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By Thomas O. Ziebold, Robert E. Ogilvie

Experimental analysis of diffusion samples covering the entire Cu-Ag-Au system at 725°C has been carried out. Experimental coefficients are computed at twenty-eight points in the lermary system. It is found that the direct coefficienl for copper is nearly independent of the silver, content for 1ow-silver alloys and that the cross coefficient for silver correlates with the ther-nzodynatnic properlies. This lalter observalion leads to the conclusion that the mobililies of copper and gold are nearly equal. Thermodynarmic actiuilies for Cu-Ag-Au were computed from binary data and adjusted to be consistent with neasured tie lines across the two-phase region which extends into the ternary diagram at 725°C. Application of these therknodynarnic calculaliorls to the dijftcsion data terifies the Onsager reciprocal relations to the extent that experimental uncertainlies will allow. It is jound that diffusion neav the critical point of the 1200-phase field in the isothermal section at 725°C causes the composition gradients for copper and silver to approach infinity while the direct and cross coeficients become equal. From the standpoint of experimental Procedures, it has been shown that microanalysis of ternary samples may be carried out using a simple expression for the conversion of X-ray zntensily to composilion. The accuracy of' this method has been demonstrated by the analysis of standard alloys and by the reproducibility of composition determinations using differed X-ray lines. DIFFUSION in a ternary alloy system is basically and significantly different from diffusion in binary alloys. When only two elements are present there is just one independent composition variable, and the diffusion profile of composition vs distance across a sample must change monotonically through all solid solutions bracketed by the terminal alloys. If two-phase regions are stable for compositions between the terminal values, these must appear as planar interfaces in the diffused sample, with the composition profile exhibiting sharp discontinuities. Adding a third element may alter this picture completely. Because of the additional degree of freedom in the composition, we may see composition profiles which do not change monotonically through solid-solution ranges, and stable, nonplanar phase interfaces. Even though two-phase regions may lie between the terminal compositions of a diffusion sample on the constitution diagram, they will not necessarily appear in the diffusion profiles. In binary diffusion only one coefficient is needed to describe the interdiffusion process. From Fick's law this coefficient relates the diffusive flux of one component to its own composition gradient. In ternary diffusion we must allow for cross interaction between the two independent species. By a linear extension of Fick's law we introduce "cross" or "off-diagonal" diffusion coefficients which relate the flux of one component to the composition gradient of the other independent constituent. Thus, we require four interdiffusion coefficients to describe the transport process in a ternary system. In its most general form,1,2 the rate equation for mass transport by isothermal diffusion in a system of s components states that the diffusive flux of component i, Ji, is a linear summation of all driving forces, Xk, each force being multiplied by an appropriate compliance coefficient:

Jan 1, 1968

By W. P. Haynes

No wildcat operations are recorded from France during the past year, and no new discoveries have been made. In northern Africa, in Morocco, some prospecting continued in the Gharb and Tselfat regions. Only very small production or shows were found. At the close of the year one cable-tool well (depth 400 meters) was drilling in the Tselfat district, and one rotary well in the Gharb. In Tunisia one well was drilling at Sloughia. Refinery building has been active under the new petroleum law, no less than six plants now being under construction. At Pechelbronn, it is estimated 130 wells were drilled, of which 73 wells, or 56 per cent, were productive. Total drilling was 45,000 m. One new Jurassic horizon was discovered. In the mining area approximately 17,500 m. of new gallery were driven. Production at Pechelbronn for the first nine months was as follows: From wells, 233,013 bbl.; from mines, 164,815 bb1.—a total estimated production for the year of 532,000 bbl. Production at Gabian was 3780 bbl. for the year. In Algeria production from Tliouanet was small, being estimated at 6510 bbl. This production is from Helvetian sands (Miocene) around a salt plug. Italy Production for the year was 211,500 bbl., an increase of 62 per cent over that of last year. Drilling to the extent of 97,000 ft. was done mainly by the A. G. I. P., the government company in the Province of Emilia. More locations are being tested in this area, where geophysical results have shown indications of buried uplifts. Oil has been encountered on two of these structures, at Fontevivo and Podenzano, but the wells have given trouble with salt water. The chief producer is the Societa Petrolifera Italiana at Salsomaggiore and Valezza. The production is from sand lenses at relatively shallow depths. New concessions of 2000 hectares were granted at several points in the Po Valley, and geophysical work is being carried on. The A. G. I. P. is working on a five-year program of exploration to test new areas.

