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By W. C. Ellis

For the purpose of developing combinations of higher strength and conductivity than are obtainable by heat treatment alone in the age-hardening copper alloys, an investigation has been made of the effects of combinations of heat treatment and strain hardening on the properties in question. The investigation was limited to a study of the alloys containing nickel and silicon; nickel, silicon and cadmium; and cobalt and silicon. The experiments made in the course of the study are described in this paper in three groups: 1. The effect of hard drawing subsequent to heat treatment on the mechanical and electrical properties of the alloys. 2. The effect of low-temperature aging on the properties of heat-treated and hard-drawn alloys. 3. The effect of strain on the rate of aging of quenched nickel-silicon-copper alloys.

Jan 1, 1931

By R. W. M. Lai

INTRODUCTION Manganese nodules were first discovered by the H.M.S. CHALLENGER expedition of 1873-76 and have engaged the interest of oceanographers and natural resources engineers ever since (1-4). Manganese nodules, some of them as large as grapefruit, cover vast stretches of the ocean floor throughout many parts of the world. In some areas the ocean floor is literally paved with nodules. The Pacific Ocean alone is estimated to contain 1.5 trillion tons of nodules which are forming at the rate of about 10 million tons per year (2). An analysis of the principal metal values for Pacific Ocean nodules is shown in Table I (5). [ ] The principal ingredients of the nodules are manganese and iron, but they also contain other important associated metal values such as copper, nickel, cobalt, and molybdenum. These associated metal values,

Jan 1, 1980

By D. C. Jillson

THE data on the critical resolved shear stress for zinc single crystals published by Rosbaud and Schmid1 showed many irregularities, as seen in fig. 1. There have been subsequent investigations,2,3 but no one has repeated this work with a wide range of orientations, with specimens of a higher degree of purity and perfection, and with improved experimental techniques in order to determine whether these variations were entirely experimental or whether they might have been due, at least in part, to some feature of the mode of deformation not known or understood. Mathewson4 and others have long felt that the glide observed in a [100]* direction between two (001)* planes in the zinc lattice might be actually the net effect of many consecutive unit glides or movements in two alternating [210] directions (fig.

Jan 1, 1951

By R. L. Loofbourow

The objectives of this report are (1) to indicate what is known of natural rock temperatures as deep as 5000 ft below the surface, (2) to indicate methods for estimating such temperatures in localities where directly measured temperatures are un- available, and (3) to outline as far as possible, areas in the 48 states within which rock temperatures are likely to be low and high. The usual object of temperature measurements in deep mines and wells is to learn the temperature of air or another circulating medium. This usually differs significantly from the undisturbed rock temperature. The subject is complicated further by the variety of the thermal properties and structures of rock masses, the migration of fluids within them, the diversity of the history of rock masses and of the processes which have been at work on them during that history.

Jan 1, 1966

By William E. Greenawalt

Ever since electrolytic copper refining gave promise of success, about a half century ago, efforts have been made to apply the idea to the extraction of copper from its ores. The methods of attack have, usually, been to leach with a dilute acid and then to deposit electrolytically the copper from the resulting solution with the simultaneous regeneration of the solvent used in the process. Many efforts have been made, and many patents have been taken out, both in the United States and abroad, to give this idea practical application, but only within the past few years have the difficulties been surmounted. Leaching and electrolysis, as applied to copper ores, are among the most promising fields in modern metallurgy. New conditions are arising, which will bring the wet methods into prominence; while high freight rates and increasing cost of fuel will tend to limit smelting to highly favored localities. The possibilities offered by the installation of hydroelectric plants and the greatly enlarged range of power transmission will greatly widen the field of electrolytic methods. Electrolytic methods are ideally adapted to hydroelectric development, for the load is constant throughout the full twenty-four hours, and the cost of both installation and operation of hydroelectric plants is not appreciably greater when operating for twenty-four hours than when operating for eight or ten hours; whereas, in fuel-power generation, as also in smelting, the cost is more or less in proportion to the fuel and power used. Nevertheless, fuel-power generation presents advantages in electrolytic methods, as the power plant may be located in a favorable place while the leaching and electrolytic plants may be located at the mine. The ultimate possibilities of the wet methods have yet to be determined. The possibilities of smelting have been thoroughly worked out; there is no unsolved major problem in copper smelting, and it has practically reached the limit of its possibilities. It seems hardly probable that any future improvement, either of method or apparatus, will greatly

