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By F. D. DeVaney

IT is of great interest that the various organizations engaged in the search for a cheap and efficient agglomeration process for fine magnetite concentrates-essential if the taconites are to be utilized-have ended up with processes that are basically different. This paper describes the development and the present status of the shaft-type furnace as now utilized by the Erie Mining Co., which is managed by Pickands Mather & Co. The shaft furnace has always had an appeal to metallurgists because of the simplicity of the design and the possible low fuel consumption. Work done on pelletizing at the University of Minnesota Mines Experiment Station by E. W. Davis and his associates determined that it was possible to roll up fine magnetite concentrates in a balling drum, and that, if such balls were fired at a sufficiently high temperature, a hard, indurated pellet, well adapted for use in a blast furnace, could be made. Early furnaces had no heat recuperation and the heat consumption was in the order of 2 million BTU's per long ton.

Jan 3, 1958

STEPHEN TABER, Columbia, S. C. (communication to the Secretary?). -The fibrous salt crystals described by Dr. Branner are interesting, and I am glad that he has put this additional evidence on record. It confirms the results that I obtained in growing fibrous crystals in the laboratory. Much similar evidence of value to science in interpreting the laws of nature has doubtless been lost through failure to appreciate little things. Mr. Dresser points out that the boundary between chrysotile veins and massive serpentine is finely irregular 'when examined under the microscope. This fact I have observed in studying chrysotile veins and also, mode recently, in studying veins of fibrous calcite and fibrous gypsum. For the latter veins the statement holds true when the walls are of shale as well as when they are of the same material as the veins, but in no instance have I observed any evidence of replacement. The description of the vein walls given in my paper (pp. 1984 to 1985) was megascopic, not microscopic. The fact that chrysotile veins have sharply defined boundaries and are easily separated from the wall rock is evidenced by the small amount of waste adhering to the "crude asbestos" which has been shipped in such large quantities from some of the Canadian mines. Mr. Dresser has good ground for his statement that there seems to be no obvious reason why the term "mass fiber" should be restricted to anthophyllite. I have never examined the serpentine at the East Broughton mines; but in studying other serpentines under the microscope I have noted that much of the so-called "massive serpentine" is really finely fibrous (see pp. 1974 to 1975). The texture of such rock is, however, altogether different from that of mass-fiber anthophyllite, and I believe that the fibers have developed in a different way (see pp. 1981 and .1998). Mr. Graham raises certain objections on the ground that the laboratory production of fibrous crystals was limited to substances which go into solution with decrease in volume. Since my paper was written, however, I have succeeded in obtaining fibrous crystals of ammonium nitrate, a salt that dissolves with expansion in volume.

Jan 5, 1917

By H. C. Stumpf, L. A. Willey, V. L. Fink

Very few studies of the aluminum-sodium system have been reported. Heycock and Neville1 were unable to detect any solubility of sodium in liquid aluminum. Mathewson2 prepared an equilibrium diagram consisting of two horizontal lines at the melting points of the two metals. He was unable to detect solubility at either end of the system. Scheuer3 first developed a method for the chemical determination of sodium in aluminum and then studied the solubility of sodium in liquid aluminum. His method involved heating aluminum with excess sodium under hydrogen until the two liquids were at equilibrium, chilling the melt, and analyzing the aluminum-rich layer. He reported the solubility to be 0.10 pct sodium at 700°C, 0.115 pct at 750°C, and 0.128 pct at 800°C. This paper on the aluminum-sodium system is the twenty-first in a series from the Aluminum Research Laboratories describing equilibrium relations in aluminum alloy systems. Materials The alloys for this investigation were prepared from electrolytically refined aluminum (99.99 pct) and sodium of reagent quality conforming to specifications of the American Chemical Society. Chemical analysis of the aluminum showed the fol- lowing impurities: 0.002 pct Si, 0.002 pct Fe, 0.002 pct Cu, <0.001 pct Mn, 0.002 pct Mg and 0.001 pct Na. The sodium content of all alloys was determined by either chemical or spectro-graphic standard procedures5 No. IIA and No. SI I respectively. Determination of Miscibilitv The boundary of the miscibility gap was determined by a modification of the method of Scheuer3 and of that used by Henry and Cordiano. As finally developed the method was as follows: A fused alumina crucible 25 mm id with 75 mm depth and 1.5 mm wall thickness was placed on the bottom of a container made from a 4-in. length of 1 1/2-in. iron pipe and pipe caps. ?&apos;he space around the sides of the crucible was filled with 40 mesh crystalline alun-dum. A charge of 60 g of aluminum and 10 to 15 g of sodium was placed in the crucible, the sodium first being trimmed and rinsed with iso-pentane to remove kerosene. The container was tightly capped, filled with argon (99.6 pct pure), and heated to the desired temperature (between 670 and 800°C). A positive pressure of argon (about 8 mm of mercury) was maintained through a small pipe to the upper cap. After soaking for from 2 to 5 hr, the container was quenched by directing a stream of water onto the base, so that solidification of the aluminum-rich layer was rapid and essentially unidirectional. Analyses were made on drillings taken from the bottom of the ingots after machining off the surface layers. Pre-

