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By Walter R. Hibbard, Ming-Kao Yen

VARIOUS rationalizations of preferred orientations in cold worked polycrystalline metals have been based on the operation of at least two,1 three,2 five,4 an indefinite number,5 and all,6 slip systems of the type occurring in single crystals. Pickus and Mathewson3 suggested that the cold rolling texture in face-centered cubic metals could be rationalized on the basis of two or more operating slip directions symmetrically disposed about the direction of flow in such a manner that the resolved shear stress factor is equal for all operating slip systems and lattice rotations cancel each other. The importance of the direction of flow, † the necessity for the operation of slip systems capable of producing the required, changes in external dimensions, the maintenance of a common surface between adjacent grains and a symmetrical arrangement of the operating slip systems in order to produce an end orientation which is stable under additional deformation lead to the following rationalization of textures based on the type of slip systems operative in single crystals. The rationalization is intended to explain why certain orientations are suitable for deformational flow without a change in orientation and thus are stable end orientations or ideal texture orientations. It does not attempt to explain how the grains of a randomly oriented polycrystalline aggregate will reach this orientation. The rationalization is based on the following four postulates: I. The ideal textures for polycrystalline aggregates are the result of reorientations of individual crystals toward the same stable end orientation at which no further reorientation will occur even during additional deformation. Since, in simple slip, - the relative orientations of the stress axis and the active slip system determine the change in orientation during slip, it is considered that the orientation of the stress axis with respect to the ideal texture determines what slip systems must be active to retain the stable end orientation. Therefore the stable end orientation should be a symmetrical one around the stress axis with respect to the active slip systems such that lattice rotations resulting from slip will cancel each other and prevent a resultant change in orientation. (Rotational symmetry only-not translation, inversion, nor others-is considered here.) Thus a metal under a pure stress should develop a texture consisting of one or more of the crystallographically symmetrical directions, <100>, <110> or <111> for cubic metals or <0001>, <1010> or <1120> for hexagonal dose-packed metals, parallel to the stress axis. 2. Since the active slip direction is the direction of glide during simple slip and thus the direction of maximum shear movement, in the ideal texture the active slip

Jan 1, 1948

By Walter S. McKee

When mixed with common cast steel in quantities ranging from 11 to 131/2 per cent. and properly treated, manganese increases the ductility of the metal and adds greatly to its toughness and resistance to abrasive action, which properties comprise the distinctive characteristics that make manganese steel so valuable for many purposes at the present time.. * At present the manganese-steel foundries of this country have an annual capacity of about 60,000 tons and most of the growth has occurred within the past 10 years. In the early days of the industry it was impracticable to make manganese castings weighing over a few thousand pounds, but at present crusher heads, rolling-mill pinions, and similar castings weighing up to 30,000 Ib. each are produced, and it does not appear that the limit of weight has been reached by a considerable margin. Manganese steel is similar in analysis to ordinary first-class converter metal except that it is high in carbon and contains from 11 to 13.5 per cent. of manganese. From one standpoint manganese steel is similar to malleable iron in that the casting as it comes out of the sand is hard and brittle and must be made ductile by a heat-treating process. The heat treatment is an essential part of the process of making manganese-steel castings and must be properly carried out to secure satisfactory results. The necessity for heat treatment limits the thickness of sections which may be made of manganese steel. Originally the annealing depth was comparatively small, but researches carried on during the past few years have resulted in an increase in the thickness of section up to 51/2 in., which it is possible to treat successfully. Large castings are cored out to a minimum thickness of 51/2 in., thus not only eliminating some of the internal stresses which are invariably set up in a very thick casting, but also reducing the weight and inertia of the piece, an important consideration if the casting is to be a moving part in a machine. At the same time, the thickness of 51/2 in. is sufficient to permit the use of manganese steel for the heaviest classes of machinery.

