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By Evan Just

THE high standards of living and improved national security that industrialization can bring are so evident that no country can be named that does not cherish the hope of industrializing. With such a universal aim, why do many countries unable to develop their own industries accomplish so little toward attracting the foreign private investor, who alone can provide them with the necessary capital and skill? Obviously, because they fail to under- stand what constitutes a favorable climate for investment, because they have false notions about being exploited or dominated by the foreign investor, or because they are so nationalistic they refuse to permit outside assistance. The purpose of this paper is to aid the citizens and policy makers of developing countries in achieving their aims, by defining the conditions which en- courage investment and portraying the results of a policy of encouragement. The following is quoted from Eugene R. Black, president of the World Bank:

Jan 6, 1957

By Hon. Abrams S. Hewitt

Gentlemen : If my first words were other than those of thanks for the high honor of being called to preside over the American Institute of Mining Engineers, I should do injustice alike to you and to my own sense of the obligation, under which I have been placed by your voluntary choice. When the position was first suggested to me, I resolutely declined to allow the use of my name, on the ground that, by training and occopation, I was not entitled to this honor, which, it then seemed to me, should be conferred only on a professional engineer. In fact, the history of the Institute, which had honored itself, as well as my distinguished predecessors, David Thomas, Rossiter W. Raymond, and Alexander L. Holley, by elevating then] to its highest office, seemed to indicate the line and the limit of safe precedent, in which I did not then see how I could be included. But my scruples were finally removed by the consideration that, as in the course of human industry, the pioneer, of whom Mr. Thomas was so marked a type, must precede the mining engineer, so fitly personified in Dr. Raymond, and be followed by the mechanical engineer, whose incarnation we behold in Mr. Holley; so all these must be supplemented by the man of affairs and finance, in order that "enterprises of great pith and moment" may be prosecuted to a successful issue. I felt, therefore, that I had no longer any right to resist your preference, or to deprive myself of what I must regard as the crowning honor of an active career. On an occasion like the present it seems appropriate to review the history in this country, during the last hundred years, of those industries which the Institute of Mining Engineers specially represents. There is much in the story with which other members of this body are more familiarly acquainted than myself; yet I fancy that to all of them, and not less to our distinguished and most heartily welcome gnests from abroad, a comprehensive outline of the progress of mining and metallurgy in the United States mill prove interesting. I ask your attention, therefore, to a condensed account of that subject, embracing a statement of the beginnings of the industry on our shores, of the notable events attending its increase, and of its present

By Stanley D. Michaelson

Stanley D. Michaelson retired in 1976 as chief engineer, Metal Mining Div. and director of the Engineering Center for Kennecott Copper Corp. An active consultant on mining and metallurgical assignments, Mr. Michaelson is also currently adjunct professor of mining engineering at the University of Utah. He received his B.S. degree in mining engineering from Lehigh University in 1934 and an honorary E.M. degree from the Montana School of Mines in 1961. Mr. Michaelson received AIME's Robert H. Richards Award in 1962 and was named a Distinguished Member of the Society of Mining Engineers of AIME in 1975. He has served as a Director and as a Vice-President on the AIME Board of Directors and is a Past President of the Society of Mining Engineers. He became an Honorary Member of AIME in 1978.

Jan 1, 1979

By Charles Fulton

EXPERIMENTAL work on the process was begun on a laboratory scale at Cleveland, Ohio, in 1914, and transferred to East St. Louis, Ill. in 1916, where a commercial sized furnace was in technical operation until January, 1918. The essential steps of the process are as follows: Oxidized zinc ore or roasted zinc concentrate is mixed with crushed coke and coal-tar pitch and formed into briquets 9.25 in. (23.5 cm.) in diameter and 21 in. (53 cm.) long in a manner similar to that used in the manufacture of graphite or carbon electrodes, except that much less care and time are required. The composition varies with the nature of the ore; in one case, the composition was 100 parts ore, 70 parts coke, and 18 to 20 parts pitch. These briquets maintain their form and volume during and after the distillation of the zinc. This object is gained by using coke as the matrix and coal-tar pitch as the binder; this pitch becomes coke on heating and unites the ore particle and the original coke particle into a continuous mass. The briquet is an electrical conductor but only to such, a degree that it can be used as a resistor. The size of the ore, as in the present practice of zinc metallurgy, ranges from fine material, such as flotation concentrate, to coarse table and fine jig concentrate. The process is not restricted to any particular kind of ore, but is applicable to pure high-grade ores, ores high in iron, and complex zinc lead ores, since the residue from the distillation is held immovably in place within the briquet. In the case of complex zinc-lead ores, the distillation is conducted with a carefully regulated temperature so that a high percentage of lead is retained in the distilled briquet, which may then be smelted for its lead content. In present zinc smelting practice, the reduction fuel is from 40 to 50 per cent. of the weight of the ore. In the briquet, it is from 60 to 85 per cent. of the ore; but unless the ore is exceptionally high in residue, the distilled briquet