Jan 1, 1949

By Gill Montgomery

The strong upward curve of fluorspar consumption continued through 1968, with domestic producers unable to furnish more than 30% of U.S. requirements. Stocks of all grades were quite short at all points during most of 1968. This resulted in price increases as both domestic and foreign producers sought to cover spiralling labor costs. Further increases are probable for 1969. All Illinois mines were closed by strikes in January and February. The strong trend in metallurgical imports reflects the increased use of fluorspar in steelmaking, as new oxygen process steel plants come into production. The growth of use of all fluorocarbon chemicals continues to require additional acid grade fluorspar, with military uses a major factor. Several new aluminum smelting facilities coming into production are adding to the aluminum fluoride needs, bringing further pressure upon the world supply of acid grade fluorspar. The world-wide consumption pressure on all grades of fluorspar is pushing prices up, and no end to the tight supply is in sight, even assuming that all the new projects cited here are finished on schedule.

Jan 3, 1969

By Bradley Stoughton, M. Miyake

The importance of magnesium alloys as engineering materials has increased rapidly in the past few years. The most important properties of magnesium alloys are their lightness and strength, which result in their extensive use in aircraft and automobile construction. Recent progress in the metallurgy of magneaium seems to offer hope of the production of the pure metal at a reasonable cost. The use of magnesium would doubtless increase greatly if it could be produced at a cost comparable with that of aluminum. A preliminary survey of the magnesium-base alloys shows that the most promising from a practical standpoint are magnesium-aluminum and magnesium-zinc as binary alloys, and magnesium-zinc-aluminum as ternary alloys. The research reported in this paper is a preliminary study of binary magnesium-aluminum and magnesium-zinc alloys, as an introduction to a series of further investigations. Magnesium-aluminum System The magnesium-aluminum system was first studied by Boudouard,1 who merely determined the liquidus. An accepted constitutional diagram was given by Grube,2 who found a compound A13Mg4 (melting point = 462.7" C.) and two eutectics at 35 per cent. magnesium (451.6° C.) and at 68 per cent. magnesium (440" C.) Between the first eutectic and the compound a solid solution exists. This diagram was checked or supplemented by Pécheux,3 Broniewski,4 Eger,5 Schirmeister,6 Voge17

Jan 1, 1926

By Julianne H. Glarmaty, Peter J. Conroy

INTRODUCTION In 1970 the percentage of underground coal extraction by longwall mining methods in the U.S. was 2.1 percent. This figure rose to 4.4 percent in 1976 and is expected to rise to 12 percent by the year 1985. This figure represents 46.0 million tons (51.0 million st) of annual production (Kuti, 1978). In addition, OSM regulations are placing emphasis on subsidence prediction. Section 784.20 of the Office of Surface Mining regulations for underground mining permit applications requires the sutauission of a subsidence control plan which may include monitoring. Because of its nature, longwall mining does not have flexibility in leaving pillars under structures as does room and pillar. Mining in some areas, particularly in the Eastern Coal Field, is approaching more developed areas; therefore, a greater number of structures are expected to be undermined in the near future. Subsidence engineering is becoming an important aspect of mine planning, and should be directed at predicting potential structural damage. The question operators are increasingly faced with is "what will be the subsidence effects for a specific structure at a specific location in respect to a longwall panel?" The most significant variable in assessing the subsidence effect on structures is not vertical subsidence. The variables of strain and tilt are responsible for more structural damage than is the vertical movement. Table I presents threshold values of strain for various structures (Geddes 6 Cooper, 1962). Based on National Coal Board experience, horizontal strain is approximately inversely proportional to the radius of curvature of a circular portion of a subsidence profile; therefore, the radius may be useful in estimating the magnitude of strain caused by subsidence (Hoebs, 1982). The radius of curvature can be determined by the following equation:

Jan 1, 1982

By Takahide Wakamatsu, Shigeru Mukai

Fundamental investigations were made on the treatment of slime and the chrysocolla flotation, both of which are urgent problems to be solved in copper oxide mineral flotation. Unfavourable effects of slime on flotation are caused by the slime adsorption at the air/liquid Interface as well as the slime coating on the mineral surface. The adsorption of slime at the air/liquid interface was measured by using various kinds of slime particles. As a consequence, goethite, bentonite and talc tended to adsorb markedly at the interface. As a desliming method, slime flotation with a polymer flocculant such as polyethylene-oxide prior to the ordinary copper oxide flotation was found to be effective. The use of both a copper-avid organic reagent and an alkyl xanthate was examined for a selective collection of chrysocolla through xanthate adsorption tests, chrysocolla float- abllity tests and flotation tests for synthetic and natural ore. The copper-avid reagents used were salicylaldoxime, 8- hydroxyquinollne and benzoin-a-oxime. As a result, the ad- sorption of higher xanthate such as amyl xanthate on chrysocolla as well as the chrysocolla-to-air bubble attachment was increased by the presence of a copper-avid reagent under suitable reagent addition and pH of pulp. Flotation tests for synthetic and natural ores confirmed that chrysocolla could be floated sufficiently and selectively with a copper- avid reagent like 8-hydroxyquinoline or salicylaldoxime with its subsequent collection by amyl xanthate.

Jan 1, 1976

By D. W. Frommer, M. M. Fine

Mineral dressing research showed that iron concentrates of commercial quality could be produced from the Pea Ridge deposit near Sullivan, Mo. Magnetic separation and flotation, on a laboratory scale, yielded concentrates ranging from 60.0 to 71.4 pet Fe at recoveries of 89.9 to 97.6 pct. Early in 1957 St. Joseph Lead Co. announced discovery of three new centers of iron ore deposition in east central Missouri.&apos; The discovery resulted from exploratory drilling in the vicinity of a magnetic anomaly or high. A deep hole, drilled into the Pre-Cambrian porphyry to determine the cause of anomaly, penetrated a magnetite-rich deposit.&apos; The magnetic surveys that revealed the anomalies were begun by the Missouri Geological Survey in 1929 and were continued into the 1930&apos;s.3 At that time an area in Crawford County known as the Bourbon magnetic high was located. A second anomaly, similar in size and intensity, was discovered about six miles to the northeast in Franklin County in the vicinity of Sullivan. This area was not studied in detail until the early 1940&apos;s. To determine the cause of the anomalies, the USBM drilled four holes at the Bourbon site in 1943-1944.4 The most productive hole penetrated four mineralized zones having a total thickness of 127.5 ft. These zones contained magnetite in rhyo-lite porphyry at depths between 1600 and 2000 ft. Additional iron ore below 2000 ft was considered a possibility at the time. Some years later, the USGS, Missouri Geological Survey, St. Joseph Lead Co., and others cooperated in sponsoring an aeromagnetic survey of the Bourbon-Sullivan area which resulted in discovery of a third high, about eight miles distant at Pea Ridge. This deposit, with an estimated reserve of 50 to 100 million tons of iron ore, is considered the main find, although other orebodies in the same general area are of definite interest.&apos; When this discovery was announced, St. Joseph Lead also revealed plans to exploit the deposit jointly with Bethlehem Steel Co. A new corporation, Meramec Mining Co., was established, and 1962 was set as the target date for completing physical plant.2 Annual production goals of 2 million tons of beneficiated and pelletized iron ore were proposed. Preparation of the site for shaft sinking was begun in June 1957. Orebody and Character of Samples: Drilling to date has established the Pea Ridge orebody as a crescent-shaped pipe about 300 ft wide. Some drillholes were bottomed at 2800 ft in very good iron ore.6 he orebody is predominantly magnetite, although hematite and a mixture of hematite and magnetite occur in the upper areas and peripheral walls. Drillhole cores representing ore from different areas and depths of mineralization were grouped into composites for testing. These composites consisted of: 1) medium grade mixed hematite and magnetite, 2) high grade mixed hematite and magnetite, and 3) high grade magnetite. The medium grade ore came from three holes with depths of i350 to 1900 ft. The high grade mixed hematite and magnetite cores came from the 1790 to 2812-ft interval of one hole. Partial chemical analyses of the three samples, given in Table 1, reveal that all are excessively high in phosphorus and sulfur, and sample 1 is