Jan 1, 1916

By David B. Brooks, William A. Wallace, James R. Dunn

As the conflict between the mineral industry and preservationists steadily increases, it becomes urgent to determine as precisely as possible the costs of developing vs. not developing our domestic mineral resources so that enlightened mineral policy decisions can be made. A simple discounted cash flow equation is suggested as an approach to assigning a public-interest dollar value to mineral resources. Present value of a piece of land underlain by a mineral resource is taken as equal to the discounted cash flow derived from the resource corrected for present and future surface land values. The equation is effective as a base for mineral aggregate resource planning for metropolitan areas if transportation cost differences are substituted into the cash flow component. Suitably modified, the equation can be fitted readily into an existing computer simulation program for aggregate mineral resource planning in metropolitan areas. However, because of the lack of accurate input, the equation is less effective for other mineral commodities such as base metals and coal. Nevertheless, within a somewhat philosophical context, the equation still has utility and is effective in defining the problem of public interest values for minerals other than mineral aggregates.

Jan 1, 1972

By W. W. Scott

The application of engineering methods to the problems connected with drilling and producing in the oil industry has led to the development of the science that is variously termed "petroleum engineering," "production engineering," "petroleum production engineering," and even Itpolitical engineering." It would require much detail to enumerate the qualifications of a petroleum engineer, just as it would for an engineer in any major industry. For those who have a genuine liking for the oil industry, there is a wide selection of pathways to achievement. The oil industry is now highly specialized. Its products are necessary to all civilized people and are indispensable in the security of our nation and also in the well-being of our families. The business structure of our country depends in a large measure upon oil, and the welfare of this group as individuals is certainly linked with the welfare of the oil industry. What Is the Trend of Engineering? The oil industry offers a fertile field of opportunity for engineering; probably more so than any other industry. The sciences of geology, physics, chemistry and mathematics are all used in some phase of the oil industry and to a very considerable extent in the production division, which embraces the geological, drilling and producing departments. In drilling and production alone, research programs of considerable magnitude are being carried on at this time, and no doubt the future will see a great deal more of this kind of work. Through the cooperation of the engineer, the equipment manufacturer, and the American Petroleum Institute, immense savings have been made by the standardization of drilling and production equipment. Drilling equipment in itself offers a wide scope for study, in that continued efforts are being made to improve the equipment so that it can be made to drill faster and to greater depths. The improvements in drilling equipment are required because new reserves of oil are being found at progressively greater depths. In order to produce such oil in competition with oil now being produced from reservoirs

Jan 1, 1937

By Erwin L. Zodrow

A geological model of the modes of formation of magnetite and its distribution in the Smallwood iron-ore mine, Labrador, Newfoundland, is given, based on observation and geological mapping. This is called the conceptual model. If mathematical expressions plus probabilistic uncertainty are used to represent the conceptual model, then this is termed a mathematical model. The purpose of this paper is to test if there exists a correspondence between the conceptual model and two related mathematical models (called factor analysis). Details of the statistical technique are given. The results of factor analyses in relation to the magnetite formations in the Smallwood mine are discussed. Several practical mine applications are presented. The difficulty of maintaining quality control over ore mined from any deposit naturally depends on geological conditions; these are usually imperfectly known to concerned mining geologists. One geological condition that would greatly facilitate ore predictions is if a relationship between the observed ore particle distribution* and its mode of origin could be demonstrated. Such a casual interrelationship is normally sought through the application of well-defined geochemical principles of primary mineralization in given geological environments. However, the application of conventional tools of geological research, including geochemistry, to areas that have undergone repeated periods of geological deformation and metamorphism subsequent to primary mineralization becomes rather difficult. More important, the interpretation of such research results are nearly impossible on an objective basis. Mineral assemblages may have been reworked and changed due to tectonic influences to the extent that the present-day observable mineralogy and ore-particle distribution can effectively obscure the mode of origin of the ore. Quantitative measurements, based on petrological investigation of mineral assemblages, reflect the sum-total of all geological influences. Which of several influences had the most effect on existing ore particle distribution is difficult to assess, for these influences can neither be measured directly nor quantified by petro-logical logical or geochemical means. The present study is concerned with the magnetite distribution and its modes of origin within the Small- wood mine,&apos; located in the southern extension of the Labrador geosyncline; see Fig. 1. This geosyncline is thought to have undergone at least two periods of geo-tonic tectonic deformation, separated in time, since the fer-rugenous rugenous sediments were deposited." Detailed geological observations and mappings (1 in. to 40 ft) have highlighted subtle, distinctive features of the magnetite distribution in the Smallwood mine: (1) The magnetite is generally concentrated in bands or layers within this ore body; these bands alternate with specularite-rich bands and quartz bands. The banded or layered nature is common in Precambrian iron-ore deposits, and this has been interpreted as a result of changes in depositional environments. (2) The grain size of the magnetite varies; near the contacts between the iron and quartz-carbonate formations, the magnetite occurs as well-crystallized octa-hedra. In areas of intense folding, magnetite is extremely fine grained and concentrated in bands and occurs in association with earthy manganese minerals. (3) Magnetite tends to be more highly concentrated near the geological contacts of the iron and quartz-carbonate formation in the northeast part of this mine, Figs. 2, 3, and 4. (4) Magnetite is also fine grained and tends to higher concentration near and parallel to fold axes; however, in this case, the ore is much softer than given in item 2. (5) Magnetite mineralization decreases along strike and away from the areas of intense folding, i.e., towards the approximate center of the mine, Fig. 3. How can these variations of magnetite be explained on a geological basis? We can postulate a conceptual model that the distribution of magnetite appears to be related to three basic geological influences: (1) geo-tectonics, i.e., concentrations of magnetite near geological contacts of the iron and quartz-carbonate formations, the fine-grained nature of magnetite and its higher concentrations near fold axes, and decrease of magnetite towards the approximate center of the mine; (2) secondary alterations, i.e., variation of grain size of magnetite near the iron and quartz-carbonate contacts, and in areas of intense folding where magnetite occurs together with earthy manganese minerals: (3) original

