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By George W. Riter

A distinguished engineer, the active head of a large mining company, has said that surveying attains the dignity of a profession only in the hands of a few men—the few who know how to keep notes that will be understood by even a novice without further word of explanation. Of all mine-records, survey notes are perhaps the most important. The maps made from them serve as a working-guide, and as framework for other data; and when, from any cause, access to underground workings is shut off, the surveyor's record often becomes invaluable. So seldom docs a surveyor have a chance to check underground surveys by making a closure, that he is compelled to rely on the precision of each step of his work for the accuracy of the final result. When data are fully recorded on the spot, the notes, even in the hands of second parties, become evidence of the care and precision with which the surveying was done. It is worth a great deal to be able to pick up the work of a former surveyor where it was left off, and to be able to carry it forward without rctracing from the beginning. The purpose of this paper is to describe the survey-note system of a mine now under my direction, in which underground surveys had to be relied upon entirely for the proper division of rich ore-bodies between neighbors, thereby placing a premium on accurate surveying and permanent records. In survey-work, it soon turns out that paper is the least item of expense, and that little is gained by trying to economize note-book space. For many purposes it is best to record notes on cards or loose-leaves, which may be left in the office at the end of the day's work, and need not be carried into the mine again, there to become smeared with grime and grease. With the loose-leaf or card system, all notes relating to the same local-

Jan 1, 1911

IN international affairs, the great event of June was the meeting of representative bankers at Paris -for consideration of the arrangement of a large loan to Germany. The conference dissolved in futility. Following this abortive conference, the delegates to the parley at the Hague assembled there on June 15. America is not represented at the Hague, any more than at Genoa. The British view the conference seriously and have Leslie Urquhart, the highest authority on Russia, attending in an official capacity. The Irish had their election and voted by strong majority in favor of the treaty with Great Britain, which was happy, but the general situation in Ireland is miserable. In China there were spectacular military and political events. Economically, Japan was in trouble. Conditions are becoming better in India, although no yet settled. Egypt has troubles still. Australia has a better chance for welfare, following the overthrow of its labor govern-ment early in April last. In Europe it is hard to discern any improvement except in Great Britain. Business in Great Britain has been slowly widening. The future of Great Britain, which is chiefly an in-dustrial country, depends on finding employment for its, 1,750,000 idle men. Personalities figured largely in June. Lenin's health was represented as having failed so that the govern-ment of Russia has had to be-turned over to a trium-virate. All of this has been denied. It is clear that some. mighty events are transpiring there. The assassination of Doctor Rathenau in Germany is probably also an occurrence of portent. The murder of Field Marshal Wilson, in London, tended to in-crease anger in England against the Irish. In the United. States the attention of Congress was concentrated on the soldier bonus, the tariff bill and the subsidy for shipping. All of these projects are economically bad and are of the same nature, viz., the allotment of a bounty to some classes of people, without consideration to the general national interest and welfare.

Jan 7, 1922

The authors have done a very thorough job in analyzing the factors affecting turndown sulfur performance at Inland's No. 4 B.O.F. While many of the results are not unexpected, it is helpful I am sure to have quantified many of the relationships that the operators rely upon daily. On the other hand, however, the results shown for ladle skimming are very surprising. I do not doubt the statistical relationship shown but I feel, based on our experience at Youngstown, that some other parameter has been ignored in the data on ladle skimming. It was our experience that by skimming our hot metal transfer ladle we could reduce our lime consumption by eleven percent while obtaining sulfur removal comparable to that shown by the authors. I would like the authors comment of similar adjustments on the lime charge that were made on skimmed heats at Inland. If not, it would seem that one could gain more desulfurization in the B.O.F. by raising the hot metal manganese than by installing a skimmer. The author's state that no comparisons are valid between the data sets for the two time periods involved because of the difference in the consumption of No. 2 Bundles. I feel this in fact is one of the important conclusions to be drawn from the paper, as there seems to be approximately a 10-20 percent difference in percent of heats that are under 0.020 percent sulfur for similar conditions, which is an extremely important difference with today's demands for low sulfur. I would like the author's comments on the difference in the amount of 82 bundles consumed. Along this same line I was quite surprised by the relatively low number of heats that had a first turn down of 0.020 percent sulfur or less. Also rather disconcerting are the conditions necessary to achieve a first turn of 0.020 percent sulfur, 50 - 60 percent of the time, as required by today's specifications. It is a problem which we are well aware of, but the numbers are still shocking.

