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By A. R. Kaufman, P. Gordon

THE large-scale manufacture and use of uranium in conjunction with the atomic energy development during the war led to a need for knowing the equilibrium diagrams of uranium with various other metals. The alloys of uranium with aluminum and with iron were among the first that were studied for this purpose. Much of the work was done in the manner of a survey since it was necessary to determine the important features of the phase diagrams rather than to obtain completely detailed results. For this reason no attempt was made to locate exactly such features as liquidus lines, solid solubility limits and compound and eutectic compositions. It is believed, however, that there are no great inaccuracies in the diagrams reported here and that no important points were overlooked. Earlier work on alloys of uranium with aluminum and iron is almost nonexistent and in each case is considered to have been of little value by M. Hansen. It is interesting to note, however, that the compound UAl3 was first reported in 1902 by L. Guillet. Experimental Procedure Materials: The uranium used for making most of the aluminum alloys was obtained from material prepared by Metal Hydrides, Inc., and melted in vacuum at M.I.T. Because of the lack of an adequate supply of metal, it was necessary to use material from several different batches and hence it is impossible to state an exact analysis. However, a few results indicated about 0.01 to 0.03 pct iron and probably about 0.03 to 0.05 pct carbon. Toward the end of the work a small amount of metal was obtained from Brown University and from Iowa State College and this was used in determining the transformations in pure metal and in some dilute alloys. All of the aluminum used in this investigation came from a supply of high purity metal (greater than 99.9 pct aluminum) which was obtained through the courtesy of Dr. Mehl of the Carnegie Institute of Technology. The uranium used for making the alloys with iron was produced by the bomb reduction process which has been described by J. Chipman.² This metal, after vacuum melting, contained about 99.9 pct uranium by weight with carbon and iron as the chief impurities. Electrolytic iron containing about 0.012 pct carbon, 0.020 pct nickel and 0.009 pct copper was used in making the melts. Melting Equipment: The melting of the alloys went through a stage of development which culminated in the use of beryllia or beryllia-lined crucibles and in the use of high frequency heating in either vacuum or in an atmosphere of argon. It was found that uranium at a few hundred degrees above its melting point would pick up aluminum and to a lesser extent silicon from an alundum thimble while aluminum above 1000°C would extract silicon from the impure alundum. No reaction of either metal with beryllia was noted at temperatures as high as 1800°C. The distillation of aluminum from the aluminum-rich alloys was quite troublesome at temperatures above about 1300°C and was only partially avoided by the use of argon instead of vacuum. Melting in resistance furnaces,

Jan 1, 1951

By William E. Ford, Edward Salisbury Dana

This section includes one distinct group, the Stibnite Group, to which orpiment is related; the other species included stand alone. Pyr., etc. - In the closed tube melts and gives a dark red liquid when hot and a red- dish yellow solid when cold; in the open tube (if heated ver slow? ) sulphurous fumes, and a white crystalline sublimate of arsenic trioxide. B.B. on ciarcoaTburm with a blue Hame, emitting arsenical and sulphurous odors. Soluble in caustic alkalies. Artif. - Realgar is frequently noted as a sublimation product from furnaces roasting ores of arsenic. Crystals are produced when arsenic sulphide is heated in a sealed tube with a solution of sodium bicarbonate. Obs. - Realgar occurs usually in veins associated with silver and lead ores. It has been found in volcanic regions as a sublimation~duct. It has also been noted as a deposit from hot spring waters. It is often rtasociate wlth orplment. It occurs at Felsi5bBnya, Kapnik and NagyAg, Hungary; Allchar, Macedonia. Binnental, Switzerland, in dolomite. In the United States, at Mercur, Utah; in the Norris Geyser Basin, Yellowstone Park, as a deposition from the hot waters. Found at the Monte Cristo millin district, Snohomish Co., Washington: the namerealga7 is from the Arabic, Rahj af gh&r,powder of the mine. Use. - Was used in fireworks to give a brilliant white light when mixed with saltpeter and ignited. The artificial material is now used for this purpose.