Jan 1, 1971

"The Washoe Smelter is situated about two miles east of the City of Anaconda. The smelter site includes about 240 acres and peculiarly adapts itself in topography to the efficient handling of material. By reason of its being on a hill side it is possible to make the level of delivery of the product of one building the level of the charge floor of the next succeeding one.THE ORES: The ore treated comes principally from the Butte district and is hauled by the Butte, Anaconda & Pacific railway, a distance of twenty-eight miles, in trains of fifty 50-ton bottom-dump cars to the railroad yards at East Anaconda. At this point these trains are• split up according to their destination,—that is, as to whether they go to the concentrator and sampling mill ore bins, or to the storage bins. In each case they are made up into trains of eight or sixteen cars, according to the size of engine to be used, and are carefully weighed before delivery to their respective bills.Some idea of the magnitude of the works may be obtained from the following figures:Amount of ore that can be treated in 24 hours…12,000 tonsLime rock from adjacent quarries…2,300 tonsCoke used…500 tonsCoal for reverberatory use…500 tonsCoal for power use…50 tonsWater, per minute, 35,000 gallons.Men employed in and around Anaconda, 3,000. Monthly payroll for above, $300,000.00."

Jan 1, 1913

By Lawrence A. Garfield

From the bottom of a shallow fissure the near-naked man-animal hacked out a hand-sized chunk of the red rock-like material which, when beaten between other rocks, could be drawn out to the thinness of a flint edge. Unlike flint, however, it did not shatter when, as the point for a spear or arrow, it went wide of its mark and fell amongst the rocks or tree branches. For this reason and others, the red rock- like material was specially sought and much time was spent in trying to break it from the real-rock in which it grew. Only infrequently was a chunk broken free and in this area many hours had been spent to win but a few fragments. What luck then, to remove so large a piece where before nothing but real-rock dust formed whenever the stone hammer hit. Why did this happen? Did yesterday&apos;s food-fire, burning on top the red rock, loosen its hold on the real-rock and cause it to break free when struck with the stone hammer? It is not a matter of recorded history that the first heat assisted extraction of native copper from country rock occurred under the circumstances or in the manner related but it is known that crude mining operations using these techniques were conducted by primitive man. In this way the first mineral production may have been achieved and the original example of rapid excavation unknowingly given to the world. Rapid excavation is not a method of removing rock or ore from an insitu condition nor does the term refer to a type of equipment which is specifically employed in mining and underground construction. It is, rather, the nomenclature currently popular in industry-primarily in underground construction- relating to a comparative rate of performance.

