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COUNCIL OF EDUCATION OF AIME (Formerly Mineral Industry Education Division) Established as a Division January 15, 1932 Established as a Council February 26, 1957 John C Calhoun, Jr, Chairman 0 Cutler Shepard, Vice-Chairman Thomas A Read, Secretary-Treasurer Dept of Mining & Metallurgical Engrg University of Illinois Urbana, Illinois COUNCIL OF ECONOMICS OF AIME (Formerly Mineral Economics Division) Established as a Division December 15, 1948 Established as a Council February 26, 1957 Louis C Raymond, Chairman Lorin A Cranson, Vice-Chairman Henry T Mudd, Vice-Chairman Adam K Stricker, Jr, Vice-Chairman Paul F Yopes, Secretary-Treasurer U S Bureau of Mines Albany, Oregon

Jan 1, 1957

By J. C. McKinnell

The appraisal of an oil lease may often be mad,? through production decline analysis, which requires description of the functional relationship between the oil production rate and either cumulative production or time. Heretofore, attempts to define the function appropriate to a given set of production data have depended to some extent on subjective procedures. The purpose here is to introduce an objective solution, obtained by combining the principle of least squares with the theory of equations. MATHEMATICAL ANALYSIS The fundamental differential equation appropriate to a general class of decline curves may be written. Solution of Eq. 1 for general boundary conditions may be written in terms of either the cumulative oil production or time: These equations constitute the mathematical expression of the so-called hyperbolic decline. Their complete description for a given set of production data requires the numerical evaluation of the three parameters1.', n, D, and (go),. For the special case of n = 0, Eq. 2 becomes q. = (q.), - DiN with the corresponding expression in terms of time being q. = (qa),e...........(5) Similarly, for the special case of n = 1, Eq. 3 becomes with the corresponding expression in terms of cumula- tive oil production being q. = (q.),e " '.......(7) Eqs. 4 and 5 constitute the mathematical description of the so-called exponential decline; Eqs. 6 and 7 are the mathematical description of the harmonic decline.',' Returning to the hyperbolic expressions, Eqs. 2 and 3 may also be written, q: = sNp + b........ (8) and where a = 1 - n; s = (n— 1)D,(q0);"; b = (go):-"; a'=-n;s/= nD,(qo);"; and b' = (go);-. Note that both Eqs. 8 and 9 are linear in either time or cumulative production with respect to an exponential function of the production rate. In other words, a straight line relationship results for both variables when associated with the appropriate power of q,. This fact is of prime importance in the application of statistical analysis. . STATISTICAL ANALYSIS For a given oil lease, the time, production rate and cumulative production are recorded records. To establish predictive formulas from Eqs. 2 and 3, it remains to determine numerical values for the three parameters [n, D, and (q,) .] through an investigation of the past history. Upon interpreting a, s and b as parameters, Eq. 8 may be expressed for every time interval of interest, i, over the past history as follows. (q,): = s(Np), + b........(10) In general, Eq. 10 will not be satisfied exactly, because of the assumptions in the expression of Eq. 1, and the errors and anomalies universally associated with production data. It will instead define the residual, s(Np), + b- CO=d......(11) Squaring both sides and summing over all the data points, m, under consideration yields

By Samuel B. Christy

At the last meeting of the Institute, several contributions were made to the subject of miners' aid funds. Such matters will always form important factors in the administration of large industrial enterprises. From the frequently remote and isolated position of mining properties, it is a subject that often forces itself upon the attention of the mining engineer. Local conditions are usually so variable that no single method can be found equally well adapted to all localities. At the same time, a study of different types is often suggestive and valuable, and it is with this in view that these notes are presented. The Miners' Fund of New Almaden is a remarkably successful example of what may be done for miners by a wise and at the same time firm management, by simply directing their own efforts and without incurring any great expense to the stockholders,—a practical consideration not without importance in most cases. The quicksilver mines of New Almaden are situated at a distance

