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By Evan Evans

IT is appropriate to evaluate 1947 in review as a year of a peacetime record production of about 676,000,000 tons of coal (anthracite and bituminous), closely approaching the extraordinary wartime output in 1944. Considering the general price-wage inflation, it is in point to note that the coal industry sustained the highest wages paid to workers in any major industry, but that coal prices at wholesale levels have risen much less percentage wise than the average for all commodities. The sellers' market continues to prevail. In addition to serving our own country's enormous needs, our coal industry is exporting extraordinary tonnages overseas. This unusual export demand is likely to continue for a while. Moreover, the demand in Europe for American coal mining machinery is a real tribute to the management efficiency of our modern mechanized coal industry. Competitively, the petroleum industry is concerned over its long-term supply, and already a synthetic fuels industry is being publicly advocated. In due time coal and lignite are bound to be

Jan 1, 1948

By William P. Blake

In directing attention to the newly-opened zinc-ore region in Southwestern New Mexico, I adopt a suggestion made at the Engi neering Congress last summer in Chicago by Prof. Le Neve Foster, who commended the indication of the geographical position of a district under description by means of an outline-map. Such a map is the more important in this instance, inasmuch as the region to be described is remote and little known even in the United States. Until within a few years it has been infested by the savage Apaches, has not been often visited by mining engineers, and could not be

Jan 1, 1895

TO THE BOARD OF DIRECTORS AND MEMBERS OF THE AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS GENTLEMEN Submitted herewith are the report of the Treasurer for the year 1937 and the reports for the same year of the following standing committees: Admissions, Membership, Papers and Publications, Library, Student .Relations, Speakers for Local. Sections and Student Societies, and Mining and Metallurgy. To these reports members are referred for further details. Finances.-Income for the year was the largest since 1930, the figure being $189,394, an increase of $18,803 compared with income for 1936, exclusive of a special Rocky Mountain Fund appropriation of $2500 in that year for visits to western schools and Local Sections. Major items of increase were: $8,000 from current dues and arrears; $7,700 from advertising in MINING AND METALLURGY and the two periodical "Technologies"; and $4,800 from sales of TECHNICAL PUBLICATIONS (pamphlets) and TRANSACTIONS volumes for both current and former years. Initiation fees and clues from new members declined $2,300, principally because of the larger 'proportion of Junior Members to Members among the new enrollments. Junior Members pay no initiation fee and dues are $10 compared with $15 for Members.

Jan 1, 1938

By KENNETH W. GREENAWALT, William Greenawalt

THE patent system, through which an inventor is given exclusive right to his invention for a limited period as a reward for his industry and in reimbursement of his expenditures, originated in England in the famous "Statute of Monopolies," enacted in 1623. The first patent granted in America was to Samuel Winslow, in Massachusetts, in 1641. The basis of the patent system of the United States is a provision in the Constitution giving Congress the power to secure to inventors for a limited time the exclusive use of their discoveries. The first legislative enactment was the law of 1790, which was placed on the statute book after Washington had addressed Congress in its favor. Under this law, the Secretary of State, the Secretary of War, and the Attorney General constituted the board for the examination of patent applications and the granting of patents. The first Secretary of State, Thomas Jefferson, became the first administrator of the patent sys- tem in this country. He personally examined every application filed during his term of office.

