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By L. J. Dijkstra

During the past several years an extensive study has been made of the internal friction of iron containing carbon or nitrogen in solid solution.1,2,3,4,5 It has been found that a sharp peak is observed in a plot of the internal friction vs. temperature of measurement. With a frequency of about one cycle per second, this peak occurs at 20°C for N and 36°C for C. The physical origin of this anomalous internal friction was traced by Snoekl to the local tetragonal symmetry of the interstitial positions in body centered cubic (bcc) iron. A change in stress induces a change in the equilibrium distribution of the interstitial atoms among the three types of interstitial positions, the three types corresponding to the three directions along which the tetragonal axis may lie. It is the continual striving of the interstitial atoms to maintain an equilibrium distribution that gives rise to a phase lag between strain and stress during oscillation, and hence, to internal friction. A similar type of internal friction has been observed in the bcc lattice of tantalum containing in interstitial solid solution C, N or 06. The theory of this anomalous internal friction leads to the prediction that its magnitude is strictly proportional to the concentration of either the carbon or the nitrogen in solid solution, provided the concentrations are small. This prediction has been verified3 for the range of solubilities ohtainable in alpha iron. This proportionality provides us with a new tool for the study of nitrogen and carbon in alpha iron. It thus enables one directly to follow the precipitation of either of these solute atoms from solid solution and also directly to measure their solubility as a function of temperature. A preliminary study of precipitation using this method has already been presented by the author.3 The purpose of this paper is to present more extensive observations upon the precipitation of N and C in alpha iron, as well as to present observations upon the solubility of N and C in alpha iron which, at least in the lower tempera- ture range, are believed more accurate than those previously obtained by other methods. The interpretation of the observations upon precipitation involves the use of the appropriate equilibrium diagrams. For ease of future reference in this paper the equilibriunl diagrams for the Fe-N and Fe-C systems are accordingly reproduced as Fig 1 and 2, respective]y. Experimental Procedure The specimens were made of West-inghouse Puron iron and consisted of wires 0.025 in. in diam and about 1 ft long. By a wet hydrogen treatment the specimens were purified of C and N. In

Jan 1, 1950

By George F. Becker

Complexity of Rock-Fractures.—The strains to which rocks have been subjected are manifestly very complex, and it is entirely safe to presume that every possible mode of deformation and rupture is exemplified. The most superficial inspection of any ordinary mountain region is sufficient to assure the observer that the rocks have been pressed, stretched, bent, buckled, twisted, and shorn. The study of torsional rupture cannot fail, therefore, to throw light on geological phenomena. The question is how areas which have been broken in this manner are to be distinguished from those which have yielded to other systems of forces. Phenomena of Joints.—It is well known that a large part of the more homogeneous rocks and some very heterogeneous rocks are intersected by partings often ailed joints. These partings are frequently flat surfaces even when seen in very large exposures, but are sometimes surfaces of moderate, single, or double curvature. Joint, usually occur in groups, in each of which the several partings are parallel to one another, and several such groups often intersect the same rock-mass. In such cases the different systems make large angles with one another. Nearly all students of the subject of jointing have reached the conclusion that joints are faulted surfaces, the dislocations usually being of small amplitude; and this conclusion receives abundant support from the study of thin sections under the microscope. It has thus been shown that much even of what would be regarded in hand specimens as mere slaty cleavage

