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By John F. Blandy

With the Report of Mining Statistics, for the year 1872, there was published a geological map of the United States and Territories. This is, I believe, the only map which represents the geology of Arizona, and is, as far as my observations go, correct. It is, however, on so small a scale as to be of little practical value to the miner. I know of no other maps, even of localities, of this Territory. The topographical maps are also on so small a scale as not even to serve as guides from place to place; the largest, that of Eckhoff and Ricker, being only 30 by 30 inches to represent a territory of 135,000 square miles. For these reasons, it makes it exceedingly difficult to describe the various mining centres in an intelligent manner, and equally so to examine such a hilly country as it is intended to describe in this paper. When I first came into this Territory I soon realized the troubles I had to encounter in trying to form an opinion, or even to get the needed information on the geological contour. I have, therefore, labored as best I could to get a topographical diagram of the section of country represented by the map which accompanies this paper.* The lines run by the Land Department up the valleys of the Aqua Frio, and those west of the Hassayampa, and connected east and west to the north of Prescott, enabled me to inclose correctly the space covered by the Bradshaw and Sierra Prieta mountain groups, but the territory covered by these mountains, and the most difficult part, I have had to fill up as best I could. I have met with such success as to meet the approbation of those most familiar with the country, and, with the map in hand, any one would he able to cross it in any direction. As there has not been a single line of survey made across it, this has been no small undertaking, and I have had to depend upon sights from prominent points with the pocket-compass, or, in the absence of that, to make observations, with watch in hand, and guess as near as possible the meridian direction. Rut one main wagon-road passes through the district, that from Prescott to the Peck mine.

Jan 1, 1883

By T. A. Rickard

We rejoice that the world-war is ended. We are proud of the part played by the English-speaking peoples-all doing equal honor to the traditions they share in common. One of the compensations for the calamity of the past four years is the fact that the Briton and the American, striving together in the cause of human liberty, have learned to understand and to respect each other. The mother country entered the fight resolutely at the beginning, while yet unready to meet the carefully prepared onslaught of the enemy; then the sons from the overseas dominions rallied to the old battle-cry eagerly and effectively; and last, but not least, the stepsons came from across the Atlantic, speaking the same speech, playing the same game, and fighting in the same clean way. It was a great foregathering of those that use the language of Shakespeare and idealize the principles of liberty for which the friends and associates of Shakespeare stood sponsor three centuries ago. At a time like this it is pleasant to dwell upon the fact that the liberal Englishmen who organized the Virginia company were the pioneers of self-government on the American continent. The Virginia Assembly, convoked in 1619, was the first example of a domestic parliament to regulate internal affairs on this side of the Atlantic.2 The Governor of Virginia, Sir Edwin Sandys, had been a pupil of Richard Hooker at Oxford and from that political teacher he and his friends had imbibed the idea of combining civil liberty with constitutional order. To this group of large-minded Englishmen, the American colonists owed their liberal charters and their successive triumphs over the royal prerogative. Let it be noted that the American colonists had to deal with James II and George III, the two smallest minds in the list of British kings. Another historical note more pleasant to record, is the connection between the two principal groups of American settlers. In 1608 when the Pilgrim fathers, William Brewster and John Robinson, led their Separatist congregation to Holland and there prepared the expedition to America, they were assisted by Sandys and the Virginia Council, who were willing to share their privileges with them. When the Pilgrims set sail in 1620 they had the promise, obtained by Sandys from King James, that they should have freedom of worship,

