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By W. F. Wheeler

In the study of the coals of Illinois now being carried on by the State Geological Survey, an attempt is being made to determine the most satisfactory basis of comparison between different coals. The following discussion is based upon work done for the Survey in the laboratories of the State University and under the general direction of Prof. S. W. Parr. "Pure coal" has been defined by Mr. A. Bementl as ash- and moisture-free coal, and the use of this pure coal" as a basis for comparing different bituminous coals has lately been much discussed among engineers in the middle West. By some the B.t.u. of the pure coal is being used to check calorimetric results, and to calculate the calorific value of different coal-samples from the same seam, for which purposes it is necessary to assume—first, that the composition and calorific value of pure coal from different parts of the same coal-seam are uniform, and, second, that these values remain constant after the coal is mined, both of which assumptions there are reasons to believe are inconsistent with the facts. Certain variables are included in pure coal, as ordinarily defined, and disregard of them may lead to serious error. In any event, where delicate shades of difference are involved, no sure interpretation of results car] be made, unless these variables be eliminated. As a basis of comparison between coals, ash- and moisture-free coal is much to be preferred to " dry coal," and still more is it to be preferred to moist coal," as ordinarily reported in analyses. There are, however, two constituents other than ash

Jan 1, 1908

By B. H. Kear, S. M. Copley

Stress-stvain curves are presented for Ni3Al (y') cvystals in several ovientations, deformed in tension and compression at constant displacement rate, at temperatures from 70° to 2000°F. Both the yield stress and wovk havdening increase with temperature, with the magnilude of the effect dependent on ovientation. The yield stress maximum occurs at 1500°F in [001], at 1400°F in [011], and at 1200°F in [111]. The suppression of the yield stress peak in [011] and [111] orientatiorzs is due to the onset of cube slip, rather than octahedval slip, a1 elerated temperatures. The temperature and orientalion dependence of work hardening in nominal single slip orientations corvelates with changes in the CRSS ratio for octahedral slip and cube slip, in agreement with a model for work hardening based on pinning of screw dislocalions by cross slip from an octahedral plane into a cube plane. It is concluded that the unique plastic properties of y' have a decisive influence on both ductility and strength characleristics of y +y' nickel-base superalloys. It has long been recognized that the strength of y + y' nickel-base superalloys depends on the precipitation of the y' phase [basically Ni3(Al,Ti)]. This paper presents new data on the strength characteristics of single crystals of simple y' (Ni3Al), and forms the first step in a systematic program aimed at elucidating the mechanisms of hardening in the complex commercial alloys. 1) EXPERIMENTAL PROCEDURE Single crystals of off-stoichiometric NiA1 were grown from the melt under vacuum by a modified Bridgman method. The melt was poured into a preheated alumina mold and crystal growth was promoted from one end by gradient cooling. The crystals were homogenized by annealing in hydrogen at 2400° F for 72 hr followed by furnace cooling. Chemical analysis of samples taken from several crystals gave an average composition of 88.2 wt pct Ni. Spectrographic analysis gave as the principal impurities in weight percent— Si (0.02), Mg (0.01), Fe (0.02), Ti (0.002), Cu (0.008), and Co (0.03). Tensile specimens with specifications as in Fig. 1 were prepared by a series of operations involving electrical discharge machining, precision grinding, and electropolishing. Compression specimens with dimensions 1/4 by 1/4 by -3/4 in. were prepared in a similar manner, except for the initial shaping operation using a precision cut-off wheel/two-circle goniometer unit to give selected crystal orientations. Specimens were deformed in a Baldwin-Wiedemann testing machine with furnace attachment, using a strain rate of 5 x 10-4 sec-1. The strain measuring device consisted of extension arms attached to the tensile grips (or compression plattens) at one end and leading out of the furnace to an LVDT at the other. Temperature was controlled by a thermocouple placed in contact with the specimen. According to the known phase diagram for the Ni/A1 system,' when an alloy of the specified composition is cooled from the melt, primary y (nickel solid solution) dendrites grow at the expense of the liquid phase, which becomes enriched in aluminum. At the eutectic composition the remaining liquid freezes as a two-phase mixture of y + y' (Ni3Al). Upon further cooling, a solid state transformation occurs, involving the precipitation of y' in the primary dendrites, and the complete transformation of the eutectic mixture to massive y'. The as-cast structure consists, therefore, of y + y' dendrites with interdendritic regions of massive y', i.e., transformed eutectic, Fig. 2. 2) DISCUSSION OF RESULTS 2.1) Stress-Strain Curves. Fig. 3 shows tensile stress-strain curves for crystals in orientations close to [001] deformed at temperatures from 70° to 2000°F. Both the yield stress and total elongation are strongly temperature-dependent. At 70°F, easy glide is absent, and the work hardening coefficient BIT - G/300. At T > 1500°F, the negative slope of the stress-strain curves is due to pronounced necking in the crystals. The yield stress maximum at 1500° F corresponds with a minimum in the ductility, Fig. 4. The extensive duc-