Jan 1, 1922

By G. W. Jones

THIS paper describes experiments in which eight test samples of gelatin dynamite were fired in three different types of apparatus and the quantity and composition of the gaseous products of detonation determined. The special dynamites were so prepared that the oxygen balance of the samples varied from -35.0 to +6.0 g. per 100 g. of explosive, including the wrapper. By means of this graded series of explosives, the relation between oxygen balance and gaseous products of detonation could be studied explicitly. The effect of varying oxygen balance on explosive strength has been discussed in another paper.1 The apparatus employed in the work described in the present paper included (1) the Bichel gage, a steel bomb of 15-1. volume; (2) the Crawshaw-Jones confined detonation apparatus, a steel cannon from which the explosive is fired into a pipe of 90-1. volume; and (3) the Hercules tank, an apparatus in which the explosive is confined in a quartz block which is placed in a steel tank of about 4500-1. volume. A full description of the apparatus is given later. VARIABLES AFFECTING COMPOSITION OF DETONATION PRODUCTS The character of the detonation products of commercial explosives is governed in part by the same factors that affect the combustion products from explosive mixtures of air with gases or vapors. In either case, combustible materials-namely, carbon, hydrogen, and sometimes sulfur-are present and combined variously. In an exploding gas mixture the combustibles are oxidized by oxygen in the admixed air, whereas with explosives the necessary oxygen is provided by oxygen-carrying materials in the explosive ingredients.

Jan 1, 1928

By James G. Blaine, David A. Summers, L. John Tyler

There has been a considerable amount of research developed which shows that the close contour cutting of an excavation prior to removal of the central core will increase ground stability while concommitantly, reducing the number and size of blastholes required to create the excavation. To date, the industrial development of this technique has however, centered on the development of equipment based on simple cutter movement and mechanical rock cutting. The advent of reliable field operable high pressure waterjet cutting equipment with the very low reactive force required to hold the head in position has opened the way for a much smaller and more manueverable system. The advent of small, micro-computers allows the programming of accurate profiles for cutting tools on excavation equipment. The combination of these two technologies will allow the generation of complex as well as simple, excavation profiles and lead to the potential pre-support of the opening before major excavation is completed. A brief description of the necessary components and their functions is encorporated in the initial prototype design as given.

Jan 1, 1984

By E. G. Leonardon, D. C. McCann

The search for oil has required, and without a doubt supplies, a tremendous amount of information on the structure, composition, physical properties, and history of sedimentary rocks. The earliest and most complete source of knowledge is the sample or core of the rock itself, the uses of which are well known. The purpose of this paper is primarily to discuss a new method for obtaining these cores, and to illustrate its use in connection with electrical logs. Most cores have been obtained through a special adaptation of rotary drilling, and the results have been remarkably good, considering the mechanical problems involved. Unfortunately, because of the time and expense, this method cannot be used for the entire length of the drill hole. Even though ingenious contrivances have been evolved in order to reduce the time spent in round trips, such as wire-line coring equipment, mechanical coring still remains too expensive to be carried out continuously. In practice, therefore, one is finally compelled to estimate the probable depths of the more interesting horizons and, allowing a wide margin of safety, to core through those sections only. It is true also that interesting results have been obtained by examining the cuttings brought to the surface by the mud circulated in the well during the process of drilling. Be that as it may, the inescapable fact remains that key horizons may be passed inadvertently, for one reason or another, while the drilling operations are being performed. The only continuous record of the formations encountered is that furnished by electrical surveys. Obviously, it would be desirable to make the electrical survey first and to take the samples from the wall of the hole according to the indications on the electrical log. In this way, it would be possible to core only the exact sections desired, eliminating the otherwise inevitable estimates as to the point at which to start coring, and thereby reducing to a minimum this expensive operation. At the same time this method would provide a maximum of useful samples. A device for taking samples of the formation from the walls of a hole therefore offers the possibility of recovering cores from zones otherwise lost as a source of this type of information. Furthermore, by coring

