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By Louis V. Bender

THIS paper gives a short review of the installation for and the use of gas, as a. fuel, at the Anaconda Reduction Works of the Anaconda Copper Mining Co. Before putting in gas tile fuels used were pulverized coal, lump coal, coke distillate and oil. These fuels are now almost entirely eliminated. For nearly fifty years bituminous coals from Wyoming and Montana fields had been used. These coals were of a good grade, analyzing 11,300 B.t.u. and having an ash content of 12 per cent. When hydro-electric power replaced steam-driven equipment, the coal requirements were reduced; and, on account of improvements in metallurgy and/ or in furnace design, the quantity was lessened. Later, oil and distillate were introduced and used in some of the operations. All of these things tended toward the lessening of the amount of coal used, and had it not been for the increase in the size of the plant, the tonnage used would have been small when the change was made to gas.

Jan 1, 1932

By A. Ross Rornmel

ABILITY to speak effectively is one of man's most longed for and coveted abilities. It is the ability to stand on one's feet, transfer knowledge and thoughts to others, to reach an objective professionally or otherwise by leading groups through a channel of planned thought. Each day group speaking plays an important part in making or marring success, and the engineering profession often provides this opportunity and requirement. An ability to speak effectively develops courage, poise, confidence, and prestige for the speaker. The technical man cannot be reluctant to face an audience. He is often called upon to do this in presence of employees, supervisors, and other groups. His ability to speak effectively is as much a requirement as the fundamentals of his profession. The three fundamentals of effective speaking are: (1) Enthusiasm and Confidence. These are joined because of their close relation. (2) Preparation. This includes knowledge of the subject. (3) Presentation. By this is meant the features of delivery.

Jan 1, 1946

By H. B. FERNALD

THE interesting and carefully developed formula which Professor Bucky presents for answering the question of whether proposed new equipment will give a net return on investment equal to or greater than that on present equipment starts with an assumption that the management may make this relative return a determining factor in its decision whether or not the new equipment should be provided. I do not question that in some cases the management may take this position, but I would point out the error involved in so doing. The proper test is not a comparison of the return on new as compared with the return on old investment, but is rather a comparison of the return on a particular new investment as compared with the return which would be obtainable from some other new investment which now might be made. Then I would point out that I believe Professor Bucky is in error in using as a factor in his computations the item of unamortized cost of old investment. The financial advantage to be derived from a new investment does not depend on the extent to which we may in the past have written off the cost of old equipment, nor does it even depend upon what was the original cost of that old equipment. Even the salvage or resale value of the old equipment will only enter into the picture to the extent that the present salvage or resale value differs from the ultimate salvage or resale value otherwise to be obtained, after due allowance for the interest factor.