Jan 1, 1933

By Wm. J. Wright

RECORDS of crude oil in India date back for nearly 100 years, and modest attempts were made to develop the oilfields of Assam about 75 years ago. We have no record of production until 1892 when the fields near Digboi, Assam, yielded about 700 bbl. Since that time, the production of the Digboi fields has increased slowly, but steadily, and new fields have been opened at Badarpur, in Assam, and Khaur, in the Punjab, until the production in India in 1918 was about 293,700 bbl. and the possible production at the present time is approximately 300,000 bbl. per year. In the meantime, the English oil companies in India have been slowly adding to their holdings until they have taken up practically all of the promising territory that is readily accessible, and only about one-tenth of their properties has been touched by the drill. All the producing oilfields of India, and as far as we know all the prospective fields, are confined to areas underlain by rocks of Tertiary age. These rocks consist of more than 20,000 ft. of dark sandstones and shales, with the Nummulitic (Eocene) limestone at the base. In parts of Assam, the lower measures contain economic deposits of bituminous coal. In the Punjab, the upper part contains thick beds of conglomerate. Visible organic remains are rare; except in the limestone and the coal measures. In general, the hardness of the measures increases from top to bottom, but there is an alternation of relatively hard and soft beds throughout the whole series. The rocks are everywhere folded and, in some instances, severely faulted. The crests of eroded anticlines usually stand up as ranges of hills in which the individual ridges are underlain by the relatively' hard beds. Thus structural features are suggested and often clearly defined on the topographic maps.

Jan 3, 1924

By Research Staff ? Verde Copper Mines

FLOTATION is now commonly practiced in alkaline ore pulps, yet little is known regarding the action of the alkaline solutions on the ore particles beyond the fact that films of oxidized material form. We wish to chronicle our discovery of the presence of soluble reducing agents in alkaline ore pulps of the United Verde, and present some data on lime consumption. During the grinding and flotation of a pyritic ore containing small amounts of ferrous sulfate and other soluble salts, an excess of lime was added to precipitate the salts, and filtered samples of the solution were titrated with standard permanganate solution. Even in pulps of high causticity an appreciable permanganate titration was always obtained, in spite of the fact that the solutions were shown to contain little iron. Investigation of the cause brought about the discovery of several previously unsuspected compounds in flotation pulps made from pyritic ore. Not only the reducing agents present had to be identified, but also the amount of dissolved oxygen, and a survey was finally made of the free oxygen content and reducing agents of the mill pulp in the concentrating mill at Clarkdale. A great many compounds might form, caused by oxidation of pyrite or other metal sulfides or by reaction between a lime solution and pyrite. The most probable compounds considered were calcium sulfides; polysul-fides, thiosulfates, and polythionates. Later it was discovered in the literature that in alkaline pulp polythionates do not exist and if introduced. are decomposed into sulfites and thiosulfates.1 Any precipitated sulfur is changed by alkali into thiosulfate and polysulfide. Sulfites and sulfides react to form thiosulfate, so that in the end it is possible to have in an alkaline solution only thiosulfate and an excess either of sulfide or sulfite. Confirmatory tests were made and it was finally established that the alkaline mill pulps made from the United Verde ore contained

Jan 1, 1929

By L. C. Brown, J. S. Kirkaldy

Measurements have been made of carbon diffuswn in the five ternary austenites Fe-C-Si, Fe-C-Ni, Fe-C-Co, Fe-C-Mn, and Fe-C-Cr in which the carbon (component 1) diffuses through interstitial sites and the ternary addition (component 2) diffuses substitutionally. Values of the diffusion-coefficient ratio, D12/D11 were determined for each system with finite couples using the transient equilibrium method. The effect of temperature and of concentrations of both the carbon and substitutional component upon D12/D was examined and was found to agree with the theoretical predictions. It is concluded that within an experimental uncertainty of 10 to 15 pct, it is possible to calculate the ratio D12/D11 from purely thermody-namic data. Difficulties of measuring the other off-diagonal coefficient, 4,, are discussed. Any quantitative attack on the fundamentals of the hardenability problem in steel must begin with the multicomponent diffusion formalism and with the accumulation of data pertaining thereto. In a recent paper Kirkaldy and purdy 1 employed the formalism derived from irreversible thermodynamics to treat the problem of diffusion in ternary austenites. In the latter solutions, carbon diffuses through interstitial sites and the substitutional component diffuses through the lattice. Examples were given of diffusion in the systems Fe-Mn-C and Fe-Si-C. In the present paper, we present new results on and discuss their agreement with the thermody-namic theory. Since the theory has been slightly modified from the original presentation of Kirkaldy and Purdy, their results on Fe-Si-C and Fe-Mn-C have been recalculated and are presented here for completeness. The flux of the interstitial component with respect to a fixed lattice framework can be written as a linear expansion in the independent concentration gradients, where X1 and X2 are the independent thermody-namic forces in the lattice fixed frame of reference. These forces can be obtained from the general statement for forces in a volume fixed frame2 if the partial molar volume of carbon atoms is set equal to zero and that of the substitutional component 2 is set equal to unity, viz where the are the chemical potentials and the N's are mole fractions. Introducing into [3] and [4] the function If, as suggested by statistical arguments, the off-diagonal interaction L12 is sufficiently small, [6] reduces to i.e., the coefficient ratio becomes purely thermo-dynamic. The activity of components 1 and 2 in a dilute ternary system (standard state at infinite dilution) may be represented by the expansion3