Jan 1, 1960

By T. O. Olsen, R. Henriksen

Aggregated models of a bank of flotation cells have frequently been used, assuming that a single-cell model can be used for control and estimation purposes. In this paper we investigate the feasibility of this approach, and show that single-cell aggregated models may very well be used in order to estimate the aggregated net flotation rate constants of the bank. These estimates would usually be very crucial in order to control the plant.

Jan 1, 1981

By Robert C. Bates

Is the value of rock sealant on radon control destroyed by changes in barometric pressure? While an article by Dr. Gerald Schroeder in the June 1977 issue of MINING ENGINEERING suggests this, it should be noted this is not necessarily true as the ensuing discussion reveals. Before analyzing the data leading to Dr. Schroeder&apos;s conclusions, some comments on their source are needed. The figures were collected during a 1973 US Bureau of Mines test of radon barrier coatings in the Dakota uranium mine near Grants, N.M. Results of that test were reported by Franklin, et al 3,4 in 1975. The mine is essentially dry and ore occurrence is within a lightly cemented, porous medium-to coarse-grained sandstone of high permeability and radon emanation rate.

Jan 12, 1977

By W. W. Stephen, J. P. Walsted, W. J. Kroll

FOR the production of carbides, various furnace types are available, especially those using arc, resistance, and high-frequency heating. Selection of a specific means of heating depends primarily on the material to be treated and the physical properties of the carbide produced. In the present case, zirconium carbide had to be prepared on an industrial scale as a raw material for the production of anhydrous zirconium chloride. Considering that a rather expensive pure oxide was to be used, the arc-furnace treatment recommended for zircon sands in a previous publication&apos; was ruled out because of the considerable volatilization and dust losses caused by the blast of the arc. For this reason, either high-frequency or resistance heating seemed to offer more promise. Since there was not enough capacity of the former available, resistance heating was chosen. It was first thought that the Acheson silicon carbide furnace would be suitable for the present purpose, but the voltage in such a furnace, in which the current passes through the batch, varies from 220 to 75 v from the start to the end of a run. This variation is so great that a special tap transformer would have been required. Trouble was also expected by local melting of the carbide. Pure zirconium carbide melts at about 3527°C, but the melting point is brought down to 2427°C, according to Agte,2 when an excess of 6 pct C is present in the carbide. This we found confirmed by experiments in a high-frequency furnace. Excess carbon is needed in the batch to obtain a complete reduction. Fusion of the charge would cause great difficulties in an Acheson-type furnace because of the good electrical conductivity of the carbide as compared with that of the loose batch. Also, fused carbide is much more difficult to chlorinate than the spongy product that can be made in the radiation furnace described below. It was apparent that, to obtain a good-qual-ity zirconium carbide, the heat input would have to be well-controlled. The hairpin-resistor principle seemed to offer possibilities in this regard, and a furnace of this type was therefore developed. The advantages of the hairpin-resistor radiation principle have been discussed in previous publications, and a split-tube graphite-resistor furnace," now increasingly used in various laboratories, as well as a centrifugal quartz melting furnace4 of this type, has demonstrated the usefulness of this heating method. The hairpin-heater element has the following definite advantages over a straight resistor of the type used, for instance, by Georges:5 Its resistance is four times greater; it can expand freely; it is sturdier because of the larger diameter, and it has a larger radiation surface; there are no hot contacts that might wear out or overheat; only one clamp is used which permits assembling all electrical leads at one side of the furnace, making the other sides easily accessible to the operator. The shorter element and its larger diameter permit greater concentration of heat. The furnace developed is shown in fig. 1. The box (I), made of 2 1/2-in. graphite plates, has inside dimensions of 23x17x16 in. It contains the briquet-ted batch (2). The box is embedded in lampblack (3) up to the cover plate. The cover plate contains an opening for the gas escape (4) and for the observation hole (5), which permits measuring the temperature with an optical pyrometer. The cover plate is embedded in charcoal (6). The lampblack is contained in the insulating brick lining (7), held in the 1/4-in. sheet steel box (8). The graphite box is set on two rows of triangular graphite bars (9). The hairpin-heater element (10), the dimensions of which are given below the main drawing, extends horizontally in the graphite chamber and radiates freely on the batch. A graphite tube (11) keeps the lampblack from falling into the slot. The split electrode, which in reality is turned 90" against the drawing, is so arranged that the slot is vertical. The water-cooled packing gland (12) is insulated by an airgap from the heater element. A thin pipe (13)

