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By T. L. Joseph

It is a distinct privilege to participate in this meeting convened to honor the memory of Henry Marion Howe, a distinguished scientist and metallurgist. Many have added to our rapidly growing fund of metallurgical knowledge but few have made the unique contribution of formulating basic concepts essential to an over-all comprehensive view of the subject of metallography. Of those previously selected to deliver this lecture, several have added a personal touch to their discourse because they were able to refer to their associations with Dr. Howe. It was not my good fortune to know him or to enjoy his inspiring influence. Like most of you, my contact has been with his published works, which are outstanding in that they provide lucid, detailed expositions of the nature and behavior of metals and alloys. His deep understanding and clarity of expression have greatly accelerated our progress in metallography and in the use of metals. The degree to which a man's thinking, experimentation and writing contribute toward an understanding of basic laws and phenomena determines whether his life's work is of transitory or permanent value. This occasion appropriately recognizes the fundamental importance of Dr. Howe's pioneer work in the field of metallurgy.. On two former occasions, gray iron was selected as a subject for discussion. The fact that the production of pig iron has not been discussed before does not reflect any lack of interest on the part of Dr. Howe or former lecturers in the process that underlies the production of steel. Although Dr. Howe's work in his later years centered around metallography, his earlier publications show a considerable interest in the production of iron and steel. He recognized that in the ascending spiral of metallurgical advancement we are not winding a single thread but are weaving a complex fabric. Specific evidence of his interest in the production of pig iron may be found in his book' on The Metallography of Cast Iron and Steel. In explaining why blast furnaces have been in constant use for about 600 years, he says: "The process is economical because it utilizes with extraordinary completeness the calorific power of the coke due to the thorough transfer of heat from the gaseous products of combustion to the charge." This emphasis on heat transfer, overlooked in many more extended and more recent discussions of the blast-furnace process, illustrates Professor Howe's ability to see the essentials. Other distinct advantages of the blast furnace, such as the removal of- much of the sulphur and practically all of the oxygen, were mentioned. It was also stated that although the blastfurnace process is complex in nature, its outward form is comparatively simple, thus permitting large-scale production at small labor costs. All who contemplate the production of metallic iron from its ores by any other process might well consider the

Jan 1, 1947

By George W. Doffing

Numerous contradictory statements have been made in the past regarding the importance of the seasonal influence of demand for motor fuel on prices of oil securities. It has often been said that the time to buy oil securities is in the spring, or just prior to the heavy consuming season for gasoline. The fallacy of this argument is brought out in the following paragraphs. Seasonality of Oil-security Prices The indexes used in this paper as indicators of prices of oil securities and general industrials are those compiled by Standard Statistics Co. The oil producing and refining stock index includes 14 representative petroleum companies, while the all-industrials index is made up of 347 issues. All figures are stated as relatives, with 1926 = 100. The primary basis of the index, and one that gives a good weighting of the relative importance of the company within the industry, is the total market value of the stock issue outstanding; i.e., the market price times the number of shares outstanding. Adjustments are made for the addition or elimination of issues from the group index, for stock dividends, split-ups, stock rights, et cetera. At the present time the oil producing and refining index includes the following companies: Atlantic Refining Co., Consolidated Oil Corporation, Continental Oil Co., Gulf Oil Corporation, Humble Oil & Refining Co., Ohio Oil Co., Royal Dutch Co., Shell Union Oil Corporation, Socony-Vacuum Oil Co., Standard Oil Company of California, Standard Oil Co. (Indiana), Standard Oil Co. (New Jersey), Texas Corporation, Union Oil Company of California. In calculating the seasonal for oil-security prices several periods have been selected as indicat,ive of major changes in the industry, as follows: 1. 1918 through 1936. This gives an over-all picture of the industry during the motor-vehicle, motor-fuel era. 2. 1927 through 1936. This period includes the control stages, both voluntary and coercive. 3. 1927 to September, 1933. This is the pre-code period of control.

