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By Henry Rawdon

ONE of the most vital problems in the manufacture of steel at present is the occurrence of the defects that have been popularly termed "snow flakes," "flakes," or "scabs." Particularly is this the problem of many manufacturers who during the past 2 yr. have undertaken large-scale production for the first time. A study of the microstructure of such defective material throws considerable light upon the nature of these defects and is essential before measures may be taken for the elimination of the defects. Flakes do not appear to be found in the plain carbon steels; they have been found, however, in abundance in some of the simple alloy steels that are being used in such vast quantities; viz., nickel steel of the approximate composition, 0.40 carbon and 3.5 per cent. nickel, and in the chrome-nickel type. The present article summarizes the characteristic features of defective steel of the flaky type as they have been found by laboratory study of numerous specimens, and it aims to show the conditions within the metal that are favorable to the occurrence of this type of defect without entering into the details of mill practice (size of ingot, design of molds, rate of cooling, distribution of cooling stresses, etc.), all of which conditions appear to play a role in the production of these defects.

Jan 2, 1919

By F. C. Kelley, L. L. Wyman

In order to clarify and amplify the existing data concerning the action of the cementing material in cemented tungsten carbide alloys, the authors have initiated this investigation of the entire range of cobalt-tungsten carbide alloys. Inasmuch as the ultimate objective is relative to what actually goes on during the sintering of cemented tungsten carbide materials, this work was necessarily restricted to heat treatments similar to those used in actual production of these materials. In the course of numerous experiments, the authors have noted several conditions that indicated that there was a solubility to be considered. Among these factors are the following: 1. Many of the alloys showed a much larger amount of binding constituent to be present than could possibly be accounted for by the cobalt content. 2. In many areas, grains of the carbide constituent are much larger than the particles of carbide originally added. In addition, these grains are of very regular contour. 2a. In samples of cemented tungsten carbide which had been fused in the atomic hydrogen torch in the presence of excess binder constituent, immense grains are formed, and their shapes are very regular. This is also true when the cemented tungsten carbide of 13 per cent. Co content is fused alone in the atomic hydrogen torch. Contrary to general expectation, chemical analysis of this material, after fusion in the atomic hydrogen torch, checks the analysis of unfused material. 3. In making the cemented tungsten carbide materials by the process of exerting the pressure at the time of heating a certain portion of the ' contents squeezed out of the mold. Chemical analysis has shown that this material contains approximately 12 to 20 per cent. of tungsten. The microstructure shows a cored dendritic structure interlaced with eutectic network, and some graphite, as shown in Fig. 1. 4. Thermal analysis of these materials has consistently indicated an arrest point close to 1350" C.

Jan 1, 1931

FRIENDS of the late Charles F. Rand presented in 1930 a sum of money from which the income is available to support various phases of the work of the Institute in which Mr. Rand was so deeply interested. At present the fund amounts to $10,400. The specific terms of the deed of gift are as follows: "The fund collected to establish a memorial to the late Charles F. Rand shall be placed in the custody of the Board of Directors of the American Institute of Mining and Metallurgical Engineers, to be set up as a trust to be known as the `Charles F. Rand Foundation,' the income of which shall each year be applied to a distinct purpose to be decided upon in that year by vote of the Board of Directors. This purpose shall be such as to promote the general welfare of the Institute and to constitute a permanent memorial of the usefulness of Mr. Rand, who for many years gave unstintingly of his time and talents in its service. "It shall be within the discretion of the Board of Directors to establish a medal to be known as the Charles F. Rand Memorial Medal to be awarded at such a time and under such rules as may be determined by the Board of Directors, for Distinguished Achievement in Mining Administration." The establishment of this medal was announced at the annual meeting in February, 1932, the term "mining" being defined in its broad sense to include metallurgy and petroleum. Robert Linton is chairman of the Charles F. Rand Foundation Award Committee.