Jan 1, 1968

IN the preceding chapter on thermochemistry and the reactions in and between metal and slag phases and in the following chapter on fuel combustion the main emphasis is placed on the equilibrium or "static" conditions. This equilibrium viewpoint is not concerned with the rate of change in the process or with the mechanisms or paths followed between initial and final states. The questions of just "how it works" and "how fast" belong to the kinetic aspect of any process; their answers are helpful in speeding up or slowing down and thus controlling its operation, and also in understanding its limitations. Any treatment of kinetic factors in the open hearth such as is attempted here and in Chapter 22 must at present be largely qualitative and incomplete. We are only beginning to get quantitative data on rates of reaction and diffusion at high temperatures, as indicated in Chapter 15. Empirical data in the literature on furnace operating rates do not help much to illuminate the details of gas-flow patterns and the complexities of heat flow in the many parts of the furnace system. This chapter is intended to give the reader an introduction to the problems of the flow of gases through the furnace system and the flow of heat in this system. An adequate discussion would require several times the space available here; it is possible here only to outline a few fundamentals and to indicate some of the conditions of heat and gas flow peculiar to the open hearth. Several good general treatments of these subjects may be found in the literature (see references at the end of the chapter). For the designer of open-hearth furnaces, the principles of gas flow are of paramount importance. They are also important to the operation of the process, at least to the extent of a general qualitative picture of the movement of gases in the system. MOTION OF GASES IN FURNACE DUCTS Fluid [flow] in general can vary between the extremes of laminar or streamline flow with a minimum energy loss, to irregular

Jan 1, 1964

By R. H. B. Jones

THIS paper reviews pertinent geology of the Biwabik iron formation, Mesabi Range, Minnesota. This iron formation is divisible into four members. Each member is distinctive and contains marker horizons, which are recognizable throughout all phases of alteration from lean, fresh rock to high-grade iron ore. Some beds have a larger magnetite content than others. During the process of ore genesis, which is essentially an oxidation process, the magnetite content is lowered. Alteration from iron formation to ore includes both oxidation of iron minerals and silica removal by leaching and these distinct processes progress at variable rates for different locations and structures. Magnetic intensities, of each horizon of the iron formation are dependent chiefly upon its preoxidation magnetite content, upon the subsequent degree of oxidation, upon the character of the enclosing rocks, and on the extent of fracturing, folding, or faulting. The results of a number of magnetic surveys are described and are correlated with results of drill-hole and mine exploration and development. The magnetic anomalies obtained are discussed in relation to phases of formation of ore within the iron formation.