Jan 1, 1895

By T. A. Read, M. W. Burkart

The crystal geometry of the cubic-tetragonal interface after partial transformation of an indium-thallium alloy single crystal is described and a general theory is presented. The effects of applied stresses on this transformation are interpreted and the latent heat of transformation is obtained from observations of transformation under stress. A DIFFUSIONLESS phase transformation between face-centered cubic and face-centered tetragonal structures has been reported for the indium-thallium system by Bowles, Barrett, and Guttman1, 2 The transformation takes place at approximately 105 "C at 18 atomic pct Tl and 25°C at 23 pct Tl. In their study, Bowles, Barrett, and Guttman used poly-crystalline samples whereas in the present study single crystals were used to eliminate the transformation constraints imposed by adjoining grains. The use of single crystals made possible a comprehensive study of the effect of stress on the transformation. In the course of the work, it was possible to formulate a new method of analyzing dif-fusionless transformations (presented in this paper) which permits calculation of the geometry of the interphase interface from a knowledge of the crystal structures of the initial and final phases. The specimens were prepared from chemically pure thallium and 99.97 pct In which were weighed out to produce 3 to 4 grams of alloy of the desired concentration. The metal was placed in clean fused silica tubing, then melted, degassed and sealed under vacuum. (To obtain single crystals, it was found that both degassing and extreme cleanliness were essential.) Single-crystal specimens were grown by a modified Bridgman technique.8 pecimens were removed from the tube by dissolving the quartz in concentrated hydrofluoric acid which attacks the specimen very slowly. The specimen then was polished mechanically to produce four flat surfaces, electropolished, and annealed at 140°C for 48 hr. The electropolishing solution used was that described by Bowles, Barrett, and Guttman and the polishing was carried out on both the high and low temperature phases of the alloy. The high temperature polishing was done at 110°C with a stainless steel cathode. Visual Observation of the Transformation in Single Crystals A visual study of the transformation was made on specimens which had been electropolished in the high temperature phase. The specimens were supported on the stage of a metallograph by an electrically heated holder which contained an opening for observing the specimen. Visual evidence of transformation was found in the presence of an interface which separated the two phases. The interface plane defines the boundary of the phase undergoing transformation and manifests itself by the sharp change in angle between the surface of the specimen and the incident light at the juncture of the two phases. On slow cooling, well-annealed specimens transformed from the face-centered cubic structure to the face-centered tetragonal structure by the motion of a single plane interface which traversed the specimen from one end to the other. Upon heating, the interface moved back in the reverse direction. The interface could be started, stopped, or reversed at will. A temperature hysteresis of about 31/2oC was observed in the reversal of the interface. Holding an interface stationary caused it to disappear completely in most cases, whereas in other instances the interface became less distinct depending upon its orientation. The interface could be made to reappear by changing the temperature of the specimen. The low temperature tetragonal structure exhibits only the fine markings or subbands reported by Bowles, Barrett, and Guttman and is illustrated in Fig. 1. These subbands are twin-related. Back-reflection Laue patterns show the breakup of the cubic spots into pairs of spots corresponding to the twin orientations of the tetragonal phase.

Jan 1, 1954

By H. S. Rankin, E. C. Houston

OLIVINE is considered a valuable potential source of metallic magnesium in the chloride electrolytic process. Treatment of olivine with hydrochloric acid can be carried out under conditions that prevent the formation of gelatinous silicic acid, which would inhibit the reaction by forming a covering around the ore particles. It is our hypothesis that the formation of gelatinous silicic acid is avoided by the dehydrating action of the magnesium chloride, which takes up water to form a series of hydrates and leaves the silicic acid in granular condition. Leaching serves to separate the magnesium chloride from the silicic acid and unattacked ore, which can be treated with fresh acid in successive steps until extraction is essentially complete. The leach solution can be purified by the addition of caustic magnesia and the precipitated impurities removed by decantation or filtration. The resulting magnesium chloride contains: Fe, less than 0.001 per cent; Mn, 0.012 per cent; Ni, none. Chlorination[f] of olivine has two major defects: (1) a large part of the chlorine goes to form silicon and iron chlorides, (2) the anhydrous magnesium chloride is held by absorption in the finely divided silica. SUPPLY It is well known that olivine, a silicate of magnesium and iron, is present in large amounts in several localities in the United States. The largest deposits occur in the southeast and on the Pacific Coast.1 The southeastern deposits were surveyed by Lewis2 in 1896 and by Hunter3 in the period 1933-1940. It is estimated that high-grade olivine, conveniently located with regard to transportation and power, is present in excess of 230 million tons above local drainage level in western North Carolina and north Georgia. PREVIOUS TECHNICAL WORK In the past few years, olivine has attracted considerable attention in the refractory field. In the chemical processing industry, however, it has long been thought axiomatic that the cost of processing silicates is an economic barrier to their utilization, especially where more reactive minerals, such as carbonates, oxides or salts, are available. This attitude is not entirely justified in connection with olivine. Unlike most silicates, olivine is readily attacked by acids, chlorine and other reagents without resorting to fusion to break down the silicate structure. Olivine has been suggested as a raw material for making epsom salt by roasting with pyrites.4 Other processes include acid treatment5 and digestion with calcium chloride.6 Recently a small plant was built near Webster, N. C., for making epsom salt from olivine by treatment with sulphuric acid. This plant is now in commercial operation, producing approximately two tons per day. Olivine is also receiving attention from the fertilizer industry as an inexpensive source of soluble magnesium.

