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Gardner I?. Williams, authority on diamond mining, died at San Francisco, Cal., on Aug. 22, after an illness of nearly a year. Mr. Williams, who was in his eighty-first year, was born in Saginaw, Mich. He was graduated from the University of California in 1865, and afterward took a course at the Freiberg Mining Academy in Saxony. He was awarded the degree of LII. D. by the University of California in 1910, and Doctor of Engineering by the University of Michigan in 1917. Beginning in 1870, Mr. Williams spent two years as assistant assayer at the United States Mint in San Francisco. He successfully developed

Jan 1, 1923

By T. E. Schwarz

The publication of the report by Mr. F. L. Ransome1 was welcomed by many engineers who had mined in the heart of the San Juan country, braved its long and snowy winters, climbed its lofty peaks, run the gauntlet of its snow-slides, and studied its problems of geology, while making dividends for their English or American clients. This report helps one to understand why the bonanzas occurred, and why the inevitable " borrasca " presents itself where least expected. The Red Mountain district of Ouray county, a very productive section from 1884 to 1893, occupies considerable space in the report mentioned. The character of the ore-occurrence.

Jan 1, 1906

By F. H. McDowell

About a year ago Dr. Raymond, as engineer of Messrs. Cooper, Hewitt & Co., together with Mr. Rothwell, was considering the removal of the ore-floors and pillars from the Peters Mine at Ringwood, N. J., where the limit of profitable working by the old method of mining had been very nearly reached. Mr. Ferdinand Ruttmann was engaged to make the survey which forms the basis of the accompanying diagrams. At first it was thought that some method of mining and filling might be introduced with advantage; but after a careful study of the operations at the Tilly Foster it was decided to adopt the system of stripping.

Jan 1, 1890

By John V. Beall

Beall: Mr. Bennett, you have had a very successful -and a very colorful-career in mining. Would you tell us about your first job in the mining industry? Bennett: I was a mine surveyor on the Mesabi and Marquette ranges, working both open pit and underground. I worked two years for the Meriden Engineering Co., formerly the Meriden Iron Co., which was founded in 1904 to operate mines and to act as a lessors' agent for inspection. At the time I was there, Meriden was operating one open pit and one underground mine, and acting as agent or inspector for some lessors, the owners of the fee interest.

Jan 1, 1968

By J. E. Lawver, W. D. Carrier

During the past 20 years, millions of dollars in research effort have been spent to improve methods of phosphate clay dewatering and disposal. Although to date no proven large-scale system has been developed that will result in ultimate below ground storage without the use of at least temporary dams, considerable progress has been made and a variety of techniques are being tested, some on a large scale. This paper summarizes the use of mathematical and centrifuge (physical) models that can analyze and evaluate various systems for the consolidation of phosphatic clays. These provide a powerful tool for engineers responsible for land management and mining waste disposal.

Jan 1, 1985

By G. M. Ritcey

The concentration of metals in the solution, the .value of the metal being recovered, together with the flow through- put, may singly or in combination conbribute to the decision on the possible use of solvent extraction. Also, as noted earlier, the upstream and downstream aspects of the overall process have to be considered. The economic considerations may be divided into: 1. Capital investments 2. Operating costs Capital Cost The capital costs can be influenced by the following: 1. number of stages; 2. kinetics; 3. coalescence; 4. entrainment; 5. flow rates and ratios; 6. building requirements; 7. ancillary equipment; 8. environment constraints or requirements; 9. engineering design.

Jan 1, 1978

NEW MEMBERS The following list comprises the names of those persons who became members during the period Feb. 10, 1916 to Mar. 10, 1916. ALLAN, FERGUS L., Min. Engr., Cons. Min. Engr., Mexico Mines of El Oro, El Oro, Mex. ARMSTRONG, EMERSON WARREN, Met.,. Mina Bibilonia, La Libertad, Nicaragua, C. A. BABB, P. A Blaisdell Coscotitlan Syndicate, Pachuca, Hgo., Mex. BANDY, PERCY J Fundicion Delicias, Calle Delicias, Mexico, D. F. BELLWALD, J. N Apartado 1488, Mexico, D. F. BILLICK, DON CARLOS, Min. Engr., Supt., Hess Gold Mines Co., Alturas, Modoc Co., Cal. BITLER, FRANK L., Cons. Min. Engr., Birkinbine Engineering Offices, Parkway Bldg., Broad and Cherry Sts.. Philadelphia. Pa.

