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By J. P. Hammond, C. J. McHargue, J. R. Holland

IT has been reported that both berylliumL and zirconium&apos; developed the same basic textures during rolling at temperatures up to 1475 °F as at room temperature, differing only by an increase in the spread of basal planes toward the transverse direction as the temperature of deformation was increased. Iodide titanium&apos;&apos; rolled at 1050°F has a texture similar to the cold-rolled texture, {000l}, 25° to 30" from the rolling plane toward the transverse direction, <1010>, Rolling iodide titanium at 1450°F produced a more random condition with the basal planes parallel to the rolling plane and no direction strongly aligned with the rolling direction.

Jan 1, 1957

By L. F. Mashburn, T. J. Ferree

A Reichert cone concentrator was installed in an aggregate plant circuit to recover the extremely fine "flour gold" known to exist in the deposit. The gold content of the bank- run gravels averages about 0.1 g/t-about $1.29/t, based upon $12.86/g ($400 per oz) gold. The fineness of the gold averages between 950 and 960. The Reichert cone, in conjunction with a conventional shaking table, recovers in excess of 85% of the gold. A screen analysis of the gold particles shows 44.1 % is - 74pm (-200 mesh) in size. The plant operates with a two-man crew.

Jan 1, 1983

By AIME AIME

PERHAPS the most interesting paper of the subsidence session on Monday morning was that by Roland D. Parks entitled "Yieldable Metal Props for Underground Support." This paper described the development of a telescoping prop made from two pieces of pipe. The lower and larger in diameter has cast in it a soft metallic alloy which is slowly extruded through an orifice in the upper and smaller piece of pipe. In this way, the length of the prop decreases gradually as the load from the roof increases. The stress-strain diagram for these props, as tested in the laboratory, is almost ideal, and can be duplicated satisfactorily in successive tests. They have not yet been tested underground. Another paper of much interest was presented by Prof. P. B. Bucky. It is an addition to his series on structural models as applied to mining and was entitled "Effect of Approximately Vertical Cracks in the Behavior of Hori¬zontally Lying Roof Strata." It was illustrated by motion pictures of a model under test. After explaining the un¬derlying theory, the apparatus and the mode of testing, Prof. Bucky set forth the effect of vertical cracks in a mine roof, as follows: (a) the wider the crack, the weaker the roof; (b) where the sides of the crack are in juxtaposition, there is little weakening of the roof; (c) grouting cracks whose sides are not in contact restores the strength of the roof until it may be as strong as, or stronger than the uncracked roof. Small paper props helped sustain the roof. Both the nature of the material and its bonding affect its behavior under stress.

Jan 1, 1933

By J. H. Jackson, P. D. Frost, C. H. Lorig, L. W. Eastwood, A. C. Loonam

R. S. BUSK*—I wish first to congratulate the authors of this paper both for the work done and the presentation of that work. We have also been working on this type of alloy development, but any technical contribution I might have is better reserved for a separate paper which is planned in the near future. However, I would like to insert a word of caution. The alloys described in this paper are still very much in the laboratory stage. There still remains the quite vexing problem of property stability at slightly elevated temperatures which must be solved before the properties quoted can be effectively utilized. These alloys are extremely interesting and I am confident that the problems can be solved. However, the present existence of those problems must not be overlooked. I have one question with regard to the work-hardening test. If the work harden-ability of magnesium is compared to aluminum using a more standard test such as the Meyer Analysis the magnesium is found to work harden the more rapidly. Is the test developed for this work truly a work-hardening test or a measure of something else ? J. H. JACKSON (authors&apos; reply)—I am sure we appreciate the comments of Mr. Busk and we are pleased that the Dow Chemical Co. has also undertaken work in this field. It is a big field. We, of course, are continuing our research for the Navy Bureau of Aeronautics, since, as clearly shown in the paper, the alloys are not completely developed. With regard to Mr. Busk&apos;s comments on the relative work-hardenability of aluminum and magnesium, the comparison we cited in the paper was intended merely to show that the results obtained by our method of testing were independent of the yield strength of the materials. We believe that this test method afforded a rough indication of the work-hardenability of the magnesium-lithium base alloys. It is not known whether this method affords greater or less accuracy than the Meyer Process, which is based upon a hardness-test impression. It is quite possible, since work-hardenability is a function of metal purity, that our results, obtained for commercial aluminum and magnesium, would be different if high-purity metals had been used. A. C. LOONAM—Lithium has some very interesting effects on magnesium. The paper showed that even small percentages increased ductility. These small amounts changed the axial ratio of the hexagonal magnesium from 1.624 in the pure metal to 1.606 in the saturated alpha solution, a value close to that of titanium, which has a ratio of 1.601. You will recall an article in the January, 1949, issue of the Journal of Metals where it was stated that titanium can be cold-rolled over 90 pct without any significant edge cracking. At 4.9 or 5 pct lithium, a change begins in crystal structure—from a hexagonal close packed to body centered cubic. There are two phases over a short range of lithium content, but at 10 pct the structure becomes completely cubic. The melting points of alloys in this range of lithium content are relatively high. Alloys even up to the six ratio have melting points above 500°C; this represents a relatively small reduction in melting point from pure magnesium itself. The magnesium-lithium system has a number of very interesting characteristics. This is only a very small part of the story. J. H. JACKSON—I would like to remind you that Mr. Loonam is one of the authors of this paper, and the fact is that this work is based on many of his ideas. I am sure we appreciate his additional comments in this discussion. R. LEITER*—I am interested in Fig 19 in which Mr. Jackson compares