Jan 1, 1942

By P. A. E. Armstrong

For hardening, the steel should be heated just above the critical temperature, as a properly forged steel quenched from this heat has some toughness, with maximum hardness and density. The quenching bath should be kept at approximately a constant temperature. In drawing or tempering, longer time periods at lower temperatures are better than the shorter periods at higher temperatures. A recent questionnaire brought out the following facts: The double-arc, double-taper bit and cross bit give the best service; resharpening of the drill steels most frequently was caused by wear of gage; chipping of bit was, with one exception, the second cause; breakage of shank was with one exception, the third cause; upsetting of bit, upsetting of shank, and breakage of body were the fourth cause. The direct cause of the necessity of resharpening given was poor heat treatment first, and faulty steel and severe rock conditions second. Rock-drill Steel By N. B. Hoffman Much of the drill steel produced in America is manufactured into hollow rods. After all forging has been finished the entire bar should be thoroughly annealed and heat trcated before the point is hardened and tempered, at least where the drill has heavy duty, such as working in deep holes and hard rock. A large number of tools of like character and doing work requiring similar properties are now being made of alloy steels; for instance a steel with a carbon content of 0.75 to 0.85 per cent., manganese 0.25 to 0.35, phosphorus under 0.020, sulfur under 0.030 and vanadium 0.18 to 0.23 has proved very satisfactory for chisels. A steel of this type properly manufactured will be far superior to the ordinary carbon steels, while at the same time is one whose price range should not prove prohibitive. Much of the cutting efficiency of a drill depends on proper heat treatment. This vanadium steel has a far greater safe hardening and forging range than ordinary carbon steels, making it more nearly foolproof. It will harden nicely at 1400" I?. but will also harden well and satisfactorily at 1550" F. retaining its quality of hardness and toughness in either case. Drill Steel from Hollow Ingots BY P. A. E. ARmstrong Hollow drill steel is made from a drilled billet with a sand-filled core or the drilled, pierced, or the drilled and pierced billet, not sand-filled, is rolled down over a projectile or ball much the same as in ordinary pipe manufacture. The first is the method generally used in this country; the second is used largely in Sweden. Swedish hollow drill steel has a

Jan 1, 1922

By R. H. B. Jones

THIS paper reviews pertinent geology of the Biwabik iron formation, Mesabi Range, Minnesota. This iron formation is divisible into four members. Each member is distinctive and contains marker horizons, which are recognizable throughout all phases of alteration from lean, fresh rock to high-grade iron ore. Some beds have a larger magnetite content than others. During the process of ore genesis, which is essentially an oxidation process, the magnetite content is lowered. Alteration from iron formation to ore includes both oxidation of iron minerals and silica removal by leaching and these distinct processes progress at variable rates for different locations and structures. Magnetic intensities, of each horizon of the iron formation are dependent chiefly upon its preoxidation magnetite content, upon the subsequent degree of oxidation, upon the character of the enclosing rocks, and on the extent of fracturing, folding, or faulting. The results of a number of magnetic surveys are described and are correlated with results of drill-hole and mine exploration and development. The magnetic anomalies obtained are discussed in relation to phases of formation of ore within the iron formation.

Jan 1, 1946

By Nick Warren

The problem considered is that of predicting rock physical properties from observations of the structure of the rock. The approach here departs from previous studies in that both the physical properties and structural features are taken as statistical data and the relations between them are cast as statistical functions. This approach I have termed a "quantitative petrostructure analysis". This Paper deals with two aspects of making such a study; parameterizing patterns of topographic features of rock, and characterizing variables to allow correlation studies to be carried out. The principle of a quantitative petrostructure analysis is outlined and illustrated using maps from two samples of Conway granite.

Jan 1, 1982

By D. Swan

Industrial research may be defined as a critical and exhaustive investigation to create new and better ways of doing things. The results of industrial research are new and improved products, processes, and techniques. This broad definition, of course, covers investigation of all subjects by either individuals or groups of people, and this chapter aims to examine the purpose (what research tries to do), and methods (or how research is done) as applied in the mineral industries. Concepts and History The idea or concept of organized research probably originated in the universities of Europe. There, groups of scholars banded together for discussion and application of their particular specialty to a common problem. Publication of the conclusions drawn from such investigations gave scholars in other areas the opportunity to review and criticize the work of their colleagues, and one of the hallmarks of scientific research work is the publication and criticism of the results of the investigation. It was not until the late nineteenth century that the concept of organized research for the profit of industry was recognized. During the late nineteenth and early twentieth centuries, a large number of industrial enterprises sponsored organizations to study the application of the physical sciences with the aim of making discoveries that would result in profit to the sponsoring organization. The tangible benefits accruing from these activities were so great that they, in turn, fostered several other methods for the support of organized research activities. For the large problems involving public interest, United States Government scientific research laboratories were set up. As the demand of smaller enterprises for research activities increased, research institutes and consulting laboratories were organized. In Europe the idea of common industry sponsorship of research centers grew and many large research organizations there were sponsored by associations of manufacturers. Finally, in the United States