Jan 1, 1944

By Kermit Allen

Historically, major natural gas transmission companies have been faced with the problem of meeting peak demands when the source of natural gas is located hundreds of miles away from the marketing area. Transcontinental Gas Pipe Line Corp.'s position was further complicated when offshore gas supply wells were shut-in during hurricane alerts. Transco's solution to this problem was the construction of salt storage wells adjacent to their pipeline near Eminence, Miss. Storage caverns were constructed using conventional solution mining methods. Two 13 3/8-in.-diam cased wells were completed and a 1,000,000-bbl cavern was leached at an interval of 5700 to 6700 ft at the base of each well. The two caverns have a usable storage volume of 2.0 billion cu f t and each well has a deliverability rate of 375 million standard cfd. The caverns are unique in that brine is not used for product displacement-all brine has been removed from the caverns. Natural gas is stored at a maximum pressure of 4000 psia. During withdrawal the cavern pressure drops to a minimum of 1225 Asia-the volume of gas between these two pressures becomes "usuable or top gas." The Eminence storage terminal is located on the Eminence salt dome about 30 miles north of Hattiesburg, Miss. Construction began in July 1968 and was completed in October 1970.

Jan 1, 1972

By William Plank

In practically all rock-excavation problems there is need for a careful study of the rock structure, its fault, cleavage or bedding planes, and even the texture of the rock itself. These studies should form the bases upon which an excavation method is selected and they should be carefully considered in predicting the amount and extent of the excavation. The need for such studies was forcibly illustrated in the problems involved in a cut made in 1929, along and underneath a 200-ft. high rock projection for a State-highway near the City of Easton, Pennsylvania. The rock mass was badly faulted and also contained a number of cleavage planes at approximately right angles to the fault planes. Much of this structure was visible and could have been studied and analyzed before' the work was begun. The State had rigid specifications as to finished grade and slope of cut, which apparently were made without reference to the geologic structure. The contractor complied with the specifications, under the close inspection of the State engineers. A tunnel blast was, placed in the base of the cliff, with the result that 65 per cent more rock was broken than was intended by the specifications. About four years after the blast, the writers of this paper studied the circumstances surrounding the operation, to determine the cause of this excess excavation.

Jan 1, 1935

By J. Norman Bulkley

As electrical power is used to a greater extent on the Rand than in any other mining center, it is thought that a short description of the methods used and results obtained may be of interest. In comparing Rand practice with that on other fields, several general factors should be borne in mind: First, the mines are all working on large tonnages of low-grade ore (average. $6.50). The annual crushing rate is about 27,000,000 tons. Second, the mines are all grouped udder the financial and engineering control of mining houses, so that the results of a group, rather than an individual mine, are open for study, and practice follows more uniform lines. Third, coal of fair quality (about 12,000 B.t.u.) can be obtained for $2 to $3 per ton., Good supplies of condensing water are, however, scarce, and have to be carefully stored. Power Supply Power is supplied by the Victoria Falls & Transvaal Power Co., Ltd., and its subsidiary, the Rand Mines Power Supply Co. Both companies, which are practically one from an engineering point of view, operate the following stations, all feeding into the same system.