Jan 1, 1930

By D. J. Weintritt, R. G. Hughes

Statistics show arz increase in the average depth of wells drilled in recent years. As a corollary to this trend, drilling fluids have been improved in an effort to meet the problems inherent at temperatures approaching 500°F. Of importance are (1) deterioration of mud components and (2) the effect of solids on filtration and rheological properties. High-temperature, stable water-base and oil-bare muds are discussed. Those areas in which differences exist are pointed out. Results are based on data taken from the Fann consistotneter, rheometer and shear-strength measurements, static and dynamic filtration tests, methy-lene blue test for bentonite solids and specific heat measLrrenlents of muds. INTRODUCTION Higher well temperatures go along with the fact that the average depth of wells continues to increase. Recent data by Gardner' lists 137 completions deeper than 15,000 ft for the first half of 1964 with a record second-half total of 167 wells drilling or proposed. In addition, there has been an increase in drilling for steam for power production or mineral recovery. In this application the depths are modest, but the mud may approach the critical pressure and temperature of water. Scearce and Magnon' report drilling mud used at temperatures of about 700°F in the Salton Sea area of California. Most deep wells have been drilled with water-base muds. In recent years, however, there has been a substantial increase in the use of oil-base muds because of technological advances in effective additives. The significance of this development was dealt with in considerable detail by Simpson and his co-workers.3 Additiona1 field data have now been obtained to indicate that oil muds are competitive in control, performance and cost with the best types of water muds for use at high temperaturc. This parallel offer of two very different fluid systems, each offering a similar variability in performance, cost and convenience, has created the need to evaluate the merits of these fluids under specified conditions so that the advantages and disadvantages of each can be weighed in relation to the over-all drilling program. This paper is not intended as a review of all the factors. Rather, it attempts to emphasize: (1) important condltions and facts peculiar to high-temperature drilling muds, (2) that more than one imposed test condition or testing method is necessary to describe the quality of a mud at high temperature and (3) that elaborate experimental precautions are necessary whenever laboratory data are used in selection of a mud for field use. WHAT IS A HIGH-TEMPERATURE DRILLING FLUID? For the purpose of this discussion, a high-temperature drilling fluid is any system so formulated or treated to economically minimize the effects of temperature on the properties of the fluid. Our experience in drilling fluids suggests that these effects become obvious for many mud materials at temperatures of 300F or higher. It is understood that hydrolysis of starches, depoly-merization of certain organic thinners, or irreversible chemical reactions (such as that of clay and lime) can affect filtration, viscosity and shear strength at less than 300F. However, the temperature level is not a serious point and in no way affects the precautions and techniques used in this study. An up-to-date review of the literature on high-temperature drilling fluids and the many variations was treated by Rogers'in 1963. EXPERIMENTAL REQUIREMENTS TESTING EQUIPMENT AND PROCEDURES With the advent of deeper drilling and increased demand for temperature-stable drilling fluids, new testing equipment and laboratory techniques were devised for the evaluation of drilling fluids subjected to elevated temperature and pressure. While the equipment has not been standardized, it is in widespread use. Milligan et al. Qescribe a filtration cell for determining the filtration properties of drilling fluids at temperatures in excess of 300F. They showed the effect of variations in temperature and pressure on oil and water muds filtered in the 300 to 400F range. The dynamic filtration apparatus described by Simpson6 permits the study of the filtration properties to temperatures of 350F for drilling fluids circulated over sandstone cores. Watkins et al.' describe the use of pressure bombs for studying the effect of prolonged periods of elevated temperature upon the gelation or solidification of drilling fluids. Chisholm et a1.' describe the use of a modified cement consistometer adapted for use in drilling fluid evaluations. A similar consistometer is used in this study, although the application and data-recording method have been changed. The consistency of a mud sample is measured by timing the movement of a soft iron bob which is magnetically moved up and down in the sample container.* Changer in the time of travel and the temperature of the mud at that moment are plotted with a two-point Brown Elec-tronik Recorder. A 10-in. chart with a speed of 4-in./hr is used. Fia.- 1 is a generalized internretation of the data ob-

Jan 1, 1966

By Ivor Jenkins

Processes employing 'controlled at-mospheres in the heat-treatment of metals and alloys are now well established on an industrial scale, and the general principles involved and the advantages to be gained in the use of the technique have received considerable publicity over a period of years. During this time the greatest emphasis has been on the establishment of the process in industry, the main effort being devoted to development work on various types of atmospheres, their useful fields of application and the design of suitable heat-treatment furnaces in which they are to be used. The various types of controlled atmospheres are fairly well standardized, but there still remains a considerable field for the investigation of related problems, in connection with both the gas-generating equipment and the surface chemistry of the heat-treatment of metals, especially in complex controlled atmospheres. This paper describes certain investigations of this nature that were carried out in England up to 1939. The development of processes employing controlled atmospheres has been asso-ciated to a very large extent with the heat-treatment of steels, both because of the major importance of steel in industry and the many diverse and dificult prob-lems of surface chemistry involved when steels of such a wide range of composition are heated in the presence of active gases. Controlled atmospheres such as disso-ciated and burnt ammonia or charcoal gas are used in the heat-treatment of low-carbon and high-carbon steels, but from certain points of view a suitable atmosphere generated by the partial combustion of city gas is to be preferred. Both the ammonia derivatives are comparatively expensive, and even if the burnt ammonia is regenerated, thereby reducing operating costs, the capital expenditure of the gas plant may make it prohibitive for the smaller type of furnace installation. Charcoal-gas generators are not without their operating difficulties especially those associated with the quality of the charcoal, clinker formation and the removal of carbon dust from the generated gas. City gas has the advantage of being comparatively cheap and "on tap" in most if not all industrial centers. The use of raw city gas as a protective atmosphere in the heat-treatment of steels has been described,' but it presents certain difficulties because of its complex composition and its explosive nature when mixed with air. These factors, together with the tendency toward sooting at elevated temperatures, arising mainly from the hydrocarbon gases present, all militate against its use as a protective atmosphere in industrial furnaces. The following analysis, based on the analyses of city gas in different localities in Great Britain, indicates the wide limits existing