Jan 1, 1964

By Edgar Bain

OF THE important phenomenon of the hardening of steel, Professor Sauveur1 says: "It would seem as if the methods used to date for the elucidation of this complex problem have yielded all they are capable of yielding and that further straining of these methods will only serve to confuse the issue, the point having been reached when this juggling, no matter how skilfully done, with allotropy, solid solutions, and strains is causing weariness without advancing the solution of the problem.. The tendency of late has been to abandon the safer road of experimental facts and to enter the maze of excessive speculations, in which there is great danger of some becoming hopelessly lost. The conclusion seems warranted that new avenues of approach must be found if we are to obtain a correct answer to this apparent enigma. With some degree of fitness we may say, this of other problems. It seems likely that one of the new avenues of approach to many metallographic problems is the study-of crystal structure, or more accurately, the atomic arrangement by means of the X-ray spectrometer. The crystal structure of some materials has been carefully worked out by the mineralogist, but his methods are, in general, unsuited to commercial metals and a method that yields even better information is at hand as the result of work on the diffraction of X-rays by Laue and the Braggs2 and later by Hull,3 St. John, and others. It should be understood that the contour of free crystals, which is the subject of measurements by the crystallographer, is the result of the atomic structure and, in general, bears a simple and obvious relation to it. The use of the X-ray spectrometer4 has been described frequently, so the procedure will not be given here.

Jan 2, 1922

By N. K. Chen, R. Maddin, K. T. Aust

Lattice rotations occurring on the tension and compression sides during the bending of molybdenum single crystals at room temperature were followed in detail. Observations were also made concerning crystallite rotations and slip traces. &apos;The results indicated the participation of (110) as slip planes and the<111>as slip directions. Crystallite fragmentation during bending was also noted. EVERAL investigations have been conducted on pure bending of face-centered cubic metals.&apos;-" Structural changes as a result of "bend-gliding," and the importance of bending and constraints during conditions of axial stressing, have been noted.&apos;," It was evident that the mechanism by which the bending deformation occurs is more complex than the case of simple shear. Studies of the bending of body-centered cubic metals from the aspect of the crystallographic mechanism appear to be lacking. Molybdenum single crystals therefore were subjected to deformation by bending in order to determine the reaction of the body-centered cubic lattice to bending stresses. It might be expected for the bending of single crystals that lattice rotation as represented by the axis of compression would proceed toward the pole of the active slip plane and that rotation of the tensile stress axis should indicate the slip direction.&apos; It was believed therefore that a study of the tension and compression sides of bent molybdenum single crystals should give data concerning the operative slip system. Specific problems which are pertinent to the overall picture of plastic deformation were also investigated, e.g., whether the constraints offered by pure bending give rise to the deformation band, and also the nature of the asterism occurring on the tension and compression sides during the stages of deformation. Experimental Procedure Eight single crystal specimens were grown from sintered molybdenum rods 143 in. diameter using the method described previously.6 The purity of this material was reported as 99.9 pct as described elsewhere.&apos; The specimens were % to 1/10 in. in diameter x 7 in. long, with single crystals approximately 1 to 2 in. in length occupying the entire center sections of each specimen. The specimens were elec-trolytically polished using an electrolyte of 300 cc methyl alcohol, 60 cc H2SO4, 130 cc HCl, and a current density of 4 amp per sq in. Each specimen was then loaded in a bending apparatus similar to that used by Yen and Hibbard,&apos; as shown in Fig. 1. The load was applied by means of a spring and screw arrangement through four ball-bearing surfaces set 1.5 in. apart. Either the inner two bearings or the outer two (A, B, Fig. 1) were attached to a movable steel plate (D) through which the load was transmitted. Since the apparatus was mounted on a track of the X-ray apparatus, the tension or compression side of the specimen could