Jan 1, 1964

By Rossiter W. Raymond

In the course of this address, President Raymond referred to the law, said to have been discovered at the French works of Terrenoire, that the amount of phosphorus may be increased without injury to steel, if the amount of carbon be proportionately decreased. The works named have been for more than a year, it is said, manufacturing in the open hearth, by the Martin process, steel rails containing as high as 0.35 per cent. of phosphorus, with about 0.15 per cent. of carbon, which were not found inferior to Bessemer rails. It is not claimed by the manager of the works that phosphorus is an ingredient to be preferred, or purposely introduced; but only that materials containing it (such as old iron rails, etc.), can be succesfully employed. Other parties have apparently a higher opinion still of the new manipulation, and are prepared to claim for " phosphorus steel" superior qualities. Mr. I. Lowthian Bell alluded to the subject in his recent address as President of the British Iron and Steel Institute, but without expressing a positive opinion. After pointing out that the commercial value of the process turned on the cheap manufacture of ferro-manganese, by means of which only could the necessary amount of manganese be introduced into the Martin bath, without increasing its contents of carbon, Mr. Raymond proceeded to say that the principle alleged to have been discovered at Terrenoire was already known years ago, in this country, at least. Not only had steel been manufactured here, containing high percentages of phosphorus, coupled with low percentages of carbon, and suitable for use in rails, boiler-plates, etc., but the reason of its surprising qualities had been distinctly surmised, if not widely proclaimed. The following analyses and extracts from private letters prove these assertions. Some of them assert a similar principle in .the case of wrought iron; but the analyses, and the remarks based upon them, have reference solely to the steel manufactured under the superintendence of Mr. Slade, at the works of the New Jersey Steel and Iron Company in Trenton.

By F. R. Ingalsbe

THE proposed revision of the mining law as set forth in the Arentz Bill, now before Congress, is centered about the pretty commonly acknowledged f act that the present law is outlawed both by the large mining companies and the United States Land Office. By common agreement, the law of the apex is non-opera¬tive as between adjacent properties in many instances, and this practice is becoming more common. - If this is a fact, there is no escape from the conclusion that the law is antiquated and should be revised to meet modern conditions more equitable. The thing to be considered seriously is in what direction and to what extent the laws should be changed. Before deciding this, it is logical to inquire in what particulars the present law is troublesome or useless. This was all threshed out by the committee of the Bureau of Mines that worked out the proposed bill, but their testimony was not placed before the public, so far as 1 am aware. Most mine managers and engineers connected with producing properties are a unit in agreeing that the law as applied to the underground extension of orebodies, that is, the "law of the apex," as it is called, is the source of more litigation and expense than any other phase of the law, or perhaps than all other phases combined. This being true, it seems that this part of the law should be changed. Another phase which is troublesome and will continue to be so long as there is unpatented mineral land on the Public Domain, is the discovery requirement. The present law requires that a dis¬covery be made before a claim is staked and the courts certainly agree that such must be the case before patent issues.

Jan 7, 1922

By C. E. Lesher

THE Disco* process for the production of low temperature coke and its immediate predecessor, the Wisner or Carbocite process have been described in the voluminous literature of low temperature carbonization.1 This paper will describe the development of the process from the first attempt at commercial operation by the American Gas and Electric Co. at Philo, Ohio, Yn the 1920's to the successful operation in 1949 by the Disco Co., a division of the Pittsburgh Consolidation Coal Co., of the 1000-ton per day Disco plant near Pittsburgh, see Figs. 1-2. In the 1924 coal industry depression following the hectic post World War I expansion, the northern Appalachian, unionized bituminous coal fields were affected first and foremost, and Western Pennsylvania as hard as any. Competitive market pressure was heaviest on the lower grades of steam coals, notably the from the Panhandle district where ash and sulphur are inherently higher than in the same Pittsburgh coal bed to the east along the rivers. The firm structure of Panhandle coal while favoring the prepared sizes, depressed the usefulness and value of the finer sizes. Panhandle slack and nut slack were marketed with difficulty at consistent, and at times considerable, loss. Many solutions were suggested, and the Pittsburgh Coal Co. investigated all. Lower delivered prices through lower mine costs and more advantageous freight rates were obvious goals, but equally obvious were the difficulties of self attainment of either in any substantial measure. Selling Btu's in pipes was abandoned as an idea after a thorough study of the economics of distribution of what was then, and is even now, the only developed continuous process of complete gasification of bituminous coal-producer gas. Although the coal company purchased huge blocks of electric power, it sold not a car of coal to the central power stations. Public utilities controlled the markets for electric current, and it was found that no matter at how low a cost current might be put on the bus bars by the coal company, distribution to its widely scattered coal mines made such an enterprise practically impossible. Consolidation of underground operations and a huge modernization program of mining operations in the 1920's were but preparation for the introduction of mechanical cleaning of the coal for market, particularly the smaller sizes of steam, gas, and by-

