt Chemical Works) are given in Table I. Alloys were prepared in the laboratory by vacuum melting the base metal with either titanium hydride (Metal Hydrides, Xnc.) or spectroscopic-grade carbon (National Carbon Corp.). Nickel-titanium alloys contained between 0.001 and 0.005 pct oxygen and the ferromagnetic metal-carbon alloys contained 0.001 pct. Cylindrical metal specimens (1 to 2.5 g) were machined and bevelled at the bottom to insure a uniform advancing contact angle on melting. Before use the samples were acid-etched, cleaned with acetone, and rinsed in petrol ether.

Jan 1, 1960

By C. O. Burgess, W. D. Forgeng

DESPITE the increasing interest in and the technical importance of iron-chromium-manganese alloys, very little published information is available regarding their constitution. F. M. Becket's paper1 in 1930 represents the first correlated effort in the field of these alloys. The paper served particularly to draw attention to the commercial possibilities of iron-rich alloys containing chromium and manganese in balanced proportions. The duplex structure of alloys within the commercial range was briefly discussed, but exposition of their structural constitution was necessarily limited because the physical properties and corrosion resistance of the alloys were the main subjects of the paper. Both prior to and following the publication of F. M. Becket's paper, and at his instigation, an extensive investigation of the constitution of iron-chromium-manganese alloys of commercial purity was in progress at the Union Carbide and Carbon Research Laboratories, Inc. The present paper is based on the results of that investigation. In the last few years, investigations covering various portions of this alloy system have also been made in Europe. W. Koester briefly mentioned the effect of annealing on chromium-manganese steel2 and later3 constructed approximate sections of the iron-chromium-manganese equilibrium diagram. M. Schmidt and H. Legat14 even more recently studied this system, and their article and conclusions are of interest as representing an entirely independent study of a number of iron-chromium-manganese alloys. Koester's sections are shown in Fig. 1. The figures summarize the effect of manganese additions to iron alloys containing 5, 10, 15 and 20 per cent Cr as well as the effect of increasing chromium content on iron alloys containing 3, 8, 20 and 30 per cent Mn. These diagrams, within their composition limits, substantiated in some measure the results of our investigation. However, in our work some differences as regards the position of the mixed alpha-gamma fields were found as compared to Koester's work, and we were able to detect the presence of

Jan 1, 1938

By Oswald J. Heinrich

(Read at the Philadelphia Meeting, February, 1878.) DURING the last twenty years much has been done to investigate and define the Mesozoic formation of the United States along the Atlantic States, as well as in the Territories. The investigations of Professors Hitchcock, Emmons, Hayden, H. D. Rogers, and those now in progress in connection with the geological surveys of Penn-

Jan 1, 1878

By R. W. Shoenberger, J. E. McNulty, B. R. Kuchta, William Spackman, A. A. Terchick, M. E. Hopkins, Norman Schapiro, R. J. Gray, A. F. Duzy, M. P. Corriveau

INTRODUCTION * The United States is fortunate in having abundant reserves of metallurgical-grade coals. Although these coals are better in quality and more accessible than most metallurgical-grade coals found throughout the rest of the world, the best grades of these coals are being depleted. Consequently, more efficient exploration tools and techniques, such as advanced methods of core drilling and logging, correlation by petrography, paleontology, palynology, † physical stratigraphy, and geophysical methods are being used to help assess the extent and quality of the remaining coal reserves. Exploration and assessment of new and existing coal properties become of utmost importance in determining ( 1 ) the economic justification for mining the coal, (2) the optimum design of the preparation plant, and (3) the most effective use of the coal. Recent progress has been made in relating mineral matter, especially pyrite, in coal to geologic conditions and paleogeographic trends. l * Editor's note: Because of the numerous and varied contributions of the associate authors of this chapter, the text does not differentiate between sections prepared by each individual as has been done in other chapters. † Palynology is the science concerned with plant microfossils, especially spores. pollen. and other fossils of microscopic size.

Jan 1, 1979

By William Marsh Baldwin

THE ROLLING OPERATION proper is applied to metals and alloys not only in the production of flat products but also in the production of shapes, rods, wire and even in specialized forms in the production of tubes. The present discussion of rolling copper and copper alloys will be [ ] limited to a consideration of rolling flat products such as strip, sheet, foil, plate, and others. In this case (as in the others listed above), the rolling operation itself is only part of an integrated sequence of operations. In Fig I such a sequence going to make up a brass strip mill is sketched out. It is seen that the rolling opera-

Jan 1, 1948

By J. A. Heskett

NEW ZEALAND is dependent on the outside world for its ferro goods, yet it can boast of at least two well-defined iron-ore deposits; namely, Para Para limonite, 3 Fe203 + 21120 also found as lower hydrated oxides, and Taranaki iron-sand, a combined magnetite and ilmenite, 2FeO + 2Fe203 + FeO + Ti02. The former is of massive variety and the FIG. 1.-VIEW OF WORKS SHOWING IRON-SAND DEPOSITS, ALSO WHARF AND BREAK¬WATER IN THE DISTANCE. latter granular and mixed with various proportions of fine shell and siliceous sand well water-worn. This latter deposit forms the greater portion of the beach sands of the west coast of the North Island of New Zealand. It is so fine that the whole of a sample passed through a sieve of 40 meshes to the inch. The ilmenite cannot be detected by the microscope, as in the titaniferous ores of the Adirondacks, nor can it be magnetically separated, as in the titaniferous ore of Natashkwan, Canada. To all appearances it is a chemical compound of the double oxides of iron and titanium and not a mechanical mixture, as is the ore of the Adirondack deposits.

