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The nickel suppliers are hard at work across the entire spectrum of the industry-from exploration and mining on the one hand to the development of new applications of this unique metal on the other. The reason-a surging demand for nickel by the free world. Evidence of interest and activity in nickel abounds. Companies such as Anaconda, American Metal Climax, Kaiser Aluminum & Chemical, Patino, Newmont-firms that have not been in the nickel industry before-are now involved in various exploration and development ventures around the world. International Nickel, Falconbridge, Le Nickel and Sherritt Gordon-the big names in the industry -have committed vast sums of money and talent in a variety of new developments designed to ensure their status as leading producers of this commodity. As a result, the world is now seeing a rapid build- up in nickel capacity, and in this issue of [ ], the editors have prepared a summary of these fast- moving major developments.

Jan 10, 1968

By Herbert H. Uhlig

A STUDY of passivity in chromium-iron alloys holds considerable interest, both because of the present-day practical importance of the stainless steels, and because of the scientific importance attached to the mechanism of their corrosion resistance. Upon the discovery of the passive chromium-iron alloys in 1912, it seemed logical to attribute the observed phenomenal corrosion resistance to a thin, continuous, protective reaction product on the surface. The product was thought to be Cr2O3 or a similar oxide containing both chromium and iron. This mechanism seemed likely in view of Michael Faraday's conjecture that passive iron is not reactive in concentrated nitric acid because of an oxide on the metal surface.† Since 1912, data have accumulated that permit a further exploration into the nature of passivity and provide a new approach to the problem. A summary of the facts lends considerable weight to a mechanism based not on physical protection of an oxide or similar compound, although such compounds may be present on the surface, but to a change in tendency of surface metal atoms to react chemically. This change in reaction tendency is ascribed to chemisorbed films that effectively satisfy residual valence forces of the metal surface, but do not appreciably disturb the positions of metal atoms in the lattice. In other words, formation of a new lattice such as that of an oxide is not a necessary condition for this type of passivity. The decreased reaction tendency of the metal by reason of chemisorbed films can thereby account for low reaction rates of the stainless steels in many media, as well as a noble galvanic potential as is observed. Substances capable of adsorbing on the stainless steels, and hence accompanying the property of passivity, are typically oxygen, nitrites or chromates, but are not in any sense limited to these. Other elements and compounds can also chemisorb, and therefore may also play a major part in the mechanism of passivity in specific media. The mechanism of passivity based on chemisorption or activated adsorption begins with the interpretation Langmuir proposed for his experiments concerning adsorbed oxygen on tungsten.1 He found that adsorbed oxygen was tightly bound, remaining on the tungsten surface above temperatures at which WO3 rapidly volatilizes. The oxygen in such a state did not readily react with hydrogen even at

Jan 1, 1947

By B. B. Zavoico

The oil industry in the Soviet Union closed the 1929-1930 operating year fulfilling its assigned program. During this period of time, however, no basic improvements were noted within the industry. A careful study of the conditions indicates that disorganization in most branches increased continually; that supply and transportation problems are approaching a state of breakdown; that labor problems become increasingly difficult and that the estimates for 1931-1933 period are too large. The production of all Russian fields increased by 27,200,000 bbl., as compared with the 1928-1929 operating year, while the next year's program anticipates a further increase of 46,000,000 bbl., and the 1933 plans call for an amazing total of 330,000,000 bbl., or over 150 per cent, more than the production of the operating year that has just closed. Table 1 shows petroleum production in Russia by individual areas and fields from 1916, and furnishes estimates for the three coming years, which constitute the balance of the Five-year plan. A brief analysis of Table 1 will show that the Soviet Planning Commission anticipates that the fully developed fields of the Apsheron-Baku will double their production by 1933, .as compared with 1929-1930, and that the old Grozny fields, which are already showing a tendency to decline, will increase their output from 44,110,000 bbl. in 1929-1930 to 68,000,000 bbl. in 1933. Furthermore, in 1933 new fields are slated to produce not less than 100,000,000 bbl., a figure which even under most favorable conditions in Russia would be hard to achieve. Of course, Russia could develop such production, because the country is not lacking in the prospective reserves, but the transportation in the country today (as in the past.) is in such poor shape that neither the supply of a gigantic oil industry nor the movement of its products is within the realm of possibility. Table 1 shows the future estimated crude oil production as required by the Five-year plan, and also as reasonably estimated by the author, taking into account natural declines in old fields, slow development of new areas and the deficiency of the transport. While in the 1929-1930 operating year only two major fields underproduced (Surakany and Maikop) and the plan was fulfilled to the extent of 97.4 per cent., the production of the last three months of 1930 ("Shock Quarter") indicated