Jan 1, 1953

By C. E. Lesher

THE Disco* process for the production of low temperature coke and its immediate predecessor, the Wisner or Carbocite process have been described in the voluminous literature of low temperature carbonization.1 This paper will describe the development of the process from the first attempt at commercial operation by the American Gas and Electric Co. at Philo, Ohio, Yn the 1920's to the successful operation in 1949 by the Disco Co., a division of the Pittsburgh Consolidation Coal Co., of the 1000-ton per day Disco plant near Pittsburgh, see Figs. 1-2. In the 1924 coal industry depression following the hectic post World War I expansion, the northern Appalachian, unionized bituminous coal fields were affected first and foremost, and Western Pennsylvania as hard as any. Competitive market pressure was heaviest on the lower grades of steam coals, notably the from the Panhandle district where ash and sulphur are inherently higher than in the same Pittsburgh coal bed to the east along the rivers. The firm structure of Panhandle coal while favoring the prepared sizes, depressed the usefulness and value of the finer sizes. Panhandle slack and nut slack were marketed with difficulty at consistent, and at times considerable, loss. Many solutions were suggested, and the Pittsburgh Coal Co. investigated all. Lower delivered prices through lower mine costs and more advantageous freight rates were obvious goals, but equally obvious were the difficulties of self attainment of either in any substantial measure. Selling Btu's in pipes was abandoned as an idea after a thorough study of the economics of distribution of what was then, and is even now, the only developed continuous process of complete gasification of bituminous coal-producer gas. Although the coal company purchased huge blocks of electric power, it sold not a car of coal to the central power stations. Public utilities controlled the markets for electric current, and it was found that no matter at how low a cost current might be put on the bus bars by the coal company, distribution to its widely scattered coal mines made such an enterprise practically impossible. Consolidation of underground operations and a huge modernization program of mining operations in the 1920's were but preparation for the introduction of mechanical cleaning of the coal for market, particularly the smaller sizes of steam, gas, and by-

Jan 1, 1953

By Gearge C. Wallick

This paper describes experimental procedures for the calibration of capillary tubes to be employed as comparison standards in gas flow-rate measurements and considers several types of flow which were observed in the calibration of seven capillaries of varying diameter. It is shown that under certain experimental conditions deviations from Poiseuille flow are observed which may not be attributed to turbulence, and that this flow behavior may be described empirically by introducing the classical kinetic energy correction into the Poiseuille equation. INTRODUCTION Techniques have been developed for the measurement of the volume rate of flow of nitrogen through glass capillary tubes as a function both of the differential pressure applied and of the absolute gas pressure. Capillary tubes thus calibrated are frequently used to determine the rate of gas flow through a porous sample in the measurement of slip-corrected permeability. The purpose of this note is to describe the calibration procedure and to discuss some observed deviations from the ideal flow behavior predicted by the Poiseuille equation. EXPERIMENTAL PROCEDURE The volume flow rate of nitrogen as a function of the differential pressure was determined experimentally for a series of seven glass capillary tubes of varying diameter. As is shown in Table 1, the capillary radii in the series ranged from 0.004 cm for K1 to 0.07 cm for K7. The capillary tubes were cut from capillary tubing purchased on special order from several manufacturers and the bore radii were determined by microscopic measurement. The gas volume flow rate was measured for each capillary tube at a series of differential pressures in the range from 0 to 3 cm of mercury and at average absolute pressures of 1.0, 2.5, 4.0, and 6.0 atm. Experimental Procedure for Small Capillaries A schematic diagram of the apparatus used to calibrate the three smallest capillaries, Kl, K2, and K3, is shown in Fig. 1. By means of a standard Ruska Instrument Corp. volumetric pump (equipped with a synchronous motor drive, two stages of gear reduction, and a quick-change lathe gear box), nitrogen was displaced by mercury from a metal cell immersed in a constant-temperature bath. The pump, the line to the cell, and a part of the cell were filled with mercury. As mercury was forced into the cell, it displaced nitrogen which passed through the capillary tube being calibrated and into a large container with a volume of approximately 30 liters. Since the volume of this container was very large compared to the total volume change of the gas resulting from the action of the displacement pump, the absolute pressure of the system was essentially constant throughout any one run. Prior to any determination this pressure could be set at any desired level by means of an auxiliary nitrogen cylinder. The differential pressure across the capillary was measured with a Meriam Red Oil manometer and recorded together with the corresponding pump displacement rate which was equal to the gas flow rate. By repeating this process for a series of different displacement rates at each of the absolute pressures of interest, the data necessary for plotting the calibration curves for capillaries K1, K2, and K3 were obtained. All calibration measurements were made in a constant temperature room to minimize errors due to temperature fluctuations. In each run. the flow was maintained until equilibrium was established. Experimental Procedures for Large Capillaries The flow rates through Capillaries K4, K5, K6, and K7 required to obtain the pressure drops desired were larger than could be obtained from available constant displacement pumps, and it was thus necessary to employ an alternative calibration procedure. The arrangement of apparatus used in calibrating these capillaries at an average pressure of one atmosphere is shown in Fig. 2. Each capillary was calibrated by flowing nitrogen through the capillary and recording the differential pressure as a function of the flow rate. 'The differential pressure was measured with a Meriam Red Oil manometer and the flow rate was determined by collecting the effluent gas over water at constant pressure and recording the increase in volume per unit time after an equilibrium had been established. Appropriate corrections were made for the

