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Jan 1, 1892

There were present eleven Directors, the Institute's Legal Counsel, the Secretary, the Assistant Secretary, and twenty-three guests. The Report of the Committee on Nominations (listed elsewhere) was presented and ordered to take the statutory course. The appointment of a Committee on Mine Taxation was approved. An Advertising Manager was appointed. E. G. Spilsbury and A. S. Dwight were appointed as representatives of this Institute on the Franco-American Engineering Committee. The Transactions were presented to the University of Louvain, and the monthly Bulletin to the French Technical Index. Permission was given to publish in full the argument of William H. Shockley on simplified spelling. A committee was appointed to have charge of the publication of the Raymond Memorial Volume. There were elected 70 members, 15 associates, and 1 junior associate. Three members were reinstated and the resignations of two were ac-cepted. The clues of 10 members who had been in active service with the allied armies were remitted. An extension of time for the payment of dues was granted to the 11 members.

Jan 12, 1919

By R. S. Shrode, R. F. Bunting

Transportation is one of several important increments in the total market cost of most commodities. On a national average it has been reported that transportation accounts for about 25% of the total cost of a product at the market place. And industrial minerals are no exception. In fact, the proportionate cost frequently exceeds the 25% average. Further, it may actually determine the economic value of a deposit. Transportation possibly may be thought of as a specialized subject, of concern only to a traffic manager and of only nominal interest to the mining engineer, the geologist or other technically oriented member of a mineral producers' staff. However, in the industrial minerals field, interest is not commonly confined to exploration, development, production or marketing, but is in contrast an overlapping one. In a very real sense this broad area of interest in the total economics of the business is the specialty of the industrial minerals man. And transportation is a vital part of the total picture.

Jan 1, 1970

By Barry N. Whittaker

INTRODUCTION Considerable progress has been achieved with long- wall mining in recent years especially in enabling increased rates and levels of output to be gained, higher standards of safety and increased usage of advanced technological developments. Longwall mining also has major long term advantages, prominent amongst which is general minimisation of the effects of pillars and room intersections giving rise to future instability problems as can be the case with room and pillar mining operations. The fact that longwall mining is not presently limited by depth below surface inclination of seams or thickness of seam to be worked strengthens its position as the most popular underground mining method for extracting coal seams in Europe. Its wider application in North America and Australia can give rise to significant economic benefits coupled with higher levels of safety and recovery of coal. This present paper reviews recent progress achieved and draws attention to the more important factors influencing longwall mine design and layout. LONGWALL STRATA PRESSURE ABUTMENTS A longwall gives rise to major redistribution of strata pressures. The roof behind a longwall is normally allowed to cave and permit subsidence of the overlying strata and eventually giving rise to a trough depression at the surface. Consequently, reestablishment of strata loading within the caved region behind the longwall depends upon effective caving and subsequent recompaction. This requires sufficient depth pressure and/or adequate width of extraction in relation to the depth to achieve breaking of overlying roof beds necessary to reload the extracted region. Figure 1 shows results of an analysis carried out by Whittaker and Singh (1979) indicating the pattern of redistribution of vertical stress around a longwall in the plane of the seam. The analysis represents the average depth of longwall working in the UK, and was performed using a stress balance assumption of compatibility before and after mining. The main stress abutments are indicated by (1) the front abutment strata pressure zone which travels with the longwall, and (2) the flank abutment strata pressure zone which

Jan 1, 1982

By George H. K. Schenck

The greatest difficulty in choosing solutions to environmental problems ill a free market economy (such as ours) stems from two factors: adverse effects of pollution are largely external to the producer, and expenditures made that improve the environment result in benefits that are free to all, These two factors are sufficient to explain why the solution to many environmental problems is to be found in public action. Such action is most likely to be economic- ally efficient if it can be carried out so that industry retains the freedom to make decisions based on the free market. Two examples-a zoned discharge fee and innovation of recycling systems-illustrate the type of changes in the mineral industry that would lead to an improved environment. The first requires that ownership of the relevant public resources be vested in control agencies. The second indicates that profit opportunities existing in solid waste recycling should facilitate innovation. Both concepts can reduce environmental loadings but will require imaginative thought from persons in the mineral industries.

