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By George H. Anderson

A CHAPTER of appealing interest was added to the industrial history of the Southwest early in June, when the War Production Board gave final approval to the erection of a blast furnace, a battery of coke ovens, an ore-beneficiation plant, and other facilities for the production of pig iron in northeastern Texas, just north of the East Texas oil field. For many years the people of Texas and adjoining states have cherished the ambition and desire that eventually an iron and steel industry drawing upon local mineral resources would be established to serve Southwestern markets. The existence in this vicinity of valuable deposits of iron ore, limestone, and coking coal has been known in a general way for many years, and efforts have been made from time to time to use them in the production of iron. The present development promises to bring to realization the dreams of the men who have visualized what the establishment of this basic industry would mean to the region.

Jan 1, 1942

By A. Lee Barrett

THE Maintenance Committee of the Coal Division of the American Institute of Mining and Metallurgical Engineers is presenting with this report the first of a series of cost comparisons which it plans to present to the Institute. The plan is to assemble maintenance cost on all equipment connected with mechanical operations at the face of coal mines, to arrange these costs by districts, to make comparisons between districts, and within districts. This particular report covers data with respect to mobile loading machines, including both "on-track" and "off-track" equipment. It is anticipated- in-fact, considerable data have already been accumulated-that next year complete maintenance costs by districts can be presented for complete loading units, including the various classes and combinations of on-track and off-track equipment. Data have also been collected with respect to some phases of maintenance methods and certain recommendations of the committee are included dealing with maintenance problems. In the assembly of these data more than 120 questionnaires were sent to operating companies through- out the United States. At the time the report was written 33 questionnaires had been returned with completed information and an additional group of companies had written that the information requested was not at present available but that they hoped to have such information available in the not far distant future. The replies as

Jan 1, 1946

By A. B. Fly

Borehole mining combines the principles of hydraulic mining, slurry mucking and rotary drilling. The borehole is drilled with conventional equipment and is cased down to the top of the mining zone. The borehole mining tool is comprised of the kelly-swivel assembly, multiple drill-pipe sections, and the jet-pump barrel assembly as shown in Fig. 1. The kelly swivel is fitted with a bail to support the mining tool. The kelly drive bushing engages the rotary table to allow the rotation of the mining tool while it is being operated. The jet-pump barrel assembly is comprised of the sidewall jet nozzles, the jet-pump assembly, the suction screen, and the tricone rock bit. Clean fluid is pumped at high pressure through the kelly hose to the high-pressure swivel on the mining tool. The high-pressure pipe conducts the fluid down to the sidewall jet nozzles, the pump jet nozzle, and the tricone rock bit. The sidewall jet streams cut the formation and wash the cuttings down to the rock bit. High-pressure fluid issues from the water courses to clean the bit and to agitate the cuttings. Rotation of the mining tool causes the rock bit to grind any oversize material enough to permit its passage through the suction screen. High- pressure fluid issues from the pump jet nozzle to provide the lift needed to pump the slurry to the surface. The slurry is discharged into the settling pits where the cuttings are deposited and the clean fluid is returned to the suction of the high-pressure pump.

Jan 3, 1969

By M. A. Westbrook, J. F. Redmond

A method is presented for obtaining porosities of consolidated formations from the drill returns. The method provides a means of determining the bulk volume of a large number of particles, such as drill cuttings, by employing a capillary diaphragm for removal of surplus surface liquid from saturated cuttings having pores of capillary size, which reduces tile amount of error present in former attempts to determine the porosity of drill cuttings. The method makes it possible to obtain a considerable amount of supplementary data on consolidated formations. Introduction Porosity is a direct measure Of the volume of the voids in a formation. It may be used for estimating the permeability of a formation provided that a correlation of these two properties has been obtained from the analysis of cores from the particular formation, and it forms a desirable aid in interpreting electric logs.1 These useful applications have emphasized the importance of developing a method for determining the porosity of the formations penetrated by a well by some means other than coring, for even in exploration wells it is neither economical nor practical to core all formations. Also, in wells where at the outset the coring program appears comprehensive, it is frequently found that, after certain layers are drilled. more complete information is required for evaluation. Porosity values, if obtainable, would be of great assistance in such cases. In soft formations it is usually possible to obtain porosities after drilling with cores taken by side-wall coring devices. In hard consolidated formations, that coring procedure is not alway practicable and other methods for determining porosities must be resorted to. A first choice is the examination of drill cuttings. if an analytical procedure is available that is both accurate and reasonably rapid. Such a procedure has been devised and is applicable to sand and limestone cuttings having pores of capillary size. Although imp,ovements can yet be made, it is believed that the new technique is sufficiently well developed to warrant description, Preparation of Sample The well samples containing the cuttings representative of the particular intervals are first washed through a No' 6 gauge screen. The cuttings remaining on the Screen are large enough to use lor the porosity measurements' From the sized sample, the cuttings to be examined are separated from the shale and Other extraneous particles. It is recommended that 10 to 15 c.c. of the selected cuttings be used for measurements, although only 4 to 5 c c. were used to make the comparative tests described later in this article. These cuttings are extracted and dried by the same methods used for preparing core samples for porosity and other measurements. The separation, which is at present being carried out by hand, is the most tedious