Jan 1, 1972

By C. C. Hagenbuch

Machine loading of coal into mine cars is increasing rapidly. Particular reasons for its use frequently apply to certain localities, but in general, it is profitable to install mechanical coal-loading equipment: (I) when existing hand-loading contract rates prevent further cost reduction; (2) when the height of the coal bed requires that either top or bottom must be taken to place cars in rooms; (3) when labor shortage or limited house-plant capacity prevents the production of desired tonnage ; (4) when tonnage requirements are in excess of possible hand-loaded production from developed areas; (5) when working places are scattered and it is possible to concentrate production, and therefore supervision, by the installation of mechanical equipment; (6) when rapid development is essential. Having decided to install loading equipment, the problem then arises as to what type is best adapted for a particular mine or coal bed, the choice lying between mobile track equipment, pit-car loaders, scrapers, shaker conveyors, belt conveyors and drag conveyors. MajoR FactoRs Influencing Choice of Equipment In determining the type of equipment to be used, the following major factors must be studied: Grades.—Adverse grades, while permitting other types of loading equipment to work successfully, may prevent the success of a shaker conveyor installation. Thickness of Bed.—The thickness of coal governs the choice of equipment. A machine that requires 5 ft. of head room should not be selected for a 3-ft. bed where otherwise it would be unnecessary either to brush top or to lift bottom. Nature of Pavement.—Soft or scaly bottoms are unsuitable for the use of any type of digging loader, shaker conveyors or scraper loaders. nigging loaders and scraper loaders scale the bottom, mixing it with the coal and causing preparation difficulties; shaker-conveyor drives frequently work themselves loose, destroying the conveyor alignment and creating maintenance problems. Nature of Roof.—With any type of loading machine, it is policy to obtain the maximum possible tonnage per move per set-up. This must

Jan 1, 1931

By J. E. Strongman

This paper describes a system dynamics model of the international copper system. The development of the model is described regarding the questions it was designed to address, model boundary, major sectors and actors, the availability of data, the copper life cycle, and major supply and demand dynamics. A base forecast is presented describing future supply, demand, capacity, prices, trade flows, scrap flows and capital expenditures from 1976-1990 for the major producing and consuming market economy blocs.

Jan 1, 1977

By R. L. Fleischer, R. S. Davis

BICRYSTAL specimens grown from the melt have been used extensively for investigations of the influence of grain boundaries on plastic deformation. The bicrystals are usually of predetermined orientation prepared by seeded growth from the melt in milled graphite boats. This technique has been described in detail by Chalmers.' Since the direction that the grain boundary follows during growth is affected by both thermal conditions and crystallography, a difficulty arises in maintaining the grain boundary position constant along the length of the specimen. This problem is particularly

Jan 1, 1960

By K. A. Lambert

In the Anthracite Region there are considerable areas where the original mining was done 50 or more years ago. In this original mining, the pillars that were left proved inadequate in size for the support of the roof, which has since collapsed as a result of squeezes, and completely filled the original openings. In an endeavor to recover the coal which remains in the pillars in such areas, the reopening cost for development, as well as for pillar recovery, has been excessive in many instances. Various methods have been tried out with a view to lowering the cost, in order that the greatest possible percentage of recovery of the reserve tonnage may be realized economically. Ordinary hand mining necessitates the driving of development road 10 ft. wide in the clear between timber legs, with 6 ft. of clearance over the rail to accommodate mine cars; collars or crossbars on the timber sets have been difficult to maintain in these openings in the heavily caved condition, especially in beds where the overburden is great,. Numerous failures have occurred on these development road timbers because of roof movement resulting from removal of pillars. The actual removal of pillars from this development work has been costly because full-width openings for transporting mine cars to the face have to be maintained by cleaning caved material from alongside the pillars, or skipping up along the pillars where pillars of sufficient width are found. Shaker-chute Methods A method of developing such caved conditions and recovering pillars tributary to this development, utilizing shaker chutes, is being tried out with considerable success at Loree colliery. An outline of the chute and apparatus is shown in Fig. 1, which indicates the location of pillars and caved material. The cost of both labor and material required in the recovery of such coal is considerably less than by ordinary hand methods. In order to try out this method of mining a location was chosen where a tightly caved area had been developed by ordinary hand methods to within 300 ft. of the property line. The original bed height was 12 ft., with an overburden of 325 ft., but on account of the squeezes which