Jan 1, 1931

By C. O. Burgess, A. B. Kinzel

Although vanadium is an important constituent of almost every brand of high-speed steel manufactured today, little is known as to its role in this series of alloys. The now standard 18 per cent tungsten and 4 per cent chromium constituents were the result of developments and improvements before 1903. In that year, vanadium was added to the steel by Dr. J. A. Mathews. This proved to be an outstanding contribution, so that the standard high-speed steel of today is generally referred to as the 18-4-1 type—18 per cent W, 4 per cent Cr and 1 per cent V. Various modifications have been attempted since then, but with the exception of the introduction of cobalt, no striking improvements have occurred. Vanadium has been increased to 2 per cent in many of the common brands, and at least one brand contains 5 per cent V in addition to the usual tungsten and chromium. The carbon has been gradually increased so that it is not uncommon to find 0.80 per cent in the standard grade, although the carbon in the 5 per cent vanadium steel mentioned above is approximately 1 per cent, and even 1.2 per cent has been made experimentally. The role of vanadium has never been well understood, and although vanadium has been increased to 2.5 and even 5 per cent in certain high speed steels, it has not been generally established that the higher vanadium contents result in superior cutting properties. However, in all of the investigations, of which the writers are aware, the interrelation of the vanadium and carbon contents was not considered as a prime factor. The carbon content was held at 1.2 per cent or less—generally at the usual 0.65 to 0.75 per cent. Theoretical Aspects Although the role of vanadium is not understood, there are theoretical considerations which indicate definite reasons for the improved cutting effciency due to vanadium. Refinement of the secondary grain is one distinct possibility. The well-known action of vanadium in limiting grain size might well be expected to operate in high-speed steels, and even though its action were not evident in the parent austenite grain.

Jan 1, 1932

By J. B. Newkirk, D. L. Martin, A. H. Geisler, R. Smoluchowski

A FUNDAMENTAL investigation of the mecha-nism of the ordering reaction and of the accompanying changes in properties has been undertaken, since an extensive study of this process could well contribute to the knowledge of phase transitions in alloys. Cobalt-platinum alloys were chosen for the study since they exhibit interesting and unusual permanent magnet properties.1,2. In addition, the ordering reaction in cobalt-platinum alloys is a convenient one to study experimentally because of the high maximum ordering temperature, the large difference in the X-ray scattering power of cobalt and platinum atoms, and the relative ease with which the alloys can be plastically worked into wire and strip. In the early stages of this study, it became apparent that the published phase diagrams&apos;, &apos; of the cobalt-platinum system contained questionable features, in the region of 40 to 60 atomic pct Co, which were considered in another publication by the authors.4 That portion of the research reported elsewhere on the equilibrium states of cobalt-platinum alloys does not confirm the presence of a previously reported, high temperature disordered tetragonal phase and a low temperature body-centered cubic phase. On the other hand, the structure of the ordered phase is face-centered tetragonal with an atomic distribution analogous to that of CuAu.4 This lattice forms from the disordered face-centered cubic phase in such an orientation that the <100> directions are parallel to the <100> direc-tions of the disordered phase. At compositions other than the ideal 50 atomic pct the ordered phase can exist in equilibrium at high temperatures with the disordered phase. A Widmanstatten pattern of plate-like particles of the ordered phase parallel to (110) planes of the disordered matrix is observed when an initially disordered alloy is held at these temperatures. The temperature range of the two-phase region has been determined for three alloys by X-ray diffraction analyses, microscopic examination, and electrical resistivity measurements, and these results are incorporated with some of those of Gebhardt and Köster in the revised phase diagram of fig. 1. The purpose of the investigation reported here was to examine the mechanism of ordering in co-balt-platinum alloys by X-ray diffraction and metal-