Jan 1, 1948

By Ivor Jenkins

Processes employing 'controlled at-mospheres in the heat-treatment of metals and alloys are now well established on an industrial scale, and the general principles involved and the advantages to be gained in the use of the technique have received considerable publicity over a period of years. During this time the greatest emphasis has been on the establishment of the process in industry, the main effort being devoted to development work on various types of atmospheres, their useful fields of application and the design of suitable heat-treatment furnaces in which they are to be used. The various types of controlled atmospheres are fairly well standardized, but there still remains a considerable field for the investigation of related problems, in connection with both the gas-generating equipment and the surface chemistry of the heat-treatment of metals, especially in complex controlled atmospheres. This paper describes certain investigations of this nature that were carried out in England up to 1939. The development of processes employing controlled atmospheres has been asso-ciated to a very large extent with the heat-treatment of steels, both because of the major importance of steel in industry and the many diverse and dificult prob-lems of surface chemistry involved when steels of such a wide range of composition are heated in the presence of active gases. Controlled atmospheres such as disso-ciated and burnt ammonia or charcoal gas are used in the heat-treatment of low-carbon and high-carbon steels, but from certain points of view a suitable atmosphere generated by the partial combustion of city gas is to be preferred. Both the ammonia derivatives are comparatively expensive, and even if the burnt ammonia is regenerated, thereby reducing operating costs, the capital expenditure of the gas plant may make it prohibitive for the smaller type of furnace installation. Charcoal-gas generators are not without their operating difficulties especially those associated with the quality of the charcoal, clinker formation and the removal of carbon dust from the generated gas. City gas has the advantage of being comparatively cheap and "on tap" in most if not all industrial centers. The use of raw city gas as a protective atmosphere in the heat-treatment of steels has been described,' but it presents certain difficulties because of its complex composition and its explosive nature when mixed with air. These factors, together with the tendency toward sooting at elevated temperatures, arising mainly from the hydrocarbon gases present, all militate against its use as a protective atmosphere in industrial furnaces. The following analysis, based on the analyses of city gas in different localities in Great Britain, indicates the wide limits existing

Jan 1, 1948

By H. T. Hildage

ALTHOUGH Greater New York does not bear any resemblance to a great mining district, the mining operations that are being conducted in and about the city are both extensive and interesting in character. With regard to the extent, it may be mentioned that, at. present, there is more dynamite used in New York than in any mining district in the United States; that there are under construction about 38 miles of tunnel, and that 66 miles more are projected, most of which must be constructed in the near future ; that since 1902 at least 2,000,000 tons of earth has been removed in underground work, in addition to about 3,500,000 tons that has been removed in, open-cut in connection with tunnel-work, and many times this quantity that has been removed in excavating foundations for buildings not connected with tunnel-work; and that there are to-day probably more than 5,000 men engaged in mining-work in and about New York City. These undertakings include almost every operation connected with underground work, from exploration by means of trench and boring, to the sinking of large shafts and the driving of large tunnels through every kind of ground from hard rock to soft, semi-fluid silt and quicksand. It is proposed in this paper to give a general description of some of the methods and appliances used in the opening-up ,of a "mine" in a large city, and a brief description of some of the "mines" now being developed in New York, connecting as far as possible the methods described with the particular work for which they were designed, in order to give a general idea of the

