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By H. R. Shidel

THIS paper summarizes the results obtained from the preliminary cementing of wells in an effort to cut off the bottom water. The object of this work was two-fold: (1) To prevent the oil sand from becoming flooded. (2) To plug off bottom water, thereby preserving the individual well and reclaiming production. Valuable suggestions and help have been given by the following named: Messrs. Kyle and La Velle, of the U. S. Bureau of Mines; Magnolia Petroleum Co.; Freed Oil and Gas Co. The cementing work was carried out under the personal supervision of L. J. Snyder. In an unpublished paper on the "Water Problem in the Augusta Field," S. K. Clark reaches the following conclusions: (1) That the great amount of water present is bottom water, occurring in the Varner sand, the main producing or the 2500-ft. horizon. (2) That the only striking connection between structure and water is in the area of the marked fault on the Ralston, E. C. Varner, and F. Varner leases in sections 8, 9, 16 and 17. (3) That the oil occurs in porous streaks, generally separated by fine-grained, well cemented sand, which is barren. Possibly two, or three such pay streaks may be found. That under a pay, fine-grained sand occurs, which is presumably barren at the time of drilling, but soon reveals water. The writer takes partial exception to the last point, because well defined shale, slate, lime, or hard sand breaks have been encountered in a great many cases, separating the pay streaks under which water is often found. This is not an invariable occurrence, as cases have been noted when the oil has been followed immediately by water in the same stratum. In an effort to overcome the water menace, the following methods of plugging were tried: (1) Plugging with wood, lead, and limit plugs. (2) Plugging with sand pumpings.

Jan 10, 1918

By S. M. Marshall, B. M. Bird

For a number of years European investigators have used laboratory methods of predicting the probable strength of coke made from coal, and recently several investigators in the United States have reported the use of various tests for this purpose. There is at present no method accepted as standard, however, nor is there even agreement as to the general type of test that should be used. Furthermore, because the details of most of the tests have not been worked out carefully, one investigator can not hope to duplicate the work of another. The extension of coke manufacture to new localities in the United States, and the increasing need for cokes of exceptional qualities made from the most economical mixtures, made it desirable to have some simple laboratory test which will determine whether given coals, alone or blended with other coals, are more satisfactory from the standpoint of coke strenpth- than others of different cost. The work described herein has resulted in the development of a simple laboratory test which, it is believed, can be generally adopted in coal laborat,ories, and which will give concordant results even though performed by different investigators in different laboratories. The general method of predicting whether a coal or a mixture of coals will produce a strong coke, resistant to crushing and shattering, has been to correlate the known strengths of the cokes produced in commercial ovens with some measurable constituent or with some property of the coals, and then to use the relationship so found for forming an estimate of the coking strengths of coals unknown. Several such correlations have utilized the percentages of the various ultimate constituents of coal, such as the oxygen content and the hydrogen-oxygen ratio;(39)§ other correlations have involved the proportion of a, B and r com-pounds, (17,21,30c) or of "oil and solid bitumens."(16,30) Also a relationship has been traced between the coking properties of coal and the rate of change of the resistance offered to the flow of an inert gas by fine particles of the coal while being slowly heated. (11,176) But the most general corre-

Jan 1, 1930

By Edward Hart

The specimen of glazy iron used for analysis was highly characteristic in appearance. It was made at one of the furnaces of the Glendon Iron Works, working a light burden of ore with a highly silicious cinder. There are very few records of analyses of this variety of iron. I have been able to find but the two given by Bell, and I add these to my analysis for comparison. Bell. 1. 2. Iron,......89.47* 88.18 90.70 Carbon, combined,.... 0.00 0.79 0.71 Graphite,......2.88 2.59 2 68 Silicon,......5.47 5 13 5.13 Manganese,.....1.54 0.77 0.56 Sulphur,......0.04 0.17 0.23 Phosphorus,.....0.60 1.12 1.12 Titanium,.....- 0.26 0.18 Calcium,......0.00 0.22 0.20 Magnesium,.....0.00 0.06 0.03 100.00 9929 101.54

