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By Anthony F. G. Lucas

BORN on Sept. 9, 1855, in the city of Spalato, Dalmatia. Austria, Antonio Francisco Luchich was the son of Francis Stephen Luchich, a prosperous shipbuilder and ship-owner of Lesina. His mother, Johanna Giovanizio, was known to the people of Trieste as a woman of unusual learning and piety. After receiving his high school training in Trieste, Antonio Luchich entered the Polytechnic Institute at Gratz in the year 1875, graduating two years later as an engineer. He then entered the Naval Academy of Fiume and Pola as a Midshipman, receiving his commission as a Lieutenant in 1878. In 1879, then 24, Antonio Luchich obtained a leave of absence from the Austrian Navy and came to Saginaw, Mich., to visit an uncle. He remained in this country and on May 4. 1885 at Norfolk, Va.. he became Anthony Francis Lucas. an American citizen.

Jan 1, 1945

By Hsun Hu

C. G. Dunn (Geneva1 Electvic Reseavclz Labo,vatory)-Dr. Hu16 has obtained a number of rolling and annealing texture results that partly agree with those of Dunn17 and Dunn and Kohl8 for experiments of a similar nature. I would like to discuss some of the points of agreement as well as some of disagreement and then present some unpublished data as a contribution to the work on textures. Firstly, there is agreement on the components produced during a 70 pct cold-rolling reduction of a (110) [001 ] single crystal; there is agreement on the forma- tion of a (110) [001] recrystallization texture provided recrystallization occurs at 800°C or higher; and there is agreement on the formation of (120) [001] components provided recrystallization occurs below 600°C. There is some disagreement on the low-temperature recrystallization since I also obtained a substantial amount of a (110) [001] component while the author obtained only (120) [001] components. I also discussed the differences between low- and high-temperature recrystallization (which included further annealing changes in the samples on long

Jan 1, 1962

By Guy Crane

I. INTRODUCTION THE geology of the Tintic mining district, fully treated, would occupy an elaborate monograph. This less comprehensive paper is devoted primarily to the occurrence and origin of the orebodies of the district, while space is given to those phases of the general geology only which seem necessary to a proper setting of such a discussion. The first geological report on the Tintic district to be issued was that by Tower and Smith, published in 1899, in the form of a paper in Part III of the Nineteenth Annual Report of the U. S. Geological Survey, and also as Folio No. 65, Geologic Atlas of the United States. About four years ago a second investigation was begun by Waldemar Lindgren and G. F. Loughlin, of the U. S. Geological Survey. With the exception of a paper on the oxidized zinc ores of the Tintic district by Mr. Loughlin, the results of their work are still unpublished. The writer's acquaintance with the district began in the fall, of 1913, and has extended over a period of about two years.

