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By Leonard Larson

BEFORE direct or wet smelting of copper concentrate was adopted at the McGill smelter, in November 1932, actual furnace smelting tests had indicated the possibility of smelting between 400 and 500 dry tons of wet concentrate per furnace day. Under calcine smelting practice, solid charge up to 1165 tons per furnace day had been smelted. It was realized that in order to smelt wet tonnage in equivalent amount per furnace day, a higher combustion rate and higher temperatures would be neces-sary within the furnace. The reverberatory furnace considered in the following history of wet-smelting de-velopments is a unit 127 ft. long and 28 ft. 8 in. wide, inside dimensions (Fig. r). This furnace was in operation through all the years from 1934 to date. During 1933, the first complete year of direct or wet smelting, the plant was on a curtailed copper-production basis and the available concentrate tonnage to be smelted was limited. The average coal-firing rate in the reverberatory for that year was 124 tons per furnace day. This rate was lower than the average for years immediately preced-ing under calcine smelting practice. With this coal-firing rate, an average of 391 tons of new metal-bearing material (N.M.B.M.) was smelted per furnace day. The following year, 1934, the coal-firing rate was in-creased to 139 tons and the smelting rate increased to 448 tons N.M.B.M. per fur-nace day. In succeeding years production required that either more tonnage be smelted in the one furnace or an additional furnace be placed in operation. With this situation confronting the smelting depart-ment, it was determined to continue the program of increasing the coal-firing rate and also to intensify the temperature in the smelting zone of the furnace. In order to accomplish this, various improvements were made to aid combustion within the furnace. The burners were enlarged, in-creased primary air was supplied to the burners, and changes were made in the furnace to enlarge and streamline the out-let, thus increasing the furnace draft.

Jan 1, 1940

By L. D. Jaffe

From the limited experimental data in the literature, preliminary values were derived for the thermal diffusivity of titanium alloys and for the quenching severity of various mediums used in heat treating them. The thermal diffusivity, under quenching conditions, was found to be approximately 0.006 sq in. per sec. The quenching severity H for brine is approximately 8, for water 4, for oil 0.9, for air 0.08, and for argon 0.02 in. -' The quenching severity of the Jominy-Boegehold end quench water jet against titanium alloys appeared effectively infinite. Using these results, graphs were prepared showing ideal round sizes and Jominy positions having cooled conditions equivalent to those at the center and surface of titanium alloy rounds, plates, and sheets quenched in various media. THE importance of proper quenching of steel parts has long been recognized, and much quantitative work has been done on the subject. Recently, it has become evident that for titanium alloys, too, the rate of cooling from high temperature is important in obtaining high strength and hardness. Maximum hardness and strength may not be attained in the as-quenched condition but rather after a subsequent tempering or aging treatment. Nevertheless, if cooling from temperatures near the ß transus is too slow, for the hardenability of the alloy used, a soft a-ß structure will be produced which will not harden on subsequent aging.'-" The quenching of parts of practical interest can usually be approximated by simple shapes, such as cylinders (rounds) and plates (or sheets) of various thickness and combinations of these. A standard that has been used extensively for comparison purposes is the center of an ideal round: a cylinder quenched in a medium that instantly cools its surface to room temperature." For steel, considerable practical use has been made of the Jominy-Boegehold end quench hardenability specimen,".' and its value for titanium alloys is becoming evident. It therefore appeared worthwhile to attempt comparison of cooling conditions in titanium alloy rounds and plates of various sizes quenched in various media with cooling conditions in ideal round and Jominy quenches. These comparisons are based upon measurements reported in the literature. Quenching Severity of Jominy Water Jet and of Brine As one starting point, there were available the data of Phillips and Tobin8 for positions on a Jominy specimen having the same hardness as the centers of round bars of various size quenched in 5 pct NaOH brine, shown in Table I. The Jominy speci- men is a round bar, normally 1 in. diam and 4 in. long, quenched by a water jet at one end and air cooled on the other surfaces.' After quenching, hardness is measured vs distance from the quenched end on longitudinal flats ground 0.015 to 0.10 in. deep. The data of Table I were based on a subsized specimen of 3/4 in. diam. Since the positions tested are close to the jet quenched end, cooling there may be taken as due solely to the jet, and air cooling can be neglected. These positions are then equivalent to various locations near one surface of an 8 in. plate jet quenched on both sides. Assuming that the thermal diffusivity is constant and that Newton's law of cooling holds, temperature vs time curves at corresponding positions in Jominy specimen and round bar then may be calculated for various assumed quenching severities of the water jet and of the brine. Cooling curves are generally taken to be metallurgically equivalent when they show the same time to reach a temperature halfway between the initial (heat treating) temperature and the final (quenching medium) temperature.5 On this basis, using Russell's tables,9 upplemented by heat flow tables derived in similar fashion by the author for positions near the surface of severely quenched plates, it was found that the experimentally observed equivalence, Table I, was best matched if the quenching severity H of the Jominy water jet was taken as infinite (H = co). This means that the jet quenched surface should be considered as instantly cooled to the temperature of the water