May 1, 1907

Jan 1, 1967

By C. A. Wright

Since the adoption by the U. S. Bureau of Standards several years ago of specifications for standard 100- and 200-mesh sieves, frequent requests have been received that this Bureau test and certify sieves of other sizes than these. With a view to the adoption of a series of standard testing sieves which might be of use to all industries making fineness tests, this Bureau for two years has been studying the question of such a standard screen scale. Various scales that have been proposed were considered, and information was sought of representative firms in the various industries interested as to their requirements. Manufacturers of sieves have also been consulted as to the desirability of different screen scales and the practicability of their manufacture. As a result of this study of the question, a conference was called at the Bureau of Standards, Apr. 20, 1916, of representatives of various committees of the American Society for Testing Materials, American Society of Civil Engineers, American Institute of Mining Engineers, American Foundrymen's Association, Mining and Metallurgical Society of America, American Water Works Association, American Institute of Metals and the American Spice Trade Association; also representatives of the Committee of Revision of the U. S. Pharmacopæia, the U. S. Geological Survey, the U. S. Bureau of Mines, the U. S. Office of Public Roads and Rural Engineering, the U. S. Office of Grain Standardization and the U. S. Bureau of Standards; also representatives of a number of private firms engaged in industries in which sieves are used, such as the glass, the drug milling, the abrasive, the asphalt, the mining, the spice, the chemical, and the graphite industries; also representatives of the firms in this country manufacturing wire cloth and sieves. This Conference, after considering the various screen scales either proposed or now in use, adopted as a Standard Screen Scale that given in Table 1, and recommends that it be adopted generally by scientific,

Jan 1, 1918

By AIME AIME

NO FEATURE of the annual meeting is considered more important at Institute headquarters than the assembly of delegates from the various local sections and divisions. There the president of the Institute and other officials may learn at first hand what the members are thinking and doing in every part of the country, and the delegates, in turn, may find that head- quarters is not a group of more or less cold-blooded New Yorkers whose primary function is to send out annual bills for $15. This year, the section and division delegates required three sessions to thresh out the matters of common interest: Monday morning and afternoon and Thursday afternoon. They were also guests of the Institute at the Directors' dinner on Tuesday night, and at the Directors' meeting afterward.

Jan 1, 1932

By N. A. Gjostein

The real and apparent dependence of the surface self-diffusion coefficient, Ds, of gold on crystallo-graphic orientation has been investigated by isolated scratch smoothing and grain boundary grooving experiments. No systematic variation of Ds with orientation was found along the [100] zone. In view of the experimental scatter in these results, however, only aniso-tropy ratios, p, greater than -1.3 would be detectable. Anomalously low values of Ds were found on the [0ll] and [110] zones when the diffusion direction lies along (the scratch or grain boundary groove is perpendicular to) these zones. By comparing these results with a previous y plot study of gold, it is hypothesized that this is not an intrinsic diffusivity effect, but rather it results from a decreased driving force for mass transfer at orientations where the y-plot curvature is negative and appreciable in magnitude relative to y. The characteristics of this type of anisotropy do not appear sEVERAL investigations1-7 have dealt with the anisotropy of the surface self-diffusion coefficient, Ds, of metals as measured by the decay of single or multiple to be in agreement with the hypothesis of fast diffusion along ledges in the surface structure. In certain cases the Fourier method of determining Ds, described in Paper I of this series9 was compared with the second moment analysis in order to determine whether or not the method of analysis affects the anisotropy ratio. While the type of analysis does influence the magnitude of the anisotropy ratio, this effect is not associated with the shape of the profile, but rather is connected with the iterative volume diffusion correction used in conjunction with the second moment analysis. It is further demonstrated that the volume diffusion correction can be too large by either method when the y-plot curvature effect is large. Certain orientations exhibit an unusual temperature dependence of Ds ; this is discussed in terms of the y-plot curvature effect and/or the influence of impurities on Ds . scratches in the surface. Depending on the system investigated, both large1"3'6'7 and small4'5 anisotropies in Ds have been found. Although adsorbed impurities undoubtedly play an important role in determining the magnitude of the anisotropy,8 there are other factors that can give rise to an apparent anisotropy in Ds, thus obscuring the true nature of an intrinsic anisotropy in