Jan 2, 1916

By R. M. Hudson, P. E. Perry

Weight-gain data obtained by nitriding low-carbon sheet steel in an amrnonia CNH,) atmosphere indicated that the process obeyed a parabolic rate law. The calculated actization energy for nitriding in the range 964" to 1268°F agreed reasonably well with published data. At 1358"F, rate data indicated that the activation energy decreased. Weight-gain data obtained by uszng mixtures of NH3 -Nz at 1268°F containzng jrom 10 to 100 zol pct NH3 also obeyed a parabolic rate law. The rate of 'nitriding increased with an increase in the NH3 content of the gas Mixture. It is well-known that steel heated in gas mixtures containing ammonia (NH3) takes up much larger quantities of nitrogen than steel heated in nitrogen, both gases having a total pressure of 1 atm;' this phenomenon can presumably be attributed to the catalytic decomposition of NH3 on the steel surface to furnish nascent (monatomic) nitrogen. This process was studied bv Brunauer. Jefferson, Emmett, and Hend-ricks at furnace temperatures of 752" and 831°F2 using mixtures of NH3 in Hz. Englehardt and wagner3 reported that, at a furnace temperature of 914°F and under their experimental conditions, both nitriding and denitriding were controlled by the rate of gas-metal reactions at a steel surface rather than by the rate of diffusion of nitrogen in iron. The present study was undertaken to obtain information on the kinetics of nitriding low-carbon steel strip at higher temperatures so that practical rates for short-time strip-annealing treatments could be estimated. Variables studied included time: temperature, and NH, content in the annealing atmosphere. Mechanical and chemical characteristics of steel nitrided in this manner will not be considered in the present article. MATERIALS AND EXPERIMENTAL WORK The samples used were from a commercial low-carbon steel, 0.0244 cm thick, in the cold-reduced condition. The chemical composition of this steel is given in Table I. Panels were cut to 5.1 by 17.8 cm, degreased in toluene, and weighed just before treatment. Four specimens were nitrided under each of the experimental conditions. A study was made of the nitriding rate of steel in a 100 vol pct ammonia atmosphere, 740 mm pressure, at five specific temperatures within the range 964" to 1358°F. The nitriding rates of steel in ammonia-nitrogen gas mixtures containing 10, 18, 26, 50, and 100 vol pct ammonia, 740 mm total pressure, at 1268°F were also determined. All atmospheres used were dried by successively passing them through drying towers packed with soda lime and with Linde Molecular sieve Type 4A. Quoted gas compositions refer to those entering the furnace. Specimens were held in the constant-temperature zone of a vertical annealing tube furnace for times of 14, 3, 5, 10, or 15 min. Gas flow rates were maintained at 3.8 cu ft per hr, which was nineteen volume changes per hour for the system used. The rate of flow was selected to provide a high level of free NH3 for cracking on the steel surface where the ammonia gas is most effectively used as a nitriding agent. The vertical annealing tube furnace consisted of a Hevi-Duty tube furnace with a 2 1/2-in.-ID mullite ceramic high-temperature tube. The constant-temperature zone (controlled within 10°F) was about 10 in. long. After each specimen was degreased, a hole was punched in one end, for attaching the specimen by hook to a chain so that it could be lowered into or raised from the high-temperature portion of the tube by means of a power-driven winch. A stainless-steel access port with O-ring seals was connected by suitable glass-to-metal seals to the cool upper portion of the furnace tube. After the weighed specimen was placed in the access port, the furnace tube was evacuated to approximately 10"3 torr, and then the system was flushed thoroughly with the atmosphere under study. When the gas flow rate and constant-temperature zone of the furnace were established, the specimen was lowered into the constant-temperature zone. The atmosphere flowed from the top to the bottom of the vertical furnace tube and was then vented. For all these runs, during the first 3 min of the time the specimen was in the constant-temperature zone of the furnace the specimen was heating up to the tempera-

Jan 1, 1970

By P. D. Proctor, M. P. Nackowski

Quantification in recording geologic phenomena and application of well-known geologic principles to engineering works continued at an increasing rate during the year. Highway departments, water resources agencies, private firms and governmental agencies involved in tunnel excavations, dam site locations and construction, consultants and government experts in subsurface liquid-waste disposal, designers of underground storage facilities and city and regional planners all confirmed greater use of applied geology in their planning and implementation of plans. Applications of quantified geologic data to highway locations, slope control of cuts, raw material sources, water sources and water run- off showed a striking increase in number. Environmental geology and geologic hazards became part of the jargon of the geologic profession, and the American public began to realize more fully the significance of where they live, and on what and near what geologic phenomena which might effect their well-being. Tunnel work for water projects of almost dream-like magnitude kept geologic engineers busily engaged in predicting and testing local geologic conditions for construction projects. Disposal of industrial and radioactive liquid wastes continued as problems, but use of stratigraphic data, fluid flow rates and direction of flow helped solve some critical waste disposal problems. Unusual applications of seismic networks, remote sensing methods and X-ray techniques in geological engineering applications added other tools to this increasingly important profession.

Jan 2, 1968

David THOMAS 1871 R. W. RAYMOND 1872-1874 A. L. HOLLEY 1875 ABRAM S. HEWITT 1876 T. STERRY HURT 1877 ECKLEY B. COKE 1878-1879 WILLIAM P.SHINN 1880 WILLIAM METCALF 1881 RICHARD P. ROTHWELL 1882 ROBERT W. HUNT 1883 JAMES C. BAYLES 1884-1885 ROBERT H. RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B. POTTER 1888 RICHARD PEARCE 1889 ABRAM S. HEWITT 1890 JOHN BIRKINBINE 1891-1892