Jan 9, 1919

By Thomas S. Blair

I FEEL a certain sense of responsibility in bringing before you the subject of the direct process in iron manufacture. I am aware that, in such a body as I have now the honor of addressing, there are few who are not already so well informed upon its past history that it would be a weariness to them to listen to anything else than an account of practical success. Yet, to claim that success involves so much that, if I do not make good my claim, I deservedly expose myself to severe criticism. The whole literature of the art, so far as it relates to the direct process, is, up to this time, but a history of failure. It is safe to say that more money, time, and talent have been fruitlessly spent in the pursuit of this object than in all the other unsuccessful efforts in the whole line of iron metallurgy. A distinguished authority in patent law has remarked that " the invention records of the United States and of foreign countries are filled with the waifs and abandoned relics of these abortive struggles." Dr. Percy, whose great work may be taken as an epitome of all that was worth mention, whether useful or curious, in pig-iron metallurgy, up to the date of its publication (1864), after giving elaborate accounts of various attempts at the direct process, condenses his own opinion of all that had been then effected, into a brief but summary comment upon a pamphlet of one of the sanguine inventors who had said: "It is evident that the present mode of working iron

Jan 1, 1874

By S. B. Christy

Jan 1, 1902

By E. A. Reilly, G. R. Gardner, F. P. Lasseter

THE methods that may be applied to the treatment of slurries and water, as these are related to practical coal-preparation problems, are concerned essentially with the movements of solids suspended in water. It is assumed that there are no fundamental differences between the principles involved in the treatment of coal slurries and the phenomena encountered in general mineral-dressing practice, and the latter are presented in some detail. Basic principles are correlated with present practice for both the anthracite and the bituminous coal. fields, and meth¬ods are discussed which are designed to utilize best all the material subjected to treatment and suggest a sound approach to the solution of problems relating to the return of clear water to process or to streams. In order to approach the practical phases of the subject with sufficient understanding of the basic principles, it is necessary to discuss two types of phenomena that are applicable. The first is flocculation and the second is sedimentation. Descriptive matter is given covering the various meth¬ods and types of equipment employed to conduct these operations, with emphasis on their application to water and coal-slurry treatment.

Jan 1, 1943

By C. Richards Honeycutt, Frederick C. Langenberg, Guenter Pestel

Solidification in a moving electromagnetic field was successful in altering the as-cast grain structure of steel ingots. The equipment is described and exerimental results are presented for several different alloys. Conditions for optimum grain refinement are described and an empirical design constant presented. The effect of the grain refinement on hot workability is briefly discussed. T HE grain structure of a steel ingot teemed into a metal mold can be defined by macroscopic examination in semiquantitative terms. For example, the relative volume of obviously differing structures can be estimated with the classic definitions of chill, columnar, and equiaxed zones. Experimental evidence has proven that the grain structure of an ingot is affected by changes in such factors as teeming temperature, rate of teeming, degree of turbulence, size of ingot, mold characteristics (including preheat temperature, design and coating), and composition of the metal (especially as it affects the range of solidification). Significant advances have been made in fundamental solidification studies; but the principles which have been developed are difficult to apply tothe complex and changing phenomena that occur simultaneously during ingot solidification. In particular, many attempts have been made to refine the as-cast structure of ingots, with special emphasis on the columnar grains. The formation of large columnar grains is generally considered harmful to the further fabrication of an ingot. It may also result in undesired ani-sotropic properties. However, columnar grains are not undesirable in all grades, or product applications, and caution must be exercised to determine in which grades and applications columnar grains are not desired in the ingot. Although the literature on the refinement of as-cast ingot grain structures is too vast in general to review here, it is noteworthy that such methods are additions of artificial nuclei, mold vibration, mechanical stirring or ultrasonic agitation of the molten metal, and controlled cooling and reheating during solidification have been tried with varying degrees of success. However, it is doubtful that any method of refining the as-cast ingot grain structure has been completely successful on a commercial basis. The purpose of