Jan 1, 1956

By P. Somasundaran, I. J. Lin

There are several methods described in the literature for the determination of the order and the rate constant for the flotation of minerals. These often involve some type of computational or graphical procedures. A relatively simpler method developed on the basis of a technique used by Chang" in chemical kinetics is described in this paper. Chang's technique, like most others in chemical kinetics," is based on the law of mass action which states that the rate of a chemical reaction is proportional to the active masses of the reacting substances at any given time. Application of this law to the flotation of minerals would involve the adaptation of the terms "flotation" for "chemical reaction" and "floatable amount of the minerals" for "the active masses of the chemical reactants." There are indeed a large number of physical processes controlling the actual flotation rate. The most inefficient one of these could be considered equivalent to the slowest reaction in a series of chemical reactions. If variables such as aeration rate and agitation are kept at constant levels, the rate of flotation under free flotation conditions (i.e., conditions under which the suspension is dilute) will be given by the following equation: where C is the concentration of the floatable minerals in the pulp at any given time t, K is the rate constant, and n is the order of the reaction. If we represent the floated fraction of the floatable mineral at time t as m (0 m - 1) and C at t = 0 as Ca, integration of Eq. 1 yields

Jan 1, 1974

By Walter Renton Ingalls

IN SEVERAL papers and addresses during the past two years, I have dwelled upon some of the economic consequences of the war. The fundamental thought that I have sought to convey is that the world became immensely poorer by the war, not only in material wealth and population, but also in the psychology and morale of the people. I do not see how there can be any intelligent dissent from that statement. All the ideas of post-war prosperity were manifestly fallacious, manifestly fallacious from the outset. If there had been any truth in them it would have followed logically that a great war, with all its destruction of wealth, health and life would be a good thing. Therefore, let us have a great war every ten years or so. Such an idea would be both monstrous and absurd. Assuming then the acceptance of my premise, I have tried to show that the losses by the war could be made good in a short time, i.e., in a relatively short time, only by doing things a great deal better than formerly, and that the accomplishment of such a result called for greater transparency in industry, for industrial cooperation, for thinking in terms of industries as a whole, and for the greater exercise of engineering functions. All of this introduced, of course, the position and psychology of labor. I say frankly that I do not look for labor to contribute any constructive thought to the upbuilding. I neither expect it nor hope for it. This is a pity, for it could do so much for its own economic advancement if it would. However, it never has done so, but rather has benefited only from the exercise of the talents of the few, and the main hope now is to bring it into a passive state, dispelling the resistive fallacies that developed during the war. Let us briefly examine the nature of these.

Jan 1, 1921

[Officers and Committees of the Society of Petroleum Engineers 1 Officers and Staff of the AIME 2 . Officers of AIME Sections Predominantly Petroleum in Membership 3 AIME Local Sections and SPE Regional Organization Maps 5 Alphabetical List of Members 7 Geographical List of Members 102 Advertisers' Index 133]

Jan 1, 1961

[NOTE.-The names of authors of papers are printed in small capitals, and the titles of papers, in italics. Casual notices, giving but little information, are indicated by bracketed page numbers. Large Roman numerals are volume numbers; small Roman numerals after volume numbers following titles indicate the page on which the presentation of the paper is mentioned; Arabic figures refer to the text of the printed papers.] A Use Classification of Coal, (ASHLEY) LXII [xiv]; LXIII, 782; Discussion: (HALL), 794; (ZERN) , 795; (ASHLEY), 795 Absorbent material, liquid-oxygen explosives, LXXI, 1251. Absorbents for liquid-oxygen explosives, LXIX, 292, 299. Absorption : cupellation : gold, special cupels, LIX, 194. primary and secondary, LIX, 213. ratio of silver to gold, LIX, 212. silver, specla1 cupels, LIX, 195. Absorption method, gasoline from natural gas, LIX, 584, 585. Absorptzon of Sulfur from Producer Gas zn Open-hearth Furnaces (NEAD), LXX, 176; Discussion: ( WATERHOUSE), 184 ; (REYNDERS) , 184; (KINNEY), 184 Accelerated wearing tests, bearing metals, LXIX, 973. Accident prevention, results, Utah, LXVIII, 360 Accident Prevention, 1919 (SINN), LXIII, [xiii] Accidents: causes in coal mines, LXXI, 1229. classification, Anaconda Copper Mining Co., LXVIII, 9. coal mining: comparison with metal mining, LXVIII, 360. pillar mining, LXVIII, 323. relation to method, LXVIII, 323 shafts, LXVIII, 207, 209 Utah, LXVIII, 363 - concentrating mills, Utah, LXVIII, 362 liquid-oxygen explosives, LXIX, 330, 339 losses through, LVIII, 65 metal mining, LXVIII, 361, 363. mine: causes, LIX, 652. curve of decrease, LIX, 655 days of greatest frequency, LIX, 657 human element as cause, LIX, 652, 653. intemperance as cause, LIX, 658 labor relation, LIX, 652 prevention, LIX, 653. record, New Jersey Zinc Co., Franklin mine, LIX, 655 time of greatest frequency, LIX, 657, 658 Utah, LXVIII, 360 prevention, LVIII, 65 report blanks, Anaconda Copper Mining Co, LXVIII, 13, 15. statistical base, Anaconda Copper Mining Co, LXVIII, 9 time lost, LVIII, 70 transportation, Clifton-Morenci district, LXX, 851.

