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ALABAMA Anniston. Carrington, F. G. Ashland.-Herr, I. Auburn.-Brown, R. L. Bessemer.-Abbott, C. E. Dobbs, G. G. Ferguson, V. Salmon, H. S. Schaber, C. F. Birmingham.-Adams, J. H. Aldrich, T. H. Aldrich, T. H., Jr. Allen, A. W. Ball, E. M. Bonnyman, J. Bowron, J. Bush, M. W. Crawford, G. G. Crockard, F. H.

Jan 1, 1917

MANY kinds of marcasite* are found since every metallic mineral, and perhaps some of the semiminerals, produces its own. I believe that [28v] rnarcasites are nothing other than the secondary materials and the menses of the conception of metals which, through insufficient time, have yet to arrive at their perfect age; and thus, because of

Jan 1, 1942

By R. Y. Williams

In the United States, fully 98 per cent. of the anthracite and bituminous coal tonnage obtained from underground operations is mined by the room-and-pillar system. Under this system, the total cost of the coal f. o. b. railroad cars contains as its greatest single item the money paid for "labor." Each labor dollar in an average bituminous mine may be subdivided into 85 c. paid for work done inby the gathering turnouts (including all work at the face), and 15 c. outby that point (including all work in and under the tipple). In an average anthracite mine, the corresponding figures are 70 c. and 30 c., the larger breaker force accounting mainly for the difference between these and the bituminous figures. The next largest single item after "labor" is usually "supplies and power;" and a division of this item inby and outby the gathering turnouts shows somewhat the same relative proportions as has been noted under the case of "labor". During the past 10 years, the chief advances made in the coal industry have been to obtain economies through complete mechanization covering that portion of the work which lies outby the gathering turnouts. These results have been accomplished by applying scientific principles to railroad yard layout, to cleaning and sizing machinery, to dumping facilities, to roller-bearing haulage equipment, and to heavy-rail, well-ballasted trackage. But these improvements, while gratifying in their resulting economies, apply only to 15 to 30 per cent. of the important cost items. Obviously, then, the big problem before the engineers of the coal industry today has to do with the methods of mining and the layout inby the gathering turnouts. Four years ago, Weston Dodson & Co., Inc., determined to have an exhaustive study made of the conditions which must be met in order to gain complete face mechanization, and in order that such a mining layout would be based on correct underlying principles. The result of that study, which was made by the writer, led to the adoption of a method of longwall mining wherein the roof is worked on the caving system and is supported as an overhang along the face by steel jacks.

Jan 1, 1928

By L. S. Darken

IT has been known for sometime that in an ionic lattice, such as that of Ag2S or FeO, the migration velocity of the anion may differ markedly from that of the cation, the cation being usually the more mobile. It has been shown, for example, that during the formation of silver sulfide tarnish on silver, the tarnish layer grows principally by the motion of silver cations through an essentially stationary silver sulfide lattice. Similarly, the growth of wüstite scale on iron proceeds principally by motion of iron ions, this being accomplished with the aid of vacant iron lattice sites into which the iron may readily move. Likewise investigations of solid solutions of various salts show that there is usually considerable difference in the mobility of the different cations. Measurements of the mobility of various metals in liquid mercury indicate that the various metals move at different rates relative to the mercury. In view of the foregoing it seems reasonable to suppose that when any single phase solution is acted upon by a field, the atoms of different elements respond in different ways; in particular, that the force arising from a particular concentration gradient in a binary alloy would cause the atoms of one component to move with a drift velocity which is in general different from that of the atoms of the other component. The recent experiments of Smigelskas and Kirkendall1 support this viewpoint, since they found, in essence, that during diffusion in alpha brass zinc moves appreciably faster than copper. This was evidenced by the relative motion of inert molybdenum wires. Such a phenomenon is incompatible with the place interchange theory of diffusion proposed by several authors, most recently by Birchenall and Mehl.2 This theory has, however, also been questioned3.4 for other reasons, principally because of the high energy required for direct atomic interchange. The rather large difference between self-diffusivity, as determined by tracer technique, and mutual diffusivity, as determined with the aid of another element at low concentration, might also be interpreted as favoring the above idea; however, Birchenall and Mehl have pointed out that there is another possible interpretation of this difference; this is discussed later. A rather interesting and pertinent observation was made by Schwartz,5 who noticed that tungsten lamp filaments, heated by direct current, commonly fail by necking down in the region at the temperature gradient near the positive end, with a concomitant swelling at the corresponding position near the negative end. He introduces considerable auxiliary evidence to show that this phenomenon is occasioned by the motion of tungsten cations which migrate in the high temperature region from the positive end toward the negative end. The mechanism of this migration is not clearly understood. If, however, this experimental evidence be accepted, we are forced to conclude that alloying elements in the tungsten may migrate by the same or a similar mechanism, whatever it may be, at a greater or lesser rate, thus giving rise