Jan 1, 1951

By J. W. Spretnak, G. Sachs

The: iron-rich iron-nickel alloys have attracted considerable academic interest in recent years. The carbon-free alloys are of minor practical importance, but they are the base of many alloys with various outstanding properties. The iron-nickel alloys, therefore, have been investigated extensively regarding both their structures and their properties. The researches on these alloys up to 1938 have been collected and critically reviewed by J. S. Marsh,l and will be discussed in some detail in the sections of this paper dealing with specific subjects. These numerous investigations have not succeeded in establishing the equilibrium conditions in this system. Alloys containing more than a certain amount of nickel (8 to 10 per cent Ni) undergo the allotropic transformation extremely sluggishly, both on heating and cooling, showing a large hysteresis," which is not dependent upon the rate of cooling and persists even with very slow rates of cooling.3 Honda4 and Merica4 have therefore resigned themselves to proposing a diagram (Fig. I) for practical use, illustrating the structural relations under commercial conditions instead of attempting to establish the true equilibrium diagram. Marsh is less pessimistic and suggests an equilibrium diagram (Fig. 2) which conforms approximately to the facts known about this system. Recent X-ray investigations by Owen-Sully5 and Bradley-Gold-schmidt6 on powdered alloys indicate that the previous work on the iron-nickel system yielded very incomplete results. These investigators agree (Figs. 3 and ,+) that alloys in the powdered form containing more than 8 per cent and up to about 35 per cent Ni decompose into a stable heterogeneous mix-

Jan 1, 1941

By G. Sachs, J. W. Spretnak

The: iron-rich iron-nickel alloys have attracted considerable academic interest in recent years. The carbon-free alloys are of minor practical importance, but they are the base of many alloys with various outstanding properties. The iron-nickel alloys, therefore, have been investigated extensively regarding both their structures and their properties. The researches on these alloys up to 1938 have been collected and critically reviewed by J. S. Marsh,l and will be discussed in some detail in the sections of this paper dealing with specific subjects. These numerous investigations have not succeeded in establishing the equilibrium conditions in this system. Alloys containing more than a certain amount of nickel (8 to 10 per cent Ni) undergo the allotropic transformation extremely sluggishly, both on heating and cooling, showing a large hysteresis," which is not dependent upon the rate of cooling and persists even with very slow rates of cooling.3 Honda4 and Merica4 have therefore resigned themselves to proposing a diagram (Fig. I) for practical use, illustrating the structural relations under commercial conditions instead of attempting to establish the true equilibrium diagram. Marsh is less pessimistic and suggests an equilibrium diagram (Fig. 2) which conforms approximately to the facts known about this system. Recent X-ray investigations by Owen-Sully5 and Bradley-Gold-schmidt6 on powdered alloys indicate that the previous work on the iron-nickel system yielded very incomplete results. These investigators agree (Figs. 3 and ,+) that alloys in the powdered form containing more than 8 per cent and up to about 35 per cent Ni decompose into a stable heterogeneous mix-