Jan 1, 1924

By G. Stuart Jenkins

CONDITIONS at the properties of the Consolidated Coal Co. had reached a point where improvements were almost impractical. The mines, sunk years ago, had shafts and entries so small as to preclude the use of large mine cars. A radical change was necessary in the type of mining and also in the type of mine to accommodate such haulage units. After due consideration, the company decided to enter the field of trackless mining, utilizing belt conveyors and chain-flight conveyors, the belt conveyors to take the long haul, and the chain-flight conveyors to be used for gathering. It was decided not to sink a shaft, but to drive a slope on an inclination of 17 1/2°, which the company believes to be about the limit on which coal can be carried on a belt without rolling back unduly.

Jan 1, 1939

By George A. Desborough, Forrest G. Poole

Marine black-shale samples of Paleozoic age in the western United States that exceed 10 wt % organic carbon contain as much as 5000 ppm vanadium, 5000 ppm molybdenum, 1300 ppm nickel, 600 pprn cobalt, 16 ppm silver, 11,700 ppm chromium, 18,800 pprn zinc, 280 pprn cadmium, and 350 ppm selenium. Depositional set- tings include: (I) continental-rise and marginal- ocean basins, (2) continental-shelf and foreland basins, and (3) cratonic-platform embayments. Most of these metalliferous organic-rich shales have not been examined for resources because rapid weathering and poor exposures preclude easy sampling of unoxidized rock necessary to determine actual concentration and residence of indigenous metals. Generally, when interval thickness is considered, the marine black shales of Paleozoic age in the western United States are richer in metals than marine upper Paleozoic black shales in the eastern United States.

Jan 1, 1983

E L. DEGOLYER, our new president, though a petroleum geologist by profession, has always s been associated with mining, for soon after his birth at Greensburg, Kan., on Oct. 9, 1886, his parents moved to Joplin, and when he went, in the course of time, to the University of Oklahoma, he intended to follow his course there with another at a mining school. He became a field assistant in the U. S. Geo-logical Survey, however, while still an undergradu-ate, and after field experi- ence in Montana, Wyoming, North Dakota, Colorado and Oklahoma, he went to Mexico as geologist for the Mexican Eagle Oil Co. This was in 1909, and as a result he was unable to complete his work for his degree until 1911. In Mexico, he located the Potrero de Llaño No. 4, one of the world's largest oil wells, and also the dis- covery well in the Naran- jos pool; and the Colorado School of Mines conferred the honorary degree of : Doctor of Science on him in 1925. On his return from Mexico, he engaged in the consulting business, specializing in financial ap- praisement, the Union and Marland companies being among his clients. In 1919, he organized the Amerada Petroleum Co., with the backing of Lord Cowdray. Last year, control of the company was purchased by an American group, headed by Dillon, Read and Co. Mr. DeGolyer is n o w president of the company. He is also vice-president and general manager of the Rycade Corp, the Rycade Oil Corp., and president of the Geophysical Re-search search Corp. The l a t t e r represents the practical appli-cation of his inter-est in the use of the torsion balance in the locating of salt domes, in which he has pioneered, the Nash dome being the first oil field in America actually brought into production by these methods.

