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By Frederick M. Becket

DoctoR Albert Sauveur, distinguished scientist and Honorary Member of this Institute, predicted in the first Howe Memorial Lecture that the privilege of delivering' this annual address would be considered a highly significant honor. The intervening years have well borne out Sauveur's prophecy. I wish to assure the American Institute of Mining and Metallurgical Engineers that I also deeply appreciate this honor, recognizing at the same time the present and even more the future responsibilities with which it is accompanicd. Several of the previous lecturers had the good fortune to attend the classes of Professor Howc and to work in his laboratories. I was similarly favored, although in my instance and to my great regret the period was all too short. However, Howe's book, published in 1903, "Iron, Steel and Other Alloys," afforded me abundant opportunity to continue these studies. How well I remember the inspiration I derived from this famous book by Howe, the metallurgical master, pioneer, and educator! Remembering that Professor Howe contributed numerous papers to The Metallographist, a magazine supported from a technical point of view by the world's pioneers in metallography, I was curious a few days ago to learn the nature of Howe's early contributions to this magazine. The first paper by Howe in the first year of The Metallographist (1898) dealt with the allotropic theory; the second also treated of allotropy, and I quote the first sentence of that paper: The allotropic theory of the hardening of steel may, like so many other important theories, have to be accepted or rejected not on direct proof or disproof, but on the accumulation of circumstantial evidence for or against it. Howe's ability to stimulate others by his deep understanding and clarity of expression was truly remarkable; but just as striking was his intuitive judgment concerning the implications of metallurgical data in the arts and scienees. It therefore seems fitting that this lecture comprise a broad treatment of the subject chosen, rather than a closely documented thesis on any one phase of the problem; that in it attention be focused

Jan 1, 1938

By Frederick M. Becket

DoctoR Albert Sauveur, distinguished scientist and Honorary Member of this Institute, predicted in the first Howe Memorial Lecture that the privilege of delivering' this annual address would be considered a highly significant honor. The intervening years have well borne out Sauveur's prophecy. I wish to assure the American Institute of Mining and Metallurgical Engineers that I also deeply appreciate this honor, recognizing at the same time the present and even more the future responsibilities with which it is accompanicd. Several of the previous lecturers had the good fortune to attend the classes of Professor Howc and to work in his laboratories. I was similarly favored, although in my instance and to my great regret the period was all too short. However, Howe's book, published in 1903, "Iron, Steel and Other Alloys," afforded me abundant opportunity to continue these studies. How well I remember the inspiration I derived from this famous book by Howe, the metallurgical master, pioneer, and educator! Remembering that Professor Howe contributed numerous papers to The Metallographist, a magazine supported from a technical point of view by the world's pioneers in metallography, I was curious a few days ago to learn the nature of Howe's early contributions to this magazine. The first paper by Howe in the first year of The Metallographist (1898) dealt with the allotropic theory; the second also treated of allotropy, and I quote the first sentence of that paper: The allotropic theory of the hardening of steel may, like so many other important theories, have to be accepted or rejected not on direct proof or disproof, but on the accumulation of circumstantial evidence for or against it. Howe's ability to stimulate others by his deep understanding and clarity of expression was truly remarkable; but just as striking was his intuitive judgment concerning the implications of metallurgical data in the arts and scienees. It therefore seems fitting that this lecture comprise a broad treatment of the subject chosen, rather than a closely documented thesis on any one phase of the problem; that in it attention be focused

