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By AIME AIME

ON the headwaters of the Hudson Riser, in a sparsely populated area of the north woods at Tahawus, N. Y., thirty miles from the nearest railroad, is the Maclntyre property of National Lead Co. Operations involve the mining and processing of titaniferous iron ore to produce ilmenite concentrate, and magnetite concentrate containing vanadium, for use in the production of iron, titanium, and vanadium in the war program. Accordingly, Maclntyre at present is classed as a war plant. More than 3000 long tons of ore is ruined daily by opencut methods and treated in an ore concentrating plant.

Jan 1, 1943

By Utley Wedge

(Cleveland :Meeting, October, 1012.) In general, the art of securing copper from sulphide ores or concentrates may be said to consist of : (1) separation, in the molten state, of copper sulphide with some iron sulphide, from the great bulk of gangue-material, followed by (2) elimination of sulphur and iron from the molten matte, by oxidation and fluxing, leaving metallic copper. The definition is made broad enough to cover the general practice, whether or not the ore or concentrate is given a preliminary roast for the removal of surplus sulphur. The above process, which I will designate as the smelting process, makes necessary the presence in the ore, or the addition thereto, of such silica, lime, and iron as may be necessary for the formation of a light and fusible slag, together with sufficient sulphur and iron for the formation of copper-matte, and also the addition to the matte of sufficient silica for the oxidation and fluxing-out of the iron. These items, together with the cost of fuel sufficient for melting the mass, constitute important items of cost in the copper-smelting process. Numerous cases where fluxing-materials are scarce or dear, or where fuel is expensive, have caused special attention to be given recently to the wet process of copper-extraction, which may be designated as consisting of forming soluble copper salts which are then washed or leached out of the ore or concentrates by dissolving in water or acid. Metallic copper may then be secured from the solution of copper salts by electrolysis; by cementation; or copper can be brought out of the solution as a * Presented also at the Joint Meeting of the Institute and Section IIIa, Metallurgy and Mining, of the Eighth International Congress or Applied Chemistry, New York, N. Y., September, 1912, and here published by mutual agreement.

Dec 1, 1912

By George B. Harrington

This paper is a brief description of the design and equipment of a new coal mine in southern Illinois, which has many features not common practice in shaft coal mining and which is laid out and equipped for such unusually large capacity that it promises soon to become one of the largest mining operations of its kind. Shaft sinking for the mine, New Orient, was commenced in May, 1921, by the Chicago, Wilmington & Franklin Coal Co. In October, 1924, the plant was practically completed and was producing over 6000 tons of coal per day. There is good prospect that within a few years, when the mine is fully developed and manned, the output will attain a daily rate of 12,000 tons. The coal seam at New Orient lies approximately horizontal, about 500 ft. below the surface, and may be said to run from 9 to 12 ft. in thickness. The tendency in Franklin County has been toward large mining units (5000 to 6000 tons per day) with great care being given to protection against fire and explosion hazards, and usually with quite elaborate surface plants permitting careful preparation of the coal into graded sizes comparable with those made in the anthracite region. The field is unionized, with uniform conditions of wages for various classes of work, hours, etc., and the Illinois mining laws are quite specific with regard to fireproofing and safety measures. These conditions make it difficult for any hut well-equipped and well-operated mines to meet the competition of the numerous fine properties of which this county can justly be proud. The coal company's property was already developed on the western side by the Orient mine—a much visited and written about operation (with which many of you are possibly familiar through the Department of Mines' film "The Story of Coal") which until recently held the 8-hr, production record with 8218 tons and usually ran quite consistently with production of slightly over 6000 tons per day. Experience at Orient wat naturally one of the greatest influences in determining the location and character of the New Orient.