Jan 1, 1971

By Chester Purington

THE AUTHOR hopes that this paper will meet with criticism and debate by fellow members of the Institute rather than with that attitude of passiv-ity and indifference which one is inclined to adopt when considering a field completely foreign to one&apos;s own experi-ence. After several years of study of voluminous literature, maps, and statistics, and many personal journeys and field inspections of various parts of Siberia, the conclusion is reached .that the area adjacent to the Stanovoi, Zhugd-Zhur, and Yablonoi ranges as below defined is that which .is most accessible to the western world and will soonest give results from exploration. HISTORY The first incursion of the Russians into Siberia east of the Yenesei River appears to have been in 1632 when the fort of Yakutsk was founded on the middle Lena. The early expeditions were in quest of furs. As the Siberians say, "the sable beckoned" and the post of Anadyr was founded in 1639, two thousand miles further northeast. Thus nineteen years after the Pilgrims landed in Massachusetts, the Russians had established a trading post within 700 miles of what is now the town of Nome, Alaska. Parties of Cossaks penetrated to the shores of the Okotsk1 Sea early in the seventeenth century, but it was not until 1688 that the town of Okotsk was founded. In 1712 a grand project was elaborated at St. Petersburg for building a port at Okotsk, but it came to nothing. Vitus Bering, the Alaska explorer, built ships at Okotsk, and made this his point of depar-ture. It is stated that the iron work used in these ships was brought overland partly from Yakutsk, and partly even from St. Petersburg, 5500 miles away. Accord-ing to report a copper deposit was worked on the river Urak, not far from the coast, and copper was smelted for sheathing the bottoms. Grassgrown mounds con-taining slag and shots of copper were inspected by the writer last summer, at the site of the ancient shipyard.

Jan 11, 1923

By F. A. Hames, D. S. Eppelsheimer

The ferromagnetic copper-manganese-aluminum and copper-manganese-tin alloys (Heusler alloys) owe their ferromagnetism to the beta phases (body-centered cubic structure) in their respective systems.l,2,3 The ternary beta phase regions in these systems are extensions of the beta fields of the binary copper-aluminum and copper-tin systems into the ternary models of the copper-manganese-aluminum and copper-manganese-tin systems respectively. X ray analysis has indicated the presence of long-range order in the more strongly magnetic alloys.3,4,5 The ideal ordered structure is obtained in alloys of compositions Cu2MnAl and Cu2MnSn; the copper atoms occupy positions at cube centers while the aluminum (tin) and manganese atoms alternate at cube corners. This atomic arrangement is illustrated in Fig 1. The compositions Cu2MnAl and Cu2MnSn are also those that show maximum magnetic saturation moment. 3,4,6,7 Departures from these compositions result in a decrease in the degree of order attainable and a decrease in magnetic saturation moment. In view of the chemical similarities of aluminum, tin, indium, and gallium, and the existence of beta phases in the binary systems copper-indium and copper-gallium, it may be suspected that ternary beta phases exist in the systems copper-manganese-indium and copper-manganese-gallium, and that these are ferromagnetic. The purpose of this investigation was to determine whether ferromagnetic beta phases exist in the systems copper-manganese-indium and copper-manganese-gallium analogous to the ferromagnetic beta phases in the systems copper-manganese-aluminum and copper-manganese-tin. Previous Work At the time this investigation was started no information could be found regarding the constitution of copper-manganese-indium and copper-manganese-gallium alloys, nor of the binary manganese-indium and man-

Jan 1, 1950

By Henry Rogatz

During the year 1937, there were 663 oil wells drilled in the Texas Panhandle, making a daily initial production of 322,332 bb1.—that is, 191 more oil wells drilled than in the previous year, with an increase in the total daily initial production of 66,283 bbl. The total daily potential of the field as determined by the Texas Railroad Commission in its Schedule of Dec. 17, 1937, was 1,039,982 bbl., or an increase of 205,094 bbl. over the previous year. On Dec. 17, 1937, the daily allowable of 68,578 bbl. was assigned to the entire field. The total amount