THERE is at least one concrete indication that Soviet Russia's two most important iron ore producing centers are seriously depleted. While keeping in mind Russia's penchant for reverse propaganda, one piece of evidence indicates that Magnitugorsk in the southern Urals and Krivoi Rog in the Ukraine have been mined to a point where lower grade ores are being recovered. An article in Pravda, Soviet newspaper, by I. P. Bardin. a Russian metallurgist, says that ore presently mined must undergo an expensive enriching cycle before it can be used in blast furnaces. Com- pounding Russian metallurgical troubles is the low quality of coking coals. High ash and sulphur content typifies the coal Badin talks about. Coal from the Ukraine, Eastern Siberia, Kazakhstan, and the Far East requires extensive treatment before it can be used, according to the article in Pravda.

Jan 7, 1953

By R. C. Canby

The difficulty of exact neutralization by ammonia of the acid solution obtained in the determination of arsenic by the method of fusion with carbonate of soda and nitrate of potassium, led me to try the effect of neutralization by oxide of zinc. I obtained most satisfactory results, and found a great saving of time. The oxide of zinc being added in excess, there is no delicate testing with lit? mils paper and tedious alternate adding of dilute ammonia arid acid until the proper point is reached. The excess of oxide of zinc, too, seems to hold, from the filter, the gelatinous silica and alumina, which are usually precipitated upon neutralization, and thus to render the washing of the precipitated arseniate of silver almost invariably much more rapid. Except the substitution of the neutralization by oxide of zinc for the more tedious method by ammonia, the details of the process are practically the same as those published by Mr. Richard Pearce, of Argo, Colorado (Proceedings of the Colorado Scientific Society, vol. i.), who shows what very accurate results can be obtained by the fusion process. I have made numerous tests of comparison between the two methods of neutralization, and find that those by the oxide of zinc agree almost exactly with the old method. Increasing the quantity of nitric acid, even to considerable excess, to be neutralized by the oxide of zinc did not affect the precipitation of arseniate of silver. The process may be outlined as follows : Take 4 to 1 gramme finely pulverized ore, and mix in a porcelain crucible with eight to ten times its weight of a mixture of equal parts of carbonate of soda and nitrate of potassium (Kerl. Metallurgische Probirkunst gives 4 to 5 nitre to 14 soda). Gradually bring to fusion and keep so, three to five minutes. Cool. Disintegrate in hot water. Filter and wash with hot water. Acidify the filtrate with nitric acid, and boil to expel carbonic acid and nitrous fumes. Cool. Add an excess of an emulsion of oxide of zinc. The bottom of the beaker should have quite a layer of oxide of zinc, after stirring.

Jan 1, 1889

By R. H. Card

THE geophysicist is interested greatly in the resistivities of different formations or parts of the earth's crust; sometimes he is interested in a single figure in the nature of an average, or what may be called the effec-tive resistivity, of all the formations or parts of the crust at a given location to a certain depth. Conversely, the engineer whose work is concerned with the coordination of power and communication lines in such a manner as to avoid electrical interference between these two types of facilities is concerned very much with this effective resistivity; to a lesser extent he is interested in the resistivities of individual forma-tions. In connection with his work the coordination engineer often estimates the effective resistivity; of the earth from measurements of the mutual impedances of lines; in other instances he derives front measure-ments of a different type the resistivities of different layers of the crust and synthesizes these to obtain an estimate of the effective resistivity. In connection with problems concerning the coordination of power and telephone lines, measurements from which earth resistivities can be estimated have been made at many points in the United States by the American Telephone and Telegraph Co. and its associated companies, in cooperation with various power companies and with railroad companies having electrified sections of line. Other such measurements have been made by the Joint Subcommittee on Development and Research of the Edison Electric Institute and the Bell Telephone System. A study has been made of the correlation of these data with the ages and types of materials of the strata of the earth's crust at each of the test locations. The purpose of this study has been primarily to provide information to assist in predicting the order of magnitude of effective resistivities to be used in the preliminary consideration of problems con-cerned with the coordination of power and communication lines. To make the results of such a study, most useful, it is essential that the geo-logical data to be secured when such a prediction is wanted be readily obtainable. Data on the ages of strata and the types of materials com-posing geological structures can usually be obtained, therefore particu-