Jan 10, 1915

By H. E. Exner

This article is a critical review of the influence of surface preparation on crack formation at Vickers indentations in the test used by Palmqvist3-7 to evaluate the toughness of cemented carbides. Experimental results are presented which clearly show that grinding introduces compressive surface stresses into the cobalt phase and thus reduces the crack length. The deformed surface layer is removed by polishing and a stress pattern is approached corresponding to that in the bulk material. Cracks of maximum length are characteristic of this stress state. Deformation stresses can be removed by annealing above 800°C. On the basis of these results , sample preparation for the crack length test can be simplified, the accuracy of measurement is improved, and a simple and significani parameter is found to describe crack resistance of cemented carbides. FOLLOWING suggestions by Ammann and Hinniiber,1'2 Palmqvist3-7 developed a method for testing the toughness of cemented carbides using as a measure the sum of crack lengths at the four corners of a Vickers hardness indentation. This method has several advantages over the bend test commonly used in carbide technology: a) specially formed samples are unnecessary; b) sufficient information can be obtained from one sample; c) the scatter is relatively small; d) the range of actual values for commercial cutting alloys is wide. Thus, this test is both cheaper and more precise than the bend test. Nevertheless, Palmqvist's method is not widely used, mainly for two reasons: a) The relationship between crack length and the technological properties of the material (wear and shock resistance) is not clear. b) The crack length is strongly dependent on surface treatment. It is necessary, therefore, that surface preparation be very precise and reproducible, conditions usually hard to obtain. While any other simple mechanical test has this first drawback, the second became crucial in the application of the crack length method as a practical test. The reasons that this drawback could not be eliminated are, in our opinion, misleading and inconsistent interpretations of the influence of surface preparation on the crack length given in literature. In the following, after a short review of previous experimental results the interpretations given by different authors,4?'-11 cf. Table I, are discussed critically and a consistent explanation is presented on the basis of which improvements of the method of crack length testing are proposed. 1) PREVIOUS EXPERIMENTAL RESULTS In his first attempt to use the cracks at Vickers impressions as a quantitative measure of the toughness of cemented carbides, palmqvist3 calculated the work necessary to initiate cracks by the formula: Sk =k.Pk. [I] where k = numerical constant = 6.49, Sk = critical work to initiate cracks (gf cm), Pk = critical load (load necessary to initiate cracks) HV = Vickers hardness (kp per sq mm). The difficulties involved in experimental determination of the critical load were overcome by the observation that a linear relation holds between the applied load and the sum of the crack lengths at the four corners of the indentation. This linear function, given by Eq. [2] below, was confirmed by Dawihl and Alt-meyer9and by our experiments, see Fig. 1: I = a1.P +a2 [2] where 1 = sum of the crack lengths at a Vickers indentation, P = applied load, al, a2 = parameters dependent on the toughness of the alloy and the surface preparation. The critical load, Pk, is now given by a2, which can be obtained by extrapolating the load vs crack length line to zero crack length, see Fig. 1. This simple relationship, Eq. [2], led Palmqvist1,7 to a parameter which was more reproducible and easier to obtain experimentally than the critical work: the work, S300, put into the sample to produce an average crack length of 300 µm per indentation. This parameter is calculated using the formula: where the load, P3oo, giving a crack length of 300 µm, can be taken from the load-crack length plot, Fig. 1,

Jan 1, 1970

By Eugene Guccione

FOREWORD-At the SME-AIME meeting in Las Vegas this year, the SME Publications Board and the MINING ENGINEERING Committee decided that a fitting way of celebrating the United States' bicentennial would be to publish an article in ME covering the great men in American mining. After some discussion as to the inclusion of financiers -men such as William Randolph Hearst, J. Pierpont Morgan, etc.-the group agreed that the feature should be restricted to the "nuts-and-bolt people," e.g., mining engineers, geologists, mineral processing engineers. Thus, from the AIME All Institute Honors roll and from the SME Awards list, the group chose these 11 historical figures: Herbert Hoover, Daniel C. Jackling, Henry Krumb, James Douglas, Rossiter W. Raymond, Hal W. Hardinge, Seeley W. Mudd, Erskine Ramsay, Howard N. Eavenson, Robert A. Richards, Arthur F. Taggart. What follows is an account of each of these great miners' achievements and the problems they faced, and an assessment by some of today's mining leaders of the challenges that lie ahead.