Jan 1, 1937

By F. S. White, E. L. Kinsella

THE solids fluidization process brought out by the Standard Oil Development Co. in the early forties for catalytic cracking of petroleum enabled rapid transfer of large quantities of heat from gases to solids under closely controlled temperature conditions. As the technique developed, it was natural that applications for the process outside the petroleum industry would be sought. The calcination of limestone to ' quicklime requires the transfer of a large quantity of heat at high and closely controlled temperatures. For these reasons, this possible application was one of the first to be investigated. Laboratory work conducted by the Dorr Co. indicated that lime produced by solids fluidization would be of exceptional quality. Calculation of theoretical heat balances showed that savings in fuel could be expected. Accordingly, a pilot plant of 10 tons per day capacity was erected by the New England Lime Co. at Adams, Mass., to substantiate the process. Operation of the pilot plant, previously described,1 showed that excellent lime could be produced with a saving in fuel. The work also indicated the necessity of preparing feed to remove the finer fractions if dust losses were to be held to a tolerable level. A single-stage fluidized solids drier-stripper was developed to accomplish this sizing.2 Subsequently a commercial lime reactor was erected at Adams, beginning operation in June 1949, followed by air sizer facilities completed in November 1951. This paper will describe these two applications of solids fluidization. The raw material for preparation of lime by the fluidizing process is a high calcium crystalline lime stone having the approximate chemical composition shown in Table I. The stone is first prepared by crushing and grinding in conventional equipment to pass a 6-mesh sieve. After crushing, the material is sent to the FluoDry unit for drying and dedusting. Fluidized Drying and Sizing As shown in Fig. 1, the FluoDry unit consists of a 1/4-in. cylindrical steel shell, 9-ft ID by 22-ft 6-in. overall height. Attached horizontally at the bottom is a 6-ft diam combustion chamber, approximately 7 ft 6 in. long. A refractory constriction dome, consisting of first-quality fire brick shapes, partitions the inside into two sections. The lower section is called the windbox and the upper the bed compartment. The vertical wall of the shell is lined with 6-in. first-quality rotary kiln blocks. In the bottom of the windbox a hoppered section is formed with castable refractory to permit the windbox to be readily cleaned via a 6-in. screw conveyor. The combustion chamber is similarly lined with refractory shapes. On the 6-in. diam section, 4 1/2 in. of insulating brick, HW-26, are used. The inner combustion chamber is lined with 4 1/2-in. Korundal brick to withstand the high flame temperatures encountered. An 8-in. steel feed pipe, entering vertically through the top and fitted with an air-operated cone valve,

Jan 1, 1952

By WILLARD HAYES

(Glen Summit Meeting, June, 1911.) THE determination of the question whether the Mayari and Moa mining-claims of the Spanish-American Iron Co. have been rightly denounced under the third section of the law of bases rests on the findings in the following questions of fact: 1. Is the mineral an iron-ore? 2. Is the iron-ore a bog iron-ore? 3. Is the iron-ore ocher? 4. If ocher is present, can it be mined separately and independently of the iron-ore ? 1. IS THE MINERAL AN IRON-ORE? Since the material is shown by a large number of analyses to contain from 41. to 50 per cent. of metallic iron and less than 0.02 per cent. of phosphorus, and since it has been and is being actually used on a commercial scale for the production of iron and steel, it must be classed as an iron-ore. 2. IS THE IRON-ORE A BOG IRON-ORE? Bog iron-ore has certain invariable characteristics of chemical composition, physical appearance, geological relations, and origin by which it can always be recognized with certainty. In chemical composition, it is the hydrated sesquioxide of iron, limonite, or a mixture of limonite and other closely-related iron hydrates. It never contains the anhydrous oxides-hematite or magnetite; is never magnetic, and never contains either nickel, chromium, or cobalt oxides. On the other hand, it is invariably high in phosphorus-content. In physical appearance and texture it is a yellow or reddish-brown amorphous spongy material, and always contains water-worn sand-grains, silt, clay, and plant-remains. In its geological relations it is wholly independent of the rock