Jan 4, 1916

OUR 78th Annual Meeting was, technically and attendance-wise, one of the greatest to date. No one who came to New York's Hotel Statler had time to hear all 266 papers, or to attend all 70 sessions and 27 committee meetings, or to shake the hands of the more than 3000 engineers, educators, students and executives who attended-but no one was lost in the crowd. For crowds always dwindle down to groups of two and three and four, and those are the little sessions which make our meetings well worth attending. Herewith four pages of photographic highlights and sidelights on the February gathering.

Jan 3, 1950

Frank Owen, El Perú Venezuela (communication to the Secretary): Mr. Cragoe's accurate description of the rich and extensive mines of the Frontino and Bolivia Co. is of much interest to those acquainted with Colombian mining. While the labor in that part of Colombia is, of course, admittedly far inferior to that of white miners, it is,. nevertheless, decidedly superior to that available in other parts of the republic, and in the northern mining regions of South America generally. The Autioquenos have been miners for several generations, and many of those employed at the Frontino Co.'s works have been brought up at the mines, which is a distinct advantage. The ground encountered in the surface-workings of that district being very treacherous, they are skillful timber-men, every miner being able to put in his own timber in tunnels, stopes, etc., so that, except for the main shafts, where sawn timber is used, special timber-men are not required. In the shallow workings it is the custom for a miner to come out of the mine into the thickly-wooded bush and select and cut the timber he requires, which he will then take into the mine and put in

Jan 1, 1899

By Benjamin Smith Lyman

It is a time-honored saying in the anthracite region that " under the conglomerate there is no coal;" and the adage is generally reckoned a sure guide in coal-exploration. Yet there are many places where conglomerate, even coarse conglomerate, occurs above important coal beds, and, among others, above the great Mammoth bed. One of the most striking of such occurrences is on the Shippen and Wetherill tract, half a dozen miles west of Tamaqua; and it illustrates remarkably the disastrous effect of a too unquestioning blind confidence in the sweeping literal truth of a broad generalization. Here there is a conspicuous crag formed by a twenty-foot bed of egg-conglomerate, dipping 60 degrees southerly, and jutting out boldly at the western end of a hill, where it is cut through by the small stream of Little Creek. The hill runs eastward for half a mile, with occasional exposures of pebbly rock along the western half of the crest. Eastward from the exposures lies the old Kentucky Bank mine, abandoned thirty years ago, where the Mammoth bed was worked down to water-level through a space of a mile and a quarter westward from the Palmer tunnel to the very edge of the

Jan 1, 1893

By C. F. Jr. Tolman

IN February 1913, Prof. L. C. Graton and Dr. Joseph Murdoch1 presented to the American Institute of Mining Engineers a notable contribution to economic geology under the title The Sulphide Ores of Copper. The value of the work was recognized by mine operators, and Mr. Graton was assisted in his plan to extend his investigations,. by the organization of a commission to undertake a "secondary enrichment investigation." In this work lie secured the cooperation of the Geophysical Laboratory of the Carnegie Institution of Washington. Their report 2 on the chemical phases of the investigation has just been published. Incidental to investigations 3 carried on in my laboratory by advanced

Jan 2, 1916

By Paul T. Allsman

Passage of the Mining Act of 1866, superseded by the Act of 1872, was the first major entry of the Federal Government into the problems of mining. Such a law was necessary simply to help re- solve a number of disputes in mining. Now, however, a hundred years later, the extent of government involvement in the mineral industry often comes as a shock to the mining engineer who has reached management level. In fact, he has been poorly prepared for an understanding of the role of government in the industry and he becomes frustrated, even hostile. In our political system, private industry is responsible for producing minerals and the Government sees to it that production will be adequate for a peace-time economy and for any emergency. There have been great social and political changes since World War I1 with the result that the Government's participation in our society has steadily increased. A new dimension in business and government relations has been introduced which should be examined more closely.