Jan 1, 1948

Executive ROBERT E. TALLY, Chairman WILLIAM H BASSETT JOHN A. MATHEWS Louis S. CATER EDGAR RICHARD Finance HENRY KRUMB, Chairman H A GUESS H G. MOULTON Admissions ERLE V. DAVELER, Chairman GEORGE D BARRON H K MASTERS JOHN M. LOVEJOY P. A.-MOSMAN Alternates E. L. ESTABROOK C. E MEISSNER J. A. SINGMASTER FRED H. KAY

Jan 1, 1923

Executive ROBERT E. TALLY, Chairman WILLIAM H. BASSETT JOHN A. MATHEWS LOUIS S. CATES EDGAR RICKARD Finance H. A. GUESS HENRY KRUMB, Chairman H. G. MOULTON Admissions ERLE V. DAVELER, Chairman GEORGE D. BARRON H. K. MASTERS JOHN M. LOVEJOY P. A. MOSMAN Alternates E. L. ESTABROOK C. E. MEISSNER J. A. SINGMASTER FRED H. KAY

Jan 1, 1929

By Millard K. Shaler, Sydney H. Ball

During the past 50 years the attention of mining-men has been turned to Africa, and within the past decade prospecting-expeditions sent into Central Africa have resulted in the open-ing-up of several mines. Having recently spent two years in the Belgian Congo for the Societe Internationale Forestiere et Miniere du Congo, it is our purpose to outline briefly the mining-conditions in that part of Central Africa. Before it became, in 1908, a Belgian colony, this region was known as the Congo Free State. 11. Location and Area. The Belgian Congo lies in southwestern Central Africa, west of the continental divide, as illustrated in Fig. 1. It has a coastline of but 20 miles on the Atlantic, but widens rapidly eastward to points 5 north and 14 south of the equator. Its area is 908,000 sq. miles, which is almost one-quarter that of the United States and Alaska, or more than one and one-half times that of Alaska. Stated in other terms, its area is nearly one-third that of the United States, exclusive of Alaska and the insular possessions, or more than that of all the United States east of the Mississippi river. III. Topography and Drainage. From north to south, Africa is made up of three topographic elements: 1, the Atlas mountains, a highly-accentuated region

Jan 1, 1911

By George K. Burgess, Robert A. Hadfield

1. Introduction.—The methods of production of sound steel ingots have been described in several papers read recently before this Institute. It was thought by Director Stratton, of the U. S. Bureau of Standards, and ourselves to be of sufficient interest and importance, as a further contribution to this subject, to compare the properties of rails rolled in one mill according to American practice, from several types of ingot of substantially the same chemical composition but cast by several processes; and to compare in considerable detail the properties of an ingot manufactured by the Hadfield special-feeding process and one of the usual type for rolling into rails. We are greatly indebted to F. W. Wood, President of the Maryland Steel CO., who made this investigation possible by kindly placing his rail mill at our disposal; and he and his associates at Sparrows Point did everything possible to make the experiment a success, including the execution of several of the tests and analyses. 2. Classification and Manufacture of Ingots.—Of the ingots used in this investigation, eight were made in Sheffield and furnished by Sir Robert Hadfield, and one was made and furnished by an American steel company,l as a comparison ingot, and was supposed to represent the usual type of ingot from which rails are made. The characteristics of the ingots are given in Table I. Ingots 1, 2, 3, and 4 were cast large end up and fed by the Hadfield method in the usual manner with charcoal and blast continued until the molten steel has set on the top of the head, say varying from 20 to 40 min. To ingots 1, 2, and 4 was added 0.1 per cent. aluminum, and to the nickel-chrome ingot, No. 3, 0.125 per cent. For sake of comparison, there were also included two ingots, Nos. 8 and 9, cast with the small end up and fed by

