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By A. B. Parsons

PUBLICATION of this little volume is a luxury that the Institute itself could scarcely afford. In truth, no engineer nor geologist, no assayer nor metallurgist would be likely to enhance his knowledge, improve his technique, or cut his own operating costs by reading this excellent translation of two booklets first published circa A.D. 1520. It is doubtful if the present enterprise would, in a practical or tangible way, "promote the arts and sciences connected with the economic production of the useful minerals and metals." And such, is the prescribed purpose for which the funds of the Institute should be spent. Fortunately for the Institute, the Seeley W. Mudd Memorial Fund is not so circumscribed; and the Fund Committee enjoys, greater liberty of action. The sponsorship by the Mudd Fund in 1942 of the publication of The Pirotechnia of Vannoccio Biringuccio, as translated by Dr. Smith and Mrs. Gnudi, was an innovation-indeed something of an experiment. Not only was the content of the volume significant mainly for its "cultural" and "scholarly" attributes; -but the format, an outstanding example of the fascinating art of bookmaking, bore no resemblance to the ordinary technical book. The Committee, frankly, was surprised at the enthusiastic reception accorded the volume. When a second edition was required, the Committee became convinced that the publication of material of this type, particularly if printed and bound in attractive form, was an appropriate avenue for utilizing a moderate proportion of the monies available from the Fund. The Bergbüchlein and the Probierbüchlein antedate by some years the first publication of De la Pirotechnia and of De re Metallica; but Georgius Agricola, the author of the latter work, made good use of the material in the earlier volumes. As pointed out in the Introduction, both

Jan 1, 1949

By John Sherbourne

Much valuable scientific research has been performed in recent years on the subject of phase behavior of hydrocarbons. ? 1-11 Engineers employed in petroleum production are interesting themselves in this work as well as in methods of applying the fundamental data available to the solution of their various problems. Recently a number of papers have been published in which applica-tions of phase behavior have been made to specific cases pertaining to critical phenomena.)12-16 Little effort, however, has been made in the literature to show the relation between changes occurring in the critical region and the more common phase behavior, therefore it is believed that a presentation of the fundamentals of phase behavior with reference to hydrocarbons is timely. Study of phase behavior is not new. In the metallurgical field, knowledge of heterogeneous equilibria has advanced tremendously, particularly with reference to solid-solid and solid-liquid behavior. Much is known about vapor-liquid equilibria too, but few engineers are familiar with this subject. ?

Jan 1, 1940

By Edmund Newton

THE steel industry of the United States has depended in the past almost wholly upon imports for its supplies of manganese. Many of the important domestic sources yield ores leaner in their natural condition than the foreign ores the steel industry has been accustomed to use. To make them available, therefore, either' the ores must be concentrated or the practice of the steel industry modified. Roughly 25,000 T. annually of high-grade manganese ores are used for dry batteries, for chemical purposes, and in other ways; while approximately 750,000 T. are required for making steel. By present practice, every ton of steel takes an average of about 14 lb. (1.8 kg.) of metallic manganese. This is generally added to the steel in the form of an alloy, the standard alloys being the 80-per cent. ferro-manganese and the 20-per cent. spiegeleisen. During the year 1917 286,000 T. of ferromanganese and 193,291 T. of spiegeleisen were made in this country, the former largely from imported ores; and 45,381 T.

Jan 2, 1919

By S. H. Cathcart

Price, production and drilling operations exceeded any year since 1930. A top price for crude of $2.55 was maintained from May 1 to November 6 and increased activity about coincides with that period. The average crude price for the year was: Bradford, $2.46; Kane-Butler, $2.34; Southwest Pennsylvania, $2.13. Production for the year exceeded 15 million barrels, an increase of about 2 million barrels over 1933. That this increase was more than justified by market demand is indicated by a reduction of 892,000 bbl. in stocks for the year. Two classes of data appear on Table 1, which are differentiated by footnote references. Where possible the .figures were obtained from individuals and companies that, from long acquaintance and varied contacts, are most capable of supplying an estimate where an estimate is necessary. The remaining data represent a rather careful compilation from all available published records (see p. 378). Drilling operations and production as summarized by the Oil City Derrick are as shown on Table 2.