Jan 1, 1929

International Trade in Nonmetallic Minerals. BY J W FURNESS AND E W PEHRSON (Man &. Met, Sept, 432 2500 words) International trade in nonmetalic minerals (exclusive of fuels) is dominated largely by fertilizer raw materials such as phosphate rock, potash, nitrates, sulphur and pyrites and the miscellaneous group of minerals including asbestos, mica, graphite, fluorspar and china clay Cost of trans¬portation deters any substantial movement of the building materials which usually occur widely in nature and are thus available near consuming centers at relatively low cost This paper, which presents a summary for 1932 of the world production, consumption and principal trade relations of asbestos, china clay, fluorspar, graphite, gypsum, mica, phosphate rock and potash illustrated by world charts, is based on an original study of 15 nonmetallic minerals conducted by the U S Bureau of Mines Practical and Legal Aspects of Mme Financing See METAL MINING Economic Significance of High-grade Concentrates See MILLING AND CONCENTRATION

Jan 1, 1937

By James R. Holden, Frederick E. Wang

Through both single-crystal and powder X-ray diffraction methods, ten A6B23-type compounds have been confirmed to exist between lanthanides (A) (plus scandium and yttrium) and manganese (B); A = Y, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu. The formation of a compound of this type is shown to he extremely atomic size-sensitive; hence it can be classified as a "size-factorH compound. The "enveloping effect", a geometrical consideration observed in its crystal structure, is proposed as the reason for the A6B23-type compound being size-sensitive. The approximate ideal geometrical ratio of the radii R/r is 1.31 while experimentally A6B23-type compounds have a radius ratio lying within the range 1.2 to 1.4. FLORIO t al.' characterized the structure of Th6MnZ3 as fcc, space group Fm3m, with 116 atoms in the unit cell. Since then, a number of isotypic binary compounds, and recently Gd n,,' have been confirmed to exist. The fact that strontium and barium form A6Bz3-type compounds with magnesium strongly suggested the possible existence of Ba6Liz3. However, investigation3 showed the compound Ba6LiZ3 to be absent. Since both strontium and barium are group 11-a elements and are therefore "open metals",6 the nonexistence of Ba6LiZ3 can hardly be explained satisfactorily by valence-electron considerations. On the other hand, the consistent atomic-radius ratio, (R/r),* observed for the known A6Bz3-type compounds,3 strongly suggests that the formation of compounds of this type is atomic size-sensitive. Therefore, one is tempted to explain the nonexistence of Ba6LiZ3 entirely on the basis of the atomic-size difference between strontium and barium. However, this approach is not entirely without objection. Atoms are not rigid spheres and are known to vary in size within certain limits.7 Since the atomic-radius difference between strontium and barium (0.07 to 0.09A) is within these limits, it is reasonable to assume that the size difference would have a negligible effect on the formation of Ba6LiZ3. This view is further supported by the fact that the radius ratio, R/r, in other known "size-factor" compounds is observed to range widely—for example, from 1.08 to 1.45 for ABz-type compounds (C15, MgCuz type)' and from 1.37 to 1.58 for AB5-type compounds (D2d, CaZn5 type).g The present investigation was undertaken in order to find a more satisfactory explanation for the non-existence of Ba6LiZ3 and, consequently, a better understanding of the nature of the A6Bz3-type compound. The primary objectives are to confirm the previous conclusion3 that the A6B23-type compound is indeed a "size-factor" compound and subsequently to determine the atomic-radius ratio range in which the A6Bz3-type compound can exist. In order to achieve these objectives, stoichiometric A6Bz3 alloys, where manganese (B) was alloyed with various lanthanide elements (A), were selected for investigation. The atomic-radius ratios of lanthanide elements with manganese range from 1.26 for Lu/~n to 1.46 for Eu/Mn. This radius ratio range includes and exceeds the range of all previously reported A6Bz3-type compounds—1.32 for Th/Mn' through 1.38 for Sr/Li. Furthermore, the atomic-size difference between successive elements of the lanthanide series in order of atomic number) is of the order of 0.01A (europium and ytterbium are exceptions). The series of lanthanon-manganese alloy systems is ideally suited to a precise determination of the limits of allowable atomic-radius ratio for A6Bz3-type compound formation. EXPERIMENTAL PROCEDURE The lanthanide metals, in ingot form, supplied by Michigan Chemical Corp. (St. Louis, Mich.) and Nuclear Corp. of America (Burbank, Calif.), were guaranteed by the suppliers to be at least 99.9 wt pct pure (traces of silicon, calcium, and other minor constituents present on occasion, not to be more than 0.05 wt pct) as shown by spectrographic analysis. Manganese metal, in polycrystalline form, was redistilled from the commercial, chemically pure grade and was analyzed to be at least 99.95 wt pct pure. In all cases, the atom ratio between the two elements in each charge was A (rare-earth meta1):B (manganese) = 6:23 and a constant weight, 3 g, of

