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By G. Gutzeit

METAL-ORGANIC INNER COMPLEXES AN inner complex is a cyclic chemical structure containing an inorganic cation that is bound simultaneously to several atoms in a single organic molecule; on the one hand by means of ordinary valence bonds (electron exchange), on the other hand through the action of the electric field thus created, which satisfies the so-called secondary valences. The relative positions of the salt-forming and complex-forming groups are such that most frequently a four, five, or six-membered ring results through this double attachment of the cation.1-6 The formation of inner-complex ring systems depends not only upon the nature and suitable position of the salt-forming and complex-forming groups for ring closure, but, to a great extent, also on the nature of the metallic cation entering the reaction. This selective character of chelate-forming organic compounds is one of their most interesting and most valuable properties. As a matter of fact, the largest number of their practical applications is based upon their specificity. 4,1-13 Once a chelate compound is formed, its character is definitely "organic" in nature. In other words, its properties are conditioned to a much larger degree by the carbon chains or rings than by the metallic atom. Many inner complexes are soluble in nonpolar solvents such as benzene, paraffin oil or carbon tetrachloride, while the chelate-forming reagent before closure of the metal-organic ring is water soluble. (Example: copper complex of salicyl-aldoxime.) It is obvious that such particular properties as those indicated above can be utilized whenever specificity and practically complete binding of inorganic ions into an undissociable complex are required. One of the well-known applications of chelate-forming compounds has been the development of specific reagents in analytical chemistry,, creation of the spot-test method,4,14-16 and the application of the same principles to the contact print method for determining minerals.17 CHELATE-FORMING COMPOUNDS AS COLLECTORS In the field of flotation, where selectivity is often a quality of paramount importance for the collector, various workers have lately attempted to apply their knowledge of specific organic analytical reagents to this purpose. A. C. Vivian18 has concentrated cassiterite by using ammonium nitrosophenylhydroxylamine (Cupferron) C6H5NO(=NONH4). Holman19 has tested dimethylglyoxime for the flotation of nickel oxide minerals, while deWitt has shown in a series of systematic experiments that alpha-dioximes were generally selective collectors for nickel ores. Taurin NH2(CH2)2SO3H has been proposed for the concentration of oxidized lead ores.19 Diphenylthiocarbazone

Jan 1, 1946

By J. W. Spretnak, G. W. Powell, J. H. Bucher

Tlze room-temperature tensile fracture oj smooth, round specitnens of three ultrnhigh- strength steels tempered to a wide range of strength levels was studied by means by light and electron-microscopic examination of the fracture surfaces. The fracture of AISI 4340 and 300 M at all the strength levels studied, and H-11, except after tempering at 1200° and 1300°F, occurs in three stages. The initiation of fracture is internal (except in some lightly tcmpeved specimers in which fracture is initiated at surface flaws), and is nucleated largely by separation at metal-second phase intevjaces. TIze voids grow and, coalesce to form a crack. When the crack has reached a sufficienl size, rapid propngutio~z ensues. Failure in this stage of fracture usually occurs by dimpled rupture of inicroshear stefis. In the case of H-11 tempered in the 1125° to 1300°F range, fracture in the shear steps is predominantly by concentrated deformation without void formation. The termination of fracture is usually occomplished by the formation of a shear lib in which fracture occurs by shear dimpled rupture. In the case of H-11 tempered at 1200° and 1300°F, no shear lip was obserued, and the radial elelments extend to the surface—a true termination slage does not exist. ThE tensile fracture of several metals and alloys has been investigated.2-4 In the case of polycrystal-line materials, cup-cone fracture usually results. The mechanism of cup-cone fracture may be summarized as follows.5 Cavities are formed in the necked region of the specimen. They usually are initiated by inclusions or second-phase particles. The cavities extend outwards by means of internal necking, and a crack lying about perpendicular to the length of the specimen is formed in the necked region. Subsequent crack growth occurs by the spread of bands of concentrated plastic deformation inclined at an angle of 30 to 40 deg to the tensile axis. Cavities are formed in the bands of concentrated deformation. The deformation bands zigzag across the bar with the net result that mac-roscopically the crack extends about perpendicular to the specimen axis. The final separation, or cone formation, appears to occur by continued crack propagation along one of the deformation bands out to the surface of the specimen. The micromechanics of the tensile fracture of ultrahigh-strength steels have not been thoroughly investigated. Larson and carr6,7 studied the tensile-fracture surfaces of AISI 4340 with a low-power microscope and reported that three stages of fracture could be observed in general. A centrally located region characterized by circumferential ridges, an annular region characterized by radial surface striations, and a peripheral shear lip were found. It was first pointed out by 1rwin8 that the central region is very probably one of fracture initiation and slow growth, and that the annular, radially striated region is one of rapid crack growth. Presumably the crack grows slowly, assuming roughly a lenticular shape, until it is large enough for the initiation of rapid propagation. In this investigation, it was attempted to determine the fine-scale aspects of the room-temperature tensile fracture of some ultrahigh-strength steels, and to relate the variation in fracture mode with microstructure. The steels studied were AISI 4340, 300M, and H-11 tempered to a wide range of strength levels. I) EXPERIMENTAL PROCEDURE The compositions of the steels studied are given in Table I. The steel was received in the form of hot-rolled bar stock 5/8 to 1 in. in diameter from which oversized specimens were machined and heat-treated. The heat treatments employed are given in Table 11. Subsequent to heat treatment, the specimens were ground to the final dimensions and stress-relieved by heating for 1 hr at 350°F (with the exception of the as-quenched steel). Standard smooth round specimens of 0.252-in. diameter and 1-in. gage length were tested in a Tinius Olsen Universal Testing Machine using a cross-head speed of 0.025 in. per min. The relatively coarse aspects of the fracture topography were determined by light-microscopic examination of sections through the fracture surface of nickel-plated specimens. A direct carbon-replication technique9 was used in the electron-microscopic study of the fracture surfaces. The replicas were examined in the electron microscope, and stereo pairs of electron micrographs were taken. The stereo pairs were then examined using a Wild ST4 Mirror Stereoscope. Carbide and inclusion particles extracted in the replicas were analyzed by selected-area electron diffraction. II) EXPERIMENTAL RESULTS The mechanical testing data are summarized in Table 111. The values reported are the average of