Jan 1, 1915

By Kenneth Seaver

It is rather gratifying that in the field of the manufacture of refractories, in which, as a whole, foreign practice has surpassed us, the United States stands pre-eminent in the making of silica brick. In some instances European manufacturers have refused point-blank to credit the possibility of making to such specifications as are Common with us, until the actual completed shapes were shipped for inspection. But both the manufacturer and consumer in foreign lands are now frankly learning from us, and benefiting by our advanced practice in this field, as is evidenced by the orders placed here and the efforts put forth abroad to come up to the standard of American-made material. In no metallurgical operation has the employment of silica brick spread with such leaps and bounds as in the building of plants for the carbonization of coal, particularly in the byproduct coke oven. Today, in practically all types of oven, the structure above the floor level (except the facings) is of silica, while in the recuperative and in some regenerative types, its use is extended to that portion of the oven below the floor as well. By reason of the fact that there are a number of classes of refractories of higher silica content than the usual so-called fire-clay brick, there is sometimes a misunderstanding as to the class of material referred to as "silica" brick. We here refer only to a brick having a silica content of 94 per cent. or more and made usually from quartzite rock with a small percentage of lime as a binder. The term "silica" brick is sometimes rather loosely applied to brick from highly siliceous clays, or to a quartzite refractory of mingled fire-clay and quartz rock; but such products are not considered in this discussion. : Materials The rock from which practically all high-grade silica brick are made is a true quartzite or metamorphosed sandstone, variously known as

Jan 1, 1916

By AIME AIME

ON MAY 22 the American Institute of Mining and Metallurgical Engineers will commemorate the sixtieth anniversary of its founding at Wilkes- Barre, Pa., in May, 1871. The Directors have transferred the May meeting of the Board to Wilkes-Barre, and the Pennsylvania Anthracite Section has invited as many members of the Institute as can to be present at this time and to join with their fellow-engineers at Wilkes-Barre in the inspection trip through a portion of the anthracite district that has been planned. Ac- cess to Wilkes-Barre is easy, from nearby points, over excellent automobile roads, or by train. The distance from New York is only about 140 miles. , It is hoped to engage a special car for those travelling by train from New York, which will leave the Pennsylvania Station over the Lehigh Valley Railroad at 11:50 p.m., arriving in Wilkes-Barre the next morning. Return can be made from Wilkes-Barre by sleeper the same evening, arriving in New York Saturday morning. Other trains are available for those who prefer a daylight journey.

Jan 1, 1931

By F. L. Wolf

THE catenary system of line construction possesses so many desirable characteristics from the operating standpoint that it has wide application for all types of electric traction. Many steam roads are electrifying sections of their lines, and in most cases are operating both steam and electric locomotives over the same track. This' means that the overhead catenary system is subjected to the severe corrosive action of locomotive smoke, and data concerning the resistance of various alloys to this form of corrosion are very desirable from every point of view. Reliable and specific information and data on the subject of corrosion due to steam and smoke from locomotives are extremely meager and, on this account, extensive service tests, together with accelerated tests, have been made on a number of commercial metals and alloys. The observations and data recorded in this paper are the result of a, preliminary test which was started in 1923 and which has been carried on to the present time. The recognition of the need for even more detailed and accurate data has resulted in the undertaking of another test which has been in progress for about a year. The result of this test will be published in due course. Some years ago The Ohio Brass Co. was asked by one of the large steam railroad companies to furnish data on construction details for a catenary system which it was considering for one of its divisions. The selection of, materials which would give the necessary physical characteristics as well as withstand the severe corrosive action of locomotive gases caused electrical railroad engineers considerable concern. At that time, there were available no specific or authentic data on these important questions: no systematic investigation of the problem appeared to have been made, even though its importance was generally recognized. Such observations as had been made were crude in that they had been limited largely to visual inspection which too frequently is most misleading. However, the scattered information which was collected gave important clues as to how best to start an investigation.