Jan 8, 1920

By D. J. Reed

Concord coal mine near Bessemer, Ala., built, owned, and operated by Tennessee Coal & Iron Div., U. S. Steel Corp., produces only a metallurgical grade for use as coke in blast furnaces of the division at the Fairfield and Ensley works. Capacity of the operation is approximately 800 tph, half of which is delivered to the coke and coal chemical plant at Fairfield after beneficiation to metallurgical grade coal. The remaining portion of the mine run is rock and refuse removed during preparation. Concord mine coal is hoisted to the surface coal preparation plant by an underground slope conveyor. The slope conveyor is 2449 ft long and has a lift of 729 ft. At time of installation the Concord mine slope conveyor was the largest single conveyor unit ever made with respect to belt horsepower and total lift. After several years it became necessary to determine the cause of slope conveyor cover wear.

Nov 1, 1956

By Hans Lundberg

IN ORDER to comprehend the help and information that may be expected from electrical prospecting, it is necessary to have at least a general knowledge of the methods and principles involved in preparing and interpreting results obtained in the field. Electrical prospecting is rather complicated, both in theory and practice, and in order to make a brief description clear to the practical mining man it has been necessary to idealize and generalize the problems, at the risk of having such simplification criticized by the theoretical man. This simplification must not be misinterpreted as showing a lack of theoretical knowledge. FIG. 1.-FLOW OF CURRENT IN AND AROUND A CONDUCTING BODY. For its operation, electrical prospecting mainly, depends on the fact that most metallic ores conduct an electric current much more readily than barren rocks. If an electric current flows through a block of ground within which a body of chalcopyrite is enclosed in country rock of. schist, the current will find less resistance to its passage through the chalcopyrite than through the schist, even though the passage through the latter be much shorter. This is because the longer path through the chalcopyrite offers less resistance, owing to the superior electrical conductivity of the chalcopyrite (Fig. 1).

Jan 1, 1928

By F. C. Stanford

The work of an engineer is to direct natural forces so that the: bring about the results that he wishes to secure. Heretofore he ha concerned himself chiefly with physical forces and inanimate objects until he has secured a truly marvelous degree of control over them The great problem of the present age is to secure a like degree of know1 edge and control of the human factor. Progress has already been made along this line, but it is only a beginning. Wilhelm Ostwald says tha scientific knowledge enables a man to be a true prophet; but it must be remembered that a good many people do not seem to be able to main tain a high average in prophecy. In short, 'the average of knowledge is not equal to the average needs of the present time, but continually fails to keep pace with it. It has been aptly said that the really essentia need of the period is for more brains; if we only had sufficient knowledg and sagacity we could not only solve all difficulties, but prevent then from arising. This generalization holds good for an industrial organization. Th most vital need of the management is for more brains. The logica course for an engineer in charge of an industrial organization is, therefore to direct whatever forces may be at his command toward the development training, and guiding of all the brains in his organization. This is easie said than done, for it involves the carrying on toward two objective: the maximum of productive work, and the development of the individual who perform it. This is essentially like the rebuilding and enlarging of plant, keeping it in full operation the while. On the other hand, if th aim is merely for maximum production from an organization, withou offering opportunity for development, the final outcome will necessari be like that of a plant that is driven at full capacity without stoppin for repairs or improvements; it eventually becomes so run down th either a complete rebuilding is necessary or else it has to be abandone