Jan 7, 1976

By M. R. Geer, H. F. Yancey

John Grifien (Pittsburgh)—I wish to congratulate the authors on this paper, which, I am sure, will promote a clearer conception of the various criteria which have been advanced as measures of coal-cleaning performance. Their clear descriptions of the more important criteria that have been advanced and explanations of their meaning and application have been sorely needed and, if widely promulgated and followed, should remove much of the confusion which, heretofore, has been evident. I suggest that much of this confusion has also arisen from lack of common agreement as to the exact meaning of the words and terms used in our discussions of this subject. I am sure I have been equally guilty in this respect and suggest it is time that we select a committee to study vocabulary as well as criteria, so that common understanding and agreement can be had. Thus, I suggest, that the title of this paper should have used the words "coal-cleaning performance" and not "coal-washery performance." My understanding is that "washery" refers to a complete plant and it has additional functions to that of coal-cleaning, such as control of size, moisture, etc. Also, I do not agree with the authors that the formulas given in their paper, the Fraser and Yancey formulas, are necessarily the only ones that can be called efficiency formulas. When a dictionary is consulted one realizes that the words "efficiency" and "efficient" have not precise meanings but only very general ones and must be further defined for each particular use, if they are to have any precise meaning. To my mind, the first of the Fraser and Yancey formulas given should never be used as expressing "efficiency" alone but only by the fuller phrase which truly expresses the kind of efficiency it states, which is "coal recovery efficiency." For complete clarity we then need only define "coal" for the particular circumstances under which the formula is used. This would recognize the fact, fully explained by the authors, that the limits in coal qualities imposed by the market have imposed a factor—and a variable factor—which has influenced any answer obtained by this formula. Such a procedure makes it entirely practical and logical to use the values of any of the qualities of coal—ash, sulphur, phosphorus, specific gravity—or a combination of them to define what is coal for that particular use of the formula. Further, it is clear to me that the criteria to be used must be dictated by the objective in view and the use for which the data are obtained. The authors clearly point out that the Fraser and Yancey coal-recovery efficiency formula is influenced by three factors, "one is determined by the coal, one is dictated by market or use conditions, and one is an inherent characteristic of the cleaning unit itself." The formula which uses the inverse of misplaced material as a measure of efficiency is also a coal recovery efficiency formula and is influenced in like manner by these three factors. As the authors point out, both are useless in obtaining data which enables a direct and valid comparison of the performance of a given cleaning unit on two coals where the other two factors vary or of the performance of two or more cleaning units of different types unless the values of the other two factors are identical. Much of the confusion in our discussions of and literature on coal cleaning has come from failure to understand clearly this fact. Many such comparisons have been made from which erroneous conclusions have been drawn. I am, therefore, particularly glad to see the authors' emphasis on 4?-1e criteria which indicate the "sharpness of separation. I feel that these are the essential criteria

Jan 1, 1952

By D. M. Hausen

The amenability of a given vanadium ore to any given treatment depends largely on the mineralogic combinations of vanadium in the ore. Quantitative data on vanadium mineralogy provide not only an objective basis for selection of proper treatment, but also may eliminate many time-consuming amenability studies whose results are empirical, at best. Vanadium is distributed through the interstices of mineralized sandstone ores in the form of oxidized vanadates, reduced oxides, and silicates. Oxidized vanadates, e.g., carnotite, tyuyamunite, etc., are most readily beneficiated by simple acid leaching. Reduced oxides are more slowly solubilized, but relatively amenable to most acid treatments. The layered silicates, roscoelite, mixed layered mica-montmorillonite, and chlorite, are least amenable to most acid extractions, and constitute an assemblage of vanadium- bearing clays that are common to many sedimentary deposits. Vanadium is combined principally as layered silicates in the clay fractions of many sandstone ores. Mineralogic studies in this paper are largely confined to clay minerals, and to their amenability characteristics in low pH liquors.

Jan 1, 1985

By G. K. Burgess

G. K. BURGESS* and R. W. WOODWARD,? Washington, D. C.-From a metallurgical standpoint, there are several ways in which a reduction of the tin consumed in commercial non-ferrous and white-metal alloys can be effected. First, a reduction of the tin, content of the alloy; second, substitution of part or all of the tin content by some other metal; third, a substitution of a different type of alloy, which in some cases also involves a change in mechanical design. The Bureau of Standards has been studying these methods of conservation for tin alloys, particularly in regard to babbitts and bearing metals, bronzes, and solders. Much of the information secured by the Bureau was obtained from answers to questionnaires sent to manufacturers and users of these materials, so that, in general, any of the following suggestions or recommendations can be considered as being practical and as having already been thoroughly tried. Bearing Metals There is no question that the tin content of nearly all bearing metals can be reduced to some extent, and in some cases actually eliminated