Jan 1, 1930

By E. S. Greiner

STUDY of the plasticity of germanium or other semiconductor crystals affords unusual opportunities to extend our knowledge of deformation mechanisms. Crystals are available having extraordinary perfection and very high purity. They deform by slip on the systems {111} <110>,1-3 as do crystals of the simple face-centered-cubic structure. Dislocations generated in them during slip are easily revealed in the form of etch pits on either (111) or (100) surfaces.4,5 This fact alone makes possible more detailed studies of mechanisms than is usually the case with metals but, even further, the effect of deformation on their electrical conductivity is very large compared with metals. This comes about not only because the mobility of the charge carriers is reduced, as in deformed metals, but also because the number of these carriers is greatly altered. This latter effect seems closely related to the formation of both line and point imperfections during deformation and thus provides a needed tool for the study of the kinds and distributions of these imperfections. Other investigators have deformed germanium at elevated temperatures by bending,1, 6-8 compres-sion,6, 0,10 tension,2,3,6,11,12 torsion,23 and indentation." Wang and Alexander" have also reported successful indentation at room temperature. Dislocation etch pits consequent to deformation have been observed and studied.7,8,10,18,14,20 The experiments to be de- scribed here include principally the compression and the subsequent annealing of germanium with concomitant studies of etch pits, microstructures, and electrical properties. Both single crystals and heavily twinned specimens were used. Some indentation studies are included. Experimental Methods Plastic compression was effected in the apparatus shown schematically in Fig. 1. It consists of two tantalum platens contained in a helium atmosphere and so arranged that pressure can be applied by a hydraulic press. The specimen between the platens is heated by the surrounding furnace. The specimen is usually a small crystal cube about 0.30 in. on an edge. A control specimen is always inserted so, that it is subject to the same thermal cycle as the one being deformed. This serves to detect any impurity contamination that might accompany the thermal treatment. For high temperature work, where such impurity contamination often occurs, the specimens were first plated with gold whenever subsequent electrical properties were to be determined. This method" is effective in preventing significant contamination of germanium up to temperatures at least as high as 750°C, as evidenced by the constancy of the electrical conductivities of control specimens subjected to the same heat treatments. The total range of temperature used for deformation was from 375°C, the lowest at which significant flow was observed, up to 900°C. Microscopic examination was made after mechanical and chemical polishing and etching. Dislocation pits were revealed with CP-4 etchant by the tech-

Jan 1, 1958

By V. H. Gottschalk

THE solubility of gases in metals has been of interest since Graham&apos;s time in 1866, but, although the subject was actively studied by iron and steel metallurgists during the eighties, the era of painstaking laboratory investigation begins in 1907 with the publication of Sieverts&apos;1 thesis on the occlusion and diffusion of gases in metals. Since then, Sieverts has worked almost continuously in this field, and his views on the subject are the prevailing ones at the present time.2 Probably the most important result obtained by Sieverts, and frequently verified since by other observers, is the discovery that at a constant temperature the solubility of almost all gases in both the liquid and solid state of most of the metals is proportional to the square root of the pressure (for pressure above 100 mm.). The obvious explanation of this fact is that the gas dissolves as atoms and not as molecules, although it has been pointed out a number of times, first by Donnan and Shawl in connection with their work on the solubility of oxygen in silver at 1075° C., that the formation and solution of a compound of the metal and gas would also be indicated by a variation of the solubility with the square or higher root of the pressure. Sieverts4 himself raised the question whether the usual explanation (i. e., that the gas dissolves as atoms) may not be wrong, when he found that the square root law held also for the solubility of sulfur dioxide in molten copper; in which case dissociation into simpler molecules or atoms does not take place. Stubbs5 subsequently showed that Sieverts and Krumbhaar&apos;s "constant" for sulfur

Jan 1, 1932

By AIME AIME

THE second session on geophysical prospecting at the February meeting of the Institute was a discussion of the mining law and the bearing of the new method of search on location of claims and assessment work thereon. Allen H. Rogers was chairman of the meeting, which he opened by reviewing the present law and the proposed changes. W. R. Ingalls commented (by letter) on the Arentz bill, as introduced into the House of Representatives in 1921 and the need for revision of the present mining law. L. W. Douglas explained (by letter) the bill that he introduced and which has been passed by the House. SAMUEL S. ARENTZ, Nevada: It is my opinion that if the American Institute of Mining and Metallurgical Engineers is to sell this proposition to the people in the West, they have to sell it to the lawyers, because, after all, they are heard loudly when it comes to speaking in Congress. One man tells the other, "This thing is a vicious piece of legislation"; it might not be, but they will pass it on if it affects them. If the Institute would impress on the people affected that we need a re-codification of the mining law and that such is necessary along certain lines; that things have changed during the past decade or two, so today instead of doing our prospecting alone through the sinking of a shaft, through a discovery that may be seen, we are now moving on to more modern means of discovery through geophysics, through the churn-drill, through geology, through geological inference, I think we could get somewhere.

