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By AIME AIME

AT A meeting of the Iron and Steel Institute held in London on May 6, Dr. J. E. Stead was formally inducted into the chair by Dr. Eugene Schneider, the retiring president. After presenting the Bessemer gold medal to Harry Brearley, of Sheffield, England, for his distinguished services to the British steel industry, Doctor Stead delivered his presidential address, a masterly review of iron and steel making progress during the past 50 years, emphasizing economy in production, and pointing out suggestions for future improvement. A considerable portion of the address was devoted to blast-furnace operation.

Jan 1, 1920

Albert Arents, Alameda, Cal.: From Mr. Furman's description of his crucible-assays I infer that he regards iron nails as a necessary or advisable adjunct. Against such a notion I must beg leave to protest. Nails should not be used in

Jan 1, 1896

MRS. SIDNEY J. JENNINGS, President, MRS. ARTHUR S.. DWIGHT, First Vice-President, MRS. KARL EILERS, Second Vice-President, MRS. H. W. HARDINGE, Third Vice-President, MRS. BRADLEY STOUGHTON, Recording Secretary, MRS. AXEL 0. IHLSENG, Corresponding Secretary, MRS. ARTHUR S. DWIGHT, Acting Treasurer. Welfare Committee MRS. C. C. BURGER, Chairman, Sub-Committees Americanization Belgian Relief MRS. LEVI HOLBROOK, Chairman, MRS. HENRY H: KNOX, Chairman, Emergency MRS. HERMAN A. PROSSER, Chairman. Since the annual meeting held in February, 1917, when the Woman's Auxiliary to the A. I. M. E., was formed, the work of organization, which of necessity must be slow, has steadily gone forward. Under the Chairmanship of Mrs. C. C. Burger of the Welfare Committee, three active sub-committees have been formed: that of Americanization; under Mrs. Levi Holbrook, who is eminently fitted for such a position, by her active and valuable work in a number of the fine patriotic societies of our country; the Belgian Relief Committee, under Mrs. Henry H. Knox, which has clone phenomenal work in the three months of its existence, and whose report is later given in detail; and the Emergency Committee under Mrs. Herman A. Prosser, which has a fund already established, and is. in close touch with Major Arthur S. Dwight, ready to act when necessity arises. The officers of the Auxiliary feel more than gratified at the response so far received, and in a later issue will print extracts from letters, if permission can be gotten from the writers, showing the interest and enthusiasm that have beer aroused by the formation of a Woman's Auxiliary. Answers have even come from far Korea "the hermit nation," from Australia, from South America, showing what a bond of sympathy and, helpfulness is in process of growth. It is our sad duty to announce the death of our Treasurer, Mrs. George D. Baryon, who, from the very inception of our plan to organize, was an inspiring and valuable co-worker. Her place will be difficult to fill. Mrs. Arthur S. Dwight is Acting Treasurer at present. The Auxiliary wishes to express its heartiest thanks to Mr. Stoughton, the genial and efficient Secretary of the A. I. M. E., for his cooperation and valuable suggestions in the difficult work of organizing. He has indeed been "a guide, philosopher and friend." SUSANNE M. IHLSENG (MRS. AXEL 0.), Corresponding Secretary.