Mar 1, 1911

By C. R. Dale

The need for instruments to measure the movement of fluids and gas in wells has been recognized by engineers for many years. Information regarding flow in the producing interval has a direct bearing on completion practices in new wells and also provides information on the production characteristics of the well. Many hours of engineering time are spent in planning and completing wells but knowledge as to whether or not the original planning has produced the desired results has not always been complete. Many questions such as the following often arise: Why is it that two wells are completed under supposedly identical conditions, yet one well is a good one and the other is a poor one? Are the sands that look the best on the electric log contributing to the production? These and many other conditions in the producing well need to be under- stood in order to develop more efficient production practices and to improve on methods of completing new wells. It is the purpose of this paper to briefly describe one type of instrument, outline the methods of running the equipment and show the results of surveys made under various conditions. With an understanding of the use of this type of survey its importance can be evaluated in relation to the problems encountered by the operator. DESCRIPTION OF INSTRUMENT The instrument is a velocity recorder employing a clock-controlled 16mm film for recording the rpm of an extremely sensitive rotor which is rotated by the flow of fluids or gas in a well. The helical-vaned rotor and shaft, weighing one-half of one ounce are an integral unit exposed to the well fluids and are the only moving parts not enclosed in the fluid-tight housing. No packing or fluid seal of these parts is necessary and the shaft is mounted top and bottom on special jeweled bearings. Fig. A is the lower part of the instrument showing rotor and shaft with the protecting housing sleeve removed. The rpm of the rotor is recorded on the moving film by a combination electrical and optical system. The record is a series of dashes on the film, each dash and space representing twenty (20) revolutions of the rotor. (Film record of survey made in California well showing station recordings at various depths.) As the movement of the film is controlled by the clock the number of dashes and spaces in one minute of film travel represents the rpm of the rotor. The range of the instrument is from 0 to 2,500 rprn. The barrel or housing is 1-11/16 in. OD and seven feet long. Various types of expanding fluid traps are attached to the lower end of the instrument to direct the flow through the 1 in. orifice containing the rotor. The fluid trap for upward flow is shown in Figs. B and C. This assembly consists of eight arms with light spring

Jan 1, 1949

By C. R. Dale

The need for instruments to measure the movement of fluids and gas in wells has been recognized by engineers for many years. Information regarding flow in the producing interval has a direct bearing on completion practices in new wells and also provides information on the production characteristics of the well. Many hours of engineering time are spent in planning and completing wells but knowledge as to whether or not the original planning has produced the desired results has not always been complete. Many questions such as the following often arise: Why is it that two wells are completed under supposedly identical conditions, yet one well is a good one and the other is a poor one? Are the sands that look the best on the electric log contributing to the production? These and many other conditions in the producing well need to be under- stood in order to develop more efficient production practices and to improve on methods of completing new wells. It is the purpose of this paper to briefly describe one type of instrument, outline the methods of running the equipment and show the results of surveys made under various conditions. With an understanding of the use of this type of survey its importance can be evaluated in relation to the problems encountered by the operator. DESCRIPTION OF INSTRUMENT The instrument is a velocity recorder employing a clock-controlled 16mm film for recording the rpm of an extremely sensitive rotor which is rotated by the flow of fluids or gas in a well. The helical-vaned rotor and shaft, weighing one-half of one ounce are an integral unit exposed to the well fluids and are the only moving parts not enclosed in the fluid-tight housing. No packing or fluid seal of these parts is necessary and the shaft is mounted top and bottom on special jeweled bearings. Fig. A is the lower part of the instrument showing rotor and shaft with the protecting housing sleeve removed. The rpm of the rotor is recorded on the moving film by a combination electrical and optical system. The record is a series of dashes on the film, each dash and space representing twenty (20) revolutions of the rotor. (Film record of survey made in California well showing station recordings at various depths.) As the movement of the film is controlled by the clock the number of dashes and spaces in one minute of film travel represents the rpm of the rotor. The range of the instrument is from 0 to 2,500 rprn. The barrel or housing is 1-11/16 in. OD and seven feet long. Various types of expanding fluid traps are attached to the lower end of the instrument to direct the flow through the 1 in. orifice containing the rotor. The fluid trap for upward flow is shown in Figs. B and C. This assembly consists of eight arms with light spring

Jan 1, 1949

By W. P. Blake

FORGING under the hydraulic press, which was introduced by Haswell in the year 1861, at the machine shops of the Imperial State Railway Company of Austria, has since been greatly improved, so that at the present time there are very few parts of machines which cannot be produced in this way, and at no greater cost than iron castings. The process is now used at Vienna chiefly for such parts of locomotives as cross-heads, link-bars, axle-box frames, etc., especially where the form is intricate, and there are many angles and projections. These objects weigh from 50 to 150 lb. or more, and it is claimed for them that they are not only much cheaper than ordinary forgings, but are much more regular in form and stronger. The results which Mr. Haswell has attained, after years of patient experimenting, were well shown in the Austrian Department of the Vienna Exhibition by a collection of the pressed objects in iron and steel, just as they left the moulds, with some of them cut asunder longitudinally and the surfaces etched, so as to show the internal structure or direction of the grain. Through the courtesy of Mr. Haswell and his son I saw the hydraulic presses in full operation at the works, drawing down large Bessemer ingots, cutting them up into blocks of convenient size, and forming various parts of locomotives. They have two large hydraulic presses in use; the largest, with a piston 24 inches diameter, gives 1200 tons pressure, and the second, with an 18-inch piston, gives 600 tons pressure. The pressure in the pumps is 600 atmospheres. The action is vertical ; the piston descends upon the work, and for forging ingots is armed with a hammer-like head. An ingot of No. 7 soft Bessemer steel, which was forged in my presence, weighed 2030 lbs. One end being placed upon the anvil, the piston is brought slowly down and crowded into the mass as if it were putty or dough, forcing it each way, but chiefly in the direction of the length of the ingot, this being the narrowest section of the anvil and hammer. The piston is then raised and the ingot is moved forward for a second squeeze, and so on, until the first half of the ingot has been reduced in thickness, when it is turned on edge and the operation is repeated. The ingot is then turned end for end and forged until the whole length has been re-

