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By H. William Ahrenholz

The coal industry had another prosperous year in 1966. Since the turn of the decade, production has been climbing at an average rate of 6% per annum. Although the fast pace slackened somewhat, 1966 production showed a gain of almost 3 % over that of 1965. An impressive record can be drawn from the fact that output per man-day in 1966 was more than twice that of the early 1950's, and more than three times that of the early 1940's. And even though man-power requirements lessened, those men retained by the industry worked longer hours and benefited through higher hourly pay rates. However, cost to the customer increased a little. Such statements can only be made for a healthy industry -one that is constantly improving its efficiency. Coal currently provides more than 25% of the total U.S. energy output. About 50% of all U.S.- mined bituminous coal goes directly to the electric utility market. It should be noted that, now, well over one trillion kwh of electricity is generated annually. Dependence of the giant electric utility industry on coal is based on economy and an abundant, dependable supply of this fuel.

Jan 2, 1967

By Arthur S. Dwight

THE professional career of Thomas Septimus Austin, who died at El Paso, Tex., August 23, 1906, was contemporaneous with the growth of the silver-lead smelting-industry of the Far West, to which his talents and zeal contributed in no small degree. Born at Stratford, Conn., December 7, 1853, he was the seventh son in a family of thirteen. His parents were well-to-do; and he received a thorough preliminary training at the Hopkins Grammar School, New Haven, Conn., passing thence to the Columbia School of Mines, in New York, where he was graduated in 1876. His first professional work was that of analytical chemist with a Cuban sugar company. In this position he spent a year, and, whatever else of benefit he may have acquired during that year in Cuba, he gained a facility of speech in the Spanish language which was of inestimable value in his subsequent work in Mexico and the southwestern United States. In 1877, he went to the Rocky Mountains, and, under the firm name of Murphy & Austin, opened an assay-office in Leadville, Colo., which was just then coming into public notice as a rich silver-lead camp. The next year, however, he entered the service of the Germania Smelting & Refining Co. at Salt Lake City, Utah, where he remained until 1882, first as assayer and chemist, and later as Assistant Superintendent. The Germanic bears the honorable distinction of being one of the first of the large " custom " lead-smelters erected in the West. Its founders may be called the pioneers of the modern lead-smelting practice, and the Germania served, to a large extent, as a model for the many plants that sprang into existence during the next few years in Utah, southern Idaho, Colorado and other lead-producing districts. The formulation, for the first