Jan 1, 1931

By E. I. Salkovitz, F. W. von Batchelder

AS Slawson1 and others have already shown, from a geometrical view twinning in the diamond structure may be considered as a reflection across a (111) plane or as a reflection across a (112) plane. An analysis by Ellis and Treuting2 showed that the twinning plane must be the (111) plane, but that a twin might have lateral boundaries along (112) planes. Earlier Slawson1 and Ellis3 had shown that only (111) twinning was present in diamond and germanium respectively. Since an ingot of silicon, 1 in. in diam and 1 1/2 in. long, prepared from Dupont silicon to which 0.2 pct Be had been added was available, it was examined for twinning. The ingot had been cooled slowly from the bottom. A section 1/16 in. thick was ground off from the bottom and then the ingot was sliced vertically through the center. Spectrographic analysis indicated only faint traces of iron and silver, in addition to the beryllium. The sample was first etched with a hot solution of 10 pct NaOH in water.and photographed. Back-reflection Laue patterns were made of the vertical and horizontal sections in the regions designated in Fig. 1. Orientations were obtained for each twin using the Greninger technique. Several regions of the same orientation were found; thus regions A and K were identical, similarly N and P, and C, G, J, and L. Knowing the angles between the traces of the twinning plane on the surface and the specimen axis, the indices of the twinning plane were deduced. In all cases the twinning plane was found to be (111); lateral boundaries, however, were found which were (112) such as the one indicated in Fig. 1. Therefore, as in the case of diamond1 and germanium' only (111) twinning occurs in silicon. We wish to thank Mr. Hino for the use of the ingot as well as for its metallographic preparation. References 1C. B. Slawson: American Mineralogist (1950) 35, p. 193. 2 W. C. Ellis and R. C. Treuting: Trans. AIME (1951) 191, p. 53; Journal of Metals (January 1951). 3W. C. Ellis: Trans. AIME (1950) 188, p. 886; Journal of Metals (June 1950).

Jan 1, 1953

By John M. Dealy, Robert D. Pehlke

This note presents a summary of the available literature on activity coefficients at infinite dilution in binary metallic solutions, Table I. These data should prove useful in not only examining the therm-odynamic properties of binary metallic solutions, but also in predicting the activity of a component in a complex alloy. The relationship proposed by wagner1 for expressing the activity coefficient in dilute solution is of the form:

Jan 1, 1963

"Only the coal of the Sunnyside district in Carbon County is coked. Two companies, the Utah Fuel Company and the Columbia Steel Corporation, operating adjoining mines at Sunnyside and Columbia, produce coke.The Utah Fuel Company has 819 beehive coke ovens at Sunnyside. Only 350 ovens are being operated at the present time, largely because the smelters which had been using Sunnyside coke changed their equipment from blast furnaces to reverberatory furnaces.The Columbia Steel Corporation operates a plant of 33 Koppers type by-product coke ovens at Ironton, near Provo. About 800 tons of coal are used per day to produce coke for the company's iron blast furnace plant pie ovens produce about 400 tons of coke, 12,000,000 cubic feet of gas, 9,000 gallons of coal tar, 3,000 gallons of benzol and several tons of ammonia sulphate per day.The total coke production for the State from the earliest output of record in 1880 until June 30, 1924, is 5,947,714 tons."