Jan 7, 1917

By Arthur Hockman, Howard W. Jaffe, Howard F. Carl

THE problem of establishing practical techniques for evaluating natural corundum ores arose from the desire to improve the existing purchase specifications for crystal corundum procured by the Federal Government for stockpiling. Such purchase specifications had been developed for a large number of products, including minerals and ores considered to be critical and strategic because of the country's dependence on foreign sources of supply. It will be apparent to anyone considering the subject of purchase specifications that the determination of whether or not a submittal meets the specifications is a prime consideration. Consequently satisfactory specifications for minerals should not only incorporate physical, chemical, and mineralogical requirements that are practical but should also establish the means by which both buyer and seller can be assured that materials meet stated requirements. The Munition Board's Material Purchase Specification for corundum, dated February 1954, covered two grades of crystal corundum intended primarily for abrasive use. It established limits of size and of composition: Grade A, at least 95 pct +3 mesh and 92 pct alumina (Al2O3); Grade B, at least 95 pct +7 mesh and 90 pct alumina. It also specified that "of each lot of material, not less than 95 percent shall have a hardness equal to or exceeding nine (9) on Moh's Scale." These specifications were unsatisfactory for several reasons. They did not allow the purchase of lower grades of corundum being used by industry. Neither did they specify exactly what a corundum ore actually was, except that it should contain so much alumina and have a certain scratch hardness. Nothing was said about the abrasive qualities of the material that was to be purchased primarily for abrasive use. During the period 1946 to 1948 supplies of the two grades defined in the then current specifications continued to decrease. Early in 1949 industry recommended that the finer sizes of corundum known as "crystal corundum concentrates," ¼-in. to 16-mesh material, be added to the stockpile specifications and that lower grades of crystal corundum also be included. In the spring of 1949 the National Bureau of Standards and the Bureau of Mines were asked by the Munitions Board to cooperate in developing more practical specifications for grading natural corundum ores. The National Bureau of Standards indicated that it would investigate physical test methods for determining abrasive characteristics of corundum, and the Eastern Experiment Station of the Bureau of Mines at College Park, Md., stated that it would consider the mineralogical aspects of the problem. Members of these two agencies, in consultation with representatives of the Office of Materials Resources of the Munitions Board and of the Federal Supply Service of the General Services Administration, and with the cooperation of industrial suppliers and consumers of abrasive corundum, developed, in a fairly short time, more practical specifications for six grades of corundum ores. The new specifications, issued January 1951, were for corundum, natural crystals, as by this time high-purity synthetic corundum was available and widely used. Nevertheless, for certain specific applications the natural product was preferred over the synthetic material. It has been extensively used in forming snagging wheels. It breaks into more or less cubical particles, whereas artificial corundum fractures into splintery shapes. These produce irregular cuts in glass, while the more symmetrical shape produces a more uniform ground surface. For this reason natural corundum has been preferred for certain types of lens grinding. Pure corundum is clear, colorless alpha alumina (A12O3), but it is rarely found in nature in this form. The most important gem varieties include the blue and yellow sapphires and the ruby. Minute impurities of titanic oxide impart a blue color,

Jan 1, 1955

H. W. MussEn, Collingwood, Ontario, Can. (communication to the Secretary*):—Doubtless all engineers who have paid more than a casual visit to Russia have come into contact with that formidable document, the " smieta," or estimate of the Russian manager. It is an institution which seems to be inseparable from Russian mining-methods. As Mr. Shockley points out, the year's costs a agree very closely" with the figures of the smieta made at the beginning of the year. In cases which have come under my notice, I have been satisfied that there had been a good deal of " rigging" of accounts to this end. The sum spent by the manager was carefully kept down to the total of the estimate, because it was well known that no more money would be forthcoming, and when this is done it is not a difficult matter to see that the right amounts come under the right heads in the final accounts. I do not say that this is always the case, but I have come across notable instances. Looking at it from the Russian owner's point of view, I think that the balance of the argument is usually in favor of the smieta as limiting " impulsive indiscretion" on the part of managers. The Russian Mining Code of to-day leaves much to be desired, but this is thoroughly appreciated by the official world there, and great changes are spoken of for the future. In many, if not in most, cases the laws are interpreted liberally, and a great deal is left to the discretion of the district mining engineer or inspector, with whom it is necessary to keep in close touch. As Mr. Shockley points out, the officials of a mine, who are always Russians, are held personally responsible for accidents resulting to employees, quite independently of any compensation which may be made to the sufferer. This seems startling enough, but I have always found that a penalty is imposed only

Jan 1, 1909

By G. H. Fancher

Improving economic conditions are reflected in the statistical picture of the petroleum and natural gas industry for 1933. Prices were better, demand was greater and the volume of production increased. The increase in the production of gas has been due mainly to the utilization of outlets to the new prolific gas fields of Potter and Tioga counties; of oil, to the growing demand for Pennsylvania grade lubricants. It should be emphasized that nowhere is volume of production more subject to control due to the extensive use of secondary methods of recovery and regional peculiarities than in Pennsylvania. A summary of developments in production for Pennsylvania in 1933 of necessity is brief. The data listed in Table 1 are all too few in number and not all that is desirable from the standpoint of accuracy. No state agency for the collection of data exists, no reports are compulsory. Nevertheless, because of the hearty cooperation of many individuals and public spirited corporations, it is believed that the data are as reliable as are obtainable at the present time. Furthermore, records of the past too often are lost, were never in existence or are fragmentary, to say the least. Illustrative of the condition is the fact that no thorough study of the oil and gas-producing regions has ever been made. The publications of the Pennsylvania Topographic and Geologic Survey upon the subject are noteworthy and valuable, especially the most recent one.' The Survey has been handicapped in the work by lack of time, personnel and funds in addition to the difficulties mentioned previously. It is obvious, therefore, that Table 1 cannot be completed for Pennsylvania. The data simply are not in existence. Officially there are 328 oil and gas pools or fields known by name and 58 distinct sands or horizons, one or more of which are productive of oil and gas in the various pools, but reliable data for only three general regions could be assembled.