Jan 1, 1965

By John Chipman, Minu N. Dastur

This paper presents equilibrium data on the reaction of water vapor with vanadium dissolved in liquid iron at 1600°C. The thermo-dynamic behavior of vanadium and oxygen when present together in the melt is discussed. A deoxidation diagram is presented which shows the concentrations and activities of vanadium and oxygen in equilibrium with V209 or FeV2O4. STUDIES of the chemical behavior of oxygen dissolved in pure liquid iron1-3 have served to determine with a fair degree of accuracy the thermody-namic properties of this binary solution. The practical problems of steelmaking, however, involve not the simple binary but ternary and more complex solutions. Only a beginning has been made toward understanding the behavior of such systems. The silicon-manganese-oxygen relationship was studied long ago by Korber and Oelsen4 and more recently by Hilty and Crafts." The carbon-oxygen reaction was investigated by Vacher and Hamilton6 and by Marshall and Chipman.7 A number of deoxidizing reactions have been studied empirica1lys'10 with the object of determining the appropriate "deoxidation constants." The work of Chen and Chipman" afforded a clear-cut view of the effect of the alloy element, chromium, on the thermodynamic activity of oxygen in liquid ternary solutions. These investigators determined the oxygen content of experimental melts which had been brought into equilibrium with a controlled atmosphere of hydrogen and water vapor and were able to show that the presence of chromium decreases the activity coefficient of oxygen. They determined also the conditions under which the two deoxidation products, Cr2O3 and FeCr2O4, were formed and showed that the activity of residual oxygen is considerably less than its percentage. It was the object of this investigation to apply a similar method to the study of molten alloys of iron, vanadium, and oxygen. Vanadium was once considered a moderately potent deoxidizer, but this is now known to be erroneous, in the light of its behavior in steelmaking practice. Its reaction with oxygen retains a certain amount of practical interest in that a high percentage of one element places a limit on the amount of the other that can be retained. As a deoxidizer it will be shown that vanadium lies between chromium and silicon. Experimental Method The apparatus was that used by the authors3 in their study of the equilibrium in the reaction: H2(g) +O = H2O(g);K,= [1] PII., ao Crucibles of Norton alundum or of pure alumina were used. The latter were made in this laboratory and were of high strength and low porosity. Under conditions of use they imparted no significant amount of aluminum (less than 0.01 pct) to the bath. Temperature measurements were made with the optical equipment and calibration chart of Dastur and Gokcen.= The charge was made up of calculated amounts of ferrovanadium (20 pct V) and clean electrolytic iron totaling approximately 70 g. The first few heats were made in alumina crucibles with an insufficient amount of vanadium so that no oxide of vanadium would be precipitated under the particular gas composition. All the heats were made at 1600 °C under a high preheat and with four parts of argon to one part of hydrogen in the gas mixture to prevent thermal diffusion. The rate of gas flow was maintained constant at 250 to 300 ml per min of hydrogen. The time for each heat was three quarters of an hour after the melt had melted and attained the required temperature (1600°C). The water-vapor content of the entrant gas mixture was gradually raised in succeeding heats, keeping the vanadium content of the melt constant. This was controlled by manipulation of saturator temperature. A point was reached when for a given H2O:H2 ratio some of the dissolved vanadium was oxidized and appeared as a thin, bright oxide film on top of the melt. By raising the temperature of the melt it was possible to dissolve the oxide film which reappeared as soon as it was cooled down to 1600°C. The temperature readings taken on the oxide film were consistently higher by 80" to 85 °C as observed by the optical pyrometer. The heat was allowed to come to equilibrium under a partial covering of this oxide film. At the end of the run the power and preheater were shut off and the crucible containing the melt was lowered down into the cooler region in the furnace. This method of quenching proved quite