Jan 1, 1946

By M. A. Westbrook, J. F. Redmond

A method is presented for obtaining porosities of consolidated formations from the drill returns. The method provides a means of determining the bulk volume of a large number of particles, such as drill cuttings, by employing a capillary diaphragm for removal of surplus surface liquid from saturated cuttings having pores of capillary size, which reduces tile amount of error present in former attempts to determine the porosity of drill cuttings. The method makes it possible to obtain a considerable amount of supplementary data on consolidated formations. Introduction Porosity is a direct measure Of the volume of the voids in a formation. It may be used for estimating the permeability of a formation provided that a correlation of these two properties has been obtained from the analysis of cores from the particular formation, and it forms a desirable aid in interpreting electric logs.1 These useful applications have emphasized the importance of developing a method for determining the porosity of the formations penetrated by a well by some means other than coring, for even in exploration wells it is neither economical nor practical to core all formations. Also, in wells where at the outset the coring program appears comprehensive, it is frequently found that, after certain layers are drilled. more complete information is required for evaluation. Porosity values, if obtainable, would be of great assistance in such cases. In soft formations it is usually possible to obtain porosities after drilling with cores taken by side-wall coring devices. In hard consolidated formations, that coring procedure is not alway practicable and other methods for determining porosities must be resorted to. A first choice is the examination of drill cuttings. if an analytical procedure is available that is both accurate and reasonably rapid. Such a procedure has been devised and is applicable to sand and limestone cuttings having pores of capillary size. Although imp,ovements can yet be made, it is believed that the new technique is sufficiently well developed to warrant description, Preparation of Sample The well samples containing the cuttings representative of the particular intervals are first washed through a No' 6 gauge screen. The cuttings remaining on the Screen are large enough to use lor the porosity measurements' From the sized sample, the cuttings to be examined are separated from the shale and Other extraneous particles. It is recommended that 10 to 15 c.c. of the selected cuttings be used for measurements, although only 4 to 5 c c. were used to make the comparative tests described later in this article. These cuttings are extracted and dried by the same methods used for preparing core samples for porosity and other measurements. The separation, which is at present being carried out by hand, is the most tedious

Jan 1, 1946

By Theodore M. Barry

Work measurement is the most common of many titles given to determining the amount of human work required to do any job. A new technique-like most modern management tools-it still needs years of constructive research. Yet despite known imperfections, it is probably the most enthusiastically used tool of cost control developed in the last hundred years. Over 85 pct of all companies employing more than 100 workers in one of the major industrial areas use work measurement. For a good reason, however, this has not been true in the mining industry until very recently. The facts make an interesting story.

Nov 1, 1955

By P. J. Ehret

By and large, I agree with many of the precepts discussed in the Saperstein paper. I believe there is much more that can be done on the local level to involve both government and planning in the mine permit review process. Admittedly, much can be done to improve discussion between the state regulatory authority, local authorities, and mine operators. However, I strongly disagree, as suggested in the paper's conclusion, that such a system, as outlined in Saperstein's paper, could result in a reduction of review time or a lowering in the cost of permitting. The implementation of such a system by its very nature would only add a new level of bureaucracy to an already cumbersome process. This system, in my opinion, would only add to the cost of permitting and the time necessary to obtain a permit. Admittedly, it would achieve the result of adding local influence into the permitting process, but at what off-setting cost? It has been my professional first-hand experience and observation in the permitting and lands unsuitable processes to note that under the present system, local governments that do feel they have a stake in local mines and actively advocate their position (not simply comment), have had significant input into the conduct of mining and reclamation plans in their areas. Mining companies that mine in these areas are aware of local interests and attitudes, and do consider them in their plans. Simply put, local governments that want to get involved and want to play significant roles can and do. Those that do not advocate a position or have no input to offer do not. Although the present system is not as direct in effect in regard to local control as Saperstein's, it does work. It does so without the red tape that would result from developing miniature regulatory authorities in every county in which mining occurs. Although local input is important, there are many more sections of the Surface Mining Control and Reclamation Act (SMCRA) than Sections 508(a)(8) and 522(a)(3)(A) that also are important. It appears Saperstein's paper may overindulge these sections. An additional specific comment is made in regard to the statement that while local areas benefit from mining (wages, salaries, and purchases), they also endure environmental deterioration caused by mining affects. It is believed that the whole purpose for which SMCRA and its resulting regulations were enacted and developed was so mining would not be permitted if significant environmental deterioration could occur. Therefore, it could be argued that this point under current law is moot.

