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By William P. Blake

The metallic element Nickel, discovered by Cronstedt the mineralogist, in the year 1751, as a peculiar metal in kupfer-nickel, remained for a long time comparatively unknown in its true charac-

Jan 1, 1883

By James F. Lewis

The death of Josephus Flavius Holloway, for twenty-one years an active and beloved member, and twice a Vice-President, of the Institute, cannot be allowed to pass without some expression on the part of his brethren of mingled grief and gratitude—grief that we have lost his genial and inspiring presence ; gratitude that we have been privileged to know one who lived " To make the world within his reach Somewhat the better for his being, And gladder for his human speech." The present sketch of his career and character is offered as a sincere, though inadequate, expression of these feelings. Mr. Holloway's father, Joseph T. Holloway, born, in 1796, in Sunbury, Pa., and yielding in his youthful prime to the prevailing impulse of his generation, started alone, with knapsack

Jan 1, 1897

By J. F. Wolff

The iron formation of the Gogebic Range in northeastern Wisconsin and the northwestern part of the Upper Peninsula of Michigan, resembles that of the Mesabi Range in Minnesota very closely in lithologic character and the subdivisions and horizons that can be recognized. It contains numerous interbedded slaty layers and considerable intraformational conglomerate in certain horizons. In contrast to the flat dip of the Mesabi formation, the Gogebic dips steeply to the northwest at an average angle of about 70". It has a quartzite and siliceous slate foot wall and a hanging wall of conglomerate, graywacke and slate. The black and gray Tyler slate has been designated the hanging wall of the Gogebic iron formation in U. S. Geologicial Survey monographs, but between the true Tyler slate and the commercially important Gogebic iron formation, and apparently unconformably upon the latter, is a series 600 ft. or more thick of conglomerate, slate, graywacke, and cherty iron formation, the latter being of no commercial importance on the Gogebic Range as far as now known. This series is probably that described as the "Capps" on the eastern Gogebic by the Michigan Geological Survey. The Gogebic iron formation proper can be subdivided into three main horizons, a lower cherty and an upper cherty with a banded or slaty horizon between them, corresponding to the three lower horizons of the Mesabi. Several minor subdivisions can be made of these major ones. Orebodies occur in all three horizons of the Gogebic series and in some places ore is developed across practically the entire series. Dikes and Sills The Gogebic iron formation has been intruded most intricately by basic dikes and sills, most of the former pitching east but some pitching west. One very extensive sill is intruded near the base of the lower slaty or banded horizon, in the formation known locally as the Yale slates. One extensive bedding or strike fault is associated with this sill and a great many transverse faults occur at different places along the Range. The combination, or association, of steep dip, faults, dikes and sills has produced conditions very favorable for the development of orebodies through the leaching, oxidation, and consequent concentration effected

Jan 1, 1925

By Stanley M. Miller

The probabilistic nature of appropriate geologic variables can be included in analyzing the stability of potential slope failure modes. Random variables in the two-dimensional plane shear analysis of a specified structural discontinuity include the shear strength and waviness angle of the discontinuity and, in some cases, the rock mass density. Estimated probability density functions that describe these random variables are combined by Fourier analysis to produce an estimate of the safety factor probability density function, which appears to approximate a gamma distribution. The probability that sliding will occur along the specified structure is equal to the area under this density function where the safety factor is less than one.

Jan 1, 1982

By Ronald J. Roman, Craig Olsen

Alterations were performed on a previously developed heap leaching model representing sulfuric acid solution leaching of a malachite sandstone ore. The alterations were made in order to approach a more realistic solution to the leaching equations used in the model and to provide a means of obtaining a constant acid con- centration in the model' s simulated heap effluent solutions. This constant acid concentration is desired if the effluent solutions are to be treated in a solvent extraction-electrowinning plant. An economic study was made showing a use of the leaching model for an imaginary heap leach operation. The example illustrates a method of selecting heap leaching parameters if data are available on mining costs, dump costs, capital cost, etc. This was achieved using an incremental investment technique.

Jan 1, 1974

By C. A. Sobotowski, J. Eagan

Computer programs applicable to coal mining have been available for some time, especially in the academic sector. However, the computer has not routinely been applied to actual mining operations. This paper discusses how a computer system was set up as an important tool in mining design and decision making. The project was completed within the allotted timeframe of two months by taking advantage of existing technology. Key points include the selection of programs to meet the specified needs of the project, conversion of the programs to be compatible with a computer of a different manufacture, simplification of the data entry process, development of procedures for using these programs, and an explanation of how the reports generated from the programs were used for mine planning and decision making.