Jan 1, 1938

Pumping coal to market may help Appalachian coal operators increase their share of the eastern seaboard fuel business. Transporting it by pipeline is already an accomplished fact, but until recently it had to be dewatered to be used in boiler furnaces. The campaign for these eastern markets was begun in earnest last November by the widely publicized announcement of successful plant-scale firing of a central station boiler with coal slurry pumped to the burners. This latest advance makes coal similar to oil and gas in convenience in handling and controlling at the consumption end of the pipeline. Slurry could be considered a new commodity for the fuel market. HUGE POTENTIAL MARKET The heaviest concentration of power plants in the U.S. is along the line Washington, Baltimore, Philadelphia, New York and Boston which makes this region the best hunting ground for selling pipelined coal brought from western Pennsylvania and northern West Virginia. Furthermore, if this region is assumed to consume 125 million tons of coal annually, on a comparable basis, the consumption of oil and gas would be about 180 million tons. Even if all of this fuel is not consumed in central stations, it is still a very big market for coal at the right price. Consolidation Coal Co. and Texas Eastern Transmission Co. are trying to line up customers in this area so that a pipeline can be built. This is not to say that there are not many other areas in the U.S. that could not be supplied advantageously by a mine-to-market pipeline.

Jan 1, 1962

OLIVIA&apos;S recent revolution, by hindsight, seems to have been inevitable. The misery of the majority of the people, coupled with the economic crisis engendered by the refusal of the United States to meet Bolivian demands for a higher tin price, gave the National Revolutionary Movement party all the excuse it needed for overthrowing the government. Most of the mines in Bolivia are owned by three families. Precisely what it will mean to the United States is still a moot question. Argentina, with a mixture of Marxism, Fascism, and few twists created by the Perons, is in a position to grab off much of the tin we need. Because of the contingencies of geographical location, language and a natural simpatico, Argentina may be able to continue its efforts to oust the United States from its South American markets. Point Four aid was supposed to be given to Bolivia, but only for agriculture. Even this was entirely too slow. Mining, Bolivia&apos;s other major source of income was forgotten by the Washington planners. Primary aim of the new power will be to diminish its dependence on the world tin market. At a time when the free world is fighting a battle for control of metal, it stands a chance of losing an important source of supply. With the accent placed on agriculture and other industries, mining in Bolivia is certain to suffer. Argentina will be in a position to get the available supply of tin, make a strong ally in the world order of things, and add to its power play against the United States in South America. Ten labor groups have formed the Bolivian Central Workers Union. The first item on their list for immediate action is the nationalization of the mining and railroad industries. They also came out for agrarian revolution and diversification of industry. President Victor Paz Estenssoro has promised to appoint a committee for the investigation of nationalization of the mines. At least, this is indicative of a feeling for the need for caution.

Jan 1, 1952

By Robert Maes, Robert de Strycker

The Cu-Sn-As systeM was studied in the region near the Cu-42 and (214-As binary diagrams, where reactions in the solid state appear, resulting from the decomposition of the y(Cu-Sn) phase and from the formation of the 7 phase (Cu,As). The techniques used were microscopic observation, thermal analysis by dilatometry, and X-vay diffraction. The formation of the 7 phase gives rise to a ternavy pevitectoid veaction; the decomposition of the y phase gives rise to five transitional reactions. The temperatures of almost all these reactions could be determined; in the most favorable cases , the accuracy of this determination was of 11.5-C. The 7 phase is stabilized by tin additions, the arsenic atoms being replaced by tin atoms up to 35 pct; this has allowed the preparation of pure j) phase and the confirmation, by extrapolation, of the conrposition of this compound in the Cu-As diagram. In the first part of this work, the solidification reactions in the Cu-Sn-As phase diagram were studied. In the copper corner, the structure of the alloys presented the evidence of reactions in the solid state: on the one hand, all the alloys containing the y phase of the Cu-Sn diagram showed, under the microscope, that this phase had formed different decomposition products after complete solidification; on the other hand, the appearance of the 7 phase of the Cu-As diagram necessitated the introduction of a peritectoid formation reaction. The study of the decomposition of the y phase has been done by preparing about forty alloys that were homogeneous y at high temperature. The formation of the 7 phase has been studied by means of a few alloys with a composition near the homogeneity field of this phase at room temperature. The part of the Cu-Sn phase diagram of interest for this study is represented by Fig. 1, with the phase designation which will be used in the remainder of this paper; it is drawn after Hansen and Anderko.&apos; The Cu-As diagram has already been presented in Part I of this work; the significant features of this study are the existence of the arsenides CusAs and Cu5Asz, and the formation of a compound CUEAS, designated as the 7 phase, by a peritectoid reaction at about 325°C. EXPERIMENTAL METHODS The fundamental technique for the investigation of this part of the Cu-Sn-As constitution diagram was microscopic observation; the greatest part of the observed alloys has also been subjected to thermal analysis by dilatometry; a few selected alloys have then undergone an X-ray analysis by powder diffraction. Alloy Preparation. The alloys were prepared from the same products as in Part I of this study: cathode copper, arsenic with a purity better than 99.5, and tin with a purity of 99.98. The fusion of the ternary alloys was realized from