Jan 1, 1962

By Cyril Stanley Smith, W. Earl Lindlief

A study of the mechanical properties of the alloys of copper and silver led to the discovery that the solubility of silver in copper was greatly different from that generally supposed, therefore some work was done to determine the solubility with greater accuracy than had previously been achieved. After the work had been completed, two papers were published' giving solubility figures which agreed closely with one another and with the work described herein. A detailed comparison of that work with the present will be given later. Preparation of Allots The copper used in making the alloys was electrolytic ingot of high purity. The silver was prepared by precipitation as chloride from nitric acid solution, followed by fusion of the washed precipitate with sodium carbonate and potassium nitrate. This method gives metal containing at least 99.99 per cent silver. The copper was first melted under charcoal in a small electric resistance furnace and the silver added as pure silver, it being unnecessary to make any intermediate alloys. After thorough stirring the metal was poured into a mold of suitable form. The alloys contained between 0.008 and 0.015 per cent of oxygen. Small amounts of oxide were visible under the microscope, but it is not believed this would have much effect on the results. Copper-silver alloys are notorious for segregation, consequently a few experiments were carried out to find a form of casting with as little segregation as possible. A mold 6 in. long and 1/2-in. dia. was first used, and an alloy nominally containing 5 per cent silver was cast in it, while some of the same alloy was poured directly into water to obtain the maximum rate of cooling possible. Analyses were made both on this sample and on turnings from the top and bottom of the 1/2 in. dia. cast-ing, the turnings being separated into three parts according to the position

Jan 1, 1932

By R. D. Coleman, A. E. McIlhinney, C. E. Capes

tentially valuable. These losses will probably increase with the expansion of production and will require the development of effective disposal and utilization processes under pressure of the lack of adequate disposal areas, the enforcement of air and stream pollution laws, and the economic need to obtain the maximum yield of salable product.1 Fine Coal Treatment Processes Most coal cleaning methods depend upon the density difference between coal and its impurities to effect separation. These gravity concentration methods, however, are not practical for particles finer than about 100 mesh and cleaning methods dependent upon the differences in

Jan 1, 1971

PRESIDENTS DAVID THOMAS 1871 Born November 3, 1794, Cadoxtan, Glamorganshire, South Wales. Died in 1882. Attended schools in Wales. Came to America in 1839. A.I.M.E.: Member, 1871; Honorary Member. Iron manufacturer; inventor. Built first anthracite fired hot-blast furnace in America. Known as the "Father of the Lehigh Valley." President, Catasauqua and Fogelsville Railroad; Director, Lehigh Valley Railroad; Founder, Thomas Iron Co. and St. Luke's Hospital at Bethlehem, Pa.; Trustee, Lafayette College.4 ROSSITER WORTHINGTON RAYMOND 1872-1874 Born April 27, 1840, Cincinnati, Ohio. Died in 1918. Brooklyn Polytechnic Institute, 1857; Lafayette College, Ph.D., 1868; Lehigh University, LL.D., 1906; University of Pittsburgh, Hon. LL.D., 1915., Gold Medal, Institution of Mining and Metallurgy (London). A.I.M.E.: Founder, Member of 1871; Vice President, 1871, 1876-1877; Secretary, 1884-1911; Secretary Emeritus, 1911-1918; Honorary Member. Consul¬ing mining engineer; practicing lawyer, sailor, soldier, writer, orator, editor, theologian, teacher, novelist, chess player. Recognized as the "Grand Old Man of the Institute." ALEXANDER LYMAN HOLI,EY 1875 Born July 20, 1832, Lakeville, Conn. Died in 1882. Brown University, 1853; Hon. LL.D., 1878. A.I.M.E.: Member, 1871; Vice President, 1874; Manager, 1877-1879. Bessemer Medal (Iron and Steel Institute, London), posthumously. Brought bessemer process to United States. A statue was erected in Washington Square in his memory and presented to the City of New York in 1889. The inscription notes: "foremost among those whose genius and energy established in America and improved throughout the world the manufacture of bessemer steel." ABRAM STEVENS HEWITT 1876 Born July 31, 1822, Haverstraw, N. Y. Died in 1903. Columbia University, 1842; Hon. LL.D., 1887. A.I.M.E.: Member, 1871; Manager, 1872-1875. Bessemer Medalist and Honorary Member, Iron and Steel Institute (London). Gold Medal, Chamber of Commerce of New York City. Philanthropist, lawyer, statesman, publicist, pioneer in the iron and steel industry. Mayor of New York City in 1887. Business partner of Peter Cooper, Executive Manager of Board of Trustees, Cooper Union, New York City.

