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By Roy P. Full, Robert M. Grantham

Regional structural adjustments in early Tertiary time resulted in the development of the Republic graben, a major down-dropped block that is from 6 to 10 miles in width and more than fifty miles in length. The graben became the center of extensive volcanic activity during Eocene and Oligocene time, resulting in a thick sequence of water-laid tuffaceous sediments, volcanic flows, and associated intrusives. A younger series of sediments, pyroclastics, and flows were deposited in structural depressions within the graben following the period of widespread volcanic activity. The Republic mining district is located along one of the major intragraben structural zones, where continuing subsidence during the period of volcanic activity resulted in an increased thickness of flows and associated flow breccias and pyroclastics. Intrusive masses in part healed early graben-forming faults, but later subsidence reopened old faults and created new fracture zones which later became the control for the gold-quartz veins. Considerable block adjustment along the subsidence area is evidenced by the structural pattern in the mines, and telescoped vein structures indicate north-south compressional stresses and east-west graben-forming tensional stresses prior to and during the emplacement of the veins. The veins, varying from a few feet to more than 50 feet in width, are filled primarily by fine-grained quartz, commonly chalcedonic or porcelain-like in appearance. Finely laminated dark-gray to black concentric banding within the veins generally distinguishes the better-grade ore zones, which contain finely disseminated sulfides and ore minerals that include principally electrum, stephanite, naumannite, and native silver.

Jan 1, 1968

By Rossiter W. Raymond

(Chattanooga Meeting, October, INS.) THE formal outline of Mr. Hague's life and work is embraced in the following statement, chiefly based upon data furnished by him, at my request, shortly before his death. At that time the probability that I would survive to record his death was apparently small; but I urged upon him the duty of providing, whether for me or for my successor as Secretary of the Institute, trustworthy material for the notice which somebody would some day have to write-and which might otherwise be incomplete or incorrect. Mr. Hague, with characteristic promptness and freedom from affectation, did what I asked of him; and I am therefore . able to present an authoritative sketch-concerning the details of which I shall add my own comments, and some particulars obtained from others of his personal friends. James Duncan Hague was born Feb..24, 1836, at Boston, Mass., where his father, Rev. William Hague, D.D., an eminent clergyman, then resided. After a preliminary, education in private. schools, be studied in 1854 at the, Lawrence Scientific School of Harvard University; in 1855 and 1856 at the University of Göttingen, Hanover; and from 1856 to 1858 at the Royal Mining Academy of Freiberg, Saxony. In 1859-1861 he was attached as chemist to a South Sea exploring expedition, sent by W. H. Webb, of New York, to examine Jarvis, Baker, and other islands for phosphate-deposits. After the outbreak of the Civil War, he entered the U. S. Navy, serving for a year as Judge Advocate to the fleet stationed at Port Royal, S. C. In 1863 he became Superintendent of the Albany and Boston copper-mine, in the Lake Superior region, where he was also connected with the earliest development of the Calumet and Hecla property. In 1867 he became the First Assistant Geologist in Clarence King's famous Exploration of

Feb 1, 1909

By J. E. Lamar

THAT Illinois is an important mineral producing state is well known. A value of over $237,000,000 for the mineral products in 1926 indicates the magnitude of the industries. Coal mining is the largest mineral industry, and the value of its product was about 63 per cent of the total mineral production of the state. Oil and gas constituted about 8 per cent and the non-metallic minerals about 29 per cent. This 29 per cent represents the production of a varied group of mineral industries of wide geographic distribution through the state.

Jan 1, 1929

By D. Harrington

ONE of the main functions of the United States Bureau of Mines is to obtain and disseminate information that will promote safety in and around mines, and the health and safety of employees engaged in mining. Serious health and safety conditions arising out' of contamination of air in metal mines by dust, fumes from explosives and fires, and absorption of oxygen by timber and other causes, led the Bureau of Mines to cooperate with the United States Public Health Service in the study of dust occurrence and ventilation in metal mines in various parts of the country. Dr. A. J. Lanza, of the U. S. Public Health Service, and Edwin Higgins, mining engineer of the U. S. Bureau of Mines, in 1915, made a detailed study in the mines around Joplin, Mo., their reports1 are now available. In 1916, 1917, and 1918, a similar study was made in the Butte, Mont., region by Doctor Lanza and D. Harrington, mining engineer of the Bureau of Mines; the reports of this investigation will be available soon. In 1919, the study was continued in some of the Arizona mines by D. Harrington, of the Bureau of Mines, and G. E. McElroy and Dr. R. A. Koronski, of the U. S. Public Health Service, the underground work being completed in June, 1920; these reports are now being prepared for publication. In the spring of 1920, the scope of the work was extended, with D. Harrington in charge as supervising mining engineer, and short studies made in the mines of the Coeur d' Alenes in Idaho and around Oatman, Ariz. It is hoped soon to extend the work into mines of California, Nevada, Colorado, Michigan, and Minnesota, and ultimately to other states should the mining companies be willing to cooperate.