Jan 1, 1874

By Woolsey McA. Johnson

In metallurgical circles it is known widely, but somewhat vaguely, that the ease of reduction of metallic oxides depends largely on the way they hare been prepared. It is likewise known that different forms of carbon have different and greatly varying reducing powers. It is the purpose of this paper to show somewhat more definitely and scientifically these facts. Some years ago the writer published an account of pyrometric determinations of the reduction temperature of zinc oxides variously prepared and of several kinds.' In said paper it was shown that the temperature at which zinc oxide evolves zinc according to the equa-tion ZnO + C = Zn + CO depends upon the nature of the two reacting bodies. The determina-tions had a range of accuracy of from 2° to 6°C., whereas differences were found to amount to an extreme of 90' C. So the differences are real ones and must have a definite cause. The equation of boiling water, (H2O)4 D 4 (H2O) has a fixed temperature for equilibrium of 100° C. at 760 mm. pressure. In general, all equations reacting in the liquid or the gaseous phase have well-defined constant physical conditions which govern the equilibrium point and reaction velocities. In a reaction where we have one or more solid phases, the tempera ture conditions requisite for the unbalancing of the stable system are found to vary. These variations are due to the fact that in a solid there is a very complex molecule and it is not a question solely of the tearing away of two interlocked atoms, but also of the destruction of a complex molecule containing hundreds, or possibly thousands, of smaller molecules. In other words, there are two forces to be overcome: a certain

Jan 1, 1914

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

0. R. LYONS*—I know that we are all interested in hearing about problems that other people have. To most of the people from the eastern part of the United States, this kind of coal preparation is completely different. It represents washing difficulties that most operators have never experienced, or, if they have, they have refused to consider them because there are coals that are much easier to wash and, therefore. they leave the more difficult ones alone for the time being. E. R. McMILLAN†—I think the au-thors have summarized the material very well. Dr. Yancey has spent a great many years in the study of washing coals, as has Mr. Geer. I might comment briefly on some of the plants that were mentioned, plants with which I have had some con-nection, particularly those of our own company, the Northwestern Improve-ment Co. I would like to point out this: that ill each case, a great deal of work was done in the way of preliminary studies of washability of the coal before plants were built. The first plant of any size built in Roslyn field was mentioned in the paper. This central cleaning plant was designed and built to handle coal from three different mines. I might say that prior to 1935, the year in which the plant was built, the coal was used largely as railway fuel, close to a million tons annually. But as mining increased in depth, it became increasingly difficult to separate and gob much of the impurities underground, with the result that the run-of-mine coal became so high in ash that the railroad eventually was forced to consider installing some kind of preparation plant at the mine. We spent about a year in preliminary studies in cooperation with the Bureau of Mines to find out the best type of plant that would clean the coal. The result, as Mr. Geer has explained to you, is a rather complicated plant, but it is doing a very satisfactory job. We have, however, made a number of changes and improve-n~euts since it was first built. The last addition was the, installation of a cen- trifugal drier to dewater the minus ¼ in. size. We are now contemplating installing heat driers for further drying of minus ¼ in. We use Vissac heat driers for drying the stoker coal, the ¾ to in. The demand for drier coal, for both railway and industrial use, is forcing us to further drying of the coal. The plant that was mentioned as having been built in Pierce County, during the war, was a government sponsored plant. I happen to have had some connection with its design, construction and initial operation. We did what we thought then, and still think, was a very thorough job of preliminary studies in cooperation with the Burea of Mines of the coal from that field. The plant was as good a plant as could be built with the equipment available at that time, 1943. The plant that was mentioned as having been built at Ravensdale for treating the McKay coal was rebuilt about two years ago, and in addition to the modified Elmore jig washer that was mentioned. we added a coucentrating table for re-cleaning the minus 3/32 in. Our object there was to produce a commercial