Jan 1, 1918

By George Rice

THE A.I.M.E. Ground Movement and Subsidence Committee, pro-posed in 1920, held its first technical meeting in February 1923, under the able chairmanship of Mr. H. G. Moulton. The following list of papers and discussions, indicating the scope of the problems and relation to various conditions and method of mining, were given at that meeting by the distinguished mining engineers: J. Parke Channing, on Subsidence at Miami, Arizona; Howard N. Eavenson, on Mining an Upper Bitu-minous Seam after a Lower Seam Has Been Extracted; J. J. Rutledge, on Subsidence in Two Oklahoma Coal Mines; Benjamin F. Tillson, on Caving Cracks at the Franklin Mine, New Jersey; Dr. F. W. McNair, on the Dome Theory; William Kelly, on disadvantageous effects in Mining and Back-filling Working Upward a Steep-Pitching Iron-ore Bed; Eli T. Conner, on the good results of Back-Filling by Hydraulic Means in Preventing Destructive Subsidence in the Anthracite District; Thomas H. Claggett, on the merit of Systematic Pillar Drawing in Preventing Cracks in an Upper Seam; Henry H. Otto, successful results in the anthracite district in Mining Lower Seams before Upper Seams; Douglas Bunting, on Leading Factors Incident to Successful Mining of an Overlying Seam; Edwin Ludlow, on there being "less damage to buildings when there was complete removal of coal with complete packing than when room and pillar is used without extracting the pillars"; Edward O'Toole on "bumps" in eastern Kentucky mines, which he thought were the result of geologic stresses: H. A. Buehler, on Upheaval of Surface in an Illinois Case in Advance of the Face; and R. Dawson Hall, on The Mechanics of Subsidence from Mining. The author of this paper discussed various Winds of problems of ground movement and subsidence in both metal mining and coal mining; the production of great landslides by workings near an outcrop, as at Turtle Mountain, Alberta, Canada; and general

Jan 1, 1939

By Hugh M. Roberts

In the spring of 1915, then a 30-year old geologist in the employ of the E. J. Longyear Co., of Minneapolis, Minn., I accompanied prospectors to ex- amine outcrops of supposed nickel ore situated a mile or two in from the shore of a lake in the Kenora district of northwestern Ontario. The deposit proved to be bog iron ore containing traces of nickel. We were stormbound there for three days, a circumstance which gave rise to a tale that was told at our fire one night. It seems that Sandy and Jock, two prospectors, were crossing the bay of a large lake in a canoe. They were bucking headwinds; the waves grew higher. Jock called out from the stern, "Sandy, can ye na pray a little." Sandy pressed his knees a little closer into the bow and, between strokes of his paddle, sought for words, which came haltingly, "Save us this time . . . Oh Lord . . . and we promise . . ." when Jock, peering through the spray sang out, "I would na commit yourself, Sandy, I think I see lond ahead."

Jan 1, 1965

By Wayne E. Glenn, R. W. French, Lincoln F. Elkins

The Lance Creek Sundance reservoir provides a case history of ro years performance of a reservoir in which unit operation has permitted effective utilization of gravity drainage augmented by primary pressure control with injection of gas into top structural wells. Detailed performance of the reservoir is presented by means of maps of Well status, reservoir pressure, individual well recovery, etc., and by pool-performance charts. Analysis of reservoir performance indicates only minor water encroachment, so that gravity, injected gas, and expansion of gas are the main oil-expulsive agents. A simplified theory of regional drainage of oil from upstructure location to downstructure location due to gravity is presented and checked by means of comparison of "reservoir" permeability and "well" permeability from the pool performance. Good order of magnitude agreement was obtained. Individual well performance and overall reservoir performance indicate possibility that maintenance of pressure makes ineffective those parts of the reservoir in which permeability is too low to permit effective drainage of oil by action of gravity. Oil from these parts can be recovered only when pressure is reduced locally by selective withdrawal or when overall reservoir pressure is finally reduced.

Jan 1, 1949

By R. M. Caves

High-purity dense tungsten coating is obtained by means of a modified de Boer-van Arkel iodide process using tungsten bromides. The all-glass reaction system is pumped, baked, and sealed (pinched-off) at about 10-7 mm Hg pressure. The bromides then formed in situ are decomposed, depositing tungsten on heated tungsten surfaces. Heating of the specimen is done inductively in a novel arrangement that avoids electrodes of glass-to-metal seals. The tungsten, deposited at specimen temperatures from 2000° to 2800°F and bulb (halide) temperatures of 225" to 725°F, was adherent and uniform, and ranged in thickness to 1/8-in. REFRACTORY metals are of interest at NASA for use in hypersonic aircraft, in rocket engines, and in other thrust devices where very high temperatures are encountered. Tungsten, with a melting point about 6100° F, is potentially very useful for some of these applications. Considerable research on tungsten and its alloys is currently being conducted at the NASA Lewis Research Center. In this tungsten research program, there is need for a method of depositing high-purity, nonporous tungsten coatirlgs. Metallurgical bonding of the coating both to itself and to the substrate is required. In addition, it is necessary to be able to deposit thin, uniform coatings on substrates of a variety of shapes and sizes for laboratory test purposes. A survey of the methods previously used for depositing tungsten coatings indicated that none would likely meet these requirements for high purity, good uniformity, and high density except thermal decomposition of the halides. The method for coating that was selected for investigation was the thermal decomposition of tungsten bromide. This is a variation of the van Arkel and de Boer iodide process established years ago and recently reviewed.1,2 This process is applicable to the transition metals in general. More recently, the application and techniques were extended with chlorine3 and fluorine,4 and included the coating of tungsten. This is believed to be the first report on the use of the bromide for tungsten coating. Bromine was chosen over the other halogens because it promised a lower temperature for tungsten

Jan 1, 1962