Jan 1, 1971

By Howard M. Graff, Sidney C. Bouwer

The economics of mining has traditionally been viewed quite apart from the economics of blast furnace operations. It was realized, of course, that blast furnaces would operate best with good raw materials, but the shipping grade of ore, for example, was decided by a sort of collective bargaining process between the ore producers and the blast furnace operators. The mine operators had to keep their costs down, and were usually successful in convincing management that the ore in any particular deposit was endowed by nature with a certain iron content and that the mine grade could not be raised beyond a certain economic limit. The blast furnace operators would have liked a better grade, but as long as they were able to make a fairly good showing it was more or less accepted that they had to take the ore as it came. The mine operators were able to ship to the nation's blast furnaces thousands of tons of iron ore that would be completely unacceptable by present-day standards. As late as the early 1950's, the major steel companies were witnessing an actual decline in the iron content of their incoming ore supply as the mining companies mined progressively leaner material and upgraded it only enough to pass competitive market requirements

Jan 8, 1965

A severely technical article, however well written, can not be an agreeable form of literature. It suffers from the defects of its qualities. One defect is a congestion of language, due to a multiplicity of adjectival nouns. The sentences are packed with words of unpleasing sound, charged with complex ideas, crowding one another so closely that the phraseology moves like an ice-pack in Bering Sea or a log-drive in a river; the undercurrent of meaning may continue to move, but the surface is obstructed. This verbal congestion is made evident by ugly compoundings, many of which are adopted by the technical writer in the mistaken belief that they give directness to his statements. For example: A unanimously approved scheme "A scheme unanimously approved " The continuous temperature record "The continuous record of temperature " To stimulate interest in synthetic plant construction "To stimulate interest in the construction of synthetic plants " In smelters reverberatory-furnace firing with powdered coal has been practised for a decade. "In smelting, the firing of reverberatory furnaces with powdered coal has been practised for a decade." A tar consumption of one pound per ton "A consumption of tar at the rate of one pound per ton " A mechanical ventilating system

Jan 1, 1931

By William Kent

Mr. ASHBURNER's paper on the Classification and Composition of Pennsylvania Anthracites, read at this meeting, well shows the need of new and accurate determinations of the heating value of these coals. A similar need exists for the determination of the value of bituminous coals, since the variation in quality of the latter is greater than the variation in anthracites. The recent extensive use of liquid and gaseous fuels, " patent" fuels, tan-bark, and other refuse fuels, also makes a necessity fix some correct method of determining the relative values of each of these fuels. Mr. Ashburner has recommended that tests of coals should be undertaken by the Second Geological Survey of Pennsylvania, and Professor Dewey, as stated in Mr. Ashbnrner's paper, has suggested a plan for tests of American coals, by the Smithsonian Institution, for which an appropriation by Congress will be asked. It is to be hoped that if any extensive series of tests of coals is carried on under either Government or State auspices, the erroneous methods of test which were followed by Professor Johnson in 1842, and by Quartermaster-General Meigs in 1882, will not be adopted.* The first requisite in determining the heating-power of a fuel is proper apparatus, such as has not been used in any of the tests of American coals yet reported. In the hope that more accurate means may be used in future tests, the writer desires to call attention to an apparatus which he has designed for the purpose. Not having had opportunity for making a trial of it, nor even of having it criticised by others, he does not offer it as the best possible apparatus; but if it contains any points of value, and leads to the design of still more suitable devices by others, the object of the presentation of this paper will be accomplished. The tests by Professor Johnson and General Meigs were made by evaporating water into steam in ordinary steam-boilers. A steamboiler of ordinary construction is not a good apparatus for determining the heating power of a fuel, for the following reasons:

Jan 1, 1886

IN describing the mining and treatment of ore at the Broken Hill Proprietary mine E. J. Horwood, superintendent of mines, gave the following account of the development of flotation there. It was in 1902 that the recovery of zinc from the ore by flotation was hit upon. The former general man-ager, Mr. Delprat, directed our then research officer, Mr. Carmichael, to try boiling the tailing with salt cake of which there was a considerable tonnage left over from the leaching process. The idea was the possibility of dissolving the zinc. Carmichael made the. Experi-ment, but, rather discouraged, took the glass beaker down to the general manager's office, remarking that he could not get the stuff to settle. On showing the beaker to Mr. Delprat, the latter recognized the marked distinction between the black scum on the surface and the rest of the tailings, and exclaimed: "Why, this is the very thing we are after; the zinc is floating!" Patents were applied for at once, but later on it was found that another investigator, Potter, had already hit upon the idea of flotation. His patents, however, were so involved with other operations that his process was impracticable. Litigation followed, but in the end the B. H. P. paid the Potter Company a substantial sum as settlement. In the case of Carmichael's beaker, the acid in the salt cake acted on the small amount of carbonate present in the ore, producing CO. bubbles. Owing to the aversion of sulfide crystals to being wetted, the gas as generated attached itself to the zinc in in-creasing quantities until there was sufficient to buoy the zinc particle to the surface. This action went The next problem was to apply the principle on a commercial scale, and this involved much experiment and developmental work. Various kinds of sloping copper pans with gas jets below to maintain the tem-perature were first tried, but were found too slow and too costly in operation.

Jan 6, 1928

By AIME AIME

FOR the purpose of subsequent discussion let me reiterate certain points in my paper. The things we are certain of are that individuals differ in their accident liability, and that the bulk of accidents in any industrial group is sustained by comparatively few individuals; further, that this difference in liability cannot be wholly accounted for by differences of exposure, since some of the personal factors involving a high accident rate have already been measured in certain industrial groups.

Jan 1, 1929

By R. A. Pallanch

Sodium sulfite as a zinc retarding agent in the selective Hotation of complex lead-zinc sulfide ores was discovered by the writer in the summer of 1919 in the testing laboratory of the U. S. Smelting, Refining & Mining Co.'s gravity concentrator at Midvalc. Utah. It proved to be the first reagent to give consistently good results in the laboratory on the cornpanj's Bingham ore. In December, 1919, C. A Lemke, concentrator superintendent, recommended that a flotation unit be added to the existing gravity mill to handle the mill slimes, using sodium sulfite as the zinc depressant Owing to the poor lead and zinc markets and the unfavorable royalty schedules offered by the Minerals Separation Co., the project fell through at this time. In 1921, a number of laboratory tests were made at Midvale. on other ores, among them ore from the Sunnyside mine at Eureka, Chlo. Both sodium and calcium sulfites were used with succcss on this ore. Early in 1923, further tests were made at Eureka, shortly after the Sunnyside company had resumed operations after a two-year shutdown. AS a consequence sodium sulfite was given a trial in the mill. The results showcd sufficient improvement over previous work as to warrant continuous use of this reagent in the lead circuit Exeept for a week or so in 1926 and for several weeks in April, 1927, when sodium cyanide and zinc sulfate were given trial runs in this mill. sodium sulfite has been used ever sinee.. Sodium sulfite was chosen rather than the calcim sulfite brcauscl of its gre1ater sollubility, making it possitdr. to introduee the reagent as a solutiun. This Solution is introdueed into the Marry ball mills along with the original feed of ore,. The consumption of sodium sulfite in the Sunnyside mill varies from 1/4 to 12 lb per ton of ore, the smaller amount probably being nearer the average. In February, 1924, laboratory work at Midvale demonstratcd conclusivcly that good results could be obtaincd on the company's Bingham ore and on most of the custom ores tested by using sodiuin sulfite as the zinc depressant, xanthate as the lead enhancer in the lcad circuit, followed by copper sulfate and additional xanthate to float the zinc Sodium sulfide was used to float the iron pyrite after the lead and

Jan 1, 1928

By C. N. Savage

The drawing above shows clearly the disastrous effects of a slow-motion "landslide," or mass wasting. A danger to water supplies, homes, and roads, it can also put strip miners out of business. Read how and why it occurs, and some suggestions for prevention.