Jan 1, 1908

By Juanito C. Fernandez

INTRODUCTION The Philippines is endowed with mineral resources, much of which still remains unexploited. The country's known reserves, at least for the major mineral commodities, have increased every decade since the first major discoveries more than 80 years ago. Mining, therefore, naturally evolved as one of the pioneer industries and has ever since been a major factor in economic development. The Philippines has entered a new era in mineral resources development and management. One significant feature of this era is the degree to which the government is involved with the industry. In recent years, the state has increasingly encouraged the private sector to carry out detailed exploration aided by governmental contributions through extensive geological and geophysical surveys, fundamental researches and even indirect financial assistance in some specific areas. Significant changes in mineral resources development policies were brought about with the promulgation of Presidential Decree 463 or the Mineral Resources Development Decree of 1974. The Decree provides for a more rational system of administration and disposition of mineral lands to promote mineral resource exploration and exploitation. Various forms of incentives are provided. Foreign entities are allowed to participate in development through service contracts with leaseholders or with the government in the case of reserved areas. The thrust in mineral resources development has been focused on the base metals which as envisioned would provide the foundation for sound economic development. In recent years, however, major strides have been made to promote the exploitation of the non-traditionally produced commodities especially the non-metals. Development likewise point to the growing determination of the government and the private sector to expand benefits from mining. This is evident in efforts to promote downstream processing operations and to encourage investments in exploration, exploitation and mineral processing ventures. The integrated mineral resources development plan, therefore, proposes the vertical integration of mining extraction activities with the processing requirements of the metal-based manufacturing industries. While mining activities shall continue to be carved out by the private sector, the government shall influence the industry's direction by establishing legitimate goals to maximize benefits through an integrated approach giving due consideration to environmental protection and resource needs of future generations. STATUS OF MINERAL RESOURCES DEVELOPMENT Extent of Exploration Application of modem exploration tools and concepts complemented by intense infusion of foreign technology and rapid development of indigenous expertise have enabled the government jointly with the private sector to geologically explore vast grounds and to expand the country's known mineral resources. Approximately 93% of the country's total land area of 30 million hectares have been geologically mapped on at least 1:250,000 scale. Of the 93% total coverage, roughly 37.54% or 11.07 million hectares have been done on scales of 1:10,000 to 1:50,000 as shown in Figure I. Only 3.07% of the total coverage have been surveyed in detail. Land gravity surveys have been undertaken on over 45% of the total, while some 77,300 line km. of aeromagnetic surveys have been flown over 110,000 sq. km. of land area. Processing of data is almost complete. Total magnetic intensity and IGRF-corrected maps are available. Geological interpretation utilizing Landsat MSS imagery and low altitude aerial photography augmented by ground truthing have been undertaken in several large areas with very encouraging results. Beach and offshore mineral surveys were initiated in 1977 and have covered substantial areas in northwest and southeast Luzon and northeastern Mindanao. Highly promising areas for detrital magnetite, chromite, gold and some heavy minerals including ilmenite and titanium have been identified. In the petroleum sector, two offshore oilfields are currently producing from Miocene limestone reefs in Northwestern Palawan. Another field from the same area will be on stream in mid-1982.

Jan 1, 1982

By William Campbell

(Cleveland Meeting, October, 1912.) THE structure of iron and steel, though the object of so much study and research for the past 25 years, is by no means thoroughly understood. In the first place, we have three or more distinct iron-carbon thermal diagrams, each with its own supporters, and each representing a theory of the structure and constitution of cast-iron. In the second place, by reason of the fact that austenite, the solid solution of carbon in iron, decomposes in the solid state into ferrite, or pure iron, and cementite (Fe3C), and that quenching from above this transition-range, no matter how rapid, cannot entirely prevent the change and thus preserve the austenite by itself at ordinary temperatures, it happens that under the microscope we find, in addition to the ferrite, Fe3C, and austenite, which the thermal diagram of steel requires, it series of transition-products with distinctive structures, to which have ,been given the names martensite, troostite, sorbite, etc. Now these transition-products, in addition to the solid solution, austenite, have been the source of much controversy, at times very bitter. One side would insist that, say, troostite was an entity, which the other side would deny, pointing out that it must be a transition-mixture, with a particular structure. That austenite was a solid solution of carbon in iron has been denied by one school ; we have been told that Fe24C dissolved both Fe3C and Fe, and thus gave rise to a whole series of quenching-products-all this in spite of the fact that no matter how the thermal diagrams differ in regard to cast-iron, they all agree in regard to the solid solution, austenite, for Fe24C finds no place on the diagram. Thus it happens that while the authorities fight both in regard to the iron-carbon diagram and the structures met with in hard- * Associate Professor of Metallurgy, Columbia University in the City of New York.

Dec 1, 1912

By M. Dayne Aldridge

A discussion of the definition of automation in mine ventilation applications is presented. The results of theoretical studies, experiments, and practical experience from work in the United Kingdom, Belgium, Poland, the Soviet Union, and the United States are summarized Conclusions are drawn from these efforts and the prospects for the future development of automatic mine ventilation systems are explored.