Jan 1, 1939

By E. G. Leonardon, D. C. McCann

The search for oil has required, and without a doubt supplies, a tremendous amount of information on the structure, composition, physical properties, and history of sedimentary rocks. The earliest and most complete source of knowledge is the sample or core of the rock itself, the uses of which are well known. The purpose of this paper is primarily to discuss a new method for obtaining these cores, and to illustrate its use in connection with electrical logs. Most cores have been obtained through a special adaptation of rotary drilling, and the results have been remarkably good, considering the mechanical problems involved. Unfortunately, because of the time and expense, this method cannot be used for the entire length of the drill hole. Even though ingenious contrivances have been evolved in order to reduce the time spent in round trips, such as wire-line coring equipment, mechanical coring still remains too expensive to be carried out continuously. In practice, therefore, one is finally compelled to estimate the probable depths of the more interesting horizons and, allowing a wide margin of safety, to core through those sections only. It is true also that interesting results have been obtained by examining the cuttings brought to the surface by the mud circulated in the well during the process of drilling. Be that as it may, the inescapable fact remains that key horizons may be passed inadvertently, for one reason or another, while the drilling operations are being performed. The only continuous record of the formations encountered is that furnished by electrical surveys. Obviously, it would be desirable to make the electrical survey first and to take the samples from the wall of the hole according to the indications on the electrical log. In this way, it would be possible to core only the exact sections desired, eliminating the otherwise inevitable estimates as to the point at which to start coring, and thereby reducing to a minimum this expensive operation. At the same time this method would provide a maximum of useful samples. A device for taking samples of the formation from the walls of a hole therefore offers the possibility of recovering cores from zones otherwise lost as a source of this type of information. Furthermore, by coring

Jan 1, 1939

By Frank Clemes Smith

The study of the so-called refractory gold-ores of the Potsdam sandstone, ores which are probably of wider occurrence and of much greater economic importance in the Black Hills than is generally supposed, has led the writer to formulate in the present paper some of the results obtained in the course of a special examination of these particular ores, conducted at the State School of Mines at Rapid City, So. Dak. Various circumstances have interrupted the work, and it will easily be seen that relatively little has yet been accomplished; but it is hoped that this little may be of sufficient interest to justify a later supplement. Tellurium, discovered by Muller von Reichenstein in 1781, is generally classed as a very rare metal; it is further mentioned by one of our late writers as " of comparatively little importance," and as obtained from its ores by a " complicated process.'' Concerning its rarity, we have some trustworthy evidence below. Its commercial importance, particularly in connection with electrical appliances, has been passed upon by Mr. Edison ; * and it is certain that, in some metallurgical processes for the treatment of gold- and silver-ores, it may be saved as a byproduct at a relatively reasonable expense. The importance of tellurium as a mineralizing agent is emphasized by the remarks of one of our leading metallurgists,jwho, in his own practice and by a wide series of experiments, has found its occurrence to be much more general than has been supposed. Recently the same writer has discussed the occurrence of tellurides and oxidized tellurium compounds in the gold-ores of Cripple Creek, Colo., and in those of the Black