Jan 1, 1885

By M. N. Shetty, A. C. D. Chaklader

RECENTLY, it has been demonstrated that a considerable densification and interparticle bonding can be achieved if a pressure is applied to a powder compact while the material of the compact is undergoing either a decomposition reaction' or a polymorphic transformation.' The term "reactive hot pressing" has been coined to identify this process in which a phase change is combined with pressure to achieve interparticle bonding. This process is based on a principle which postulates that there is an enhanced reactivity and mobility of the molecular species at the phase-transformation temperature and this effect is utilized for interparticle bonding in powder compacts. This note summarizes the results obtained in an attempt to utilize this technique to produce ceramic-metal composites. In this case, a decomposition reaction of a compound (which after decomposition yielded an oxide) was used to achieve interparticle bonding in ceramic-metal composites. The reactive hot pressing was carried out in a Phillips induction heating unit, using either a graphite or a high-temperature steel die which functioned as both the susceptor and the hot-pressing component. The die was heated to the desired temperature in a helium atmosphere. All cermets produced by this technique were based on alumina as the ceramic phase. Different metal phases such as iron, copper, and chromium were used to study the effect of varying the metal phase on the properties of the composite. a Mono-hydrate (Boehmite) was mixed with different proportions of metal powders (-325 mesh) in dry condition in a mortar and pestle. No special precautions were taken for proper mixing. The mixtures were then compacted into a cylindrical form having an approximate dimension of 1 cm in diameter and 1 cm in height. For this compaction an ordinary

Jan 1, 1965

By AIME AIME

THE list of deaths during the year 1906 comprises the following names, the figures in parentheses indicating the year in which the persons named were elected to membership Members and Associates.-Arthur Vaughan Abbott (1882), William Anderson Akers (1889), R. Scott Allen (1905), George H. Arlett (1900), Thomas Septimus Austin (1883), Thomas T. Baker (1887), William Tittley Batchelor (1902), Charles Lowthian Bell (1897), Edgar Vallentine Bensusan (1892), George Lothrop Bradley (1874), Ernst Elmer Breisch (1896), Horace F. Brown (1895), James A. Burden (1876), Alexander B. Coxe (1880), George A. Crocker (1879), Albert W. Fiero (1886),

Jul 1, 1907

By C. H. Li, R. J. Stokes, T. L. Johnson

The effect of alumina particles on the nucleation and growth of cracks through a silver- chloride matrzx has been investigated. It has been found possible to promote fibrous cracking in dispersion-strengthened silver, chloride under notch-impact conditions at temperatures at which silver chloride alone cleaves brittlely The modification) of fracture beIzavzor is thought to be due to the relaxation of hydrostatrc stress beneath a notch by the nucleation of cavities near alumina particles. In recent years, composite or dispersion-strengthened materials have been studied primarily to understand their high resistance to plastic flow particularly at elevated temperatures. Dislocation models have been developed with which it is possible to deduce with fair success the effects of interparticle distance, particle size, temperature, upon yielding and creep behavior.l-4 Much less attention has been paid to the fracture behavior of these materials (with the notable exception of common structural steels) and little is known experimentally about the manner in which inclusions affect the nucleation and growth of cracks through a matrix. Nevertheless a beginning has been made in connection with fibrous cracking in ductile matrices where inclusions appear to play an essential ro1e.5-7 During the severe localized plastic deformation which accompanies necking in a tensile test, cavities are believed to develop at inclusions; these cavities subsequently grow and coalesce by plastic flow until separation is complete. It is of interest to consider whether inclusions can affect fracture behavior under loading conditions which restrict the plasticity of the matrix itself (for example, cleavage under conditions of a high imposed strain rate at low temperatures). It is particularly interesting to study these effects in a solid which shows a spectrum of behavior ranging from fully ductile to semi-brittle behavior. Such a solid is silver chloride whose mechanical behavior depends sensitively upon temperature and strain rate.'," The present paper is concerned with a study of the influence of inclusions (in the form of alumina particles) on the fracture behavior of silver chloride loaded uniaxially at low strain rates at room temper- ature and also under notch impact conditions over a wide range of temperature. In particular, it will be shown that the alumina particles can exert a startling effect on the ductile-brittle transition temperature of notched silver chloride and that the magnitude and nature of the effect depends upon both the quantity of alumina and the shape of the alumina particles. 1. EXPERIMENTAL PROCEDURE 1.1 Materials Used. Silver chloride powder of analytical reagent (AR) quality having an average particle size 6 was supplied by the Mallinckrodt Chemical Works (st. Louis, MO.). Acid washed 900 mesh alumina powder, designated A38-900, was supplied by the Norton Co. (Cambridge, Mass.). This powder was added to silver chloride in two forms: a) the as-received condition in which the individual particles were of random irregular shape; their statistical average size was 7; b) in a condition in which each particle was spherically shaped by a fusion technique. In this case, the statistical average particle size determined with the optical microscope was approximately the same (about 5p) but electron micrographic evidence indicated that many ultra fine particles were present in the spheroidized powder. 1.2 Preparation of Composite Materials. Silver chloride-alumina composites containing 2.5, 5, and 15 pct by volume of alumina were produced by the extrusion of mechanically mixed powders blended in a ball mill for 24 hr at room temperature. The mixtures were compacted at 50,000 psi at room temperature in the form of billets 3/4 in. in diameter and 1 in. long which were then extruded with a 16:l reduction ratio at 370°C through a radius-type steel die having a 5 deg lead-in angle. An extrusion temperature of 370°C was selected to ensure that all composites had sufficient plasticity to be extruded. Apart from this general requirement, the choice was arbitrary. 1.3 Microstructure of Composites. Attempts were made to check the distribution of alumina metallo-graphically by polishing transverse and longitudinal sections of the extruded rod. Specimens were wet-ground to 600 emery paper and lapped successively with 5 and 0.25-p grades of diamond paste. They were etched for 10 sec in 10 pct sodium thiosulfate solution and lightly polished in concentrated ammonium hydroxide. The most effective way to render the alumina particles and grain boundaries visible was to radiate the surface with intense white light to decorate the grain boundaries and the particle-matrix interfaces photolytically.