Jan 4, 1919

By C. E. Birchenall, H. M. Schadel

THE purpose of this study was to measure the vapor pressure of silver as the first step in the determination of activities in silver alloys and to test the limitations of the method adopted. In order to work at low pressures, below 2x10-2 mm of mercury, the orifice effusion technique was employed. To shorten the time of collection of silver from the atomic beam, radioactive silver (Ag110) was used as a tracer. The rate of effusion of a monatomic vapor from an "ideal" orifice, where the thickness of the orifice edge is negligible compared with the orifice diameter, can be readily calculated from the kinetic theory of gases, G = vM a p/v2pRT where G is the weight of material effusing from the orifice per unit time; p is the vapor pressure at oven temperature, T; R is the gas constant; M is the molecular weight of the vapor; and a is the orifice area. Consolidating constants and expressing as the weight of material effusing from the orifice in a period of time, t, (5.83)(10-2) (vM) (a) (t) (p)/vT where GT is total weight of monatomic vapor effused (g); M is molecular weight of the effusing tracer vapor; a is orifice area (cm2); t is time of effusion (sec); p is vapor pressure of effusing material (mm of Hg); and T is oven temperature (OK). The vapor effuses from the orifice in a hemispherical pattern, and the intensity of the beam in any direction is given by the cosine distribution law.' Considering this, the weight of effused material can be calculated from the amount of material passing through a circular collimator intersecting the beam. If such a collimator is in a plane parallel to the plane of the orifice and with center on the normal to the orifice center, GT = G?/1-cos2? = G?/sin2? where G? is the weight of effused material passing through the collimator, and 0 is one half the apex angle of the cone defined by the collimator circumference and the orifice center. Reducing eq 3 to the more directly measurable quantities of orifice to collimator distance, d, and collimator diameter, D, the expression becomes,

Jan 1, 1951

By L. D. Jaffe Hollomon, Hollomon John H.

For many steel parts it is desired to obtain the maximum toughness consistent with the strength required by the mechanical design. It is generally recognized that the greatest toughness at any given strength is found in steels having a tempered martensitic structure.' and is virtually independent of the composition of the steel2 (except for carbon). The choice of the composition of a steel for the parts in question should be based, therefore, on hardenability considerations and on manufacturing facility and economy. In a recent paper3 the concept of hardenability was discussed and a somewhat new approach to the problem was suggested. The hardenability was defined in terms of the cooling conditions (speed of cooling) required to avoid the pearlite and the bainite reactions. Since all the alloying elements do not have the same effects on the two reactions, the bainitic and pearl-itic hardenabilities must be considered separately. In order to design a steel for a given part, it is necessary to design a composition that has both sufficient pearlitic and sufficient bainitic hardenability. However, this requirement does not fix the combination of alloying elements to be used; an infinite number of steels would have the required hardenabilities. Other considerations limit the choice. For example, decreasing the carbon content increases the toughness at a given hardness, and for this reason low-carbon steels are often desired. Limitations or requirements of refining, casting, or forming practices often affect the level of some of the alloying elements. Price considerations enter. Frequently, however, it is very desirable to minimize the tendency toward quench-cracking while maintaining the necessary hardenability. This paper is concerned with suggesting a method for choosing compositions that will have the required hardenability together with minimum tendency toward quench-cracking. Quench Cracking Since only the case in which the entire part will transform to martensite in the particular quench employed is being considered, the analysis of the quench-cracking problem is somewhat simplified. Quench-cracking arises from the temperature gradients existing throughout the piece during cooling. Because of these temperature gradients, the contraction arising from the decreasing temperature and the expansion arising from the austenite-martensite reaction do not occur uniformly over the parts, and stresses are set up that tend to cause cracking. The temperature gradients can be reduced by decreasing the severity of quench. This, however, requires that the hardenability be correspondingly increased by increasing the carbon or alloy content. An

Jan 1, 1947

By John D. Meahin

THE use of digital methods for generating crystallo-graphic data is well-established and many programs are now available. Transmission electron microscopy usually requires a knowledge of the electron diffraction pattern which is obtained by plotting a planar section through reciprocal space. With cubic symmetry these sections are very easily produced, but with hexagonal and lower symmetry systems considerably more labor is involved. Johari and Buchanan1 have written a Fortran program for generating standard projections and along similar lines we have produced a short but completely general program for generating any section through reciprocal space. The required inputs are the lattice parameters and angles for the real crystal. The Miller indices of the direction [U, V, W] parallel to the electron beam are then specified and the program will generate the Miller indices of the plane normals perpendicular to [U, V,, W] up to some specified integer. A subroutine can be inserted to test for forbidden reflections if desired. We have used such routines for fct and hcp crystals. As each permitted index is generated it is printed or punched out and no storage arrays are utilized in the computer. The normal diffraction pattern corresponds to the zero-order Laue zone, but with thin crystals or crystals of large lattice parameters the higher-order Laue zones may contribute to the diffraction pattern. Accordingly the program will generate successive Laue zones and project them onto the zero-order zone. The output of the program first lists the zone axis [C, V, W] and the Laue zone, and then gives a list of permitted reflections and the corresponding XP and YP coordinates of the reciprocal lattice point in angstroms-'. In addition, ZP, the perpendicular distance of the reciprocal lattice point from the (U, V, Ur) plane in reciprocal space is given, as is the reciprocal interplanar spacing. In the case of the zero-order Laue zone ZP is zero. A diffraction spot from the higher-order Laue zones will be very slightly displaced from the computed coordinates as its position in an actual pattern is given by projection along the diffracted beam2 and not along [u, V, w]. For any given electron wavelength this correction could be readily incorporated into the program, but as it only amounts to -1 pct it was decided to leave the program in its most general form, i.e ., a computation of points