Jan 1, 1951

By John Griffen

The modern anthracite breaker or washery uses almost exclusively a wet method of preparation, which requires, roughly, 1 gal. of water per minute per ton of production per day. The entire anthracite industry uses about 320,000 gal. per min. of water for this purpose or 800,000 tons of water per day. As this water leaves the breakers, it contains fine solids—coal, slate, pyrite, and clay—and is then called silt or slush; as slush is the term most commonly used, it will be employed throughout this paper. The solid content of the slush will be referred to as solids. In the earlier days of anthracite mining, little coal was washed, less crushing was employed, and virgin coal was mined exclusively. As a result, the slush problem was not acute because of the relatively small quantity and the coarseness of the solids. Such slush as was produced could usually be easily impounded and retained or could be discharged into streams without any appreciable pollution being apparent. The character of the fine waste from the breakers changed materially as its quantity increased until now about 40,000 tons of slush solids are produced daily. Second mining and robbing operations materially increased the quantity of fine solids delivered to the breaker in the mine car. The demand for chestnut, stove and egg sizes, to the exclusion of grate, steamboat, and lump sizes, requires finer crushing of the mine-run coal with a consequent increase of fine solids in slush. The use of rice and barley sizes removed a considerable tonnage of coarser solids from the slush but left great quantities of fine solids difficult to retain completely, and to store, and long considered of no possible fuel value. Despite the efforts of the coal operators, the slush solids have found their way into the streams causing, in some cases, serious pollution. The Water Supply Commission of Pennsylvania published, in 1916, a report on Culm in the Streams of the Anthracite Region,&apos; from which the following is taken: About 40,000,000,000 gal. of water carrying 10,000,000 tons of fine culm are discharged into the water-courses direct, flushed into the mines, or disposed of by various means on the surface. The extent to which the very small sizes of anthracite have been deposited in the rivers draining the coal fields is made evident by the fact that over a quarter of a million tons are recovered annually from the river beds by coal-washing operations.

Jan 1, 1922

By H. William Ahrenholz

Many technical meetings were attended by mining people during the past year in which rock mechanics was either the main subject for discussion or was a prominent part of the program. Several universities continued to offer short courses in the applications of rock mechanics for practicing mining engineers. At the beginning of the year, the AIME Committee on Rock Mechanics achieved standing-committee status. It is to assume responsibility for coordinating all AIME activities in this area. Eleven professional societies are now participating in a newly formed Intersociety Committee for Rock Mechanics. AIME and its constituent societies has three representatives. Delegates from the Intersociety Committee will serve on the U.S. National Committee for Rock Mechanics which is being formed by the national Academy of Sciences.

Jan 2, 1967

By B. W. Frazer

In the numbers of the Engineering and Mining Journal of June 27th and July llth, 1874, there appeared some very complete statistics of the working of some anthracite blast-furnaces belonging to a large establishment in this country, followed by calculations of the heat requirements of the furnaces, similar to those which have been made for European furnaces by Mr. I. Lowthian Bell, Prof. Gruner, Prof. Akerman and others. To the author of these valuable papers, Mr. John A. Church, of New York, the thanks of American iron metallurgists are due for this attempt (the first, to my knowledge at least), to attack systematically and scientifically the problem of economy of fuel in our anthracite blast-furnaces, by applying the formulas obtained from European practice and from the experiments of European metallurgists, to the determination of the amounts and the modes of distribution of the heat production and absorption in our furnaces. In order to facilitate a comparison of the results thus obtained for the anthracite furnaces in question with those obtained for the best types of European coke furnaces, I have reduced 60 the same standad of heat units (the product of the ton and the degree Centigrade), and placed side by side, the calculations of the heat requirements of one of the furnaces of the Clarence works, as given by Mr. Bell, of a furnace at Pouzin, on the banks of the Rhone, given by Prof. Gruner, and of the anthracite furnaces for 1869-73, as given by Mr. Church. Table I shows the different conditions of working of the three furnaces, of which Table II gives the respective heat requirements. I have made this latter table in such a manner as to give for each furnace its heat requirements, both according to the views of Mr. Bell and those of Prof. Gruner. Mr. Bell assumes that all the carbonic acid produced by the decomposition of the carbonate of lime of the charge, is reduced to carbonic oxide by contact with solid carbon ; also, that the carbon of t,he pig iron is a portion of that deposited in the ore in the upper part of the furnace, by the dissociation of carbonic oxide. Prof. Gruner, on the other hand, assumes that all the carbonic acid of the carbonates of the charge escapes unreduced, and that the carbon deposited in the upper part. of the furnace, by the dissociation of carbonic oxide, is again converted into carbonic oxide or