Jan 1, 1952

By F. W. Bradley

This chapter on the Alaska Juneau mill is intended to make clear that "choice of methods," or the selection of proper methods, is the first essential step in launching a new enterprise; and to illustrate that when entering into new country where local conditions and physical features are new or strange to an engineer, he should respect the practices already adopted and followed in meeting peculiar conditions in these new countries that may seem strange to a casual visitor. For example, Americans going into Malay Peninsula with their most up-to-date machinery for drilling placer prospect holes found their cost to total about $3 per foot; by adopting native methods, it was found the same work could be done for 50 cents per foot. Also, those not used to frozen road conditions in a country of arctic climate might scrape the snow off such a road and cause unending road troubles into the following spring and summer; while natives understanding local conditions would leave the snow on the road. So in the neighborhood of Juneau, Alaska, where successful gold-milling operations had been going on for

Jan 1, 1932

By R. I. Jaffee, C. M. Craighead, G. A. Lenning

Hydrogen forms a beta-stabilized system with titanium, with a beta eutectoid at about 300°C and 44 atomic pct H2. 'The solid solubility of hydrogen in alpha decreases from about 8 to about 0.1 atomic pct from 300°C to room temperature. Hydrogen has little effect on tensile properties, but decreases notch-bar toughness to a large degree. This latter effect appears to be the result of increased notch sensitivity. PRIOR to this investigation, only a small amount of information was available on the effect of hydrogen on the mechanical properties of titanium. The effects of the other interstitially soluble elements, carbon, oxygen, and nitrogen, had received detailed study. Jaffee and Campbell1 indicated that hydrogen up to 1 atomic pct did not affect tensile properties deleteriously. Pitler' indicated that 1 atomic pct H, in titanium reduced the impact strength appreciably, but his alloys contained appreciable amounts of oxygen, and it was difficult to attribute the embrittlement entirely to hydrogen. The high temperature portion of the equilibrium diagram for the Ti-H system was established by McQuillan," and his data generally corresponded with the results of Kirschfeld and Sieverts," Gibb and Kruschwitz," Bevington, Martin, and Mathews," and other investigators. The lower concentration limit of the hydride phase varied considerably among investigators, and Gibb and Kruschwitz9 ad shown that small amounts of contaminants in either titanium or hydrogen caused considerable variation in this lower limit. In view of this pronounced effect of contaminants, the extrapolated value of McQuillan's, about 48 atomic pct at the 325°C eutectoid, appeared the most reasonable. McQuillan's lowest experimental value was 54 atomic pct at a temperature of 450 °C. The density of titanium had been shown to decrease with increasing hydrogen content, but discrepancies were noted among the various investigations. The best values indicated that the density was decreased from 4.56 grams per cc at 0.27 atomic pctl to 3.84 grams per cc at 61.3 atomic pct? This investigation was conducted to determine the effects of hydrogen on a titanium, both in high purity and commercially pure metals, and on high purity a titanium alloys. Material and Fabrication The literature indicated that impurities in either the hydrogen or the titanium must be kept to a minimum. For this reason, the initial studies were made with high purity iodide-refined titanium. The vendor's analysis of the iodide titanium and the hydrogen content of the as-fabricated Y4 in. diameter rods are shown in Table I. Two 1 lb ingots were prepared by arc melting under argon in a water-cooled crucible, using a water,cooled tungsten electrode. This equipment has been described.' As-cast Brine11 hardness numbers of 88 and 58 for these ingots were low enough to insure that the high purity of the metal was maintained during arc melting. The ingots were hot forged to % in. diameter rods at 800°C, cleaned by grit blasting, and then cold swaged to Yz in. diameter rods. The rod was then air annealed at 725 "C, ground to remove scale, and cold swaged to Y4 in. diameter (75 pct reduction in area). The material was then annealed for 1 hr in argon at 800°C to develop an equiaxed a grain size of about 0.05 mm. Micro tensile specimens and microimpact specimens were machined from this rod prior to treatment in the Sieverts-type absorption apparatus. Two lots of commercially pure RC-55 titanium were also used in this investigation to determine the effects of hydrogen and the normal impurities on mechanical properties. The commercially pure RC-55 alloy was obtained in the form of % in. diameter rod. The analysis of this material is also given in Table I. The % in. diameter rods were hot swaged