Jan 1, 1925

By A. O. Drysdale

In Canada, the market for cement is not a national one but rather a collection of local or regional markets. Excess capacity on a national basis does not necessarily preclude a shortage on a regional basis. with portland cement selling for less than a cent a pound, the low price-to-weight factor makes transportation to the market a major cost item and thus a small plant can be justified to serve a limited regional market. The Brookfield plant of the Canada Cement Co. is designed to supply the Province of Nova Scotia, a regional market that shows promise of growing to a point where it will support a one-kiln plant. The market is presently being served by boat shipments from the Canada Cement Co. plant at Montreal East, Quebec, and from the North Star Cement Ltd. plant at Corner Brook, Newfoundland, and by rail and road shipments from the Canada Cement Co. plant at Havelock, N. B.

Jan 4, 1965

The Bureau of Mines extends. a cordial invitation to all members of the Institute to visit Pittsburgh, Sept. 29 to Oct. 1, to participate in the dedication of the Mines Experiment Station. Accompanying this will be a nation-wide participation in a First-aid and Mine Rescue Contest. The Pittsburgh Chamber of Commerce will cooperate. The Institute will be represented by a special delegate appointed by the President. MONDAY 8:30. A. M. Bureau Building open for inspection. 10:30 A. M. Dedicatory Ceremonies in rear of Main Building, .4800 Forbes St. 2:00 P. M.. Special Train and Automobiles to Experimental Mine near Bruceton, Pa. 3 to 6 P. M. Mine Explosion and Inspection of Experimental Mine . and of Explosives Testing Plant near Bruceton, Pa. 6:00. P. M. Return by Special Train and Automobiles to B. & 0. Station, Pittsburgh. 8:00 P. M. Informal Reception and Organ Recital Carnegie Music Hall. Arranged by Carnegie Institute of Technology.

Jan 9, 1919

By N. B. Wittman

The working of blast-furnaces is always of interest to many members of the Institute, for which reason I present an account of the working of the furnaces of the E. and G. Brooke Iron Company, of which I have had charge for the past four years. Although there are no phenomenal runs to record, there have been long periods of satisfactory work, and also periods—altogether too long—when one of our furnaces has behaved in a way which may be described as "nagging." All the conditions were apparently normal,but only a very light burden could be carried, which of course resulted in a high fuel-consumption to the ton of iron, as well as increased cost of labor. The two active furnaces of this company have the following dimensions and equipment : No 2. No 3. Feet. Feet. Height ....55 60 Diameter at bosh,.....- 15, 16 " hearth,...... 8 74 " stock-line,..10 91/2 Height of bosh,..23 23 " tuyeres,. 5 5 Diameter of bell,.7 6 Front,....closed open Both furnaces are blown with I. P. Morris condensing-engines, sim

Jan 1, 1890

By R. H. Martinson, E. Teghtsoonian

The effects of magnesium-rich surface layers of varying thickness on the mechanical properties of LiF have been studied. The yield stress, critical tensile stress, and work-hardening slope increase linearly with layer thickness, while the strain to fracture decreases yapidly with increasing layev thickness. The results of tension tests, supplemente!d by metallogvaphic evidence, indicate that the yield stress and the critical tensile stress of LiF are not determined by surface-source operation. DESPITE many studies, which have recently been reviewed,' certain fundamental aspects of the plasticity of LiF remain obscure. For instance, one question still awaiting a satisfactory resolution is: does the nucleation and/or multiplication of dislocations in LiF occur preferentially near the crystal surface? It is now well-known that mobile dislocation half-loops are readily introduced into LiF by surface damage and that the mechanical properties of LiF are affected by such surface damage. However, it is not known whether, in the absence of large numbers of artificially introduced surface sources, dislocations arise more easily near the crystal surface than in the crystal interior. It is also not known to what extent existing mobile dislocations multiply preferentially near the crystal surface. The present work is an experimental study of these matters. A short investigation of the effect of magnesium -alloyed surface layers on the deformation of LiF single crystals has been published by Westwood.~ Some relevant conclusions drawn from this research are restated here for purposes of comparison with the present work. 1) Tests on as-cleaved, chemically polished, coated and uncoated specimens show that a coating can restrict the operation of artificially introduced surface sources, thereby raising the yield stress. A coating also decreases the initial rate of work hardening of as-cleaved LiF crystals by reducing the number of active dislocation sources, so that mutual dislocation interference effects are lessened. 2) A catastrophic breakthrough of groups of edge dislocations piled up against the coating can cause stress drops in the stress-strain curve. 3) A surface coating can act as a stable barrier to the egress of dislocations, causing pile-up,