By R. E. Rowlands, I. M. Daniel

An experimental study is discussed of the state of strain, deformation and fracture around lined and unlined cylindrical cavities in rock under biaxial compressive static loading. The specimens were limestone plates 36 in. high, 24 in. wide and 3 in. thick with a 4 in. diameter hole unlined or lined with hydrostone and aluminum liners. The ratio of horizontal to vertical applied stress was one-third. Experimental techniques used were strain gages, differential transformers and photoelastic coatings. Strain distributions were plotted along the horizontal axis of symmetry for various levels of applied stress. The agreement with theory was good at low stress levels but appreciable deviations occurred at higher levels and near the hole. The experimental strain concentration factor was nearly the same, slightly higher and appreciably higher than the theoretical value for the hydrostone-lined, unlined and aluminum-lined specimens, respectively. Failure modes were splitting along a vertical plane for the unlined and hydrostone-fined specimens, compressive (shear) failure for one unlined specimen and splitting with radial cracking for the aluminum-lined specimen. In the latter, a maximum tensile stress of more than three times the uniaxial tensile strength existed at the interface with the liner at the time of fracture,

Jan 1, 1971

By P. W. Bakarian, C. H. Mathewson

THE greater part of the literature on the plastic behavior of magnesium dates back to that active period of research in crystal mechanics immediately following the widespread preparation of isolated metallic crystals large enough for the application of conventional methods of mechanical testing. These investigations, performed on single crystals, revealed an analogy between zinc and magnesium with respect to their fundamental mode of deformation, in the operation of glide and twinning, respectively, on crystallographically similar planes. Mathewson and Phillips (1928)1 by geometrical analysis identified the {102} ? plane in magnesium as the twinning plane, Schiebold and Siebel (1931)2 confirmed this twinning plane, established the basal plane as the plane of slip, and a digonal axis I as the slip direction. They also reported twin formation in a secondary role on the {101} plane. Schmid (1931)3 summarized and discussed the earlier evidence and presented the results of his own experiments on the effect of temperature and small amounts of soluble elements. From X-ray studies on extended wire single crystals, he concluded that slip along the basal plane in the direction of the digonal axis I closest to the stress direction was the sole slip system operating at atmospheric temperature. This conclusion was based on experiments with crystals of many different orientations relative to the stress axis. Special attention was directed to the basal plane and the digonal axis I, as the plane and direction of greatest atomic density. Determinations of resolved shear stress at the onset of plastic yielding-i.e., the critical resolved shear stress-were also made; the average of these calculations showing 82.9 grams per sq. mm. This value varied only slightly up to 300°C., at which temperature it was found to decrease to 70.5 grams per sq. mm. The extension of his crystals at temperatures above 225°C. further disclosed the presence of new slip systems. After the original specimens of circular section had been

Jan 1, 1943

By R. P. Rothwell

THE milling of silver ores has arrived at a great degree of perfection in the mining districts of our Western States and Territories, and I have thought the record of the practical results obtained at the present time, in a few of the principal districts, would prove of value and interest to many of our members, both at home and abroad. An American silver mill is composed, in descending order from where the ore is dumped, of: 1st. A rock-breaker, usually of the Blake or Alden pattern ; 2d. The battery of stamps, the number of which varies from 5 to 120, generally in batteries of 5 or 10 heads, so arranged that a single battery may stand while the others are running; 3d. The tanks where the crushed ore settles (if it is a wet stamping-mill), or of a drying-floor if the crushing is done dry; 4th. Amalgamating pans ; 5th. Settling pans ; 6th. Agitators or pans in which mercury escaping in the tailings is caught; 7th. Blanket sluices, over which the tailings run, and where mercury and unamalgamated sulphides are saved. A reference to the engravings (see plate), which show one of the latest forms of an 80-stamp silver-mill run by a turbine water-wheel, will show clearly the arrangement of the several parts. THE ONTARIO, UTAH, SILVER MILL. One of the best examples of a silver-mill, and at the same time one of the most successful concerns in the West, is the mill of the Ontario Silver Mining Company, near Salt Lake, in Utah. This mill treats the ore from the Ontario mine, ore which at present is very base, being composed of zinc, lead, and silver sulphides and silver chloride in a quartz gangue. This ore has become baser as the mine attained greater depth, though the vein holds its own, or rather increases, both in thickness and richness. The mill is man¬aged in a skilful and economical manner, though the necessity for * Read at the Montreal meeting, September, 1879.