Jan 1, 1950

By Reginald S. Dean

THE commercial availability of electrolytic manganese has greatly changed the position of manganese as a nonferrous alloying metal. Manganese metal commercially available up to about ten years ago was reduced with either silicon or aluminum and contained substantial amounts of the oxides of these metals and other impurities. Manganese was accordingly not available as an alloy base and its addition to copper-base and nickel-base alloys was generally limited to a manganese content of a few per cent. Several special alloys like manganin contained up to 12 pct of manganese. A method for the production of electrolytic manganese was developed by the Bureau of Mines in 1936 and commercial production was begun in 1938. At the present time (June 1951), production is about 12 tons per day but appears likely to be substantially increased. Electrolytic manganese is deposited from an aqueous electrolyte containing manganese and ammonium sulphates and is marketed as cathode fragments about 1/8 in. thick. The impurities in its composition are as follows: iron, 0.0015 pct; copper, 0.001; arsenic, 0.0005; cobalt, 0.0025; lead, 0.0025; molybdenum, 0.001; sulfide sulfur, 0.017; sulfate sulfur, 0.014; insoluble, 0.002; carbon, 0.002; hydrogen, 0.015. These figures are from Bulletin 463, U. S. Bureau of Mines. From an alloying standpoint, the most important impurity is hydrogen. This can be removed by heating; 95 pct of the hydrogen can be removed in this way without introducing significant amounts of oxygen or nitrogen. Much of the commercial electrolytic manganese used in alloys is dehydrogenited by the producer, since the amount

Jan 1, 1953

A comprehensive, systematically structured mineral evaluation system is a prime requirement for objectively assessing mineral supply impacts on the economy. The Minerals Availability System developed by the US Bureau of Mines is a step in the right direction-a well-organized unraveling of the mineral supply network, structured in format to allow quick retrieval for rapid listing, supply analysis, and other uses.

Jan 9, 1977

By D. Hanson

Fox most of their practical applications metals are required to with-stand stresses of appreciable magnitude: indeed, it is because they possess the quality of resisting stress without becoming permanently deformed that they find such extensive use in the service of man. Metals and alloys must, in service, usually behave as elastic substances-or nearly so. It is not difficult to satisfy this condition at ordinary temperatures. Iron and its alloys, especially the steels, are at normal temperatures excellent elastic bodies, capable of satisfying most of the mechanical requirements of the engineer: where electrical, chemical or other properties are impor-tant, which cannot be met by steels, it is usually possible to find a non-ferrous alloy such as nickel, copper or aluminum, which will prove satisfactory. When the metals or alloys are not inherently sufficiently elastic, cold-working or heat-treatment may develop elastic properties to a sufficient extent for practical needs. By means of relatively simple, rapid tests we can measure such properties as elastic modulus, limit of proportionality and proof stress, upon which design can be based with confidence. The case of the soft metals, such as lead and tin, is well known to be exceptional. They possess no definite limit of elasticity, and the value of proof stress or tensile strength depends to a great extent on the speed with which the test is carried out. Design here must be based on other considerations than a well-established theory of the proportionality of stress and strain. It is now generally recognized that steels and non-ferrous alloys possess at temperatures not greatly exceeding that of the atmosphere, characteristics quite different from those existing at ordinary temperatures, and that they assume qualities similar to those of the soft metals. Not only have they no limit of elasticity, but the proof stress and the ultimate stress depend on the time of application of the load. Flow under load may persist for long periods of time, possibly indefinitely, and the determination of a true maximum stress becomes a matter of great difficulty.