Jan 3, 1927

By C. E. Nelson

The purpose of this discussion is to outline briefly the practices commonly followed in this country for the melting and refining of magnesium and its alloys. The processes used for the various forms of primary magnesium, as far as there are differences in the physical shape or behavior, will be discussed. The refining of general fine scrap or secondary magnesium was presented in an earlier paper.1 Inasmuch as the use of fluxes is an essential part of all the melting and refining processes, the principal aim of this paper will be to deal with these in sufficient detail to point out their unique characteristics, in order to make their use more effective. Types oF Melting Practice All melting and refining processes for magnesium and its alloys require the use of fluxes. These fluxes have a magnesium chloride base and other halide salts or oxides are added to give a density or behavior exactly suited to the particular melting practice. The successful handling of magnesium depends upon the proper use of the correct fluxes. There are four general methods of melting, summarized in the following paragraphs and treated in more detail in the section on Melting and Refining. Open-pot Method The open-pot method makes use of No. 230 flux.2 The flux provides protection during melting and a molten pool of flux into which the solid magnesium melts. It is stirred through the molten metal bath and agglomerates oxide or similar foreign bodies; then on quiet standing separates away, leaving the refined metal ball floating in an encircling layer of molten flux. It forms only a thin fluid film over the surface of the molten metal, which may be ' parted for hand-ladling processes and tends to cover the metal again after the ladle is removed. A very light dusting of the pot surface with fresh flux immediately after the ladle is removed is usually desirable. The open-pot method is used generally in the following processes: (I) alloying and secondary smelting in the production of ingot, (2) in sand foundries for premelting and to a smaller extent for the production of small castings requiring hand ladling, (3) in permanent-mold founding for premelting and also direct ladling to castings, (4) for continuous methods of preparing metal in the production of billets or ingots from which wrought products are fabricated, (5) in general scrap recovery. Crucible Process The crucible process makes use of No. 310 flux, which has the property of being thinly fluid at the start, to provide protection and refining qualities, and then drying out or thickening after a time, leaving a protecting crust on the pot surface until the time of casting. At that time it can be readily skimmed off or held back, thus allowing the contents of the crucible to be poured out directly into castings without fear of flux contamination. This flux is not

Jan 1, 1944

By Gerhard Derge

The extension of metallurgical control of steelmaking processes has always made it desirable to have some quick method for determining the oxygen content of molten steel. To meet the practical demands of the steel industry, this method must also be simple enough so that the sampling can be done by the regular furnace crew. This requirement was kept in mind continually in the work to be described. An oxygen value is required for proper control, whether it be of a rimming steel or of a fully killed steel. However, two factors have discouraged the development of such direct methods: i. The reaction C + FeO Fe + CO is rapid enough to make the correct sampling Of the bath a difficult problem. The most generally accepted means of circumventing this difficulty have been the aluminum-killed bomb test of McCutcheon and Rautiol and the aluminum-killed spoon test of Herty.2 The theory of these tests is that all of the oxygen in the iron is converted to Al2O3, which can then be determined by chemical methods. Even when simplified so that the analysis is made by a measurement of turbidity, this method is too slow to be used in routine control. Furthermore, the results obtained have never been entirely satisfactory, and some of the reasons for this will be discussed later in this paper. z. The ordinary chemical methods of analysis for oxygen in steel are not reliable. The only analysis that seems to possess sufficient dependability to be of value is vacuum fusion,3 and the apparatus and technique developed for this have been too complex and slow for routine work. Indirect Methods Indirect methods of estimating the oxygen have been resorted to in mill practice. Generally these depend upon the chemical equilibria involved. The oxygen in the bath is related to other components in the slag or metal that can be analyzed the readily. These methods have many difficulties in common. Steelmaking processes involve a complicated set of interrelated reactions, all of which tend to approach equilibrium at varying rates. The degree to which any particular equilibrium is approached is not well established. Moreover, a proper use of theoretical equilibrium constants requires a more extensive knowledge of the activities of the con- than we now have. This is well illustrated by the irregularities observed when trying to determine the oxygen in the metal by its ratio to the iron oxide in the slag. Equiliblium relations may be used mole readily if they are evaluated by plant experience, but the extent of approach to equilibrium remains an undetermined variable and lack of an entirely satisfactory mean, of determining oxygen for the calibration is felt keenly, For example, the statistical analysis of the relation between carbon and oxygen4.6 illustrates that even iia a single plant wide variations exist under llormal conditions of operation. Never. theless, this is one of the best methods now