Jan 1, 1934

By R. Maddi, I. R. Kramer

The delay time for the initiation of slip was studied in single crystals of a brass, aluminum, and ß brass. A delay time for slip was found in ß brass when the specimens were tested below room temperature; however, one was not found for a brass or aluminum. A general theory for the existence of the brittle transition temperature is proposed. A LTHOUGH a considerable amount of effort has A been devoted to the study of the deformation and fracture of single crystals, the vast majority of the work was concerned with static tests or with tests carried out at relatively slow strain rates. The necessity for the study of a possible incubation time for slip becomes apparent when the various theories which have been postulated for the elucidation of the mechanism of slip are considered. The existence of an incubation period would strongly indicate that slip occurs by a process of nucleation and growth; whereas the absence of an incubation would present rather convincing evidence that slip occurs by a cataclysmic process. In addition to shedding light on the process of plastic deformation, an understanding of the early stages of plastic deformation may be helpful in finding an explanation for the brittle behavior of the body-centered metals under certain conditions. It is well known that these metals, such as iron, molybdenum, tungsten, ß brass, etc., will become brittle as the test temperature is lowered or the strain rate is increased. In spite of the fact that this subject has received considerable attention since the turn of the century, no adequate theory exists today which explains the phenomenon. In the ductile temperature range the metal breaks with a "fibrous" fracture after considerable slip has taken place. In the brittle temperature range the metal fails essentially by cleavage on the {loo) planes: however, some plastic flow is always present even in the most brittle fractures. It is possible, as will be explained later, to ascribe this brittle behavior to the length of the incubation time for slip. Clark and Wood,' using polycrystalline metals, showed that a delay time existed for the yield point in mild steels and that the delay time depended upon the applied stress. These authors stated that the delay time was observed only with those materials for which the stress-strain curve showed a definite yield point. In their work only the mild steel specimens exhibited a delay time at the yield point, while the other materials studied-type 302 stainless steel, SAE 4130 normalized steel, SAE 4130 quenched and tempered steel, 24s-T aluminum—did not show a delay time. These authors' in an extension of their work, found that as the temperature was lowered the delay time was increased. It is, then, the purpose of this investigation to measure or to set an upper limit on the delay time for plastic flow in single crystals of a brass, aluminum, and ß brass. The delay time will also be studied as a function of temperature. The incubation time may be measured by determining the length of time the specimen will support a stress without slip occurring when the stress is greater than the static critical resolved shear stress. In order to accomplish these measurements use was made of a pendulum which was so designed that a single crystal specimen could be placed at various positions along its length. When a pendulum is struck by another pendulum of the same length, an elastic wave is transmitted down the bar with the velocity of sound in the material and is reflected from the far end of the bar. The reflected wave then travels back and unloads the stress until it reaches the impacted end of the bar and the two pendulums separate. The length of time that the specimen is subjected to the stress is equal to the time it takes for the stress wave to travel twice the distance from the specimen to the end of the bar. The stress applied to the specimen is governed by the velocity of impact of the two pendulums. The stress at which the specimen first suffers plastic: deformation was determined in these experiments by examining the specimen under the microscope for the first appearance of slip lines and by measuring the residual strain after each impact. In these experiments the critical resolved shear stress was approached from the low stress side and no attempt was made to determine it exactly. To determine it exactly, it would have been necessary to find that stress at which slip would have just started. However, since the stresses were increased in rather small increments the critical stress is believed to be approached rather closely, as will be seen from the experimental results. The critical stress will be taken as the highest stress obtained before the onset of plastic deformation. The stresses