Jan 1, 1983

By Robert J. Willard

The scanning electron microscope (SEM), became commercially available in 1966. Embodying some unique features not provided by conventional electron microscopes, this new electron-optical instrument offers the scientific community a new way of observing the surfaces of materials. In rock mechanics research, the SEM should prove a useful basic tool in characterizing rock fracture on a very small scale and thus contribute to a better understanding of rock behavior at larger scales. This article presents one example of how the SEM is being applied to such research at the Twin Cities Mining Research Center operated by the U.S. Bureau of Mines in Minneapolis. This research center conducts theoretical and experimental studies on a broad range of mechanisms that induce disintegration by the application of energy to rock.1 Some of these studies are concerned with the relation of microstructure to rock behavior and are carried out mainly with the petrographic microscope. At the same time, however, the center recognizes that this relation must be studied through several orders of magnitude, from lattice-size units of rock-forming minerals to field-size rock units. The SEM fits this scheme by extending the capability of the petrographic microscope into smaller orders of magnitude. However, because its resolution is limited to about 200 A at 10,000x, the SEM is not capable of resolving lattice-size units, and hence a conventional electron microscope with a much greater resolution capability is necessary at this order of magnitude.

Jan 6, 1969

By A. Whillier

Methods are given for estimating heat flows into mining excavations of various types, with an example to illustrate how the refrigeration requirements are then determined after allowing for the cooling effects of the ventilation air.

Jan 1, 1981

By W. F. Boericke

The character of the Wisconsin orebodies must be clearly understood to appreciate the difficulties encountered in sampling and estimating them. Unlike the western vein deposits, they do not lie between regular walls, but form large, often highly irregular bodies, on a single floor in the so-called Galena limestone. The bottom of the ore is nearly always on the clay bed (a flat generally well-defined clay seam a few inches thick) which marks the junction of the base of the Galena lime and the top of the next formation, the Trenton lime. Above the clay bed, the orebodies make the unique pitch and flat formation described by Chamberlin.' Theoretically, we should find two pitches, one on either side of the top crevice, diverging as they go down, with the final flats a considerable distance apart on the clay bed. The area between, known locally as core ground, should thus constitute a single defined orebody, with the richer portions near the pitches and the leaner portion in the center of the core. Practically, we find few examples of this perfect orebody. Almost invariably one pitch is better defined than the other, and often the opposite pitch is marked only by a faint line of fracture showing stronger mineralization than the wall rock, or it may be totally lacking. But with an orebody of any size or richness, at least one strong pitch usually tends to follow an east-west trend, or a quartering course. Late mining developments in the rich New Diggings field indicate that these pitches often assume a horseshoe or crescent shape, the richer ore being in the heart of the crescent and the pitches showing less mineralization as they extend outwards. In the northern end of the field, on the contrary, the pitches maintain generally a consistent direction, and have been mined for thousands of feet from the shaft. The length of the orebody may be several thousand feet, the height varying from 10 to 60 ft. and the width from 60 to 250 ft. In fact, on the core side, there is no definite end to the ore. The mineralization simply gets thinner and thinner, and the limit of working depends on the cost sheet and the profit from the recovery.

Jan 1, 1923

By W. F. Boericke

The character of the Wisconsin orebodies must be clearly understood to appreciate the difficulties encountered in sampling and estimating them. Unlike the western vein deposits, they do not lie between regular walls, but form large, often highly irregular bodies, on a single floor in the so-called Galena limestone. The bottom of the ore is nearly always on the clay bed (a flat generally well-defined clay seam a few inches thick) which marks the junction of the base of the Galena lime and the top of the next formation, the Trenton lime. Above the clay bed, the orebodies make the unique pitch and flat formation described by Chamberlin.' Theoretically, we should find two pitches, one on either side of the top crevice, diverging as they go down, with the final flats a considerable distance apart on the clay bed. The area between, known locally as core ground, should thus constitute a single defined orebody, with the richer portions near the pitches and the leaner portion in the center of the core. Practically, we find few examples of this perfect orebody. Almost invariably one pitch is better defined than the other, and often the opposite pitch is marked only by a faint line of fracture showing stronger mineralization than the wall rock, or it may be totally lacking. But with an orebody of any size or richness, at least one strong pitch usually tends to follow an east-west trend, or a quartering course. Late mining developments in the rich New Diggings field indicate that these pitches often assume a horseshoe or crescent shape, the richer ore being in the heart of the crescent and the pitches showing less mineralization as they extend outwards. In the northern end of the field, on the contrary, the pitches maintain generally a consistent direction, and have been mined for thousands of feet from the shaft. The length of the orebody may be several thousand feet, the height varying from 10 to 60 ft. and the width from 60 to 250 ft. In fact, on the core side, there is no definite end to the ore. The mineralization simply gets thinner and thinner, and the limit of working depends on the cost sheet and the profit from the recovery.