Jan 1, 1954

By A. A. Jr. Smith, J. S. Smart

Numerous investigations of the effects of the various impurities common to commercial coppers have been published, and the data have found wide use in industry. Naturally, emphasis has been placed on the oxygen-bearing coppers of the tough-pitch variety, but need is now evident for data covering the oxygen-free condition as well. Furthermore, relatively few of the important reactions between oxygen and the various impurities are well understood, and often the data at hand are not applicable to the low concentrations encountered in commercial coppers. This paper presents the changes in conductivity and softening temperature derived from individual additions of the group VIII triad, iron, cobalt and nickel, to high-purity copper, and constitutes a portion of the copper-research program being conducted at the Central Research Laboratory of the American Smelting and Refining Co. The method of preparation of high-purity copper and its alloys in either the oxygen-free or oxygen-bearing form has been described previous1y.l The purity of this material, and the methods developed to produce it, provide the means for direct investigation of the very low concentration range in which the various impurities generally exist in commercial coppers. The usual necessity for extrapolation to this range using the results obtained from higher concentrations, and the interfering effects of extraneous impurities, are thus simultaneously circumvented. Since previously published data have adequately presented the effects of higher concentrations of iron, cobalt and nickel, the present investigation has been confined to the composition range o to 0.05 per cent. All alloys were initially prepared in the form of oxygen-free continuous cast rod, the weighed alloying additions in suitable form being charged with the pure copper to the continuous casting crucible. The best of the available high-purity alloying materials were used, and spectrographic analyses confirmed the absence of interfering elements from the alloys formed. Each series was compounded in the direction of increasing concentration, starting with pure copper in a new crucible and finishing with the 0.05 per cent alloy. Composition was closely controlled by adding the alloying element in the form of a carefully compounded and analyzed master alloy rendered uniform by continuous casting. The accuracy of this method of synihesis was proved by chemical analysis of the more concentrated alloys, and, accordingly, there is every reason to credit the stated composition of the very dilute alloys in the range where chemical analysis becomes highly uncertain. Oxygen-free samples for measurements of conductivity and softening temperature Were obtained by drawing the continuous cast rod to wire of 0.08I-in. diameter. employing a number of intermediate anneals to refine the grain structure. The

Jan 1, 1942

By A. A. Jr. Smith, J. S. Smart

Numerous investigations of the effects of the various impurities common to commercial coppers have been published, and the data have found wide use in industry. Naturally, emphasis has been placed on the oxygen-bearing coppers of the tough-pitch variety, but need is now evident for data covering the oxygen-free condition as well. Furthermore, relatively few of the important reactions between oxygen and the various impurities are well understood, and often the data at hand are not applicable to the low concentrations encountered in commercial coppers. This paper presents the changes in conductivity and softening temperature derived from individual additions of the group VIII triad, iron, cobalt and nickel, to high-purity copper, and constitutes a portion of the copper-research program being conducted at the Central Research Laboratory of the American Smelting and Refining Co. The method of preparation of high-purity copper and its alloys in either the oxygen-free or oxygen-bearing form has been described previous1y.l The purity of this material, and the methods developed to produce it, provide the means for direct investigation of the very low concentration range in which the various impurities generally exist in commercial coppers. The usual necessity for extrapolation to this range using the results obtained from higher concentrations, and the interfering effects of extraneous impurities, are thus simultaneously circumvented. Since previously published data have adequately presented the effects of higher concentrations of iron, cobalt and nickel, the present investigation has been confined to the composition range o to 0.05 per cent. All alloys were initially prepared in the form of oxygen-free continuous cast rod, the weighed alloying additions in suitable form being charged with the pure copper to the continuous casting crucible. The best of the available high-purity alloying materials were used, and spectrographic analyses confirmed the absence of interfering elements from the alloys formed. Each series was compounded in the direction of increasing concentration, starting with pure copper in a new crucible and finishing with the 0.05 per cent alloy. Composition was closely controlled by adding the alloying element in the form of a carefully compounded and analyzed master alloy rendered uniform by continuous casting. The accuracy of this method of synihesis was proved by chemical analysis of the more concentrated alloys, and, accordingly, there is every reason to credit the stated composition of the very dilute alloys in the range where chemical analysis becomes highly uncertain. Oxygen-free samples for measurements of conductivity and softening temperature Were obtained by drawing the continuous cast rod to wire of 0.08I-in. diameter. employing a number of intermediate anneals to refine the grain structure. The