Jan 1, 1953

By R. A. Wagstaff

MANY changes in equipment have had to be made to handle the flotation products at the blast furnace, and these changes have meant an expenditure of considerable money, which has not been compensated by an increase in smelting tonnage. To date, very few new lead mines have been developed, so that the help derived by the innovation of flotation has been directed to old producing properties, where the ratio of concentration is greater now than when gravity concentration was in effect. In some smelting plants there has been an abandonment of complete units due to the introduction of flotation. FLOTATION PRODUCTS DIFFICULT TO HANDLE The physical characteristics of the flotation product do not make for economic handling for lead blast-furnace work, either mechanically or metallurgically. The millman or miner do not know what trials and tribulations they have passed on to the smelterman. To the smelterman it is "the everchanging flotation," for little does he know what new reagent will be perfected tomorrow that may completely change the grade and physical characteristics of the product. Even the mining companies who have complete units of mining, milling and smelting have had a hard time to reconcile themselves to the fact that the unit cost per ton of ore smelted must go up with the increase of flotation product on the blast-furnace charge. The "smelterman's burden," for that is what flotation has been for the last few years, has not caused the smelter operator to lag or fall down, but has spurred him on with new zeal. The physical properties of the flotation products are as follows: (1) High moisture content; (2) mucky nature of product; (3) fineness of product, and (4) high metal content. NEW MECHANICAL DEVICES FOR HANDLING FURNACE PRODUCT These characteristics have caused the use of many new mechanical devices in smelting practice, for example: New transportation equipment, such as solid-bottom cars, is required; unloading equipment and sampling

Jan 1, 1928

By AIME AIME

OUT of the fabulous iron ranges of Michigan?s Upper Peninsula since Pearl Harbor have come go to the steel mills to become tanks, guns, ships, and other weapons for a United Nations' victory. But the contributions to the war effort, as far as Michigan's iron country is concerned, do not stop there. The same men who mine iron ore deep inside the earth also are "mining" on top of the ground, gleaning a harvest of scrap iron and steel that is writing a big chapter in the War Production Board's salvage program. At virtually every mine over an area of a hundred square miles, everyone from the top mine official and straw boss to the man in the dippings is scrap conscious. They know the importance of the ore they mine but they are equally familiar with the importance of iron and steel scrap in war production. The successful job they are doing in salvage is a tribute to the entire Upper Michigan mining industry and to the man who marshaled them into action-John M. Bush, chief of the land department for the Cleveland- Cliffs Iron Co. at Negaunee, and for ten years an A.I.M.E. member. Also, this job should be an inspiration to 611 mining. metallurgical, and petroleum communities as to the latent possibilities of organized scrap recovery.

Jan 1, 1943

By P. K. Guerrero, N. Arbiter

The correlation of power consumed by a tumbling mill with the dimensions, speed, and load has been attempted by three principal methods. One of these, the torque formula, has been reviewed critically elsewhere.' This approach, while analytical, disregards the individual motion and speed of the tumbling bodies and assumes that the gross geometry of the entire load is sufficient to establish the power requirement. A more general approach, using dimensional analysis, has been applied in this laboratory by the present authors1'1, and more recently by Rose.3 This disregards the internal conditions within the mill entirely and in effect is an empirical procedure for correlating data. Finally, the complete analysis of tumbling mill dynamics as first made by Davis' attempts to develop the power requirement from individual ball and rod paths and velocities. Although Davis' result is applicable only at a single speed for a given size and load it could be useful, since his optimum speed is at the upper limits of conventional tumbling mill practice. Where power values predicted by the Davis equation were compared with actual mill requirements, they were found too low for small mills and much too high for the largest mills. This suggested that the agreement with actual intermediate range requirements might be fortuitous, and the development of the equation was examined critically. The probable source of error was found to lie in an erroneous assumption made by Davis in converting the energy of ball or rod motion to power. With the same approach, but with different assumptions, a modified equation has been obtained which predicts results that are usually consistently high. This is to be expected, since it is assumed that there is no slip between load and shell and no interference among tumbling bodies. Both these effects should account for the difference. Development of Equation: When a cylindrical shell charged with a substantial weight of rods or balls is slowly rotated about a horizontal axis, the load surface first assumes an inclination that gradually increases to a maximum. Continued rotation results in failure within the load, characterized by a sliding of the top layers down the slope and a reduction in the angle of inclination. Further rotation again increases the angle, and the cycle repeats. If the speed is increased, there is continuous load failure and build-up and a continuous stream of rods or balls descends over the upcoming mass, which moves in circular arcs. At higher speeds the up-