Jan 1, 1925

By M. Van Siclen

THE outstanding fact in connection with dust disease in the United States at present is the growing recognition of its seriousness by state officials and by the more progressive operators of mining, metallurgical and allied industrial plants. The same may perhaps be said of labor in some of its better organized centers, but the average independent non-union workman continues, as of yore, to suffer the toll of disability and even of death from dust inhalation without realization of the source of his ill-being. Progress in the betterment of the handling of sufferers from dust disease and of the conditions creating dust hazards in mining and allied industries is pursuing a course similar to that of the now widespread campaign against accidents, in which the risk is more obvious, more severe, and was naturally recognized sooner. The coming on of dust disease is generally relatively slow and its immediate effects not infre-quently masked by or attributed to other diseases. Marked exceptions to this general rule have occurred in districts where the dust is particularly pernicious, such as the Rand and Joplin; yet such exceptions, unhappy in themselves, opened the eyes of medical men, and of those in other localities charged with the responsibility for the welfare of industry, to the much more widespread if less spectacular hazard existing from the inhalation of dust in all rock-excavating operations and all industrial operations creating inorganic dust, whether it be crushing and grinding, sand-blast-ing, granite-cutting, or what not. Advancement to date in the United States in prevention and treat-ment has been slow, yet the record shows that quantitative methods for determining the degree of hazard and means for decreasing it were being developed as far back as 25 years ago; and that more rapid progress may be looked for from now on. In 1908, in this country, F. L Hoffman?(1) discussed the mortality from consumption in dusty trades, especially brass foundries; and in 1913 E. R. Hayhurst(2) described the effects of inhalation

Jan 1, 1933

By H. E. Strauss

The short-time tensile-strength test, while it has not attained the practical importance of the creep test at elevated temperatures, has the advantage of being rapid and is satisfactory for determining relatire strengths. For platinum and its alloys, which frequently are used at high temperatures under ill-defined conditions, the short-time test provides useful data that aid in the selection of the most promising alloy for each use. Measurements have been made upon 13 alloys, using wire 0.0031 in. in diameter, the choice of alloys and of wire size being determined by the requirements of a practical problem. Later the measurements were extended to higher temperatures by the use of heavier wire, 0.010 in. in diameter. Apparatus The use of fine wire made the necessary equipment very simple, since no effort was made to measure the elongation. A small platinum-wound horizontal furnace was used, 1/2 in. in internal diameter by 1 ft. long, with the wire threaded through it. The wire, clamped at one end while the other ran over a ball-bearing pulley, of a total length of 29 in., was loaded directly by running sea sand into an attached basket, making the rate of loading and not of elongation constant. The sand flowed from a funnel, under a head of 3 in., into the basket 3 in. below the orifice, at the rate of 170 grams per minute. Pulley friction and bending resistance of the wire as well as the force of impact of the sand could be neglected, being 3 grams and 0.5 grams, respectively. Furnace temperature was uniform within ±5° C. over a length of 3 in., although a drift with time occurred, the largest amount being 20" C. No provision was necessary for a controlled atmosphere. In making the measurements, the furnace was brought to equilibrium before being used, and the temperature was measured with a platinum platinum-10 per cent rhodium thermocouple and a high-resistance pyrometer before and after all the tests at one temperature. The wire sample, after being threaded through the furnace and attached to the

Jan 1, 1940

By H. E. Strauss

The short-time tensile-strength test, while it has not attained the practical importance of the creep test at elevated temperatures, has the advantage of being rapid and is satisfactory for determining relatire strengths. For platinum and its alloys, which frequently are used at high temperatures under ill-defined conditions, the short-time test provides useful data that aid in the selection of the most promising alloy for each use. Measurements have been made upon 13 alloys, using wire 0.0031 in. in diameter, the choice of alloys and of wire size being determined by the requirements of a practical problem. Later the measurements were extended to higher temperatures by the use of heavier wire, 0.010 in. in diameter. Apparatus The use of fine wire made the necessary equipment very simple, since no effort was made to measure the elongation. A small platinum-wound horizontal furnace was used, 1/2 in. in internal diameter by 1 ft. long, with the wire threaded through it. The wire, clamped at one end while the other ran over a ball-bearing pulley, of a total length of 29 in., was loaded directly by running sea sand into an attached basket, making the rate of loading and not of elongation constant. The sand flowed from a funnel, under a head of 3 in., into the basket 3 in. below the orifice, at the rate of 170 grams per minute. Pulley friction and bending resistance of the wire as well as the force of impact of the sand could be neglected, being 3 grams and 0.5 grams, respectively. Furnace temperature was uniform within ±5° C. over a length of 3 in., although a drift with time occurred, the largest amount being 20" C. No provision was necessary for a controlled atmosphere. In making the measurements, the furnace was brought to equilibrium before being used, and the temperature was measured with a platinum platinum-10 per cent rhodium thermocouple and a high-resistance pyrometer before and after all the tests at one temperature. The wire sample, after being threaded through the furnace and attached to the