Jan 1, 1930

By Juan Sodi, John F. Elliott

The standard free energy of ReS2 has been measured in the range of 1050° to 1250°K using H2/H2S mixtures and a slight variation of the method described by Hager and Elliott.1 The result is: The experimental method and apparatus were modified slightly for this study. Measurements on Cu2S were made to verify the application of the method to the work on ReS2. THE EXPERIMENTS AND RESULTS Briefly, the experimental method consisted of exposing a chip of copper or rhenium at a known temperature for 8 hr to a slowly flowing gas stream at the same temperature in which Ph2S and PH2 were known. The chip was withdrawn quickly from the hot furnace, and subsequently it was inspected for the presence of a sulfided surface. In the experiments described here, there was no ambiguity in any case as to the presence or the absence of the sulfide. At a given temperature, gas compositions for sulfidization were explored systematically until two compositions were found whose values of ?G°, Eqs. [I] and [2], were within approximately 100 cal of each other, one of which was sulfi-dizing and the other was not. These are termed the "straddle" compositions and it is assumed that the equilibrium composition lies between them. The chief modification to the apparatus, which is shown schematically in Fig. 1 of Ref. 1, was to support the metal specimen on a small alumina boat which could be moved along the reaction tube, 6 mm ID, by platinum wires. An appropriate seal at each end of the reaction tube permitted the sample to be moved from the cold end of the tube into the hot zone in 2 to 3 sec, and the sample could be withdrawn equally rapidly. Thus, it was possible essentially to quench the specimen from the reaction temperature with the reaction gas or helium flowing and without danger of breaking the reaction tube. The usual practice at the end of the experiment was to switch the gas system to the helium tank, flood the reaction chamber with helium, and pull the sample out of the hot zone. The purpose of the modification was to permit study of the sulfidization of copper without the complication of the back-reaction between the gas and the specimen as the latter cooled during slow withdrawal of it from the hot zone; this was a problem in the earlier work.&apos; A further improvement located the tip of the temperature-indieating thermocouple and the specimen precisely at the hottest part of the furnace. A carefully calibrated thermocouple, with its tip at the position of the specimen and with other conditions duplicating those of an actual experiment, showed that in the temperature range of 900° to 1122°C the temperature of the specimen differed from that of the tip of the indicating thermocouple by less than 0.5°C. The two positions were 0.5 cm apart. The reaction gas was prepared from ultrahigh-purity hydrogen (<l ppm O2, <0.5 ppm H2O) and CP grade hydrogen sulfide (99.5 pct H2S). High-purity helium (99.995 pct He) was used. All of these gases were purchased from the Matheson Co. All flow meters were recalibrated by the soap-bubble method with hydrogen, H2S, helium, and several gas compositions used during the study. These calibrations gave a linear relationship with a slope of 1.0 for the plot of log flow rate vs log pressure drop across the flow meter, in accordance with the Hagen-Poiseuille equation. The analysis of the gas was determined in the same manner as was reported previously. Good checks were obtained between the composition of the gas established by the flow-meter settings and by chemical analysis of the gas taken after the mixing bulb and ahead of the furnace. The pressures of H2S, H2, S2, and HS in the equilibrium gas at temperature were calculated from the following data :3 The pressures of the species S and S8 were negligible for the conditions of the experiments.3 There was no sign of vaporization of ReS2 either by weight loss or deposits in the reaction tube. Thus it is not possible to account for the apparent volatility of the compound reported by Juza and Biltz.2 The inlet gas composition and the calculated equilibrium ratio of PH2 S/PH2 for the "straddle" points of each experiment are shown in Table I. The specimens of metal for the experiment were small clippings of annealed copper (99.9+ pct) sheet 0.005 in. thick that was obtained from Baker and Adamson and of "high-purity" rhenium (99.9+ pct) sheet 0.005 in. thick that was purchased from Chase Brass and Copper Co. A specimen was removed from the apparatus; inspected for the presence of the sulfide, and then stored in a sealed vial. A fresh clipping was used in each measurement. The condition of the surface of each specimen after the experiment is noted in Table I.

Jan 1, 1969

By Harry Seltz, J. C. DeHaven

InteRmetallic compounds are formed in many binary metal systems. Some compounds are stable to their melting points, and others decompose at lower transition temperatures. Even those of the first class are dissociated in the liquid state, as indicated by the continuous form of their solubility curves at their melting points1. While the lattice structures of some of these compounds have been determined, their thermodynamic properties have not been investigated. In this paper is described the determination of the free energy and heat of formation of the compound CdSb, which is of the first class mentioned above, melting congruently at 455&apos; C. This compound shows a rhombic structure, and the lengths of the edges of the elementary cell containing four molecules are: a = 6.52, b = 8.60, c = 4.16 A.&apos; There are three possible methods of determining the free energy of formation of a compound of this type. The first method, applying the third law of thermodynamics, requires the measurement of its heat capacity preferably to liquid hydrogen temperatures, and a calorimetric determination of its heat of formation. The second method involves the study of the equilibrium of the compound in some gas reaction, such as: CdSb + CO² = CdO + CO + Sb From the known free energies of formation of CdO, CO² and CO the free energy of formation of CdSb could be calculated. The third method measures the electromotive force of a galvanic cell in which the cell reaction is the reversible formation of the compound from the elements. The first method is generally applicable, but requires elaborate experimental equipment. The second method can not be used for compounds melting at low temperatures, owing to the difficulty in establishing equilibrium. The electromotive force method, therefore, seemed to offer