Jan 1, 1923

By George Tryon, E. A. Barnard

The importance of the conservation of the waste heat contained in copper reverberatory furnace gases was realized very early by those in charge of operation at Anaconda. The first attempt to utilize it was in preheating the air used for combustion of the coal. This was done by forcing the air through ducts surrounding the flue-gas downtake and continued down beneath the furnace hearth to the firebox. Any small advantage gained by the heat transferred from the flue gases was more than offset by the losses sustained in cooling the hearth, therefore this process, after several trials, was soon discarded. It was first used at the Old Works as early as 1893 and again for a comparatively short time on the original furnaces at the Washoe smelter, or present works. Water-tube boilers came into general use very rapidly after 1890. Their adaptability for waste-heat steam generation, as well as the saving to be effected by the production of cheap steam from this source, was soon recognized. The first waste-heat boiler to be used in connection with a matte furnace at Anaconda was installed in September, 1900, at the "Old Lower Works." It consisted of a 100-hp. "Cook," vertical water-tube boiler. This boiler had 65 small perpendicular tubes arranged in concentric circles around a 10-in. tube in the center. These tubes were expanded into 4 ft. 4 in. inside diameter cylindrical steel top and bottom drums which served as the steam and mud drums respectively. This boiler was set in a cylindrical brick housing into which the furnace gases entered just above the mud drum and thence circulated upward around the tubes and steam drum to the stack. This installation proved unsatisfactory, presumably on account of difficulty with dust, and was soon abandoned. However, the possibilities for steam generation were undoubtedly encouraging for shortly afterwards (December, 1900) a 300-hp. Stirling boiler was installed, to be followed by two more in the spring of 1901. The choice of the Stirling type of boiler for application to copper reverberatory furnaces was particularly fortunate, as the arrangement of the tubes appears to combine to a great extent the maximum contact of the gases with the heating surfaces of the boiler and at the same time

Jan 1, 1934

By Kwang K. Koh, Nicholas C. Nahas, Richard C. Neavel

Sodium, a relatively abundant element in Illinois coal, is reported to cause fouling of utility boiler heat exchange surfaces. Distilled water extraction of 22 Illinois coal samples resulted in average removal of more than 50% of their included sodium. Chlorine was the dominant anion. Extraction rate conformed to Fick's law of diffusion. Extraction with hot water increased both the rate and maximum amount removed. A commercial-scale countercurrent staged process can be envisioned as technically feasible.

Jan 1, 1978

By Charles O. Thompson

In 1867 the city of Worcester walled in the Mill Brook for its main sewer. This stream, one of the important affluents of the Blackstone River, flows through the city in a southwestenly course from Salisbury Fond, and along its valley a considerable part of the heavy manufactories of the city are placed. At two points, a mile apart, a sufficient fall occurs to be turned to account for motive power, and at many points it was the right and practice of the riparian proprietors, prior to 1867, to use the water for steam and other manufacturing purposes. But the

Jan 1, 1881

By E. S. Bardwell, Roy H. Miller

During the period extending from May, 1922, to September, 1923, the copper-refining furnaces of the Great Falls Reduction Department of the Anaconda Copper Mining Co. at Great Falls, Mont., were operated exclusively with pulverized coal as fuel. The installation was made first as an experiment. It proved successful from the start and was abandoned solely because fuel oil from the Sunburst field became available at a price sufficiently low to be more desirable from an economic standpoint. The equipment required for pulverized coal has, however, been kept intact and is available for immediate use should the oil supply fail. Inasmuch as pulverized coal had been used on two large reverbera-tory smelting furnaces and was, at the time we were considering its application-to the copper-refining furnaces, being used on the Wedge furnaces roasting zinc concentrate for the electrolytic zinc plant, we were equipped with a coal-pulverizing plant of ample capacity to supply pulverized coal for the furnace refinery. The only problem was to devise suitable means for transporting pulverized coal from the pulverizer plant, located in the smelter building, to the refinery about 3000 ft. distant and about 150 ft. above the level of the pulverizer plant. When studying this installation, it should be borne in mind that the layout represents an adaptation suited to the existing conditions at this particular plant. The installation was entirely satisfactory and uniformly dependable but might be modified to advantage from an operating point of view if an entirely new installation were being planned. Fuel Supply The use of the local coals, high in ash and sulfur, was abandoned some time before coal-dust firing was attempted. Local coals from the Great Falls field carrying an average of 4 per cent. sulfur and 22 per cent, ash were used with fair success in the small furnaces in use prior to 1916. In the 250-ton furnaces, however, the time lost in grating and removing clinker from the fireboxes, as well as the difficulties incident to the high-sulfur content of the fuel, became serious and recourse was had to the