Jan 1, 1955

By L. R. Jackson, W. T. Lankford, K. F. Smith

ComMercial steel sheet is prepared by a combination of hot and cold rolling and annealing. This treatment usually results in more or less pronounced anisotropy. The anisotropy may manifest itself both as preferred orientation and in the manner in which impurities, segregations, and the like, are aligned in the sheet. The type of preferred orientation and the organization of impurities or segregations may affect the elastic moduli, the yield strength, the tensile strength, and almost always the amount of ductility in different directions. In any case, the most important directions concerned in the anisotropy are along the rolling direction, along the width direction, and along the thickness direction. Considerable data exist on the anisot-ropy of sheet steel as demonstrated by conventional tensile tests; however, few attempts have been made to measure the constants of plastic anisotropy and use them to describe the flow of anisotropic sheet under combined stresses. In this paper, evidence is presented indicating that plastic flow in anisotropic sheet can be described by the shear-strain energy flow theory provided that the anisotropy is properly taken into account. Materials Used in the Investigation Table I lists the sheet materials used in this investigation and describes the condition in which materials were tested. Direction, of Tests and Test Methods Two types of tests were run—tensile tests and hydraulic-bulge tests. Characteristic parameters of anisotropy were determined from the tension tests by methods which will be described later. In all cases, the tensile test pieces were cut from the same quarter line and adjacent to the bulge test pieces in the sheet in order to minimize

Jan 1, 1949

By W. L. Austin

The only essential difference among the three methods of collecting the precious metals from their low-grade ores by fusion is comprised in the nature of the vehicle in which those metals are concentrated. If lead- or coppper-ores are used, the processes are respectively lead- or copper-smelting; but when the sulphide of iron forms the matrix in which the gold and silver are collected, the process is known as pyritic smelting. The latter method presents rarely any advantages when lead- or copper-ores are available at rates which permit profitable treatment. Pyritic silver-smelting, defined by Percy as " the smelting of silver-ores, which are either free from lead or do not contain it in sufficient quantity to collect the silver, in conjunction with pyrites, in order to produce a regulus in which the silver may be concentrated," is not, as the name would imply, confined to ores of this metal alone, but embraces auriferous silver-ores, or even gold-ores simple. This method of collecting the precious metals from lowgrade dry ores, employed at Freiberg by Barthel Kohler in 1585, does not appear, up to the present, to have been introduced into this country on a working scale. And yet the possibility of getting rid in a single operation of all the earthy or siliceous gangue of a lowgrade ore and concentrating the precious metals in a matte without loss of lead (which includes gold and silver) by slagging, or volatilization, at the same time producing a highly siliceous slag, very nearly if not quite as clean as is usual in lead-smelting, certainly commends itself. In some parts of the country, owing to the com-