Jan 2, 1921

By D. Mills, G. B. Craig

ZIRCONIUM has been float-zone-refined in an electron-beam furnace and the redistribution of oxygen, iron, and tungsten has been measured. The iodide zirconium used in the present experiments initially contained both oxygen and iron in the range 100 to 200 ppm by weight, and tungsten in amounts less than 10 ppm. Float-zone refining of zirconium, using induction heating, has previously been attempted by Kneip and Betterton1 and Langeron.2 Kneip and Betterton were primarily interested in the removal of iron and nickel. They achieved some purification, with respect to both these elements, in material given up to six passes at 150 mm per hr under an argon atmosphere. Langeron reported purification for a large number of elements after four completed passes in a static vacuum system operating at pressures less than 10-6 mm of Hg and with rates of zone travel between 30 and 40 mm per hr. He did not report oxygen concentrations, but stated that there was inverse segregation of this element. westlake5 has also used a minimum of four zone passes to remove iron from zirconium. No rates or conditions were given. Belk6 has shown that tungsten contamination can occur during electron-beam melting. He reported an increase from 0.01 to 0.05 pct by weight tungsten in molybdenum after four complete zone passes. The vacuum system for the electron-beam unit used in the present investigation consisted of a single-stage rotary pump backing a liquid-air-trapped oil-diffusion pump. A pressure of less than 10-8 mm of Hg was obtained with Dow-Corning 705 fluid in the diffusion pump. In order to avoid contamination of the zirconium by evaporation from the tungsten filament, a special focusing cage4 was employed. Three rates of zone travel, 114, 38, and 4 mm per hr, were investigated, with the liquid zone moving from the bottom to the top of the bar. The bars used were 3 mm diam and the total melted length was 130 mm. Oxygen was analyzed by neutron-activation analysis using a neutron flux of 10' neutrons per sq cm per sec to form the isotope N16 by the 016 (n,p) N16 reaction. The standard deviation is quoted for each oxygen determination. The iron and tungsten analyses were performed spectrographically, and the precision is estimated to be ±6 pct. Analyses for tungsten were all below the detectable limit of 10 ppm, confirming the protection given by the focusing cage. No significant redistribution of oxygen was found at the two higher rates of zone travel. The redistribution of oxygen and iron obtained after five passes at a rate of zone travel of 4 mm per hr (1.1 x 10-4 cm per sec) is recorded in Tables I and 11. Burris, Stockman, and Dillon3 have estimated the distribution of solutes during multipass zone refining. Using their curves for an effective distribution coefficient of Keff = 1.5 and 2 for oxygen and Keff = 0.3 for iron, the expected concentrations were estimated for the present material. These are shown in Tables I and 11, along with the experimentally measured values. The calculated concentrations are based on a molten-zone length of 10 pct of the total melted length, whereas in the present experiments the molten zone was approximately 5 pct of the total melted length. The effect of zone length on solute redistribution is most pronounced after a large number of zone passes. Comparison with Pfann's published data8 for solute redistribution for various Keff's and zone lengths indicates only small differences at low numbers of completed zone passes. It is evident that the expected distribution has not been realized in the case of iron. Scrapings of material deposited on the inner surfaces of the electron-focusing cage were found to be magnetic. It is, therefore, concluded that redistribution of iron is masked by evaporation. Deposition of iron inside the focusing cage was observed at all rates of zone travel. The results of the investigation may be summarized as follows: 1) Segregation of oxygen is typical for a solute with a distribution coefficient, Keff > 1. 2) No redistribution of oxygen takes place at high rates of zone travel. 3) The distribution coefficient for oxygen lies between 1.5 and 2.0. 4) Purification with respect to iron occurs mainly by evaporation. 5) The focusing cage is effective in preventing tungsten contamination.