Jan 1, 1970

By Lyall Zickrick

NUMEROUS brands of virgin pig lead are used in the manufacture of lead and lead-alloy cable sheath for commercial cables. In changing from one brand of pig lead to another a readjustment of press operating conditions is nearly always necessary. This is due largely to different flow characteristics, and some brands extrude at a much lower pressure than others; for example, copper-bearing lead requires much more pressure than a low-bismuth lead under the same operating conditions. With the modern type of lead press the extrusion practice in general differs very little. Molten lead at a temperature of 375° to 400° C. (710° to 750° F.) is cast in a water-cooled cylinder and allowed to cool or solidify into a slug for six to nine minutes. . This slug is forced into the die block and around the core tube through which the cable runs. The die block is held at an optimum temperature by means of gas flames, usually 175° to 225° C. (350° to 4.35° F.). Measurements of the tem¬perature of the cable sheath taken at the time of extrusion have covered a range of 190° to 225° C. (375° to 435° F.). According to Tammann, the rate of extrusion for a metal under constant pressure through a simple orifice is almost doubled for each 10° C. rise in temperature. Because of the irregularity of die-block construction, such a great increase is not obtained in lead-cable extrusion practice. To obtain more" definite information about the effect of small per¬centages of metals usually present as impurities in virgin pig lead, a series of compression tests were made covering several different brands of lead and various alloys. Since the usual temperature of the sheath is approxi¬mately 200.° C. as it emerges from the die block, these compression tests were all performed at 200° C. Five different brands of virgin pig lead were selected, as follows: Brand A: A desilverized western lead of very high purity. This lead contains neither copper nor bismuth. Brand B: A bismuth-free southeastern Missouri lead, usually con¬taining 0.05 to 0.08 per cent copper. Brand C: A copper-free mid-western desilverized lead of very good grade, usually containing around 0.06 to 0.10 per cent bismuth.

Jan 1, 1932

By R. E. Ogilvie, H. C. Gatos, R. E. Hanneman

The effect of high pressure on the stability of the (any phase transformation in the Fe-V system was studied by experimental and theoretical methods. The maximum solubility limit of the y loop of the atmospheric phase diagram was found to increase by a factor of five at 40 kbars pres-sure. The solubility limits of (Y and y phases are calculated on an approximate thermodynamic basis at pressures of 20, 40, and 50 kbars as a function THE high-pressure behavior of the a =^ y transformation in iron and iron-base alloys has been the subject of considerable interest recently. For those binary or higher-order alloy systems possessing a closed y loop, the effect of pressure is to extend the region of solubility of the more dense y phase. Although quite accurate calculations have been made of the a y temperature-pressure diagram of pure iron,' only very approximate thermodynamic calculations or experimental measurements have been made of the pressure dependence of a ^ y equilibria in binary systems exhibiting a y loop.2"4 of temperature and are found in excellent agreement with experimental results. The experimental high-pressure phase diagrams were determined using binary diffusion couples diffused under simultaneous conditions of high pressure and temperature and analyzed with an electron microbeam probe. Approximate calculations of the stabilizing effect of high pressure on the o phase are qualitatively confirmed by experimental results. These previous calculations have primarily dealt with the slopes of the allotropic a (Y= y phase boundary at terminal solubility. The lack of detailed understanding or accurate experimental results of the pressure dependence of the two-phase a ^ y field has been due, in part, to the types of experimental methods previously employed. The primary purposes of the current paper are twofold: 1) to develop and make use of thermodynamic expressions with the aid of supplementary data, to approximately calculate the pressure dependence of the entire y loop and the two-phase ((Y + y) width in the Fe-V system; and 2) to accurately determine the corresponding experimental high-pressure phase diagrams. The current paper describes the powerful method used which enables the simultaneously measurement of phase equilibria and diffusion under high pressure and temperature. A second paper, part 11, will deal with the effect of high pressure on binary diffusion in the Fe-V system.