Jan 1, 1980

By R. S. Bradley

WHAT are known as insulating firebrick are lightweight firebrick with low thermal conductivity designed primarily for use in direct contact with furnace gases. These are a recent development in the refractories industry, and are really an outgrowth of the type of insulating brick suitable for use behind refractory walls developed by the insulation manufacturers. To differentiate between these two types of brick, the manufacturers have recently agreed upon the use of the term "Insulating Firebrick" to apply to the type of brick suited for use in direct contact with furnace gases, and the term "Insulating Brick" for the type suitable for use behind refractory walls. Insulation was applied to steam pipes as far back as 1900. This was a low-temperature insulation, the most common type being magnesia blocks. The next development was applying insulation to the outside of furnace walls, a service which necessitated an insulating material of higher temperature resistance. Natural diatomaceous earth, both in the powdered and brick form, was used; this was efficient and is still used extensively for backing up refractory walls where the inner surface temperature of the insulation does not exceed 1600° F.

Jan 1, 1937

By J. G. Morlet, A. R. Troiano, H. H. Johnson

Delayed failure in steel occurs by controlled initiation and growth of a crack. The incubation period for crack initiation was measured. Crack initiation and Propagation are controlled by interaction between hydrogen concentration and triaxial stress state. The incubation period results from stress-induced diffusion of hydrogen to the point of crack initiation. THIS paper describes the phenomenon of delayed failureland the kinetics of crack initiation and propagation in uniformly hydrogenated steel. The investigation was prompted by service failures of high-strength-steel components at applied stresses far below the conventional yield strength, after the part had successfully sustained equal or higher stresses for an extended time interval. This delayed failure phenomenon, often termed static fatigue, is associated1 with the presence of hydrogen. This is not surprising, since the voluminous literature on flaking and hydrogen embrit-tlement demonstrates that hydrogen may exert a potent embrittling influence. Flakes, or internal hairline cracks in alloy-steel forgings, are related to the presence of hydrogen retained from the steel-making process.2 On the other hand, embrit-tlement arises from hydrogen introduced during surface treatments such as acid pickling or electroplating. Laboratory delayed failures have been induced in notch specimens of 4340 steel by electrolytic charging of the specimen surface with hydrogen and subsequent static stressing.l,4,5 Static fatigue was observed over a wide range of applied stresses; however, failure did not occur below a critical applied stress, designated as the static fatigue limit. In this instance the extended time for failure resulted primarily from the macroscopic redistribution of hydrogen. A crack formed to the depth of the hydrogen enriched "case* upon loading; further crack growth naturally awaited diffusion of hydrogen into the material ahead of the crack. The crack-propagation rate was therefore controlled primarily by the macroscopic diffusion of hydrogen into the specimen interior during the test. Thus, in this instance static fatigue was associated with the movement of a gross concentration gradient. However, delayed failure in steel of uniform hydrogen concentration is of greater fundamental interest, as well as commercial significance. With a homogeneous hydrogen distribution a different mode of delayed failure might be expected. As the heterogeneous hydrogen distribution became more uniform,4,5 the initial crack-propagation rate decreased markedly and, in fact, what appeared to be an incubation period for crack initiation was observed. However, the macroscopic concentration gradient precluded an accurate evaluation of these observations. Although the existence of an incubation period, up to this time, has not been established definitely, it is not amiss to point out some implications of the concept. It is of interest in all hydrogen-induced embrittlement phenomena, such as flaking, delayed failure, and hydrogen embrittlement. Much discussion has centered around the possibility of an

Jan 1, 1959

By AIME AIME

MOTHER example of the broad field that is covered by the mining industry is the recent erection by the Phelps Dodge Corp. of a modern hospital building at Douglas, Ariz., and an identical one at the rejuvenated mining town of Morenci. Managers of even small mining properties are often called upon to build schools, houses, stores, maybe a jail, and provide sanitary arrangements, possibly the while acting as mayor of the town. Those who direct larger properties may have to build hospitals, as in the present instance, construct sewage disposal plants, and sometimes even build and manage railroads. A mining camp achieves its reputation among mining men not entirely by the grade or amount of its ore, or the skill of the operating staff in mining and milling it at a profit-the operation soon acquires a reputation as either a desirable or an undesirable place to live, regardless of its remoteness from what is euphemistically termed civilization. Such a community is indeed fortunate if it can boast of a good hospital.