Jan 1, 1943

By Gerhard Derge

The extension of metallurgical control of steelmaking processes has always made it desirable to have some quick method for determining the oxygen content of molten steel. To meet the practical demands of the steel industry, this method must also be simple enough so that the sampling can be done by the regular furnace crew. This requirement was kept in mind continually in the work to be described. An oxygen value is required for proper control, whether it be of a rimming steel or of a fully killed steel. However, two factors have discouraged the development of such direct methods: i. The reaction C + FeO Fe + CO is rapid enough to make the correct sampling Of the bath a difficult problem. The most generally accepted means of circumventing this difficulty have been the aluminum-killed bomb test of McCutcheon and Rautiol and the aluminum-killed spoon test of Herty.2 The theory of these tests is that all of the oxygen in the iron is converted to Al2O3, which can then be determined by chemical methods. Even when simplified so that the analysis is made by a measurement of turbidity, this method is too slow to be used in routine control. Furthermore, the results obtained have never been entirely satisfactory, and some of the reasons for this will be discussed later in this paper. z. The ordinary chemical methods of analysis for oxygen in steel are not reliable. The only analysis that seems to possess sufficient dependability to be of value is vacuum fusion,3 and the apparatus and technique developed for this have been too complex and slow for routine work. Indirect Methods Indirect methods of estimating the oxygen have been resorted to in mill practice. Generally these depend upon the chemical equilibria involved. The oxygen in the bath is related to other components in the slag or metal that can be analyzed the readily. These methods have many difficulties in common. Steelmaking processes involve a complicated set of interrelated reactions, all of which tend to approach equilibrium at varying rates. The degree to which any particular equilibrium is approached is not well established. Moreover, a proper use of theoretical equilibrium constants requires a more extensive knowledge of the activities of the con- than we now have. This is well illustrated by the irregularities observed when trying to determine the oxygen in the metal by its ratio to the iron oxide in the slag. Equiliblium relations may be used mole readily if they are evaluated by plant experience, but the extent of approach to equilibrium remains an undetermined variable and lack of an entirely satisfactory mean, of determining oxygen for the calibration is felt keenly, For example, the statistical analysis of the relation between carbon and oxygen4.6 illustrates that even iia a single plant wide variations exist under llormal conditions of operation. Never. theless, this is one of the best methods now

Jan 1, 1943

US 4,137,751-Aerial geophysical exploration for ore deposits by collecting and analyzing atmospheric particulates The aircraft has an Inlet duct extending outward and including a "shave-off" duct, a cyclone separator located inside the cabin which is coupled to the inlet duct, a clean air exhaust duct, and a receiver for the collected particles incoming air is divided into two fractions. The fraction taken by the "shave-off" duct and containing the bulk of the particles is routed to the cyclone Particulates are gathered on a collector tape for subsequent analysis and correlation with the areas covered J. R Rhodes, R D. Sieberg, M. C Taylor, J. C Westkaemper, and R C. Young, assigned to Columbia Scientific Industries, Inc Feb. 6, 1979 7 pp. (73-28) Filed- 2-28-75 (554,114) Same British 1,446,760, dated Aug. 18, 1976. US 4,156,138-Exploration for subsurface deposits of uranium ore Pairs of dosimeters are placed underground in a grid pattern Each dosimeter contains a phosphor which IS capable of storing the energy of alpha particles. One dosimeter is heavily shielded from alpha particles, while the other in the pair is thinly shielded to exclude dust After a period underground the dosimeters are heated to release the stored energy as light. The amount of light produced from the heavily shielded dosimeter is subtracted from the amount of light produced from the thinly shielded dosimeter to give an indication of the location and quantity of uranium underground This patent is a division of US Patent No 4,053,772, dated Oct 11, 1977 P E Felice, assigned to Westinghouse Electric Corp May 22, 1979 5 pp (250-253) Filed. 8-12-77 (824,203) US 4,180,727-Method for measuring the gamma-gamma density of uranium ore in the vicinity of a borehole A first gamma-ray detector receives only natural gamma rays from the borehole, while a second receives both natural gamma rays and scattered uranium-source gamma rays The value of the uranium-source gamma rays is calculated. W W Givens, assigned to Mob11 011 Corp Dec 25, 1979 6 pp (250- 264) Filed 10-20-77 (843,909) US 4,180,72&A neutron activation probe for determining the location and grade of uranium ore, especially where thorium or other fissionable isotopes are present, includes a pulsed neutron source in series with a plurality of delayed neutron reactors for measuring radioactivity in a well bore- hole together with a Nal(T1) counter for measuring the high energy 2 62 MeV gamma line from thorium The signal from the Nal(T1) counter IS subtracted from the signal from the delayed source detectors to ascertain the amount of uranium present in the ore body N. P Goldstein and R C Smith, assigned to Westinghouse Electric Corp Dec 25,1979 6 pp (250-264) Filed. 4-1 1-78 (895,323)