Jan 12, 1918

By K. U. Snowden, J. N. Greenwood

CRACKS which form in lead exposed to fluctuating stress frequently follow a rectangular pattern. It is well known that under ordinary atmospheric conditions these cracks are intercrystalline. On the other hand after fabrication the crystal grains in lead are in general irregular polygons. The observed facts appear to be mutually contradictory. Re-examination of some lead failures has confirmed that the rectangular cracks are intercrystal- line. It follows therefore that under fluctuating stress some of the grains lose their irregular outlines and become approximately regular polygons of cubic type. G. R. Gohn and W. C. Ellis* suggest that this is due to recrystallization during the life of the part, in such a way that the new grain boundaries are aligned at 45 deg to the longitudinal strain prior to the formation of the fatigue crack. Experiments at Baillieu Laboratory—Some recent experiments carried out in the Baillieu Laboratory in conjunction with the Broken Hill Associated Smelters have thrown some light on this transition. A test piece of pure lead was polished chemically

Jan 1, 1959

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 M. W. Legatski, D. L. Katz

The best currently available description of the longitudinal mixing properties of a porous medium is an equation of the form which relates the effective longitudinal dispersion coefficient Dp to the molecular diffusion coefficient Do, the electrical resistivity factor F, the porosity <f> and a Peclet number. If the parameters dpa and m are determined for a porous medium of known porosity and electrical resistivity factor, then a dispersion coefficient may be estimated for a given flow rate and a given gas pair. A new method, featuring on-line gas analysis by thermal conductivity and on-line data reduction by analog computation, was developed and used to determine these mixing parameters for eight naturally occurring sandstones and two dolomite samples. The exponent m of the above equation was found to vary between 1.0 and 1.5. The characteristic length dpa in the above equation was found to vary between 0.25 and 1.9 cm, with an average value of 0.4 cm for sandstones. Measurements were made on two cores in which paraffin wax had been deposited by evaporation from a pentane solution. They indicated that the presence of an immobile phase such as connate water could increase the dispersion coefficients significantly. INTRODUCTION While the petroleum and chemical industries have studied the mixing of miscible liquids flowing in consolidated porous media and of miscible gases flowing in unconsolidated porous media, relatively little data have been presented to describe the mixing of gases flowing through consolidated porous media. Such data are of particular interest to the gas storage industry. For instance, the U. S. Bureau of Mines is storing large quantities of a rich helium-nitrogen gas in contact with a natural gas in a dolomite reservoir. Since the rich gas occupies only 15 percent of the total reservoir volume, it is essential that the extent of rich gas-natural gas mixing be predicted and understood as a function of rock properties, pressure and rate of movement. This investigation was concerned only with the determination of longitudinal dispersion coefficients. It is understood that a transverse dispersion coefficient, which characterizes mixing perpendicular to the direction of flow, may be an order of magnitude less than the coefficient characterizing mixing in the direction of bulk flow.5719 It should also be recognized that the use of any dispersion coefficient is in itself a simplification. It is necessary to assume that mixing in a porous medium may be characterized by the equation for flow in a single direction. A number of authors1 l8,19 have pursued the mixing problem, not in terms of the so-called "dispersion model" described by Eq. 1, but in terms of a "mixing cell model". This model supposes that a porous medium is constructed of a large number of small mixing chambers and that the concentration of the diffusing component within each mixing chamber is uniform. Fick&apos;s law (Eq. 1) assumes that there is no gross by-passing of one fluid by another, and that there are not stagnant pockets of gas in the system under consideration as discussed by Coats and Smith.8 These assumptions are not always valid for flow through porous media and it is important to recognize the limitations upon Eq. 1. The most serious limitation upon the assumption of Fick&apos;s law mixing in a porous medium is

By N. B. Wittman

The working of blast-furnaces is always of interest to many members of the Institute, for which reason I present an account of the working of the furnaces of the E. and G. Brooke Iron Company, of which I have had charge for the past four years. Although there are no phenomenal runs to record, there have been long periods of satisfactory work, and also periods—altogether too long—when one of our furnaces has behaved in a way which may be described as "nagging." All the conditions were apparently normal,but only a very light burden could be carried, which of course resulted in a high fuel-consumption to the ton of iron, as well as increased cost of labor. The two active furnaces of this company have the following dimensions and equipment : No 2. No 3. Feet. Feet. Height ....55 60 Diameter at bosh,.....- 15, 16 " hearth,...... 8 74 " stock-line,..10 91/2 Height of bosh,..23 23 " tuyeres,. 5 5 Diameter of bell,.7 6 Front,....closed open Both furnaces are blown with I. P. Morris condensing-engines, sim