Jan 1, 1950

By AIME AIME

ALTHOUGH the present economic depression is felt in the petroleum industry, probably as much as in any other branch of American industry, the Petroleum Section of the Institute was well represented at the general sessions on Monday and at all of the seven division sessions on Tuesday, Wednesday and Thursday. The seven sessions of the Division were so arranged as not to conflict and thus permitted members to hear the programs of all sessions.* The first meeting of the Petroleum Division was held on Tuesday afternoon; a joint session on engineering research and production engineering. The following papers were presented:

Jan 1, 1931

By D. D. Pollock, D. I. Finch

Relationships between the compositions of specially prepared manganin-type alloys and some of their electrical properties have been established. Empirical equations, based upon the electronic configurations of the alloying elements, are given which describe the resistivity, temperature coefficient, peak temperature, and thermoelectric power of Cu-Mn-Ni-Fe alloys at approximately room temperature. Calculations based upon these relationships are correlated with experimental data. SECURING suitable alloys for the construction of stable resistors, for use in precise electrical measuring devices, has been important ever since the art of electrical measurement was begun. German silver, Pt-Ag, and Platinoid are examples of some of the alloys in early use. These early alloys were un- satisfactory for one or more of the following reasons: l—insufficient stability of electrical properties with time, 2—poor reproducibility of electrical characteristics from melt to melt, 3—excessive temperature coefficients of resistance, and 4—excessive cost. Weston introduced the Cu-Mn-Fe and Cu-Mn-Ni-Fe alloys of the type now generally known as manganins. His patents are believed to represent the first disclosure of any alloy with a negative temperature coefficient of resistance. After this work, the German company, Isabellenhutte, in conjunction with Feussner and St. Lindeck, produced alloys of

Jan 1, 1957

By Robert S. Young

During the last quarter-century, exploration for metallic deposits in Maine has been sporadic with peaks generally coinciding with periods of high metal prices. Known cases of regional or semi-regional evaluations are few; most efforts have been local and usually intensive. On the basis of broad geologic groups, the State has been divided into five fundamental environments: ( 1) coastal metamorphic belt; (2) southern volcanic belt; (3) Silurian slate belt; ( 4) northern volcanic belt; and ( 5) Devonian slate belt. Although not restricted to these areas, exploration in recent years has been concentrated in the northern and southern volcanic belts. Notable examples of recent exploration activity, directed to sulfide minerals, include: ( 1) the Knox County nickel-copper-bearing ultramafic rocks; (2) the Harborside (Cape Rosier) copper-zinc deposit; (3) the Second Pond (Black Hawk) zinc-copper-lead-silver deposit; ( 4) the Big Hill-Barrett lead-zincsilver- copper-gold zones; (5) the Parmachenee copper-zinc belt; ( 6) the Moxie Lake nickeliferous peridotite; and (7) the Attean quartzmonzonite molybdenum-copper occurrences. The Second Pond and Harborside prospects appear to be close to production. Systematic investigations for non-metallic deposits appear to have been aimed principally toward limestone, asbestos, diatomaceous earth, and spodumene-bearing pegmatites. Advances in prospecting methods, high metal prices, a favorable business outlook, increasing cooperation from large landholders, and some discoveries support the probability of increased exploration activity in Maine during the coming decade.