Jan 1, 1942

Since 1571, when the Institute was founded, many of the most important papers in the English language, on the various phases of mining and metallurgy, have appeared as Institute publications. As members of the Institute regularly receive the publications in which they are interested, this discussion is primarily for nonmembers who wish to know of them. The Institute has several means of issuing papers which have been submitted and accepted. The monthly journal, Mining and Metallurgy, is the magazine of the Institute. In it appear notices and reports of official business as well as many papers and contributions which do not appear otherwise. The annual subscription price of the magazine to nonmembers is $3 per year; Canadian and foreign postage $1 extra; single copies 50 cents; back issues $1 each. Many papers are published separately each year. They are issued in one or the other of two numbered series; namely, Technical Publications and Contributions, and of the latter there are four forms: Preprints, Mimeographs, Reprints, and Unpublished Manuscripts. A Technical Publication or Contribution (in any form) is issued by the Institute when it is listed in Mining and Metallurgy. Technical Publications are sent automatically to members who have asked in advance for papers on a given subject. All members are entitled to a copy of every paper in either series, except when a Contribution is an Unpublished Manuscript. Con¬tributions in the form of Unpublished Manuscripts are filed in the Engineering Societies Library and copies of some of these papers may be found in a few selected libraries throughout the country.

Jan 1, 1933

By E. A. Holbrook

RESEARCH, primarily, is finding out the truth. Research applied to engineering opens the door to new principles and processes, the application of. which benefits mankind in a material way. The engineer believes that investigation instituted with the primary view of making the results directly applicable to the industries is the highest type of research. Coal is essentially the basis of modern industrial civilization; therefore, any, considerable research pertaining to coal must link itself to the industry by, practical application of the results of the research. In other words, all investigational work connected in any way with coal leads to conclusions that permit a better understanding of the origin, nature of occurrence, composition, better and safer mining, more careful preparation, or greater efficiency in utilization of coal. Modern engineering research has been fostered essentially by universities and in the laboratories of institutions of learning. Coal problems that lend themselves to solution in the laboratories have been first attacked and are perhaps the farthest toward solution. For example, a great amount of research work has been carried out with the various phases of chemistry connected with coal. On the other hand, the equally important problems connected with methods of mining have received but little attention, primarily because their solution involves the continued use of a great and expensive laboratory, which is none other than the mine itself. As many of the problems already solved have had chemistry as their background, so many of the problems unsolved have physics as their background; there are also unsolved problems that deal in- coal economics. Even psychology must be called upon in future coal-mining research as a basis for solving those great problems that deal with human relationships. In general, considerable advance has been made in coal research dealing with chemistry, not so much progress has been made with problems having physics and engineering as a background, while there is a tremendous range of untouched problems that deal essentially with business and psychology.

Jan 9, 1919

By David Reger

Introduction THE exhaustion of oil and gas in the United States is proceeding at a rapid pace. This is especially true in fields where the light oils that furnish the most fuel for internal-combustion engines are found, leading to a late estimate by Arnold that the petroleum resources are 36 per cent. exhausted.1 The further remark by Dr. David T. Day at the New York meeting of the Institute, in February, 1916, that the operators of the country are now scarcely able to supply the ever-increasing demand for gasoline, leads the writer to believe that a determined effort will soon be made to secure deeper producing horizons in those regions that now furnish high-grade oil, and in which pump stations and pipe lines offer convenient means for the economical handling of new production. A study of Arnold&apos;s table shows further that the States that produce paraffin oil exclusively are 45 per cent. exhausted, this figure being much higher than the average of paraffin and asphalt States altogether. The most extensive of all the paraffin-oil-producing areas is the Appalachian Field, extending with the Appalachian Geo-Syncline from western New York southwestward through western Pennsylvania, western West Virginia, Ohio, Kentucky, and Tennessee, where oil of high gravity is always secured. Of these States, Pennsylvania and West Virginia rank highest in. the quality of their product. In West Virginia, the oil sands dip to a lower level than in any other locality in the Appalachian Geo-Syncline, the Pittsburgh Coal of the Pennsylvanian being only 50 ft. above sea level along the Nineveh Syncline at Wileyville, Wetzel County.2 The very significant fact that the sands of the Mississippian and Upper Devonian Measures furnished the richest oil pools of the State along this