Jan 1, 1935

By J. C. DeHaven, Harry Seltz

InteRmetallic compounds are formed in many binary metal systems. Some compounds are stable to their melting points, and others decompose at lower transition temperatures. Even those of the first class are dissociated in the liquid state, as indicated by the continuous form of their solubility curves at their melting points1. While the lattice structures of some of these compounds have been determined, their thermodynamic properties have not been investigated. In this paper is described the determination of the free energy and heat of formation of the compound CdSb, which is of the first class mentioned above, melting congruently at 455&apos; C. This compound shows a rhombic structure, and the lengths of the edges of the elementary cell containing four molecules are: a = 6.52, b = 8.60, c = 4.16 A.&apos; There are three possible methods of determining the free energy of formation of a compound of this type. The first method, applying the third law of thermodynamics, requires the measurement of its heat capacity preferably to liquid hydrogen temperatures, and a calorimetric determination of its heat of formation. The second method involves the study of the equilibrium of the compound in some gas reaction, such as: CdSb + CO² = CdO + CO + Sb From the known free energies of formation of CdO, CO² and CO the free energy of formation of CdSb could be calculated. The third method measures the electromotive force of a galvanic cell in which the cell reaction is the reversible formation of the compound from the elements. The first method is generally applicable, but requires elaborate experimental equipment. The second method can not be used for compounds melting at low temperatures, owing to the difficulty in establishing equilibrium. The electromotive force method, therefore, seemed to offer

Jan 1, 1935

By F. E. Rizzo, L. R. Bidwell, D. F. Frank

THE use of galvanic cells for the determination of oxygen activities has spread rapidly since the suitability of calcia-stabilized zirconia as a solid electrolyte material was first demonstrated by Kiukkola and Wagner.&apos; In many of these investigations:-7 including several at ARL, the free-energy changes for various oxidation-reduction reactions involving the oxides FexO, NiO, and Cu2O have been measured as a means of assuring that a cell apparatus is functioning properly. As a result, a large quantity of data pertinent to the calculation of the high-temperature standard free energy of formation (?GO) of these oxides has been accumulated. AGFexo has been carefully measured in many independent investigations, using a variety of techniques, and consequently is accurately known. chipmans has used this informa-

Jan 1, 1968

By Anthony Anable

THE definite trend to stricter specifications with respect to hydraulic concrete has become increasingly manifest in the last six years or so; but it remained for the vast reclamation projects of the Bureau of Recla-mation of the Department of the Interior of the last few years to focus attention on this trend, and to demonstrate how thousands of tons of concrete-making aggregates can be produced continuously and auto-matically with a control of fineness comparable with that obtained with small samples in well equipped private and governmental laboratories. Pioneer work in this direction was done, to be sure, by private com-panies, notably the Kaiser Paving Co. of San Francisco, prior to the present vast public works program. Then in 1931 came the first great, aggregates-preparation plant of the Six Companies, Inc. to supply construction materials for Boulder Dam&apos; in Nevada, and now, in 1936, the aggregates plant of the Mason-Walsh-Atkinson-Kier Co., general con-tractors on the Grand Coulee dam in Washington. At Boulder dam and to an even greater degree at Grand Coulee dam, sand production is recognized as probably the most important single element affecting the physical characteristics of the concrete. For in the construction of dams accurate grading of the fine aggregate has consider-able bearing on the attainment of a uniform and homogeneous concrete of a high degree of workability and placeability and, at the same time, combining high density and low cement content. Low cement content is of value not only from the standpoint of economy but also because the use of an unnecessarily rich concrete causes certain undesirable characteristics to develop. This paper will relate how at Grand Coulee dam methods that are more advanced than ever before are producing four sizes of gravel and a sand having a fineness modulus of 2.5-3.0. The design capacity is 1000 tons an hour. Significantly, the methods and equipment employed are broadly those that have been used for a generation in metallurgical mills for accurately sizing and grading both precious