Jan 1, 1890

By AIME AIME

MATTERS pertaining to mine ventilation were, taken up at the annual meeting Wednesday morning with E. A. Holbrook in the chair. In the absence&apos; of its author, G. E. McElroy, the first paper, entitled "Economic Size. of Metal Mine %Airways," was read by title by the chairman. The second paper, "Intermittent Mine Ventilation," by Oscar A. Glaeser, was &apos;abstracted by Dan Harrington. It related to metal-mining practice, being inapplicable to coal mining, of course. B. F. Tillson asked how the ,quantity of air was measured and con- trolled in the different splits and Mr. Harrington stated that an anemometer presumably was used and that split- ting was controlled by adjusting the steel doors to the desired position by means of screws. George &apos;S. Rice asked if the fan were underground, and Mr. Harrington replied that it was. Although he had at, one time recommended that it be placed&apos; on the surface, certain factors led the management to keep it underground, a. location that has several advantages in this particular case.

Jan 1, 1932

By Bezalel C. Haimson

Anna, Ohio, at the junction of Cincinnati, Findlay and Kankakee arches, has been the site of repeated and sometimes damaging earthquakes. As part of a seismicity investigation near-surface (0.15-1 m depth) overcoring strain measurements were conducted in four limestone and dolomite quarries surrounding Anna, the results of which suggest a complicated regional stress pattern, with changes in the maximum horizontal stress direction from N45ºE to N15ºW. Since such abrupt stress fluctuations are rather atypical in the Midwest and since the reliability of near-surface tests in defining regional stress had not been established, we decided to remeasure the stresses at the same locations but at greater depths (0-200 m) using the hydrofracturing method. Owing to the weak horizontal bedding planes of the Silurian shaly limestones and shaly dolomites and the relatively shallow depths, many of the tests yielded horizontal fractures, providing information only on the vertical principal stress (-0.029 MPa/m depth). However, sufficient tests in each of three testholes resulted in vertical hydrofractures to enable the calculation of all three principal stresses. Within 50-170 m depth the horizontal stresses in all three quarries appear to belong to a uniform regional Stress field defined by the following relations: [&apos;]Hmin = 5.1 + 0.014 D; [0] Hmax = 10.1 + 0.014 D, where D is depth in meters. The direction of [O]Hmax within 50-170 m depth is uniform at N70°E (±15º). The hydro- fracturing results obtained at Anna, Ohio are in agreement with the prevailing stress regime in the midcontinent both with respect to magnitudes and directions. The results suggest a possible thrust mechanism for a proposed NW-SE fault along which most of the earthquake epicenters have been located, and a left lateral strike-slip at greater depths. The focal mechanism solution of a recent major earthquake near Sharpsburg, Kentucky, some 200 km south of Anna, also indicates strike-