Jan 1, 1938

By Frederick Mark Becket

DOCTOR Albert Sauveur, distinguished scientist and Honorary Member of this Institute, predicted in the first Howe Memorial Lecture that the privilege of delivering this annual address would be considered a highly significant honor. The intervening years have well borne out Sauveur's prophecy. I wish to assure the American Institute of Mining and Metallurgical Engineers that I also deeply appreciate this honor, recognizing at the same time the present and even more the future responsibilities with which it is accompanied. Several of the previous lecturers had the good fortune to attend the classes of Professor Howe and to work in his laboratories. I was similarly favored, although in my instance and to my great regret the period was all too short. However, Howe's book, published in 1903, "Iron, Steel and Other Alloys," afforded me abundant opportunity to continue these studies. How well I remember the inspiration I derived from this famous book by Howe, the metallurgical master, pioneer, and educator! Remembering that Professor Howe contributed numerous papers to The Metallographist, a magazine supported from a technical point of view by the world's pioneers in metallography, I was curious a few days ago to learn the nature of Howe's early contributions to this magazine. The first paper by Howe in the first year of The Metallographist (1898) dealt with the allotropic theory; the second also treated of allotropy, and I quote the first sentence of that paper: The allotropic theory of the hardening of steel may, like so many other important theories, have to be accepted or rejected not on direct proof or disproof, but on the accumulation of circumstantial evidence for or against it. Howe's ability to stimulate others by his deep understanding and clarity of expression was truly remarkable; but just as striking was his intuitive judgment concerning the implications of metallurgical data in the arts and sciences. It therefore seems fitting that this lecture comprise a broad treatment of the subject chosen, rather than a closely documented thesis on any one phase of the problem; that in it attention be focused

Jan 1, 1938

By Paul B. Barton

Unconventional mineral deposits are those that differ significantly from productive deposits in mineralogy, grade, or geologic setting. Thus, the initial representatives of each deposit type are, by definition, “unconventional” until they are exploited. The “unconventional” status changes to "conventional" because of economic shifts (e.g., bulk silver ores), because of technological innovations (e.g., froth flotation), or simply through the recognition of, and production from, novel mineral concentrations. Heretofore the discovery of new deposit types has been almost entirely accidental, but the long- established concept of the geochemical cycle provides a nearly untouched opportunity and challenge for the application of geochemistry in predicting novel, potentially economic, mineral concentrations.

Jan 1, 1983

By David W. Brunton

The list of our past-Presidents comprises the names of many who, in their official addresses, have sketched the current progress of the arts and professions with which they were familiar. Such addresses are, in my judgment, highly useful, setting forth the results of our own work as a society, and recalling to our minds the particular lines in which discussion would prove most fruitful. Following this course with some hesitation, I venture to offer an outline of the recent improvements and the present situation in mining and metallurgy in the Western United States. The wonderful advances in mechanics, chemistry, and electricity have all combined to aid these arts to such an extent that progress during the last decade has undeniably been more rapid than ever before in the history of the profession. In all mining countries improved transportation-facilities, in many instances called into existence by the traffic created by the mines themselves, have done much to enlarge the field of operations by the reduction of freight-, operating- and living-expenses, thereby bringing lower-grade properties into the producing class. Under normal conditions, as the age of a district increases, all these different factors should combine to off-set the augmented costs attendant on deep mining, and greatly tend to prolong the profitable life of the mines. The more recent and important improvements in our Western mining-practice which have contributed most towards the advancement of the art may be briefly summarized as follows; but, before beginning this portion of my address, I wish to thank most heartily the many engineering friends who have so

Jan 1, 1910

By Gernot Kostorz

In a recent paper, Raffo and itcheell1 compared solid solution hardening of various bcc alloy single crystals at room temperature and concluded that the expression for localized elastic interaction between dislocations and solute atoms2 that gives the critical resolved shear stress (CRSS) 7,: to = Z . µE3/2 C1/2 where c = concentration, e = misfit parameter, (µ = shear modulus, Z = numerical constant Fig. 1—The slope dT0/dc1/2 for niobium alloy single crystals deformed at 570°K plotted against the misfit parameter € = In' I + 1616 I. from Ref. 6, •estimated from Ref. 7. Table I. Plateau Hardening and Alloy Parameters for Niobium Alloys dT0/dc1/2, kg/mm2 Solute Ref. 6 Tantalum 3.7 ± 0.3 1.9 0.73 + 0.06 9 0.0 ± 0.5 15 Vanadium 16.1 ±1.4 - 0.69 i 0.01 9 -7.4 ± 0.5 16 Tungsten 12.5 ? 1.5 20.9 0.92 i 0.05 10 -5.0 t 0.4 17 Rhenium - 25.9 1.24 11.12 -8.5 ± 0.4 I5 Molybdenum - 14.6 1.04 13,14 -4.6 s†±?˜µ?fF?? 0.5 17 Hafnium - 13.9 0.37 12 4.8 ± 0.5 17 Table 11. Solid Solution Hardening and Alloy Parameters for Tantalum Alloys i)' dTo/dc1/2 kg/mm2, dTp/dc1/2 kg/mm2, Ref. 22 1006 Solute ˜570°K Ref. 7 See Text Ref. 25 Rhenium 44.3 32.5 0.65 -8.5 Tungsten 32.1 24.3 0.34 -4.6 Molybdenum 29.3 19.1 -0.19 -5.9 Niobium 5.8 5.5 -0.43 0.I