Jan 1, 1962

By C. E. Williams

THE Iron and Steel Division, A.I.M.E., is unique in this country in that it serves all phases of the iron and steel industries. Through its publications, its meetings, and its sponsorship of new technical developments in the industries, it has proved of great value. The various technical committees of the Division are the nucleus around which this service can be developed. The Blast Furnace and Raw Materials Committee has done excellent work. The need for beneficiation of iron ores is increasing and the economics of this operation are developing more and more in favor of increased activities. Ores that are slightly undergrade should be concentrated up to grade to supplant the present practice of mixing with higher-grade ores to bring up the average composition. Marginal ores that are not now being mined, or that are being mined and piled for future use, should be concentrated. The development of the use of sinter in the blast furnace, because of the elimination of fines, the advantage of better sizing of the charge, the resulting reduction of coke consumption, and increased output of pig iron per furnace, will make concentration and sintering become practical ahead of its natural time.

Jan 1, 1936

By F. G. Smith

A FEW years ago, the writer encountered a, problem that, at first, seemed to be due to peculiar conditions affecting grain growth. Large cups made from heavy metal failed in the first drawing operation in the process of making seamless tubes. The metal, as cast, appeared to be sound and strong; it rolled successfully and withstood the first cupping operation, but on the first draw it failed, with a crystalline fracture. The failure appeared in the slightly worked part of the bottom of the cup, and microscopic examination revealed exceptionally large grains. Knowing the general conditions governing recrystallization of brass, which were later published by Matthewson and Phillips, an investigation was outlined with the idea of including various conditions under which new grains might form, and which would include the effect that a previous anneal might have upon the anneal following. These conditions were produced by annealing specimens of brass at five different temperatures, indenting them with a 10-inn. ball under four different pressures, and then reannealing at each of the five temperatures five specimens each of which had been annealed at one of the five temperatures.

Jan 8, 1919

Last October a committee was appointed by The War Service Association of Manufacturers of Solder and Bearing Metals, Inc. to consider the report of the U. S. Bureau of Standards to the Conservation Division of the War Industries Board, a letter of the War Industries Board, and the discussions of this letter as reported at the meetings of association and to summarize the information thus obtained. The report of this committee has just been printed. The committee agrees with the Bureau of Standards that 99 per cent. tin can be used. It also finds that a very small amount of lead might increase the tendency of the bearing to crack and that lead has a hardening effect on babbitts up to a possible limit of 10 per cent. of lead. Still in the so-called genuine babbitts, in the presence of lead a certain proportion of low melting point eutectic is introduced which admits of the bearing being poured into thinner sections and is decidedly advantageous in the die-casting process in producing a much smoother casting. But the committee recommends that the Bureau of Standards thoroughly investigate this point. Lead-base babbitts, to give satisfactory service, must be carefully made of the proper raw materials. The bronze hearing that has been thoroughly tinned and containing the thinnest possible babbitt lining is now becoming recognized as the ideal bearing. The compositions, recommended by the committee are as follows:

Jan 2, 1919

Aamot, Olav Crone, Chem. Engr., Norsk Elektrokemisk, Kongensgt. 18, Oslo, Norway. '29 Abbott, Clarence E., V.P., Charge of Raw Materials, Tennessee Coal, Iron & R. R. Co., 1242 Brown-Marx Bldg., Birmingham, Ala. '04 Abel, Raymond L., Prof., Dept. of Pet. Refin., Univ. of Pittsburgh ..Pittsburgh, Pa. '28 Abel, Walter D., Cons. Engr 364 S. Cloverdale Ave., Los Angeles, Calif. '32 Abele, Louis T R.F.D. 1, Adamsville, Ohio. '31 Abell, Leo M., Ore Dressing Investigator, School of Mines Adelaide, S. Australia. '31 Abenius, Hakan V., Mine Supt., Bolidens Gruvaktiebolag Boliden, Sweden. '37 Aborn, Robert H., Asst. Met., Research Lab., U. S. Steel Corp., Lincoln Highway, Kearny, N. J. '19 Abraham, W. E. V., East India United Service Club, 16 St. James' Sq., London, S.W. 1,, England. '28

Jan 1, 1937

By Elmer W. Pehrson

Minerals have played a prominent role in the affairs of man and nations since time immemorial but with the advent of the industrial revolution, expanding use of the products of the mineral kingdom became synonymous with the material progress of mankind. Individuals and business groups have recognized this fact so have been aggressive in searching for and utilizing mineral resources, with notable success. Indeed, their achievements are primarily responsible for the present Machine Age. On the other hand, until recently the body politic has failed to grasp fully the essentiality of minerals although, at times, access to mineral supplies has been an important factor in the political maneuvers of nations. This chapter is concerned primarily with the broader political and economic relationships of mineral resources to the world economy, and with the internal and external actions of nations in the field of minerals. Many factors that condition the mineral economy of regions and the world as a whole, influence the internal and external affairs of individual nations. The more important of these are: 1. The nature of man's dependence on minerals. 2. The problems resulting from the unique characteristics of mineral occurrence. 3. Geopolitical concepts. 4. Minerals and world power. Actions of individual nations affecting their mineral economy seek two basic objectives : 1. Attainment and maintenance of prosperity. 2. Military security. Other objectives may be cited but on careful analysis they become integral parts or extreme phases of the two points noted above. For example, the twentieth century aggressions of the USSR, Germany, Italy, and Japan might be considered as direct bids for world power but they also can be interpreted as exaggerated or mistaken efforts toward military security and peacetime prosperity. Similarly, trade barriers, nationalization of industries, foreign exchange manipulations, taxation, monopolistic prac-

Jan 1, 1959

By F. N. Flynn

- Introductory IN 1882, The Arizona Copper Co. Ltd., acquired producing copper mines at Metcalf and Morenci (locally called Longfellow). Metcalf is situated a distance of 7 miles, and Morenci a distance of 6 miles from the general office of the company at Clifton, Ariz. A reduction works with five blast furnaces was built in the center of the town of Clifton in 1884 and operated until January, 1914. Concentration of oxidized ores was begun in 1890-1891, in a mill built adjoining the smelter, and in October, 1893, a leaching process was started for treating tailings from the oxide mill. A sulphide concentrator with 300 tons capacity was built at Clifton and started treating chalcocite ores in July, 1896. This was the first mill to treat low-grade copper-sulphide ores successfully. Another concentration mill for sulphide ores was erected at Morenci in 1900. The, sulphide mills are now being remodeled to treat ores by concentration and flotation, with a capacity of 4,000 tons at Morenci and 500 tons at Clifton. The leaching plant has not been running since September, 1914. The average yearly production from this company's mines and reduction works from 1885 to date has been: Pounds 10 years ended 1894 6,864,902 10 years ended 1904 20,439,614 10 years ended 1914 : 32,665,905 Part of year 1915, to Sept. 12 30,206,106 4 months of 1916, to June 15,964,840 June, 1916...: ? 4,900,000 Construction on a new smelting plant was started in February, 1912, and finished in February, 1914. In the Transactions, vol. 49, E. Horton Jones published "Unit Construction Costs from the New Smelter of the Arizona Copper Co., Ltd:," which fully describes the construction of this plant, with details of costs.