Jan 1, 1888

By H. J. Wasson

With the close of 1932 and the third year of the depression, the activity of oil production presents, amidst the general wreckage and chaos of industrial society, a somewhat unique picture of rationalized economic effort. How long it will continue to present such a picture, however, is a subject for conflicting surmises. East Texas still dominates the contemporary horizon, but it has become, at least for the time being, a definitely known factor. With its 9500 wells it is approximately 90 per cent drilled up. So long as production control obtains, it is merely one important factor of the national oil reserve. Domestic Production The notable new discoveries in the United States were less numerous than for several years. Elsewhere in the world the record is much the same. The Conroe field in Montgomery County, Texas, lying in an intermediate zone that might be classified either as Gulf Coast or East Texas, represents perhaps the single example of a truly major discovery during the year. Elsewhere in Texas the new pool discoveries, about a dozen or so in number, were nearly all in the region known as Southwest Texas. Oklahoma contributed seven or eight new pools of the routine "run-of-mine" caliber, and the opening up of a few deeper oil pays also were of some significance. Continued expansion of the proved and semiproved reserves in Kansas added an important increment to the oil resources of that state. In California not a single new field was added to the roster, though deeper pay zones equivalent to or of greater importance than many new fields in other parts of the country were discovered or indicated. The new deep zone in the Belridge field is considered by some to underlie the prolific Temblor and may thus forecast the widespread distribution of a potentinl oil horizon underlying many San Joaquin Valley fields below the depths thus far exploited. Aside from the routine operations in connection with settled production, the Eastern fields were decidedly inactive. Further new develop-

Jan 1, 1933

By C. A. Hartnagel, D. H. Newland

Detailed production statistics listing the operations according to producing sands, districts, etc., are not available for New York State and are scarcely obtainable without extraordinary effort and expense, hardly warranted by the current rate of developments. The oil industry is practically stabilized, so far as exploration for new sources of supply are concerned; no new pools have been tapped in the last 25 or 30 years. There is little prospect of extending the boundary of the oil fields beyond their present limits, though possibly some additional reserves may be found below the present productive sands. Natural gas, on the other hand, is not restricted to such confined areas. Drilling for gas has been fairly active, under the stimulation of some important finds in formations that previously were overlooked. The year's field operations will be covered somewhat fully. Oil production, which has been steadily advancing for a number of years, showed a further moderate gain in 1936. The output for 11 months (figures for December are not yet available) was 4,217,000 bbl., indicating a total for the year of around 4,600,000 bbl. The increase was about 10 per cent, a rate maintained for some time. Prices were more satisfactory than in the preceding five years, with an advance to $2.57 a barrel before the year's close. New York State yield is all paraffin-base, in the same class with high-grade Pennsylvania oil. Most of the output is now obtained by the water drive, which has given a new lease of life to the fields and promises to bring the total to about 200,000,000 bbl. before the known acreage has been exhausted by this method. Before its introduction the annual production was under 1,000,000 bbl. a year. The fields cover an aggrcgate area of 55,000 acres, with some 17,000 wells in operation. Development Exploring for natural gas in New York in 1936 outside of the old established pools continued actively, as in the previous year. There was an increase in total initial production. Operations were conducted in nine counties of the central and western parts of the state, and 43 wells

Jan 1, 1937

PERSONAL (Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who registered at Institute headquarters during the period Oct. 10 to Nov. 10, 1914: Jintaro Kojima, Ashio, Japan. E. R. Hinckley, Seoul, Korea. J. Homer Stover, Trenton, N. J. S. A. Taylor, Pittsburgh, Pa. Kirby Thomas, New York, N. Y. Lawrence Addicks, Douglas, Ariz. Keijiro Nishio, Tokyo, Japan. Noel Cunningham, Bethlehem, Pa. Alexander K. Hamilton, Chicago, Ill. E. C. Vigeon, London, England. Harold N. Lawrie, Portland, Ore. S. E. Fairchild, Jr., Philadelphia, Pa. C. Spence Thomas, Cardiff, Wales. W. C. Schmidt, Jr., New York, N. Y. Henry Tackmann, New York, N. Y. Kenneth C. Browne, New York, N. Y. Dr. David T. Day has resigned his position with the U. S. Geological Survey and opened an office at 1331 F Street, N. W., Washington, D. C., for practice as a consulting engineer.