Jan 1, 1880

By W. G. Woolnough

It is perhaps a little difficult for Americans fully to appreciate the slow progress in the search for oil in Australia. Conditions are so different from those in the United States that methods must also differ considerably. Australia possesses an area almost exactly equal to that of the United States, but has a population of less than 7,000,000, and this population is concentrated almost entirely around the eastern and southern coasts of the continent. There are, therefore, vast "empty spaces" entirely unpopulated or exceedingly sparsely populated. The emptiness is due not to any lack of energy or initiative on the part of Australians but to the arid and waterless character of much of the country&apos;s interior. Throughout the greater part of the area that is comparable with the Mississippi drainage area of the United States, there is not a single flowing stream, and over most of it the rainfall is less than 7 in. a year. This hinders exploration and geological survey, and also isolates from potential markets many of the regions that otherwise might be considered worth prospecting. Also, Australia consists of six independent and sovereign states. With the establishment in 1901 of the Commonwealth of Australia, the states retained complete control of lands and mineral rights. Each state has its own petroleum legislation, and the absence of a central controlling authority has tended to confusion and to the introduction of many complications in oil prospecting. There are three major "territories," administered by the Federal Government; namely, the Northern Territory, enclosed between the northern parts of Queensland and Western Australia, within Australia itself, and the Territories of Papua and New Guinea in the island of New Guinea. Land and mineral legislation in these territories is not uniform. Furthermore, during the late twenties there occurred an orgy of company flotation and indiscriminate drilling, wQch resulted in the discovery of some definite indications of oil in three of the states and two of the territories, but which failed to develop any producing oil field in the common acceptation of the term. Much money was squandered,

Jan 1, 1938

By G. H. Rowe, A. N. Stroh, D. P. Gregory

The magnitude and variation with strain of the parameters activation volume, V*; activation energy, H; and frequency factor, A, in the Arrhenius equation for strain rate are determined for colunlbium single crystals and polycrgstals. Comparison of dislocation structures in deformed columbium crystals as determined by transmission electron microscopy with the rate IF deformation of a metal crystal is a thermally activated process, rate theory can be used as a powerful tool in the study of dislocation mechanisms. seeger1 develops the following expression for plastic deformation governed by a single thermally-activated theory results suggests thai formation of lattice vacancies at jogs in screw dislocations is responsible for thermally activated deformation of poly crystalline columbium. Single crystals appear to deform by a different mechanism. Work hardening in fully recrystallized fine grain columbium is found to result from simultaneous decrease in activation volume and in the number of mobile dislocations with increasing strain. Work hardening in recovered polycrystals is found to result from decrease in activation volume with strain only. dislocation mechanism. His equation for strain rate is where N is the number of mobile dislocations per unit volume held up at energy barriers, v is the frequency with which the dislocations "try" the energy barriers, b is the Burgers vector, a is the area a dislocation loop sweeps out after overcoming a barrier, V* is the activation volume which will be defined more completely later, and t* is the thermal component of stress equal to (Ta-Ti), where Ta is applied shear stress and Ti is internal stress of the dislocation network17&apos; given by

Jan 1, 1963

Scientific elite of the Minerals Beneficiation Div. assembled in Denver, Colo., September 17 to 20 to commemorate the 50th Anniversary of Froth Flotation in the United States of America. In his warm address of welcome at the opening luncheon, John W. Vanderwilt, President, Colorado School of Mines, recalled his experience in Bonanza which coincided with the early days of flotation. In those years the scientific and engineering aspects of the process which we know today were little understood and operating the flotation circuit was considered an "art." Luncheon Chairman H. L. McNeill caught the flavor of the old days in an anecdote which recalled the mill nightmares to many present with the agonized words, "Oh God, what&apos;s happened to the concentrate now!" It was an appropriate gesture when he called the names of some of the flotation greats for presentation to the assembly; and many an "artist" there was among them!