Jan 5, 1966

By Harry R. Cedergren

Properly designed drainage systems can be of great benefit to many kinds of Civil Engineering works, including embankments, and often are the most economical way to protect such works from the damaging effects of water. To function properly, drains must be able to remove water without also removing soil or becoming clogged with soil or erodible rocks. The first criterion to be used in designing drainage systems, called the filter criterion, can prevent all such problems (erosion and clogging) when properly fulfilled in design and construction. The second requirement of drains is that they must be capable of removing all of the incoming water without the build-up of large amounts of head that can damage the protected works. To insure this kind of perfomance, the discharge capabilities of drains should always be verified by appropriate hydraulic and seepage calculations. This paper describes these two basic drain design criteria and also gives examples of application of seepage principles to the evaluation of the potential benefits of drains and to the design of drains for mine waste embankments.

Jan 1, 1985

By Clarence Zener

Contents Page General Principles................................................................. 551 Equilibrium Diagrams......................................................... 551 Nucleation................................................................... 553 Kinetics of Phase-boundary Propagation......................................... 553 Kinetics of Growth of New Phase............................................... 556 Spheroidization............................................................... 560 Pure Iron-carbon System........................................................... 561 Formation of Pearlite.......................................................... 561 Interlamellar Spacing........................................................ 562 Pearlite C-curve............................................................. 563 Bainite Formation............................................................. 565 Formation of Martensite....................................................... 570 Loss of Tetragonality of Martensite.............................................. 570 Effect of Alloys upon Decomposition of Austenite..................................... 572 Pearlite...................................................................... 572 Bainite and Martensite......................................................... 574 Time-temperature-transformation Curves............................................. 576 Appendix A............................................................. ......... 579 Appendix B....................................................................... 580 Appendix C....................................................................... 580 The present investigation started in an attempt to understand certain details of the decomposition of austenite, and of the effect of alloying elements thereon. As the investigation proceeded it became apparent that not only these details, but all the general features of austenite decomposition, could be understood in terms of fundamental physical principles. Since the direct applicability of these physical principles has not been previously recognized, it was decided to incorporate the original results of the investigation into a review of the general subject of the kinetics of austenite decomposition. This review constitutes the present article. An extended summary of the results is given on pages 576 to 579. This article, which deals with the kinetics of phase transformations, may appropriately be considered as a sequel to two recent articles1,2 from this laboratory on the equilibrium relations in medium alloy steels.

Jan 1, 1947

By Clarence Zener

Contents Page General Principles................................................................. 551 Equilibrium Diagrams......................................................... 551 Nucleation................................................................... 553 Kinetics of Phase-boundary Propagation......................................... 553 Kinetics of Growth of New Phase............................................... 556 Spheroidization............................................................... 560 Pure Iron-carbon System........................................................... 561 Formation of Pearlite.......................................................... 561 Interlamellar Spacing........................................................ 562 Pearlite C-curve............................................................. 563 Bainite Formation............................................................. 565 Formation of Martensite....................................................... 570 Loss of Tetragonality of Martensite.............................................. 570 Effect of Alloys upon Decomposition of Austenite..................................... 572 Pearlite...................................................................... 572 Bainite and Martensite......................................................... 574 Time-temperature-transformation Curves............................................. 576 Appendix A............................................................. ......... 579 Appendix B....................................................................... 580 Appendix C....................................................................... 580 The present investigation started in an attempt to understand certain details of the decomposition of austenite, and of the effect of alloying elements thereon. As the investigation proceeded it became apparent that not only these details, but all the general features of austenite decomposition, could be understood in terms of fundamental physical principles. Since the direct applicability of these physical principles has not been previously recognized, it was decided to incorporate the original results of the investigation into a review of the general subject of the kinetics of austenite decomposition. This review constitutes the present article. An extended summary of the results is given on pages 576 to 579. This article, which deals with the kinetics of phase transformations, may appropriately be considered as a sequel to two recent articles1,2 from this laboratory on the equilibrium relations in medium alloy steels.