Jan 1, 1940

By Gary E. McIntosh

This paper will discuss a US Bureau of Mines project designed to assess and predict the impacts which surface coal mining will have on the regional shallow groundwater system in the Powder River Basin. The primary objective will be met through the accomplishment of the following: (1) The design and establishment of a regional network for monitoring shallow groundwater systems in the basin; (2) monitoring the direction and rate of flow, water quality, and aquifer characteristics of the shallow groundwater systems; and (3) development of a regional groundwater simulation model, with appurtenant subroutines to determine local effects.

Jan 4, 1979

By George J. Conroy, James H. Green

Results of a long-term program of electrical parameter measurement in underground coal mine working sections, performed by The Pennsylvania State University under US Bureau of Mines (USBM) sponsorship, are utilized as the basis for an analysis of the electrical energy requirements during operation. A model section is hypothesized, developed from the average or most representative characteristics as determined from tabulations of the measurements. Performance factors of the model section's machine complement are then analyzed, particularly with regard to the energy required per ton of raw coal cut and delivered from the section. Results are given in kilowatt -hours per ton.

Jan 1, 1980

By Elburt F. Osborn

The phrase "Clean Synthetic Fluid Fuels From Coal," implies that it is possible to obtain adequate and dependable supplies of fuel without sacrificing the quality of our air, water, and land. Because of the long lead times needed to develop technical feasibility, into commercial reality, however, vigorous efforts must be made now in order to do it. The available options for clean fuels include many exotic sources, like solar and geothermal power, fuel cells, and thermionic and thermoelectric systems. To solve the energy crisis, however, we have three basic energy criteria-abundance, reliability, and commercial availability by 1985. Only processes based on converting coal and oil shale to clean, synthetic fluid fuels can meet all three.

Jan 9, 1974

By Fred McConnell

FROM beginning to end, the processes of coal stripping are of great interest. From the time the prospector enters upon the property to examine it and to prove it, until the coal is loaded into railroad cars, every step must be taken with careful thought and planning. In proving the merits of a prospective property, an examination and computation of the overburden is of almost equal importance to the determination of the extent and quality of the coal bed itself. Is the overburden hard, and will it require drilling and shooting? How many yards of it will have to be handled to produce a ton of coal? Will it remain in place when .put in the spoil bank, or will it spread and run back into the pit? Are the drainage problems serious, and what will it cost to handle the water? Does the coal have bad dips, and what will be the grades and curvatures for haulage? These are a few of the physical problems that confront the prospector, and they can be ascertained only by adequate and careful drilling and engineering of the property to be considered. The engineer is an ever-present necessity, not only in the prospecting but in the daily operation of the property after it has' been approved and developed. The first step in operation after the location of the tipple is the contouring of the surface to be stripped and the laying out of the pits for operation, having in view again adequate room for spoil, drainage, haulage and other problems. If the overburden is hard, as much of it is in the larger stripping areas, it must be drilled for shooting with churn or well drills, the holes continuing from the surface down to or near the coal bed. The location of these holes should be made, and marked with stakes, by the engineer, acting in conjunction with the shooting foreman. The usual practice is to drill holes 6 in. in diameter, although the present tendency is to increase the diameter of these holes so that they will hold, without springing, a larger charge of explosive. With the use of the old method of shooting, the holes were sprung or chambered several times with charges of dynamite, and in the cavity thus made, the explosive was placed, largely at the bottom of the hole; but with the use of liquid oxygen as an explosive, and with the later