Jan 1, 1982

By D. B. Myers

The consistent upward trend in crude oil production prevailing in California throughout the greater part of 1929, was effectively checked in November by a curtailment program instituted by mutual agreement between operators in four of the major fields. This program artificially reduced daily production to approximately the same daily figure as prevailed in December, 1928. The large amount of deep drilling during the later part of 1928 and during 1929 has established a potential, however, which is far in excess of refinery needs in the state. Low prices for crude oil which prevailed in California during 1928 continued during 1929. General curtailment continued in the older fields in San Joaquin Valley. The number of wildcat and exploratory wells drilled throughout California was materially increased, but no major field was discovered unless the recent bringing in of the Ohio Oil Co.&apos;s Recreation Gun Club No. 1 well, near Venice in Los Angeles Basin, during the closing days of 1929 results in such a field. Significant developments during 1929 were: (1) The discovery of three deeper zones in the Santa Fe Springs field known as the O&apos;Connell, Clarke, and Hathaway; (2) Kettleman Hills development and unanimous agreement to restrict production; (3) developments along the Santa Barbara Coast and the drilling of tideland permits; (4) extensions of some of the older producing areas in the San Joaquin Valley; (5) the Lawndale and Santa Barbara Mesa structures, the former discovered in Los Angeles Basin in 1928, the latter in Santa Barbara County in 1929, proved to be failures; (6) intensive exploration throughout the state and the drilling of a large number of deep wildcat wells; (7) discovery of oil by the Ohio Oil Co. in the Los Angeles Basin at Venice; (8) Long Beach and Ventura Avenue fields maintained steady production throughout the year. As a natural sequence to the discovery of high-gravity oil fields in Kettleman Hills and at Elwood in 1928, a tremendous amount of exploratory work was done in 1929 in areas underlain by rocks of lower Miocene age, particularly along the Santa Barbara Coast area, the San Joaquin Valley, and the Salinas Valley, where the Vaqueros and Temblor sands were considered to hold possibilities for production.

Jan 1, 1930

By W. L. Watts

The existence of petroleum in California has been known for many years. From time immemorial the California Indians used this mineral, in the form of asphaltum, for various purposes. In the early history of the State the Catholic fathers utilized it for roofing their missions and other buildings. It is said that in 1855 or 1856 Andreas Pico distilled petroleum on a small scale for the San Fernando Mission. He obtained his crude oil from Pico canon, near Newhall, in Los Angeles county; and he was probably the first refiner of petroleum in this State. In 1856 a company commenced work at the La Brea ranch, in Los Angeles county, and tried to refine the crude oil. In 1857 an attempt was made to produce illuminating-oil from crude petroleum at Carpenteria, in Santa Barbara county; and there are records of similar attempts in other localities previous to 1860; but none of them were successful. The first scientific report on petroleum in California was made by Prof. B. Silliman, who published his researches in 1865. He spoke favorably of the possibility of obtaining petroleum in remunerative quantities in this State, and gave the results of his experiments in the fractional distillation of California petroleum. The next decade was marked by a considerable oil-excitement in California; and a great many companies mere formed for the purpose of petroleum-mining and for distilling crude oil. In most instances these companies did not meet with success; but it must be remembered that the pioneer oil-miners did not

Jan 1, 1900

SAN FRANCISCO LOCAL SECTION Executive Committee G. HOWELL CLEVENGER, Chairman C. W. MERRILL, Pace-Chairman JAMES C. RAY, Secretary-Treasurer, 1235 Webster St., Palo Alto, Cal. F. W. BRADLEY ANDREW C. LAWSON Meets on the second Tuesday of each month Farewell Dinner to H. Foster Bain H. Foster Bain, Who has gone to London to assume the editorship of the Mining Magazine, was tendered a farewell dinner by the San Francisco Sections of the American Institute of Mining Engineers, the Mining and Metallurgical Society of America, and the Engineers&apos; Club, on the evening of Mar. 9, 1915, at the Hotel Bellevue, San Francisco, 85 members being present. George H. Clevenger acted as Toastmaster and the following toasts were responded to: Bain and the Mining Industry, E. H. Benjamin. Bain, the Geologist, A. C. Lawson. Bain, the Man, F. W. Bradley. Bain, the Friend, C. W. Merrill. Bain, the Schoolboy, C.. F. Tolman. The Frontispiece and Flow sheet from the souvenir program, designed by James C. Ray, Secretary of the Section, are reproduced herewith.