Jan 1, 1946

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 furbish 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 10, 1913

By Carl H. Beal, E. D. Nolan

In February, 1918, the conclusion was published by Lewis and Beal "that wells of equal output on the average will produce equal amounts of oil in the future, regardless of the ages of the wells." This conclusion was based upon the study of data collected principally in Oklahoma and was not known at that time to be true for other oil fields. An abundance of statistical proof was later collected by the senior author of the present paper, which showed that the conclusion was undoubtedly well founded and that it applied to other fields as well. Accordingly, it was later restated2 as the "law of equal expectations" as follows: "If two wells under similar conditions produce equal amounts during any given year, the amounts they will produce thereafter, on the average, will be approximately equal, regardless of their relative ages." Although only scanty data from the California oil fields were available at the time this publication was prepared, sufficient information was analyzed upon which to base the insert on Fig. 80, which showed beyond a doubt that the law held at least for a part of the Midway oil field in California. Recently the authors have collected more complete data in California, and it is the purpose of this paper to explain the method used in demonstrating the truth of the law and, in addition, to give several methods by which curves constructed in accordance with this law can be used in a practical way with ease and accuracy. The Family Curve The law of equal expectations means that each individual of a group of wells producing under similar conditions will decline along approximately the same type of curve, the rapidity of decline varying with the output

Jan 1, 1921

By G. J. Skoronski

The training school program for operation of a Grate-Kiln System is a comprehensive, detailed presentation of equipment design and maintenance combined with operating philosophy and procedures. An outline is presented relating the sequence of required instruction. The program is initially concerned with acquainting personnel with terminology unique to pelletizing and the Grate-Kiln System. Depending on the scope of each individual contract, a discussion describing process equipment and the process flowsheet is conducted. The process flowsheet discussion describes preliminary unit operations. Grate-Kiln System unit operations, process gas flow and gas flow control philosophy, and system pressure relationship.

Jan 1, 1977

By Y. Wang, M. M. Singh, H. L. Hartman

Knowledge of the state of stress at the bottom of a drillhole is of practical importance in rock drilling, since the induced stresses must exceed the strength of the rock in order to cause fracture. This note reports on a numerical method to determine the stress distribution at the bottom of a borehole induced by a static bit load and overburden and fluid pressures. The procedure adopted is similar to that for the plane-strain, discrete model employed by Harper and Ang.1,2 The rock medium is considered to be homogeneous, isotropic, and elastic-perfectly-plastic. METHOD OF ANALYSIS AND PROGRAMMING The discrete model adopted consists of two types of points: mass points and stress points. The configuration and numbering notation are depicted in

Jan 1, 1967

By A. E. Jenkins, A. Jostsons

Isothermal sections of the Ti-0-H phase diagvam at 600°, 700°, and 800°C have been constructed from equilibrium hydrogen pressure measurements over a range of Ti-0-H alloys containing up to 34 at. pct 0. Oxygen reduces the hydrogen solubility at fixed hydrogen pressure but increases the terminal solubility in the a solid solutions at the a/(a + P) phase boundary. Metal-lographic studies of alloys annealed below the eutectoid temperature show that oxygen also increases the ter-ninal solubility of hydrogen in the a solid solution in equilibrium with the hydride phase. The effect of oxygen on hydrogen solubility is discussed in terms of the electronic and geometric structure of interstitial solid solutions. THE isothermal solubility of hydrogen in a Ti-0 alloys at 800°C has been measured by Hepworth and ~chuhmann' who subsequently used ternary Gibbs-Duhem integrations to calculate oxygen activities in binary Ti-0 alloys. The present study aims to extend Hepworth and Schuhmann's measurements to alloys richer in oxygen and to a range of temperatures. This paper presents the results of hydrogen equilibrium pressure/concentration measurements in Ti-0 alloys as well as observations on the effect of oxygen on the terminal solubility of hydrogen in a titanium. The thermodynamic properties of binary Ti-0 alloys, derived from these measurements, will be published separately.' EXPERIMENTAL METHODS Specimen Preparation. Ti-0 alloys were prepared from iodide-refined titanium and titanium dioxide obtained by hydrolysis of redistilled titanium tetrachlo- ride. Specimens containing up to 16 at. pct 0 were prepared by electromagnetic levitation3 whereas a conventional tungsten arc furnace with a water-cooled copper hearth was used to melt oxygen-rich alloys. The specimen homogeneity was indicated by the constancy of lattice parameters of samples from various parts of the ingot as well as by the sharpness of the reflections on X-ray powder patterns. Oxygen-rich specimens in the composition range (20 to 34 at. pct), where ordering has been ~bserved,~ were annealed for 300 hr at 600°C prior to use in hydrogen solubility measurements. Apparatus. The hydrogen pressure/concentration measurements were made with a modified Sieverts apparatus shown diagrammatically in Fig. 1. Specimens were placed in a clear silica tube and impurity pickup by direct reaction with silica was prevented by lining the heated end of the silica tube with thin molybdenum sheet. A double silica tube was required to eliminate loss of hydrogen by diffusion through silica at high temperatures and high hydrogen pressures, the space between the tubes being maintained at a hydrogen pressure equal to that above the specimen. Hydrogen was purified by diffusion through a Ag-Pd tube.= Hydrogen pressures were measured with a mercury McLeod gage in the range 0.001 to 4 Torr