Jan 1, 1985

By Cyril S. Taylor, Junius D. Edwards

Magnesium is the lightest metal used for structural purposes, for which reason perhaps more than usual interest is attached to measurements of its density. Although the density of solid magnesium has been det,ermined frequently, no measurements of the density of the liquid metal are available. Because of unusual experimental difficulties in measuring the density of the liquid, only a limited number of measurements of good precision were secured. The results, especially the value for the crystallization shrinkage, are of great interest in connection with the casting of the metal. A number of samples for these measurements were made available through the courtesy of the American Magnesium Corp. They were in the form of extruded bars 3/8 in- in diameter and several were of exceptional purity, as indicated by careful analyses. Table 1 gives the density values (at 20" C.) for magnesium of varying degrees of purity. The density was measured at room temperature by comparison of the weight in air, and when immersed in distilled water. The necessary buoyancy corrections were applied, so that the density could be expressed in absolute measure—grams per milliliter. The effect of the buoyancy of the immersed suspension and the surface-tension pull of the water upon the suspension were eliminated from the results by a preliminary weighing of the suspension immersed to the working depth. Great care was necessary to prevent the introduction of a significant error by the formation of gas bubbles upon the clean magnesium surfaces; these are sometimes very minute and easily escape observation. They may be detached by raising the specimen from the water and again immersing; this should be done just prior to completing the weighing. Their formation may be almost entirely prevented during a measurement by previously immersing the specimen in a solution of paraffin in petroleum ether. The thin film of paraffin remaining after the evaporation of the solvent prevents wetting of the magnesium surface by the water. In one such determination, the paraffin coating on a 22-gm. Specimen

Jan 1, 1923

By Junius D. Edwards, Cyril S. Taylor

Magnesium is the lightest metal used for structural purposes, for which reason perhaps more than usual interest is attached to measurements of its density. Although the density of solid magnesium has been det,ermined frequently, no measurements of the density of the liquid metal are available. Because of unusual experimental difficulties in measuring the density of the liquid, only a limited number of measurements of good precision were secured. The results, especially the value for the crystallization shrinkage, are of great interest in connection with the casting of the metal. A number of samples for these measurements were made available through the courtesy of the American Magnesium Corp. They were in the form of extruded bars 3/8 in- in diameter and several were of exceptional purity, as indicated by careful analyses. Table 1 gives the density values (at 20" C.) for magnesium of varying degrees of purity. The density was measured at room temperature by comparison of the weight in air, and when immersed in distilled water. The necessary buoyancy corrections were applied, so that the density could be expressed in absolute measure—grams per milliliter. The effect of the buoyancy of the immersed suspension and the surface-tension pull of the water upon the suspension were eliminated from the results by a preliminary weighing of the suspension immersed to the working depth. Great care was necessary to prevent the introduction of a significant error by the formation of gas bubbles upon the clean magnesium surfaces; these are sometimes very minute and easily escape observation. They may be detached by raising the specimen from the water and again immersing; this should be done just prior to completing the weighing. Their formation may be almost entirely prevented during a measurement by previously immersing the specimen in a solution of paraffin in petroleum ether. The thin film of paraffin remaining after the evaporation of the solvent prevents wetting of the magnesium surface by the water. In one such determination, the paraffin coating on a 22-gm. Specimen