Jan 1, 1967

By George A. Laird

I. INTRODUCTION. THIS old and once famous district played, through its enormous production of silver and gold, an important part in the history of the State of San Luis Potosi. According to a pamphlet prepared under the direction of the Governor of the State, Sr. Don Blas Escontria, and presented to the visiting members of the Institute during the Mexican meeting of 1901, this district is situated 20 km. east of the city of San Luis Potosi, in a range of mountains of moderate height, extending 135 km. N. and S., and 16 km. E. and W.; and the mineralized area hitherto developed is about 600,000 sq. m. The history of the district,. as given by the record dated 1778, and formerly kept in the San Francisco convent, says that it was discovered in 1575 by Sr. Don Pedro Irarte, and adds that the city of San Luis Rey de Francisco del Potosi received its name (in allusion to the famous Potosi mines in Bolivia) by reason of the remarkable productiveness of its gold- and silver-mines in the first period of their exploration, during which they paid to the Crown, as " quintos " (the fifth part of the product), $97,000,000, as appears from the accounts of the royal treasury. The amount of the quientos paid during the " bonanza period " of 80 years was $72,000,000. The larger sum first mentioned probably represents a longer series of years. But either will suffice to indicate the great wealth of the mines. In 1663, the decadence of the industry began with the caving¬ in of several mines, concerning which the record of 1778, al¬ready cited, says, in substance, that on Good Friday one of the owners in the enterprise, in view of the unfavorable prospect of a lawsuit in which he was engaged, set fire to the timbers supporting the underground galleries and workings of the San

Jan 1, 1905

By L. L. Brundred

The major portion of the production of the Gulf Coast area, represented by South Texas and South Louisiana, comes from the flanks of well-defined salt domes. This oil, containing an excellent lubricating stock, ranges from 17° to 28° Be. gravity. Some lighter oil is encountered but the life of such fields is, in general, an open question. In fact, there are few light-gravity fields which have proved of much value. In all of the fields water encroachment, or, more properly, water produced with the oil, is a vital factor. After the first head of high-pressure gas is removed, ever-increasing percentages of water appear, and naturally the life of the wells is materially affected thereby. The sands are, as a rule, extremely fine, very soft, and must be carefully excluded from the hole by the use of fine screen to prevent sanding up. All sands are tipped at such extreme angles as to make coring essential for the location of water strata, oil-bearing sands and important shale. beds. Even with modern coring, the correlation of logs is a difficult problem. Due to the fact that the bulk of the oil is refined for its lubricating properties, little attention has been paid to losses by evaporation in the field. This is largely influenced by the fact that the major companies have set a price schedule, showing but two grades, "A" and "B." The average oil company, therefore, does not attempt to use the gas-lift but relies primarily on the air-lift and then only on wells considered to be particularly adapted to its use, namely those capable of producing large quantities of fluid and yet not having sufficient "kick" to flow. Furthermore, as the gas contained in the reservoirs is mostly ricthane such gas being very quickly vaporized and produced in large quantity in the early life of the fields, there is little gas left after the first flush flowing period of the wells. In fact, it is very generally conceded that gas is a precarious fuel to depend on in any of the coastal fields. This situation largely accounts for the fact that air, as the lifting medium, is almost universally used. In the average field, wells are drilled on the flanks of the domes in close proximity to one another, largely on account of the extreme dips of the formation and "town lot" leases, and space to set up machinery and

Jan 1, 1928

By William Paxton Hewitt

The San Carlos lead deposit in northeast Chihuahua yielded approximately one million tons of galena ore from a blanket-like deposit. Countryrock, composed of Cretaceous limestones and calcareous shales as old as late Albian-early Aptian, and an underlying undated quartzite series, has been warped into a northwest trending anticline and has been invaded by a light-colored holocrystalline igneous rock. Magnetite and contact metamorphic minerals heterogeneously mixed with variable amounts of pyrite, sphalerite and galena, are concentrated along the anticlinal axis where they replaced magnesia-rich argillaceous sediments above the quartzite contact. Magnetite and associated silicates were deposited under near-contact conditions. Following a period of post-magnetite shattering, pyrite, sphalerite and galena were introduced at lower temperatures. Galena and associated dolomite or magnesite, the final phase of mineralization, are concentrated at the top of the deposit near the anticlinal crest and extend upward into isoclinally folded dolomitic argillites. INTRODUCTION AND ACKNOWLEDGEMENTS The stoped outlines of the San Carlos Mine are a pattern for a stratiform blanket-like deposit. But the close association of mineralization with an anticlinal axis, an observed relation between high grade galena mineralization and the apices of isoclinal folds, and the petrographic story of mineralization introduced into shattered areas make the deposit an example of structural control of ore de-