Jan 1, 1926

Homestake's Bulldog Mountain Operation near Creede, Colorado, in the San Juan Mountains at an elevation of nearly 2,750 m (9,000 ft), is subjected to short summers and long cold winters. Creede’s history dates back to 1889 when silver ore was discovered; and by 1892 production of over a million dollars per month was being shipped from mines located along the Amethyst Fault. The Bulldog Mountain Fault remained relatively untouched by the early prospectors. The United States Geological Survey recognized the potential of this fault in 1960, which led to the staking of many claims over the structure. Homestake leased properties in 1963 and in mid- 1964 a tunnel was started at the 2,956 m (9,700 ft) level with encouraging mineralization being encountered. In 1968 a decision was reached to build a flotation mill of 318 mtpd (350 stpd) capacity. The erection of the mill was completed in early 1969, six years after the first exploration was begun. Since initial start-up, extensive drifting has been done on several separate levels. Two underground hoist installations serve the various levels and many thousand feet of vertical mining operations. Due to the unconsolidated nature of the vein, a new unique underhand cut-and- fill mining method was developed. This procedure is the reverse of the normal cut-and-fill and proceeds from the top down under cemented sand fill, which, while expensive, has greatly reduced s toping hazards. Prior to 1977, a considerable quantity of silver was lost in the slime fraction of the ores processed because of oxidation and other inherent characteristics of individual minerals. Due to Homestakefs favorable experience in treating the slime fraction of the Lead, South Dakota gold ores, experiments with leach methods to recover silver from the slimes by Carbon -In -Pulp offered' the potential for additional silver recovery. Work was begun on the Carbon-In-Pulp plant in April 1976 and completed in December of that year at a cost slightly exceeding $2 million. The C. I. P. plant was designed for 136 mtpd (150 stpd) of current plant slimes plus 227 mtpd (250 stpd) of slimes dredged from the old tailings during the summer season. The sand fraction of the flotation