Jan 1, 1947

By Jack A. Simon, M. E. Hopkins

GENERAL GEOLOGY Coal is defined as a combustible rock that had its origin in the accumulation and physical and chemical alteration of vegetation. Coal can be ignited and burned like the wood that was man's earliest fuel, but coal gives more heat than the same amount of wood and has many industrial uses. Unlike wood, coal is not generally found on the surface of the ground but is mined from the solid rock of the earth. Before taking up the occurrence, formation, and the somewhat unique character of coal in the rock sequence, let us briefly consider the general character of all rocks in the crust of the earth. Relatively little is known about the very earliest history of the earth, although a number of logical theories have been developed. Manned exploration of the moon and the rocks being returned to earth will, we hope, provide some answers to questions concerning the earth's origin and history. The period of earth history with which we concern ourselves here begins after great areas of water had evolved on earth and substantial land areas of once molten (igneous) rock existed. Weathering and other processes that attacked the surface of the rocks reduced them to small particles. Water provided by rainfall transported this material, ultimately, to large bodies of water where it was deposited. Thus was initiated the geologic sequence of sedimentary rocks that lie above the once molten igneous rocks. The crust of the earth is not completely stable, and throughout the geologic past portions of the crust have moved laterally and vertically. Even today, many coastal areas are slowly rising or sinking. More sudden earth movements are recognized by the earthquakes they cause. Throughout geologic history, rises in sea level or the sinking of the land areas have many times permitted the oceans to cover much of what are now the areas of the continents. Only relatively small parts of the present continents appear to have been above sea level throughout geologic time. Great

Jan 1, 1973

IN the preceding chapter on thermochemistry and the reactions in and between metal and slag phases and in the following chapter on fuel combustion the main emphasis is placed on the equilibrium or "static" conditions. This equilibrium viewpoint is not concerned with the rate of change in the process or with the mechanisms or paths followed between initial and final states. The questions of just "how it works" and "how fast" belong to the kinetic aspect of any process; their answers are helpful in speeding up or slowing down and thus controlling its operation, and also in understanding its limitations. Any treatment of kinetic factors in the open hearth such as is attempted here and in Chapter 22 must at present be largely qualitative and incomplete. We are only beginning to get quantitative data on rates of reaction and diffusion at high temperatures, as indicated in Chapter 15. Empirical data in the literature on furnace operating rates do not help much to illuminate the details of gas-flow patterns and the complexities of heat flow in the many parts of the furnace system. This chapter is intended to give the reader an introduction to the problems of the flow of gases through the furnace system and the flow of heat in this system. An adequate discussion would require several times the space available here; it is possible here only to outline a few fundamentals and to indicate some of the conditions of heat and gas flow peculiar to the open hearth. Several good general treatments of these subjects may be found in the literature (see references at the end of the chapter). For the designer of open-hearth furnaces, the principles of gas flow are of paramount importance. They are also important to the operation of the process, at least to the extent of a general qualitative picture of the movement of gases in the system. MOTION OF GASES IN FURNACE DUCTS Fluid flow in general can vary between the extremes of laminar or streamline flow with a minimum energy loss, to irregular