Jan 1, 1939

EDUCATION for the mineral industry was at first a single comprehensive curriculum, but it was early recognized that the main basis of mining is physics, while that of metallurgy is chemistry. The first school to offer curricula leading to degrees in mineral industry education in the United States (1853) had separate ones in mining and metallurgy. The Columbia School of Mines (the fist really successful one) had only a single curriculum when it opened in 1864, but within a few years had so reorganized its work that it offered curricula in mining, metallurgy, geology, chemistry, and civil engineering. Interest in the metallurgy or geology curricula was slight at fist, and for the next 30 years the great majority of Columbia students took the mining curriculum, probably partly because it contained nearly as much geology as the geology curriculum, practically all the metallurgy, and most of the chemistry, and partly because of the degree awarded for it. Other schools kept their mining curricula equally broad, and as late as 1900-1910 men were graduating as mining engineers who were practically as well prepared to make geology or metallurgy their life work as they were for mining. Gradually, however, the subject matter of mining geology and metallurgy became so enriched through research and development that separate curricula in them became worth while; their progressive development is the subject of another chapter. Mining curricula also began to be somewhat diversified, and schools in areas where coal mining was of outstanding importance began to offer options in coal mining, the earlier curricula having been chiefly aimed at metal mining. The petroleum industry began its meteoric rise about the same time as mineral instruction in this country, but little more of applied science attended its birth than had attended such ancient practical arts as copper and iron

Jan 1, 1941

By HENRY JULLUM

THE ARGONAUT' mill stands at the crest and spreads down the western slope' of a hill, which incidentally covers the' outcrop of the Argonaut vein' at this point. The collar of the main shaft of the mine is situated on the eastern slope of the same hill 120 ft. below the highest ?point. The present mill, built in 1916, was designed to treat 250 tons per 24-hr. day. This capacity has not been attained recently owing to the inability of the mine to produce enough ore while extensive development and underground construction were under way. At present, however, the mine is more than able to take care of the mill requirements.

Jan 1, 1932

By J. Handin

Triaxial compression tests with independently applied external confining pressures and internal pore pressures show that the ultimate compressive strengths of representative oil well cements are nearly linear functions of effective pressure — the difference between external and internal pressures on the jacketed cylindrical specimens (to 15,000 psi). The strengths are little affected by the test temperature to 350F (not to be confused with the curing temperature). At an effective pressure of 15,000 psi, strengths are in the rage of 30,000 to 50,000 psi, comparable to those of sedimentary rocks under similar conditions. The cements become very ductile even under low effective pressures; permanent shortenings of 30 per cent or more are attainable without rupture. INTRODUCTION Since the pioneering work of Richart, Brandtzaeg and Brown1 on the failure of cement under combined compressive stresses, it has been recognized that ultimate compressive strength is greatly enhanced by the application of confining pressure. More recently, Mc Henry2 showed that the strength of concrete was a linear function of the effective pressure (the difference between the external confining pressure on a jacketed specimen and the internal fluid pore pressure), at least for a range of 0 to 1,500 psi. The effect of temperature had not been investigated, and no previous systematic triaxial compression testing of naterials used for oilwell cementing seems to have been done. The present work was suggested by the late J. hi. Bugbee3 who stated that "consideration of the common application of high-pressure hydraulic fracturing to the initial completion or recompletion of wells, and the large pressure drawdowns in some producing wells, particularly those in abnormally high-pressure gas-condensate reservoirs, raises the question of what is a suitable cement strength for various completions. The intuitive belief exists that cement strength need be no greater than formation strength. Tests should, however, be conducted at downhole conditions." The ultimate compressive strengths of rocks penetrated by the borehole must rise several fold with increasing depth.4 This marked enhancement of strength is due to the influence of the effective pressure, the total weight per unit area of the overburden less the hydrostatic pore pressure. (The effect of temperature due to the geothermal gradients is relatively small for depths to 30,000 ft.) .A significant comparison of the strengths of rocks and cements at downhole conditions requires knowledge of the confined compressive strengths of cements as well. EXPERIMENTAL PROCEDURES The theory and technique of triaxial compression testing are fully discussed in earlier reports.4-6 Briefly, cylindrical specimens 1-in. long and 0.5-in. in diameter are jacketed in thin copper tubes of negligible strength, placed in the test chamber and subjected to an external confining pressure of kerosene and loaded axially by the piston at a strain rate of 1 per cent per minute. Pore pressures of water (or kerosene) are applied independently through the hollow piston and are maintained constant during the shortening of the specimen, Tests at sensibly 0 pore pressure are arranged so that any free water in the cement can escape to the atmosphere. (If egress of water were denied, pore pressure would rapidly attain the value of the external confining pressure because of reduction of pore space.) The test chamber can be heated for high-temperature experiments. Unless otherwise noted, the cement samples were air dried for about a week. Recorded during a test are pore and confining pressures, shortening and axial differential force (total force less the product of the confining pressure and the area of the piston). True stress-strain curves are constructed by dividing the measured differential force by the actual cross-sectional area of the specimen at a given