Jan 9, 1916

By G. E. Pralle

INTRODUCTION The decade from 1969 to 1979 saw the crest of a wave of investments by companies and investors, primarily from the major industrial nations, in the metals and minerals industries of the so-called lesser developed countries. This was brought about by two major considerations: 1). The higher ore grades and therefore the higher profit potential of the mineral deposits in the third world countries, and 2). The desire, particularly by the European countries and by Japan, to ensure a safe supply of raw materials not available in their own countries. The decade began with the start of the Toquepala mine in Peru and the major investments in the Bougainville mine in Papua New Guinea and the Ertsberg mine in Indonesia. It ended with the start-up of Southern Peru Copper Company (SPCC) Cuajone mine in Peru and Inco&apos;s Soroako mine in Indonesia and the investments in several major alumina or aluminum projects in Australia and Brazil. Concurrent with this huge flow of funds into the mineral resources industry of the developing world was the build-up of a psychological fear in the host countries of exploitation/domination by the foreign investors. This resulted in an increasing trend towards: 1). Nationalization of existing mineral ventures, and 2). Tougher legal/fiscal frameworks for new ones. NATIONALIZATION Nationalization appeared in its earliest form as "Mexicanization" of the petroleum industry in Mexico in the 1930&apos;s, followed later by Mexicanization of the mining industry in general. This was enacted with the Mexican Mining Law of 1961 which required that 51% of the equity be owned by Mexican nationals. Later in the decade the equity share for foreign investors was reduced to 33 1/3% for the developers of the Frasch sulphur operations in the Isthumus of Tehuantepec. However, the law was not fully implemented in the copper industry until late 1970 with the purchase of 51% of the ownership in the Cananea Mining Company. The trend toward nationalization of the copper industry progressed to Chile where in 1967 under the Government of Eduardo Frei the major North American copper companies were induced to sell a one-half interest in their Chilean mines to the State. Likewise, in 1970, "Zambianization" took place, when the two major operating companies Roan Selection Trust (Amax) and Zamanglo (Anglo American) were restructured into Roan Consolidated Mines (RCM) and Nchanga Consolidated Mines (NCCM) providing the government with 51% of the equity ownership. Whilst the earlier forms of nationalization in general constituted a fairly priced buy-out (El Teniente, Chile for US$80 million, RCM for US$117.8 million, NCCM for US$178.7 million), the total nationalization of the Chilean mining companies in 1970 under Salvador Allende did not. Later, "Western" countries joined this trend and on October 29, 1973, Mr. Gough Whitlam proclaimed that "overseas capital must continue... in partnership with Australian capital" and "in some special energy cases we have an objective of 100% Australian ownership". In 1974 Mr. Pierre Trudeau stated: "The Liberal Party of Canada sets as an objective that new resources projects in the natural resource field should have at least 50% and preferably 60% Canadian equity ownership". FOREIGN INVESTMENT The situation for the foreign investor in the worldwide resource industry rapidly deteriorated from then on. New features appeared in mineral exploitation and operating agreements, centering not only on local government/local companies ownership but also on increased taxation. The new tax rate (mineral tax, royalty, and income tax) for the semi-government companies NCCM and RCM in Zambia became an effective 73%. Likewise the much publicized and discussed renegotiated Bougainville agreement brought dramatic increases in the total "take" by the PNG Government. More innovative forms of indirect taxation made their appearance and were added to the normal tax burdens of the mineral industry which already

Jan 1, 1985

By Paul C. Ragland, P. Geoffrey Feiss

The Piedmont province of the southern Appalachians is the focus of interest for many exploration geologists. In the past, only those deposits with significant surface exposure were exploited. Thus, few deposits have been found and relatively little exploration has been conducted in recent years. Modern geochemical and geophysical techniques can alleviate this problem of concentrating on exposed ore bodies by allowing us to "look through" the soil and saprolite to detect the presence of significant mineralization at depth. This paper will attempt to evaluate the feasibility and effectiveness of several geochemical exploration techniques in the Piedmont province of Cabarrus and Stanly counties, N.C. The area chosen for study is shown in Fig. 1, lying almost wholly within the Mt. Pleasant quadrangle, N.C. The area is on the eastern boundary between the Charlotte belt, a zone of plutonic and intermediate grade metamorphic rocks, and the Carolina Slate belt, a series of complexly interbedded volcanic and sedimentary rocks of predominantly low metamorphic grade. The area is considered to be an early Paleozoic active, continental margin. 1 As is typical of most of the piedmont, outcrop is sparse. Figure 2 is a sketch map of the general geology of the area under study, showing the Charlotte belt rocks in the north-western quadrant and slate belt rocks to the east. Within the area are a number of old mines and prospects, the most famous of which are the Furniss and Phoenix mines in Cabarrus County. All are reported to have contained Au and Cu. Ag and Pb were reported from some. A summary of the deposits is given in Table 1.