Jan 1, 1980

Receipts General Funds: Initiation fees ' 6,008.50 Arrears of dues 1,772.69 Current dues 46,576.56 Advance dues 1,820.97 Sale of binding 10,554.43 Sale of advertising 6,003.42 Sale of Transactions 3,237.07 Sale of special editions ' 1,722.50 Sale of Bulletins and. pamphlets ' 2,263.95 Miscellaneous Receipts; Interest on investments and deposits 450.06 Sale of pins and fobs 312.80 For the collection of checks 161.84 From Finance Committee, Feb., 1916, Meeting 101.02. Subscriptions to the land fund 86.14 Arizona Meeting refund from N. Y. Central Railroad.. 52.48 Local Section refund from N. Y. Central Railroad.... 31.85 Miscellaneous 425.68 Total Receipts General Funds 81,611.96 Cash balance Dec. 31, 1913 1,063.39 $82,675.35

Jan 2, 1917

By F. B. Eiseman

IT is desired -to determine the effect of the extent of bank repairs on the final slag volume in acid electric steel-melting practice. It is understood that the repairs stud- TABLE I-Summary of Effect of Bank Repairs on Slag Volume [ ] ied here are necessary and the amount of sand added is that needed to maintain hearth and banks in a satisfactory condition. In this way the effect of repair materials on the amount of slag tapped would be found with a reasonable degree of accuracy. Ten heats were made for this study with careful attention to a uniform charge. The steel was the usual grade B and melting was carried out in a 3 1/2-ton top-charge Lectromelt furnace. Melting practice in all cases was the same-complete oxidation, with recarbonization by means of low-silicon pig iron.

Jan 1, 1947

(The following list contains the names of those members of the Institute of whose connection with military service we have only recently become acquainted; it also includes the names of a few who have recently been promoted or transferred, indicated by a *. A complete list was published in the Year Book, issued as a supplement of the Bulletin for March, 1915.) ADAMS, ARTHUR K., Lieut., Co. 2, E. 0. T. S., Camp Humphreys, Va. AMIDON, CLAUDE E., 11th Training Co., Casual Camp, Camp Cody, N. M *BARBOUR, P. E., Capt., Engineer Corps, U. S. A. *BENHAM, W. M., Master Engr., Headquarters Dept., 115th Engrs. A. E. F., Care Postmaster, N. Y. BICKNELL, H. L., Pvt., Co. D, 27th Engrs., Camp Leach, D. C. *BLANDY, S. H. B., Lieut., Royal Horse Artillery, B. E. F.

Jan 10, 1918

By A. W. Bitner, A. W. Asman

An analysis is made of three different types of section production units that represent the manner in which most of the nation's bituminous coal is produced. The general delays and production characteristics of these sections are presented along with a method for evaluating section performance based on actual and theoretical production characteristics. THE forerunner of the modern mechanical loading machine first entered the mines in 1890—a Stanley header with a conveyor. Since then progress has been substantial, both in the design and application of mechanized production units. Mechanization is almost a necessity for survival in the economy of today. In this paper an analysis is made of three types of sections, and a method for evaluating section performance based on present production characteristics and theoretical characteristics is presented. In mechanical loading mining sections the loading machine is the unit directly responsible for production. If the face preparation units provide a plentiful supply of properly prepared coal and the transportation system is coordinated and adequate, the loader will be idle a minimum of time. If either of the above do not perform adequately or other delays occur, the effect on production will be reflected in the performance of the loading machine. Therefore, attention is focused on the loading machine and factors that affect the overall performance of the production unit. Three complete mechanized production units are presented for analysis: A track section, a trackless section using battery-powered shuttle cars, and a trackless section using cable-reel shuttle cars. These particular sections were chosen for the following reasons: 1—The daily tonnage and mining conditions are approximately the same. 2— Production in each is 10 to 20 pct above the daily average. 3—The production characteristics and delays are average and typical. 4—They represent the manner in which the most of the nation's bituminous coal is produced. A. W. ASMAN, and A. W. BITNER, Members AIME, are Chief, and Research Assistant, respectively, Div. of Mining, The Pennsylvania State College, State College, Pa. Discussion on this paper, TP 3140F, may be sent to AIME by Oct. 31, 1951. Manuscript, Feb. 22, 1951. St. Louis Meeting, February 1951. Section A Fig. 1 is a layout for the track mining section showing the development to date, the projected plan and the cuts loaded on the shift studied. The seam mined averages 96 in. in thickness with a fireclay bottom and a roof of 10 in. of drawslate topped by sandstone. The mineability is considered good, and roof support is not a difficult problem. Two locomotives are used in the section to minimize the losses occurred in trip changing. The places are driven 20 ft wide, and the crosscuts are angled to permit fast tramming of the equipment. Table I lists the equipment and labor that make up the section. ANALYSIS Production Characteristics: The average loading rate for eight loading machines studied of this type is 1.81 tons per min. This one at 2.78 is considerably above average.