Jan 1, 1935

By James Marsh

INTRODUCTION Economists have long expressed suspicion of the economic theory of natural resource exhaustion, even in writing articles which have contributed to it (1). Indeed, the gap which separates the pure theory from practical management seems unusually wide. It is doubtful whether a mine manager could possibly know enough about the relevant parameters of his mine to steer it along the optimal paths described by the theorists (2). Nevertheless, enough faith in the theory remains that mine managers are suspected of being a separate breed whose behavior must be studied in special courses using specialized text-books, collections of readings, and journals (3). The implied hypothesis, that mines and natural resource firms are managed differently than other firms, is the subject of this paper. In the next section the theory is developed and analyzed. In section III, I discuss the implications of the statistical results that have been obtained. Finally, conclusions are reserved for section IV. THE MODEL A key difference between the traditional theory of natural resource production and that of other forms lies in the set of variables which ire assumed to jointly determine the quantity of output the firm will produce. Output, in the non-resource case, is assumed to be a function of k clearly definable and distinguishable inputs or factors of production, viz., y = f(xl, x2, ..., xk), (1) here

Jan 1, 1977

By N. A. D. Parlee, E. M. Sacris

OXYGEN solubility in liquid silver has been well studied.1-6 It has been established that the solubility follows Sieverts' law reasonably well5'6 up to po2

Jan 1, 1968

By H. Reginald Hardy, Gary L. Mowrey

Field studies were conducted over a longwall coal mining operation to investigate the feasibility of using microseismic techniques to detect and to locate any areas of instability in the vicinity of the longwall. An array of geophones buried at depths of 3 to 8 m from surface were positioned approximately 130 m above the active area of the longwall panel. A mobile microseismic monitoring facility amplified, filtered, and recorded the microseismic activity sensed by the geophones. Microseismic events were detected at depths of at least 130 m and at horizontal distances in excess of 250 m from the source. Most events, which resembled decaying sinusoidal transients, had frequencies of 10 to 100 Hz, and particle velocities of 1 to 8 pm/s. Source locations for the 150 largest events were computed using a least-square travel-time-difference method. Both isotropic and unique wave propagation velocity models were considered when evaluating the source locations. Most of the events were computed to be within ± 30 m vertically of the coal seam and ± 15 m horizontally of the longwall face, when the unique velocity model was employed.

Jan 1, 1980

By J. C. Osler

The design of a tailings dam is a geotechnical engineering project of considerable scope. For the design, it is necessary to establish the engineering properties of the soil or rock strata which will support the dam and the tailings or other fill which will be used to construct the dam. The various field and laboratory investigations which are necessary to obtain the required design parameters are discussed in the paper and the use of these parameters to compute stability, settlement, and seepage are considered. The designer of a tailings dam can never assume an absolute knowledge of the properties of the foundation strata. Further, initial design assumptions are often approximate, particularly with regard to the distribution of pore pressures through and beneath the dam. Thus, the installation of performance monitoring instruments is recommended, since data obtained from such instrumentation can be used to check the stability of the structure both during construction and after its completion.

Jan 1, 1972

The Library of the above-named Societies is open from 9 A.M. to 9 P.M. on all week-days, except holidays, from September 1 to June 30, and from 9 A.M. to 6 P.M. during July and August. The Library contains about 55,000 volumes, including sets of technical periodicals and the publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library can render valuable service through correspondence; letters requesting information will receive special attention. The Library is prepared to furnish references and copies of articles on mining and metallurgical subjects; to determine the existence of mining-maps, and to furnish general information as to the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. The members of the Institute can be of service to the Library by forwarding copies of mining-reports, maps privately issued, and similar material, which will be classified, indexed, and made available to other members. Suggestions for additions to the Library, either by purchase or personal solicitation as gifts, will be welcomed. It is hoped that members while in the city will use the Library freely, and assurance is given that most careful service will be rendered to them. .