Jan 10, 1961

By H. H. Hausner, O. V. Roman, F. V. Lenel, G. S. Ansell

The radial shrinkage during sintering of cylindrical compacts and loose aggregates of copper powder was measured. It was found to be nonuni-form from top to bottom of the samples and to depend upon the method of supporting them. The non-uniformity is due to the effect of gravity forces during sintering. Since gravity has an effect in sintering without externally applied stresses, no sharp dividing line can be drawn between conventional sintering and hot pressing. RECENT investigations of the sintering behavior of compacts1 and of loose powder aggregates2 have indicated that forces, other than those arising from surface tension effects, may play a role in shrinkage. In compacts it was shown that residual stresses from the pressing operation influence shrinkage behavior. In loose powder aggregates gravity forces due to the weight of the powder affect the ratio of shrinkage in the vertical and the horizontal direction. The main effort in the work reported here was to show that gravity plays a role also in the sintering of compacts. A few additional experiments were made confirming the effect of gravity in the sintering of loose powder aggregates. EXPERIMENTAL PROCEDURE Compacts and loose powder aggregates were prepared from irregularly shaped, electrolytic copper powder. Prior to use the powders were reduced 30 min at 400°C in dry hydrogen to remove surface oxides. Then the -325 mesh size fraction was separated from the -100 + 325 mesh fraction. The compacts were pressed at a pressure of 10,000 psi from 50 g of powder in a hardened steel die, 1 in. in diam. The height of the compacts was 0.725 i 0.005 in. An effort was made to get as uniform a green density distribution in the compacts as possible. The walls of the die were lubricated with a suspension of 3 pct of zinc stearate in acetone and the compacts were pressed using double action by first pressing the powder at 1200 psi with the die barrel supported, then removing the sup- ports and pressing to final pressure of 10,000 psi with the die barrel floating. The pressure was maintained for 10 sec. The compacts were sintered at a temperature of 925°C, generally for 1 hr. In order to maintain uniform temperature they were sintered in boats made from cylindrical copper blocks. The blocks were 2 in. in diam, either 2 or 2 1/2 in. long and, split to form the body of the boat and a lid. The body of the boat contained a cavity 1 3/8 in. wide, 1 in. deep and either 2 1/8 or 1 3/8 in. long. The longer cavity accomodated two samples, the shorter one only one sample. The uniformity of temperature distribution within the boats was checked with thermocouples welded to the top and bottom of the samples. The maximum variation between top and bottom temperatures was i 1/2°C. The actual sintering temperature was held constant within ±2°C. In order to determine the effect of gravity forces, i.e., the weight of the compacts, upon shrinkage, they were supported in the following ways during sintering: a) Full Bottom Support. The compacts rested either on a flat alundum disk or on alundum powders. b) Partial Bottom Support. The compacts rested on a graphite cylinder, 0.3 in. in diam which formed a projection on a larger graphite disk. It is difficult to balance the compact on the small projection. To avoid having the compact tip, a small hole was drilled through the compact and through the graphite disk and its projection. The graphite disk was then suspended from the lid of the boat by a thin iron wire which passed through the holes in the disk and the compact. c) Top Support, first type. A hole 3/32 in. in diam was drilled diametrically through the green compact 3/16 in. from the top of the compact. The compact was sintered suspended from an alundum rod (thermocouple protection sleeve) inserted into the hole. d) Top Support, second type. A hole was drilled axially through the center of the compact. The upper part of the hole from the top surface of the compact one fourth of the way down was 1/16 in. in diam; the lower part of the hole from the bottom surface three fourth of the way up was 3/32 in. in diam. The compact was suspended from the lid of the boat by an iron wire passing through the upper part of the hole and then tied into a knot. The loose powder aggregates were made by filling l in. deep, l in. diam cylindrical graphite molds with -325 mesh powder. To achieve uniform density in all the loose powder aggregates, the powders were settled in the molds by placing the

Jan 1, 1963

By E. B. Ekren, F. C. Frischknecht

Recently released results of surveys employing the slingram and turam methods show the applicability of electrornagnetics in mapping new areas containing both oxidized and unoxidized iron in the Lake Superior region.

Jan 10, 1961

By Henry S. Washington

During the last twenty years or so the chemical investigation of rocks has made great advances, and it is now generally recognized that a knowledge of the chemical composition is as essential as that of the texture or mineral composition—if not more so—for the proper classification of rocks and study of their origin and relationships. Rock-analyses have vastly increased in number and, what is of greater importance, in quality. New and improved methods permit of greater accuracy than was possible in the early days, and the list of chemical constituents frequently determined has risen from the seven or eight of the greater part of the nineteenth century, to twenty or more. Indeed, rock-analyses with determinations of so many constituents are now commonly made by the chemists of the United States and Australia, while in Germany, Great Britain, France, and Italy the rarer constituents are determined more frequently than formerly. As a consequence of this modern, accurate work, it has been discovered that some elements which were formerly supposed to be rare are of wide-spread occurrence and are often present in considerable amount. The fact is further being developed that the elements tend to show certain relations of occurrence or abundance in connection with each other. This is a fact which is applicable to the rarer elements, and which also finds a broad geological and petrological expression in the recognition of petrographic provinces. We are beginning to obtain some definite, though as yet rudimentary, knowledge of the distribution of the elements among igneous rocks. Some of the results along these lines obtained by study of the vast accumulation of analytical data now available are well known to petrologists, while others do not seem to be so gener-