Jan 1, 1952

By Gerhard Derge

THE extension of metallurgical control of steelmaking processes has always made it desirable to have some quick method for determining the oxygen content of molten steel. To meet the practical demands of the steel industry, this method must also be simple enough so that the sampling can be done by the regular furnace crew. This requirement was kept in mind continually in the work to be described. An oxygen value is required for proper control, whether it be of a rimming steel or of a fully killed steel. However, two factors have discouraged the development of such direct methods: I. The reaction C + FeO -+ Fe + CO is rapid enough to make the correct sampling of the bath a difficult problem. The most generally accepted means of circumventing this difficulty have been the aluminum-killed bomb test of McCutcheon and Rautio1 and the aluminum-killed spoon test of Herty.2 The theory of these tests is that all of the oxygen in the iron is converted to A1203, which can then be determined by chemical methods. Even when simplified so that the analysis is made by a measurement of turbidity, this method is too slow to be used in routine control. Furthermore, the results obtained have never been entirely satisfactory, and some of the reasons for this will be discussed later in this paper. 2. The ordinary chemical methods of analysis for oxygen in steel are not reliable. The only analysis that seems to possess sufficient dependability to be of value is vacuum fusion,3 and the apparatus and technique developed for this have been too complex and slow for routine work. INDIRECT METHODS Indirect methods of estimating the oxygen have been resorted to in mill practice. Generally these depend upon the chemical equilibria involved. The oxygen in the bath is related to other components in the slag or metal that can be analyzed more readily. These methods have many difficulties in common. Steelmaking processes involve a complicated set of interrelated reactions, all of which tend to approach equilibrium at varying rates. The degree to which any particular equilibrium is approached, is not , well established. Moreover, a proper use of theoretical equilibrium constants requires a more extensive knowledge of the activities of the reactants than we now have. This is well illustrated by the irregularities observed when trying to determine the oxygen in the metal by its ratio to the iron oxide in the slag. Equilibrium relations may be used more readily if they are evaluated by plant experience, but the extent of approach to equilibrium remains an undetermined variable and lack of an entirely satisfactory means of determining oxygen for the calibration is felt keenly. For example, the statistical analysis of the relation between carbon and oxygen4 5 illustrates that even in a single plant wide variations exist under normal conditions of operation. Nevertheless, this is one of the best methods now

Jan 1, 1943

By W. C. Ellis, E. S. Greiner

WHEN metallic materials are deformed plastically, the process may be considered as one in which hardening and recovery occur simultaneously. The net hardening is that produced by deformation in the absence of recovery lessened by recovery during and immediately following deformation. Strain hardening takes place through movements of large groups of atoms acting to a degree as an entity. A complex microstress system is developed. Recovery is a diffusive-type process involving single atoms or, at most, only a few atoms in concerted action. This is accompanied by elastic strain relaxation. Recovery is strongly temperature-dependent. The driving energy for the process resides in thermal fluctuations of the atoms augmented by the energy of the stress field producing the deformation, and by that produced by the deformation. At very low temperatures recovery is essentially absent, or very small. At high temperatures in the hot working range, recovery is so rapid that deformation results in no appreciable net hardening. The interplay of strain-hardening and recovery results in differing end structures depending on the temperature and the strain rate of the process. For example, there is a prominent difference in the spacing of the slip markings and in the detail of X-ray diffraction patterns. High temperatures and slow strain rates favor a wide spacing of slip markings and sharp reflections.',' This suggests that change in rate of the recovery concurrent with deformation modifies to a degree the manner of the deformation. Different slip systems may operate. For very slow rates, the mechanism may, as has been suggested, differ from that of "classical slip." In the experimental work that follows the findings will be interpreted from the point of view developed in this section. Recovery and Electrical Conductivity Electrical conductivity is a sensitive indicator of the state of strain in a material3' * and was used in this investigation. The materials studied in wire form were: OFHC copper, a high purity (99.99 pct) and 2s grade aluminum, and grade A nickel. Wire annealed and initially 0.050 in. in diam was drawn through diamond dies in a simple holder maintained at 25", —75°, or — 195°C. Precautions were taken that for each material all conditions of drawing were the same except the temperature. Electrical resistivity was measured for each condition at 20°C. This was done as soon as practical after drawing to minimize possible room temperature recovery. The data for the four materials are plotted in Fig. 1 in terms of the change in resistivity for drawing at the several temperatures. The effect of temperature of drawing on the increase in resistivity is most pronounced for copper. Drawing at 25°C to 80 pct reduction in area increases the resistivity approximately 2 pct; drawing at —195°C to the same reduction increases the resistivity about 6 pct. The increase in resistivity" & in this metal is due to extra scattering of conduction electrons originating in the lack of orderly arrangement of the atoms induced by the deformation process. It has been suggested