Jan 1, 1940

By George A. Hill

WE of the oil industry, devoted to freedom of initiative, free competitive enter- prise, and free American institutions, applaud, with one voice, affirmation by the President of the national will and purpose to preserve and to protect, against all aggressors, "our American way of life with our individual and national freedom." We subscribe utterly and completely to this guiding declaration and seek its further definition as applied to the oil industry. Fortunately for all, the policy of the Government, after adequate study and deliberation, has been given precise definition. The National Defense Advisory Commission, with its patriotic, highly qualified, and distinguished personnel, has unanimously agreed to and adopted twelve general principles governing national defense contracts and also fair labor standard requirements. The President of the

Jan 1, 1940

Jan 1, 1885

By Lawrence K. Nordell

This paper reviews practices used In the selection and sizing of belt conveyors and stacker systems commonly used in crushing and grinding plant facilities. Historical and modern methods of sizing this equipment are presented. The new methods Include: 1) probability theory applications for establishing component reliability, 2) "Monte Carlo" simulation techniques used in evaluating alternative system designs and in establishing service factors and corresponding availability Indices of each system, 3) quantifying the system and component operating characteristics using computer assisted modeling tools simulating rigid body and elasto-mechanic behavior for starting and stopping large and/or complex belt conveyors.

Jan 1, 1982

The Institute has prepared a list of Societies' publications, magazines, . etc., which were duplicates and were discarded at the time of the consolidation of the libraries of the three Founder Societies. These books will be disposed of about March 1, 1916 by the Board of Directors of the Institute through the Library Committee. If, meanwhile, members who have incomplete sets of these books, or for any other reason desire to secure some of them, they are asked to communicate immediately with the Secretary, as this is in unusual opportunity to secure books at a very low price. American Gas Light Journal, viols. 31 to 39. American Institute of Electrical Engineers, Transactions, vols. 5 to 26. American Machinist, vols. 3 to 20, 22 to 29. American Society of Civil Engineers, Transactions, vols. 2 to 10, 21 to 24, 26 to 33, 39 to 49, 52, 55, 58, 74. Index, viols. 1 to 21. American Society of Mechanical Engineers, Transactions, vols. 1 to 28. Index, vols. 1 to 20, vols. 1 to 25.

Jan 1, 1916

By Robert S. Nichols

Fording Coal Limited's mine in the Rocky Mountains near Elkford, B.C. has produced 21.8 million clean tonnes of metallurgical coal from 1971 to 1980, inclusive. This production has come from several pit areas and required the removal of 149.1 million bank cubic meters of waste rock and overburden by truck-shovel and dragline operations. Waste dumps from 30m to 200m in height have been successfully constructed on natural slopes, generally between 10° and 26°. Design considerations for the dumps include foundation and soil conditions, natural slope angles and containment of weak overburden or rehandle materials. Dump control is maintained by monitoring the crest and the face of an active dump area. Crest movement is measured by extensometers locally termed "Spoil Monitors". When crest movement rates progressively increase above normal, dumping operations are temporarily relocated. Some unstable conditions and mass failures have occurred as the result of natural foundation slopes being in excess of 26°, failure of weak water saturated foundation soils or weak material being placed on the dump.

Jan 1, 1983

By AIME AIME

T HE Executive Board of the American Engineering Council held its fourth meeting at St. Louis on the first anniversary of the organizing conference which met in Washington on June 3,1920. Representatives of a number of the leading engineering organizations in the vicinity of St. Louis were present by invitation. The members of the Executive Board were guests of the Associated Engineering Societies of St. Louis. They were given a delightful ride about the city and were entertained at the Glen Echo Country Club at dinner. The special committee that had been appointed to draft resolutions to Mr. Hoover submitted the following, which were adopted : WHEREAS, our President, Herbert Hoover, has been appointed Secretary of Commerce in the Cabinet of the President of the United States, and WHEREAS, in consequence of his acceptance of this high public office, he has deemed it necessary to tender his resignation as President of The Federated American Engineering Societies.