Jan 1, 1970

By F. G. Jaicks

RECOGNITION of the benefits to be gained from the continuous casting of molten steel into finished or semifinished products has been given by scientific minds since the very beginnings of steel plant technology. In fact, Sir Henry Bessemer is credited with the first of a long list of patents' issued by the U. S. Patent Office for a process which would accomplish this desirable end. None of these early ideas attained practical success and, as a result, the conventional method of teeming into ingot molds became an integral part of modern steelmaking operations. This procedure, although refined to keep pace with the changes which have come about in steelmaking and finishing facilities, is recognized to have inherent shortcomings which adversely affect manufacturing costs and steel quality. Interest in the continuous casting of steel persists because the process is directed toward avoiding some obvious weaknesses of conventional ingot casting. It has been recognized that should it be possible to substitute any of the continuous casting techniques under current development for ingot casting, it would no longer be necessary to make large capital investments in primary rolling equipment, the sole purpose of which is to reduce ingot castings to a form rollable on finishing mills. The results reported in the continuous casting of non-ferrous metals and specialty steels indicate that in addition to avoiding the primary rolling mills there is some basis for expecting significant improvements in yield, surface, and internal quality. Recognizing the shortcomings of the conventional procedures, the Inland Steel Co., in cooperation with Atlas Steels Ltd. and the Freyn Dept. of the Kop- pers Co. Inc., embarked upon a program to evaluate certain aspects of continuous casting in order to determine whether the process could be applied practically to an existing integrated steel plant producing 'large tonnages of carbon steels. TO assist in this evaluation a study was carried out in which several types of low carbon steel were continuously cast in an existing machine. It is the purpose of this paper to review some of the results obtained in the casting studies and to interpret the information that was obtained so as to indicate factors that must be considered in assessing operating limitations and plant capacities. Despite the early interest in the continuous casting of steel, the actual application to the steel industry is relatively recent. At present, there are about 25 operating plants casting steel, most of which have been built in the past decade. None of these plants could be classified as large in terms of the tonnages that are being processed by the major integrated steel plants. In contrast to the situation in the steel industry, there has been widespread adoption of the continuous process in the casting of nonferrous alloys, particularly aluminum and copper. As a result, much of the basic information that was required to apply the process to steel was developed in the nonferrous industries. In this respect, a most important contribution was the development of the Junghans2 system, which was initially designed for the casting of nonferrous metals and later applied to the casting of steel. Alternative methods for casting have also been proposed by Babcock and Wilcox Tube Co.,'" the British Iron and Steel Research Association,5 and the Gebruder Bohler A. G.13 Each of these methods is now being used successfully for the casting of special steels in small experimental plants or in modest sized commercial steelworks. The Original Junghans process was first developcd in Germany. Further application of the process has been made by Rossi in other countries.'*' The experi-