Jan 1, 1961

By Chung Yu Wang

DURING the time I was in charge, of this mine, from 1914 to 1915, I had occasion to read the interesting papers by T. T. Read and C. M. Weld about these deposits, to find how far their observations corroborated mine. To quote from the paper on "The Mineral Production and Resources of China" by T. T. Read:' "The iron ores at Tayeh lie along the contact between a marble and an intrusive body of a dark gray syenitic rock. * * * * At one place it is slightly magnetic, apparently having been partly reduced to the magnetic oxide by the action of reducing solutions, which have deposited small amounts of copper and iron sulphides along the foot wall." To quote from the paper on "The Tayeh Iron Ore Deposits"2 by C. M. Weld: "I find the orebodies described as occurring along an approximately E-W contact between horn-blende-granite and limestone. * * * * The granite is a granitoid rock consisting essentially of quartz, potash-feldspar and hornblende." These quotations show the differences of opinion entertained by two observers. My own study of these interesting deposits has been intermittent amid the manifold duties devolving upon a superintendent. General Description of the Deposits The deposits are situated to the west of the Yangtse River, being con¬nected with the river by a standard-gage railroad of 56 li (16.16 miles, 26 km.) in length, as shown in Fig. 1. The general topography of the region is of mature age, showing broad valleys with sluggishly meandering streams. These deposits are worked as two mines, named the Tieh Shan Mining Department and the Teh Tao Wan Mining Department; the former consisting of three orebodies more or less connected, named Tieh Man Kan, Sha Mau Tze and Lung Tung, and the latter consisting of Chang Pei Shan, Sze Tze Shan, Ta Shih Men, Yeh Chih Ping and Tsin Shan, also more or less connected, as shown in Fig. 2.

Jan 3, 1917

By O. M. McRae. Discussion by R. W. Jones

R. W. Jones (Senior Exploration Geologist, Standard Oil Co. of California, Box 250, Seattle, Wash.) -Mr. McRae6 and his colleagues are to be congratulated for providing a more coherent structural synthesis of the complex structure in the Courtland-Gleeson area, Cochise County, Arizona, than the "gigantic thrust breccia" concept of Gilluly. 4 However, a few problems of interpretation remain. It is the intent of this note to point out some of these problems, and, drawing on my own work in the area as well as the work of McRae6 and Gilluly, 4 to suggest some interpretations which differ from those previously published. GRAVITY SLIDES In an unpublished manuscript (Jones5) I previously argued that most of the complex structures in the Courtland-Gleeson area can be most reasonably interpreted in terms of gravity sliding caused by uplift and eastward tilting of Jurassic intrusives and associated Paleozoic rocks. Although the field work and drill hole data described by McRae6 provided excellent documentation for two important gravity slides, McRae6 interpreted the basic structure in the Courtland-Gleeson area in terms of major eastward directed thrusting. I continue to disbelieve the