Jan 12, 1914

By John Greenawalt

IN view of the increasing importance of sintering in the beneficiation of iron ores preparatory to their reduction in the blast furnace, the writer believes the time is opportune for an up-to-date, though brief, discussion of the general principles of sintering, as well as a discussion of some of the recent improvements and mechanical developments that have been achieved in this industry, its present trend and future possibilities. Sintering may be defined as the agglomeration of fine mineral particles into a porous mass by incipient fusion caused by heat produced by com-bustion within the mass itself. Its first successful application, in connec-tion with the treatment of lead sulphide ores, was known as blast roasting. In this process the lead ore was given a preliminary roasting in a reverber-atory furnace, then the incandescent mass was placed in a pot with a grate and an updraft was applied. It was soon discovered that much better results were obtained by cooling the ore, moistening it, and placing it upon an incandescent layer of fuel previously placed upon a grate, and then applying the updraft blast of air until the charge was converted into a more or less agglomerated mass. The fuel was sulphur and the process one of desulphurization, which was the principal result desired. The application of downdraft to blast roasting brought about tremen-dous results; the principal one of which was that an air blast of high pressure could be passed through a layer of ore deposited on a grate, or on a grate covered by a layer of coarse porous material, without disturbing the particles of which the layer is composed. The air current is compelled to filter through the pores of the charge, whereas if the same pressure applied to the top surface of the charge with downdraft were applied to the bottom of the charge with updraft, the charge would be completely blown off the grate. Another result of reversing the draft was that a flame could readily be applied to the top surface of the charge for ignit-ing purposes.

Jan 1, 1938

By Henry Fernald

THE accounting system or bookkeeping methods of any company are principally the concern of that company and of those who are in control of its affairs. Its published financial report is, however, primarily intended for those who are not already fully informed regarding its operations and finances. Whatever may be the advantages of standardization of accounting and bookkeeping methods, it must be admitted that a company has a certain right to handle its accounts and keep its books and records in whatever manner may seem to it best adapted to its affairs, even though such methods may differ materially from those generally adopted by others. In its financial reports it should not, however, either ask or expect that the statements it makes or the terms which it uses will be given in its case a meaning and interpretation different from that which they are ordinarily considered to have in similar reports and statements of other companies. The particular form and arrangement of such reports is a matter concerning which there may be much difference of opinion. It is of little importance whether current assets come first or last in the Balance Sheet, but it is important that there should not be included under this designation any items which are not properly current assets within the generally accepted meaning of that term. The extent to which stockholders or others interested are to be made acquainted with the full details of a company's business is a question which the proper authorities must in each case decide. It should, however, be recognized that there are certain facts regarding a mining com-pany which must be set forth in a financial statement if it is fully to cover the conditions and affairs of the company. For example, a financial, statement which does not include or is not accompanied by a statement, of the ore reserves of the company does not fully set forth its financial condition. This is true whether the absence of such a statement of ore reserves is because it is not desired to make public the figures or whether it is because the ore reserves themselves are not definitely known, or accurately measured.

Jan 1, 1928

University of New Mexico, Albuquerque, N M Requests for publications should be addressed to the Librarian of the University Papers of the Geological Series of the University are bound in volumes: Vol 1, vol 2, pt 1, and vol 2, pt. 2, and vol. 3 are out of print, but separates of the following papers may be had at a uniform cost of 25 cents each. Vol. 1? No. 1, Geology of the environs of Albuquerque (1898); 2, Occurrence of copper and lead in the San Andreas and Caballo Mountains (1898), 3, Geological reconnaissance in western Socorro and Valencia counties (1898); Geology of the San Pedro and Albuquerque districts (1898). , Vol 2: No. 1, Geology of the Albuquerque Sheet (1900); 2, Miscellaneous economic papers by Herrick (1900); 3, Geological reconnaissance in western Socorro and Valencia counties (1900); 4, Geology of the White Sands of New Mexico (1900); 5, Identifi¬cation of an Ohio coal measure's horizon in New Mexico (1900); 6, Cyanide process in New Mexico (1900). Vol. 3. No 3, The oil situation in New Mexico (1920), 4, Geology of Sandia Mountains (1922); 5, Oil and gas m New Mexico in 1923.