Jan 1, 1965

By L. C. Graton

At the Tenth International Geological Congress, Mexico, 1906, Waldemar Lindgren presented "The Relation of Ore Deposition to Physical Conditions." Retrospect ranks it as the outstanding offering at that Session and as the most fundamental contribution up to that date on the philosophy of ore deposition. Elaborating thereon in his text-book "Mineral Deposits," Lindgren analyzed ore-forming processes under conditions prevailing from great depth up to surface; explained the nature of deposition in each environment; and developed a comprehensive genetic ore classification, which brought wide acceptance and enriching contributions by many. Since Lindgren's latest edition (1933), have come wealths of material relevant to ore genesis, particularly through amazing renaissance and proliferation throughout science. Current publication regarding ores now emanates largely from a generation caught in pressures of the breathless modern tempo, which tempts scant reflection upon earlier truths. Consequently, today's thrilling output contains not a few offerings that need challenge because supplanting interrelationship and system by what seems, collectively, an assemblage of strange, ad hoc and often self-contradictory concepts. From these latter some merit may eventuate but at the probable cost of present confusion and delayed progress. The following pages, naming numerous post-Lindgren advances, record the conviction, held by many, that Lindgren's philosophy, progressively improved, remains the soundest approach to understanding ore genesis.

Jan 1, 1968

By R. M. Brick, Arthur Phillips, A. J. Smith

A PREVIOUS publication1§ has described the effect of quenching stresses on the lattice parameter values of high-purity aluminum-copper alloys particularly with reference to the solution and precipitation of CuA12. A similar study has been made of the aluminum-rich aluminum-magnesium alloys. Attention has been directed in the present investigation. to the magnitude of the quenching stresses as affected by the specimen size and shape, the number of solute atoms and the quenching rate. The effect of cooling stresses in causing plastic deformation or cracking has been considered in relation to the physical properties of the alloy. On reheating alloys in the two-phase field, the time required for precipitation to occur has been observed in connection with the degree of supersaturation, the rate of diffusion of the solute atoms as a function of the comparative atomic radii, degree of strain, temperature of reheating and grain size. A few qualitative comparisons on the relative effect of these factors have been drawn between the aluminum-copper alloys and the aluminum-magnesium alloys. STRAIN IN SOLID-SOLUTION ALLOYS A 10 per cent magnesium alloy in the form of chill-cast bars was furnished by the Aluminum Company of America through the courtesy of L. W. Kempf. Additional alloys were prepared using aluminum (99.95 per cent Al) and high-grade magnesium. The alloys listed in Table 1 were melted in an Acheson graphite crucible under a flux of fused MgCl2, CaC12, NaCl. Chill-cast rods were sealed under vacuum

Jan 1, 1935

By C. Goldberg, R. H. Wynne

WHEN using an optical goniometer to determine crystal orientation' it is advantageous to use a preferential etchant so that the etch pits have plane faces which are parallel to crystallographic planes, all of which are of the same "form." "Westinghouse Silver Etch" (WAg), a preferential etch for germanium, is made up as follows: 40 ml of 49.7 pct hydrofluoric acid, 20 ml of 70.7 pct nitric acid, and 40 ml of distilled water containing 2.0 g of silver nitrate. Examination of metallographs of WAg etched surfaces (Fig. 1, for example) indicates that, regardless of crystal orientation, the faces of the etch pits are (111) surfaces. Optical goniometer examination of these WAg etched surfaces also indicates that the faces of the etch pits are (111) surfaces, i.e., all bright reflections are from (111) planes. When using an optical goniometer of the type described by Barrett,' not only (111) reflections from a WAg etched germanium surface but also other reflections of lower intensity will be observed. These latter reflections can cause confusion. We have used an optical goniometer made from a war surplus astrocompass and a galvanometer lamp. The reflections are observed by using the goniometer in a darkened room and letting the reflected light be in- cident upon a piece of white paper. The resulting decrease of goniometer sensitivity enables (111) reflections only to be observed. This in turn permits the crystal orientation to be determined in a matter of minutes, since only two measurements are necessary. The authors wish to acknowledge the help received from R. E. Davis who assisted in making the metallographs and aided the authors in the interpretation of the metallographs.