Jan 1, 1968

By K. Brack, G. H. Schwuttke

Annealing properties of subszerface amorphous lavers produced through high-energy ion implantation in silicon are studied. The buried layers are produced through the implantation of ions (nitrogen), ranging in energy from 1.5 to 2 mev. X-ray interference patterns, transmission electron microscopy, and resistivity profiling are used to study the annealing characteristics of the ion damage. The annealing experiments indicate a low temperature (below 700°C) and a high temperature (above 700°C) region. Significant changes occur in the amorphous layer during the high-temperature anneal. Such changes are corre-lated with the re crystallization of the amorphous silicon and the formation of subsurface (buried) silicon-nitride films. TODAY&apos;S main problems in the field of ion implantation are related to the accurate determination and prediction of 1) the distribution profiles of implanted ions, 2) the lattice sites occupied by the implanted ions, 3) the lattice damage produced through ion implantation, and 4) the annealing characteristics of damage centers in the lattice. This paper reports investigations concerned with the problems listed under 3) and 4). EXPERIMENTAL Our investigations cover the energy range of incident ions from 100 to 300 mev and from 1 to 2.5 mev. The emphasis of this study is on the energy range from 1.5 to 2 mev. The experiments are conducted with single charged nitrogen ions. To implant the ions a van de Graaff generator is used as described by Roosild et al.1 Accordingly, a gas containing the desired ion specie is passed through a thermome-chanical leak into a radio frequency activated source. The positive ions are driven into the van de Graaff with the help of a variable voltage probe. Emerging from the accelerator the ions drift into a magnetic analyzing system and here the desired ion specie is bent 90 deg into the exit port. The ion beam leaving the analyzer is defocused and drifts down a 4-ft long tube to hit the silicon target. At this position the 20 pamp ion beam has a circular cross-section of 2.1 cm. N2 is used as a source gas for nitrogen ions. The implantation target is silicon with zero dislocation density, 2 ohm-cm resistivity, (111) orientation, mechanically-chemically polished, and 1 mm thick. The target is mounted on a water-cooled heat sink and kept at room temperature. A fluence of 1015 to 1016 ions per sq cm is used. RESULTS 1) Silicon Perfection after Bombardment. High-energy ion bombardment of silicon has some striking effects on lattice perfection. Some results were reported in detail previously at the Santa Fe conference2 and are here briefly summarized for the benefit of the experiments described in the following. 1.1) Identification of Surface Films on Silicon. After bombardment all samples are found to be coated with surface films. The films on the silicon surface vary in thickness and color; they can be transparent, slightly brown, or opaque. The films are thicker and darker in the high-intensity area of the beam and they delineate the bombarded surface area of the crystal. The films produce electron diffraction patterns characteristic of carbon and of SiO2. Carbon is predominant. The presence of carbon in these films was confirmed by use of the electron microprobe. Formation of the films occurs independently of the ions used and is attributed to a contaminated vacuum of the high-voltage machine. The carbon is most likely the product of the pump oil which is cracked and polymerized under ion impact. The films stick tenaciously to the silicon surface and burn off in a low-temperature Bunsen flame. 1.2) Mechanical Perfection of the Silicon Surface. The mechanical perfection of the bombarded silicon surface was investigated through optical microscopy, electron microscopy in which the replica technique is used, and optical interferometry. No mechanical damage of the surface was visible after bombardment. However, if a bombarded sample is soaked for several minutes in hydrofluoric acid (HF), gas bubbles may develop in certain spots of the silicon surface. It is also noted that in these areas the surface film starts to peel off. Relatively large patches of film come off if the sample is soaked in HF during ultrasonic agitation. After HF treatment, pits may be present on the silicon surface. The pit dimensions are estimated to be as large as 50 µ. The pits appear in the region of most intense irradiation. 1.3) Lattice Perfection After Bombardment. No lattice damage is found on the silicon surface. Electron transmission micrographs and selected area diffraction patterns of the surface show no difference before and after bombardment. Measured approximately 2 µm down from the surface, the silicon lattice throughout this depth is of good perfection. Well-defined Laue spots and Kikuchi lines are obtained from the surface as well as from the indicated area below the surface. However, some radiation damage is dispersed in this top layer. A sharp boundary line separates this surface layer from a highly damaged layer which extends further downward into the silicon. Typical of this