Jan 9, 1916

By Roger L. Beals, George A. Tweedy

I. INTRODUCTION. THE results of the cyanide-operations, given in detail in the following paper, show the progress that is being made at the Minas del Tajo. The old pan-amalgamation process, in operation up to and including 1905, while paying a profit on high-grade ores, was no longer able to treat profitably the ores in sight at that time, hence an alteration in the process was imperative. The success of this alteration is eloquently expressed by the following data Pan- Amalgamation. Cyanidation. 1905. 1907. 1903. Tons treated, . . 51,387 53,983 69,300 Value per ton (U. S. currency),. $10.75 $8.39 $8.28 Extraction, per cent., 65.00 88.50 S7.45 Extraction, per ton. .- $7.00 $7.4.; $7.24 Total cost, per ton treated, 6.50 4.311 4.01 Profit, per ton treated, . . 0.50 3.07 3.23.;

Feb 1, 1910

By Ian Wark

IN an earlier paper1 measurements of contact angles due to the effect of xanthates on mineral surfaces were reported. The solutions in which these measurements were made differed widely from those of modern flotation circuits. It is intended, however, by introducing, one at a time, the other principal reagents of flotation, to approach gradually the solu-tion composition of flotation liquors. The work now described is an attempt to determine the effect of one of the most important of these reagents-namely, sodium cyanide-on the establishment of air-mineral contact. The work has been carried out for the following companies: Broken Hill South, North Broken Hill, Zinc Corporation, Electro-lytic Zinc of Australasia, Mount Lyell Mining and Railway, and Burma Corporation. Since the effect of cyanide is inseparably connected with the alkalinity, the results cited below deal with the mutual effects of alkalis and cyanide. Alkalis alone exert a significant effect on the air-mineral contact but comparatively large amounts are required. Since the addition of a small amount of cyanide greatly decreases the degree of alkalinity necessary for the suppression of contact at surfaces of any of the minerals experimented with (except galena) and since alkalis are rarely used alone in practice, little attention has been paid to cyanide-free solutions. It was shown in the previous paper that, excluding the dixanthogen effect, whenever contact was practicable at all in an ethyl xanthate solution the angle of contact was 60°. There is, therefore, less necessity to measure equilibrium contact angles; in fact, the experiments herein described have generally been conducted with a view to determining whether contact is possible and not to measuring the actual value of the contact angle. The separations which have generally to be effected in dealing with complex sulfide ores are: (1) galena from sphalerite, pyrite, etc.; (2) sphalerite from pyrite and/or gangue minerals; (3) copper minerals from pyrite and gangue minerals; (4) pyrite from gangue minerals; (5) chal-

Jan 1, 1933

By T. F. Witheree

The Fletcherville Furnace was built in 1864 and 1865, making its first blast from August until October of the latter year, when it was blown out to prevent its " bunging-up." Repairs were made in time to enable it to be blown in again December 12th, 1865, the blast ending October 7th, 1866. Total product 1921.15 tons iron, an average of 6.8.2.5 tons per day, from ores yielding 44.8 per cent. Consumption of charcoal 223.2 bushels per ton of iron. The furnace journal up to this time shows no record of furnace dimensions, or temperature of the blast, but as near as can be ascertained, they were as follows, viz.: Height of stack, 42 feet. Diameter of bosh, 11 feet. Angle of bosh, 71/2 inches to 12 inches rise, about 58°. Diameter of open tunnel head, 42 inches. Number of tuyeres 3 ; each 3 inches in diameter. Dam 15 inches high. Tuyeres 24 inches high. Tymp 224 inches high. Diameter of steam cylinder, 20) inches. } Diameter of blast cylinder, 64 inches. } Stroke 5 feet. The engine is direct-acting horizontal non-condensing. December 26th, 1866, the furnace was again put in blast, having been considerably altered in the crucible; the height of stack, bosh, and tunnel head remaining as before. Six tuyeres were put in, three in each of the side arches. The hearth or crucible was rectangular in form, 3 feet wide x 31/2 feet long x 64 feet high. Inclination of bosh 58°. Height of tuyeres 26 inches; nozzles 21/4 inches diameter. Temperature of blast estimated to be about 500°.