Jan 1, 1967

By Frank Julian

After the solution of an iron ore, or metallic iron, in an acid, for the determination of phosphorus, it is necessary to evaporate the solution to dryness and to heat the residue to effect the complete separation of silica. Authorities differ as to the temperature required, some recormmentling not over 100&apos; C., others as high as dull redness. For the purpose of securing some indications as to the degree of heat which may be safely or advantageously employed, I selected a gray pig-iron, a piece of Bessemer steel rail, and a sample of Ludington ore having the following composition; the phosphorus in the pig and steel being determined by Giutl&apos;s ferric chloride method:

Jan 1, 1884

By Arthur Taggart

IN 1900, Elmore found that if an acidulated pulp was stirred up with an oil which was relatively insoluble in and lighter than water, and the mixture was al-lowed to stratify, much of the sulfide would be found hanging to the lower surface of the floating body of oil and could be skimmed off or overflowed with it. The action of the flotation agent here is two-fold, first to select the sulfide from the gangue-what to-day is called collection-and second, to buoy the col-lected sulfide away from the gangue. The action in collecting is illustrated by Fig. 1, which contrasts the behavior of drops of oil brought, under water, to the surfaces of gangue and sulfide particles, respectively. The oil displaces water from the surface of the sulfide; the water displaces oil from the gangue surface. If, instead of considering the solid particles the fixed parts of the system of oil, water and solids, we consider the oil and water fixed and the solids pre-sented to the surface of contact, the condition will be as shown in Fig. 2 ; the sulfide tends to be drawn into the interface and the gangue to be excluded. The sul-fide particles are held in the oil-water surface by the tension of this surface. The buoyant effect is supplied by the oil droplets in bringing the sulfides to the water surface, but not in holding them there.

Jan 6, 1928

By Herbert Clark Hoover, Lou Henry Hoover

QUESTIONS as to the methods of smelting ores and of obtaining metals I discussed in Book IX. Following this, I should explain in what manner the precious metals are parted from the base metals, or on the other hand the base metals from the precious&apos;. Frequently two metals, occasionally more than two, are melted out of one ore, because in nature generally there is some amount of gold in silver and in copper, and some silver in gold, copper, lead, and iron ; likewise some copper in gold, silver, lead, id iron, and some lead in silver ; and lastly, some iron in copper2. But I will begin with gold. Gold is parted from silver, or likewise the latter from the former, whether it be mixed by nature or by art, by means of aqua valens3, and by powders which consist of almost the same things as this aqua. In order to preserve the sequence, I will first speak of the ingredients of which this aqua is made, then of the method of making it, then of the manner in which gold is parted from silver or silver from gold. Almost all these ingredients contain vitriol or alum, which, by themselves, but much more when joined with saltpetre, are powerful to part silver from gold. As to the other things that are added to them, they cannot individually by their own strength and nature separate those metals, but joined they are very powerful. Since there are many combinations, I will set out a few. In the first, the use of which is common and general, there is one libra of vitriol and as much salt, added to a third of a libra of spring water. The second contains two librae of vitriol, one of salt-petre, and as much spring or river water by weight as will pass away whilst the vitriol is being reduced to powder by the fire. The third consists of four librae of vitriol, two and a half librae of saltpetre, half a libra of alum, and one and a half librae of spring water. The fourth consists of two librae of vitriol, as many librae of saltpetre, one quarter of a libra of alum, and three-quarters of a Mbra of spring water. The fifth is composed of one libra of saltpetre,