Jan 1, 1953

By Mark J. Klein

The behavior of nitrogen in Cr-0.12 at. pct Y was studied in specimens of varying interstitial concentration and thermal history. It was found that soluble nitrogen can be introduced into this alloy by increasing the concentrations of either oxygen or nitrogen. For low nitrogen concentrations the nitrogen in solution is low relative to that in unalloyed chromium. However, the nitrogen in solution increases with increasing nitrogen concentration, approaching that in unalloyed chromium. When the alloy is supersaturated with nitrogen, the nitrogen precipitates readily from solution as a chromium nitride. The stress -induced relaxation of nitrogen is influenced by internal oxidation or internal nitrification of this alloy. THE addition of small concentrations of reactive elements such as yttrium have been found to enhance the low-temperature ductility of chromium.&apos; However, the mechanism by which the ductility is increased is not known. It has been suggested that this effect is caused by a drastic reduction in the concentration of nitrogen retained in solution and therefore a decrease in the number of dislocations locked by nitrogen, a factor that has been associated with an increase in ductility.1,2 However, a change in the type of interstitial precipitate induced by yttrium could also contribute to enhanced ductility of the alloy, since chromium nitride precipitates appear to be embrittling.&apos; In this regard, it has been shown that yttrium scavenges nitrogen in chromium to form YN,4 thus reducing the embrittling chromium nitride phase. However, the change in nitrogen solubility induced by yttrium and the partition of nitrogen between chromium and yttrium nitrides are not known. The object of this investigation is to study the effect of yttrium on the behavior of nitrogen in chromium to obtain information relevant to the mechanism by which scavengers enhance the ductility of chromium. EXPERIMENTAL PROCEDURES The experimental procedures used in this investigation have been described in detail elsewhere.5,6 Wires of Cr-0.12 at. pct Y, 15 cm in length and 1 mm in diam, were drawn from rods 0.6 cm in diam supplied by the General Electric Co. The grain size of the wires after recrystallization at 1150°C was somewhat nonuniform, varying from 0.006 to 0.06 mm in diam. The interstitial analysis for the wires in ppm by weight was about 160 0, 80 N, 12 C, and <2 H. Heat treatments were carried out after encapsulation of the specimens in quartz tubes containing argon. Changes in interstitial concentrations, or interstitial "loading" as it is termed in this study, were generally accomplished by annealing in oxygen, ammonia or methane at 1150°C. The internal friction was measured using a conventional torsional pendulum enclosed in an evacuated chamber. Electrical-resistivity measurements were made at liquid-nitrogen temperature.

Jan 1, 1967

By J. W. Harshbarger, E. L. Montgomery

The region of metallic ore deposits in northern Chile, southern Peru, western Bolivia, and northwestern Argentina occurs in arid zones at altitudes as high as 6 km (19,700 ft). Because surface water supplies are meager, new mines require unexploited sources of water. Prolific ground water aquifers occur in salar basins in this region of the Andean Highlands. Exploration water wells have been constructed and aquifer characteristics have been tested in eight salar basins. Results indicate ground water quality is good. Aquifer transmissivity and storage computed from results of pumping tests indicate maximum capacities of more than 170 L/sec (2700 gpm) for individual production water wells. Results of investigations conducted by the authors demonstrate that ground water reservoirs in the Andean Highlands comprise a source of large quantities of water for the mineral industry.

Jan 1, 1986

By N. Christensen, B. Augland, T. H. Johansen

Samples of an Fe-Nb alloy were brought to equilibriurtr with hydrogen-methane mixtures in the temperature range from 950° to 1050°C, and subsequently analyzed on their carbon contents. The solubility pvoduct L = [%Nb] [%C] may be represented by the equation Approximate solubilities indirectly assessed through hardness measurements have been included from a previous report. These data are shown to be in a fair agreement with the present solubility measurements. IN an investigation based on hardness measurements by de Kazinczy, Ms, and pachleitnerl the molal heat of solution of NbC was estimated to 11.5 kcal per mole. This value was considered rather small, and an investigation using a similar technique was carried out. The results indicated a heat of solution about 35 kcal per mole.2 At this stage it was decided to determine the solubility under conditions of true equilibrium . During the course of this work a similar investigation was published by Smith. 3 His heat of solution, 41.6 kcal per mole, is not very different from the value resulting from the present work (42.5 kcal per mole). Our solubility product, on the other hand, is at considerable variance with that reported by Smith. Possible reasons for these differences are discussed below. Mori, Tokizane, and saheki 7 have studied the behavior of niobium in commercial steels, with special attention to the formation of niobium carbide, nitride, and sulfide. Assuming a carbide composition Nbco.87 based on X-ray diffraction and chemical analysis of residues extracted from Fe-Nb-C-S alloys, the molal heat of solution of niobium carbide was estimated to 35.2 kcal per mole. MATERIALS AND EQUIPMENT The chemical analysis of the materials is given in Table I. Electrolytic iron* was used in the preparation of

Jan 1, 1968

By D. G. Westlake

THE structure observed in thin foils by transmission electron microscopy is not necessarily representative of the initial bulk material. We have shown that hydrogen, originally present in a specimen of vanadium, niobium, or tantalum, can be concentrated by the thinning operation used to prepare foils from the bulk materials.&apos; These foils exhibited domain walls indicative of a tetragonal distortion of the bcc unit cells, probably caused by ordering of the hydrogen in preferred interstitial sites. We believe this ordering does not occur at room temperature in the bulk material which contains less than 1 at. pct H. In a continued effort to prepare metal foils whose hydrogen concentrations remain constant during preparation, we have developed some new chemical and electrothinning techniques for vanadium. Each of the procedures presented in Table I produced foils that were thin enough for transmission electron microscopy. The experiments described below were performed to test the effect of each thinning procedure on hydro-