Jan 11, 1913

By J. B. Goddard

The discovery of rhenium on the ion exchange resin used at the uraniun in-situ leach operations at Palangana, TX, led to a laborabory study of possible recovery methods. Rhenium was present in small amounts in the ammonium carbonate leach liquors as the perrhenate anion, ReO4-. It concentrated on the anion exchange resin, which was a factor of 10 more selective for rhenium than for uranium. Various elution systems were investigated for stripping the rhenium from the columns after the uranium had been eluted with chloride or nitrate solutions. Although the per-chlorate ion was most efficient on a molar basis, nitrate ion combined the benefits of efficiency and low cost. A 3N or stronger concentration of nitrate containing up to 0. 5N H + was found to be the system of choice. A rhenium sulfide concentrate containing up to 14010 Re was obtained from these effluents by hydrogen sulfide precipitation. Preliminary experiments were run to produce rhenium metal powder by oxidation of the concentrate to NH4ReO4 followed by hydrogen reduction at elevated temperature.

Jan 1, 1984

By Floyd Kelley

THERE is an ever-increasing demand for furnaces with controlled atmosphere, due to the large quantities of steel being used in the automotive industry, such as the .high-chromium stainless irons, the 18 Cr, 8 Ni stainless iron and low-carbon steel sheets. The difficulties involved in the annealing of such materials, if they are to be kept absolutely free from oxidation, are many. It is possible to bright-anneal these steels in small laboratory hydrogen furnaces, using specially purified hydrogen and taking some additional precautions. In the first place, the insulation, usually of alumina or magnesia, holds small amounts of water vapor, which it is almost impossible to remove completely. Secondly, there is always condensation of water vapor in the cooling chambers of such furnaces, and with the continuous circulation of the hydrogen gas in the furnace, the water vapor is carried from the cooling chamber back into the heating chamber. This water vapor oxidizes the charge. Lastly, the supply of moisture is made sure by the diffusion of small amounts of air from the atmosphere into the furnace against the pressure of the hydrogen. The oxygen combines with the hydrogen and forms more water. Under such conditions there is, little gained by using specially purified gas, because it becomes contaminated after reaching the furnace.

Jan 1, 1931

By Henry E. Colton

Very little information has been published concerning the Tennessee coal-field. The State never appropriated over $600 per annum for a geological survey, and that was discontinued about 1870. Yet even with that small sum Dr. J. M. Safford made a

Jan 1, 1886

By Evert Hoek

SYNOPSIS It can be shown that the properties of intact rock are relatively unimportant in rock slope stability and that failures are controlled by structural discontinuities such as bedding planes, joints and faults in the rock mass. The frequency, orientation and inclination of these discontinuities as well as their strength characteristics are important factors to be considered in any rock slope analysis and their influence will be demonstrated by means of a number of practical examples. Methods for determining the mechanical properties of discontinuities will be reviewed and the interpretation of the strength test results for use in stability computations will be discussed.

Jan 1, 1971

By D. L. Martin, E. R. Parker

DURING the heat-treatment of silver specimens for tensile tests it was observed that the bars blistered and became brittle when heated in a hydrogen atmosphere. [ ] To check this unexpected result, a wide variety of commercial silvers were heated in hydrogen at 850°C, Only a few of the materials developed blisters, the most severe of which is the tube pictured in Fig. I. The microstructure of a cross section of the tube is shown in Fig, 2. The embrittlement is extremely severe at the edge; the blisters result from the severe deforma- [ ] tion of the surface material by large underlying gas pockets, The effects resulting from hydrogen embrittlement of silver have been observed by numerous investigators over a long time1,2,3 although it was only recently that a clear explanation was offered ,4 However, the damage resulting from hydrogen embrittlement has not been generally recognized; and it is of advantage to know more about this phe-