Jan 1, 1970

By H. A. Guess

AT the outset, said Mr. Guess, I may say that although I believe the present engineering courses in the various colleges and universities could be arranged to give the student within the same time limit a broader general education of un- doubted value, still I do not agree with the view held by many that engineers in comparison with those of other occupations-let us say doctors, lawyers, bankers, and so-called business men-seldom arrive at high executive positions. After all, we must remember that engineers are not very numerous as compared with the occupations just mentioned and therefore a lesser number reaching high executive positions stated numerically might be a larger number stated as a percentage. We all know there must be throughout the United States say three doctors to one engineer, but I don't think that even numerically there are as many doctors in high executive positions as engineers, and it is a fortunate thing for the country that doctors as a class are so busily engaged in alleviating sickness and suffering and in the advancement of medical science that they do not aim particularly for high executive positions.

Jan 1, 1926

By Henry S. Rawdon

Any laboratory corrosion test, as judged from the practical point of view, is valuable only to the extent that it foretells what will, in all probability, occur in service. Such a test is most properly to be considered as a "pilot test," that is, a test which indicates the direction along which action may be expected to occur rather than as a truly quantitative test which would be expected to tell just how and to what extent the action would proceed. It is generally recognized that laboratory corrosion tests should be chosen with particular reference to the character of service expected for any particular type of metal, so far as it can be foreseen. Even when this requirement has been fulfilled, however, the question whether the actual service behavior of the material is in accordance and general agreement with predictions based upon such laboratory tests is always a pertinent one. The information available in the technical literature bearing on the correlation between the service behavior of metals from the corrosion standpoint, and the results obtained with the same metals in laboratory corrosion tests is very meager, indeed. The results which have been obtained in weather-exposure tests of sheet duralumin which form the body of this discussion are presented here for their bearing on this particular phase of the problem of the corrosion resistance of duralumin. Although the exposure tests described have not been completed, in the sense that all of the tests, in the series initially laid down, have been accomplished, still the general trend shown by the results is so clear that a number of definite conclusions at this stage (subject, of course, to possible modification in the light of later results) are believed to be warranted. The tests reported upon here form one phase of the much broader study of this subject which has been under way for several years in which the National Advisory Committee for Aeronautics, the Bureau of Aeronautics of the Navy Department, the Army Air Corps and the Bureau of Standards have cooperated. Without the very helpful cooperation of the manufacturers in furnishing the

Jan 1, 1929

By Henry S. Rawdon

Any laboratory corrosion test, as judged from the practical point of view, is valuable only to the extent that it foretells what will, in all probability, occur in service. Such a test is most properly to be considered as a "pilot test," that is, a test which indicates the direction along which action may be expected to occur rather than as a truly quantitative test which would be expected to tell just how and to what extent the action would proceed. It is generally recognized that laboratory corrosion tests should be chosen with particular reference to the character of service expected for any particular type of metal, so far as it can be foreseen. Even when this requirement has been fulfilled, however, the question whether the actual service behavior of the material is in accordance and general agreement with predictions based upon such laboratory tests is always a pertinent one. The information available in the technical literature bearing on the correlation between the service behavior of metals from the corrosion standpoint, and the results obtained with the same metals in laboratory corrosion tests is very meager, indeed. The results which have been obtained in weather-exposure tests of sheet duralumin which form the body of this discussion are presented here for their bearing on this particular phase of the problem of the corrosion resistance of duralumin. Although the exposure tests described have not been completed, in the sense that all of the tests, in the series initially laid down, have been accomplished, still the general trend shown by the results is so clear that a number of definite conclusions at this stage (subject, of course, to possible modification in the light of later results) are believed to be warranted. The tests reported upon here form one phase of the much broader study of this subject which has been under way for several years in which the National Advisory Committee for Aeronautics, the Bureau of Aeronautics of the Navy Department, the Army Air Corps and the Bureau of Standards have cooperated. Without the very helpful cooperation of the manufacturers in furnishing the

Jan 1, 1929

By William O. Hotchkiss

IN COMMON with every other good citizen I long for conditions that will make perpetual peace a reality throughout the world. I have studied the statements of our public men relating to what we must do to bring this about after this war is over. In most of these I find one common error. They always build their plans on the unstated, subconsciously accepted premise that there can be such a thing as an ideal nation whose citizens are possessed of infinite wisdom and actuated only by motives that are above reproach. This heavenly vision fails to correspond with the facts. We wish it could be true but we are forced sadly to admit that the human beings that will live here after this war is over are going to be much like the fallible race that has occupied our planet for the past centuries.