Jan 1, 1965

By R. B. G. Yeo

The effects of alloy additions on the M, and A, temperatures of an Fe-22.5 pct Ni alloy have been determined. Increasing amounts of titanium, colum-bium, vanadium, and silicon raise and then lower M,while raising A, cmtinuously. Cobalt raises both M, and A,. Aluminum has little effect on Ms but raises A,. Chromium md nickel lower M, and A,. It is proposed that elements raise M, in accordance with their effect on the Ae3 temperature of iron until the lattice becomes stiffened against the shear transformation so that M, is then lowered. An anomaly, first pointed out by Zener,1 arises in steels when the addition of elements, such as molybdenum and tungsten, which raise the Ae3 temperature, also lower the M, temperature.2'3 During the development of a series of martensitic precipitation-hardening (maraging) steels, the effect of several elements on the transformation of austenite to martensite was studied. The results show that under suitable conditions several elements which raise Ae3 also raise the M, and A, temperatures. PREPARATION OF MATERIALS STUDIED A series of alloys was made in which cobalt, titanium, columbium, vanadium, silicon, aluminum, molybdenum, chromium, and nickel were added to an iron base containing 22.5 pct Ni. The compositions of the alloys prepared are given in Table I. The residual manganese contents of the heats were in the range of 0.030 to 0.35 pct, silicon 0.05 to 0.1 pct, carbon 0.0008 to 0.009 pct, and nitrogen from 0 to 0.004 uct. The allois were made as 50-lb induction heats starting with electro-iron and electro-nickel, melted in air to oxidize impurities. Additions of silico-manganese and ferro-silicon were made after which the power was turned off to allow the products of deoxidation to rise and be skimmed from the surface of the melt. The furnace chamber was pumped down to a pressure of 5 p and the charge was heated to 2900°F for the addition of other alloying elements. The heats were poured into five 10-lb ingots, making successive alloy additions to each. The ingots were soaked for 2 hr at 2300°F and hot-worked to 3/4-in.-diam bars. This stock was heated to 1500°F for 1

Jan 1, 1963

By C. A. Stetefeldt

The iron-ore deposits worked by this Company occur in lenses 200 to 1000 feet long and 5 to 80 feet wide, and stand at an angle of from 65' to 75, with a vertical height of 250 to 500 feet, other lenses occurring below. A number of the deposits were first worked as open pits, which in some cases were carried to the depth of 150 feet, when, owing to the weakness of the walls, underground mining was adopted. While the ore was being removed from the open pit, shafts mere in several instances sunk into the foot-wall, the intention being to mine the ore with breast-stopes of an approximate height of 20 feet, followed by underhand-stopes of the same height, leaving floors between of the necessary thickness to support the walls, or to effect the removal of the ore by means of what is known as the stall system. As the work progressed, however, it was found that the walls (which are of chlorite) were too weak to permit the working of breast-stopes 20 feet high, there being frequent heavy falls of ground from the hanging and, in some instances, from the foot. The plan of following breast-stopes with underhand-stopes was, therefore, abandoned. By working breast-stopes only, but little more than one-half of the ore could be removed, and that only at an excessive cost, the ore being so hard that power-drills with 3 1/8-inch pistons . and 6-inch stroke, working under 60 pounds of compressed air, are able to drill but 8 feet in ten hours as a yearly average, while from 6 inches to 2 feet is a common result of ten hours' drilling. It was plain that some other system of mining must be adopted, and it was proposed to sink by levels of 75 feet, carrying in the cross-cuts from the shafts and working out the ore each way from the shaft from foot to hanging, and from 15 to 20 feet in height. When this has been done, drift-sets consisting of caps and legs are set up the whole length of the opening and connected with the cross-cut; the necessary openings for ladder-ways and chutes or mills are timbered from