Jan 1, 1897

By P. L. Russell

The use of nuclear explosives for excavation has been demonstrated to be feasible and practical. Application of nuclear explosives for overburden removal from large ore deposits appears to offer economic advantages over present methods, but under the present pricing schedule, high-yield devices must be used to obtain an economic advantage. The use of nuclear explosives presents problems not inherent in the use of conventional explosives, and thus they can be used only in areas where large explosions and associated phenomena can be tolerated. Stripping of coal with nuclear explosives does not appear practical at this time, but stripping overburden from copper or iron ore deposits may be a potential use. Even here, however, the use of nuclear explosives would require isolation, favorable topography, favorable ground-water conditions, and a low population density. If these basic requirements can be met, the use of nuclear explosives for overburden removal would offer both economic and time advantages. The possibility of using nuclear explosives for peaceful purposes was a subject for speculation as early as 1945. The PLOWSHARE Program was formally established by the AEC in June 1957 for the purpose of developing and demonstrating peaceful applications for nuclear explosives. The technical direction of the program is the responsibility of the Lawrence Radiation Laboratory, Livermore, Calif. Mining and excavation were two fields that received early consideration as areas in which nuclear explosives might be used. Knowledge gained from underground weapons testing increased this possibility, and the development of the thermonuclear device which has a small fission-to-fission ratio, reduced the hazard of radiation, and spurred interest. Nuclear explosives appear to have the greatest potential in the following mining operations: 1.— Surface Mining a) Stripping of waste for open-pit excavation b) Breaking of ore in open-pit mining c) Quarrying d) Blasting for production of aggregate, riprap, etc. 2. — Underground Mining a) Block caving application b) Crushing of ore for in-situ leaching, etc. c) Preparation of underground waste disposal areas Of the potential applications, excavation is perhaps the most obvious and the best understood, and probably the most practical for use in the near future. Large quantities of rock and earth can be moved by proper emplacement of nuclear explosives, but economic and practical relationship must be determined between the known capabilities of nuclear explosives and the required excavating to remove overburden. REMOVING OVERBURDEN IN OPEN-PIT MINING Removing the overburden is one of the largest jobs in open-pit mining. In 1960 open-pit mines produced approximately 130 million tons of coal, 108 million tons of copper ore, and 135 million tons of iron ore. To obtain this much production, an estimated 3-billion tons of overburden were removed from the coal, 216 million tons from the copper ore, and 135 million tons from the iron ore. These figures do not include the initial stripping required before ore production. For example, the ASARCO Mission mine started stripping operations in August 1959 and by mid-November 1961 had removed 46.3 million tons of material including 1.2 million tons of ore.* Initial excavation of this type offers the most favorable conditions for utilizing the earth-moving ability of nuclear explosives. EXPLOSIVE CASTING FOR REMOVING OVERBURDEN The use of explosives to remove overburden is not a new idea. Conventional explosives have been used for this purpose for many years with varying degrees of success. Several small coal strip operators have used this idea to increase production. At these mines about one-third or more of the overburden is thrown by explosives across the pit and onto spoil piles. The additional costs of drilling more blast holes and more explosives are more than compensated for by a reduction in the time required to uncover the coal, and by an increase in coal production.

Jan 1, 1964

NEW MEMBERS The following list comprises the names of those persons who became members during the period Aug. 10 to Sept. 10, 1914: Members ALLEY, HARRY MCCAMMON, Mill Foreman .... Churchill Mining Co., Wonder,2 Nev. AMBLER, J. OWEN, Met..; ... Calumet and Arizona Mining Co., Douglas, Ariz. ANDERSON, JAMES WILLOUGHBY, Duell, Warfield and Duell, 2 Rector St., New York, N. Y. ANTISELL, FRANK L., Asst. Supt Raritan Copper Works, Perth Amboy, N. J. CARRINGTON, FRANK GAMBLE, Sec'y and Asst. Mgr., Standard Foundry Co., Anniston, Ala. CONKEY, CHARLES ROLLAND, Structural Draftsman, Barnett McQueen Co., Ft. William, Ont., Canada. COOK, PAUL RICHARDSON, Mill Shift Boss, Buckhorn Mill and Cyanide Plant, Buckhorn. Nev.

Jan 10, 1914

By Willis H. Carrier

PARTICULAR interest in the ventilation of deep mines, especially those in South Africa, has been created by a very complete system of cooling of the world's deepest mine, the Turf shaft of the Robinson Deep in Johannesburg. The writer visited this mine in January, 1936, and again in 1937. During these visits and subsequently, a considerable part of the theory involved in rock cooling in tunnels was developed and this has been checked by practical observations of the rates of rock cooling made within mines. The purpose of this paper is to set forth the method of attack of the mine problem. The cooling or air conditioning of mines by the use of mechanical refrigeration was not wholly new 1-5 when the Robinson Deep installation was made. The first mine to be cooled was the Morro Velho mine, in Brazil. The first installation in this mine was put into operation in December 1920, the refrigerant being ammonia.5 The surface cooling gave considerable benefit but it proved inadequate as greater depths were reached, therefore in 1929 two centrifugal refrigerating machines were installed at the 6000-ft. level. These were used in conjunction with the surface cooling system to furnish additional cooling at the lower levels. This later installation used Carrene as a refrigerant. This nonflammable refrigerant, having a boiling point of 104º at sea level, insured reasonable safety, since all parts of the machine operated at subatmospheric pressure. Very favorable reports have been received on the effectiveness of this installation, but no recent data are available. An interesting feature of that plant is that the condenser water is cooled by spraying it into the exhaust air from the mine at the base of the ventilation upcast, which permits the water to be cooled within a few degrees of the wet-bulb temperature of the air entering the upcast, and the only water that has to be supplied for condensing purposes is that lost by evaporation, or about 0.5 per cent of the volume circulating through the condenser. This plan affords an ideal means for the removal of the heat load from the refrigerating system, and of course also from the mine itself. In many mines, however, especially those in South Africa, there is no