Jan 6, 1979

By J. Versluys

A well can flow exclusively through the casing or exclusively through a tubing but can also flow partly through a casing and at the top part through a tubing. The main principles of the flowing of wells under these conditions were explained in the author&apos;s former paper.&apos; Practically all factors that influence the regular flow are dealt with therein. The question of irregular flow, however, will be discussed briefly here. As a rule, an irregular flow must be avoided, as it may be assumed that the efficiency is thereby very small, while on many fields it is injurious to the sand of the oil-bearing layer. Periodical flowing often occurs with rising mixtures of gas and liquid. The phenomenon can be explained if it is accepted that two conditions are possible in the mixture; namely, the foam condition and the mist condition. If there is no stabilizer in the liquid, the foam condition can exist only when the liquid forms a greater portion of the volume than the gas. The mist condition, on the other hand, can exist only when the liquid occupies a smaller part of the volume than the gas. The foam condition occurs when there are gas bubbles in the liquid mass, while in the mist condition drops of liquid are disseminated in a gas-filled space. For sake of simplicity, it has been assumed that the mist condition prevails when 50 per cent. or more of the volume is occupied by gas, while with less than 50 per cent. gas the foam condition will arise. For distilled water and for oils which do not tend to form stable foams this is probably approximately true. If this does not hold good, however, two cases are possible: (1) The fields of the two conditions overlap or (2) they do not meet. If the fields of the conditions overlap there is an intermediate field where either of the two conditions can exist, depending on the history of the mixture. Suppose the foam condition prevails first and the gas

Jan 1, 1931

By T. S. Fuller

Various phases of the embrittlement of solid copper containing oxygen by the action of reducing gases at high temperatures are familiar to readers of metallurgical literature through the work of many experimenters. In 1900, Heynl recorded observations of copper being heated in hydrogen with the development of fine cracks, the result of the formation of steam within the metal through the action of hydrogen on the copper oxide usually found in copper. Archbutt,2 in 1905, published the results of experiments, showing that all oxygen can be removed from copper by heating to redness, for several hours, in hydrogen. Intercrystalline cracks and extreme brittle-ness developed. Archbutt attributed the brittleness to the reduction of oxides present in the copper. Bengough and Hil1,3 in 1910, encountered the now well-known embrittlement at the outset of their investigation and stated in their paper: It soon became evident that the effect of any heat treatment depended largely on the presence or absence of reducing gases in the atmosphere of the furnace, as well as on its temperature. Hence it became necessary to adopt a somewhat elaborate scheme of heat treatment. The authors found embrittlement in separate experiments due to both hydrogen and carbon monoxide and concluded that: "The gases ruin the alloys after being heated to about 650" C. in their presence." Ruder,4 in 1916, reported the results of a series of experiments made by heating commercial and deoxidized copper in hydrogen, carbon monoxide, carbon dioxide, and steam. In agreement with other writers, he found that copper containing oxygen was made brittle by reducing gases, while the deoxidized metal remained unaffected. In the case of

Jan 1, 1926

By Christopher Haycocks, Michael Karmis, David G. Lundy

Roof bolting is the most common means of support in under- ground coal mines. The main advantages of this support system are the relative ease of installation and the ability to provide a stable and unobstructed work area. Roof bolts can be broadly classified into two categories, mechanical and resin bolts. Currently, about 20% of all bolts used are the resin types, and trends show an increasing popularity of these kinds. Although the reinforcing effects of resin bolts have been well demonstrated, there is, nevertheless, a considerable lack of knowledge of their interaction with the surrounding strata. To study this interaction and to further investigate the mechanisms involved in resin bolting, an instrumentation system was designed and tested in a southwestern Virginia coal mine. The instrumentation system was composed of straingaged resin bolts, convergence and differential sag stations, and a borescope. Strain gages mounted on the bolt determined axial, bending, and shear strain at several levels along the axis of the bolt. The roof movement, as measured by the convergence and differential sag readings and as observed by the borescope, correlated well with the strains registered on the bolts.

Jan 1, 1983