Jan 1, 1981

By Elmer Weber, W. M. Baldwin

Solid lead obeys a single parabolic weight increase vs. time law. In contrast, liquid lead undergoes three successive parabolic weight increases vs. time laws, the first of which has a low constant relative to the latter two. The conversion times for the change from one parabola to the next decrease with increasing temperature. IN recent reports on the subject,1,2 it was noted that zirconium and titanium scale in air by a complex mechanism. The scale first forming on the metal is protective to the extent that it gives a low constant, K, for Tammann's, and Pilling and Bedworth's parabolic equation: w² = Kt [1] relating weight increase, w, due to chemical reaction of the metal with the air, and time, t. After hundreds of hours of apparent stability in some cases the first scale yields to another that offers little protection to the metal. This transition from one scale to another, from a slow parabolic oxidation reaction to a fast one, was not due to impurities in the atmosphere or incidental effects (changing environment, etc.) but was a specific behavior of the metal itself, the transition occurring at definite times (dependent on temperature) and showing other reproducible traits. In view of this behavior how can long-time service behavior be predicted from short-time laboratory tests, not only in the case of these metals, but in any case? Certainly a systematic study of the type of scaling behavior described above—wherever it is found—would help to answer this question. The present paper is a report on the behavior as it is found in lead—the only metal to the authors' knowledge for which the behavior has been described at all, if inadequately, for our present purpose.* At least four oxides of lead are known, of which one occurs in two allotropic forms. They are ß (red) tetragonal PbO stable up to 486°C;8 a (yellow) orthorhombic PbO stable from 486°C up to its dissociation temperature in air at about 2300°C;9 minium or Pb3O4 which from the dissociation pressure data given in Fig. 1 decomposes to PbO at 540°C in air; lead sesquioxide or Pb2O3,; and lead dioxide or PbO2 which, according to Fig. 1, decomposes in air at 400°C to minium. In view of the high dissociation temperature of PbO, lead will scale up to at least its boiling point. Further, it is known that oxygen is almost insoluble in liquid lead.'V his implies a fair probability that an oxide scale would not dissolve in the molten metal and would afford the same protection to lead in the liquid state as in the solid. All of the oxides of lead for which specific gravity data are available are more voluminous than an equivalent weight of metal or a lower oxide from which they might form, hence the scales will be in compression. Lead oxides are known to be ductile, so it would be anticipated that they would form coherent nonporous scales. It is not surprising to learn, then, that both solid and liquid lead scale according to the Tammann, and Pilling and Bed-worth law.14,15 (Gruhl states that at 600°C and above lead oxidizes linearly with time because of "spitting" of the scale.) The parabolic constants K reported by various investigators3,14-16 are badly scattered, however, as shown in Fig. 2. The oxides formed on solid lead were described as being reddish-brown but were not chemically identified by Pilling and Bedworth.15 Gruhl's descripdin³ of the appearance of the scales On his liquid samples indicates that a (yellow orthorhombic) PbO is formed initially on the specimens but gives Way eventually—at least at temperatures below 486 °C— to .ß (red tetraunal) PbO, and that below 540°C minium—Pb3O4 :is firmed at an even later time as an overlay on either the red or yellow PbO. Fig. 3 is a graphical interpretation of Gruhl's description. Gruhl does not indicate any change in the parabolic scaling rate as yellow PbO converts to red. He does indicate that minium reduces the scaling rate, al-

Jan 1, 1953

By AIME AIME

MINING geology was granted two sessions, Wednesday morning and afternoon, Feb. 17. The morning session, at which H. Foster Bain presided. first considered Paul M. Tyler's paper, "Economic Notes on Steel-making Alloys." The elements used in these important alloys are chromium, manganese, molybdenum, nickel, phosphorus, silicon, titanium, tungsten and vanadium. Edward Sarnpson and C. K. Leith asked whether chromite concentrates could be used, Mr. Tyler replying that they could if not too high in iron. G. W. Pawel said that they were used at Niagara Falls, nlixecl with coarse ore. In reply to a question asked by A. O. Hayes, Mr. Tyler said that molybdenum had not affected the price of tungsten. After this discussion, E. S. Moore's paper on nickel was considered. H. Foster Bain thought that nickel is well controlled and in good hands, technically and politically. The popular stainless steel in America is the 18:8 Cr-Ni metal. In Germany a Cr-Mn steel has possibilities. It is easy to make, cheaper. has better workability, will stand 85 per cent reduction between heats.

Jan 1, 1932

By Donald L. Katz

Charts for predicting the pressure to which natural gases may be expanded without hydrate formation have been prepared for gases of even gravity. Pressure-temperature curves for hydrate formation were established for gases having gravities from 0.6 to 1.0. These curves and the thermal behavior of the gases during free and adiabatic expansion were used to prepare the charts for estimating the permissible expansion of natural gases without hydrate formation. The problem was solved by L. F, Albright, W. T. Boyd, J. J. McKetta, G. Martin, P. Poettman. and A. P. Snyder.-, who are first-year graduate students in the department of Chemical and Metallurgical Engineering at the University of Michigan. This paper is essentially a summary of their results. Prediction of Conditions for Hydrate Formation in Natural Gases Each natural gas under a given pressure will form solid hydrates at a corresponding temperature provided sufficient water is present.1-5 The temperature of natural gases below about 5000 lb. per sq. in. decreases when the gases are expanded freely.6,7 This decrease in temperature may cause the expanding gas to enter the region of temperature and pressure at which hydrates will form' The final pressure to which a natural gas may 'be expanded without hydrate formation depends upon the initial temperature and pressure and the gas composition. This paper presents charts that give the final pressures to which gases of gravity 0.6 to 1.0 at given initial temperatures and pressures may be expanded without formation of hydrate. Hydrate-forming Temperatures and Pressures as a Function OF Gas -Gravity Experimental data of pressure versus temperature at which solid hydrate will form, provided sufficient water is present, are available for a series of gases.2,3 A method of predicting the pressure-temperature curve for a given gas composition has been reported.' The solution to this problem requires that these curves relating pressure to temperature be established for gases of given gravities.