Jan 1, 1938

The Anglovaal Group has released details concerning its new processes for recovering platinum group metals, stating that the Group's system, which involves batch processing and precipitation methods for these metals (PGM's), leads to faster recovery times, increased recoveries, and higher purities than the conventional process. Insofar as South Africa's Merensky Reef is concerned, the Anglovaal method of recovering palladium first (as opposed to platinum in the conventional process) enables it to use a much simpler process in the subsequent recovery of platinum and other metals. Because the processes give cleaner separations, the volume of material to be recirculated -and therefore the total volume of material in the recovery circuits- is reduced substantially.

Jan 3, 1976

By Z. T. Bieniawski

Tunneling in coal mines includes driving the main haulageways or roadways which serve as the development entries. Although constituting the lifelines of these mines, little attention has been paid to development entries in the United States in terms of systematic pre-construction planning and design. Coal mine tunnels, as the terminology is used in Europe and elsewhere, are understood in the United States to be the main development entries, either in room-and-pillar mining or in longwall mining. These development entries are not tunnels in the traditional sense since they usually are of a multi-entry type involving entries and cross-cuts, and their intersections. Thus, the design of coal mine tunnels is intertwined with the design of coal pillars. This paper summarizes the results of a three-year research project aimed at improving the design of development entries in U.S. coal mining. A design approach has been developed for this purpose and design procedures for roof support in main entries and for pillar sizing are proposed.

Jan 1, 1984

By J. M. McDowell

A study has been made to deter~r~irre how the behavior of a water drivee reservoir changes as a function of the permeability of the formation and as a function of the size of the aquifer. The effect of pressure maintenance programs on the rote of nat11rn1 water influx is also studied, (IS well as the influence on the influx of the position of water injection we1ls with reference to the oil-water contact. The results are determined by the use of an electrical reservoir analyzer and are plotted as families of curves of pressure, natural water influx, and water injection vs time or cumulalive production. Two size aquifers are studided. One is limited with a 36-inile radius, and the, other approximates an infinite reservoir. The field remains the same in all respects for the completed. study except that the permeability is changed to agree with that assumed for the aquifer. 1 N TR ODUCTI ON this study was undertaken in -dcr to determine how the pres- sure decline and water influx of a water drive field would change as a function of the rate of fluid withdrawals, as a function of the permeability of the formation, and as a function of the size of the aquifer. The effect of pressure maintenance programs on the rate of natural water influx was also studied as was the position of water injection wells with reference to the oil-water contact. The information has been determined by the use of an electrical reservoir analyzer1, sometimes referred to as a Carter type analyzer. This instrument is an analog type computer which can be set up to represent a water-drive oil field. It can reproduce the past performance of the field in terms of analogous electrical quantities when the proper circuit analog of resistors and condensers has been determined, also, it can determine the future behavior for any method of production which may be selected, or permit the comparison among several different methods. Although most applications of the reservoir analyzer"" have been to thc study of specific field performance, it is intended to use the analyzer here to help understand how various reservoir characteristics effect the final performance of the field and to sec under what conditions water injection will be of benefit and to what extent. Within the oil industry the performance of water-drive reservoirs was first described analytically by LV. Hurst' and M. Muskat2 for certain types of boundary conditions. The solutions of the equations developed involved products of exponential functions and Bessel functions. Later publications by Hurst4 and van Ever-clingen" and the hooks of Muskat6 gave further information on reservoirs with other boundary conditions. They also presented rather extensive curves and tables to help evaluate the analytical expressions involved. A rccent series of publications by Chatas. bascd on the work of Hurst and van Everdingen, gives quite complete charts and tables of data to evaluate the pressure decline or water influx in infinite or limited radial reservoirs. and in linear reservoirs. The curves in all of these publications are given in dimensionless form