Jan 1, 1965

MINING METHODS W. J. COULTER, Chairman P. B. BUCKY, Vice-Chairman CLYDE E. WEED, Vice-Chairman ROBERT S. PALMER, Secretary Alluvial Mining CLINTON BERNARD O. B. PERRY NORMAN CLEAVELAND C. M. ROMANOWITZ R. B. EARLING J. B. STAPLER BENERE H. GRANTCHARLES THURMAN Open-Cut Mining Iron. A. D. CHISHOLM EARL E. RUNNER G. E. DIEHL G. E. LEVEQUE P. G. HARRISON SIMPSON RICHEY W. A. STERLING

Jan 1, 1943

By C. L. Berrien

MANY fires have occurred in the mines of Butte in recent years, and while all have been of a serious nature, simply because they were mine fires, six of them have been especially dangerous in respect to loss of life and property, and the expense of extinguishing or controlling them. It is not my intention to discuss the relative merits of methods used in fighting these different fires because the conditions under which they occurred varied in each case, and it was not always advisable to expend the large sum of money necessary to actually extinguish them if they could he bulk-headed off from the rest of the mine. It is needless to say that everything possible has been done to check all fires at the beginning, but without success in some cases; and it has then become necessary to bulkhead all connections to them, in which state several now exist. The mine fires of Butte, or fires in any mine, may be divided into two classes, namely: Those occurring in accessible workings, and those occurring in inaccessible workings; because these two conditions govern to the greatest extent the methods of fighting fires. Accessibility and in-accessibility in the case of mine fires concern not only new open workings and old closed workings, respectively, but also the condition of the ventilation in and about those places. When a fire is accessible at the start it should not be difficult to confine it to a small area and extinguish it in a relatively short time, but when it is impossible to actually reach a fire in old filled, abandoned workings, or there is no opening by which the gases may be conducted away from the fire zone, then the time consumed in changing those conditions permits the fire to increase to such an extent that it is a long, hard fight to overcome it.

Jan 6, 1915

By Bever M. B., Floe Carl F., Hung Liang

Data on the solubility of hydrogen in iron-silicon alloys are of practical interest, as hydrogen causes gas unsoundness and embrittlement in iron and steel and is also a factor in the metallurgy of cast iron. Zapffe and Simsl have recently demonstrated that in deoxidized iron and steel castings gassiness and bleeding are primarily functions of the hydrogen content of the liquid metal. These authors also suggested convincingly that ordinary melting and casting practice provides several sources of hydrogen for absorption by the metal. Norbury and Morgan2 and Boyles3 have shown that dissolved hydrogen affects the graphitization of cast iron. Schneble and Chipman4 included in a study of the effects of superheating on the properties of cast iron an investigation of the part played by hydrogen. Schwartz, Guiler and Barnett5 investigated the significance of hydrogen in the metallurgy of malleable cast iron. A complete interpretation of investigations of this kind calls for equilibrium values of the solubility of hydrogen in the liquid and solid phases. From the theoretical standpoint, the solubility of gases, especially hydrogen, may reveal some aspects of the nature of liquid metallic solutions. This was implied in the early work of Sieverts6 on the effect of alloying additions on the solubility of hydrogen in copper. Recent work by Bever and Floe7 has shown that in liquid copper-tin alloys the solubility of hydrogen changes abruptly at the composition of the intermetallic compound Cu3Sn. It is of considerable interest to determine whether liquid alloys of iron also have compositions at which the solubility of hydrogen exhibits a discontinuous or otherwise unique behavior. Among the various alloys of iron the iron-silicon system is important because of the presence of silicon in various structural alloy steels, transformer sheets, cast irons and special acid-resisting castings. The various grades of ferrosilicon, finally, cover almost the entire remainder of the composition range. Published information on the solubility of hydrogen in iron-silicon alloys is meager. The first values for pure liquid iron were reported in 1910-191 1 sieverts and Krumbhaar8 and by sieverts.9 They found that 100 grams of iron absorbs 28 c.c. of hydrogen at 1550°C and One atmosphere pressure, and 31 C.C. at 1650°C. In 1938 Sieverts, Zapf and Moritz10 published a value of 26.3 C.C. at 1550°C. Data on the solubility of hydrogen in liquid iron-silicon alloys and in liquid silicon are not available. Martin1' investigated