Jan 1, 1967

By R. W. Hertzberg, F. D. Lemkey, J. A. Ford

The effect oj unidirectional solidification upon the microstructural, crystallographic and mechanical characteristics of high -purity A1-A13Ni eutectic a1loy specimens has been investigated. varying the growth rate caused the morphology of the Al3Ni phase to gradually change from platelets to rods. In addition, the effect of increasing the rate of planar liquid-solid interlace movement is to decrease the Al3Ni rod diameter and inter-rod spacing. The platelets and rods grow approxinlately parallel to each other and are aligned in a faulted substructure. A single unique crystallographic relationship hetween the A1 and ASNi phases was found and may he descrihed as : interface {001} Al3Ni {331} Al and growth direction <010>Al3Ni || <110> Al The platelet interlace and the aligned rows of rods are both uniquely defined by the above statements. Alignment of the Al3Ni phase by unidirectional solidification has given rise to a threefold increase in strength over that exhibited by specimens with an as-cast microstructure. These results illustrate the possible use of this eutectic alloy as a zohisker -reinforced structure. It has been demonstrated by Winegard et al.,1 Kraft and Albrighht,2 Chilton and winegard,3 Chad-wick,4 Yue,5 Tiller,6 and others that a planar liquid-solid interface may be established in binary eutectic alloys by proper control of heat flow during the solidification process. The unidirectional movement of such an interface results in a eutectic mi-crostructure consisting of an essentially parallel array of the two phases over an entire ingot. Two dominant phase micromorphologies have been produced using this technique: that of substantially parallel alternating lamellae of each phase or long thin parallel rods of one phase imbedded in a continuous matrix of the other phase. While not all eutectics can be controlled in this manner, it has been shown that a "normal" eutectic may, under properly controlled conditions of purity, liquid and solid thermal gradients, and solidification rate, be forced to solidify with essentially parallel phase particles. Kraft and Albright2 have demonstrated that, when the growth rate is too rapid or when the thermal gradient in the liquid at the growing interface is too low, a layer of constitutionally supercooled liquid, formed by impurity build-up, will stabilize a cellular rather than a planar interface. The unidirectional movement of the cellular interface forms the macrostructure of eutectic colonies.7 Chilton,3 Chadwick,4 and Tiller,&apos; studying eutectics of zone-refined Pb-Sn, A1-CuAl2, Zn-Sn, and Cd-Zn systems, noted that in the absence of impurities a planar interface is stabilized even when rapidly solidified. Although it is generally agreed that impurities break down a planar interface to form the eutectic-colony macrostructure, at present the origin of the varying micromorphologies (i.c., plates or rods) in a given normal eutectic alloy is not completely understood. Tiller8 has predicted that the micromor-phology produced may be dependent on solidification rate (i.e., at fast rates a rodlike structure is preferred whereas at slow rates a lamellar structure should form), and also suggested that rod formation may be favored at large phase-volume ratios. yue5 has experimentally verified Tiller&apos;s prediction in the eutectic Mg-Mg17Al12 by observing a lamellae-to-rod transition with increasing growth rate where the phase-volume ratio was approximately 2.3:1. However, Hunt and chilton9 more recently unidirec-tionally solidified over a wide range of growth velocities six different eutectic systems with phase-volume ratios between 12:l and 2.7:1 and observed no lamellae-to-rod transition. chadwickl0 has proposed that the change in micromorphology in some eutectic alloys is due entirely to the presence of impurities and further states that the lamellar structure is the characteristic structure of pure eutectic alloys even when the phase-volume ratio is as great as 12:l. Kraft11,12 has shown that the parallel lamellae in certain eutectic alloys assume a unique crystallographic relationship during unidirectional growth. This preferred crystallography may be developed

Jan 1, 1965

[ ] Granville S. Borden (Mining Taxation, P. 1049) has written two other published articles on the subject, Taxation and Mineral Resources, and An Income Tax Program for Mineral Producers. Both articles appeared in Mining Engineering. He is presently employed by Standard Oil Co. of California as a special tax counsel. He holds an LL. B and an LL. M from George Washington University and a Bachelor of Science in Mining from the University of California. He has been chairman of the Taxation Committee of the Minerals Economics div. of the AIME. Borden fishes, plays golf, prospects, and performs mineral analysis as hobbies. [ ] Charles C. Towle (co-author, Uranium Deposits of the Grants District, New Mexico, P. 1037) graduated from the Colorado School of Mines with a degree in Geological Engineering. He was a member of Sigma Nu; Theta Tau, an honorary professional society; Blue Key, honorary social society; the glee club and quartet, and a member of the student council. He has been a mucker, driller, flotation operator and mill shift boss for the Clear Creek-Gilpin Co., Idaho Springs, Colo.; Geologist, chief engineer, and chief geologist for Patino Mines & Enterprises Consolidated, Inc., Bolivia; appraisal engineer and part-time geology student, Denver; office geologist for Geology Dept., special Engineering div., Sea Level Canal Studies, Panama Canal; and geologist, div. of Raw Materials, USAEC, Grand Junction, Colo. He is currently chief of the Denver Exploration Branch, div. of Raw Materials, USAEC, Denver. Towle was at one time a tournament golfer, playing three and four times a week. While working in South America he played in numerous tournaments. Today, although playing only occa sionally, he shoots in the low eighties.