Jan 1, 1941

By D. S. Flett, D. W. West

The solvent extraction of chromium 111 has been studied for the system Cr 111, H,SO., H,O/RNH/RNH., xylene, where the primary amine used was Primene JMT. Rate studies have shown that extremely long equilibrium times are required, ranging from 1 hr at 80°C to 20 days at room temperature. Heating the solution prior to extraction increases the rate of extraction. The variation in the amount of Cr 111 extracted is an inverse function of the acidity of the aqueous phase. Thus, the slow rates of extraction appear to be connected with the hydrolysis of the Cr I11 species. Extraction isotherms for the extraction of Cr 111 have been obtained for two sets of experimental conditions, namely at 60°C and for a heat-treated solution cooled to room temperature. The separation of Fe 111 from Cr 111 and Cr 111 from Cu 11 in sulfate solution by extraction with Primene JMT has been studied and shown to be feasible. A survey of the literature relating to the solvent extraction of chromium showed that, although many systems exist for extraction of Cr VI, only a very few reagents have been found to extract Cr 111. The extraction of Cr III by di-(2-ethyl hexyl) phosphoric acid has been reported by Kimura.&apos; A straight-line dependence of slope —2 was observed between log D,, and the log mineral acid concentration at constant extractant concentration. Since the slope of this plot reflects the charge on the ion extracted, it must be concluded that a hydrolyzed species of Cr III is being extracted. Carboxylic acids generally do not form extractable complexes with Cr III but di-isopropyl salicylic acie does extract Cr 111. Simple acid backwashing of the organic phase, however, failed to remove the chromium. Similar difficulty in backwashing was found by Hellwege and Schweitzer8 in the extraction of Cr I11 with acetyl-acetone in chloroform. The extraction of Cr 111 from chloride solutions by alkyl amines has been reported4-&apos; but the maximum amount of extraction achieved in these studies did not exceed 10%: From sulfate solutions, however, Ishimori" has shown that appreciable amounts of Cr I11 were extracted by amines. The amines used were tri-iso-octyl amine, Amberlite LA-1 (a secondary amine, Rohm & Haas) and Primene JMT (primary amine, Rohm & Haas). The efficiency of extraction with regard to amine type was primary>secondary> tertiary. Appreciable extraction of Cr I11 was recorded for Primene JMT as the aqueous phase acidity tended to zero. The major difficulty with Cr I11 in solvent extraction systems stems from the nonlabile nature of the ion in complex formation. This accounts for the slow rate of extraction generally experienced and the difficulty encountered in backwashing the Cr I11 from the organic phase in the case of liquid cation exchangers. Consequently, the possibility of extraction of Cr I11 as a complex anion is attractive since the backwashing problems should be minimized in this way. From published data, it appeared that the extraction of chromium from sulfate solutions of low acidity by primary amines afforded the best chance of success for a useful solvent extraction system for Cr iii This paper presents the results of a study of the extraction of Cr I11 from sulfate solution by Primene JMT and examines the application of such an extraction procedure for the recovery of chromium from liquors containing iron and copper. Experimental Chromium solutions were prepared from chrome alum in sulfuric acid and sodium sulfate so as to maintain a constant concentration of sulfate ion of 1.5 molar. Solutions of Primene JMT were prepared in xylene and the amine equilibrated with sulfuric acid/sodium sul-fate solutions, of the same acidity as the chromium solution, until there was no change in acidity between the initial and final aqueous phases. The solutions of Primene JMT conditioned in this way were then used for the equilibration experiments. Equilibrations at 25°C were carried out in stoppered conical flasks shaken in a thermostat; equilibrations at all other temperatures were carried out in stirred flasks in a thermostat. After equilibration, the phases were separated and analyzed for chromium. In the tests on the rate of extraction, small samples of equal volume of both phases were withdrawn from time to time and the chromium distribution determined. The chromium analyses were carried out either coloi-imetrically using diphenyl carbazide, or volu-metrically using addition of excess standard ferrous ammonium sulfate and back titration of the excess iron with potassium dichromate. The oxidation of Cr 111 to Cr VI in the case of the raffinate solution was effected by boiling with potassium persulfate in the presence of silver nitrate and, for the backwash solution, by boiling with sodium hydroxide and hydrogen peroxide. Results Preliminary experiments indicated that extraction results were effected by the age of the chromium solution, higher distribution coefficients being obtained with solutions which had been allowed to stand for some time. Consequently a stock solution of chrome alum, 10 m moles per 1 Cr I11 in 1.4 M Na,SO,/O.l M &SO,,