Jan 1, 1945

By Canada Ernst & Whinney

INTRODUCTION The principal objective of this chapter is to provide guidance in understanding and making effective use of published financial statements of mining companies. Although financial statements only represent a gathering together of information relevant to an enterprise's financial position and results of operations, they increasingly reflect the complexities of the modern day business environment. In the mining industry, a wide variety of accounting practices have evolved to deal with the unique aspects of the business in the absence of authoritative accounting pronouncements from standard-setting bodies. Given such complexities and divergent practices, financial statements of mining companies are not easily understood and cannot be used effectively as a tool in decision-making without a basic knowledge of fundamental accounting concepts, generally accepted accounting principles and their application in the mining industry. As such, this chapter is not restricted to a discussion of the accounting for the unique aspects of the mining industry. These aspects are dealt with at length but the text also includes a discussion of general accounting concepts and practices which have wide application in the mining industry. Frequent references are made in the text to international practices and to specific rules and requirements of individual countries. In this respect, the scope is restricted to four major mining environments, Canada, the UK, the US and Australia, all of which have made significant contributions to the development of generally accepted accounting principles. Acknowledgements This chapter was prepared under the direction of Ian Murray of Ernst & Whinney in Toronto, Canada. Contributions were received from Graham Butt, Mark O'Sullivan and Dominic Robinson, all from Ernst & Whinney in Toronto and Bill Duvall and Tom Schoenbaechler from Ernst & Whinney in Louisville, Kentucky, US. The authors would also like to acknowledge the assistance received from David Ferguson, Don MacLean, David Taylor and Susan Zoutman from Ernst & Whinney, Toronto, from the UK and Australian practices of Ernst & Whinney and from Ernst & Whinney International. FINANCIAL STATEMENTS - ELEMENTS AND CONCEPTS Financial statements were originally a stewardship report to owners to satisfy them that management had given a proper account of the resources with which it had been entrusted. Today, the number of users of financial statements has expanded to include the following groups: - shareholders, present and prospective; - lenders, present and prospective; - financial analysts; - regulatory authorities; - taxing authorities; - labour unions and employees; and - creditors and customers. The expectations of these user groups differ. For example, investors and lenders require information that will indicate the adequacy of their security and the profitability of the enterprise; taxing authorities will be concerned with the concept of income; labour unions and employees will focus on the profitability of the enterprise. Ground Rules for Preparing Financial Statements Responsibility for Financial Statements Financial statements are the representations of management. This may strike the reader as a rather obvious statement. It is important to remember, however, the role of judgment in accounting. Notwithstanding the promulgation of accounting standards in the developed countries, considerable flexibility remains in the selection of accounting practices and methods and in their presentation. Arguably, there is more flexibility in the mining industry as few countries have developed standards to deal with its unique aspects. Accordingly, financial statements are as much a product of management's perspective and philosophy as they are a compliance document.

Jan 1, 1985

By W. M. Weigel

Economic deposits of barite occur in Missouri in two main districts. The most important, the Southeastern or Washington County district, is in the southeastern part of the state, mostly in Washington County with a small extension into the northeastern part of St. Francois County. Roughly, it embraces nine townships or about 200,000 acres and accounts for from 80 to 90 per cent. of the state production. The Central district, is in the central part of the state, includes most of Morgan and Miller counties, and parts of Camden; Benton, Moniteau and Cole counties. The area embraced is much larger than the Washington County district, but the deposits are more infrequent. The location and general area covered by the two districts is shown in Fig. 1. There is another small area in southern Franklin County but so far its production has been of small consequence. It might be considered as a northward extension of the Washington County field. An, area in the central part of Hickory County has also produced a small amount. The outline of the districts as shown indicates the general area in which deposits have been found. The total area covered by deposits of barite is only a small part of this, as, in the Central district especially, there may be miles of supposedly barren areas between ore-bearing areas of an acre or two in extent. The date when barite was first mined in Missouri cannot be definit stated, but the industry probably dates back to about 1860. The occurrence of barite was known long before this, as it was encountered in the lead mines in Washington County and mentioned by several earlier writers." Missouri is reported as producing 8000 tons in 1882 so it is evident the industry was well under way in the seventies in order to have arrived at this substantial production. By 1893 Missouri production had increased so that it ranked with that of Virginia, then the largest producer it increased until in 1914 Missouri accounted for about 65 per cent. of the total United States output.