Jan 1, 1893

By L. D. Tracy

On Aug. 5 and 6,1918, and Mar. 26, 1919, the writer made an investigation of the mine-water neutralizing plant at the Calumet mine of the H. C. Frick Coke Co. The object of this plant is to develop a process of treating the water pumped from the mines so that it may be rendered suitable for use at the power plants of the mines and also at the coke ovens; at the same time, eventually producing a byproduct which will have enough commercial value to provide a sufficient revenue to place the plant on a self-sustaining basis. The Calumet mine is situated in Mt. Pleasant Township, Westmoreland County, Pa., on a branch of the southwest branch of the Pittsburgh Division of the Pennsylvania Railroad. It is about 6 mi. (9 km.) southeast of Greensburg, the county seat of Westmoreland County. The coal, which is the Pittsburg or Connellsville seam, lies at a depth of about 200 ft. (60 m.) and is brought to the surface by means of a shaft. The output of the mine averages 200,000 tons of coal annually, all of which is made into coke, either at the ovens, at the mine, or at byproduct ovens. There are 260 coke ovens at the mine. The continued development of the coal fields of Pennsylvania and the increased use of electric power in the operation of the mines has brought the problem of an increased water supply for the plants to the attention of the coal operators. This is especially true in the Connellsville coking region, where large quantities of water are used in quenching the coke at the ovens. Many of the streams receive the drainage from the mines; and as this water is highly acid and contains sulfur in various forms, some method of treatment is necessary to render it suitable for use at the plants of the mines. With this end in view, the H. C. Prick Coke Co., about 4 years ago, installed at its Calumet mine a plant for experimental purposes, in an endeavor to develop a process that would provide a maximum amount of suitable water at a minimum cost. From a purely technical point of view, the result of these experiments has been encouraging. The company is now endeavoring to place the plant on a commercial basis.

Jan 1, 1922

By Hollomon John H., L. D. Jaffe Hollomon

For many steel parts it is desired to obtain the maximum toughness consistent with the strength required by the mechanical design. It is generally recognized that the greatest toughness at any given strength is found in steels having a tempered martensitic structure.' and is virtually independent of the composition of the steel2 (except for carbon). The choice of the composition of a steel for the parts in question should be based, therefore, on hardenability considerations and on manufacturing facility and economy. In a recent paper3 the concept of hardenability was discussed and a somewhat new approach to the problem was suggested. The hardenability was defined in terms of the cooling conditions (speed of cooling) required to avoid the pearlite and the bainite reactions. Since all the alloying elements do not have the same effects on the two reactions, the bainitic and pearl-itic hardenabilities must be considered separately. In order to design a steel for a given part, it is necessary to design a composition that has both sufficient pearlitic and sufficient bainitic hardenability. However, this requirement does not fix the combination of alloying elements to be used; an infinite number of steels would have the required hardenabilities. Other considerations limit the choice. For example, decreasing the carbon content increases the toughness at a given hardness, and for this reason low-carbon steels are often desired. Limitations or requirements of refining, casting, or forming practices often affect the level of some of the alloying elements. Price considerations enter. Frequently, however, it is very desirable to minimize the tendency toward quench-cracking while maintaining the necessary hardenability. This paper is concerned with suggesting a method for choosing compositions that will have the required hardenability together with minimum tendency toward quench-cracking. Quench Cracking Since only the case in which the entire part will transform to martensite in the particular quench employed is being considered, the analysis of the quench-cracking problem is somewhat simplified. Quench-cracking arises from the temperature gradients existing throughout the piece during cooling. Because of these temperature gradients, the contraction arising from the decreasing temperature and the expansion arising from the austenite-martensite reaction do not occur uniformly over the parts, and stresses are set up that tend to cause cracking. The temperature gradients can be reduced by decreasing the severity of quench. This, however, requires that the hardenability be correspondingly increased by increasing the carbon or alloy content. An