Jan 1, 1971

By David B. Reger

The discovery of prolific oil wells in old territory hitherto regarded as doubtful, if not worthless, and the rapid extension of a gas pool opened late in 1938 were the most interesting petroleum features in West Virginia during 1939. Oil activity in general was slow because of crude prices that were still fairly low at the end of the year, although substantially increased above those in January. Fewer oil wells were completed, but the average results were better than in 1938. Fewer gas wells, also, were completed, with greatly lessened average initial production. Many old oil and gas wells were abandoned, so that the total number of active wells has not changed appreciably. The account of operations, as gathered from trade journals and other sources, shows that 561 new wells were drilled, resulting in 101 new oil wells with 2261 bbl. of daily initial production; 366 new gas wells with 602,400,000 cu. ft. of daily open flow; and 94 dry holes. Besides these new wells, 61 old wells were drilled to deeper sands, with 12 bbl. and 13,328,000 cn. ft. of added production. On the new wells the oil average was 22.38 bbl. per well per day; and the gas average was 1,645,900 cu. ft. per well per day; the ratio of dry holes to completions was 16.76 per cent. From an exploratory standpoint one partly discredited oil area was revived by good new production, and another small oil pool may have been opened. Some of the results in gas exploration will require more drilling for true appraisal. It is certain, though, that one very considerable gas field in the sands of Mississippian age has been proved; and there is a probability of six new pools in the Middle Devonian shale. In the Oriskany sand (L. Dev.) the Elk-Poca pool has been extended considerably farther northwest into Jackson County; and farther north in Jackson County two widely separated wells, which may be pool openers, have been successfully completed. On the other hand, several important wildcats in various counties have been dry. Stratigraphically lower, some additional wells have been completed in the Newburg sand (Sil.) and one small producer has been completed in the Clinton sand (Sil.), the importance of which can scarcely be overestimated, because no Clinton production has previously been found in the state, although at least seven wells have been drilled through the sand.

Jan 1, 1940

By David B. Reger

The discovery of prolific oil wells in old territory hitherto regarded as doubtful, if not worthless, and the rapid extension of a gas pool opened late in 1938 were the most interesting petroleum features in West Virginia during 1939. Oil activity in general was slow because of crude prices that were still fairly low at the end of the year, although substantially increased above those in January. Fewer oil wells were completed, but the average results were better than in 1938. Fewer gas wells, also, were completed, with greatly lessened average initial production. Many old oil and gas wells were abandoned, so that the total number of active wells has not changed appreciably. The account of operations, as gathered from trade journals and other sources, shows that 561 new wells were drilled, resulting in 101 new oil wells with 2261 bbl. of daily initial production; 366 new gas wells with 602,400,000 cu. ft. of daily open flow; and 94 dry holes. Besides these new wells, 61 old wells were drilled to deeper sands, with 12 bbl. and 13,328,000 cn. ft. of added production. On the new wells the oil average was 22.38 bbl. per well per day; and the gas average was 1,645,900 cu. ft. per well per day; the ratio of dry holes to completions was 16.76 per cent. From an exploratory standpoint one partly discredited oil area was revived by good new production, and another small oil pool may have been opened. Some of the results in gas exploration will require more drilling for true appraisal. It is certain, though, that one very considerable gas field in the sands of Mississippian age has been proved; and there is a probability of six new pools in the Middle Devonian shale. In the Oriskany sand (L. Dev.) the Elk-Poca pool has been extended considerably farther northwest into Jackson County; and farther north in Jackson County two widely separated wells, which may be pool openers, have been successfully completed. On the other hand, several important wildcats in various counties have been dry. Stratigraphically lower, some additional wells have been completed in the Newburg sand (Sil.) and one small producer has been completed in the Clinton sand (Sil.), the importance of which can scarcely be overestimated, because no Clinton production has previously been found in the state, although at least seven wells have been drilled through the sand.