Jan 1, 1950

By Thomas V. Falkie, Robert Stefanko

Much has been said and written recently about the manpower problem in the mining industry. The coal segment of the industry has been scrambling to staff and man its companies and operations in order to accommodate the current boom, and there are some interesting side- lights and developments which deserve further attention from coal mining people. This column will deal with the manpower problem in general and the plight of the professional-the mining engineer-in particular. At this point in the game, it is desirable and perhaps necessary to ask ourselves if there really is a manpower problem and, if so, how serious it is. Suprisingly, there are varying and conflicting answers to this question. If we are talking about warm bodies, then in most mining areas there is no problem. If, however, we are talking about skilled or trained people-at all levels-there are apparently serious shortages, especially in the coal industry and in the U. S. Bureau of Mines. To define quantitatively the present and future need for mining professionals is a formidable task, to say the least. Without pretending that these figures are anything but an educated guess, we feel there is an immediate need for about 1000 mining engineers right now and a continuing need for about 300 mining school graduates per year (double last year&apos;s number) for the next ten years in order to take up the slack, provide for attrition and maintain a normal growth rate. Mining companies, large and small, are just now beginning to realize that the industry is undergoing a revolution, It is no longer possible to design, build and operate coal mines by the "seat of the pants." Production demands, the new health and safety law and the inevitable new legislation on surface mining will require more engineering, more planning and new technology. There are mine operators who need mining engineers and don&apos;t even know that they need them. This could mean rough going for the small operator. It surely means that there will be a trend toward increasing the ratio of technical to nontechnical employees and the ratio of technical employees to dollars of capital towards levels comparable with other highly mechanized industries.

Jan 1, 1971

By G. Vaux, M. L. Fuller

AN apparatus and procedure for the determination by X-ray reflection of preferred orientation of crystals in rolled metal with the Geiger counter X-ray spectrometer was described by Schulz.&apos; This is an excellent procedure and we have used it continually for several years. In our use of the procedure, two modifications have been made and used during most of this period. One of these provides for automatic scanning and recording of the reflections, and the other makes possible the application of the procedure to coarse-grained specimens and permits measurement of almost all orientations without resort to the transmission technique. The automatic scanning and recording are accomplished by a motor drive of the inner ring of the Schulz apparatus (see R, in Fig. 2 of his paper and R2 in Fig. 1 of this note) in synchronism with the chart recorder of the North American Philips 90" X-ray spectrometer. A rate of 10" per min is used. A scan of 180" is obtained corresponding to poles on the stereographic projection whose locus is a great circle. The modification for coarse-grained material is accomplished by allowing a larger area of the specimen to contribute to the X-ray diffraction. In the Schulz apparatus the incident X-ray beam is confined by a slit system to rays in the plane of the spectrometer. Schulz demonstrated that this restriction of the X-ray beam permits a survey of the X-ray reflections without correction up to about 80" on either side of that specimen position in which the specimen is perpendicular to the plane of the spectrometer. This is the angle + of rotation of the inner ring R2. One of these slits is horizontal and extends across the X-ray source side of the specimen. In the modification this slit is removed, thus permitting greater divergence in the X-ray beam and the irradiation of a larger area of the specimen surface. Fig. 1 shows the apparatus with the motor drive and with the slit removed. Discontinuities in the recorded X-ray intensity plot due to the few participating crystals in coarse-grained metal are much lessened. The increased divergence does not cause reflections from other crystal planes to enter the Geiger counter slit. An important advantage of the original Schulz scheme is thus lost and a system for correction is required. To do this, a compact of atomized copper powder was prepared and tested by the original Schulz method for the absence of preferred orientation. The horizontal slit was then removed and a curve recorded showing the variation of intensity with angle +. In our arrangement the intensity was uniform within the range + equals ±30°. Beyond this the intensity fell off rapidly reaching zero at ±90°. The curve thus produced is then used to correct measurements made on preferred orientation specimens. In practice this is accomplished by constructing from this calibration curve a family of curves which, as a transparency, can be superimposed on the recorder chart to read corrected intensity directly. Not only does this method permit the handling of coarse-grained material but it also makes possible the plotting of intensities almost to the circumference of the stereographic pole figure projection. Thus, nearly the entire pole figure can be plotted without the necessity of using the transmission technique. Moreover, intensities are much greater, an advantage when surveying crystal planes of poor reflecting power.

Jan 1, 1954

By David A. Summers, Clark R. Barker, Marian Mazurkiewicz

In May 1975 the U.S. Bureau of Mines contracted with the University of Missouri-Rolla, Rock Mechanics and Explosives Research Center to develop a Hydrominer modification to a longwall shearer unit, wherein the rotating pick-laced drums and connecting gear drives are replaced by a water jet cutting ahead.1 The concept of the water jet cutting head is based on using the high localized energy of the water jets to isolate a slice of coal by cutting a slot under, at the back of, and at the top of the web. The plow blade of the head then advances into the cut and wedges the coal cantilever over onto the conveyor (Fig. 1).