Jan 1, 1929

By G. W. Josephson

VIRTUALLY every year inventors find one or more startling new uses for one of the varied products of the nonmetallic mineral industries. For example, in November a major step toward positive control of rainfall was made when an experimenter converted a cloud to snow by dropping a few pounds of solid carbon dioxide into it. Other examples of ingenuity in the development of markets and production methods are noted in the following pages. For most of the industrial mineral products one of the outstanding features of 1946 has been the high level of production. There are exceptions, such as quartz crystal and lithium, whose production capacity during the war outgrew current peacetime needs, but they are few. Some technical men point out that this prosperity is not an unmixed blessing to technologic progress, because so much effort must go into day-to-day production problems that relatively little opportunity is left for the pursuit of new developments.

Jan 1, 1947

By Shiro Ban-ya, John F. Elliott, John Chipman

The activity of carbon in Fe-C austenite at 1150°C has been determined for concentrations up to about 2.1 pct C using the equilibrium: C + COz = 2CO; equations have been derived expessing the activity as a function of carbon content on the basis of twelve mathematical models. Several of these represent the data satisfactorily. ACCURATE information on the thermodynamic properties of austenite in the binary system Fe-C is needed as a basis for studies of transformation and precipitation in steels of all sorts, alloy as well as plain carbon. The many attempts to approach this problem through statistical thermodynamics require sound and dependable experimental data in order to evaluate the several models which have been suggested. In this paper we are concerned with the experimental determination of the activity-composition relation in austenite at the temperature of its widest range of stability, approximately the eutectic temperature (1153°C). Accurate investigation of the activity of carbon in austenite may be said to have begun with the work of Dunwald and wagner.&apos; A more detailed study was carried out by R. P. smith2 on the two equilibria: More recent work on these two equilibria has been reviewed by Chipman,3 who pointed out the experimental hazards associated with studies of Eq. [I]. Studies of this reaction involve rather small values of the ratio these are susceptible to errors due to traces of moisture in the apparatus according to the reaction: Ellis, Davidson, and Bodsworth4 evaluated K, for their experimental temperatures and used desiccants to control water vapor pressure. While they were able in this way to obtain consistent values for K1 it cannot be said that all of the uncertainties of the method have been overcome. Results by both methods reported by Schurmann, Schmidt, and wagener5 appear to be consistent except at very low carbon content. Reaction [2] was employed in the experimental work reported here. It is to be recognized, however, that it is not applicable to projected studies of certain alloy steel compositions involving stable oxide-formers.

Jan 1, 1970

J. E. Stead, Middlesborough, England (communication to the author): Prof. Howe&apos;s valuable paper on cast-iron brings forward most prominently the correct explanation of the part played by combined carbon in pearlite and cementite, in determining the strength and hardness of cast-iron. On a previous occasioil I have shown that castings made by melting a white Cleveland iron and glazed iron, one containing 1.5 and the other from 4 to 5 per cent. of silicon, and each about 3 per cent. of carbon, were stronger than those made of ordinary foundry-iron; the difference in the final castings being a differ-

Jan 1, 1902

It is not often that a mining district is discovered, opened up, exploited and developed into a rich producer within the space of three or four years. Not until the year 1903 was the existence of the rich cobalt-nickel arsenides and silver of Northern Ontario even suspected by the mining public. But it is worthy of record that Dr. W. G. Miller, the man who has done so much to develop sanely and honestly the mineral resources of Ontario, pointed out [ ] the possibilities of this region at least two years before the first discovery was made. . Dr. Miller, then Professor of Geology at the School of Mining, Kingston, Ont., referred in these words to the district: "It will be seen from what has been stated on preceding pages that the district examined contains as great a variety of rocks as probably any part of the Province of equal area . . . Although few discoveries of economic minerals have been made in this territory, it may reasonably be expected that deposits of value will be found when