Jan 1, 1937

By H. M. Otte, A. L. Esquivel

A new leasl-squares method is Presented for determining lattice parameters of hexagonal or tetragonul structures. The method is adapted for use on electronic computers and involves a reiterative procedure. The correction factor employed raries linearly with the lattice parameter, a (determined from the Brag, angle). In contrast, Cohen's method and recent modifications of it use a correction factor that varies incersely as the squure of the lattice paramneter, a. While the recent modifications attempt to improve the precision of the extrapolated lattice parameter, a, (or-cu). by stressing the importance of the weighting factor. the present approach emphasizes the need for choosing the correct extrapolation function. A comparison between the present method (the Linear method) and Cohen's method indicates that the Linear method may be more appropriale in certain cases. through a priori no critertion appears to he available for making a chorce between the methods. The size of hexagonal and tetragonal crystal lattices is determined by two parameters, a, and c,. Although in principle the two lattice parameters can be determined independently from reflections for which h - k = 0 and 1 = 0, respectively, in practice this may be inconvenient (because of the angular positions at which these reflections may occur) or not easily possible (because of low intensity). Furthermore, if a high precision or accuracy is required, the limited number of reflections of this type available, particularly in the high-angle region, is not sufficient for the necessary corrections (mainly due to absorption) to be determined with accuracy. Several methods1-7,11-13 have been proposed employing all reflections, to obtain the optimum values, a. and co, either by a trial and error procedure or a least-squares fit. Of the latter method, cohen's5 is the best known one since it provides explicit expressions for the optimum a. and c,. However, Cohen's method is only strictly valid if an extrapolation function is used that varies linearly with l/a2 or lie2 (see Section 3), a requirement that does not appear to be generally appreciated. On the other hand, all the better known and more widely used A recent trial and error method was proposed by Massalski and King8,7 who computed extensive auxiliary tables of axial ratios vs the functions A = [(4/3)(h2 + hk +k2) + l2+(a/c)2] and C = A(c/a)2 used in computing a and c values from the observed Bragg angles. These values of a and c were then plotted against a function which permitted linear extrapolation. As a criteria; for the "optimum" values, Massalski and King rely upon a visual fitting of the line through points representing reflections of low 1-index points to compute the extrapolated value of ao and high 1-index reflections to obtain CO. The successive computations and graphical plotting required to reach the "optimum" value are quite lengthy and tedious even on a desk calculator and no quantitative assurance is obtained of having in fact selected the optimum value.* If the method of Massalski and King is used on an electronic computer, then their published tables become redundant and a least-squares fit becomes a natural selection for the choice of optimum values. Such an approach will be called the Linear method. For work now in progress on the effect of certain physical variables on the lattice parameters of hexagonal crystals, it has become essential to determine the confidence limits of small changes in the lattice parameters. Since extrapolation functions that varied linearly with a and c actually also appeared to vary linearly with l/a2 or l/c2 when tested against published as well as our data, a comparison of Cohen's method and the Linear method was considered desirable (Sections 3 and 4). For the latter method an electronic computer was required since a reiterative procedure to obtain the optimum ao and co values had to be employed. The purpose of this paper is to describe the principles of the Linear method, illustrate its application, and compare it with Cohen's method. 1) THE LINEAR METHOD The standard practice in obtaining the lattice parameters in the Debye-Scherrer method is to

Jan 1, 1965

"WELFARE…Welfare endeavor in connection with both the metal and the coal mines of Utah has shown gratifying progress during recent years and both the operators and their employees are deserving of much credit for the efforts put forth to better living, working, educational and receational conditions in most of the mining camps of the state.In the older metal mining camps of Utah, where the towns are incorporated and independent of the mining properties operating in the vicinity, less opportunity is pre¬sented for the companies to exercise efforts looking towards improved welfare conditions than is the case of camps located on company ground and under the full control of operators.Even in such camps, however, as illustrated in Bingham, the companies can do much to better welfare conditions. In this camp the Utah Copper Company has spent $800,000 since 1 920 in the erection of modern brick cottages, apartment houses and the Gemmell Memorial Club. The cottages and apartments have every convenience to be found in up-to-date city homes. The Gemmell Memorial Club, erected and equipped at a cost of $1 75,000, was provided by the company for the benefit of the Utah Copper Company employees living in the canyon and has been made the recreational center for the camp."