Jan 1, 1968

By J. J. Taber, I. S. K. Kamath, R. L. Reed

Alcohol floods of consolidated sandstone cores have shown the process to be strongly dependent on the phase behavior of the particular alcobol-oil-water system used. This means that in many cases the mechanism does not conform to the idea of a piston-like displacement. Instead, it is found that by changing the alcohol it is possible to change the relative velocities of the oil and water and, in fact, the entire mechanism of the process. The effects of rate, viscosity, initial saturation, distance travelled and hysteresis of relative permeability on the alcohol flooding mechanism are discussed. INTRODUCTION Reasons for interest in the use of alcohol to miscibly displace oil and water from a porous medium appear in the existing literature.l-7 The mechanism of the displacement has been considered and the apparent implications formulated into a theory which presumably would enable one to predict the essential features of the process.6 Unfortunately, most of the reported experiments have been performed with unconsolidated or artificially consolidated sands. With these systems some of the noteworthy facets of the process are obscured and resulting data appear uncertain. It is the purpose of this paper to show how the use of consolidated sandstones has led to revision of the mechanism and, hence, the theory of alcohol flooding. The practical result is increased pessimism toward the possibilities of commercial application of the simplest form of the alcohol-slug process. However, elucidation of the mechanism has made it possible to define the essential characteristics of a system of slugs which will behave in a nearly piston-like fashion and, thus, yield the best possible result. EQUILIBRIUM PHASE BEHAVIOR Fig. 1 is a diagram of the ternary system isopropyl alcohol (IPA)-Soltrol-calcium chloride brine. Brine was used to prevent plugging of the core and calcium chloride was used because sodium-chloride brine exhibits a solid phase with Soltrol and IPA. If alcohol is added in increments to the immiscible mixture of water and oil represented by Point A, the path followed by the successively equilibrated samples will be on the Line ABC and pass from the immiscible region to the miscible region by crossing the binodal curve at B. Consider the intersection D of this path with the tie Line EF. The quantity of oleic phase is proportional to the Segment ED and the quantity of the aqueous phase is proportional to DF. Compositions of the two phases are specified by Points E and F. It is clear that in the case shown the oleic phase is diminishing and entirely disappears when miscibility is achieved. Such will

By Charles F. Manness

In the great increase of product which has been accomplished in the American Bessemer plant, through improvements in machinery and refractories, and by more perfect skills in their manipulation