Jan 1, 1947

By I. H. Pratt

The results of a study on the preparation of thin-film capacitor structures are discussed. The dietectric source material was quartz which was sputtered and deposited onto aluminum electrodes and counter-electroded to complete the metal-oxide-metal structures. This configuration was utilized to evaluate the dielectric, the device characteristics, and related process parameters. The effect of gas sputtering pressure, magnetic field strength, source-to-substrate distance, and power density on the rate of deposition is shown. Increased film thickness uniformity over a 3 by 3 in. area by optimum substrate positioning is indicated. Dielectric constant, dissipation factor, dielectric breakdown strength, insulation resistance, heat treatment, capacitance, and dissipation over the range 400 Hz to 5 MHz are reported. In the fabrication of silicon-integrated circuits, silicon dioxide has found use as a material suitable as a diffusion mask, for surface passivation of the silicon, and for protection of conductive films used for interconnections. Its use as a dielectric for thin-film capacitors in film hybrid circuits has been limited, to a degree, for lack of a compatible processing technique and because of its relatively low dielectric constant. With the recent advent of practical metal-oxide-semiconductor (MOS) field effect devices, the material is now being used to insulate the gate electrode from the conducting channel in the silicon. In this latter application, more stringent requirements have been imposed on .the oxide. A comprehensive resume of the use of silicon dioxide in integrated silicon device technology has been compiled including oxide film and bulk properties, method of oxide formations, and their applications.' A relatively new process to deposit SiO, and other dieIectrics is by rf sputtering, and the purpose of this paper is to describe the behavior of capacitors fabricated with a dielectric which has been sputtered from a quartz target and to indicate the relative effect of several of the process parameters on the film deposition. Work on rf sputtering of SiO2 and other dielectrics has been reported utilizing a triode type of sputtering system as described herein or a diode self-sustained glow discharge system. 2-8 SPUTTERING The process occurs during an electrical discharge in a gas plasma which provides the ions for acceleration to the target to produce the desired sputtering. The necessary plasma can be generated by a dc glow discharge through application of a high potential between two electrodes at approximately 2 to 10 x 10-2

Jan 1, 1969

By William Metcalf

It is the object of this paper to oppose unnecessary changes, and the introduction of new and confusing terms. From the earliest times of which we have ally record on the subject, iron has been divided into general classes. Whether iron was first known in the form of wrought iron or of steel, is a matter of no importance; but at the time when cast iron first became a prominent article of commerce, wrought iron and steel were old products— steel, at that time, being generally made from wrought iron by the process of cementation. As steel was then properly defined as iron containing more carbon than wrought iron, so cast iron was appropriately defined as iron containing more carbon than steel. Until the year 1776, when Huntsman first began the manufacture of a new kind of iron by melting wrought iron and steel in crucibles, the above definitions were all that could be desired. At first, probably, owing to imperfect appliances, only a highly carburized iron was melted in crucibles, and this led to its being called cast steel. If our ancestors had found a name for this material not involving the use of the word steel, we would have been saved the trouble of the present discussion. As the arts developed, new uses were found for steel, and the products of the crucible were varied, until at the present day it is quite common to find steel containing no more carbon than average wrought iron, and other steel containing nearly or quite as much carbon as some cast iron. All of these various products of the crucible have retained, or received, the name cast steel, usually abbreviated to the simple word steel, without caus-ing any confusion among producers or consumers in regard to terms or their meaning. In 1865, twenty-one years ago, the Bessemer process was introduced ; this was followed in a few years by the Siemens-Martin process, and the products of both were at once, and have ever since been, called steel, from the fact that they were identical in chemical and physical properties with crucible cast steel. At the present time, then, we have three subdivisions of cast steel, viz.: Crucible cast steel, Bessemer cast steel, and Siemens-Martin,

By Louis A. Carapella, William E. Shaw

MAGNESIUM and its alloys have long been characterized as possessing limited capacity for mechanical forming at atmospheric temperatures prior to rupturing despite their outstanding performances in this respect at elevated temperatures. Responsible for this behavior are the fundamental facts that these hexagonal-type metals have comparatively few slip elements at low temperatures for any extensive deformation and that, at high temperatures, additional slip elements become operative, thus enhancing greater plasticity under strain. The transitional point has been set at 225°C by Schmid1 for single crystals, and at 250°°C by Morell and Hanawalt2 for extruded magnesium metal. In a recent X-ray investigation on polycrystalline magnesium-alloy sheets, Barrett and Haller3 have revealed that, below the transitional temperature, the initial plastic deformation proceeds mostly by a twinning action; that, above such a temperature, the action is mostly by slip. The deep-drawing performance of the magnesium + 1.5 pct alloy sheett over a wide range of temperatures has been investigated by Weber and Vanden Berg,' and their results are presented in Fig r. It should be noted from this work that a maximum drawability of about 25 pct at room temperature has been obtained on this alloy under the conventional deep-drawing operations. For the same alloy, it is now possible to augment the cold drawability to about 40 pct by a process to be disclosed. Hitherto, this value has been obtained only by deep-drawing the alloy at around 230°C. That greater plastic flow is attainable at atmospheric temperatures on magnesium under certain deformational techniques was discovered by the authors6 in their analyses of plastic-deformational behaviors of pure magnesium. This fact is best illustrated in Fig 2 from the Hargreaves analysis6 performed by the authors under two different modes of loading. For direct test, a separate unstrained specimen was used for each load duration, whereas for the integrated test the same specimen was employed for all the five intermittent loadings so that the load duration was made additive throughout the investigation. The higher plastic flow-rate at room temperature, as designated by the Hargreaves constant S, was obtained by the integrated or intermittent loading procedure. The authors5 in further tests showed that, under such a procedure greater plastic flow was also realized with a progressive increase in deformational loads. These findings have been applied