Jan 1, 1933

By A. R. Jr. Amos

LOG washers have been used for many years in the washing of clay iron ores, phosphate rock and manganese ores, but not until the past 15 years have they been employed to any extent in the preparation of aggregate materials and fluxing stone. For a machine of such importance where tenacious clay or soft rock must be eliminated, there are few data generally available. The purpose of this paper is to set forth the results obtained from several operations, together with a few suggestions for planning a specific installation. Where the material to be washed out consists of loose surface soil, silt, or small amounts of quickly soluble clay, there is little competition with other forms of washers, because greater power and maintenance are required for the operation of log washers, but where the foreign matter is a stiff clay, such as occurs with high-calcium limestones and in marginal gravel deposits, the ability of other kinds of washers to eliminate com-pletely the hard clay balls is at least uncertain. Then the log washer comes into its own field, for with the breaking and churning action of the logs it will clean out the toughest clay. Even with material from the hydraulic dredge, if it contains tough clay, the log washer is desirable unless the gravel is subjected to a costly soaking and rehandling process. Recently there has been a considerable development in other types of machines to accomplish these results but it is not within the scope of this paper to make comparisons between competitive types, but to present the best obtainable data on log washers only. From the primitive design that gave it its name, a long log hewn from a tree, with paddles forged to shape from strap iron and attached by lag screws, the log washer has gradually been developed to the present all-steel type. As now manufactured, the log washer consists essentially of two built-up logs on which are mounted a series of paddles, carried by shafts fitted at the ends of the logs on bearings fastened outside the enclosing steel box, or trough, which is set at an angle of about 5° to 10° and into which the material is fed. Stuffing boxes at the places where the shafts pass through the box at the lower end are equipped with water-

Jan 1, 1936

By Thos Gibson

THE object of taxation is the raising of a revenue. Unless a tax accomplishes this, it is a failure. The right to take for public purposes a part of the moneys obtained from the carrying on of private enterprises is an attribute possessed only by a lawful government, and may indeed he called the supreme attribute of government. In free, democratic communities this power must of necessity rest upon the consent of the governed. Power implies obligation, hence it is obviously the duty of a government, in framing a system of taxation, to provide one which, while effective in producing a revenue, is also just and impartial. It will be conceded that mines and mining property ought to bear a fair share of the public expenditure. The question is, upon what basis taxation should proceed. Two separate taxing principles are usually contended for: Taxation should be proportionate to the benefits received by the person or property taxed; taxation should be based on ability to pay. A third is sometimes added, taxation should have reference to the extent and value of the natural resources enjoyed. As applied to mining taxation, it is pointed out by those who support the first mentioned basis that, mines being usually situated in rocky and hence sparsely peopled regions, mining companies are frequently obliged to construct roads, railways, telegraph and telephone lines, schools, water and sewerage systems, and many other amenities and conveniences of civilization, the cost of which in regions better suited for agriculture and consequently more thickly populated, has either been defrayed locally, or can be spread over a sufficiently large taxable group of people to materially lighten the financial burden on the mine. The mining com¬pany, it is argued, having made these outlays, should receive credit for, them and be relieved of taxation to a corresponding extent. There may be some force in this contention, but the situation is capable of relief without attempting to place taxation upon so unworkable a basis as the value of benefits received. Who is to be the judge of these benefits, and how are they to be valued? The very existence of a mining company and its ability to carry on business in peace and security, depend on the prevalence of law and order, which is a result of good government. The state provides protection against violence, and courts of law for

Jan 4, 1919

By A. R. Jr. Amos

LOG washers have been used for many years in the washing of clay iron ores, phosphate rock and manganese ores, but not until the past 15 years have they been employed to any extent in the preparation of aggregate materials and fluxing stone. For a machine of such importance where tenacious clay or soft rock must be eliminated, there are few data generally available. The purpose of this paper is to set forth the results obtained from several operations, together with a few suggestions for planning a specific installation. Where the material to be washed out consists of loose surface soil, silt, or small amounts of quickly soluble clay, there is little competition with other forms of washers, because greater power and maintenance are required for the operation of log washers, but where the foreign matter is a stiff clay, such as occurs with high-calcium limestones and in marginal gravel deposits, the ability of other kinds of washers to eliminate com-pletely the hard clay balls is at least uncertain. Then the log washer comes into its own field, for with the breaking and churning action of the logs it will clean out the toughest clay. Even with material from the hydraulic dredge, if it contains tough clay, the log washer is desirable unless the gravel is subjected to a costly soaking and rehandling process. Recently there has been a considerable development in other types of machines to accomplish these results but it is not within the scope of this paper to make comparisons between competitive types, but to present the best obtainable data on log washers only. From the primitive design that gave it its name, a long log hewn from a tree, with paddles forged to shape from strap iron and attached by lag screws, the log washer has gradually been developed to the present all-steel type. As now manufactured, the log washer consists essentially of two built-up logs on which are mounted a series of paddles, carried by shafts fitted at the ends of the logs on bearings fastened outside the enclosing steel box, or trough, which is set at an angle of about 5° to 10° and into which the material is fed. Stuffing boxes at the places where the shafts pass through the box at the lower end are equipped with water-

Jan 1, 1936

By Alfred Weiss

The Daniel C. Jackling Award, established in 1953, is presented for significant contributions to technical programs in mining, geology, and geophysics. This year's recipient, Alfred Weiss, was cited "For his pioneering achievements in applying systems analysis, operations research, and computer methods in exploration, mining, and environmental control; and in disseminating the new technology to the worldwide mining community; and for his lecture, “New Concepts and Tools in Decision-Making.”