Jan 1, 1947

By Bever M. B., Floe Carl F., Hung Liang

Data on the solubility of hydrogen in iron-silicon alloys are of practical interest, as hydrogen causes gas unsoundness and embrittlement in iron and steel and is also a factor in the metallurgy of cast iron. Zapffe and Simsl have recently demonstrated that in deoxidized iron and steel castings gassiness and bleeding are primarily functions of the hydrogen content of the liquid metal. These authors also suggested convincingly that ordinary melting and casting practice provides several sources of hydrogen for absorption by the metal. Norbury and Morgan2 and Boyles3 have shown that dissolved hydrogen affects the graphitization of cast iron. Schneble and Chipman4 included in a study of the effects of superheating on the properties of cast iron an investigation of the part played by hydrogen. Schwartz, Guiler and Barnett5 investigated the significance of hydrogen in the metallurgy of malleable cast iron. A complete interpretation of investigations of this kind calls for equilibrium values of the solubility of hydrogen in the liquid and solid phases. From the theoretical standpoint, the solubility of gases, especially hydrogen, may reveal some aspects of the nature of liquid metallic solutions. This was implied in the early work of Sieverts6 on the effect of alloying additions on the solubility of hydrogen in copper. Recent work by Bever and Floe7 has shown that in liquid copper-tin alloys the solubility of hydrogen changes abruptly at the composition of the intermetallic compound Cu3Sn. It is of considerable interest to determine whether liquid alloys of iron also have compositions at which the solubility of hydrogen exhibits a discontinuous or otherwise unique behavior. Among the various alloys of iron the iron-silicon system is important because of the presence of silicon in various structural alloy steels, transformer sheets, cast irons and special acid-resisting castings. The various grades of ferrosilicon, finally, cover almost the entire remainder of the composition range. Published information on the solubility of hydrogen in iron-silicon alloys is meager. The first values for pure liquid iron were reported in 1910-191 1 sieverts and Krumbhaar8 and by sieverts.9 They found that 100 grams of iron absorbs 28 c.c. of hydrogen at 1550°C and One atmosphere pressure, and 31 C.C. at 1650°C. In 1938 Sieverts, Zapf and Moritz10 published a value of 26.3 C.C. at 1550°C. Data on the solubility of hydrogen in liquid iron-silicon alloys and in liquid silicon are not available. Martin1' investigated

Jan 1, 1947

By Carl F. Floe, Hung Liang, Michael B. Bever

DATA on the solubility of hydrogen in iron-silicon alloys are of practical interest, as hydrogen causes gas unsoundness and embrittlement in iron and steel and is also a factor in the metallurgy of cast iron. Zapffe and Sims1 have recently demonstrated that in deoxidized iron and steel castings gassiness and bleeding are primarily functions of the hydrogen content of the liquid metal. These authors also suggested convincingly that ordinary melting and casting practice provides several sources of hydrogen for absorption by the metal. Norbury and Morgan,2 and Boyles3 have shown that dissolved hydrogen affects the graphitization of cast iron. Schneble and Chipman4 included in a study of the effects of superheating on the properties of cast iron an investigation of the part played by hydrogen. Schwartz, Guiler and Barnett6 investigated the significance of hydrogen in the metallurgy of malleable cast iron. A complete interpretation of investigations of this kind calls for equilibrium values of the solubility of hydrogen in the liquid and solid phases. From the theoretical standpoint, the solubility of gases, especially hydrogen, may reveal some aspects of the nature of liquid metallic solutions. This was implied in the early work of Sieverts6 on the effect of alloying additions on the solubility of hydrogen in copper. Recent work by Bever and Floe7 has shown that in liquid copper-tin alloys the solubility of hydrogen changes abruptly at the composition of the intermetallic compound Cu3Sn. It is of considerable interest to determine whether liquid alloys of iron also have compositions at which the solubility of hydrogen exhibits a discontinuous or otherwise unique behavior. Among the various alloys of iron the iron-silicon system is important because of the presence of silicon in various structural alloy steels, transformer sheets, cast irons and special acid-resisting castings. The various grades of ferrosilicon, finally, cover almost the entire remainder of the composition range. Published information on the solubility of hydrogen in iron-silicon alloys is meager. The first values for pure liquid - iron were reported in 1910-1911 by Sieverts and Krumbhaar8 and by Sieverts.9 They found that 100 grams of iron absorbs 28 C.C. of hydrogen at 1550°C. and one atmosphere pressure, and 31 C.C. at 1650°C. In 1938 Sieverts, Zapf and Moritz10 published a value of 26.3 c.c. at 1550°C. Data on the solubility of hydrogen in liquid iron-silicon alloys and in liquid silicon