Jan 1, 1951

IN the preceding chapter on thermochemistry and the reactions in and between metal and slag phases and in the following chapter on fuel combustion the main emphasis is placed on the equilibrium or "static" conditions. This equilibrium viewpoint is not concerned with the rate of change in the process or with the mechanisms or paths followed between initial and final states. The questions of just "how it works" and "how fast" belong to the kinetic aspect of any process; their answers are helpful in speeding up or slowing down and thus controlling its operation, and also in understanding its limitations. Any treatment of kinetic factors in the open hearth such as is attempted here and in Chapter 22 must at present be largely qualitative and incomplete. We are only beginning to get quantitative data on rates of reaction and diffusion at high temperatures, as indicated in Chapter 15. Empirical data in the literature on furnace operating rates do not help much to illuminate the details of gas-flow patterns and the complexities of heat flow in the many parts of the furnace system. This chapter is intended to give the reader an introduction to the problems of the flow of gases through the furnace system and the flow of heat in this system. An adequate discussion would require several times the space available here; it is possible here only to outline a few fundamentals and to indicate some of the conditions of heat and gas flow peculiar to the open hearth. Several good general treatments of these subjects may be found in the literature (see references at the end of the chapter). For the designer of open-hearth furnaces, the principles of gas flow are of paramount importance. They are also important to the operation of the process, at least to the extent of a general qualitative picture of the movement of gases in the system. MOTION OF GASES IN FURNACE DUCTS Fluid [flow] in general can vary between the extremes of laminar or streamline flow with a minimum energy loss, to irregular

Jan 1, 1964

By John A. Gann

The following investigation constitutes a brief réumé of the more important binary magnesium alloys from the standpoint of metallo-graphic technique, and the effect of heat treatment on structure and properties. The comparative newness of the subject justifies this procedure as a preface to a more detailed study of each individual series of alloys. The work was started with the idea of practical application in the industry rather than as a theoretical investigation. The alloy compositions studied were selected as those most likely to show whether heat treatment would produce beneficial results. Furthermore, it was considered satisfactory to use commercial 99.9 per cent. magnesium, the best commercial grade of alloying ingredients, and to limit the time of heat treatment at the expense of incomplete equilibrium. These facts must be kept in mind when examining the results obtained, and the conclusions drawn. Preparation of Alloys All melts were made in an oil-fired cast-steel pot, approximately 12 in. dia, by 12 in. deep. Approximately 15 lb. of flux and 50 lb. of magnesium were melted and the calculated amount of alloying metal was added. After thorough alloying and puddling, the metal was chill cast in a graphite mold with four 1/2 by 1/2 by 4 in. bars fed from a common sprue and runner. The next higher composition alloy in a given series was made by adding the calculated amount of metal to the heel from the preceding cast. The pot was thoroughly cleaned after each series and new flux then introduced, thus avoiding possible contamination from earlier melts. The percentage compositions given in Table 1 are the calculated values. While not all alloys were analyzed, enough were checked to indicate that the reported compositions are correct to a few tenths of one per cent. A more detailed description of the foundry methods employed has been given in a previous paper. 1

Jan 1, 1929

By John A. Gann

The following investigation constitutes a brief réumé of the more important binary magnesium alloys from the standpoint of metallo-graphic technique, and the effect of heat treatment on structure and properties. The comparative newness of the subject justifies this procedure as a preface to a more detailed study of each individual series of alloys. The work was started with the idea of practical application in the industry rather than as a theoretical investigation. The alloy compositions studied were selected as those most likely to show whether heat treatment would produce beneficial results. Furthermore, it was considered satisfactory to use commercial 99.9 per cent. magnesium, the best commercial grade of alloying ingredients, and to limit the time of heat treatment at the expense of incomplete equilibrium. These facts must be kept in mind when examining the results obtained, and the conclusions drawn. Preparation of Alloys All melts were made in an oil-fired cast-steel pot, approximately 12 in. dia, by 12 in. deep. Approximately 15 lb. of flux and 50 lb. of magnesium were melted and the calculated amount of alloying metal was added. After thorough alloying and puddling, the metal was chill cast in a graphite mold with four 1/2 by 1/2 by 4 in. bars fed from a common sprue and runner. The next higher composition alloy in a given series was made by adding the calculated amount of metal to the heel from the preceding cast. The pot was thoroughly cleaned after each series and new flux then introduced, thus avoiding possible contamination from earlier melts. The percentage compositions given in Table 1 are the calculated values. While not all alloys were analyzed, enough were checked to indicate that the reported compositions are correct to a few tenths of one per cent. A more detailed description of the foundry methods employed has been given in a previous paper. 1

Jan 1, 1929