Jan 1, 1929

CONTENTS PAGE Need for Research in Foundry Pig Iron. By Richard Moldenke. (With Discussion) 1 Carbon Characteristics of Copper-bearing Pig Iron. By W. B. Coleman. (With Discussion) 12 A Pig Iron, Low in Total Carbon, is in Demand for Use in Various Industries. By Enrique Touceda. (With Discussion) 24 Carbon in Pig Iron. By Ralph H. Sweetser. (With Discussion) 28 Second Session (Discussion) 37 Need for Research in Foundry Pig Iron BY RICHARD MOLDENKE,* WATCHUNG, N. J. So FAR as the quality of the product is concerned, the history of the production of pig iron for foundry purposes is one of constant retrogression. The steps in this deterioration began with cold-blast charcoal pig iron, then anthracite iron, coke iron; then gradually warm to hot-blast coke iron, with the charcoal furnaces also heating their blast to get greater tonnages, and finally the present-day hot-blast coke irons with scrap additions to the ordinary burden that, according to one European report, have gone as high as 65 per cent. Parallel with this quality retrogression is the enormous increase in furnace tonnages from about 15 to over 1000 tons per day in exceptional instances of modern practice. The key to this situation is economic pressure. The effect is a growing differentiation between furnace production for gray iron and malleable foundries and, for the

Jan 1, 1927

By R. P. Marshall

This note describes positive evidence that hydrogen in titanium alloys diffuses under the influence of a thermal gradient. The experiments confirmed the expected similarity of this system to the H-Zr system and produced qualitative information on the magnitude of the heat of transport for hydrogen in titanium alloys. This effect has practical importance in applications where titanium alloys operate in a thermal gradient under conditions such that hydrogen embrittlement may develop within the expected lifetime of the structure, for example in supersonic aircraft service. The theories of thermal-gradient diffusion may be found in recent reviews and experimentation in this field by Shewmon,1 Sawatzky,2 Markowitz,3 and Darken and Oriani.4 The basis for Soret thermal diffusion is the "heat of transport", denoted by Q*. This is an energy term for the amount of heat (energy) transferred by atomic diffusion, and can be either positive or negative signifying a driving force for atomic diffusion to the cooler or hotter region, respectively. Experimentally, Q* is determined by plotting the natural logarithm of the point-to-point concentrations after exposure to a thermal gradient vs the respective point-to-point temperatures in units of the inverse absolute temperature scale. The slope of the straight line is Q*/R, R being the gas constant. For the titanium experiments, specimens (3 by 1 by 1/16 in.) of a) commercially pure titanium, b) the 8 Al-1 Mo-1 V titanium alloy, and c) the 6 A1-4 V titanium alloy were exposed to thermal gradients of 6° to 115°C per in. for 18 days at 250° to 550°C. The temperature gradient was in the direction of the 3-in. dimension. The hydrogen concentrations existing after exposure were determined on sections of the specimens by vacuum extraction. Three sections of unexposed sheet of each alloy were analyzed as standards to allow a check for hydrogen

Jan 1, 1965

MEMBERS-QUALIFICATIONS AND ELECTION SEC. 1. The membership of the Institute shall comprise seven classes, namely: 1. Members; 2. Honorary Members; 3. Senior Members; 4. Associates; 5. Junior Members; 6. Rocky Mountain Members; 7. Junior Foreign Affiliates. All shall be equally entitled to the privileges of membership, excepting that no member of any class whose residence shall be outside of the United States of America, except those residing in Mexico and Canada, shall he entitled to vote. SEC. 2. Members: A person to be eligible for election or transfer into the class of Member must be at least 27 years of age and must have had at least six years' employment in the practice of engineering, mining, geology, metallurgy, or chemistry, during at least three years of which be must have held positions of responsibility in one or more of these fields. This shall not apply to Rocky Mountain members. SEC. 3. Honorary Members: Each candidate for Honorary Membership must be recommended by at least ten Members and must be elected by ballot at a meeting of the Board of Directors by the unanimous vote of the Directors present; provided, however, that the number of Honorary Members shall at no time exceed twenty. Such election shall automatically act as a transfer of such member from any other class of membership to which be may belong.

Jan 1, 1938

By George Anagnostache

AMONG the petroleum-producing countries of the world, Roumania occupies the fifth place; in Europe, it occupies second place, coming after Russia. The extraction and the use of petroleum in Roumania, may be trace( as far back as 1856, but the production on an industrial scale started in 1896, when the "Steaua Romana," was formed. From that time until the beginning of the war, the petroleum industry had a rapid growth the number of the producing companies increased to 37, and production FIG. 1.-ROUMANIAN OIL AND GAS FIELDS. increased from 81,571 tons, in 1896, to 1,898,545 tons, in 1912, when the greatest production was reached. In 1916, when the Germans invaded Roumania, the oilfields, at the order of the Allies and under British supervision, were destroyed, to pre vent their exploitation by the Central Powers; the wells were blown in the refineries and the storage tanks burnt, and pipelines put out of order This voluntary destruction, which weakened the resistance of the Central Powers, set back the petroleum industry at least one decade. Reconstruction after the war was slow, because of bad transportation conditions the scarcity of drilling and refining material, the insufficiency of. electric power, and the continuous depreciation of the Roumanian money, which made difficult the buying of the necessary materials for reconstruction.