Jan 1, 1947

By Francis C. Frary

OF the five metals that now show the highest figures for annual tonnage production in the world, three (iron, copper, and lead) have been known and used by man for many thousands of years. The fourth (zinc) did not come into general use until the Middle Ages. Only the fifth (aluminum) is of, ultramodern origin, as far as mankind is concerned. Discovered in 1825, and first publicly exhibited at the Paris Exposition in 1855, aluminum was still so difficult to obtain that it was more expensive than silver, until the development of the dynamo provided cheap electricity and the development of the present electrolytic process for its production made it possible to make large quantities cheaply. Even today, the world production of aluminum is only about one per cent of the world production of iron, although about half that of copper by weight. The increase in production from a few tons to more than a million tons per year began with ,the development of the Hall-Héroult electrolytic process, which was first commercially operated by Mr. Hall's company, The Pittsburgh Reduction Co., in 1888. During the relatively short period of time that has elapsed since that date, it has been necessary to develop all the metallurgical and fabricating information required for the production of useful articles of the metal and its alloys, together with experience in both their production and their use, so as to be able to fit them satisfactorily into their proper places in our complex modern civilization. The fundamental properties upon which the usefulness of aluminum depends are its lightness, workability, resistance to corrosion,

Jan 1, 1953

By A Allen, J. A. Garcia

The large increase in the wages of mine workers makes it imperative that all factors tending to limit production per miner be eliminated, if possible. The trolley and storage-battery locomotive, mining machine, hoisting engine, mining system, etc., have increased the possible output per man. But this output is still limited by the capacity of the hoisting engine and cable and by the size of the mine car. The superiority of skip hoisting in metal mining is shown by its almost universal adoption. By varying the size of skip and the rope speed, any desired tonnage can be secured and, since frequently only one kind of material is handled and breakage is unimportant, the loading of the skips can be easily and cheaply effected from bins into which the cars are dumped. The cars may then be designed to fit the conditions in the mine instead of being a compromise between hoisting and mining conditions, very likely suiting neither. In coal mines, the usual practice has been to hoist the car to the surface, either on platform or self-dumping cages. Of late years the number of skip-hoisting plants in coal mines has been rapidly increasing, but there is more or less inertia to overcome in establishing so radical a change in practice; also the earlier skip operations were not uniformly successful. As a result, it became evident that metal-mining practice would require radical modification before skip hoisting could be successfully used in coal mining. Objections to Skip Hoisting Breakage Except where coal is used for coking, or for other purposes whcre breakage is unimportant, breakage of the coal is vitally important all the way from the face to the railroad car. The average selling price is seriously reduced when the percentage of screenings is increased. Following metal-mining practice exactly, the coal would be dumped into a deep pocket, cut off into a skip load by a measuring hopper or other means, dumped into a deep, narrow skip, and dropped into a bin at the top, all of which would contribute to excessive breakage.

Jan 1, 1922

By P. T. Stroup

Jan 1, 1964

By S. J. McCarroll

THE Three Kids mine, some six miles east of Henderson, Nev., is in a typical southwest desert area, with high dry summer heat and cool to cold winter seasons. The manganese deposit was located during World War I.1 During this period 15,000 to 20,000 tons of ore assaying up to 41 pct manganese were shipped. Interest in the deposit was not revived until the middle thirties, when experiments on the ore were initiated. Test work indicated possible recovery of only 70 pct by flotation, but in 1941 additional work was done at the Boulder City pilot plant of the U. S. Bureau of Mines and also by M. A. Hanna Co. As a result, the Manganese Ore Co. was formed and a plant utilizing the SO, process was constructed. Numerous operation difficulties ensued, and the plant was closed when the manganese situation in the country eased.