Jan 1, 1968

By J. R. Low, D. F. Stein

Single crystals of iron have been grown from three different lots of Ferrovac "E" of somewhat different chemical composition by the strain anneal technique. Using a technique to seed the crystal similar to Dunn's for silicon-iron, it has been possible to orient the crystals grown in both direction and plane of growth. Crystals having the plane of the strip oriented (100) , (110), (111), (112), (123), and (491) have been grown. The growth directions used have been [100], [110], 45 deg from a [110}, and various others of no specific crystal orientation. The usual dimensions of the crystals were 8 by 1 by 0.08 in. Attempts to grow crystals were about 90 pct successful. METHODS of growing single crystals of high purity iron have been reported in the literature.1-4 However, each of these methods was not completely reliable when used on materials having slightly different chemical composition and in some instances a small number of successes were obtained using identical materials. Except for the method used by S. Dohi and T. Yamoshita,1 it has not been possible to reorient single crystals of high purity iron to give any desired orientation. The method to be described has made it possible to grow single crystals from three different lots of material having different compositions, and to orient the crystals with respect to growth direction and surface. STARTING MATERIAL The material used during this investigation was a vacuum melted high purity iron marketed by the Vacuum Metals Corporation designated Ferrovac "E." Three lots of Ferrovac "E" having the following composition were used with equal success: The compositions listed are those of the as-received material; and they may have been modified before the growth of single crystals. Analysis of heat B just before growth and after growth revealed that the heat treatment prior to growth did not change the carbon content, but the oxygen content was changed from 0.0092 pct to 0.0034 pct and the nitrogen content from 0.0003 pct to 0.0001 pct. After growth of the single crystals, the carbon had dropped to 0.001 pct. None of the heat treatments would be expected to change any of the other impurities very markedly. Heat C would be expected to have a metallic impurity content similar to heats A and B. PROCEDURE Ferrovac "E" iron which had been obtained in bar form having a diameter of about 1 in. was rolled into strip for growing single crystals. By passing the 1-in. bar through a cold rolling mill several times, it was reduced to a strip 0.15 in. thick. The strips obtained were then cut into suitable lengths for heat treating (about 9 in. long), annealed at 925°C for 2 hr in dry hydrogen and water quenched. It was then necessary to bake the strip at 200°C for 24 hr in air in order to prevent cracking during further rolling operations. While it was possible to cold roll the 1-in. bar directly to the desired 0.080-in. strip, the intermediate anneal was used because the strip so obtained produced better single crystals. The strip obtained by rolling the 1 -in. bar directly to 0.080-in. strip produced single crystals having a large number of occluded grains. Experiments showed that the optimum reduction in area by rolling prior to the growth of single crystals was about 50 pct. Attempts to grow single crystals from material that had been reduced less than 40 pct were unsuccessful presumably because the matrix did not possess the critical amount of texture necessary for growth. The strip obtained after the rolling operations had very irregular edges which were ground to give a strip with uniform dimensions. The strip was then annealed at 825°C for 3 hr in hydrogen and furnace cooled. Fig. 1 illustrates the grain size obtained. A temperature of 940°C was used for the annealing temperature on one group of strips

Jan 1, 1962

The problems confronting the development of Latin America's mineral resources have hinged largely on the political and economic climates-in short, the investment climate--existing and often changing in each nation. .The attractions and risks confronting today's investors in such mineral developments have been described and debated to considerable length during the past two decades, the arguments pro and con colored by the previous experiences incurred by the would-be investor, whether company or individual. In an effort to shed light on the investment climates existing today throughout Central and South America, the Council of Economics brought four experts together at the AIME Annual Meeting last March to give their views on this subject.