Jan 1, 1925

By R. S. French, W. R. Hibbard

FOR tensile deformation, if the stress value is defined by the ratio of the load to the actual area, and the strain value by the natural logarithm of the ratio of the immediate length to the original gauge length of the sample, the resulting data when plotted with logarithmic coordinates result in a linear relation extending from the initial plastic yielding through the maximum load and in some cases, such as for copper and brass, to fracture'.'. The normal form of the curve, therefore, is a parabola, satisfying the following equation: S = Kem [1] where S and e represent true stress and strain, K is a constant, and m is a coefficient evaluating the slope of the curve and designated therefore as the strain hardening coefficient. Hollomon² has reported that this coefficient is a function of the yield strength as effected by grain size in alpha brass, and the carbon content and heat treatment of steel. In the case of steel, the value of the proportionality constant is a function of the carbon content. It was further shown in that paper2 and also by Low and Prater -hat, if the power relation between stress and strain remains valid, the strain hardening coefficient m, is equal to the strain at the maximum or necking load. Thus, an added significant feature is that this coefficient may serve as an index of the capacity for deformation prior to localized necking and subsequent fracture, e.g. drawability. The constant K may be defined as the strength of the material at unit strain. Together the K constant and the m coefficient describe an alloy's physical properties as far as strength and ductility are concerned for a particular yield strength and, in the case of steel, a particular carbon content. The work of Lacy and Gensamer4 gives data on alloy ferrites from which very close estimates of the strength of ternary and higher iron alloys have been made. It was the purpose of this investigation to develop similar data for commercial copper base alpha solid solution alloys. Preparation of Specimens Commercial binary alloys of copper with aluminum, beryllium, cadmium, nickel, silicon, tin and zinc were investigated. In addition, laboratory castings were made of a 1 pct silicon alloy and a 2 pct aluminum alloy to complete these particular series. Two types of copper were used, oxygen free OFHC and tough pitch FC. The analyses of these alloys are shown in table I. Standard ASTM sheet tensile specimens were used to determine the usual physical properties of each alloy and to obtain stress data at strains from 0.0005 to 0.01. Small (1/4 in. x 3 in. x tk.) samples