Jan 1, 1923

By Robert Uhley, Tsvi Meidav, L. Scharon

Before National Lead built an industrial plant on its Fredricktown property, some 100 miles south of St. Louis, a 750x500-ft area on the proposed site was investigated by electrical resistivity, seismic refraction, and churn drilling. Data were accumulated to prepare an isopach map of the overburden and to determine soundness of the dolomite bedrock and the depth to bedrock at fixed points. The site was on a gently sloping hillside. Elevations above sea level ranged from 760 ft in the northwest corner to 820 ft along the eastern edge, giving a total relief of 60 ft. There were no major drainage features, but in the northern part of the plant site there was an indicated depression area which later was interpreted as reflecting subsurface conditions in the bedrock. No rock was exposed in the entire plant site area; the surface was characterized by soil and overburden. GEOLOGY Prevailing geology in the area of investigation was relatively simple—Bonneterre dolomite overlain by residuum. The red overburden was that derived from the weathered Bonneterre. Some chert was present, interpreted in the general area as a weathering of both the Bonneterre dolomite and younger sedimentary rocks such as the Potosi dolomite. During the period of actual measurements the residuum varied from moist near surface on the western edge of the proposed site to dry near surface on the eastern edge, and for this reason overburden resistivities ranged from low on the west to high on the east. Seismic velocities were low, since the material was not well packed. The bedrock encountered was dolomite, specifically the Bonneterre of Upper Cambrian age which, according to McQueen,' consists of an upper dark gray member and a lower light gray member. These have been further divided into four zones, in ascending sequence a dark gray, sandy argillaceous dolomite; a dark brown or black, fine-grained dolomite: a light gray, finely crystalline, compact dolomite; and, at the top, a dark brown, finely crystalline, compact dolomite. In the area of investigation the upper two zones were encountered in the drilling tests as constituting the bedrock. The dolomite varies widely in porosity, which is low in the dense, fine-grained layers. In this area, therefore, both electrical resistivities and seismic velocities were high. Fracture zones in the Bonneterre are nearly Geology, and may extend to some depth, causing considerable deep weathering. It was realized that over deep fracturing the apparent resistivities

Jan 1, 1960

By S. H. Ash

lowest fatal injury rate in history conferences stress selling worker on safety international safety conference beneficial

Jan 2, 1951

Jan 1, 1942

By R. A. Pallanch

PROBABLY one of the most perplexing problems with which a mill operator contends is the proper evaluation of his mill results. True, he accurately determines his recoveries of metals and grades of products monthly, weekly, and often daily. These figures do not of themselves directly translate to mill economics. When one figure is unusually good there may be an offsetting circumstance. The advantage of high lead or zinc concentrate grade may be offset by poorer recovery; high lead recovery may be offset by poorer zinc recovery, or vice versa; and so on. Besides, grades or recoveries may not of themselves mean more than a reflection of the grade and character of the ore during the period under study. What the operator sorely needs is some one measuring stick that tells him when he has achieved his greatest return, regardless of grades or recoveries-for if he knows his methods and practices are yielding the optimum return he need no longer concern himself with the assays of products and tailings, or the corresponding distribution of metal values. At first blush it would appear that the obvious answer to this is the actual money return to the mill. Paradoxical as it may seem, however, money return does not make a dependable yardstick any more than do grades and recoveries, as ore conditions would vary enough to bring about greater money return during periods when the actual metallurgical work is not as good. The mill operator, of course, should always aim for the greatest return on the ore, once it is in the mill bins, with proper attention always to mill treatment cost. The need of a proper yardstick becomes more imperative with the increasing complexity of the problem. In the case of a simple, single-product operation on a fairly uniform ore, in which only one metal is of significant importance, the need is not great, as grade and recovery pretty well tell their own story. At the other extreme is the operation that makes three or four separate marketable products from a complex mixture of heterogeneous ores that vary tremendously in individual metal contents and ratios, degree of oxidation, and other characteristics, and in which gold, silver, copper, lead and zinc are all significant values. ECONOMIC RECOVERY The first attempt at obtaining a proper single yardstick for a fairly complex ore with which I am familiar is the use of the "Economic Recovery" term at the leadzinc flotation mill of the Sunnyside Mining and Milling Co., Eureka, Colorado. This method had been applied there early in Sunnyside flotation-mill history (not later than 1920) and credit for the innovation I believe belongs to Messrs. Kuryla and Marquand. The term "Economic Re-

Jan 1, 1947

By J. S. Billheimer, H. H. Reamer, B. H. Sage

Jan 1, 1949

By H. H. Reamer, B. H. Sage, J. S. Billheimer

Jan 1, 1949

By Anson Hayes

FOR the purpose of the following discussion the word "research" is interpreted as including all phases of development work on methods of manufacture, metallurgical characteristics, and uses of iron and steel. Research in the iron and steel industry then includes both plant re- search and laboratory research. Since iron and steel came into being, the steel consumer's plant and the steel producer's plant have been important factors in the development of the steel industry. Good minds have always been associated with both consumer and producer plants, so marked progress was made in the industry even when these were the only types of research and development groups in action.