Jan 1, 1940

By D. F. Gibbons

THIS investigation was undertaken in order to gain further information on the mechanism of plastic deformation of iron at temperatures between room temperature and 77.2°K, and also to contribute to our understanding of the low temperature brittleness phenomenon that occurs in both the tensile and impact tests. It was decided to study as pure an iron as possible and to use the tensile test in order to simplify the problem as much as possible. Two series of iron were used throughout the investigation: iron A, obtained from the National Research Corp. and supplied as gas-free, high purity iron; and iron B, obtained from Fast&apos; and produced by melting iron under purified hydrogen. Typical analyses of samples of both irons, after fabrication, are given in Table I. The main difference in composition of these irons is in their nickel and oxygen contents. Nickel has a very large solid solubility in iron. However, oxygen has an extremely small solid solubility. An attempt was made to reduce the oxygen content still further by remelting under purified hydrogen. This was successful in reducing the oxygen content to -0.0006 pct. However, no results on tests of this iron are included, since difficulty was encountered in fabricating the ingot. Wire specimens 1 mm in diameter were used for the investigation. The wires were produced from the ingots, as supplied, by cold rolling and swaging, with intermediate vacuum anneals at 700°C. Care was taken to reduce preferred orientation in the wires to a minimum by keeping the percentage of reduction in area between anneals of 30 to 40 pct. X-ray transmission photographs showed no indication of preferred orientation. The final grain size of iron A was 20 to 24 grains per linear mm and of iron B, 16 to 18 grains per linear mm. All specimens were tested in the decarburized and denitrided condition unless otherwise stated. The procedure was to pass hydrogen, saturated with water vapor at 26oC, over the specimens at 730°C for 2 hr. The specimens were quenched in iced water and then annealed in a vacuum of - 5x10-6 mm Hg for one day at 560°C to remove hydrogen. Higher temperatures were used for the vacuum anneal but this temperature was found to be quite satisfactory in removing hydrogen. The specimens were slow-cooled after the vacuum anneal. Where it is stated that the specimens were carburized, the specimens were given an identical decarburizing treatment and then carburized by passing hydrogen, saturated with pure n-heptane vapor at 0°C, over the specimens at 730°C. The specimens were then homogenized at 730°C for 2 hr in dry hydrogen. After the carburizing treatment the specimens were given the same vacuum anneal as for the decarburized specimens. The carbon content was determined from the maximum value of the internal friction carbon peak.2 Apparatus Fig. 1 shows a diagram of the tensile apparatus, with half the cooling coil removed. The cooling coil enabled temperatures from 200" to 77.2oK to be obtained. The apparatus was designed to fit a standard Tinius Olsen Universal tensile machine. The apparatus consisted of the rigid plate A which carried two carefully machined hooks H. These hooks attached the plate firmly to the moving crosshead of the tensile machine. The lower grip B was rigidly suspended from the plate A by three stainless steel rods. The upper grip C was joined to the upper grip of the tensile machine by the stainless steel rod E. The lower part of the apparatus was surrounded by a Dewar vessel, which was made a sliding fit inside the brass collar D. The specimen was held in a clamp which fitted into the grip, forming a ball and socket joint (see inset a). This was to attain as nearly pure

Jan 1, 1954

By Sam F. Harrison

Most hydraulic system malfunctions make their presence known by sending out warnings that are loud and clear to the initiated mechanic, according to Aeroquip Corp. service engineers. To detect problems in many systems, they suggest that the use of four senses-sight, smell, hearing and touch-and a knowledge of how to interpret the information gathered are all that&apos;s needed to identify hydraulic malfunctions.

Jan 3, 1978

By Ben L. Seegmiller

Localized open pit slope failure was avoided as an apparent result of a practical rock mechanics program conducted at the Twin Buttes copper operation. The key to the program was the application of cable bolting, a technique that artificially supports open pit slopes using properly installed post-tensioned cables. As a result of the research and testing program, extensions of the cable bolting principal became significantly apparent. • The economics of artificial stabilization appear to be overwhelmingly favorable, and • Best practical applications are "final" pit slopes, slopes beneath permanent structures and potentially slope failing areas. Success of this research is manifested by the fact that similar stabilization systems are presently under consideration for Twin Buttes as well as other open pit operations.

Jan 12, 1974

By C. F. Floe, M. Cohen, M. B. Bever, V. G. Paranjpe

P. Coheur and L. Habraken—We read this paper with great interest and are glad to congratulate the authors for their valuable work, supplying an important contribution to the mechanism of tempering on the carbides in vanadium steels. We are in a good position to appreciate this work since we have been studying, for more than a year, Cr-Mo steels of a composition similar, but less highly alloyed (namely 0.1 pct C, 3 pct Cr, 1 pct Mo). Our results are quite in concordance with the authors&apos;, however, we wish to point out that it is very interesting to use equally the electron microscope in order to observe the variations of microstructure in steels. We have studied simultaneously the evolution of the carbides in situ with the electron microscope, and, after extraction, again with the electron microscope, and then with X-rays. The first results which we have obtained have been communicated at the Congress of Delft (July 1949) and at the "Journees de la Metallurgie" in Paris (October 1949). These may be summarized as follows: After tempering with varying either the tempering temperatures or the tempering times, the carbides show two evolutions. The first one is connected to the carbides existing in the steels, principally in the boundaries of the grains. For some groups of steels these carbides may coalesce and for other groups they may

Jan 1, 1951