Jan 3, 1954

By George A. Grandy, D. W. Fuerstenau

Simulation of nonlinear grinding systems is discussed in the context of the size-discretized batch-grinding model. A linear approximation of environment-dependent (or nonlinear) selection functions is postulated for systems which exhibit feed grinding orders less than unity. For this, a convex linear combination of zero and first-order selection function forms is used to obtain an analytical solution that can be used for simulation. An example in which marked nonlinear behavior occurs is rod-mill grinding. Accordingly, a series of grinding experiments was carried out in a batch laboratory rod mill to test these techniques; agreement between experiment and the model was found to be very good. Recently, significant progress has been made in the simulation of linear grinding systems by using a population balance mathematical model. Herbst and Fuer-stenaul presented a parameter estimation scheme that can be used with the size-discretized batch-grinding model, and Gumtz and Fuerstenau3 have extended these techniques to the simulation of locked-cycle grinding. Grandy et aL." summarized the simulation of linear systems and noted important alternate solutions to the batch-grinding equation. Kelsall et a1.'-" discussed the dynamic simulation of linear batch grinding, as well as linear open and closed-circuit grinding. In all of these, the key word is linear, which certainly restricts the engineer trying to simulate a variety of grinding systems. This paper discusses an approach for the simulation of non-linear grinding systems, particularly those which exhibit grinding orders less than unity. Experimentally, dry rod-mill grinding is used to evaluate the technique presented. Batch Grinding Model The size-discretized batch-grinding model has been discussed in detail by Mika et al.'.' and by Herbst and Fuerstenau,' and therefore, will only be briefly developed here. The model is formulated by making a differential mass balance of each size fraction in such a manner that the equation parameters are precisely defined in terms of selection and breakage functions,' which can be either calculated'.' or estimated1 from experimental data. The model is phenomenological because it averages all stress-application events in the system and, therefore, does not distinguish the manner in which individual particles are stressed.' For this average environment, the resistance of all particles in a size fraction to breakage is defined by that size-frac-tion's selection function; and when fracture occurs from an average event, the breakage product size distribution is defined again by that size-fraction's breakage function. The model is deterministic and is derived in terms of a continuous time variable and a discretized size variable,' i.e., the n mass fractions associated with the n defined size intervals (see Table 1 for nomenclature).

Jan 1, 1971

By Rossiter W. Raymond

The extent to which the divining-rod is still used in this country for the detection of hidden treasure, mineral veins, or springs, is ' much greater than educated persons would be likely to suppose. For many years wells have frequently been located by its aid in New England, where the belief is widely extended among the farmers that in the hands of peculiarly gifted persons this instrument possesses special virtue. Large numbers of the oil wells of Pennsylvania

Jan 1, 1883

By S. F. Emmons

IT was said by many who discussed Professor Posepny's admirable paper on the " Genesis of Ore-Deposits," read at the Chicago meeting of the Institute, in 1893, that its most valuable feature was the clear distinction which it drew between the influence upon ore-deposits of the "vadose " circulation of waters descending directly from the surface, and that of the deep underground circulation of waters generally coming from the depths, and assumed by the author to be ascending through more or less open spaces under the influence of heat. A little later the effect of the oxidizing action of the vadose circulation upon ore-deposits was ably and exhaustively treated by Prof. R. A. F. Penrose, in a paper on " The Superficial Alteration of Ore-Deposits "f-the only one, so far as I know, which has been exclusively devoted to this important subject. My own first detailed study of ore-deposits was made at Leadville, in 1880, at a time when almost the only minerals visible in those deposits were in oxidized forms. That this form was the result of the alteration of earlier sulphides by surface-waters had to be proved at the time by induction or analogy, the general correctness of which was, however, abundantly confirmed by subsequent developments. Thus I was early impressed with the importance of distinguishing, in the study of an ore-deposit, the alteration-products, resulting from the action of oxidizing waters descending from the present surface, from the earlier-formed sulphides; and, assuming that the latter were primary or original, I called the former secondary. I also went so far as to say$ with regard to oxidized ores passing into sulphides in depth "So generally is this accepted as a rule in ore-deposits that it would require special demonstration to prove beyond a doubt that the native metals or their