Jan 1, 1968

By N. D. Shutler

This paper describes a numerical mathematical model of the steamflood process that depends on fewer restrictive assumptions than models previously reported. The solution, however, is obtained economically. Example calculations are presented that, on comparison with experimental results, tend to validate the model. Results that expose certain process mechanics are discussed. The model describes the simultaneous flow of three phases — oil, water and gas — in one dimension. It includes the effects of three-phase relative permeabilities, capillary pressure, and temperature- and pressure - dependent fluid properties. Interphase mass transfer of water-steam is allowed, but the oil is assumed nonvolatile and the hydrocarbon gas insoluble in the liquid phases. The model allows heat convection in one dimension and two-dimensional heat conduction in a vertical cross-section spanning the oil sand and adjacent strata. The hydrocarbon-steam gas composition is tracked, but the effect of gas composition on water-steam phase behavior is neglected. The model is solved numerically in three separate stages. The three-phase mass balances are solved simultaneously using Newtonian iteration on nonlinearities occurring in the accumulation terms. The energy balance is solved separately by noniterative application of the alternating-direction implicit procedure. Separate solution of the composition balance is accomplished by straightforward solution of the finite difference equations. The method of effecting nonsimultaneous, stable solution of the mass and energy balances is the key to the success of the model. INTRODUCTION Mathematical tools as well as laboratory and field experiments are necessary to help us understand the complex steamflood process. A mathematical model can expose process mechanics and show the relative importance of process variables, but this ability is often limited by restrictive assumptions. Most known models of steam processes,l-5 with the exception of the model of Gottfried,6 are "simplified" in that they involve analytic approximations and require many restrictive assumptions. The primary utility of these methods lies in the routine use as an aid in engineering design. By contrast, the comprehensive model presented here is numerical and requires far fewer restrictive assumptions. It finds its primary utility as a research tool. It serves as an aid in understanding the nature of the process, in interpreting laboratory experiments and in evaluating and developing simpler mathematical models for engineering design. The major reason why previously presented models have been confined to the "simplified" class is evidenced by the one published exception. In 1965, Gottfried6 presented a numerical model for the combustion process of which the steam process is a subset. The result is a comprehensive tool (though it neglects capillarity and two-dimensional heat conduction) that is troubled with convergence problems and that requires 2 to 3 hours of IBM 7094 time to complete a calculation. Though our present model does not simulate combustion, it does consider capillarity and two-dimensional heat conduction and it overcomes the convergence and computer-time problems. MATHEMATICAL DESCRIPTION OF STEAMFLOODING FLUID FLOW The equations employed to describe three-phase fluid flow are of a familiar form. Darcy&apos;s. law provides expressions for the velocities of the three phases (oil, water and gas), which, when combined with oil, water and gas mass balances, give the partial differential equations governing flow of the

Jan 1, 1970

By R. T. Gallagher, C. G. Brennecke

This paper is the result of a research program entered into cooperatively by the General Reinsurance Corporation and Lehigh University in January 1944. The research program was instituted to find a more positive method to determine the presence of hazardous roof conditions in mining operations. The co-authors, together with Mr. R. D. Currie, Engineer for the General Reinsurance Corporation, started working on the project in January 1944, first undertaking a library search; second, a preliminary study based on some existing equipment; third, the design of new and more suitable equipment; and finally, the field testing of equipment and methods. PURPOSE Any study of the accident statistics of mining operations will disclose the rather startling fact that approximately 50 to 60 per cent of all fatal underground accidents in the anthracite and bituminous mines are caused by falls of roof and coal, the metal and nonmetal mines showing only a slightly smaller percentage. Advancements in safety engineering have produced definite results in the decrease of accidents due to blasting, haulage, electricity, and explosions but no such decrease is shown in those caused by falls