Jan 1, 1936

By T. M. Girdler

IN THESE perilous days of world- wide uncertainty, this Institute and the profession represented by it take on new importance in the economic life of the nation. I have long been impressed by the fact that the objects of the A.I.M.E. are purely professional and scientific. The country has benefited from your honorable tradition of adherence to those objectives over a period of 68 years. The Institute&apos;s policy of refraining from controversial matters - has made possible the serious, balanced, and uncolored consideration of the particular problems that come before it.

Jan 1, 1939

By Edward W. Parker

I. INTRODUCTION. AT the Seventy-sixth meeting of the Institute, held in New York, N. Y., February, 1899, I presented a, paper on this subject entitled, Coal-Cutting Machinery,&apos; which has become somewhat out of date, in view of the decade&apos;s development in this feature of the coal-minim industry. It should be explained that the present paper is limited to the use of mining-machines in bituminous mines. Practically all of the anthracite mined is ?shot from the solid," no undercutting being done. Anthracite-mining is therefore not considered in the statistics or other references. The statistical record as compiled by the United States Geological Survey shows that in 1898, the year preceding the presentation of my former paper, there were 32,413,144 short tons of coal undercut by the use of machines. In 1907 the machine-mined coal-product amounted to 138,547,823 short tons. In sympathy with the general decrease in coal-production during 1908, the output of machine-mined coal decreased to 123,183,334 short tons, but the proportion of machine-mined coal to the total output, nevertheless, showed an increase, from 35.1 per cent in 1907 to 37 per cent in 1908. In 1898 only 19.5 per cent. of the total product was undercut by the use of machines. The number of undercutting-machines in use in the bituminous mines of the United States has increased from 2,622 in 1898 to 11,144 in 1907, and to 11,569 in 1908. The total production of bituminous coal in the United States in 1908 was almost exactly double that of 1898, while the machine- * Published by permission of the Director of the U. S. Geological Survey. 1 Trans.. xxix.. 400 to 4,59 (1899).

Sep 1, 1910

By Claude H. P. Lupis, John F. Elliott

WAGNERL described the thermodynamic behavior of a metallic solution consisting of the solute components 2, 3,... at very dilute concentrations in the solvent, 1, in terms of the excess partial molar free energy, or alternatively the logarithm of the activity coefficient. In the Taylor expansion of FiE, by neglecting the second- and higher-order differential terms, he obtained the excess partial molar free energy as a linear function of the composition:

Jan 1, 1965

BIRINGUCCIO was born in Siena in 1480, the son of Paolo and Lucrezia di Bartolommeo Biringuccio.* He was baptized on October 20 of that year with the given names Vannoccio Vincenzio Austino Luca. His father appears to have been an architect, for in 1504 he was paid 600 scudi for his work on the walls of the Communal Palace and at the same time he was superintendent of streets for the city. The course of Biringuccio&apos;s life followed closely the checkered fortunes of the Petrucci family of Siena. A warm supporter of Pandolfo Petrucci, Biringuccio did not falter in his allegiance to the family and their party during his lifetime. It was probably to the protection and patronage of this lord that he was indebted for the opportunity to travel widely through Italy and into Germany during his early years and so to lay the foundation for the extensive knowledge of the subjects he was to describe in the Pirotechnia. In 1507, as he himself indicates (p. 48), he was &apos;in Friuli and. Carnia in northern Italy after having traveled in Germany,, and he also visited the, brass, works in Milan. After returning to Siena; he was sent by Pandolfo to direct the iron mines in near-by Boccheggiano. When Pandolfo died in 1512 (in which year Biringuccio&apos;s s father also died), Biringuccio continued to support the Petrucci family in the person of Pandolfo&apos;s son, Borghese, who succeeded, to the rule. Under his patronage, Biringuccio was appointed to a post in: the Armoury of the Siena Commune in 1513. In ISIS a popular uprising forced Borghese and his followers, including Biringuccio, to flee from Siena. Biringuccio and the goldsmith Francesco Castori, head of the mint, were accused of having debased the coinage alloy with the knowledge and consent of Borghese. When he failed to appear in 1516 to answer these charges-which may well have been invented by the opposing political faction-Biringuccio was declared a rebel and was exiled as a traitor to the Republic. He then traveled about Italy, was in Rome and Naples, and visited Sicily in 1517.