Jan 1, 1902

By A. C. Stoddard

Early in the present century, prospect-ing was active in the area of the present Miami district. There were plenty of blue and green copper outcroppings, but very little ore of a grade that would stand shipping costs had been uncovered. Late in the first decade of the century, tunnels were driven into the north and south slopes of the Inspiration ridge, and two of them exposed disseminated copper sulphide ore. This was the original discovery of such ore on the ground of what eventually became the Inspiration Division of the consolidated company. By 1910 exploration of the ground area was well along and by 1911 underground development had been started. In the next few years a large tonnage of disseminated copper ore had been proven— sufficient to justify the expenditure of several million dollars in mine development and for mine equipment plus large sums for treatment plants. The mine and treatment plants were placed in production July 1, 1915. To Jan. I, 1945, there had been produced from the mines of the Inspiration Consoli-dated Copper Co., more than 106,000,000 tons of ore. Nearly all of this tonnage had been recovered by block caving. GeologIcal and EconomIc FActors Block caving is a mining system based on the fact that if a mass of rock has a sufficient number of fractures and planes of weakness the mass will disintegrate if the support of an area of sufficient size is taken away—that is, "undercut." If the material that caves away from the bottom of a block is drawn off the spalling is progressive. There is a limit to the speed of this spalling or caving action, which varies with the structure of the rock being caved. If the rock is drawn at a rate faster than the caving rate, and if this drawing is continued too long, a void may be created that could make a very dangerous condition if the area should drop as a block and force the air below the uncaved rock out through the raises and drifts. This can be a very destructive force. On the other hand, if the broken material is not drawn fast enough the swell of the material in place to broken material would pack the mass until it was almost solid again and could not be drawn without much blasting, or perhaps even partially undercutting again. Geologically therefore it would seem that any rock with seams and fractures would cave; but for block caving there should be enough seams and fractures in a limited area so that such an area will cave and produce a product that can be drawn safely, rapidly enough and at a cost justified by the value of the product being drawn. At the Inspiration the disseminated ores occur in two formations, the Pinal schist and the Schultze granite. There is no material difference in the grade of the ore formed in the schist and in the granite. The chief copper minerals are chalcocite, malachite, azurite and chrysocolla. Other copper minerals occur in limited quantity.

Jan 1, 1946

By Will H. Coghill, P. H. Delano, G. D. Coe

DATA concerning the actual net energy required for pulverizing coal are lacking from the literature on coal pulverization. Power data given in the literature concern gross power and frequently include the power expended on the air blast or product-conveyor system, as well as power lost through friction in the pulverizer itself. Consequently, such data supply no information regarding the net energy consumed in pulverizing or the relative grinding resistance of various coals. In the study of coal pulverizing much work has been done on what is known as "grindability-index numbers," but grindability tests have seldom considered the energy input (that is, the "cause" part of the system "cause and effect"). There are many records of the effect, but even these have questionable value because the "grindability" tests did not make a pulverized product by a method comparable with commercial pulverizers. In many of the tests, only a selected part of the coal was ground, and the remainder continued to be an unknown factor. Furthermore, none of the grindability tests provide the balanced circulating load common to all modern commercial pulverizing. In order to obtain better understanding of the fundamental principles of coal pulverizing, the Bureau of Mines is investigating the "cause" phase; that is, the net energy input or net power excluding friction between the moving parts of the machine. As a first step in the investigation, it was necessary to design and construct a laboratory machine in which no friction-loss corrections are involved, which could grind and finish a minus-3/4 -inch feed, which could be emptied rapidly and completely, which could operate with a continuous feed and finish in an air separator; and, most essential of all, which would be equipped with a measuring device for recording only that portion of the total power consumed in actual pulverizing, hereafter referred to as "net energy input" or "net horse-powerhours." The channel-roller pulverizer here-inafter described is believed to meet these requirements. HISTORY OF THE MACHINE The work started when Ralph W. Smith, engineer, St. Genevieve Lime Co., St. Genevieve, Mo., was appointed one of the consultants of the Bureau of Mines, United States Department of the Interior, in cooperation with the University of Alabama, to develop a machine for testing the abrasiveness of coal. Smith had already developed a machine for testing the abrasiveness of dentifrices,1 and it was thought the same principles might be applied to coal. Smith's machine had a revolving disk with an annular channel in which the sample was placed. Riding in the channel was a small block or runner of selected soft metal held

Jan 1, 1942