Jan 1, 1946

By J. D. Livingston, H. E. Cline

Cu-Pb alloys in the vicinity of the monotectic composition have been directionally solidified under a high temperature gradient at rates up to 2 X l0-&apos; cm per sec. Over a wide range of compositions, high growth rates yield a composite structure consisting of continuous rods of lead in a copper matrix. This range of compositions increases with increasing growth rate, in agreement with arguments based on the relative velocities of composite growth and the growth of copper dendrites or lead drops. The breakdown of the composite structure at slow growth rates is explained in terms of the relative interphase surface energies. The observed interrod spacings of the composite structure are large compared with the predictions of the Jackson-Hunt equations of eutectic growth. ThE directional solidification of many eutectic alloys produces fine composite structures of parallel lamellae or rods. There has been considerable interest not only in the fundamentals of this two-phase solidification process,&apos;-3 but also in the interesting physical properties produced by such regular and aniso-tropic microstructures. Composite structures can be grown only over a limited range of composition, beyond which coarse primary dendrites of one phase appear. In organic eutec-tics, this composition range of composite structures has been shown to increase with increasing growth rate.7"10 These results were explained in terms of the relative velocities of composite (coupled) growth and dendritic growth. Although similar arguments should apply to metallic eutectics,11-13 suitable experimental results are lacking. In contrast to the work on eutectics, the directional solidification of monotectic alloys has received little attention. (The monotectic reaction is similar to the eutectic reaction, except that one of the resulting phases is a liquid, which subsequently solidifies in a separate reaction at a lower temperature.) Directional solidification of some monotectic alloys&apos;4715 yields regular rodlike microstructures, whereas in other cases macroscopic separation of solid and liquid phases occurs.16 chadwick17 rationalized these results in terms of the probable relative magnitudes of the various interphase surface energies. A recent study of chill-cast Cu-Pb alloys18 revealed a fine rodlike microstructure in alloys near the monotectic composition. It was decided to investigate the directional solidification of such alloys, and to determine the range of composition and growth conditions yielding composite structures. The Cu-Pb system is convenient for such a study, both because it is simple metallurgically, with no compound formation and negligible solid solubilities, and because its basic properties are well-documented. Recent literature on the Cu-Pb system includes studies of bulk thermo-dynamic properties,&apos;g surface energies,20"21 densi-ties,25 and diffusion constants.a6 A similar study of the directional solidification of Cu-Pb alloys was recently undertaken, independently, by Kamio and Oya." EXPERIMENTAL Alloys were prepared by melting 99.999 pct Cu and 99.999 pct Pb in a graphite crucible, stirring well, and pouring into a cold graphite mold. Rods 0.175 in. in diam were machined from the ingots. Alloy compositions studied ranged from 25 to 55 wt pct Pb. Samples were placed in graphite crucibles 5 in. long with 4 in. OD and 0.035-in. walls. They were melted under flowing argon in a vertical, two-zone. platinum -wound furnace. A voltage stabilizer was used to minimize fluctuations in input power. The narrow specimen diameter minimized convection. Directional solidification was achieved by driving the crucible downward into a +-in. hole in a water-cooled copper toroid. The toroid was located immediately below the narrow end zone of the furnace. The end zone was separately powered to maintain high local temperature. Therefore a high temperature gradient (approximately 300 deg per cm) was maintained in the specimen throughout the run. The crucible motion was screw-driven. and a wide range of drive speeds were available. The limited rate of heat removal caused a thermal lag in the specimens at high drive rates. However. temperature-time curves from thermocouples imbedded in a representative sample indicated that the average growth rate still approximately equaled the drive rate. Although the specimens were initially homogeneous, melting and re solidification redistributed the lead. producing composition variations of several percent along the specimen length. (During melting. lead melted first and ran down the sample surface. Rapid freezing tended to reproduce the resulting composition gr~dient, but slow freezing did not because a slow-moving interface tended to reject lead. as discussed later.) To determine local composition. ;-g samples were cut from regions exhibiting various microstructures and were chemically analyzed for lead content. Micrographs were taken on as-polished or lightly etched surfaces. Three-dimensional structure of the lead network was viewed with a scanning electron microscope after removal of some of the copper matrix with nitric acid. RESULTS Several different microstructures are observed, depending on composition and drive rate. Because melting and resolidification produced composition gradients, results are best presented in t&ms of final local composition, rather than initial or average composition. The ranges of local compositions and drive