Jan 1, 1909

By Charles Bohdanowicz

The accompanying tables&apos; show that in 1936 production of crude oil in Poland decreased very slightly (Tables 1 and 5), by about 1 per cent, and that gas production increased by about 11 per cent. As in preceding years, drilling (Tables 1, 2 and 3) was devoted principally to extension of oil fields in the Jaslo district (fields 1, 5 and 7) and, in a lesser degree, of those in the Stanislaw6w district (field 27). Production of crude oil is being sustained in a large measure by the deepening of old wells; besides a total number of 183 new wells completed (Table 3) about 152 wells were deepened, and in a general way the results of deepening were better than those of new wells drilled. Reserves of "proved land" have not increased as far as crude oil is concerned, but a notable extension of gas fieldsZ was attained in Daszawa (field 25) and in the Roztoki area (field 5). In the sub-carpathian zone gas fields have been proved in the vicinity of Kalusz, Kos6wJ and in the northwestern sector of that zone, between Tarnow and Lezajsk. The gas horizons of Daszawa occur in the Upper Tortonian, those of Kos6w in the Lower Tortonian (Middle Miocene). Exploratory drilling has been performed near Kalusz, and has been commenced near Kos6w and in the Tarn6w area. The Kos6w gas approaches the "wet" type. A possible gas reserve with a volume of 4,000,000,000 cu. m. (141,000,-000,000 cu. ft.) has been calculated, for an area of about 5 sq. km. of the Daszawa field, on the basis of production obtained and of decreases in pressure and their distribution. The fields of Roztoki and Strachocina (No. 12) have not yet supplied sufficient data for a calculation of reserves, which might possibly be estimated at 2,000,000,000 cu, m. (70,000,-000,000 cu. ft.).

Jan 1, 1937

By C. G. Dunn, P. K. Koh

THE primary recrystallization texture in cold-rolled silicon iron, which is the matrix texture for developing the Goss texture or the cube-on-edge texture by secondary recrystallization at temperatures near 900°C,1-5,21 has not been adequately described. Thus from the present available information, it is not possible to explain satisfactorily both the grain-growth selectivity of the matrix and the often observed magnetic torque curve, which itself provides some information on the texture. Also lacking is information on the special annealing texture that develops in this material when the annealing temperature is 1200°C or higher and the rate of rise to temperature is extremely rapid. From the work of May and Turnbull5 and from unpublished work, it was known that isothermal annealing near 1200°C tends to reduce the extent of secondary recrystallization and that a much weaker cube-on-edge texture results if appreciable normal grain growth replaces secondary recrystallization. Koh and Dunn6,7 have obtained additional information on complex primary recrystallization textures from further studies made after normal grain growth. In these instances the initial textures were retained during normal grain growth. A similar result reasonably could be expected in the present study except for the presence of a grain growth ihibitor1-5,8,9.21 and its tendency to allow only a few grains to grow. However, any information on the orientations of grains in the special annealing texture, even if far from representative of the initial matrix texture, would provide useful information on the nature of the matrix texture. In the present texture study the method of Newkirk and Bruce,10 which is based on the methods of Geisler" and Schwartz, 12 is used to obtain a complete (110) pole figure of the primary recrystallization texture. The high-temperature annealing texture is determined simply from the orientations of a large number of selected grains. The kinetic nature of the process that produces the annealing texture is treated elsewhere13 and it is shown that a form of secondary recrystallization with a very high rate of nucleation occurs during rapid annealing at high temperatures. EXPERIMENTAL PROCEDURE Commercial 0.014-in. cold-rolled silicon iron strip (3.16 wt pct Si), prepared by two stages of cold rolling with an intermediate short anneal, was given a decarburizing 3-min anneal at 800°C. Me-tallographic studies indicated complete recrystallization. Short-time anneals at 900° C and at higher temperatures proved that secondary recrystallization had not begun at 800°C, in fact, the short additional anneals were still in the induction period of secondary recrystallization. A rapid rise to an annealing temperature of 1260°C (2300°F) was obtained in a BaC12and NaCl fused salt bath. The structures that resulted from anneals in the range 12- to 1000-sec duration were relatively finegrained, even though the growth was a form of exaggerated grain growth13 or secondary recrystallization with a high nucleation frequency.= Many of the grains were large enough for an X-ray study using a 5-mil X-ray beam. A transmission Laue Camera and an optical-mechanical stage for moving the grains into the X-ray beam were used. A total of 325 grains were X-rayed in this manner and the grain orientations determined. Complete (110) pole figures were obtained for the primary recrystallization texture using CoKa radiation at 30 kv in the back-reflection range, such as (220) for (110) poles, as described recently by Newkirk and Bruce.10 The low voltage serves to reduce the spurious white radiation to a minimum. A filter of 0.001-inch iron foil was located in front of the detector slit for transmission and in front of the beam slit for back reflection. A new and improved specimen holder extended the useful tilting angle range for transmission to 70 deg instead of 60 deg as previously reported.&apos; A torque magnetometer was used to obtain the magnetic torque curves for a number of l-in. diam disk specimens. RESULTS The (110) pole figure of the material after recrystallization at 800°C is shown in Fig. 1. The positions of the pole concentrations are found to be