Jan 1, 1954

By Henry Fay

The erosion of guns is a complex problem which can be solved only by a detailed study of all the factors involved. In the present paper it is proposed to submit the results of observations and experiments which have extended over several years. Certain facts have been established and preliminary reports have been published.' Conclusions have been reached since then which, it is believed, are worth presenting for the purpose of promoting discussion, and with the hope that ultimately the whole truth will be known. The particular phase of the problem which will be presented here is the hardening of the inner surface of the gun tube. It has been known for a long time that after firing a large caliber gun for some time, the surface of the metal becomes hard and brittle, cracks, and wears away.2 The character of this phenomenon may be learned by an examination of some results which are typical, obtained from a detailed study of a 12-in. gun. The gun was trepanned and rings representing various sections of the gun were cut out for examination. The first ring represented the metal at the muzzle end, and the other rings were removed at approximately 120, 240, 325 and 337 in., respectively, toward the breech end. The appearance of the surface of the metal in the different sections is shown in Fig. 1. The greatest amount of wear and maximum amount of hard surface layer was found in section marked E, which is nearest the powder chamber and at the beginning of the rifing; the maximum amount of cracking in D; the maximum amount of copper deposition in C. Section B showed heat cracks on both lands and grooves, and section A showed heat cracks on the driving edge of the lands only. There was much flow of metal in both sections E and D, and there was progressively less effect noticeable toward the muzzle end. The polished cross-section of these same pieces is shown in Fig. 2. The extent of the erosion is greatest nearest the powder chamber, and diminishes toward the muzzle end.

Jan 1, 1917

By W. B. Plank

RETURNS already received from a current survey of the enrolment of students in the mineral technology schools indicate a degree of activity and prosperity in those schools never before equalled. The returns are as yet too meager for accurate analysis, but those at hand point LO considerable increase in the metallurgical and petroleum engineering groups, and indicate that the total of 5011 two years ago in the United States schools will be substantially increased. Generally speaking, the enrolment is not only maximum in quantity but optimum in quality. Better income has sent the boys back to school, but the improved employment conditions have somewhat reduced the number of graduate students. Laboratories are commonly filled to capacity, in some instances overcrowded. Increased enrolment of foreign students from both Canada and South America is noticeable.

Jan 1, 1937

By W. A. Bruce

This paper covers the theory and present state of development of an apparatus for the nonmathematical analysis of complex problems of reservoir and well behavior. At the present stage of development of this apparatus, it is capable of solving the water-drive problem of any reservoir performance for which a mathematical solution has been presented in the literature, either on the basis of steady or unsteady-state flow analysis. The theory is presented for the extension of the scope of this analyzer along the lines of the present development. The resulting apparatus should be able to solve reservoir-performance problems previously thought too difficult for practical solution by mathematical means. As an illustration of its operation and present scope, the analysis of a reservoir problem and synthesis of expected performance is presented. Introduction In this method† of analyzing problems of petroleum-reservoir and well behavior, the porous continuum of the reservoir is assumed to be divided into small blocks, or units. Each block is assumed to be small enough so that for a material balance on the fluids in the block an average pressure for the block can be used. In analyzing reservoir behavior from this point of view by mathematical means, a set of simultaneous difference equations would be obtained (two for each block), which must be solved or combined into a partial differential equation. In the method to be described here, instead of solving these sets of equations analytically, electrical units are constructed, which will behave in respect to the flow of electricity exactly as the reservoir units behave under various conditions of fluid flow. The electrical units are then wired together in the same way that the reservoir units are connected naturally by virtue of their geometrical locations and shapes. Fluid-Flow Equations Consider a block in a reservoir. Assume that reservoir fluid (or fluids) is flowing in at one face and out at the opposite face, and that the block is small enough so that at all points the stream lines are within one degree of perpendicular to the face. Furthermore, assume that the pressure, pi, at the upstream face (Fig, I) is not more than one per cent greater than P2 the pressure at the downstream face. A material balance will show that the mass of fluid flowing out less the mass of fluid flowing in will equal the change in density times the fluid volume. This is expressed in the equation:

Jan 1, 1943

By W. A. Bruce

This paper covers the theory and present state of development of an apparatus for the nonmathematical analysis of complex problems of reservoir and well behavior. At the present stage of development of this apparatus, it is capable of solving the water-drive problem of any reservoir performance for which a mathematical solution has been presented in the literature, either on the basis of steady or unsteady-state flow analysis. The theory is presented for the extension of the scope of this analyzer along the lines of the present development. The resulting apparatus should be able to solve reservoir-performance problems previously thought too difficult for practical solution by mathematical means. As an illustration of its operation and present scope, the analysis of a reservoir problem and synthesis of expected performance is presented. Introduction In this method† of analyzing problems of petroleum-reservoir and well behavior, the porous continuum of the reservoir is assumed to be divided into small blocks, or units. Each block is assumed to be small enough so that for a material balance on the fluids in the block an average pressure for the block can be used. In analyzing reservoir behavior from this point of view by mathematical means, a set of simultaneous difference equations would be obtained (two for each block), which must be solved or combined into a partial differential equation. In the method to be described here, instead of solving these sets of equations analytically, electrical units are constructed, which will behave in respect to the flow of electricity exactly as the reservoir units behave under various conditions of fluid flow. The electrical units are then wired together in the same way that the reservoir units are connected naturally by virtue of their geometrical locations and shapes. Fluid-Flow Equations Consider a block in a reservoir. Assume that reservoir fluid (or fluids) is flowing in at one face and out at the opposite face, and that the block is small enough so that at all points the stream lines are within one degree of perpendicular to the face. Furthermore, assume that the pressure, pi, at the upstream face (Fig, I) is not more than one per cent greater than P2 the pressure at the downstream face. A material balance will show that the mass of fluid flowing out less the mass of fluid flowing in will equal the change in density times the fluid volume. This is expressed in the equation:

Jan 1, 1943

By E. P. Jennings

Large deposits of titaniferous iron-ore occur at Caribou, an old silver-mining camp in Boulder county, Colo., 17 miles west by south of Boulder, and a few miles northwest of the tungsten-mines. Professor Regis Chauvenet1 published a part analysis of the ore many years ago, but gave no description of the wall-rock. Caribou hill, which contains both the silver-bearing veins and the iron-ore deposits, is a low dome of gabbro surrounded by the Archæan schists and gneisses of the Front range of the Rocky mountains, the peaks of which, a few miles west of Caribou, attain an elevation exceeding 12,000 ft. The gabbro stock is roughly elliptical in outline, with approximate diameters of 1 and 3 miles. The crest of the dome is 10,500 ft. above sea-level, and the town and ore-cleposits are 500 ft. lower. Outcrops of the iron-ore occur in the town and extend NW. for 2,000 ft., where they disappear under the swampy meadows of Caribou park. Portions of the deposit are covered by drift, but one continuous outcrop is 900 ft. long and from 200 to 250 ft. wide. A second deposit is 0.25 mile south of the town along the eastern slope of the hill. It is not as well defined as the north bed, but is approximately 1,000 ft. long and from 100 to 200 ft. wide. The easily disintegrated ore does not form prominent outcrops, but the outlines of the deposits are readily traced by the large amount of ore fragments that cover the ground. Trenches and pits sunk on the outcrop expose a roughly banded magnetic iron-ore, with pyroxene as the principal gangue-mineral. The Gabbro. This rock was classified in the field as a gabbro from the presence of pyroxene and striated feldspars, and for convenience the field-name will be retained.