Jan 1, 1942

By H. J. R. Way

THE work to be described was undertaken at various periods from 1937 to 1939 on the Busia gold field, in the eastern province of Uganda. It was decided to examine the possibility of reef prospection by the resistivity method, for it was not known how far the usually disintegrated nature of most reefs in the ubiquitous laterite near the surface would obscure indications obtained by resistivity traverses. The work at the commencement was therefore largely experimental, but the results obtained thereby were satisfactory, and a survey was started at the Government closed area at Amonikakine. With the limited time and resources at the writer&apos;s disposal, it was not possible to complete the survey to his satisfaction or to follow up exhaustively all the geophysical indications, but some of the results of the experimental work and the survey were of sufficient interest to be worth recording; in particular the relation between the width of reef, electrode separation and shape of the curve, and the interference effect of constant separation curves over zones of float are significant and useful. Three new veins were located, but only one contained sufficient gold to warrant detailed prospection. This was called the Geophysical reef, and was uncovered over a strike distance of 1140 ft., and there are indications that it extends over a distance of 1990 ft. These results and the recommendations consequent therefrom were embodied in a special report to the Uganda Geological Survey. HISTORY OF THE FIELD The Busia field is in the southeastern corner of Uganda near the Kenya-Uganda border, and is about 17 miles north of the northeastern corner of Lake Victoria. Gold was first discovered in the area in the stream beds by Davies1,2 in 1932. Subsequently numerous small alluvial claims were worked by prospectors and the area was prospected for reef by a company for periods varying from three to nine months, but was finally abandoned, as the results were considered unfavorable. Further prospecting by the Geological Survey in 1935-1936 under Davies3 and later under the writer4 uncovered three reefs with sufficient gold values to be of economic interest. These were finally taken over by a company known as Borderland Syndicate, which still owns the area, and from September 1937 to the end of 1941 about 13,000 oz. of gold was extracted from reefs of the area proved by the Geological Survey. Opencast mining operations are still proceeding (February 1943). The Amonikakine area lies to the immediate north of that of Borderland Syndicate. A certain amount of prospecting had been done when the writer started work there. As a result of his report, this area was taken over by another syndicate, but little further work was accomplished before it ceased operating because of difficulties of wartime working.

Jan 1, 1944

By W. A. STERLING

IN the opencut iron mines of the Mesabi Range in Minnesota, the trend in mining is in the development of mining equipment and mining methods which will move surface overburden and ore-bearing materials with less labor and at a cheaper cost. This is a must for most of the independent operators. Their reserves of direct-shipping ore are extremely small and their operations are being conducted in small, or intermediate pits, with a high stripping ratio in the outer fringes, or shore lines of older pits. and in ore bodies passing from direct shipping to the washing and the intermediate, or retreat ore state. The trend is toward deeper stripping, longer and steeper hauls, and the necessity of moving a total of from three to five or six tons of overburden and ore material for each ton of shipping-grade ore produced. This naturally calls for greater production, with larger shovels, or draglines. cheaper drilling and blasting costs through the drilling of larger-diameter blastholes, and cheaper haulage through the use of trucks of larger capacity and more extensive use of belt-conveyor systems. This trend is notable both in stripping and mining.