Jan 1, 1952

By Axel Hultgren, B. Herrlander

THE original aim of the present investigation was to study the mechanism of cracking on hot-deforming red-short steels. During the microscopical examination of hot-deformed soft steels attention was directed to various patterns of so-called veining in the ferrite, as related to variations in the deformation procedure and the heat-treatment of the steels. Later, a hot-short steel of higher carbon content was also studied. Historical Storey1 suggested in 1914 that veining developed during the gamma-alpha transformation from the growing together of several alpha nuclei within the same gamma grain. Rawdon and Berglund2 found that in soft steel, forged somewhat below A3, the ferrite showed profuse veining, while usually there was very little veining after forging at very high temperatures. They emphasized the similarity between the pattern of veining formed by deformation about 600°C and that of slip lines formed by deformation at room temperature. They also suggested a relation between the gamma-alpha transformation and veining. They became convinced from etching and from the slip-line pattern in cold-deformed material, that the orientation within any ferrite grain showing veining was uniform. In recrystallized alpha grains veining was absent. Veining did not appear materially to affect the properties of ferrite. Independent of veining, continuous networks, attributed to preexisting delta and gamma grain boundaries were sometimes found, the former only in cast steel. Those networks were usually connected with small inclusions. Ammermann and Kornfeld3 confirmed that recrystallized ferrite grains showed no veining. In soft steel annealed between At and A3 there was veining only in the ferrite grains formed during cooling. Electrolytic iron deformed at 880° was free from veining. Bannister and Jones4 considered veining in ferrite to be a manifestation of microscopical and submicroscopical inclusions. Northcott,5,6 in studies on veining in steel and other metals and alloys, attributed veining to oxide inclusions. It could generally be removed by annealing in hydrogen, a suggestion earlier made by Rawdon and Berglund. Tritton (discussion in ref. 5) emphasized the importance of perfect polishing for bringing out veining by etching, and thought the veins or subboundaries were produced during the gamma-alpha transformation, when it was rapid, as a result of the volume change and contraction during cooling.

Jan 1, 1946

By Lucien Eaton

THE accuracy with which detachable bits can be sharpened and gauged by grinding has made possible refinements in design that cannot be attained by forging. This applies particularly to gauging, where accuracy is of the greatest importance. Gauge changes of 1/32 in., and even 1/16 in., are now feasible, whereas 1/16 -in. changes are about the limit in accuracy for forged bits. These small changes in gauge are feasible, however, only with certain fundamental principles of design. Within reasonable limits the depth to which a hole can be drilled is dependent primarily upon the loss in gauge, or diameter, of the bit. In drilling there is always a certain amount of " overdrilling "-the bouncing of the bit in the hole and its rotation wear away the walls-so that the actual diameter of the hole is greater than the diameter of the bit. The amount of this overdrilling depends upon the kind of rock being drilled, and is sometimes sufficient to permit the use of the same diameter of bit for the full depth of the hole. If, for instance, a 1 ¾ -in. diameter bit overdrills 1/32 in. in diameter, and loses 1/64 in. in gauge in drilling 2 ft. of hole, the bottom of the hole is still 1/64 in. larger than the original diameter of the bit, and a new 1 3/4-in. bit can be used to drill the next 2 ft. If, however, the overdrill is less than the loss in gauge, the next bit must be of smaller diameter. The first requisite in reducing loss of gauge in drilling is to have the points and corners of the wings of the bit cut circles of the same diameter, thus producing a reaming surface with continuous bearing on the wall of the hole. The greater the reaming surface, the less the gauge loss that is to be expected. If the reaming surface, however, is too large, it may impede the rotation of the bit through excessive friction. This principle was probably first recognized in the design of the Carr bit (Fig. 1)) a bit with a single cutting edge of wide angle, a definite reaming edge, and a large center hole. The same idea was followed in designing the double-taper cross bits, which are now standard almost everywhere Fig. 2 illustrates a typical double-taper cross bit. The taper from the point of the wing A to a little behind the corner B is 5° and from

Jan 1, 1939

By H. E. Rorschach

Activity in the oil and gas fields of Oklahoma was more pronounced in 1935 than in 1934, with 2320 completions, an increase of about 21 per cent. The state produced approximately 185,000,000 bbl. in 1935. Osage County and shallow pools in northeastern Oklahoma showed considerable activity. The assembly of a complete table of the oil fields of the state (Table 1) was not achieved, as many of the early records of operators and pipe line companies are not complete, and data for the older fields will perhaps never be fully tabulated. Table 1 includes all of the new fields and most of the important fields of the State of Oklahoma. Increased Field Activities The discovery of large production in the deep Simpson group in the old Fox field in Carter County in the southern part of the state, the discovery of new producing horizons in the Fitts pool, and the extension of Wilcox production in the "Mansion" area at Oklahoma City were the outstanding developments in Oklahoma in 1935. Wildcatting resulted in the discovery of new pools such as Jesse, Hoyt, Grayson, South Keokuk, Wofford, Britton and Stillwater. The Fitts and Edmond pools were rapidly developed during the year. Fox Pool.—Deep production in southern Oklahoma became a reality in October when the Williams No. 1 well of Carter Oil Co. and others, in the Fox pool, began producing oil at the rate of 10,000 bbl. per day from a depth of 8088 ft. After flowing wild several days, the well was killed after pipe stuck and a difficult fishing job resulted. The job had not been completed at the end of the year 1935. This test, considered one of the most important oil discoveries in the Mid-Continent area, opened the entire South Oklahoma area to a deep exploration campaign for Simpson production and production in the Pennsylvanian series on the south flank of the Arbuckle Mountains.

Jan 1, 1936