Jan 1, 1966

By G. H. Wigton

THE oxidized ores of the Chief Consolidated Mining Co., in the Tintic mining district, have never yielded to metallurgical treatment by any standard method except smelting. These ores occur in comparatively small, irregular, siliceous replacements in limestone, and carry silver, lead, and gold as the principal valuable metals. But smelting methods. are unsatisfactory, as the lead smelters heavily penalize the large amount of silica in the ore, and the copper smelters do not pay for the lead in the ore; therefore, an alternative treatment method was sought. In 1916, a metallurgical research department was organized under; the direction of the writer. Many standard metallurgical methods were investigated but, on oxidized ore, none yielded extraction great enough to make its use feasible. During some chloridizing-roasting experiments in 1916, made in an assay muffle, the writer noted that large proportions of the silver, lead, and gold were volatilized from certain oxidized ores. The possibility of volatilizing the metals and collecting them in the form of a concentrated fume was then studied. But, as it was shown that satisfactory chloride-volatilization would be limited to a furnace feed with a high fusing temperature of the non-volatilizable constituents, and as the results obtained in a rotary kiln with the admixture of common salt with the ground ore were inferior to muffle tests, further volatilization experiments were discontinued until 1920. During this interval, an experimental sulfidizing and flotation plant was operated. After the cessation of attempts to float the oxidized minerals, chloride-volatilization experiments were resumed. The highly infusible flotation. tailing from the operation of the flotation mill was used for furnace feed. The first tests made on flotation tailing mixed with 10 per cent. common salt showed -nearly complete lead and gold volatilization but considerably less volatilization of silver than in muffle tests. In attempts to increase the silver extraction, the percentage salt in the furnace feed was varied, and it soon became apparent that the use of smaller percentages of salt raised the fusion temperature of the furnace charge and thus,

Jan 8, 1925

By Louis Ware

BEFORE the war we often heard the term "Big Business." And there were complaints of the ills and abuses attributed to bigness in business. Although there were examples where the small businessmen spoke for their rights and sought protection from the bigger ones, it has only been in recent war years that a tendency has developed definitely to divide the business of our nation into the big and the small. In some cases, those with an eye to the political value of the vastly greater number of small businessmen of the country have fomented this division by hurrying to the protection of these more numerous voters, and intentionally or not have emphasized in their writings and verbal attacks any and all differences of these interests that could either be found or fabricated to, suit the occasion. It has become another example of breaking the people into classes and thus setting up the basis for the claims of one class against another, and the subsequent demand for legislation and Governmental aid. The terms "big" and "small" are purely relative. One businessman, employing a hundred men, told me recently he did not know which adjective would be more appropriately applied to his operation. He did not know whether he should join the small operators' group that had been organized, or should consider himself big. He said that his present plant seemed big to him when he looked back to its humble beginning many years ago with a couple of men in two rooms. Yet, when compared with many of his competitors who employ thousands, his was small. He did add, however, that he probably became big one day a few years ago when the union moved in and organized his employees.

Jan 1, 1945

By T. G. Lovering

Nonparametric statistical tests have practical application to many geological problems because, unlike the standard statistical tests, they do not require assumptions regarding the form of the population frequency distribution. Many of them do not even require that the variable be susceptible to numerical measurement. These tests are useful either 1) for geological data representing population distributions of unknown form, or otherwise not meeting the requirements for standard parametric tests; or 2) for sample attributes that cannot be measured but only ranked in order of relative magnitude. The application of two such tests will be illustrated. The Kolmogorov-Smimov test will be used to test for significant differences in copper distribution in samples of two rock types; the Spearman rank-correlation method will be used to determine whether there is a significant association between intensity of rock alteration and copper content of the rock. Nonparametric tests are, in general, quicker and easier to perform than the corresponding parametric tests, and they may be applied to a greater variety of data. They are not as powerful as the standard tests if used on data to which the latter are applicable, and computer programs utilizing them are not generally available. The use of standard or parametric statistical procedures for the interpretation of measured geological data is familiar to most mining engineers and explora- tion geologists. The computation of product moment correlation coefficients on sample assays for more-than one component is already standard procedure in some company operations, as is the use of Student's F test and Snedecor's F test for the comparison of means and variances of sample groups. The application of these three tests is limited by the prerequisites that the samples must be random, independent representatives of normally distributed populations and that the variables involved must be measurable. If such tests are applied to data which fall short of fulfilling these prerequisites, then the probability level attributed to the computed statistic is invalid and the conclusions based thereon may be erroneous. A number of nonparametric, or distribution free, statistical tests have been developed for use with data which are not amenable to standard parametric procedures. These tests have been widely used in the behavioral sciences such as psychology and sociology for some time, but their application to geologic problems is relatively new. Nonparametric tests may be grouped into two main categories: those which test for significant differences in a single variable by comparing either sample values with a standard value or representative values between two or more groups of samples; and those which test for significant association between pairs of variables in a single group of samples. The versatile chi square test, the Kolmogorov-Smirnov one and two sample tests, the Wilcox matched pairs signed ranks test, the median test, the Mann-Whitney U test and the Cochran Q test are examples of nonparametric tests with demonstrated or potential geological applications that belong in the first category. The contingency coefficient, Spearman rank correlation coefficient, Kendall rank correlation coefficient and the