Jan 1, 1958

By Kenyon E. Richard, James H. Courtright

Thomas W. Mitcham (Strategic Minerals, Inc., Grand Junction, Colo.)—The authors have presented a significant contribution to the field of mining geology. The article is graphic, remarkably concise, and crisply original. The presentation is made on only three pages with two maps, but their Silver Bell story is entirely adequate in background, development, and conclusion. Most of their colleagues would agree that this paper reflects the high quality of the work which these unusually capable men have done in the Silver Bell area over the past few years. The Silver Bell area is one of complex tectonic structure, and time and spatial relationships are by no means apparent. Actually, most of the observations and interpretations in this paper are new to published geologic literature on the Silver Bell area. I am in agreement with these interpretations with two possible exceptions, which are discussed below. One might well define the three roughly parallel west-northwest faults, shown on the insert of Fig. 2, as the major structural elements of the area. North to south, I propose that these be named the Ragged Mountain fault, the Silver Bell fault zone, and the Waterman thrust, after the mountain ranges which are the results of these major structures. While I would agree with the authors that the northern two of these major structures are high-angle faults of the Laramide revolution, my impression is that the southern structure is a low-angle thrust of approximately Miocene age. In support of this opinion, I submit the following observations: 1) irregularity of the fault in strike; 2) scarcity of Laramide intrusives and alteration of sediments along the fault; 3) present high re- lief of the Waterman Range which indicates youth or certainly rejuvenation; and 4) existence of a series of parallel structures farther to the south which results in an outcrop pattern suggesting imbricate thrusting. The authors have stated that Laramide igneous activity began with the intrusion of alaskite. Some dacite flows appear to be conformable with Cretaceous beds, and thus my impression was that alaskite followed the intrusion and extrusion of dacite. I would be interested to learn of evidence in support of the reverse relationship suggested by the authors. Kenyon Richard and J. H. Courtright (authors' reply)—The authors appreciate Mr. Mitcham's attention to this paper. The names he proposed for the major faults seem appropriate. His suggestion that the Waterman fault is a thrust may be correct because he did more work in that particular area than the authors. However, it is believed that no direct evidence of a low-angle thrust relationship has been recognized, and the authors consider that indirect evidence favors a high-angle fault interpretation. The pre-dacite flow age of the alaskite is definitely established, the authors believe, by the fact that the flows rest on an erosion surface which was carved in the dacite porphyry, an intrusive clearly younger than the alaskite, as evidenced by inclusions of alaskite occurring in dacite porphyry. No direct evidence of Cretaceous sediment-flow rock relationships was found at Silver Bell, but in the nearby Tucson mountains dacite agglomerates, megascopically similar to those at Silver Bell, overlie a basal conglomerate which in turn rests on the truncated edges of steep-dipping Cretaceous arkosic beds.

Jan 1, 1956

By T. Fraser, R. L. Sutherland

Under a cooperative agreement between United States Bureau of Mines and the Truax-Traer Coal Company, some operating-scale experiments have been made with the cyclone thickener in the preparation plant of the Shamrock No. 1 mine at Kayford, West Virginia. These tests were made with a 14-in. cyclone of the type developed by the Dutch State Mines in Limburg. It was applied experimentally to the thickening of solids in washery water to obtain performance data to show the range of sizes that may be recovered and other operating characteristics that would indicate the field of usefulness of this device in coal preparation practice. This is a progress report only. It covers results obtained in a series of 17 tests of the operation of what has been considered a unit of commercial size operating on suspensions of fine coal mixed with a relatively small amount of freeimpurities. The underflow material, after further dewatering in centrifuges, is a marketable grade of coal.

Jan 1, 1949

By H. W. Gillett

BATTELLE Memorial Institute is an endowed in stitution for scientific research in metallurgy, fuels, and allied fields, established by the will of Gordon Battelle, 2nd, as a memorial to his father, Colonel John Gordon Battelle. Before I tell you more of what Battelle Memorial Institute is, I want to go back a bit and tell you why it is. Colonel Battelle began his services in the iron and steel industry in Wheeling in 1866 and in 1883 came to Ohio, where he successively engaged in the iron and steel industry in Cincinnati, Piqua and Columbus. The family had been prominent in Ohio affairs since 1788, when Gordon Battelle's great-great-grandfather came from New England to settle in Marietta. He was one of the pioneers and a member of the famous "Ohio Company."