Jan 3, 1950

By Edward Nichols

These deposits, which are found in James County, Tennessee, differ both in their mode of occurrence and in their chemical constitution from any other ores belonging to the same geological horizon which are known to the writer. Taylor's Ridge, or White Oak Mountain, is a long monoclinal ridge, which starts from a point near the Tennessee River in Meigs County, and, following a southwwt .course, extends unbrokenly into Cherokee County, Alabama, where it finally disappears. It is made up of strata of the Upper Silurian rocks, which dip to the southeast. To the eastward of this ridge, which is generally several hundred feet high, are a series of low foothills or knobs, composed of Clinton shales carrying seams of fossiliferous hematites. In the neighborhoud of the East Tennessee, Virginia, and Georgia Railroad, where it crosses the ridges, considerable ore has been milred from these seams during the pst ten years. Most of the workings have been superficial, and the ores mined, with one exception,,carry a silicious and nod-calcareous gangue, and contain from fifty to sixty per ceut. of iron.

Jan 1, 1882

By S. Webster, M. Karmis, C. Haycocks

Mining any seam can seriously affect subsequent operations in coal seams both above and below the one being mined. The effect is often detrimental to the recovery, cost and safety of mining the subsequent seams. This paper describes the ground control mechanisms involved in mining through a passive subsided zone or all actively subsiding trough. Data were extracted from case studies, primarily from the Appalachia region, for construction of empirical models to predict interaction problems that can occur in overlying seams. Inner-burden thickness, innerburden lithology, percentage extraction, lower seam height, time and overburden were analyzed to determine their effect on upper seam damage. Magnitude of upper seam subsidence was incorporated, together with a broad classification of rock types, to predict the type and range of damage that can occur in the upper seam. Results are summarized in graphically and nomogram form for use in. engineering design.

Jan 1, 1984

By Edward C. Roper

Pegasus' Gold Ltd. operates two gold/silver heap leaching operations in the Little Rockies area of Montana. The Little Rockies has produced gold from underground operations on an intermittent basis from the 1880's to the early 1950's and from the open-pits on a continuous basis since 1979. Run-of-the-mine ore is drilled, blasted, sorted, loaded and hauled. The waste is dumped and compacted into 30 meter (100 foot) fills to be used for future leach pads. The leach pads have a central drain system and the impermeable membrane is constructed of bentonite and 30 mil PVC. The plants which have beenexpanded to 4900 Ipm (1300 gpm) capacity use the Merrill-Crowe process for gold and silver recovery. 4600 liters (1200 gpm) of the 9500 Ipm (2500 gpm) spray capacity is recycled through the old leach pads for upgrading before being processed. The gold/silver precipitate is smelted and the resultant dore' is shipped to a buyerhefiner. 1983 projected production is 2,177 kg (70,000 02s) of gold at a cost of less than $10/gm.