Jan 1, 1953

By David White

The submission of carefully prepared estimates of the oil reserves of the United States calls for no apology or explanation. In this country, petroleum is a rapidly wasting asset and an occasional appraisal of the amount remaining in the ground is a simple business procedure to safeguard the general welfare and the prosperity of the republic. The rumored danger of failure, in the near future, of the foreign supply on which we depend in constantly increasing amounts makes the immcdiatc review of our available reserves the more imperative. The Director of the U. S. Geological Survey, in March, 1921, requested the American Association of Petroleum Geologists to cooperate in the preparation of new estimates of the oil remaining in the graund. With the members of this cooperative committee, state geologists, regional geologists, oonsulting specialists, and geologists and engineers attached to many companies worked both independently and through subcommittees. The reports for districts, counties, fields, etc., after review by local or state committees, were discussed by the joint cooperative committee in conferences that, in some instances, were attended by the original compilers of estimates for the states or smaller areas. Finally the data were reviewed and the figures revised by the joint cooperative committee, so that the totals given in Table 1 represent the opinion of the committee, which was composed of F. W. DeWolf, W. E. Wrather, Roswell H. Johnsont Wallace A. Pratt, Alexander W. McCoy, Carl H. Beal, C. T. Lupton, G. C. Matson, K. C. Heald, W. T. Thom, Jr., A. E. Fath, Kirtley F. Mather, R. C. Moore, and David White, chairman. Oil geologists and engineers understand well the speculative nature and the chances of error that must attend estimates of the petroleum in the ground when they cover not merely prospective territory, but possible territory. Neither the character nor the magnitude of the factors of uncertainty is to be disguised. Further, the inevitable differences of opinion between geologists of equal rank and experience must also bc

Jan 1, 1923

By David White

The submission of carefully prepared estimates of the oil reserves of the United States calls for no apology or explanation. In this country, petroleum is a rapidly wasting asset and an occasional appraisal of the amount remaining in the ground is a simple business procedure to safeguard the general welfare and the prosperity of the republic. The rumored danger of failure, in the near future, of the foreign supply on which we depend in constantly increasing amounts makes the immcdiatc review of our available reserves the more imperative. The Director of the U. S. Geological Survey, in March, 1921, requested the American Association of Petroleum Geologists to cooperate in the preparation of new estimates of the oil remaining in the graund. With the members of this cooperative committee, state geologists, regional geologists, oonsulting specialists, and geologists and engineers attached to many companies worked both independently and through subcommittees. The reports for districts, counties, fields, etc., after review by local or state committees, were discussed by the joint cooperative committee in conferences that, in some instances, were attended by the original compilers of estimates for the states or smaller areas. Finally the data were reviewed and the figures revised by the joint cooperative committee, so that the totals given in Table 1 represent the opinion of the committee, which was composed of F. W. DeWolf, W. E. Wrather, Roswell H. Johnsont Wallace A. Pratt, Alexander W. McCoy, Carl H. Beal, C. T. Lupton, G. C. Matson, K. C. Heald, W. T. Thom, Jr., A. E. Fath, Kirtley F. Mather, R. C. Moore, and David White, chairman. Oil geologists and engineers understand well the speculative nature and the chances of error that must attend estimates of the petroleum in the ground when they cover not merely prospective territory, but possible territory. Neither the character nor the magnitude of the factors of uncertainty is to be disguised. Further, the inevitable differences of opinion between geologists of equal rank and experience must also bc

Jan 1, 1923