Jan 1, 1927

In 1803 the purchase of the immense territory called the province of Louisiana wm arranged between Thomas Jefferson, President of the United States, and Napoleon Bonaparte, First Consul of France. This central portion of what is now the United States was claimed in 1682 by the explorer Robert de La Salle for France, who continued to hold her title to the vast domain until 1762, when it passed by treaty to Spain, only to be retroceded to France in 1802, in consequence of Napoleon's military domination of Spain. Jefferson did not care to see New Orleans and its extensive hinterland pass into the hands of France. Spain did not matter so much; she was quiet and feeble, whereas France was restless and aggressive under Napoleon, who had dreams of founding a French colonial empire on the American continent. The expression of American feeling that Jefferson elicited came as a surprise to Napoleon, who concluded that a contest was not worth while, for his navy had been shattered by the English, and it was evident that only maritime supremacy could enable him to retain this trans-Atlantic possession; so he resolved to put it out of the grasp of England and at the same time replenish his military chest by selling Louisiana to the United States. The price was 60 million francs. By the terms of the Louisiana purchase a magnificent territory was added to the national domain; it covered more than a million square miles, or more than the total area of the United States at that time. Louisiana included the present States of Louisiana, Arkansas, Missouri, Kansas, Iowa, Nebraska, South Dakota, North Dakota, Wyoming, Montana, Oklahoma, with parts of Colorado, Idaho, and Minnesota; but

Jan 1, 1932

By R. H. Sweetser

There are so many conditions affecting blast-furnace results that it is hard to get satisfactory comparative data on the working of two furnaces, and much more difficult to get comparable results from the use of two entirely different fuels. The several advantages of charcoal over coke as a blast-furnace fuel have doubtless been apparent to many managers; but probably the conditions for comparative tests of the two were never so favorable as during the year 1905, at the works of the Algoma Steel Co., Sault Ste. Marie, Ontario, which comprise two modern blast-furnaces, well equipped, though of comparat.ively small capacity. For four consecutive months one of these furnaces was run with charcoal and the other with coke. Then the charcoal-furnace ran for a while with part charcoal and part coke; and, still later, with coke only. The ore-mixtures were

Jan 1, 1909

By John R. Hutchins

1ms is a report of nickel (wire) oxidation studies designed to test the validity of Valensi's1 equation developed for the kinetics of a reaction controlled by diffusion in a continuously growing product layer on cylindrical surfaces. The equation is:

Jan 1, 1968

In the death of Professor Hofman, the world has lost a great metallurgist and a great author of metallurgical literature. Measured in time, his life was not quite seventy-two years, but measured in work accomplished it was much longer than this. He was born Aug. 13, 1852 and died Apr. 28, 1924. It is not surprising that Doctor Hofman became a great scholar, for his father, Karl Hofman, was on the faculty of Heidelberg University, and his early days were spent in those surroundings. He studied in the university under such men as Kirchhoff and Bunsen and often spoke of his

Jan 1, 1924

Jan 1, 1959

By R. J. Lutton

Basic features occurring on tensile fracture surfaces in rock are hackle marks, steps, and rib marks. Rib marks define the leading edge of the fracture and indicate that it was free of irregularities. In turn, fractures characterized by these features are believed to have propagated elastically and to be truly brittle. On the other hand, most fractures in rock exhibit hackle marks and steps in a plumose arrangement, indicating a ductile fracture process. Accordingly, the edge of the fracture apparently advances by extending en echelon fingers, each of which is in turn a small plumose fracture. Plastic-like deformation takes place in this zone prior to complete rupture. Some of the propagation is directed sideways and some shearing also occurs in this direction. Such lateral movement contributes little to forward propagation and may make this process particularly sensitive to load rate and duration and help account for greater fracture strengths of materials under dynamic loads.

Jan 1, 1971