Jan 1, 1907

By J. H. Henderson, H. J. Ledbetter, N. B. Gove, J. D. Griffith

INTRODUCTION The results of a series of laboratory flood tests using liquid Iso-butane to displace refined oils from test cores are pre- ented and interpreted on an empirical bask. The study Revealed the similarity of the miscible liquid displacement to that of the immiscible-fluid displacement mechanism. The efficiency of the iso-butane flood decreased markedly as the oil Viscosity increased. but the effect of injection rate on the effectiveness of the primary production stage was negligible over the range investigated. The presence of free-gas saturation prior. to iso-butane breakthrough increased the volume of iso- Butane required to recover a given percentage of the oil present. Injection of liquid i.e.-butane prior to water follicle sculpted in a marked improvement in oil recovery by the water flood. INTRODUCTION The production of petroleum is often enhanced by the injec-1i1)n of extraneous fluids into the reservoir. It has been suggeited that the injection or cycling of a wet gas or a liquefied petroleum gas would he instrumental in increasing the effic.ienr!; of oil recover! to a greater degree than the commonly injected fluids. dry pas and water. Although instances of injection of light liquid hydrocarbons are not unknown, a systrmatic recording of the result is unavailable and superfi- cially, the practice gives the impression of being economicaIIy unsound. For specific types of displacement, analytic: solutions have been advanced which aid in understanding the physical mechanisms involved. However, there is no generalized theoretical concept which permits adequate prediction of displacement efficiency from a knowledge of readily measured reservoir rock and fluid properties. The Buckley-Leverett approach to oil displacement by an immiscible phase is an admirable analysiy of that type of mechanism. Dykstra and Parsons have introduced a useful concept in their evaluation of the role of the mobility ratio and its merit in rationalizing displacement phenomena. Everett, Gooch and Calhoun3 in their report on the effect of viscosity ratio and miscibility have pointed out the lack of a comprehensive theoretical approach and the desirability of investigating the mechanism of miscible-miscible displacement. In lieu of a well-developed theory concerning miscible-111isci1)le displacement and in view of the scarcity of engineering information on actual LPG injection trials, the limited program of laboratory experimentation described below was undertaken. OBJECTIVES The original broad objectives of the program, to study the oil recovery process using LPG as the displacing phase, defined the direction and scope of the laboratory tests. The specific objective. of the experimentation were to evaluate

Jan 1, 1953

By Charles Austin

IN an earlier series of studies on 18-8 stainless steel at 600°, 700°, and 800°C.1 one pretreatment was used throughout; viz., 15 min. in hydrogen at 950°C., followed by an air quench. Several manufacturers of this alloy since have expressed doubt as to the suitability of the temperature employed, recommending instead the more customary Strauss treatment as promising superior results. In this subsequent investigation on the effects of the temperature of pretreatment several interesting points have arisen, which are described in this paper. Previous work on our equipment had shown a marked difference between alloys of "similar chemical composition" that had been manu-factured by different companies. Accordingly, one mill-bar length was selected from which to prepare all specimens. It could then be assumed that any marked differences in creep characteristics would be due to effects resulting from variations in the pretreatment of the alloy. The material was furnished by the Allegheny-Ludlum Steel Co. in the form of 5/16-in, dia. rod, finished by air cooling from a mill anneal at 1950°F. (1066°C.). It was analyzed only for the elements shown: carbon, 0,07 per cent; chromium, 18.73; nickel, 9.46; manganese, 0.40. Three pretreating temperatures were chosen, the specimens being held for 15 min. in hydrogen at either: (1) 1150°C., to conform to the recom-mended Strauss treatment; (2) 950°C., to compare with the results of previous tests; or (3) 750°C., to initiate precipitation of carbides in the material before testing. As the test cross sections were only 1/8 -in. dia., air cooling followed the annealing treatment. These treatments per-mitted two direct comparisons: (1) between the 1150° and 950°C. treat-ments to indicate the effect of grain size when all carbides were probably in solution at the start of the test; and (2) between the 950° and 750°C. treatments to indicate the effect of carbide "nucleation" for similar grain sizes.

Jan 1, 1940