Jan 1, 1984

By Zdzislaw Specht

This paper discusses elementary laws pertaining to seismic reflection methods and presents a general and simple criterion for determining the direction of dipping of a reflection horizon from observational data of distance and time. The important development of practical geophysics and the successful results obtained in America, Germany, and other countries, caused introduction of geophysical methods of prospecting in Poland. Of all methods, seismic prospecting has proved most successful in the area of the Carpathian foreland, where new oil reserves are to be expected. Because of the great depth of the sedimentary column in that area, ranging sometimes over 2000 meters, it was obvious that only the seismic reflection method could give reliable information regarding the structural features of these strata at such a depth. During the experimental surveys it appeared that the complicated geological conditions of that area do not always allow prediction of the depth and the angle of dipping of reflecting horizons, and for that reason information about the inclination of a given horizon has great importance in the determination of subsurface structure. Therefore the problem arises of obtaining from seismic reflection data reliable information as to the direction of dipping of reflecting strata, without any previous knowledge of the average velocity and depth of geologic horizons under consideration. Reflection Seismograms The earth, being a nonhomogeneous medium, is composed of a series of layers, which differ from each other in their physical properties, particularly in their elastic coefficients. These variations in elasticity are the cause of refraction and reflection of a seismic wave. Under the simple but only approximately correct assumption of the straight-line path or an elementary elastic disturbance, the phenomena mentioned

Jan 1, 1940

By Zdzislaw Specht

This paper discusses elementary laws pertaining to seismic reflection methods and presents a general and simple criterion for determining the direction of dipping of a reflection horizon from observational data of distance and time. The important development of practical geophysics and the successful results obtained in America, Germany, and other countries, caused introduction of geophysical methods of prospecting in Poland. Of all methods, seismic prospecting has proved most successful in the area of the Carpathian foreland, where new oil reserves are to be expected. Because of the great depth of the sedimentary column in that area, ranging sometimes over 2000 meters, it was obvious that only the seismic reflection method could give reliable information regarding the structural features of these strata at such a depth. During the experimental surveys it appeared that the complicated geological conditions of that area do not always allow prediction of the depth and the angle of dipping of reflecting horizons, and for that reason information about the inclination of a given horizon has great importance in the determination of subsurface structure. Therefore the problem arises of obtaining from seismic reflection data reliable information as to the direction of dipping of reflecting strata, without any previous knowledge of the average velocity and depth of geologic horizons under consideration. Reflection Seismograms The earth, being a nonhomogeneous medium, is composed of a series of layers, which differ from each other in their physical properties, particularly in their elastic coefficients. These variations in elasticity are the cause of refraction and reflection of a seismic wave. Under the simple but only approximately correct assumption of the straight-line path or an elementary elastic disturbance, the phenomena mentioned

Jan 1, 1940

By H. A. Gardner

THE principal use of barium sulphate is as an inert paint pigment.. For this purpose, the ground material is used both in its natural and in its artificial forms. Probably the largest amount is used in the production of a chemically precipitated pigment called lithopone which consists of 70 parts of barium sulphate and 30 parts of zinc sulphide. An enormous tonnage-of this pigment is at the present time being used in the manufacture of interior flat wall paints of the oil type, such paints having almost entirely supplanted the use of corroded white lead which was at one time used for interior painting. The more dense nature, lower price and sanitary value of lithopone was responsible for this change. Lithopone is, moreover, used to a large extent in the manufacture of oil cloth, shade cloth and linoleum. Its whiteness makes it of particular value for this purpose. Barium sulphate is also used of itself in admixture with other pigments in the manufacture of prepared paints. The chemically precipitated form of barium sulphate, which is generally called blanc fixe, is also used for this purpose. Much controversy has raged in the paint world over the question of inert pigments such as barytes, silica, asbestine and china clay. These pigments are probably called inert because they have no chemical action upon the linseed oil in which they are ground to produce paints, and on account of the fact that they become transparent in oil. It is well known that in the manufacture of paints, opaque white pigments, such as basic carbonate white lead, basic sulphate white lead, zinc oxide etc., are generally used as the grinding base. These base pigments, when ground in oil, react therewith to some slight extent, and they produce white paints which have excellent biding or obscuring value. The inert pigments so-called, when ground in oil and spread out into a thin film, form transparent coatings which have no hiding power. It has been contended, therefore, that the use of barytes or similar inert pigments in paints is resorted to simply for the purpose of cheapening the cost of the product.