Jan 1, 1947

By Thos. W. 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 be 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 fist 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 conveniencea 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 company, 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 depeind 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 1, 1920

By G. A. Croes, N. Schwarz

This paper reports the results of a series of model displacement experiments carried out for measuring the efficiency of the water-drive process. This series forms a continuation and extension of that described by Engel-herts and Klinkenberg. Detailed information has been obtained on the influence of the oil/water viscosity ratio. The results are represented in the form of a diagram from which both the oil recovery and the water/oil ratio can be easily read off as a function of the total production (oil plus water) for all values of the viscosity ratio M between I and 500. These resu1ts are viewed in the light of the two existing theories on water flooding, viz. that of Buckley and Leverett and that of Dietz. It is shown that if the Buckley-Leverett theory applies, the relation between the relative permeability ratio and saturation, which plays a major role in this theory, (.an be calculated with a high degree of accuracy from the results of the model experiments. Dietz's theory is found to be in agreement with the experimental results in a certain range of circumstances. A discussion of the physical background of the Buckley- Leverett and Dietz theories makes it clear why the latter fails to agree with some of the experimental results. INTRODUCTION For an economical exploitation of oil fields both a rational control of natural (primary) recovery processes and a proper application of artificial (secondary) recovery methods are essential. These require detailed information upon the dependence of the relevant flow processes on the variables by which they are governed. Three methods are available for obtaining this information: (1) (statistical) analysis of actual field data; (2) appropriately scaled model experiments; and (3) mathematical analysis of the physical problem. If sufficient data were available, the first method would, in principle, be the most reliable one, although it has the drawback that the basic relationships between the variables involved are to a large extent obscured by the natural inhomogeneities of most reservoirs. The most profitable procedure seems to be: (a) determining the fundamental relations for idealized reservoirs by methods (2) and (3); (b) checking the consistency of the results obtained by these two methods; and (c) establishing the range of applicability of these methods to actual reservoirs by comparison with the data accumulated under (1). In this paper items (a) and (b) are dealt with for the case of homogeneous loose sands initially saturated

Jan 1, 1956

By T. A. Richard

We rejoice that the world-war is ended. We are proud of the part played by the English-speaking peoples—all doing equal honor to the traditions they share in common. One of the compensations for the calamity of the past four years is the fact that the Briton and the American, striving together in the cause of human liberty, have learned to understand and to respect each other. The mother country entered the fight resolutely at the beginning, while yet unready to meet the carefully prepared onslaught of the enemy; then the sons from the overseas dominions rallied to the old battle-cry eagerly and effectively; and last, but not least, the stepsons came from across the Atlantic, speaking the same speech, playing the same game, and fighting in the same clean way. It was a great foregathering of those that use the language of Shakespeare and idealize the principles of liberty for which the friends and associates of Shakespeare stood sponsor three centuries ago.' At a time like this it is pleasant to dwell upon the fact that the liberal Englishmen who organized the Virginia company were the pioneers of self-government on the American continent. The Virginia Assembly, convoked in 1619, was the first example of a domestic parliament to regulate internal affairs on this side of the Atlantic.2 The Governor of Virginia, Sir Edwin Sandys, had been a pupil of Richard Hooker at Oxford and from that political teacher he and his friends had imbibed the idea of combining civil liberty with constitutional order. To this group of large-minded Englishmen, the American colonists owed their liberal charters and their successive triumphs over the royal prerogative. Let it be noted that the American colonists had to deal with James II and George 111, the two smallest minds in the list of British kings. Another historical note, more pleasant to record, is the connection between the two principal groups of American settlers. In 1608, when the Pilgrim fathers, William Brewster and John Robinson, led their Separatist congregation to Holland and there prepared the expedition to America, they were assisted by Sandys and the Virginia Council, who were willing to share their privileges with them. When the Pilgrims set sail in 1620 they had the promise, obtained by Sandys from King James, that they should have freedom of worship,