Jan 1, 1951

By E. R. Gilbert, D. E. Munson

Creep of copper under 75 to 1.50 kg per sq cm stresses at temperatures near the melting point was found to he a complex reaction controlled by three mechanisms acting in parallel. In order of appearance with decreasing temperature, the auerage activation energies, Qc , are 168, 79, and 24 kcal per mole. Stress dependence of the minimum creep rate was found to he an exponential for the two high-Qc processes and a power law for the low-Qc, process. Transition of control occurs from one mechanism to another. The relative transition temperature depends upon the applied stress, and the range oiler which the transition occurs depends upon the difference in the activation energies of the mechanisms. The creep behavior at high temperature is explained by the climb of dislocations through thermally or mechanically formed jogs, CREEP in pure fcc metals at temperatures in excess of one half the absolute melting point is normally controlled by dislocation c1imb.1,2 A climb model which seems applicable, according to an extensive analysis of data,3 was derived by Weert-man.4 This model assumes jog-saturated dislocations and predicts an activation energy, Qc, nearly equal to that for self-diffusion, USd. Although the requirement of jog saturation is restrictive, agreement between theory and experiment seems adequate. Many other theoretical treatments, including an early model by Mott,5 include detailed consideration of jog formation as an initial requirement for climb. These models predict activation energies for creep which differ from those of self-diffusion. Seeger6,7 postulates an observed activation energy related to the stacking-fault energy. Thus, Usd <Qc<5Usd + Uj where Uj is the jog-formation energy. Seeger incorporated qualitatively the influence of the relative numbers of thermal and athermal jogs. Expanding this concept, Shoeck8 explicitly states a function based on formation mode and relative numbers of vacancies: e r ci exp {-uf/k T} exp {-Um/k T} [ 1 ] where Uf and Um are energies of vacancy formation and migration, respectively. The concentration of jogs, Cj, depends upon the manner of jog production. For intersection jogs, Cj is not sensitive E. R. GILBERT, Junior Member AIME, formerly with De- to temperature; for thermal jogs, Cj is proportional to exp {—Uj /k T}. Schoeck regards each mode as a distinct mechanism; therefore, the mechanisms may act together.299 The diversity predicted by theory, surprisingly, has not been substantiated by experimental results. A significant investigation must include the extremes in stacking-fault energy. Extensive creep studies of aluminum10 and nickel,11,12 high stacking-fault energy metals, have been made. Comparable studies on a low stacking-fault energy metal, such as copper, have not. It is the purpose of this paper to report the results of an investigation of the creep of copper under conditions which favor thermal jogs. EXPERIMENTAL Cylindrical compression creep specimens (0.240 in. in diameter by 0.400 in. long) were machined from cold-drawn rods of electrolytic tough-pitch copper containing 0.0007 Mg, 0.002 Fe, 0.001 Ni, 0.0005 Ag, Cd < 0.005, and Pb < 0.005 wt pct impurities. Undetected spectrographically was a nominal 0.04 wt pct 0, which occurs as a Cu2O constituent distributed discontinuously at grain boundaries. Vacuum annealing at 900°C for 15 min produced a stable 0.03-mm average grain diameter. Testing was carried out using apparatus similar to that described by sherby,13 modified by enclosing platens and a push rod in a vacuum cylinder. Normally this arrangement resulted in pressures less than 10 Only a slight surface tarnish, less than 0.0005 in. in thickness, occurred during the test. The applied stress, corrected for atmospheric pressure, was maintained within 2 pct of the desired true stress by the addition of lead shot at fixed strain increments. Creep strain was measured with dial gages as a relative displacement of the upper and lower platens; accuracy of measurement was 0.0001 in. Two creep-test methods were used, the differential or cyclic temperature14 and the isothermal, to obtain creep data at stress levels of 150, 100, and 75 kg per sq cm over the temperature range of 620° to 1032°C. Minimum creep rates were used from both test methods; this was considered proper because comparable temperature tests or cycling to the same temperature gave the same creep rate, within experimental error. The cold vacuum test chamber, with the unstressed specimen in place, was heated to temperature by placing a preheated furnace over the chamber. Temperature equilibrium was attained within 30 min. For the cyclic tests, the stress was removed during the 5 to 10 min necessary to effect the temperature change and re-

Jan 1, 1965

Organization Place Date 1917 American Institute of Architects Philadelphia., Pa. Dec. 26-29 American Society of Mechanical Engineers New York City. Dec. 4-7 American Mining Congress State Chapter Phoenix, Ariz. Dec. 26-29 1918 American Society of Civil Engineers New York, N. Y. Jan. 22-25 American Institute of Mining Engineers New York, N. Y. Feb. 18-21

Jan 12, 1917

By D. A. Martin, Laird Crocker, W. I. Nissen

The Federal Bureau of Mines has developed a process for removing SO2 from stack gases. The process comprises absorption of SO2 in an. aqueous solution of sodium citrate, citric acid, and sodium thiosulfate, followed by reaction of the absorbed SO2 with H2S to precipitate sulfur and regenerate the citrate solution for recycle. A pilot plant was operated at The Bunker Hill Co. lead smelter in Kellogg, Idaho, to assess the feasibility of using the process for flue gas desulfurization. Nominal capacity of the pilot plant, which treated .tail gas from the lead smelter sintering furnace, was 1699 standard meters cubed per hour (15 degrees celsius) of 0.3- to 0.7-percent-SO2 gas yielding about 272 net kilograms of sulfur per day. The pilot plant was operated for about 4500 hours and produced more than 45 net tonnes of sulfur. The operation demonstrated that (1) more than 95 percent of the SO2 could be removed from the lead smelter sintering furnace tail gases, (2) regeneration of the citrate solution with H2S and precipitation of sulfur in conventional stirred vessels was readily controlled and highly efficient, (3) the precipitated sulfur could be continuously recovered as a 99.5-percent-pure product by kerosine flotation and melting, and (4) the 77- to 79-percent-H2S gas used for sulfur precipitation could be readily produced from pilot plant product sulfur, natural gas, and steam. Projected operating costs, including capital charges, for a citrate plant, installed at a 118 000-tonne-per-year lead smelter and treating 49 271 standard meters cubed per hour of lead smelter sintering furnace tail gas, are estimated to be $384 per tonne of sulfur.