Jan 1, 1970

Jan 1, 1920

By H. H. Richardson, E. H. Dix

Of all the alloying elements used in commercial aluminum alloys, copper stands out as by far the most important, and it is perhaps for this reason that the constitution of the aluminum-copper system has received the attention of a number of experimenters covering a period of approximately 20 years. It would be expected that during this time the equilibrium relations would have been thoroughly and exactly worked out. In a general way this is true, but there is a surprising lack of agreement in the details of the high aluminum end of the diagram, particularly in regard to the solid solubility of copper in aluminum, which has been given variously as 2 per cent. to 5 per cent. at the eutectic temperature. The importance of this is much greater than might at first appear to one unfamiliar with modern commercial aluminum alloys. This is true because, with one exception, the susceptibility of the strong alloys to heat treatment depends, in part at least, upon the solid solubility relations of copper in aluminum. In 1919, Merica, Waltenberg, and Freeman1 published the first detailed information on these solubility relations. They found that the solubility of copper decreases with falling temperature from about 4 per cent. at 525" C. to about 1 per cent. at 300" C. and is apparently still diminishing at lower temperatures. In 1921 there was published a brief account of the results obtained in the National Physical Laboratory, Teddington, England.2 This laboratory, however, reported that 5 per cent. of copper is soluble in aluminum at 540" C., and that this amount decreases to about 3 per cent. at 20" C. In the same year Ohtani and Hemmi3 reported a solubility of 4.8 per cent. copper at 520" C., 2.6 per cent. at 460" C. and 1.5 per cent. at 420" C.

Jan 1, 1926

By R. E. Whippo, B. L. Murowchick

The commercially exploited sedimentary apatites exhibit a number of variable lattice substitutions which affect their chemical composition. Carbonate is a major diluent of phosphorus values in sedimentary apatites. Substantial amounts of water as hydroxyl, hydronium, and tetrahedral hydroxyl ions substitute for fluorine and oxygen, calcium, and phosphate, respectively. Calcium is also replaced by several other divalent and monovalent cations. The structural formula demonstrates the substitutions in the lattice of the sedimentary apatites studied in view of the crystal-chemical relationships which have been postulated for the isomorphous apatite series. The lattice constant a. varies from 9.29 to 9.40 A for the apatites studied. Quantitative relationships between this constant and lattice substitution are complicated by the interaction of multiple substitutions whose influence is non-additive. The mineral apatite, the principal raw material source of phosphorus for agricultural and industrial applications, offers a wide area for investigation. Considerable research effort has been expended in the study of apatite crystal-chemistry by medical, biological, and earth scientists. Few of these studies deal directly with the sedimentary apatites from the major occurrences which are widely exploited for commercial uses. It is the purpose here to present chemical analyses of several sedimentary apatites and discuss their chemical composition in relation to the structural and crystalchemical principles which have been postulated for the apatite isomorphous series. THE STRUCTURE OF FLUORAPATITE The atomic structure of fluorapatite was described, independently, by Ngray-Szabd and Mehmel in 1930 and has been accepted as presented, with only minor changes,4 since that time. The hexaogonal unit cell with dimensions of a = 9.37 0.01 A and c = 6.88 0.01 A contains two molecules of the composition "There are six (PO4) groups in the cell, four calcium ions on the trigonal axes, surrounded prismati-cally by six oxygen ions and six calcium ions surrounded by an irregular polyhedron of a fluorine and five oxygens. Fluorines are at the comers of the reflexion planes, touching three calcium ions each".l7

Jan 1, 1968

By R. Taggart, R. H. Ericksen, D. H. Polonis

MarTENSITIC a has been observed to form spontaneously from the retained ß phase during the preparation of thin foil specimens of metastable Ti-Cr alloys containing from 6.9 to 20 wt pet Cr. Similar spontaneous martensite reactions have been reported in thin foils of 0 brass&apos; and other alloys.2 4 The absence of retained austenite in iron-based alloys has also been attributed to spontaneous decomposition during thinning.5 The present work indicates that a unique situation occurs during which the spontaneous transformation takes place when the transitional ? phase is present in the as-quenched or partially aged ß phase. Alloys containing 6.9, 7.0, 8.0, 12.0, and 20.0 wt pet Cr were prepared by the levitation melting of "io-chrome" chromium and iodide titanium. The 0.5-in.-diam ingots were vacuum-annealed at 1000oC, and wafers 0.020 in. thick were then cut from the ingots. These wafers were wrapped in molybdenum foil, encapsulated in Vycor under a reduced pressure of purified helium, and then held for 30 min at 1000°C. The specimens were quenched in water to retain the metastable high-temperature ß phase. The quenched alloys were thinned by mechanical grinding to about 0.005 in. thick, then electropolished in a solution of 300 ml methyl alcohol, 175 ml n-butyl alcohol, and 30 ml perchloric acid at a temperature of -40°C. Needle specimens 0.005 to 0.010 in. diam were taken from each ingot and heat-treated with the foil specimens. X-ray diffraction patterns indicated the structure of the 6.9, 7.0, and 8 wt pet alloys to be a