Jan 1, 1943

AS provided in Article VIII, Section 4 of the By- laws, the Papers and Publications Committee has formulated the following, rules of pro-cedure and submitted them to the Board of Directors for consideration and approval. In preparing these rules the committee, and an active subcommittee con-sisting of Messrs. Norris, Sharpless; Fohs and Wither-ell, have kept in mind the desirability of codifying the practice that has grown up through the now sev-eral years of experience of the committtee, without casting them in a mold so rigid as to be hampering. The problems of the Institute change from year to year and the methods of publication must change also to meet each new situation as it arises. "The estab-lishment of divisions and special volumes devoted to the papers. read before each required certain changes from former practice. These rules have been framed with this in view. The committee suggested, however, in its letter of transmittal, that the system will be made all the more workable if the Board will, as far as practicable, in making appointments to this committee, arrange for representation from each of the professional divisions and technical committees. It is understood that the chairman of the committee will be named by the Board. The rules regarding spe-cial volumes have been framed, keeping in mind the present policy of distribution, as already approved by the Directors under which the special volumes go only to the special. groups except on request. The committee has not attempted to provide rules governing consideration of any appeal made to the Board from one of its decisions, but its services and files will necessarily be at the full service of the Board in any such event. The rules which were ap-proved by the Board at its meeting on March 30, 1928, are as follows: Signed by C. S. Witherell, Chairman. (A) The authority of. the Committee on Papers and Pub-lications, hereinafter called the Committee, is defined in Art. VIII, Sec. 4 of the By-laws of the Institute, which reads as follows: "Papers and Publications: The Committee on Papers and Publications shall consist of the Secretary of the Institute, and at least twelve members of the Institute, to assist in passing on all papers offered for publication. They shall be appointed annually by the Board of Direc-tors, on recommendation of the President, and shall have authority, subject to appeal to the Board, to accept or reject papers for publication in the Transactions and Technical Publications of the Institute. The Commit-tee shall formulate a set of rules of procedure which, when approved by the Board, shall have the force of By-laws until revoked or amended." The policy of the Committee will be to uphold the ob-jects of -the Institute as set forth in the Constitution (Arti-cle 1, Sec. 2).

Jan 5, 1928

By E. G. Dean

A method of top slicing has been devised at the Miami Copper Co.'s mine at Miami, Aria., which differs radically in some ways from the customary methods of top slicing. The area of that section of the orebody in which top slicing is used is about 800 ft. square. The ore, while for the most part soft, is, nevertheless, considerably harder than the capping. The latter is siliceous, seldom containing any clay or other binding material, and breaks into fine particles so that it runs like sand if given the opportunity. Because of these facts, and because the ore is above the average grade of the mine ore, it has been mined by top slicing. Haulage levels are opened up 150 ft. apart, vertically, with two sub-levels between at 50-ft. intervals, to facilitate the putting up of ore chutes. These sublevels are used during slicing for distributing air in the ventilation system. On the haulage level the drifts are spaced on 50-ft. centers, and raises along these drifts are also spaced on 50-ft. centers, except the incline raises as hereafter noted. The raises are cribbed where necessary. Where the wear will be excessive, 1/4-in. iron plates are spiked to the top of every third set of cribbing, for its protection. When top slicing was first used, an attempt was made to carry a slicing face from fifty to several hundred feet long. Timber and other supplies were brought in through long drifts from an auxiliary shaft. Great difficulty was experienced in keeping these drifts open, the side pressure breaking the posts and the top weight breaking both caps and posts. Furthermore, the men could not work efficiently while these drifts were being repaired. The slicing faces advanced irregularly, due to varying conditions, and in many ways the results were not all that could be desired. It was then decided to divide the slicing area into blocks 200 ft. square and this was later changed to 250 ft. square. At the center of each block a two-compartment raise is put up as a supply raise, the compartments being 2 ft. 6 in. and 4 ft. by 4 ft. 4 in., the smaller being used as a manway. Station sets of 12 by 12 timber with