Jan 4, 1978

By P. J. Shenon

ENROLLMENT in geological and mining engineering curricula is declining at an accelerated rate despite the greatest need for trained men ever extant in the minerals industry. Industrial and military demand is mounting, but the number of freshmen selecting the mineral field continues to fall. Estimates on the needs of industry range as high as 30,000 new engineers a year. The current deficit is more than 60,000 engineers less than the 350,000 to 450,000 which eventually will be needed. The indisputable fact is that the colleges are turning out fewer and fewer engineers despite the greatest enrollment in colleges and universities ever experienced in the United States. In 1950 a record 52,000 young men stepped out of the confines of ivy covered walls with engineering degrees in their hands. By 1951, however, the number dropped to 41,000 and present enrollment indicates a national graduating class of only 25,000 for 1952. No letup in the drop is forecast. About 19,000 can be looked for in 1953 and 1954 may reach an unhappy 12,000. It becomes clear that something must be done to attract high school graduates to engineering. One immediate possibility could be to make the course burden carried by the engineering student somewhat lighter. The prescribed curriculum in many schools is such that the student takes the path of least resistance, and instead of training for an engineering future, studies for a vocation which will allow him to learn and at the same time get at least a nominal enjoyment out of college life. Review geological and mining curricula of 20 colleges and it will be found that the engineering student is a veritable pack mule compared to a lad taking liberal arts or some other non-technical program of study. The curriculum for geological engineering at one school calls for 202 semester hr, with almost 23 hr carried per semester. Multiply this figure by three hr, the minimum supposedly to be devoted to a credit and you get 69 hr per week. With a bare minimum of 84 hr for sleeping and eating, about two hours a day remain for recreation. However, the load of other schools investigated is about 19 hr. The University of Utah requires 238 quarter hr for graduation with a degree in geological engineering, while requiring only 183 quarter hr for baccalaureate degree from University college, Utah&apos;s liberal arts school. It can be stated with a measure of surety that the same proportions exist in other universities. The first step would be for ECPD to review its requirements for mining and geological engineering. It must recognize that mining and geological engineers operate in a specialized field, as do other types of engineers. Although a geological engineer may not design a bridge, as pictured by the ECPD Committee on Engineering Schools, his field of design calls for similar engineering precision, a knowledge of materials, construction methods, economic considerations, and financing. Six schools have been accredited by the ECPD. What is the basis for approval and can the requirements be modified and still be kept in line with the needs of the geological engineer? Course work from school to school varies with the exception of mathematics, chemistry, and physics. Even in those courses the not inconsiderable variation lends dubious creditability to the mean. One accredited school requires 7 1/3 semester hr of chemistry, compared with 24 hr required by another, making an average for the six schools of 17 1 /3 hr. Required credit hr in mechanics ranges from 4 to 18 and in surveying from 2 to 15. Several non-accredited schools require more hr than do the accredited schools in some courses. Why is the engineering student forced to carry such a back-breaking load? The answer is of course fairly obvious. He is irrevocably set apart from the rest of the student body because of the nature of his life&apos;s work. He is training for a place in a world where technology is becoming increasingly involved. He must be prepared to do a job now-and not later. Mining and geological engineering require the same essential backgrounds as other engineers, and more. The "more" is a knowledge of mining methods, metallurgy and geology for the mining engineer. The geological engineer must know in addition, mineralogy, petrography, and geophysics. The load is compounded finally by the addition of liberal arts courses. Should anything be done to relieve the situation? Today&apos;s engineer must be a whole man, capable of handling the tools of communication and with an understanding of the economics of industry. He must be able to write clear simple English, and he must be man who can think from some other position than bent over a work table. He must be aware of the history of his country and to some extent that of the world. Not all schools share this view. Only two of the accredited schools require history courses. However, five of the non-accredited schools make it mandatory. Four accredited and five of the nonaccredited schools require economics. Courses in mathematics, physics, and chemistry are fundamental in engineer training. The average for the accredited schools could serve as a guide in

Jan 1, 1952