Jan 1, 1956

By E. S. Davenport, R. J. Hafsten, R. A. Grange

The influence of austenite grain size upon the hardenability of steel is now fairly well understood; for a given austenite, increasing the grain size increases the depth of hardening, and, since the latter is related to the fundamental transformation behavior of austenite, it follows that austenite decomposition must, in general, be retarded by increasing grain size. To date, very little quantitative information bearing directly on the effect of austenite grain size upon the progress and result of isothermal transformation has been published. Davenport and Bain,' and Zimmerman, Aborn and Bain2 have shown that the transformation is definitely relarded in hypereutectoid plain carbon steels at temperatures near and above the upper region of rapid transformation (Ar') when the austenite grains are increased in size. More recently, Griffiths. Pfeil and Allen3 investigated the effect of a series of different heating (austenitizing) temperatures upon the progress of isothermal transformation at 1245°F. (675°C.) and 745ºF. (395°C.) in a medium carbon, low-alloy steel; while they reported no measurements of the austenite grain size, their results suggest that increase in grain size retards austenite transformation at 1245ºF. (675°C), but has no appreciable effect at 745°F (395°C.). The present paper deals with the results of a study of the isothermal transformation of austenite in a single commercial alloy steel in which a fine-grained or a coarsegrained state was induced by appropriate selection of austenitizing temperature. The data are presented in the form of isothermal transformation diagrams, which clearly show that coarsening the grains lessens the rate of transformation of austenite to proeutectoid ferrite and pearlite—that is, at temperature levels above about 1000°F. (540°C.)—but is without significant effect at lower temperatures where the transformation product is bainite or martensite. It is to he presumed that the foregoing statement would be valid, at least in principle, for many other grades of steel; it confirms again that the mechanism of transformation to a pearlitic structure is fundamentally different from that to an acicular structure. A number of related observations were made, which seem to throw some light on the transformation process as it takes place in alloy steels, particularly at temperature levels in the vicinity of 1000ºF. (540°C.), where the transition from lamellar to acicular structures occurs. These data are discussed briefly in the belief that they may lead to a clearer understanding of this aspect of the subject. Material and Experimental Procedure The material investigated was a cornmercial grade of S.A.E. 4140 steel, the composition of which was as follows: 0.37 per cent C, 0.77 per cent Mn, 0.98 per cent Cr and 0.21 per cent Mo. It was hot-rolled to a 1 1/8-in. round bar and normalized by air-cooling from 1800°F. (980°C.).