Jan 1, 1943

By Louis Stott

IT is well known that the oxide of beryllium was identified as a new "earth" in 17971 and the metal first isolated in 18272. The history of the many difficulties encountered by early investigators, the laboratory achievements of Lebeau3, Fichter4 and Oesterheld5, and the eventual development of methods for commercial production are well covered in the literature, particularly in the authoritative published work of Siemens and Halske6 reviewing their comprehensive investigation of the element. Accordingly it has seemed desirable to restrict this paper to the properties and uses of beryllium and its alloys.

Jan 1, 1936

Improved safety, economy, and flexibility-which translate into increased productivity-promote the case for greater utilization of diesel-powered equipment in underground coal mines. On the other hand, opponents of diesel use say that the alleged health hazards are not worth it. Who's right? The continuing debate was the focus of a special "Diesels in Underground Coal Mining" session held during the SME-AIME Fall Meeting in Lake Buena Vista, Fla., last September. Looking at the record to date, there are more than 20,000 diesel-powered units operating in underground mines throughout the world; more than 1000 are in Western European coal mines and 10,000 such units are in North American mines. Surprisingly, of the 10,000 North American units, only 200 are utilized in US underground coal mines.

Jan 4, 1979

By J. C. De Haven, 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 points'. 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° 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=4.16Å2 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

Jan 1, 1935

By K. A. Natarajan, I. Iwasaki

The effect of poisoning on the behavior of platinum electrodes in redox potential measurements in metallurgical systems was studied in the presence of such inorganic surfactants as cyanide and sulfide and such organic surfactants as dodecylammonium acetate, trimethyldodecylammonium chloride, potassium ethyl xanthate, and potassium diethyl dithiophosphate (Aerofloat®). These chemical species represent, more or less, typical constituents encountered in leaching, flotation, and sewage treatment systems. Triangular wave voltammetry was used as the experimental technique to study the nature of poisoned surfaces. Among the species studied hydrogen sulfide and dodecylamine were found to form a resistant surface film affecting charge transfer. Platinum electrodes appeared to have a weaker tendency to adsorb sulfide species in alkaline pH ranges, while cyanide, xanthate, and dithiophosphate affected the normal electrode behavior differently. Possible methods of reactivation of a poisoned electrode by mechanical cleaning are suggested.

Jan 1, 1974

NEW MEMBERS. The following list comprises the names of those persons who became members during the months of July and August, 1913: Members. ALDERSON, VICTOR C., Prest. of Colorado School of Mines :.Golden, Colo. ALLEN, JOSEPH W., Secy. & Treas. International S. & R. Co;, 42 Broadway, New York, N. Y. AMMON, ROBERT, Chief Sampler B. & M. Reduction Wks., Anaconda Copper Min.Co., Great Falls, Mont. BARBER, RAYMOND J., Min. Engr 234 Newbury St., Boston, Mass. BARDWELL, EARL S., Genl. Concen rator Foreman Boston & Mont. Reduction Plant, Great Falls; Mont.

Jan 9, 1913

By H. Scott

SINCE Böhler discovered, in 1903, on cooling certain alloy steels, the phenomenon of a new and lower temperature transformation than the usual Ar3_2_1 obtained by increasing the maximum temperature to which the material was heated, much has been published' connecting this phenomenon with a large number of dissimilar steels of high alloy content. From the fact that the transformation divides itself, taking place at two widely separated temperatures, it has been called a "split transformation." The, significant facts established by recent investigators' are: that when the' transformation occurs at the higher temperature Ar', troostite or a decomposition product is formed, and that when the transformation occurs at the lower temperature Ar", the resulting structure is martensite. The terminology Ar' and Ar" adopted here is that of Portevin.3

Jan 2, 1919