Jan 1, 1946

By J. R. Craig, T. N. Solberg, M. A. Linden

The central and southern Appalachian Mountains were the major sources of domestically produced gold throughout the first half of the 19th century and continue to yield gold today. Small amounts of gold were probably extracted by the Indians and the Spaniards but the first documented report of gold in the region was made by Thomas Jefferson who found, in the Rappahannock River of Virginia in 1782, a 1.8 kg (4 lb) lump of gold ore that yielded 26 g (0.85 oz). Gold was subsequently discovered in North Carolina between 1793 and 1799, in Virginia in 1806, in South Carolina in 1827, in Georgia in 1829, and in Alabama about 1830 (Becker, 1894-5; Pardee and Park, 1948). Production climbed to more than 933 kg/a (30,000 oz per year) between 1830 and 1852, but dropped sharply after the California gold rush in 1849 as experienced miners moved west in search of bigger and easier stakes. The Civil War briefly halted gold mining in the Appalachians, but production rose to an average of about 249 kg/a (8,000 oz per year) from 1865 until 1878 and to about 404 kg/a (13,000 oz per year) from 1881 until 1915 when it again fell to near nil (Pardee and Park, 1948). Minor resurgences occurred in the 1930s and 1940s. Although there has been no reported production in recent years, it is likely that "weekend panners" still remove hundreds of ounces from streams annually. The total reported production for the area through 1959 is more than 77 t (2.5 million oz). This paper reports some initial findings of a long-term project designed to investigate the mineralogy, chemistry, mode of occurrence, and petrology of gold occurrences in the Appalachians. The goal of the initial phase was to determine the compositional range of gold in the Appalachians as a step toward deciding if sufficient variations were present to allow the definition of "compositional signatures." The very few published data on gold fineness in the Appalachians are based on assays that commonly include gold and silver from several mineral species. Analyses in the present study were performed on individual grains of electrum using a spot size of 10 µm x 10 µm to 100 µm X 100 µm (394 X 394 micro in. to 3,940 X 3,940 micro in.), and thus reveal the true composition of the principal precious metal-bearing phase.

Jan 1, 1984

By McHenry Mosier

MeRcuRy is one of the strategic metals of which the supply has been raised from critical uncertainty to more than enough for essential demands. Work by the Bureau of Mines has contributed substantially to increased production of mercury in the United States and to consequent accumulation of Government stocks. Other contributing factors have been higher prices for mercury and Government loans to operators. The Bureau has undertaken 13 exploration projects, 10 of which have been completed. This work has comprised 28,376 ft. of several types of drilling and 23,798 lin. ft. of surface trenching, and has indicated commercial ore containing 34,800 flasks of mercury and marginal ore containing 26,200 flasks, a total of 61,000 flasks; equivalent, respectively, to domestic production for 8 months, 6 months, and 14 months. As Government stocks are now adequate, domestic production (currently at the rate of 50,000 flasks per year) is gradually being curtailed through Government control of labor and operating supplies. Introduction Mercury was one of the seven metals designated as strategic by the Army and Navy Munitions Board in 1939, when Congress appropriated funds for the investigation of domestic sources of supply of war minerals. The Bureau of Mines immediately started a limited search for strategic minerals, but the first mercury project was not begun until December 1940. The U. S. Geological Survey assisted in the search for cinnabar by contributing information on domestic mercury deposits, preparing maps, and making geological studies of exploration projects. The present high rate of production of mercury in the United States was encouraged by the increase in price to $196 per flask at New York (Fig. I) and Government loans to operators for mine development and plant construction. The Bureau of Mines has issued, for restricted distribution subject to wartime controls, 13 War Minerals Reports on individual mercury deposits (listed in appendix A). In March 1942 it also published a Progress Report of the Metallurgical Division, R. I. 3627, Cinnabar-reduction Plants of the Southwestern Arkansas Quicksilver District. Uses of Mercury Mercury and its compounds have more than 3000 uses. Its principal use is as a catalyst in the manufacture of gases for chemical warfare; the next largest is in pharmaceuticals. Mercury is essential also for: (I) certain electrical apparatus, (2) industrial control instruments at many war plants, (3) munitions, including blasting caps, (4) insecticides in agriculture, (5) antifouling paint for ship bottoms, (6) dental preparations, (7) general laboratory use, and (8) amalgamation of free-milling gold ores.