Jan 1, 1881

By J. M. Hassler

Nowhere can there be found a more misleading statement than the old one that "Iron can be manufactured cheaper in the South." During the past decade ironmakers and users of iron have heard varied and sundry stories of the wonderful resources of the Birmingham district, including abundant ore and coal fields, cheap labor, a wonderful climate and similar industrial Utopian statements. Birmingham represents the major portion of the iron business in the South, and as Birmingham fares so goes the iron business of the South. The intent of this paper is to shed some light on the actual conditions surrounding ironmaking in the South, especially in the Birmingham, or North Alabama, district. By a presentation of facts it is desired to point out that the "cheap iron" of the industrial South is a thing of the past, primarily because of increased labor cost and because labor is radically different in performance to what it was years ago. Also, because most of the raw materials needed in ironmaking that would be classed better than inferior are gone. Important Factors The several important factors that have been responsible for this change are : 1. Shrinkage of the iron business in the South. 2. Increased labor cost. 3. The development of the South, with an industrial trend, without a substantial increase of its own iron-consuming market. 4. Increased freight rates, which has narrowed the market that might be reached from this district. 5. Depletion of the better grades of raw materials, both ore and coal. Shrinkage of Iron Business in South.—Table 1 was prepared in early 1936 and revised in 1937, of blast-furnace units in the North Alabama district, considering the year 1936 compared with a maximum number of furnace units of previous years, the peak point being very near the year

Jan 1, 1937

By Cyril Smith

A STUDY of the precipitation-hardening of copper steels1 led the authors to investigate malleable iron containing copper, for the low-carbon ferritic matrix in malleable iron should lend itself admirably to precipitation-hardening. It was soon found that in addition to rendering malleable iron susceptible to improvement by precipitation-hardening treatments, copper has another potentially useful effect as an accelerator of graphitization. Brief mention of these effects was given in a general paper by Lorig and one of the present authors2; the present paper gives further details on the graphitization and precipitation-hardening effects only. After the completion of this work a paper by L. Lykkin3 appeared, confirming the authors' conclusions regarding graphitization.

Jan 1, 1935

By J. Halpern, D. R. McKay

SOME of the most important hydrometallurgical developments in recent years relate to processes involving the oxidation of sulfide minerals in aque- ous suspension at elevated temperatures by air or oxygen under pressure. Among these is the acid pressure-leach process which has been developed, particularly for the treatment of pyritic uranium ores.1-5 In this process, an aqueous suspension of the ore is digested in an autoclave, in which an overpressure of air or oxygen is maintained, at temperatures above 100°C. Oxidation of the pyrite (FeS,)

Jan 1, 1959

Procurement of uranium is vital to the future of the Nation. Its utilization for atomic energy can destroy mankind or raise an unsurpassable civilization-the problem of the statesmen. Uranium poses a challenge to the mining profession. Evanescent in occurrence, its discovery and mining can mean substantial profits, plus safeguarding the future of the Nation.

Jan 9, 1951

By John Chipman

IT has been long known that the gas evolved during the boil in the open-hearth furnace is mainly carbon monoxide associated with smaller quantities of other gases. A number of attempts have been made to determine the precise effects of carbon and oxygen content of the bath, and of other factors, such as temperature, upon the evolution of carbon monoxide. In his investigation of the carbon-iron oxide product in liquid steel, Herty1 showed that the value of this product at equilibrium could be approximated by plotting the value of the product observed in open-hearth reactions against rate of carbon elimination, and extrapolating to zero rate. The results of this study showed a slight but definite effect of temperature upon the carbon-iron oxide reaction. Experimental studies of the evolution of gases from rimming-steel ingots have not yet attained the degree of precision necessary for an exact understanding of the effects of pouring temperature, carbon content, and iron oxide in the metal upon the composition of these gases. Klinger2 showed that the gas consists mainly of carbon monoxide, and that con-siderable variation in its composition occurs during the solidification of the ingot. In order that these variations may be understood in their proper relationship to the progress of solidification of the ingot and the segrega-tion that accompanies solidification, it is essential to have a knowledge of the condition of equilibrium in the several chemical reactions by which the gases are being formed. It is also necessary to understand the effects of temperature upon the equilibria, and further, to know the manner in which the temperature of the liquid metal within the ingot changes as the skin of the ingot is being built up. The reactions in which we will be chiefly interested are those involving in the one case the oxides of carbon, and in the other case steam and hydrogen, with iron oxide and carbon in the liquid metal. The reactions as they occur in unalloyed liquid iron, and their respective equilibrium constants are written as follows:

Jan 1, 1937

By Eifu Moriyama

In 1953, Akita Plant, having a capacity of 560 tons per month, was built at Akita city by Mitsubishi Metal Mining Co., Ltd. for the purpose of treatment of the Ikuno and Akenobe Mines's zinc concentrates. Akita city, in whose neighborhood the black ore has been discovered, is located about 500 Km north of Tokyo and faced with the Japan Sea. This plant has been continuously expanded to have the capacity of 7,500 tons per month by the end of 1969. Efforts have been made to mechanize installations and to achieve continuous process. One of the characteristics of Akita Plant is the recent establishment of the residue treatment process. Many processes had been investigated, and finally commercial sulphate roasting of the residue has been carried out since 1965. At Akita Plant, special high grade electrolytic zinc, zinc alloy for die-casting (MAK brand), cadmium, cement copper and sulphur dioxide gas are produced. Sulphur dioxide gas is sent to the next door fertilizer plant to make acid. Table 1 shows production and the average assay of the electrolytic zinc and cadmium in 1969. This plant is divided into four main sections, two subsections, and residue treatment sections: Main sections are: (M-1) roasting section, (M-2) leaching and purification section, (M-3) electrolysis section, (M-4) melting and casting section,

Jan 1, 1970

By J. C. Jaeger

The study of brittle fracture of rocks has been a much neglected subject until quite recently and now is in a state of transition and rapid development. Historically, three methods of testing were used by engineers: uniaxial tension, bending, and, by far the most common, uniaxial compression of cubes. This latter was probably adequate for engineering requirements, but from the last century onwards there has been a demand from geologists for a study of the properties of materials under conditions comparable with those at depth in the earth's crust. King1 remarked that "in engineering practice a cube of the material is put into a testing machine and the stress required to crush the cube is measured. This gives the limiting stress difference for the material so long as the boundary conditions are similar to those existing during the test . . . this may by no means be the case when the boundary conditions are very different from those existing in the test, for instance, in the case of rupture in the neighbourhood of a cavity. . . ." Despite this very clear statement of principle, many writers until recently (e.g. Jeffreys2 used the uniaxial compressive strength as a measure of the 'strength' of rock. In the last century (Becker 3, it was both conjectured and, for some rocks, known qualitatively, that plastic deformation could occur under confining pres- sure; the demand from geologists has been for the study of flow rather than fracture of rocks.. From the time of von Karman (1911) and Böker5 (1915) onwards, apparatus has been built which could provide confining pressures sufficient to make some rocks plastic. Many experiments tended to be made on rocks such as marble, which readily become plastic, and the general tendency was to make relatively few experiments in the brittle range. This is particularly true of many experiments on combined stresses. As a result of this, there is not sufficient data to provide adequate information

Jan 1, 1967

By Frederick J. McGarry, Parviz F. Rad

Although tunneling machines have attained very high advance rates in medium-hard rocks, the need for frequent repairs has slowed their use in very hard rocks. Laser- assisted tunneling is expected to improve tunneling machine performance by improving either specific energy or amount and quality of muck. The beneficial effects of lasing are the initiation and growth of microcracks from differential thermal expansion of grains, and overall spalling in the vicinity of the lased area. Using a constant thrust rock cutting device with disk cutters, the effects of cutter geometry, cutter diameter, thrust, and speed variations on specific energy and muck were explored and the improvement in performance of disk cutters caused by lasing was evaluated. It was found that the improvement depends on beam power and density, beam speed, pattern of heating, and cutting pattern and procedure. A focused beam slightly offset from the cutter path gives the most improvement both when cutting on a smooth surface and when cutting in previously cut grooves.

Jan 1, 1971

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

Jan 1, 1952