Jan 1, 1968

By AIME AIME

THE American Institute of Mining and Metallurgical Engineers will hold its annual meeting in New York City, Feb. 9-12. The technical sessions, excepting the Sunday afternoon and evening sessions of the Mineral Industry Education Division (see the M.I.E.D. program) will be held in the Engineering Societies Building. The "All-Institute" luncheon on Monday will be at the Commodore Hotel; the Annual Banquet and President&apos;s Reception, the Smoker, and the Informal Dance will be at the Waldorf Astoria Hotel. The dinners of the Petroleum Division and the Institute of Metals Division will be at the Roosevelt Hotel.

Jan 1, 1942

By A. B. Kinzel

SILICON and its metallurgical uses have been the subject of speculation since the earliest days of modern civilization. The early philosophers, Theophrastus and Pliny, believed that silica was a special form of ice, an opinion that was not seriously challenged until the seventeenth century. The first comprehensive view of the nature of silica was advanced by Lavoisier in 1787. He assumed silica to be an oxide of an unknown metal. In 1808 Berzelius produced ferrosilicon by heating silica, iron and charcoal. Probably the first produc¬tion of crystallized silicon was in 1854 when H. St. C. Deville accidentally produced the material while electrolyzing a double chloride of aluminum and sodium containing siliceous impurities. It is not strange that the early investigators should have given so much attention to silica and silicon, because of the great natural abundance of the former. Although silicon does not exist in the elemental state in nature, it has been estimated that the lithosphere contains approximately 60 per cent silica; quartz and rock crystal are found in practically every part of the world.

Jan 1, 1933

By C. C. Harris

An analytical solution of the integro-differential equation of batch grinding is proposed as a first appoximation to the xYt surface. The size distribution equation (xY plane) is a three parameter equation previously suggested. Possible refinements are outlined. Comminution kinetics research is presently following several related courses. Some are equivalent, in that they represent different ways of viewing the same facet of the problem, though the entire endeavor cannot be described as being completely integrated. The purpose of this note is to propose and discuss a framework into which the various approaches might be fitted. This must clearly be founded upon an analysis of the xYt surface.&apos; (See also Fig. 1 of Reference 26.) The investigations referred to above comprise mainly researches into the following: (1) The kinetics of the creation of the finer sizes during relatively small grinding times. This is the Fahrenwald-Arbiter-Bhrany 2-3 approach which leads to equations equivalent to a special case of the charles4 relationship. It emerges that initial production of fines follow essentially zero order* kinetics. (2) Disappearance kinetics of the coarser fractions. This appears to be a first order relationship.5-6 (3) Prediction of the xYt surface via the selection and breakage functions utilizing computer-programmed or approximate solutions of the integro-differential equation of batch grinding.5,8-17 A recent discussion by Mika et al.5 references the relevant literature up to about 1966. In addition to these main-stream researches there is some work on the minor topic of extremely long grinding time considered as a limiting case.18-19 The field is supported by investigations into the size distribution of fragments produced by breakage processes, some of this work being most valuably statistical-mechanical in nature.20-25 Better fitting equations, however, are obtained by statistical and curve-fitting methods.26 This

Jan 1, 1969

By Murray F. Hawkins, Marion L. Kimmel

sage&apos; appears to have been the first (1933) to design a rolling ball viscosimeter for the express purpose of measuring the viscosity of oils with natural gas in solution, i.e., under reservoir conditions. In 1940 Hocott and Buckley&apos; further refined the rolling ball instrument in both design and method of operation, and their instrument, known as the Humble type, was the forerunner of present day viscosimeters used in petroleum production and research laboratories. They also initiated the technique of charging the viscosimeter with a sample directly from a bottom hole sampler. In 1948 the committee on engineering research 01 the Petroleum Division of the AIME in Part 3 (1) of