Jan 1, 1917

By J. B. Reed, T. A. Read, H. Rosenthal

Although the season cracking of brass has been a subject of experimental investigation for more than thirty years, the mechanism that is responsible for this phenomenon is still obscure. While at- tempts to elucidate the stress-corrosion cracking of some alloys have been relatively successful, the principal accomplishments made in the studies of the season cracking of brass have consisted of improved techniques for the fabrication of articles of alpha brass, which reduce the danger of season-cracking failure in service. The primary purpose of the present paper is to collect the published experimental data which appear to be of importance to the development of an adequate theory of the mechanism of the season cracking of brass. Some of the possible mechanisms which have been proposed will also be discussed, together with some promising avenues of future attack on the problems. Several excellent survey papers on season cracking are available, including the recent ones by Croft and Sachs(1)2 and by Gibbs(2). The principal facts concerning season cracking, as presented in these papers, may be summarized as follows. The season cracking of alpha brass is a special type of stress-corrosion failure, which may occur in atmospheres containing ammonia, air, and water vapor. The stress causing failure may be either the

Jan 1, 1945

By Chikao Nishiwaki

INTRODUCTION The Japanese dependency for mineral raw materials from foreign sources increased rapidly within the 20 years since the Korean war. During this 20 year period Japan has attempted to industrialize and develop her economy while depending mostly on heavy import of nearly all kinds of mineral raw materials. She has fabricated them using energy generated mostly by mineral fuel that are also imported. Fabricated goods are either used domestically to accelerate more fabrication industry or exported after adding more refinement or fabrication. In this paper iron ore as a major raw material for the Iron and Steel industry, three major base metals, copper, zinc and lead, and petroleum as a major energy source have been selected as examples to represent the general features of various kinds of mineral raw materials that are imported. Among other important mineral commodities for which Japan dependa upon foreign sources are: Aluminium, nickel and cobalt, potash and phosphorous 100 percent dependent and tin, tungusten, chromium and molybdenum over 95 percent dependent. IRON ORE Statistics for the important iron and steel raw materials, namely iron ore, coal and scrap iron are shown in Tables 1, 2 and Fig. 1. Iron ore is by far the most important and basic among these three commodities. There has been practically no steel or iron imported as a metal into Japan during this period. Iron ore, including aggregate such as pellets, and metallurgical coal are mostly transported in large ore cargo boats to the port where very efficient port facilities unload them directly at the steel mill site. As a result

Jan 1, 1976

As knowledgeable men in the industry know, a mineral occurrence is found through prospecting but an ore deposit is "made" -made through, first, imaginative and effective exploration; thence through efficient engineering, sales and management. There are two main phases of exploration-reconnaissance and target investigation-each of which can be further divided into two additional stages (see accompanying table). The search for a new ore deposit within a known and geologically mapped mining district involves only the last two stages, whereas the search for a new orebody in a virgin geologic environment involves at least three stages and often the full sequence. Of course, some of the exploration stages may be bypassed depending on available results of previous mineral surveys and/or exploration by individuals, business concerns, and governments.

Jan 10, 1967

By Arthur Notman

TO present some idea of the magnitude of the gold-mining industry of Canada and the world, the records of 106 gold-mining companies currently paying dividends have been studied. Forty of these are in Canada, and 37 on the Rand in South Africa, these being all the straight gold-mining companies that paid dividends in the two areas in 1938. None of the base-metal companies that produce gold as a by- product, or even as a major fraction of the value of their total product, have beezl included. In addition, a group of 29 similar companies from Southern Rhodesia and the Gold Coast in Africa, India, Australia, Manchuria, Philippine Islands, the

Jan 1, 1939

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

By Victor R. Cabrera

Expansion of Marcona Mining Co.'s operations in Peru several years ago increased the number of laborors and the variety of required jobs at the Company's facilities. This change made the former wage administration outdated, becoming evident by the increase of inequity grievances which threatened tile Company's good labor relations. Such a situation led Marcona to design a new wage plan based on a thorough job evaluation of all its laborer positions. The iron ore deposits, 15 miles inland from the ports of San Juan and San Nicolas, Peru, supply ore to steelmakers in the U.S., Europe and Japan. Marcona Mining Co. operates the mines under a long-term lease agreement with Peru.

Jan 7, 1964