Jan 1, 1970

By W. V. Swarzenski

In its effort to combat waterlogging and soil salinity, the Water and Soils Investigation Division of WAPDA (West Pakistan&apos;s Water and Power Development Authority) has carried out an extensive program of test drilling andwater sampling since 1954. Data collected during the past ten years have permitted the delineation of fresh and saline groundwater zones in the Punjab Plain. Fresh groundwater containing generally less than 500 ppm of total dissolved solids is found in wide belts paralleling the major rivers and in other areas of fresh-water recharge. Locally, fresh groundwater extends to depths of 1500 ft and more. Saline groundwater occurs down gradient from sources of recharge, particularly in the lower central parts of the interfluvial areas, and presumably underlies most of the Punjab Plain. The groundwaters of the Punjab are characterized by their evolution from calcium, magnesium bicarbonate waters near sources of recharge to waters containing a dominant proportion of sodium. The highly mineralized waters of the Punjab are generally of the sodium chloride type, whereas in the Dera Ismail Khan District, sodium sulfate waters predominate. The pattern of distribution of saline groundwater zones and the observed gradual increase in mineral content, down gradient from sources of recharge, can be explained best by a hypothesis stressing the process of evaporation from the water table and solution of minerals within the alluvial aquifer. In 1954, detailed groundwater surveys in the Punjab Plain were initiated by WASID, the Water and Soils Investigation Division of West Pakistan&apos;s Water and Power Development Authority. The investigations, undertaken under a cooperative agreement between the governments of Pakistan and the United States, were aimed at the formulation of reclamation measures to improve waterlogged and saline soils, and to assess the groundwater potential of the Punjab and other areas of West Pakistan. The nature and urgency of WASID&apos;s primary task limited the exploration of the alluvial aquifer generally to its uppermost part. About 1030 test holes drilled in 47,000 sq miles of the Punjab defined the nature of the alluvium to depths of about 600 ft and yielded data on water quality to 400 or 500 ft. A report on the hydrology of the Punjab, based on the results of these investigations was published by WASID in 1963.&apos; The present report incorporates data obtained by WASID since 1962 in a program of deep test drilling in the Punjab and the adjacent areas of Bahawalpur and Dera Ismail Khan District, permitting the definition of fresh and saline groundwater zones to depths of 1500 ft in some areas. Groundwater in the Punjab Plain is contained in alluvial deposits, predominantly sand and silt, which extend almost everywhere to depths of 1000 ft and more. The alluvium has been deposited by the Indus River and its tributaries since late Tertiary time and is contiguous with similar deposits in India. The Indo-Gangetic Plain extends from the foothills of the Himalayas to the ancient rocks of the Peninsular Shield in central India and to the ocean. Gradients are generally very low and range from about 1% ft per mile in the upper part of the plain to less than 1 ft per mile in the south and southwest. The monotony of the alluvial plain is broken by scattered bedrock outcrops in two of the interfluvial areas, Chaj Doab and Rechna Doab. The bedrock hills are projections of the northwest-trending Delhi-Shahpur Ridge that is largely buried by alluvium. The rocks of the buried ridge, presumably of Precambrian age, are essentially impermeable and define the lower limit of the alluvial aquifer in parts of Chaj, Rechna, and Bari doabs. Elsewhere in the Punjab, there are no outcrops of other consolidated rocks and their presence below the alluvium is conjectural. The principal areas of bedrock outcrops, near Kirana and Sangla, are shown diagrammatically in Fig. 1. The movement of groundwater through the alluvial aquifer of the Punjab has been described by Green-man and others.&apos; In most of the area, the pre-irriga-tion water table sloped from the rivers downstream and toward the central axes of the doabs, indicating that the rivers were sources of groundwater recharge. As a result of seepage from irrigation canals, water levels have risen as much as 90 ft. In 1960 they were within 5 to 15 ft of the land surface and above the

Jan 1, 1970

By Edward A. Loria

A SERIES of papers on the study of austenite grain A size in cast steels has been published recently.&apos;" These studies show that in the as-cast state, the austenite grains are quite large, for they form as the steel freezes at a very high temperature, but a simple reheating above the critical range produces a new set of austenite grains which, in many instances, is finer than ASTM grain sire No. 8. Furthermore, there is no apparent relationship between as-cast austenite grain size and subsequent grain size produced by heat treatment. The as-cast austenite grain size can be determined easily in plain carbon and low alloy steels which produce a continuous grain boundary f errite envelope in the as-cast structure. In the case of cast steels whose alloy content produces greater hardenability and suppresses the proeutectoid ferrite transforma-