Jan 1, 1929

By AIME AIME

L. C. GRATON, professor of geology in Harvard University, addressed the New York Section on April 24 on-his impressions of the Rand. His beautifully clear and concise address was delivered without notes, so that what follows is merely a resume of the principal points made. The world is apparently coming to the end of ore discoveries easily made, yet we need metals at a steadily increasing rate. If surface discoveries are to decline, then we must find other ores or use less metals. The probable chances of finding ore are greater in the centers of big production than in new districts, as proved statistically. It is unsafe to say that a field is worked out. Therefore, deep mining holds possibilities and is an interesting study that will progressively gain in importance. The origin of the gold in the banket of the Rand has been a geologic football for a long time. Of the various theories, two have survived: 1. Infiltration into permeable conglomerate beds from deep-seated sources; 2. the placer hypothesis, which holds that gravel beds originally had the gold in them. At present, the second theory is accepted by the majority, as a result of the studies by the Union Geological Survey and by E: F. Mellor which were published about fifteen years ago.

Jan 1, 1929

By AIME AIME

MEXICO embraces one of the great metal and petroleum producing provinces of the world. In this respect its history dates back to the overthrow of the Aztec empire by a Spanish force under Hernando Cortes between 1519 and 1.521. Even before then, its richness in silver and other minerals was not unknown. But it was a treasure house for the Spanish conquerors until the country became independent in 1821. It has been computed that in the 400 years following 1521, Mexico yielded 1.55,000 metric tons of silver, worth $3,000,000,000, two-thirds of the entire world production. In 1935 the country accounted for 36 per cent of the world's silver output, 14 per cent of its antimony (in 1934), 13 per cent of its lead, 3 per cent of its zinc and copper, and 21/2 per cent of its petroleum. Contrary to the impression of some, its gold output is now comparatively small, though important in the past. Its oil, as well, formerly hulked much larger than now, in 1921 being one-fourth of the world output.

Jan 1, 1936

By A. CHESTER BEATTY

MAGNESIUM oxide is by far the most refractory of the common oxides, since it has a melting point of 5072 deg. F. as compared with 3110 deg. F., the melting point of silica (crystobalite) ; 3722 deg. F., the melting point of alumina (corundum) ; and 4127 deg. F., the melting point of chromite (Cr2O33FeO). Its large-scale use in the lining of metallurgical furnaces dates back to the latter part of the nineteenth century, when extensive deposits of magnesium carbonate were discovered in southern Austria in the province of Styria. Before the development of Austrian magnesite, calcined dolomite, a mixture of lime and magnesia, was used in basic steel-making furnaces. The lime in the dolomite was quite objectionable, since it slaked on exposure to the atmosphere, and dolomite therefore could not be made' .into permanent furnace bottoms or into brick. The Austrian magnesite, with its very low lime content, was free from these objections and soon displaced much of the dolomite. With the extensive development of basic steel-melting, the rise of the copper industry, and other metallurgical and chemical processes which dealt with chemically basic substances, the use of magnesite grain and magnesite brick increased rapidly.

Jan 1, 1931

By Frank Milliken

IN September 1937, the Ohio Copper Co. inaugurated the treatment of its copper-bearing mill tailings at Lark, Utah. These tailings had been accumulated during the regular operation of the Ohio Copper mine and mill over the period 1007 to 1019. Gravity concentration had been employed except for a comparatively short period in 1919, when flotation was used. The ore milled during that period assayed about I per cent Cu. The chief copper mineral, chalcocite, was dissemi-nated in a shattered quartzite, mainly along fracture or cleavage planes. The quartzite gangue was extremely hard and grinding to liberation resulted in excessive sliming of the "sooty" chalcocite, with consequent high tailings losses. Recovery on the seven million tons treated was prob-ably less than 6o per cent of the total copper content. As early as 1918, attempts had been made to sample the dump. In 1928, a com-plete sampling program was undertaken. The sampling consisted of seventy-four 5-in. post auger holes drilled to the full depth of the dump at regular intervals of 250 ft. Each 10-ft. portion thereof com-prised a sample for analysis. Each sample was screened, rolled, divided into three parts, dried and assayed. The reject was retained for testing purposes. From the depth of the auger holes a contour map of the dump was plotted, Fig. 1, which gives percentages of tonnage and copper content.