Jan 1, 1955

By Lo-Ching Chang, K. M. Goldman

The kinetics and mechanism of transfer of a constituent across a slag-metal interface are fundamentally important because many metallurgical processes involve the existence of a slag phase and a metal phase. Industrial processes seldom proceed to equilibrium, and information of the rates and modes of reactions are therefore often of greater practical importance than equilibrium data. A study of the kinetics of sulphur transfer across a slag-metal interface under reducing conditions will contribute a great deal toward a better understanding of desulphurization in the blast furnace process. The general principles existing in the transfer of a constituent, such as sulphur, across a slag-metal interface can be extended to similar transfer phenomena in other metallurgical processes. The present paper will demonstrate how such studies will lead to fruitful results from both the practical and theoretical standpoints. EXPERIMENTAL METHOD The apparatus used was, simple. A graphite crucible 15/8-in. id, a wall 1/8-in. thick, and a depth of 4 in., was packed in an outer fused silica tube with powdered magnesia. The crucible assembly was rotated at a speed of 235 rpm inside an in- duction coil. A charge of 250 g of Armco ingot iron was introduced into the graphite crucible and melted by induction heating. The melt was held at a desired temperature for 3-5 "&apos;in., aftcr which 7.5 g of granular ferrous sulphide was added and the bath was held for another 3-5 mi11. A metal sample was then taken by means of a fused silica tube and a rubber suction bulb. Immediately after the metal sample was taken, 30 g of a prefused and crushed slag were introduced. The slag reached the ternperature of the furnace in 1 to 1 1/2 min. Slag

Jan 1, 1949

By K. M. Goldman, Lo-Ching Chang

The kinetics and mechanism of transfer of a constituent across a slag-metal interface are fundamentally important because many metallurgical processes involve the existence of a slag phase and a metal phase. Industrial processes seldom proceed to equilibrium, and information of the rates and modes of reactions are therefore often of greater practical importance than equilibrium data. A study of the kinetics of sulphur transfer across a slag-metal interface under reducing conditions will contribute a great deal toward a better understanding of desulphurization in the blast furnace process. The general principles existing in the transfer of a constituent, such as sulphur, across a slag-metal interface can be extended to similar transfer phenomena in other metallurgical processes. The present paper will demonstrate how such studies will lead to fruitful results from both the practical and theoretical standpoints. EXPERIMENTAL METHOD The apparatus used was, simple. A graphite crucible 15/8-in. id, a wall 1/8-in. thick, and a depth of 4 in., was packed in an outer fused silica tube with powdered magnesia. The crucible assembly was rotated at a speed of 235 rpm inside an in- duction coil. A charge of 250 g of Armco ingot iron was introduced into the graphite crucible and melted by induction heating. The melt was held at a desired temperature for 3-5 "&apos;in., aftcr which 7.5 g of granular ferrous sulphide was added and the bath was held for another 3-5 mi11. A metal sample was then taken by means of a fused silica tube and a rubber suction bulb. Immediately after the metal sample was taken, 30 g of a prefused and crushed slag were introduced. The slag reached the ternperature of the furnace in 1 to 1 1/2 min. Slag

Jan 1, 1949

By H. M. Woodroffe, H. K. Conn, S. J. Rice

World production of asbestos is estimated to be at a current level of almost 3.5 million tons, having more than doubled in the past ten years. A substantial part of the increase has been due to a rapid expansion in the Soviet Union. Production from that country during 1964 is estimated at 1.5 million tons and, as a consequence, Russia has displaced Canada as the leading world producer. Although traditionally the asbestos mining industry has been centered near Sverdlovsk in the Urals, two new producing areas have been under development for some time. It is expected that a new mine will be in operation in 1965 near Kiembi, Kazakhstan, some 300 miles south of Sverdlovsk, and an- other mine at Aktrovak in Tannu-Tuva, west of Lake Baikal. These developments will provide a significant increase in the production capability of Russia. Although internal consumption is expected to increase with the addition of new asbestos- cement producing facilities now under construction in Russia, there is some speculation that exports will also increase.

Jan 2, 1965

By C. D. King

A QUARTER century ago this country was producing an extraordinary quantity of iron and steel, with a decisive influence on the outcome of the first World War. Today this country is again demonstrating its industrial capacity with telling results. If this lapse of time has confirmed the opinion that man learns little from experience with respect to human relationships, at least we can derive some consolation from the knowledge that in the same period we have made huge strides industrially, and particularly in the steel industry. The differences represented by 25 years are striking, and have resulted from a multitude of changes that have contributed to the present-day high state of our pig iron and steel manufacture.

Jan 1, 1944