Jan 1, 1979

By Donald Barton

THIS paper outlines a time-saving graphical method of calculation for application to the interpretation of observations with the Eötvös torsion balance. Preliminary to the treatment of this short cut method which has been found practicable, the principal formu-las by which the student of interpretation can calculate the gradient and differential curvature produced by different types of bodies in different types of situa-tions are presented and discussed. It is necessary to split most geologic bodies into a series of simpler ones for which not too complicated formulas are avail-able. The gradient and differential curvature effects are calculated for each of the simple bodies and then summed to the total effect for the whole body. The calculations are considerable in number and, though more tedious than difficult, should be' entrusted to an experienced calculator. Considerable facility in qualitative interpretation can be acquired by the geophysicist from experience and from a thorough study of the types of gradient and differential curvature anomalies produced by the dif-ferent types of possible structural situations. How-ever, semi-quantitative calculations' of the probable structure bring out many relations that are not evident in a simple inspection of torsion balance results ; it throws out as impossible or improbable certain of the alternative structural possibilities that may seem equally probable under simple inspection of the results; it will determine more accurately the position of the crest of the structure; and reduce considerably the un-certainty in the interpretation and it is necessary to intelligent interpretations. The calculation of such cross-sections consists of a trial-and-error calculation of a body that will give gradient and differential curvature effects as closely as possible the same as those observed. From his knowledge of the gradient and differential curvature produced by different types of bodies, the geophysicist sketches a tentative cross-section of the structure as indicated-to him-by the observed results of the torsion balance survey, and the calculator then splits the struc-ture into blocks, and calculates the gradient and differ-ential curvature block by block. If, as rather usual, the calculated .gradient and differential curvature pro-files diverge considerably from, the respective observed ones, it is necessary to add and subtract blocks from the cross-section until a close agreement is obtained .between the calculated and observed profiles. The com-plete calculations have to be gone through for each block that is added or subtracted.

Jan 9, 1928

By Frank W. Bowdish, T. M. Plouf

The purpose of this writing is to make available additional data, not previously published, on the zeta potential at various pH values of chrysocolla from the Inspiration mine, Arizona. Much research has been performed on chrysocolla, its physical properties, and its flotation, the results of which have not yielded a commercially acceptable flotation process for its recovery. The present data were collected and are presented to further advance chrysocolla research. Experimental For this investigation a carefully prepared sample of chrysocolla was used. This sample was obtained by crushing specimens from the Inspiration mine and picking out by hand the solid blue particles at -3+8 mesh, by grinding these to 10 mesh and repicking the +28 mesh sizes, by cleaning this product using magnetic separation, and by grinding and screening the material into fractions for final magnetic treatment on a Frantz Isodynamic Separator. All testing was done on the -100+150 mesh fraction. A chemical analysis was made on a portion of this fraction which was washed in dis-

Jan 1, 1974

By J. B. Goddard

The discovery of rhenium on the ion exchange resin used at the uraniun in-situ leach operations at Palangana, TX, led to a laborabory study of possible recovery methods. Rhenium was present in small amounts in the ammonium carbonate leach liquors as the perrhenate anion, ReO4-. It concentrated on the anion exchange resin, which was a factor of 10 more selective for rhenium than for uranium. Various elution systems were investigated for stripping the rhenium from the columns after the uranium had been eluted with chloride or nitrate solutions. Although the per-chlorate ion was most efficient on a molar basis, nitrate ion combined the benefits of efficiency and low cost. A 3N or stronger concentration of nitrate containing up to 0. 5N H + was found to be the system of choice. A rhenium sulfide concentrate containing up to 14010 Re was obtained from these effluents by hydrogen sulfide precipitation. Preliminary experiments were run to produce rhenium metal powder by oxidation of the concentrate to NH4ReO4 followed by hydrogen reduction at elevated temperature.

Jan 1, 1984