Jan 9, 1914

Dimitri Konstantinovitch Tschernoff, was horn in Petrograd, Russia, on Nov. 1, 1839, and died in Yalta (Crimea) in the south of Russia, on Jan. 2, 1921. He obtained his early education in the Russian Gymnasium, corresponding to the American high school, and in the Technologic Institute. On graduation from this Institute in 1858, he was engaged as a professor of geometry and algebra and later became a librarian and superintendent of the museum in the same Institute. He also attended lectures in the mathematical physics section at the Univrrsity of Petrograd from 1859 to 1862. In 1866, Professor Tschernoff left the Technologic Institute and entered the employ of the Obouchoff steel plant, founded in 1863 for the manufacture of guns. Here he did his most important work on the heat treatment of steel, its crystallization and metallography. In 1880, he left the Obouchoff plant and went to the south of European Russia, where he discovered and developed some rock-salt mines. This enterprise brought him a rather large fortune. In 1884, he returned to Petrograd and during the next four years held several prominent positions in government departments. In 1899, he became professor of metallurgy in the Michael Artillery Academy, and retained that position until the time of the Russian Revolution. In 1902, Professor Tschernoff was elected an honorary member of the American Institute of Mining and Metallurgical Engineers. In September, 1917, Professor Tschernoff was sponding his vacation, as usual, in the city of Yalta (Crimea) in the south of Russia, with his wife and one of his daughters. The revolution progressed so rapidly that they were unable to return to Petrograd, and were compelled to stay in Yalta without provision for the winter season. Suffering from hunger. and lack of sufficient clothing, and deprived of his books, Tschernoff nevertheless continued his studies and gave a number of lectures on steel at the Polytechnic Institute. At the same time he worked hard on some. mathematical problems. His health broke down through long-continued under-nourishment. His works in the metallurgical field are well known to the students of metallurgy; good abstracts of his most important papers were published in Revue de Metallurgie (1915, pp. 829-882) in commemoration of his 75th birthday.

Jan 1, 1922

Dimitri Konstantinovitch Tschernoff, was horn in Petrograd, Russia, on Nov. 1, 1839, and died in Yalta (Crimea) in the south of Russia, on Jan. 2, 1921. He obtained his early education in the Russian Gymnasium, corresponding to the American high school, and in the Technologic Institute. On graduation from this Institute in 1858, he was engaged as a professor of geometry and algebra and later became a librarian and superintendent of the museum in the same Institute. He also attended lectures in the mathematical physics section at the Univrrsity of Petrograd from 1859 to 1862. In 1866, Professor Tschernoff left the Technologic Institute and entered the employ of the Obouchoff steel plant, founded in 1863 for the manufacture of guns. Here he did his most important work on the heat treatment of steel, its crystallization and metallography. In 1880, he left the Obouchoff plant and went to the south of European Russia, where he discovered and developed some rock-salt mines. This enterprise brought him a rather large fortune. In 1884, he returned to Petrograd and during the next four years held several prominent positions in government departments. In 1899, he became professor of metallurgy in the Michael Artillery Academy, and retained that position until the time of the Russian Revolution. In 1902, Professor Tschernoff was elected an honorary member of the American Institute of Mining and Metallurgical Engineers. In September, 1917, Professor Tschernoff was sponding his vacation, as usual, in the city of Yalta (Crimea) in the south of Russia, with his wife and one of his daughters. The revolution progressed so rapidly that they were unable to return to Petrograd, and were compelled to stay in Yalta without provision for the winter season. Suffering from hunger. and lack of sufficient clothing, and deprived of his books, Tschernoff nevertheless continued his studies and gave a number of lectures on steel at the Polytechnic Institute. At the same time he worked hard on some. mathematical problems. His health broke down through long-continued under-nourishment. His works in the metallurgical field are well known to the students of metallurgy; good abstracts of his most important papers were published in Revue de Metallurgie (1915, pp. 829-882) in commemoration of his 75th birthday.

Jan 1, 1922