By C. E. Mills

STUDIES of ground movement and subsidence resulting from mining operations cover a broad field. It is also a very important consideration and one that eventually affects nearly every mining operation of any extent. The damage to surface buildings, removal of mine surface plants and replacements of main hoisting shafts must reach an astounding expenditure were these cost figures available over a period of years. Were the subject one of mathematical formula and dependent only on the angle of draw of the walls or country rocks, the problem would be relatively simple. Consideration must be given to depth and extent of workings; structural conditions of the orebodies and enclosing country rock; physical properties of these same rocks, including schistosity, bedding, jointing, slips, dikes, faults, and other structural weaknesses. The method of mining, extent of openings, supporting pillars, and amount of moisture or water underground are other pertinent factors. With such a large number of variable factors, it is apparent that the subject of subsidence is one that must be based largely on experience and results at other mines where conditions are somewhat comparable. In presenting this paper, it is the intent to describe the progressive results of past ground movements at the United Verde, to bring out physical conditions largely responsible for this movement, but to refrain from theorizing on the ultimate extent of subsidence resulting from future mining operations.

Jan 1, 1934

By Howard Eavenson

THE low-volatile, or smokeless, coal field of southern West Virginia is in Fayette, Raleigh, Wyoming, Mercer, Summers and McDowell counties, in the extreme southern portion of the state, and extends into the adjacent counties of Tazewell and Buchanan in Virginia. McDowell County is the largest producer, with Fayette and Raleigh counties next. The total area of the field (Fig. 1) is approximately 1600 square miles, or 1,024,000 acres. The percentage of volatile matter in the various seams ranges from 15 to 26 per cent. The upper limit of true low-volatile coal is usually considered to be 23 per cent volatile matter; above this point, the coal usually is classed as medium volatile. This limit will be used in this paper.

Jan 1, 1931

CONTENTS [The Nature of Strain Markings in Alpha Brass (paper by J. E. BURKE and C. S. BARRETT, Met. Tech. Feb. 1948. TP 2327). ......................... 2 X Ray Studies of Twinning and Untwinning in Magnesium Alloys (paper by J. B. HESS and R. L. DIETRICH, Met. Tech. Feb. 1948. TP 2328) ................ 11 ]

Jan 1, 1948

By Oliver Bowles

WAR necessities have spurred inventive genius in many fields. A grinding mill without any moving grinding parts stirs the imagination. Among the new and striking accomplishments in the heterogeneous group of nonmetallic industrial minerals is the use of an electric arc to speed up manyfold the difficult and delicate task of drilling a microscopic hole in a diamond, the hardest of all known substances. Outstanding in the field of optical research is the ability that man has developed to improve upon nature by making in the laboratory optical crystals many times larger than those usually found in rocky crevices. These are merely samples of numerous events and circumstances of noteworthy import, many of which are recorded in this review. Termination of the second World War in 1945 permits an appraisal of the effects of the conflict and the probable effects of the coming restoration of a peacetime economy on the nonmetallic mineral industries. Some industries were stimulated greatly by the war, notably mica, quartz crystal, graphite, spinning asbestos, potash, fluorspar, barite, and refractories. The large-tonnage industries connected with the building trades, however, were forced to curtail their activities, except where their products were needed for wartime construction. Their reconversion to peacetime production will not be difficult.

Jan 1, 1946

[Aamot, Olav Crone, (M'29) Chem. Engr., Elektrokemisk, Raadhusgt. 23, Oslo, Norway. Abadilla, Quirico A., (M'38) Min. Engr., Dir. Bureau of Mines, Manila, P. 1. Abbott, Agatin, (J'40) Asst. Geol., Trench Mine, Patagonia, Ariz. Abbott, Clarence E., (M'04) Civil Engr., V.P., Tennessee Coal Iron & R.R. Co., 1642 Brown Marx Bldg., Birmingham, Ala. Abel, Raymond L., (M'28) Prof., Chem. Engrg., Univ. of Pittsburgh, Pittsburgh, Pa. Abel. Walter D., (M'32) Min. Engr., Div. of Corporations, State of Calif., 403 California State Bldg., Los Angeles, Calif. Abele, Louis T., (M'31) 4800 Patterson Ave.. Richmond, Va. Abell, Leo M., (M'31) Research Met., Mount Morgan Ltd., Mount Morgan, Queens., Australia. Abenius, Hakan V., (M'37) c/o Falu Gruva, Falun, Sweden.]

Jan 1, 1940