Jan 7, 1966

By Charles H. White

METHODS in colorimetry are based on the assumption that the intensity of the color of a definite volume of solution is directly proportional to the quantity of the color-producing substance' present. In the preparation and examination of colored solutions there are three ways in which the depth of color may be varied. These variables are; (1) the quantity of the coloring matter, (2) the quantity of the solvent, or the dilution, and (3) the thickness or depth of that portion of the solution examined. With these three variables as a basis, three general methods in colorimetry have been devised, all of which have been used in the determination of carbon in steel. In the first method, the quantity of the solution is kept the same for both the unknown steel and the standard, and the sections compared are of equal thickness, while the quantity of the standard is varied until the color obtained is of the same intensity as that produced by a definite quantity of the unknown steel. In laboratories where this method is used there is pre¬pared and kept for permanent use a series of solutions with varying amounts of the standard, representing the percentages of carbon from the lowest to the highest demanded in that laboratory. These standard solutions are kept in bottles, or test-tubes of equal diameter, and are arranged in series from the faintest to the most intense color, so that it is a simple matter to find the place of the unknown steel in the series, when the solution is of a definite volume and is contained in a tube of the same diameter as the standard tubes. In the second method, equal quantities of the standard and of the unknown steel are dissolved, the standard is diluted to a definite volume, and the solution of the unknown steel is di-

Sep 1, 1906

By Cadwallader Evans

MY endeavor in this paper will be to tell something of the accomplishments and current problems of the anthracite producer and to suggest some of the avenues for technical development that seem to me to be the most necessary and likely to bear fruitful results. The several subjects, that I find of most interest will be taken up individually with brief reference to the future trend. Underground Mining and Loading ?In this field great progress has been made in the last twenty years, beginning with the introduction of the scraper system. The electrical hoists for the operation of scrapers have been improved, and give little trouble, but there is an open field for the improvement of the auxiliary apparatus, particularly in the application of roller-hearing sheaves to the guiding of scraper ropes. Also notable in the last six or seven years is the introduction of shaker chutes, so that far more anthracite is now loaded over them than by scrapers. This trend should continue to be manifest, particularly if those who are looking ahead and who are charged with the development of this specialty continue constantly to study and improve the mechanical design of their shakers.

Jan 1, 1938

By Edward H. Robie

THE registration badges gave out, there were not enough programs, the Pioneer Hotel's rooms were insufficient, and some hundred applicants for banquet tickets had to be turned down at the Institute's Regional Meeting in Tucson, Nov. 1-5. Minor inconveniences these, however, occasioned by the fact that, optimistic as they are in Arizona, about half again as many partook of the week's activities as were expected. For this, the local program committee can be blamed-both the technical and social features were too attractive in quantity and quality. Seriously speaking, though, the Institute has probably never had a more successful Regional Meeting than this one. It being the first that has been held in Arizona in 22 years, no effort was spared to make it the distinctive gathering that it was.

Jan 1, 1938

By Richard T. Newcomb

Federal and utility industry research has largely ignored coal beneficiation techniques in the implementation of SOx control. This paper accepts the hypothesis that beneficiation cum scrubbing is the cheapest way for the vast majority of seams in the eastern coal provinces to comply with standards. Comparisons are based on point estimates of average beneficiation costs from a model of coal preparation (COBET) designed to simulate four levels of cleaning. The paper describes how economic theory can be applied to derive econometric supply functions from actual data on the geology of minable seams, washability and technical constraints. West Virginia is taken as an example of a producing region. Spatial supply functions are derived empirically from the engineering model simulations.