Jan 1, 1937

By C. G. Brehm

THE anthracite-producing region is in the northeastern section of Pennsylvania, and has an area of approximately 484 square miles. It is divided geographically into three separate fields, known as the Northern, Middle and Southern. The Northern field, with Wilkes-Barre approximately at its center, is a basin about 60 miles long and almost 6 miles wide at its greatest distance across. Generally speaking, it may be said that the coal meas-ures in this field lie horizontally, or on slight pitches, and consist of from 11 to 19 veins of coal, varying in thickness from several inches to several feet. The intervening strata between veins may be composed of slate, clay, rock or shale, or a combination of several, and are sometimes very thin. This condition often causes a treacherous roof, therefore roof sup-port and the attending hazard of mining are problems of concern. The Middle field is made up of a number of small basins of not very great depth, and the measures, which are in like number to those of the Northern field, are varying inclinations running from nearly flat to steep pitches.

Jan 1, 1938

By H. Stigzelius

FINLAND'S recent mining history is both dramatic and pitiful in its shifting fortunes, dominated as it has been, by the country's proximity to the border zone of opposing dictatorships and social traditions; Fascism to the south, Communism to the east, and Democracy to the west. After 108 years under Russia's more or less harsh rule, Finland gained its democratic independence during the 1917 revolutionary strife in Russia with the official help of Germany and spontaneous help of other neighbors. The young nation was attacked by Russia in 1939 and again in 1941. It is common knowledge how the Finns fought with everything they had and everything they could get against their overwhelming adversary, and how by force of circumstances they landed in the Axis camp in 1941. Finland has never been known as a mining country in the same way as near-by Sweden, whose abundant iron and copper smelters during long periods so greatly contributed to the nation's welfare. Its largely barren, Archaean-granite geology long seemed forbidding. Some mining was done, to be sure; copper and tin at Pitkaranta near the Russian border, and lead and copper at Orijarvi. But towards the end of the last century the absence of a single producing mine cast a pessimistic shadow of truth over the Finnish poet Runeberg's words, that

Jan 1, 1946

HENRY M. HOWE, Bedford Hills, N. Y. (communication to the Secretary *).-Dr. Burgess would add to the value of this important paper if he would give us the carbon content of the steel made in the several charges, or, if this cannot be done, if he would indicate whether, as might he inferred from his paper, the teeming temperature is approximately constant and independent of the carbon content of the steel, or whether as would be expected, it varies with the content and is materially higher for low- than for high-carbon steel. If he could add to Table 3 the time of the several tests, that would be welcome. His Table 3 leads one to infer that, once the bath is melted somewhat more than flat, the temperature of the roof is nearly constant and is approximately the highest compatible with reasonable longevity. That is to say, the metal is heated by means of a roof and flame at nearly constant temperature. The temperature of the observed upper surface of the slag should reflect that of the roof approximately, and in Table 3 this seems to be true, the temperature of both rising toward the middle of the record, and again falling. The slag as the medium through which the heat passes from roof to metal, should be intermediate in temperature between the two, as it is here. But the temperature of the metal ought to rise continuously, unless when cold additions are charged, and this too seems to be. true, allowing for slight observational errors, the total rise from the first to the last spoon-test being 89°. The temperature drop of from 85° to 135° from the last spoon-test to the teeming is surprisingly great, suggesting that the spoon-tests represent the metal immediately beneath the slag, and therefore appre-

Jan 6, 1917

Spencer Gulf takes off from the Great Australian Bight cutting a 200 mile deep wedge of water into the South Australia coastline. A pale winter sun shines yellowly on the choppy surface of this body of water which is progressively more salty as it approaches Port Augusta at the head of the Gulf. Once Port Augusta thrived as a grain port and the speedy clipper ships began or ended their legendary races there. On the eastern shores of Spencer Gulf, farm land spreads away from the water's edge. The western side of the gulf meets marginal grazing land of acacia tree and salt bush. Part way down the gulf, there are two industrial towns facing each other from opposite shores; Port Pirie on the east and Whyalla on the west. These towns are like half brothers, the common parent being the founders of Broken Hill Pty. Ltd., (BHP) who began lead smelting at Port Pirie and discovered iron ore near Whyalla needed for the lead smelting process. The iron deposits later became the inspiration for BHP's iron and steel business.

Jan 10, 1964