Jan 1, 1941

By R. J. Hafsten, E. S. Davenport, R. A. Grange

The influence of austenite grain size upon the hardenability of steel is now fairly well understood; for a given austenite, increasing the grain size increases the depth of hardening, and, since the latter is related to the fundamental transformation behavior of austenite, it follows that austenite decomposition must, in general, be retarded by increasing grain size. To date, very little quantitative information bearing directly on the effect of austenite grain size upon the progress and result of isothermal transformation has been published. Davenport and Bain,' and Zimmerman, Aborn and Bain2 have shown that the transformation is definitely relarded in hypereutectoid plain carbon steels at temperatures near and above the upper region of rapid transformation (Ar') when the austenite grains are increased in size. More recently, Griffiths. Pfeil and Allen3 investigated the effect of a series of different heating (austenitizing) temperatures upon the progress of isothermal transformation at 1245°F. (675°C.) and 745ºF. (395°C.) in a medium carbon, low-alloy steel; while they reported no measurements of the austenite grain size, their results suggest that increase in grain size retards austenite transformation at 1245ºF. (675°C), but has no appreciable effect at 745°F (395°C.). The present paper deals with the results of a study of the isothermal transformation of austenite in a single commercial alloy steel in which a fine-grained or a coarsegrained state was induced by appropriate selection of austenitizing temperature. The data are presented in the form of isothermal transformation diagrams, which clearly show that coarsening the grains lessens the rate of transformation of austenite to proeutectoid ferrite and pearlite—that is, at temperature levels above about 1000°F. (540°C.)—but is without significant effect at lower temperatures where the transformation product is bainite or martensite. It is to he presumed that the foregoing statement would be valid, at least in principle, for many other grades of steel; it confirms again that the mechanism of transformation to a pearlitic structure is fundamentally different from that to an acicular structure. A number of related observations were made, which seem to throw some light on the transformation process as it takes place in alloy steels, particularly at temperature levels in the vicinity of 1000ºF. (540°C.), where the transition from lamellar to acicular structures occurs. These data are discussed briefly in the belief that they may lead to a clearer understanding of this aspect of the subject. Material and Experimental Procedure The material investigated was a cornmercial grade of S.A.E. 4140 steel, the composition of which was as follows: 0.37 per cent C, 0.77 per cent Mn, 0.98 per cent Cr and 0.21 per cent Mo. It was hot-rolled to a 1 1/8-in. round bar and normalized by air-cooling from 1800°F. (980°C.).

Jan 1, 1941

By Richard S. McCaffery, Morrison B. Yung

While assaying some copper carbonate ore from the Frazer claims, Similakameen, B. C., I noticed that on parting the gold button a deep orange solution was formed. The button gave off pink bands in the nitric acid, which became deep orange at a short distance from it; and as it traveled over the surface of the porcelain dish, it left a deep orange track behind. As the button brightened in the cupel, it appeared to have a bronze color; but I have since found that when amarillium is in large excess of the gold, the button is a very dark gray. The button parted easily. To the orange solution I added a salt (NaCl) solution, shook in a silver testbottle, and filtered. With H2S I obtained a precipitate, which I supposed due to platinum. However, on further tests, it did

Jan 1, 1903

By William D. Klopp

A study was conducted of the tensile and creep properties of are-melted and electron-beam-melted tungsten over the temperature range 2250° to 4140°F. The tensile and creep strengths vary with pain size, the finer -grained materials being stronger. The activation energy for transient creep at 2250° to 3500°F is 95,000 cal per (g)(mole), while that for steady creep at 3300o to 4000°F is 141,000 cal per (g)(mole). At 2875o to 3300°F the apparent activation energy for steady creep decreased with decreasing temperature. It is suggested that cross slip is rate controlling during transient creep, while dislocation climb is rate controlling during steady creep above 3300° F. ALTHOUGH considerable data have been generated on the high-temperature tensile properties of powder-metallurgy tungsten,1 relative few data have been published on the properties of are-melted2 or electron-beam melted tungsten.3 Furthermore, the available data show a fairly large amount of scatter at high temperatures. The effects of structure and purity have not yet been defined, aside from observations that high-purity electron-beam (EB)-melted tungsten3 and single-crystal-plasma-flame tungsten4 are weaker than less pure powder-metallurgy tungsten. The creep behavior of powder-metallurgy tungsten has been studied, but no data are available on the creep behavior of tungsten consolidated by melting. Green5 found that powder-metallurgy tungsten exhibited linear creep at 4082° to 5072°F with an activation energy of 160,000 cal per (g) (mole). The similarity of this activation energy to that of 153,000 cal per (g)(mole) for volume self-diffusion6 suggests that recovery of strain hardening by dislocation climb is rate controlling in this temperature range. In studies at 4800°F, Sutherland and Klopp7 concluded that grain size significantly affected the creep behavior of commercial powder-metallurgy materials. This grain-size effect was suggested by sherby,8 although the opposite relation had been reported for aluminum.' The purpose of the present study was twofold: first, to provide baseline data on high-temperature tensile and creep properties of are-melted and EB-melted tungsten for concurrent tungsten alloy studies, and, second, to determine the phenomenolo-gical effects of structural and purity variables on the high - temperature mechanical properties of tungsten. EXPERIMENTAL The are-melted tungsten materials were prepared by melting sintered 1-1/4-in.-diam electrodes into 2-1/2-in.-diam by 5-in.-long ingots. The are-melting facility has been described previously.' Eight ingots were melted, machined, and hot-extruded at