Jan 1, 1963

By A. E. Dwight, A. F. Berndt

Binary and ternary alloys of uranium with transition metals were prepared with U2X stoichiometry. The compounds U2Tc, U2Rh, U2Os, and U2lr were formed by peritectic or peritectoid transformations, and were shown to be isostructural with U2Ru. The lattice constants are presented. Miscibility relationships obtained from the study of ternary alloys are graphically summarized in terms of an area-of-stability plot. The compound U2Re is not isostructural with either U2Ru or U2Mo. A series of compounds with stoichiometry U2X has been prepared in which X is technetium, rhodium, rhenium, osmium, or iridium. The only other U2X compounds, for which X is related to the above transition metals by proximity in the periodic table, are U2Mo and U2Ru. The structure of U2Mo is the tetragonal C11b type (MoSi2 type)1 and U2Ru is monoclinic, with a new structure type.' This investigation was undertaken to determine if any of the above compounds are isostructural with either U2Ru or U2Mo and to find the range of occurrence of these phases. EXPERIMENTAL Alloys were prepared from stoichiometric amounts of electrolytic uranium (99.99 pet pure) and transition metals of 99.5 pet purity (98+ pet pure Tc), by arc melting on a water-cooled copper hearth under an Ar-He atmosphere. Weight losses were negligible. The buttons were homogenized at temperatures between 700o and 800°C (900°C for U2Tc) in evacuated capsules and air-cooled. The X-ray powder specimens were annealed briefly at the temperature of homogenization. Except in the case of the technetium alloy, metallographic examination was used to determine the number of phases present. The radiation hazard involved in handling technetium precluded the use of metallography to examine U2Tc. The temperature and mode of formation of the U2X phases were determined by heating the metallographic specimens to successively higher temperatures, until examination indicated the presence of chilled liquid or a peritectoid transformation. RESULTS The U2X compounds investigated were found to be formed under the following conditions: UzTc unknown U2Ru peritectic 897o ± 3°C U2Rh peritectoid 755o ± 5°C U2Re peritectoid3 below 750°C Uas peritectic4 920°C U2Ir peritectoid 775o ± 5oC Debye-Scherrer patterns for the above U2X phases were made with CuKa radiation (nickel filter). The similarities in the positions and intensities of the strongest lines in the front-reflection region strongly suggested that U2Tc, U2Ru, U2Rh, U2Os, and U21r are isostructural with only minor differences in the unit-cell dimensions. The known lattice constants and intensities of the Debye-Scherrer rings for U2RU2 were used as a guide in order to index the low-angle X-ray reflections of the U2TC, U2Rh, U2Os, and U2Ir powder patterns. Approximate lattice constants for these compounds were thus obtained and were used along with the intensities observed for U2Ru to index the strongest lines in the back-reflection regions. A sin2 2? correction term was included and the lattice constants were refined and standard deviations estimated by least squares. Comparison of observed and calculated values of Q(= 4 sin2?/?2) used in these calculations are given in Table I. In each case when the positions of lines could not be resolved on the films they were not measured. The final lattice constants, with their standard deviations, are given in Table 11, along with the unit-cell volume and X-ray density. The values of the atomic volume5 of the transition ele-

Jan 1, 1965

By J. F. Lewis

BELIEVING that one of the essential points in mining, as in all other business, is to know the expense incurred in each particular department, I have carefully kept an account with each department for the past three years; and, as it may be of interest to some of our members, I herewith present it to the Institute, reduced to percentages of the total yearly expense, showing the cost for materials, repairs, expenses, tools, team accounts, powder, oil, and fuel, also for labor under its several heads :

Jan 1, 1878