Jan 5, 1915

By David B. Burrows, Rlkl Kobayashi, Norman L. Carr

The viscosity of hydrocarbon mixtures, whether in the gas or liquid phase, is a function of pressure, temperature, and phase composition. This paper presents methods for the prediction of the viscosity of the gas or less dense fluid phase over the practical range of pressure, temperature, and phase compositions encountered in surface and subsurface petroleum production operations. The correlation necessary to predict the effect of pressure on viscosities is presented in Part I. Serious discrepancies in high pressure gas viscosity data in the literature are discussed. The application of the correlation to predict absolute viscosities is discussed in Part 11. Auxiliary correlations are presented to enable calculations of viscosities from a knowledge of the pressure, temperature, and gravity of the gas phase. INTRODUCTION A knowledge of the viscosity of hydrocarbon fluids is needed to study the dynamical or flow behavior of these mixtures through pipes, porous media, or more generally wherever transport of momentum occurs in fluid motion. Since flow is predominantly in the laminar region in petroleum reservoirs, the influence of fluid viscosity on this flow is especially important. As early as 1894, Onnes1 and Onnes and de Haas&apos; noted that the viscosities of homologs under corresponding states could be correlated. The theorem of corresponding states has been further developed and applied to the viscosity of pure, nonpolar gases under pressure by Comings, Mayland, and Egly.3 It was demonstrated that the viscosity ratio could be expressed rather closely as a function of reduced pressures and temperatures, 1.e.: µ/µ1 = f( TR2 PR) ........(1) temperature, absolute units where: TR =------------------------------ ------ critical temperature. absolute units _pressure, absolute units critical pressure, absolute units µ = viscosity of gas at reduced temperature TR and reduced pressure PR µ1 =. viscosity of gas at atmospheric pressure and at temperature TR Serious discrepancies in the viscosity of pure hydrocarbon gases at high pressures have been called to Our attention by Comings, and and Egly. They made a careful analysis of the following methods commonly used to measure gas viscosities: 1. Oscillating disc viscometer4,5 2. Rolling ball viscometer6,7 3. Capillary tube viscometer12 On the basis of their analysis of the problem and their experimental data on the viscosities of methane, ethylene, carbon dioxide, and propane, they preferentially selected data obtained by the capillary tube viscometer to develop their viscosity correlation. Since then a need has existed to verify the experimental technique of Comings, Mayland, and Egly for the determination of viscosities at high pressure; to extend the data to mixtures of hydrocarbons; and to extend the range of their correlation to include higher pressures. Using the correlation procedure of Comings, May-land, and Egly, the prediction of gas viscosities is resolved into the correlation of the effect of pressure, temperature, and composition on the viscosity of hydrocarbons and their mixtures and the prediction of viscosities of mixtures of hydrocarbons and other natural gas components at one atmosphere pressure.

Jan 1, 1955

By D. L. Rainey, E. R. Goter, W. R. Hudspeth

THE area in which spodumene-bearing pegmatites occur extends from Gaffney, S. C., in a northerly direction to Lincolnton, N. C., a distance of about 16 miles. The zone averages 2 miles in width. Interest in this area was first aroused by the discovery of small amounts of cassiterite in the pegmatites and in greissen which occurs on the walls of some of the pegmatites. Attempts were made from 1880 into the 1920&apos;s to mine and concentrate cassiterite, but there were no successful operations. In 1935 L. M. Williams became interested in the area and began prospecting by trenching and sinking several small shafts. He gradually gained control of a considerable acreage south of the city of Kings Mountain, N. C. Mr. Williams states that he produced some ore from a shaft which he shipped to the Maywood Chemical Co. in the late 1930&apos;s. In 1937 G. H. Chambers of the Foote Mineral Co. visited the area and examined several properties, but the lithium market was too small to support the necessary concentrating plant.

Jan 9, 1953

By L. Messulam, A. S. Appleton

Iwo major studies of the Fe-Cr-C system are available in the literature. The earlier one of Kinzel and crafts&apos; forms the basis for the data most commonly quoted in works of reference (e.g., Metnls HandDook) though the later work of Bungardt el a1.&apos; is more extensive and amenable to analysis in terms of isothermal sections and so forth. However it is evident from examination of either of these studies that the delination of phase boundaries on the basis of the data obtained can only be very approximate. Indeed in several instances the data are so inconclusive that this delineation is a matter of opinion. This note is to report an analysis of experimentally determined carbon activity data in this system, which, originally intended as a means of checking the self-consistency of the data for a number of alloys, enables some conclusions to be drawn concerning the 10503C isothermal section of the iron-rich corner of the system as deducible from the data of Bungardt

Jan 1, 1967