Jan 1, 1948

By Carle R. Hayward

THOUGH recent months have seen a rapid decline in lead-smelting activity and consequent uncertainty as to the future, the first half of the year showed progress in keeping with similar activity in other metals. Demand for scrap increased and various lead-bearing materials found their way to plants producing secondary lead. Some of these materials introduced complications into normal smelting procedure and were the cause of many conferences among plant officials attempting to find the most satisfactory method of treatment. If a blast furnace is to do itself justice it must be run with an open charge. Troubles inevitably result when materials are added to a charge which tighten it up and pre- vent free burning of the coke and con- sequent rapid smelting with a clean hearth This fact has long been recognized by plants producing primary lead, but only recently only it received the attention it deserves.

Jan 1, 1938

By Thomas T., Read

E DUCATION for the mineral industry was at first a single comprehensive curriculum, but it was early recognized that the main basis of mining is physics, while that of metallurgy is chemistry. The first school to offer curricula leading to degrees in mineral industry education in the United States (1853) had separate ones in mining and metallurgy. The Columbia School of Mines (the first really successful one) had only a single curriculum when it opened in 1864, but within a few years had so reorganized its work that it offered curricula in mining, metallurgy, geology, chemistry, and civil engineering. Interest in the metallurgy or geology curricula was slight at first, and for the next 30 years the great majority of Columbia students took the mining curriculum, probably partly because it contained nearly as much geology as the geology curriculum, practically all the metallurgy, and most of the chemistry, and partly because of the degree awarded for it. Other schools kept their mining curricula equally broad, and as late as 1900-1910 men were graduating as mining engineers who were practically as well prepared to make geology or metallurgy their life work, as they were for mining. Gradually, however, the subject matter of mining geology and metallurgy became so enriched through research and development that separate curricula in them became worth while; their progressive development is the subject of another chapter. Mining curricula also began to be somewhat diversified, and schools in areas where coal mining was of outstanding importance began to offer options in coal mining, the earlier curricula having been chiefly aimed at metal mining. The petroleum industry began its meteoric rise about the same time as mineral instruction in this country, but little more of applied science attended its birth than had attended such ancient practical arts as copper and iron

Jan 1, 1941

By L. T. Hiaains

EVEN before the surrender of Germany, a gradual reduction in output of many of the small mining iseswises in the different countries of South America had occurred. Part of this was due to restricted purchases of strategic mineral supplies, and part to economic conditions. Inflationary tendencies have keen increasing since the war started; out in the past three years they have become serious. The difficulty in obtaining supplies, and labor troubles, has also combined to reduce production in many circumstances. British Guiana The Cuyuni Goldfields, Ltd., operating he Aleck Hill mine, is increasing their yanked mill to 500 tons. This appears be one of the few important new developments in South America during recent years. Brazil The big Volta Redonda steel plant was sported as being ready to start operations. Argentina Political troubles have restricted activities during the past year, and fuel short. ges have been so acute that surplus corn as burned in some instances. Practically all the tungsten producers ther closed down entirely or reduced

Jan 1, 1946

By Samuel S. Wyer

THE following abbreviations have been used in, the text: Cassier&apos;s, Cassier&apos;s Magazine. Eng. Lond., The Engineer (London). Eng. Mag., Engineering Magazine. Eng. and Min. Jour., Engineering and Mining Journal. Eng. News, Engineering News. Eng. Rec., Engineering Record. Engng., Engineering. Engr., The Engineer (Chicago). J. I. and S. I., Journal of the Iron and Steel Institute. Jour. F. I., Journal of the Franklin Institute. Jour. Assn. Eng. Soc., Journal of the Association of Engineering Societies. Mar. Eng., Marine Engineering. . Mem, Soc. Ing. Civ., France, Memoires de la Society des Ingenieurs Civils, France. Prac. Eng., Practical Engineer. Proc. Digs. Soc. of W. Pa., Proceedings of the Engineers&apos; Society of Western Pennsylvania. Proc. I. C. E., Proceedings of the Institute of Civil Engineers. Proc. I. 1M. E., Proceedings Institution of Mechanical Engineers. Trans. A. I. M. E., Transactions of the American Institute Mining Engineers. Sci. Am., Scientific American. Sci. Am. Sup., Scientific American Supplement. Zcitschr. d. V. D. Ing., Zeitschrift des Vereines Dentscher Ingcnieure.

Mar 1, 1905

Jan 1, 1971