Jan 1, 1952

JESSE L. JONES,* Pittsburgh, Pa.-I would like to ask Miss Erskine if down-draft has been used in any of the foundries where heavy fumes have to be removed, instead of the overhead draft.? L. -ERSKINE.-The system of overhead draft to remove heavy fumes has been very much more successful. The entire efforts of the New Jersey Department of Labor in regard to stabilizing conditions in the foundry are the result of the physical examination of the foundryman himself on first-hand information as to the prevalence of the minor ailments and the bad timekeeping that naturally accompanies them. These ailments are a factor in not only increasing the labor turnover but in increasing the percentage of bad work as well. The physical exertion of the foundryman himself is of course an important factor. In certain standard shops the amount of energy expended runs from 11 to 13 tons of foot-pounds of energy a day. In certain shops on piece work, I found a record of the energy expended per day to run as high as 22 tons. In one shop, during the war period, the management established a bonus system, and the men increased their output from 60 to 100 molds a day. The result was an increase of some 60 per cent. in output, and an increase of 400 per cent. in defective castings. The question of the physical exertion in the unsanitary foundries, of course, is very much complicated by other factors, for which reason the department has devoted a good deal of attention to estimating what is a reasonable exertion in a sanitary, well ventilated foundry. We have met certain physical difficulties in the brass foundries that the iron foundries did not have. All that information is available through our Bureau of Industrial Information. The question of the physical energy exerted by the molder is found to have a very distinct bearing on the question of contracts, for the possibility of increasing production is balanced by the extra overhead involved. JESSE L. JONES.-I would like to ask if any evidence has been noticed of carbon-monoxid poisoning among the employees of the foundries.

Jan 4, 1919

By AIME

TURMOIL has been rampant in the lead producing industry during 1946. The chronic labor shortage was aggravated by various work stoppages in mines, smelters, and refineries, while shortage of materials was widespread. Price uncertainties helped to confuse the situation in many countries and particularly in the United States until the removal of price control in the latter part of the year. At the end of the first year of peace, lead, which had been comparatively plentiful during the war years, was a scarce and high-priced metal throughout the world. It is the hope of the industry that the law of supply and demand, if allowed to operate without interference, will bring about a satisfactory balance between production and consumption. Under these circumstances it is not surprising that there have been few important developments in the metallurgy of lead, though a number of items of general interest to the industry have been reported. An ore body which may prove to be of considerable importance has been discovered at Mpanda, Tanganyika. The scarcity of lead ore is illustrated by the announced reopening of the La Manche lead mine in Newfoundland, idle for 56 years. A new lead producer came into production when Rhodesia Broken Hill started up its new smelter. Lead concentrate of 75 per cent grade is smelted in Scotch hearths and the lead is refined to market grade by the Harris process without desilverizing. Production is about 1000 tons per month. One Australian lead producer, Mount Isa, has returned to lead production after having operated its lead plant for the production of copper during the war. The East Chicago plant of the International Smelting and Refining Co. has been sold to the Eagle-Picher Co.

Jan 1, 1947

By George A. Guess

THE increasing demand for greater speed and more accuracy, in making daily assays of ores and products from mills treating material containing but very small quantities of lead and copper, has caused the older analytical methods to be supplanted by new ones devised to meet the needs of modern work. For " control " work in copper analyses, I had, previous to the present equipment, introduced in my laboratory the ordinary electrolytic method, using hollow cylindrical electrodes, and with these I began a series of experiments in determining the lead-content of daily mill-samples and controls. The results, proving accurate and satisfactory, I then devised, with Mr. H. E. T. Haultain, a cheaper electrode than the ordinary jacket electrode, which costs from $15 to $20,-the expense of the older form making the installation of many units very costly. The form of cathode finally adopted as the most satisfactory, shown in Fig. 1, is cut from 0.001-in. platinum foil. It is 12.5 cm. long, and is divided into a blade 4 cm. wide and 6.25 cm. long, and a tongue 0.7 cm. wide and 6.25 long, the immersion area being 50 sq. cm. and weight 1.5 grams. The blade is first sand-blasted and then corrugated lengthwise, in order to impart the necessary rigidity. Strips of platinum foil 0.001 in. thick, 12.5 cm. long and 0.5 cm. wide, having a median corrugation, form the anodes. Three electrodes are used in each cell, one anode in the middle and one cathode oil each side of the anode. These electrodes are connected to slotted alumi¬num terminals, in which they are held by contact pressure. The terminals are -in. rods, projecting 2 in. horizontally in front of the wall of the cabinet.; at the back the middle electrode (anode) is connected with one pole of the current, and the two outer ones (cathodes) with the other pole.

Nov 1, 1905

By FRANK COLE

THE territory covered in this discussion includes all the states west of the Mississippi river. Agriculture is expanding each year in this section, but until recent years the application of commercial fertilizers as an aid to crop production was not practised to any great extent. The use of commercial fertilizers has increased somewhat, but is still on a small basis as compared with the tonnages used else- where in the United States. During 1928 these western states used 665,100 tons of all classes of fertilizer as compared &apos;with 7,933,600 tons used in the whole United States; or this western area, compromising near- ly two-thirds the land area, uses about 5 per cent of the total fertilizer. To show how large a tonnage one state may consume, North Carolina for the year 192s used 1,349,360 tons of commercial fertilizer or about twice the amount used by 22 western states.

Jan 1, 1930