Jan 1, 1921

By AIME AIME

AN unusual interest in the question of orienting the young college man in the mineral industry was shown in a well-attended session* of the Engineering Education Committee on Monday afternoon. About seventy-five employers and educators of mining engineers were present and took part in the discussions.

Jan 1, 1929

By H. A. Guess

AT the outset, said Mr. Guess, I may say that although I believe the present engineering courses in the various colleges and universities could be arranged to give the student within the same time limit a broader general education of un- doubted value, still I do not agree with the view held by many that engineers in comparison with those of other occupations-let us say doctors, lawyers, bankers, and so-called business men-seldom arrive at high executive positions. After all, we must remember that engineers are not very numerous as compared with the occupations just mentioned and therefore a lesser number reaching high executive positions stated numerically might be a larger number stated as a percentage. We all know there must be throughout the United States say three doctors to one engineer, but I don't think that even numerically there are as many doctors in high executive positions as engineers, and it is a fortunate thing for the country that doctors as a class are so busily engaged in alleviating sickness and suffering and in the advancement of medical science that they do not aim particularly for high executive positions.

Jan 1, 1926

By A. Lee Barrett

AN accelerated trend toward mechanical mining was noted in 1940, calling for improvements in and better performance of transportation, hoisting, and ventilating equipment. One of the most interesting experi¬ments in transportation is the track shuttle-car operation first put into use by the Princeton Mining Co. in Indiana and later at the Montour 4 mine of the Pittsburgh Coal Co. This system is based on the use of 10-ton drop-bottom mine cars operating on track and han¬dled by an ordinary gathering loco¬motive. These mine cars are loaded and taken in trips of two to a central dumping station which serves four or less loading machines. The dumping station consists of two standard chain-and-flight room conveyors, approximately 50 ft. long placed side by side approximately 4 ft. below the track from which the drop-bottom cars are dumped. These conveyors are operated at low speed and discharge into two similar elevating conveyors which operate at a higher speed and convey the coal to a trip of standard mine cars. A dumping station is usually located so that approximately 500,000 tons of coal may be handled through it before a move is required. This plan appears to have considerable possibilities for the mine equipped with small mine cars and standard locomotives since the advantages of large mine cars can be secured at a fraction of the cost required to install such cars throughout the mine. It appears logical that the future will see a much wider use of this modification in transportation.

Jan 1, 1941

By W. Rostoker, A. Siede

THE venerable problem of hydrogen embrittlement of ferritic iron lacks as yet a complete explanation. Possibly part of the difficulty has been the exclusive preoccupation with the total ductility prior to fracture. In the past few years it has been noted at least twice1,2 that hydrogen charged into iron has the ability to depress the upper yield point and, at room temperature, to eliminate completely the discontinuous yield phenomenon. Cracknell and Petchl rationalize that the depression of the yield stress is an example of the behavior of inhomogeneous stresses. Their explanation requires that microcracks exist in the annealed metal, and that hydrogen collect in these cavities under high hydrostatic pressure. The hydrostatic pressure of hydrogen generates localized tensile stresses in the iron which, with external loading, reach the critical stress for yield prematurely. The local plastic zones will spread across the specimen before the Lüders bands can be generated, and the yield-point elongation phenomenon is eliminated. This viewpoint will be discussed in succeeding paragraphs. Rogers,2 on the other hand, represents the depression of the initial flow stress as a result of the interaction of hydrogen with dislocations. He submits two alternative modes of interaction. In the

Jan 1, 1959

By J. C. Bayles

Jan 1, 1886

By SAM YOUR

PROCESSING, technology and application of non- ferrous metals-copper, lead, zinc, aluminum, nickel, precious metals, foundry metallurgy, less common metals, secondary metals-are the special field of the Institute of Metals Division. New developments in this field during 1930 are more or less briefly out- lined in this review prepared by the papers and publications committee of the Institute of Metals Division as follows:

Jan 1, 1931