Jan 1, 1977

By Benjamin Talbot

(New York Meeting, February 1913.) THE problem of segregation and cavities in steel ingots is a subject which has given and is still giving metallurgists, en¬gineers, and operators matter for serious consideration.. This question has come more into prominence lately in the United States, clue largely to the desire of railroad engineers to secure a better rail than they have obtained in the past, as the service they demand is increasing in severity; and no doubt manufacturers will be able to meet what is required of them. The rails here are as good as those made in other countries, but the conditions of service and the extremes of climate are more severe and consequently more breakages occur. Various reasons have been advanced to explain why rails may not be as good in quality to-clay as in the past. Some engineers consider that modern methods of manufacturing, designed chiefly to obtain large output, tend to reduce the standard of excellence of more deliberate methods. Others think that 4-ton ingots are worse than those of 2 tons. Again, it is .stated that the 100-ton heat in one ladle is too large, and is a :step in the wrong direction in casting. My experience upon the question of the size of the ingot is that in rolling rails of from 85-to 100-lb. sections, the range of ingot is only practically such that the difference in the size does not help in the question of segregation, cavities, or blow-holes.

Jan 4, 1913

By C. H. Jr. Herty

IRON oxide .(Fe0) plays an extremely important part in the manufacture of steel. In the open-hearth furnace and the Bessemer converter it is the chemically predominant compound and controls to a large extent both the operation of the furnaces and the composition and quality of their products. Almost all of the refining action is carried out through the medium of FeO, which oxidizes carbon, manganese, silicon, and phosphorus. At the end of any open-hearth or Bessemer heat the steel contains dissolved iron oxide, which must be wholly or partly eliminated. The type of deoxidation product depends on the amount of dissolved iron oxide and on the deoxidizer used. After the heat has been deoxidized and while it is being teemed, iron oxide diffuses from the ladle slag into the metal, causing losses of deoxidizer and increase in iron oxide content of the steel. It is generally believed that non-metallic inclusions are responsible for a great many failures of steel in service and for decreased yield of steel during rolling. The basis of most non-metallic inclusions is dissolved iron oxide. This investigation was undertaken in order to determine the amount of iron oxide that will dissolve in iron under various conditions. Steel-making slags are complex and it has been thought best to determine solubility under simple slags as a first step. The study is being continued under slags whose compositions approach those of operating. slags.

Jan 1, 1928

By C. R. Fettke

In 1914, the officials of the Brundred Oil Corpn., faced with the problem of introducing new methods to increase production in the old and nearly depleted pools of Venango County, became interested in the Smith-Dunn (Marietta) process which was at that time being tried out in southeastern Ohio and which was already yielding very encouraging results. A license to use the process in Pennsylvania was secured from the owners of the patents. These patents were later declared invalid. The method was first used in Pennsylvania on a property consisting of about 434 acres, of which 300 are productive, at Hamilton Corners, 15 miles northwest of Oil City, in Cherry Tree and Oakland Townships, Venango County. The producing horizon is the First Sand of the Venango Group. A small oil pool was opened up in this vicinity in 1904. By July, 1916, when the compressed air was first introduced to restore pressure, the production had dropped to a point where it was no longer possible to continue profitable operation. From that time until March, 1927, over 100,000 bbl. of oil have been recovered from the tract. The property is being operated at present by the Brundred Oil Corpn. and LUX. The 1926 production, amounting to 10,650 bbl., was only 400 bbl. short of the maximum reached during any year of the 10-year period that the process has been in operation. Inasmuch as the Hamilton Corners pool is the first one in Pennsylvania in which the Marietta process was tried out, and the one in which it has been longest in continuous operation, considerable interest attaches to the results obtained. Through the courtesy of H. D. Brown and W. J. Brundred, officials of the Brundred Oil Corpn., all their data on this operation were made available to the writer in connection with an investigation of rejuvenation methods in the State for the Pennsylvania Geological Survey. Stratigraphic Position of the Producing Sand The producing sand at Hamilton Corners is encountered at depths of from 364 to 560 ft., depending on the location of the well and the topog-

Jan 1, 1928