Jan 3, 1925

By Simon D. Strauss

What are future prospects for U.S. mining? In many quarters the assumption is made that this country has passed its zenith as a mineral producer -- that it is in a period of decline and that it is becoming a have-not nation like Japan and much of Western Europe. These industrial rivals of ours must depend almost entirely on others for their mineral supplies. In trying to answer this question one must of course distinguish between resources and productive capacity. In today's volatile and competitive markets, the definition of what are reserves and what are merely identified resources becomes ever more difficult. Many large deposits have been found that are unlikely to be viable in the marketplace under normal conditions but that can be of significance to the nation's military and industrial security in times of emergency. I should like to draw on personal experience from World War I1 for illustration. 4fter Pearl Harbor great concern developed over the availability of a long 1ist of strategic materials for which this country was largely dependent on imports. Included were a number of minerals of which domestic deposits had been identified. Among these were chromite, manganese ore, mercury, mica and tungsten.

Jan 1, 1982

By J. E. Burke, C. W. Mason

IN attempting to study precipitation from a tetragonal lattice using solid solutions of bismuth in tin, it was found that although a Widnmanstatten pattern is observed 1 only a qualitative analysis of the orientation relationships is possible, because of the unusual structural changes that accompany the precipitation process MICROSCOPICAL STUDIES Alloys were made from Chempur tin (Standard samples 42b and 42c, National Bureau of Standards), and bismuth (Kahlbaum C P ) by melting neighed quantities together under palm oil, stirring well, and casting in a heated graphite mold The polishing and etching techniques employed largely govern the visibility of the structural changes The preliminary surfacing operations were similar to those recommended by Villela and Bergekoff,5 through BehrManning 3/o abrasive papers, lubricated by a solution of paraffin in kerosene A rough metallographic polish was next given, using a thin cotton cloth charged with relevigated alumina (maximum particle size of about 4µ) and soap solution, repeated etching and polishing served to remove disturbed metal For high-power examination better preparation was necessary It was found that on such soft metals the threads of the fabric, rather than the abrasive, cause most of the scratching Cotton outing flannel, which had been brushed so that the nap lay down, was fairly satisfactory, but a Heavy grade of silk velvet (not the noncrushable kind) was found to be better, especially after some use A better procedure was as follows The metal lap was warmed slightly, and a 4-in circle of woolen broadcloth was cemented to its center by a thin film of melted paraffin The broadcloth was then moistened with water, and a 30 to 40 per cent solution of sodium hydroxide heated to about 50°C was poured over it, allowed to stand for 1 to 2 min and then washed off It was neither necessary nor desirable to remove all the sodium hydroxide from the cloth, since its etching action aided in the removal of the flowed layer from the sample The cloth was then charged with a paste of the relevigated alumina in water Since this lap did not remove deep scratches, it was necessary previously to polish the specimen on some material such as the silk velvet The sodium hydroxide softens and partly gelatinizes the woolen lap covering, permitting a scratch-free polish, but its action continues, and the cloth deteriorates after about 24 hr This is not serious, because a new lap can be prepared in about 5 min, and only small pieces of cloth are used Etching with a strongly acid solution of ferric chloride was found satisfactory for removing the flowed layer For the final etching, the most satisfactory reagent was that of Taffs,7 the formula for which is FeC13 6H20, 2 grams, HC1, 5 c c , H2O, 30 c c , C2H5OH (95 per cent), 60 c c This etchant reveals differences in com-