Jan 1, 1961

By C. T. Butler, W. W. Kay, R. D. Boddorff, R. L Ash

DRILLING and blasting in anthracite open-pit mines is a continuous problem to contractors and explosive engineers because of the diverse conditions caused by the nature of the geological formations, the extensive mining of the portions of coal beds near the surface, and the proximity of many strip pits to populated areas. Pennsylvania anthracite occurs in four separate long and narrow fields totaling only 480 sq miles. The coal measures are rock strata and coal beds that are considerably folded and faulted. The crests of the anticlines are eroded extensively. The beds outcrop on the mountain sides and dip under the valleys. At first only the upper portions of the syn-clines could be stripped. Now stripping to increasingly greater depths is economically possible, as is indicated by the fact that the proportion of freshly mined anthracite produced by strip mining has increased from 3.7 pct of the total tonnage in 1930 to 29.6 pct in 1950. Much of the rock overlying the deeper beds now being stripped is so extensively broken that considerable difficulty is experienced in drilling satisfactory blast holes and in using explosives in such manner as to insure a uniformly broken material easily removed by the excavating machinery. Such breaking of rock strata has occurred because the bed now being stripped has been mined extensively in former years by underground methods, and tops of gangways and chambers have subsequently failed. Draglines are used to uncover coal where the overburden can be moved with little or no re-handling. These machines range in size from those having a 2 cu yd capacity bucket on a 60-ft boom to those handling a 25 cu yd bucket on a 200-ft boom. Draglines are also used to strip to the bottom of the coal basins if the depth and the distance between the crops are not too great. For this type of operation blast holes are drilled full depth to the bed. These holes are commonly 30 to 90 ft deep; however, in exceptional cases, holes may be as shallow as 12 ft or as deep as 130 ft. Drilling is normally done for blasts of 12,000 to 60,000 cu yd of overburden, 30,000 cu yd being considered an average blast if vibration is not the controlling factor. Where the stripping of wide basins or the exposure of a moderately pitching vein makes the use of draglines impractical, dipper front shovels equipped with 4 to 6 cu yd buckets load into trucks. Overburden is removed in benches of 25 to 30 ft with blast holes drilled 4 or 5 ft deeper than the planned floor of the bench. For shovels under 5 cu yd bucket capacity the volume blasted varies from 8000 to 12,000 cu yd, whereas a volume of 30,000 to 50,000 cu yd of overburden is frequently blasted at one time for the larger shovels where vibration is not an important factor. During the past decade the churn drill, generally the Model 42-T Bucyrus-Erie blast hole drill equipped for drilling 9-in. diam holes, has become the most common blast hole drilling machine. Electricity powers half the churn drills in use and is preferred on the large strippings where electric shovels are operated and the working area is concentrated. On these operations the cost of additional electricity for the drills is less than the cost of fuel to operate diesel units because of the existing large demand load of the excavating equipment. Moreover, electric motors start more easily in cold weather and generally are less expensive to maintain. Diesel driven units are employed where a higher degree of mobility is required. The average drilling speed is 8 ft per hr, although in softer rocks a rate of 15 ft per hr is attained. Where rock is hard and strata is badly broken, drill speeds may be less than 2 ft per hr. Low drilling production results under these circumstances when loose material falling from the upper portion of the drill holes causes drill stems to be jammed. Rock formations vary so greatly in the region that a 9-in. diam churn drill bit may become dull after drilling only 2 ft or may drill satisfactorily for 56 ft; however, an average of 35 ft is usual in sandstone of medium hardness. Dull bits are hoisted to flat bed trucks by the sand line of the drill and are usually sharpened in the contractor&apos;s bit shop adjacent to the job. Care is generally taken to cover the thread end of the bit with a cap. To facilitate handling of bits around the drill, a heavy thread protector having an eye top is becoming more popular than the flat-top rubber or metal cap furnished with new bits. The 9-in. diam blast holes for a 25 to 30 ft bench are normally on 18x18 ft to 20x20 ft spacings, depending on the character of the overburden, although in broken ground 15x18 ft centers may be used to obtain better breakage and a more even bottom for the bench. The patterns of holes for shots

Jan 1, 1953