Jan 1, 1965

By Herbert Kynor

BY THE term mechanical mining is meant that operation, or series of operations, that replace the hand methods of mining. The first undercutting machine to operate in anthracite was placed in the Butler mine of the Hillside Coal & Iron Co., Dec. 23, 1910, by the Sullivan Machinery Co. The first Jackhamer used in the anthracite field was installed at the Wadesville colliery of the Philadelphia & Reading Coal & Iron Co. in Oct., 1912, by the Ingersoll-Rand Co. The first longwall conveyor was installed at the Dodge mines of the Delaware, Lackawanna, & Western Coal Co. in March, 1912. The first mechanical scraper equipment was installed in the Seneca mines of the Lehigh Valley Coal Co. in January, 1914. The amount of anthracite mechanically mined since the first mining machine was installed in 1910a is as follows: PENNA. COAL Co. D. L. & W., SCRANTON TEMPLE HUDSON YEAR AND HILL- TONS COAL Co., COAL CO., COAL CO., TOTAL. SIDE COAL TONS TONS TONS TONS AND IRON, TONS 1920 372,737b 367,000d 322,892 74,127 371,878 1,508,634 1919 950,786 no record 306,616 81,575 319,356 1,658,333c 1918 917,778 744,966 24,880 44,756 288,781 2,021,161 1917 757,940 838,800 5,050 57,279 164,180 1,823,249 1916 286,780 860,663 13,960 114,173 101,475 1,377,051 1915 428,819 592,169 8,253 1,029,241 1914 219,188 153,896 373,084 1913 171,505 171,505 1912 124,267 124,267 1911 40,319 40,319 1910 1,184 1,184 a. A slightly greater production than shown was obtained as the tonnage from individual operations is not shown. b. Decrease due to strike conditions in 1920. c. Does not include tonnage of D., L., & W. d. D., L., & W. decrease in 1920 due to having less mining machines in operation. There are about 150 undercutters in use in the anthracite region, 80 mechanical loaders, and 10 longwall conveyors.

Jan 9, 1921

By Marius R. Campbell

VArIoUs classes of coals are recognized in this country at the present time. These classes depend largely upon physical characteristics rather than upon chemical composition, and consequently they cannot be accurately defined. The divisions into anthracite, semi-anthracite and semi-bituminons are fairly satisfactory; but the term bituminous embraces so large a variety of coal that it is of little value, and the term lignite is so loosely applied that it has little or no place in a scientific classification.

Jan 1, 1906

By W. C. Roberts-Austin

The subject with which the Council of the American Institute of Mining Engineers has entrusted me is one of much interest. It has been so admirably treated in America by Prof. Carl Barus* that I should have hesitated to deal with it had not the adoption of pyrometric methods in England recently occupied much attention, especially in relation to metallurgical industries and research. I shall endeavor to show what is the present state of our knowledge of practical pyrometry by briefly tracing the history of the efforts which have been made to measure high temperatures. This paper will, therefore, be limited to the consideration of those forms of appliance which have either marked distinct stages of advance, or have remained in use with more or less modification through a considerable range of time. The earliest pyrometers were essentially thermoscopes, and although their graduation presented great difficulties, their importance as affording a means for the measurement of high temperatures has been recognized for centuries. It would be difficult to illustrate this better than by a brief record of the testimony which has from time to time been offered by those who have had to apply the heat of furnaces in research or in industry, and it is mainly for the sake of the light incidentally thrown on the progress of both that the following historical notes are offered. In the eighth century, Geber, the chemist, wrote a treatise on furnaces, and showed that he was familiar with many and varied means of applying heat; but he points to the difficulties that are met with in conducting operations at high temperatures, which he attributed to inability to measure heat, his actual words being: " sed quoniam non est res ignis, quae mensuari possit." t

Jan 1, 1894