Jan 1, 1941

THE activity of the principal oil fields of Rumania followed the same course as in 1939. It was marked by (1) collaboration between the various companies, particularly in exploiting oil at great depths with a view to rationalizing the exploitation and decreasing the difficulties inherent in very deep drilling; and (2) economy in the exploitation of the older pools in reducing to a minimum the cost of the extraction and working over of wells by the concentration of productive wells in groups. The pooling arrangement continued at Tintea as a measure of conservation, and exploitation of the unitized region went forward on the basis of the norms established in 1939. The same methods were applied in the fields of Liesti, Ceptura and Boldesti. The petroleum industry had some difficulty in providing the necessary material and the hands for work. Importation of material and machines from the United States was virtually stopped. Substitutes were provided from Germany but particularly useful were certain dispositions made by the local metallurgical industry. Despite the higher cost of the production of local material and machines, they were superior to the German product, the difference in quality justifying the higher price charged as the materials were found to be particularly adapted for the purposes of the petroleum industry. The cost of production was still further raised by the work that was imposed for national defense. The rise in costs per meter drilled was 50 per cent over those of 1939. According to bimonthly tables furnished by the Moniteur du Petrole Roumain, the deepest well completed in 1940 was an exploratory well, No. 201 of the Concordia company, drilled at Tintea and suspended at 3338 meters. This depth was reached toward the close of 1939 and the well was not deepened in 1940 became of large deviation from the vertical. The record for productive wells had been held by No. 429 at Tintea, drilled by Unirea to a depth of 3200 m., and in 1938 well No. 317 Cocorasti-Mislea, of the Colombia company, but these records were passed in 1940 by well No. 613 Liliesti of the Con-cordia company, which reached a depth of 3294 m. and had an initial production of 10 tons per day. In 1940, the same number of wells, II, had been drilled to a depth of over 3000 m. as in 1939. Five of these wells are at Tintea and six at Liliesti. Table I lists these very deep holes in the order of their depth. Table i.—Deep Wells Drilled in Rumania in 1940 Initial No. Produc- of Company Field Meters tion, Well Meters Tons per Day 405 Colombia......... Liliesti 3,001 10 629 Unireu............ Tintea 3,005 73 426 Unirea............ Tintea 3,050 48 410 Colombia. ........ Liljesti 3,055 30 627 Concordja (Unirea). Liliesti 3,072 75 430 627ConcordjaConcordia (Unirea). (Unjrea 3,II9 30 618 Colombia......... Liliesti 3,168 70 24 Steaua Romana. . . Tintea 3,184 18 412 24Unirea............ Tintea 3,211 23 613 Concordia......... Liliesti 3,294 10 Production in Rumania in 1940 reached 5,813,000 tons, in contrast to 6,~40,0oo tons in 1939, a decline of 427,000 tons, or 6.8 per cent. Drilling reached 241,500 m., in

Jan 1, 1941

THE activity of the principal oil fields of Rumania followed the same course as in 1939. It was marked by (1) collaboration between the various companies, particularly in exploiting oil at great depths with a view to rationalizing the exploitation and decreasing the difficulties inherent in very deep drilling; and (2) economy in the exploitation of the older pools in reducing to a minimum the cost of the extraction and working over of wells by the concentration of productive wells in groups. The pooling arrangement continued at Tintea as a measure of conservation, and exploitation of the unitized region went forward on the basis of the norms established in 1939. The same methods were applied in the fields of Liesti, Ceptura and Boldesti. The petroleum industry had some difficulty in providing the necessary material and the hands for work. Importation of material and machines from the United States was virtually stopped. Substitutes were provided from Germany but particularly useful were certain dispositions made by the local metallurgical industry. Despite the higher cost of the production of local material and machines, they were superior to the German product, the difference in quality justifying the higher price charged as the materials were found to be particularly adapted for the purposes of the petroleum industry. The cost of production was still further raised by the work that was imposed for national defense. The rise in costs per meter drilled was 50 per cent over those of 1939. According to bimonthly tables furnished by the Moniteur du Petrole Roumain, the deepest well completed in 1940 was an exploratory well, No. 201 of the Concordia company, drilled at Tintea and suspended at 3338 meters. This depth was reached toward the close of 1939 and the well was not deepened in 1940 became of large deviation from the vertical. The record for productive wells had been held by No. 429 at Tintea, drilled by Unirea to a depth of 3200 m., and in 1938 well No. 317 Cocorasti-Mislea, of the Colombia company, but these records were passed in 1940 by well No. 613 Liliesti of the Con-cordia company, which reached a depth of 3294 m. and had an initial production of 10 tons per day. In 1940, the same number of wells, II, had been drilled to a depth of over 3000 m. as in 1939. Five of these wells are at Tintea and six at Liliesti. Table I lists these very deep holes in the order of their depth. Table i.—Deep Wells Drilled in Rumania in 1940 Initial No. Produc- of Company Field Meters tion, Well Meters Tons per Day 405 Colombia......... Liliesti 3,001 10 629 Unireu............ Tintea 3,005 73 426 Unirea............ Tintea 3,050 48 410 Colombia. ........ Liljesti 3,055 30 627 Concordja (Unirea). Liliesti 3,072 75 430 627ConcordjaConcordia (Unirea). (Unjrea 3,II9 30 618 Colombia......... Liliesti 3,168 70 24 Steaua Romana. . . Tintea 3,184 18 412 24Unirea............ Tintea 3,211 23 613 Concordia......... Liliesti 3,294 10 Production in Rumania in 1940 reached 5,813,000 tons, in contrast to 6,~40,0oo tons in 1939, a decline of 427,000 tons, or 6.8 per cent. Drilling reached 241,500 m., in

Jan 1, 1941