Jan 1, 1949

By McHenry Mosier

MeRcuRy is one of the strategic metals of which the supply has been raised from critical uncertainty to more than enough for essential demands. Work by the Bureau of Mines has contributed substantially to increased production of mercury in the United States and to consequent accumulation of Government stocks. Other contributing factors have been higher prices for mercury and Government loans to operators. The Bureau has undertaken 13 exploration projects, 10 of which have been completed. This work has comprised 28,376 ft. of several types of drilling and 23,798 lin. ft. of surface trenching, and has indicated commercial ore containing 34,800 flasks of mercury and marginal ore containing 26,200 flasks, a total of 61,000 flasks; equivalent, respectively, to domestic production for 8 months, 6 months, and 14 months. As Government stocks are now adequate, domestic production (currently at the rate of 50,000 flasks per year) is gradually being curtailed through Government control of labor and operating supplies. Introduction Mercury was one of the seven metals designated as strategic by the Army and Navy Munitions Board in 1939, when Congress appropriated funds for the investigation of domestic sources of supply of war minerals. The Bureau of Mines immediately started a limited search for strategic minerals, but the first mercury project was not begun until December 1940. The U. S. Geological Survey assisted in the search for cinnabar by contributing information on domestic mercury deposits, preparing maps, and making geological studies of exploration projects. The present high rate of production of mercury in the United States was encouraged by the increase in price to $196 per flask at New York (Fig. I) and Government loans to operators for mine development and plant construction. The Bureau of Mines has issued, for restricted distribution subject to wartime controls, 13 War Minerals Reports on individual mercury deposits (listed in appendix A). In March 1942 it also published a Progress Report of the Metallurgical Division, R. I. 3627, Cinnabar-reduction Plants of the Southwestern Arkansas Quicksilver District. Uses of Mercury Mercury and its compounds have more than 3000 uses. Its principal use is as a catalyst in the manufacture of gases for chemical warfare; the next largest is in pharmaceuticals. Mercury is essential also for: (I) certain electrical apparatus, (2) industrial control instruments at many war plants, (3) munitions, including blasting caps, (4) insecticides in agriculture, (5) antifouling paint for ship bottoms, (6) dental preparations, (7) general laboratory use, and (8) amalgamation of free-milling gold ores.

Jan 1, 1949

By William Kobbé

I. INTRODUCTION THE word recovery as used in this paper is applied in its broader sense and not limited to wells producing from horizons of unconsolidated sands. Certain problems connected with the winning of petroleum from such horizons present themselves while drilling is in progress and should be considered before drilling is commenced wherever unconsolidated sands are expected. Maximum recovery depends not alone upon efficient pumping methods but also upon the selection of a proper drilling system and the completion of a well especially adapted to the extraction of these oil-bearing sands. II. DRILLING DETERMINING FACTORS IN SELECTION OF METHOD The selection of a drilling method for the development of a region in which the oil reservoir consists of unconsolidated sands is based on the following considerations: (1) Character of the formations overlying the reservoir; (2) thickness of the oil-bearing stratum or strata; (3) thickness and character of water or gas sands; (4) gas pressure to be encountered or expected; (5) total depth of well.

Jan 12, 1916