Jan 1, 1920

By Harold B. Janzen, M. A. Nobles

Campbell and Martin1 described a new exploratory logging tool which was developed as the result of a new concept of the phenomenon that takes place when a porous formation containing mobile hydrocarbons and irreducible interstitial water is invaded by mud filtrate. They postulate that invasion will create a bank of interstitial water between the flushed zone and the undisturbed formation. This postulate was confirmed by Wyllie.' Thus, if R,, is greater than R, and mobile hydrocarbons are present, the resistivity profile with increasing radii from the borehole is high:low:high, as shown in Fig. 1. If mobile hydrocarbons are absent, the bank of interstitial water is indistinguishable from the undisturbed formation and the resistivity profile, when R is greater than R,, is high:low, as shown in Fig. 2. The zone containing the bank of interstitial water and residual oil was named the "low zone". Campbell and Martin conducted extensive electrolytic wedge and resistivity analog model studies to select a logging system that would reflect the presence or absence of the low zone. The system they selected was that of a family of lateral curves. The model studies indicated that the presence of a low zone could be detected in approximately 60 to 70 per cent of the producing sand reservoirs with a family of lateral curves provided that the sonde effectively occupies 90 per cent of the diameter of the hole. These studies were conducted with D, = 5d. The presence or absence of the low zone is best determined by a plot of the apparent resistivity vs spacing as shown in Figs. 3 and 4. A dip or inflection in the profile that repeats at successive depth intervals is considered diagnostic. To reduce the shunting effect of the hole and mud, a sonde of insulating material that is surrounded by a series of flexible rubber bumpers was designed. The bumper efficiency is considered to be the ratio of the bumper diameter to the hole diameter. Field tests conducted by Campbell and Martin on 10 wells with a tool that provided for station readings indicated that dips or inflections could be detected in 19 out of 25 known producing zones. INSTRUMENT DEVELOPMENT Halliburton developed a logging system to simultaneously and continuously record eight lateral curves. The instrumentation is described in the literature.' The original logs made

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 Marion Rice

The copper-mining district of Jerome, Ariz., is of such economic importance that the following brief notes may be of interest. The ore deposits are said by Ransome1 to be pre-Cambrian, and are contained in the pre-Cambrian schists of the region. In the vicinity of the mine (the United Verde) the schist stands nearly vertical and strikes a little west of north. At least three varieties are distinguishable—(1) a green rock, schistose on its margins but grading into massive material, which is evidently an altered dioritic intrusive; (2) a rough gray schist with abundant pheno-crysts of quartz, apparently an altered rhyolite; and (3) a satiny, greenish gray, very fissile sericitic schist that may be a metamorphosed sediment. The ore occurs in varieties (2) and (3), the main belt of dioritic rock (1) lying just west of the orebodies. The ore is said to follow as a rule the layers of fine sericitic schist. T. A. Rickard2 Says that the ore at the United Verde Extension mine is found at the contact of diorite and schist, that both diorite and ore are earlier than the regional metamorphism, and that the quartz porphyry ("rhyolite" of Ransome) is of post-Cambrian age. The material considered here, a part of which was gathered by the writer, came from four of the mines of the district, and its study was undertaken at the suggestion of Dr. Berkey of Columbia University. The field relations and exact locations of the different specimens are not known, but a microscopic study of the thin sections gave some evidence as to the origin of the ore, which will be discussed below. The indications are that both ore and porphyry were introduced at the closing stages of the metamorphism, this being in accord with Ransome's view of the genetic relation of porphyry and ore rather than with the opinion that the ore is related to the diorite. Certain field occurrences mentioned in the literature also support this theory. Rickard, in the same article to which reference has been made, speaks of a vein of chalcocite several inches wide at the contact of one of the porphyry dikes, and Provot,3 although he regards the porphyry as subsequent to the ore, says: "Acid dikes encountered underground should be followed as they have been found in practice to lead to orebodies."

Jan 1, 1920