Jan 1, 1940

By Culver, Richard S.

In spite of the widespread interest in rock bolt research, relatively little is known about the critical region surrounding the bolt anchor. In analyzing the stress distribution around an opening resulting from rock bolt support, it is commonly assumed that the bolt is fixed at a point far enough from the surface so that the anchor does not influence the performance of the bolt. Furthermore, a bolt anchor is assumed to per- form satisfactorily if it will hold the design load with a minimum amount of load relaxation, commonly called bleedoff. From the standpoint of the design engineer both of these assumptions are reasonable, but they ignore the fact that the extremely high stresses in the region of the anchor are capable of generating fractures in the rock. Lang estimated the bearing stresses for a slot and wedge anchor on a one-inch-diameter bolt to be as high as 125,000 psi. This paper describes a more thorough analysis of the magnitude of the stresses around the anchor and the nature of the potential fractures that might result.

Jan 1, 1968

By Arthur Glance

MINE safety is of the utmost importance to all operators and most operations have a safety organization, or safety inspector, whose job it is to be continually on the alert to detect and correct the hazards of mine operation. Reports from the Bureau of Mines show that next to roof falls, gas presents the greatest hazard in mining. The Bureau of Mines Information Circular 6680 shows that 162 explosions occurred in the United States during the five-year period ending June 30, 1932. Deaths resulting from these explosions amounted to 984, with a great many disabled and disfigured. A fatality rate of 6.07 persons shows the ex¬treme severity of this hazard to the industry. Various mine appliance companies have put on the market instruments for methane detection, which record in direct percentages the amount of methane present in the atmosphere. Unfortunately, few mining companies are using these instruments, however. Those available include the Burrell methane detector, the Wolf, the Martienssen, the Mine Safety Appliance detector, and the Union Carbide Company methane detector, which last I have used extensively in making mine inspections.

Jan 1, 1936

Albert Arents, Alameda, Cal.: From Mr. Furman's description of his crucible-assays I infer that he regards iron nails as a necessary or advisable adjunct. Against such a notion I must beg leave to protest. Nails should not be used in

Jan 1, 1896

By W. C. Meyer

In an effort to conserve and extend oil resources, the use of powdered coal-in-oil mixtures (COM) as an alternate fuel in oil-fired boilers is receiving increasing attention. For the approach to be successful, some degree of stability of the suspension against settling is needed. The variety of means available to achieve stability of this nonaqueous slurry is reviewed along with some of the physical and chemical concepts which underlie each method.

Jan 1, 1983

By M. E. Lombardi

Discussion of the paper of AI. E. LOMBARDI, presented at the San Francisco meeting, September, 1915, and printed in Bulletin No. 105, September, 1915, pp. 2109 to 2114. C. D. KEEN, Shreveport, La.-Did Mr. Lombardi include in his figures the purchase price of the property? M. E. LOMBARDI, Berkeley, Cal.-No. C. D. KEEN.-Suppose I pay $1,000 per acre for it, and in four or five years it is worked out. M. E. LOMBARDI.-That is a question of depreciation and must be added to my figures. MARK L. REQUA, San Francisco, Cal.-You say it cost $35,000 to $40,000 a year to maintain 1,000-bbl. per day production? M. E. LOMBARDI.-Yes, 1,000 bbl: a day would cost $40,000 a year to maintain.

Jan 12, 1915

By Henry J. Kaiser

A few months ago I had the honor of addressing the Society of Mining Engineers annual banquet in Sun Francisco. I have since been asked to amplify some of the remarks I made at that time concerning the management policies of the Kaiser organization and various aspects of our corporate thinking. This is a difficult task for an insider like myself. I look at the different companies, and the men who run them, and it is hard to think of these men in terms of policy or procedure. Actually I prefer the term management philosophy to either policy or procedure. My father, Henry J. Kaiser, is not only the founder but the guiding spirit of our organization. His philosophy, and in turn that of the organization, centers around two concepts, service and accomplishment.

Jan 1, 1960