Jan 1, 1913

By R. E. Salvoti

IN underground coal mining, the increasing trend towards mechanical methods is ever apparent. Figures for 1939 showed that 28 per cent of the total bituminous coal production was mined mechanically 1940 statistic will reveal an even higher figure. Factors causing this trend are varied, but the important are the following;

Jan 1, 1941

By C. H. Mathewson

THIS paper was prepared upon request as a contribution to a symposium covering the manufacture, properties, and uses of the important non-ferrous metals. In approaching a subject as broad as this, there is a natural desire to build up a comprehensive and finished production which shall constitute a dependable source of information on all questions properly belonging to this branch of metal technology. There are, however, a number of circumstances, apart from the mere routine of labor and thought involved, which operate rather effectively against the possibility of completing such an ambitious program at the present time. First of all, as far as any public record of results is concerned, the commercial rolling, drawing, and forming of zinc with relation to changes of structure and properties-and this we consider to constitute the elements of metal technology-might as well be an unpractised art. We have never seen a published photomicrograph showing the structural characteristics of either hard or soft sheet or strip, although the structure of castings has been frequently described, and other coarse-grained structures resulting from hard-hammering and annealing have been reproduced. Thus, an author in this field must proceed to his task without much assistance from the literature, and the outcome can represent only a personal estimate of principles, facts, or findings, and not a summary

Jan 9, 1919

INDEX TO TRANSACTIONS After a delay of many months, which is very much regretted, but which, it is hoped, will be one means of insuring a volume of accuracy where accuracy is very important, the Institute now has for distribution copies of the index of Volumes XXXVI to LV, inclusive. This is more than a mere index off names of authors and titles of papers. Every important topic under consideration by author or discusser is introduced under such key-word as will enable an engineer to locate the desired information with the minimum expenditure of time. This index sells for $5* in half morocco binding and $4*. in paper covers. With the index of Volumes II to XXXV (which sells for $5 in half morocco and $4 in paper covers), it forms a complete index of the first fifty-five volumes of the Institute's Transactions. These collective indexes are very valuable to members of the Institute, enabling them to look up matters in their own library; if they have the volumes to which the indexes refer, they can get the information at once, and, if not, they can readily determine whether or not a visit to a nearby public library is desirable.

Jan 7, 1918

By J. D. Miller, A. Cortez, J. Hupka

The separation efficiency of the hot water digestion-flotation technique used for bitumen recovery from various domestic tar sands was evaluated. Bitumen viscosity was found to be the most important tar sand property in determining the success of the bitumen separation. Bitumen viscosity of the tar sand war controlled by changes in digestion temperature and/or changes in diluent (kerosene) addition. Complete and uniform dilution of the bitumen phase was achieved by providing a sufficient presoaking, or penetration time, for a given tar sand type. For all the tar sand samples tested, an excellent correlation was obtained between the coefficient of separation and the bitumen viscosity. To achieve a satisfactory coefficient of separation, it was found that the bitumen viscosity must be reduced below 1.5 Pa.s (16 P) at the temperature of digestion. This was the case regardless of the tar sand type, grade, or origin.

Jan 1, 1984

By V. T. BERNER

THIS apparatus was designed primarily to meet the demand for a quick, efficient stopping to seal off the burning area temporarily during a mine fire, but it can be used in any circumstance where an immediate brattice is required for ventilation control. In using the old style brattice, mine-rescue workers have found it difficult, in smoke-laden drifts and stopes, to erect an effective stopping with wooden frame and canvas. Stulls must first be cut to the proper length, the canvas tacked in place, and the numerous irregularities of the walls and back must be caulked. This operation requires the employment of axes, saws, and hammers, which cannot easily and safely be handled in dense smoke. The fire fighters have often been forced to abandon their brattice, unfinished, because of the rapid approach of the fire, or because of the exhausted sup- ply of oxygen in their breathing apparatus. It is neces-

Jan 1, 1930