Jan 1, 1931

By W. E. Horst

John Dasher (Central Research Laboratory, Crucible Steel Co. of America, Pittsburgh. Pa.)— Getting spodumene to float quickly and cleanly can be a problem. The author has presented an excellent account of a valid and useful approach to the scale-up of such problem floats. This indicated advantages for doubling retention time, i.e., buying another set of flotation cells. The author states that 21 pct of the spodumene floated in 2 min in the laboratory cell, that the grade of the rougher was about 75 pct spodumene, and that the final tailing contained 4 to 12 pct spodumene in different sizes with the present cells and 1 to 9 pct spodumene with twice as many cells. About 20 years ago, this writer obtained in the laboratory the flotation of over 90 pct of this spodumene in a King's Mountain sample in 1 min at a grade of 90 pct spodumene in the rougher and a final tailing that contained only 1 pct spodumene. The methods of Norman, Ralston," and Gieseke' were used, which teach that spodumene floats quickly and cleanly if its surfaces have been properly conditioned chemically and/or mechanically prior to flotation. Although feed preparation is not discussed, the results reported indicate that it is inadequate. This writer suggests that improvements in this area might be more effective than doubling the number of cells. W. E. Horst (author's reply)—Dasher's comments are appreciated by the author and require some clarification. He suggests that improved spodumene flotation performance may be obtained by feed preparation techniques rather than increased retention time in flotation. Certainly flotation performance is dependent on feed preparation and this is an important feature in the flotation process. It is true that certain types of spodumene ores, particularly weathered ores, require more complicated feed preparation processing than clean ores to achieve the desired flotation results. It was not implied that current feed preparation techniques are the same as experienced during the scale-up investigations. Although discussion of feed preparation was omitted from the article on scale-up relationships, the important feature was that pre-treatment processing was the same for each level of operation investigated— laboratory, pilot plant, and plant scale. Under these similar conditions large differences existed in recovery for comparable time intervals in each scale of operation. It is highly probable that feed preparation techniques could be modified and thereby increase the flotation rate for each scale or all scales of operation discussed. However, modifications would have to be justified on an economic basis.

Jan 1, 1960

By James E. McNulty

Coal reserve estimates are prepared using a simple equation: the product of area, bed thickness, density and recovery factors. Each of these elements involves a degree of risk based on certain assumptions. Reserve area, thickness and density rely on certain physical data whose accuracy, reliability and sufficiency may be problematical. Estimates of recovery factors for mining and coal preparation are often subjective. Most reserve estimates assume, sometimes incorrectly, that the subject reserves will be completely extracted. The principle that certain coal resources are reserves, if they can be considered economically recoverable at the time of determination, needs to be reexamined in the light of recent market cycles. Reserve estimating requires the exercise of judgments, the validity of which reflect the qualifications, experience and objectivity of the estimator.

Jan 1, 1985

By H. B. Bailey

SiNcE the gypsum deposits of Nova Scotia have been operated on a large-tonnage basis, it has become increasingly necessary that more study be given to the geological relation of gypsum to anhydrite. It was while attempting to work out some definite system of quarry operation for several operators that the factors relating to hydration as given in this paper became apparent. For convenience the words "the formation" are used to mean anhydrite and gypsum taken together as one bed geologically and forming a distinct unit from the rocks below or above. Also, the word "block" is used geologically to define a portion of the formation that is cut apart and separated by erosion from other portions. The formation is part of the Lower Carboniferous, the remainder of which is made up of red shales and shaly sandstones, coarse red conglomerates and limestones. Overlying the Lower Carboniferous are the even-bedded gray sandstones of the coal measures. To a large extent these sandstones have been eroded from above the formation and the usual cover is clay and unconsolidated sediments. The position of the limestone member which immediately underlies the formation usually furnishes the key to the general structure. Being harder, and subject to less erosion, it has a wider spread than the'formation, and measures for dip read on it have a value which can not be applied to dips taken on gypsum or anhydrite. This limestone usually is not more than 25 ft. deep, but it has a remarkable tenacity—one would almost say elasticity—under strain of earth movements. In many cases it stands as a barrier to the erosion which otherwise would have destroyed completely the remaining block of the formation. No bedded limestone is found within the formation except in narrow seams close to the bottom and in short irregular masses in highly disturbed strata where it has been caught up by fault action. This paper is not concerned with the general theories of original deposition and no opinion is expressed as to whether gypsum or anhydrite was first deposited from evaporating sea water. For purposes of study, and as an observed fact, except in the few cases where there has been extreme disturbance, a block of the formation is regarded as a block of anhydrite which has become partly hydrated into gypsum. 177

Jan 1, 1931