Jan 1, 1976

By Allan D. Taylor

INTRODUCTION From the designer&apos;s view, the installation starts with the first definition of the orebody, and progresses through a long and complex development. The design is affected not only by the characteristics of the ore, but by all of the personalities and events of the project during its development. The following discussion attempts to touch on the most important aspects which define the context in which the designer must work in apply the do&apos;s and don&apos;ts. That context is the basis of the viewpoint. WHAT CAN GO WRONG The Project Is Going Over Budget This is a common and serious concern to the plant designer. The Project Falls Behind Schedule Another common and disturbing condition with which the plant designer must cope. Some Equipment Fails to Perform This can be due to either faulty equipment or operating deficiencies. It can be the result of a wide variety of causes, but the designer will be an interested party in the search for the cause and the cure. The Plant Isn&apos;t Flexible Enough Sometimes a plant will handle some or even most of the ore satisfactorily but is unable to treat another type properly. This can be a significant problem. An example might be a case where low capacity of a cyclone feed pump makes it impossible to accompany an increase in grinding mill throughput with a corresponding increase in dilution water. This could lead to an increase in cyclone feed density, and a loss in product grade or a limit on the plant capacity. Spillage And Cleanup Are Excessive This is one of the most common and annoying defects in metallurgical plants, and one for which the designer can rarely delegate blame. Maintenance Is Excessive Another common complaint in new plants, and also one for which the dedesigner must accept most of the responsibility.

Jan 1, 1982

By G. R. Purdy, J. G. Parr

The intermetallic compound Ti2Co was studied by X-ray diffraction and metallographic techniques. The phase occurs off stoickzometric composition, with its greatest variance at high temperature. The solubility limits of the phase have been cletermined, and an amendment to the titanium-cobalt phase diagram is suggested. THE first intermetnllic compound to appear at the titanium-rich side of the titanium-cobalt system was found by Laves and wallbauml to be Ti2Co. They described this compound as isomorphous with Ti2Ni and Ti2Fe, and demonstrated that it had a face-centered-cubic structure with 96 atoms per unit cell. This contention is supported by the work of Duwez and Taylor2 and Orrell and Fontana3 who also determined the lattice parameter to be about 11.30A. Rostoker4 believed that Ti2Co did not exist, and that the phase considered by the other workers to be Ti2Co was Ti,Co20. However, Orrell and Fontana determined oxygen and nitrogen contents and found that their alloys did not contain sufficient of these elements to produce significant quantities of a stoichiometric oxygen compound. The present investigation was initiated to determine the composition limits of the phase Ti,Co.

Jan 1, 1961

By H. W. C. Prommel

While Utah remains an unimportant factor in oil production, exploratory drilling was carried on in six widely separated areas, extending from the southwest to the northeast corner of the state. One new gas field, the Last Chance or Starvation Creek anticline in Emery County, and two new gas horizons in the Clay Basin field of Daggett County, were thereby discovered during 1934. Exploratory Drilling South Central Utah Emery County—Last Chance Anticline.—The test of the Ramsey Petroleum Corporation in sec. 18, T.26S., R.7E., on the apex of this anticline (vert. closure 700 ft.; area within closing contour line, as mapped by U.S. Geological Survey, 26,000 acres) encountered gas in the Moenkopi formation of lower Triassic age at depths ranging from 2530 to 2863 ft. The total thickness of sandstone, sandy shale and -limestone beds in which gas was encountered is approximately 50 ft. The well was tested at a depth of 2755 ft., gaging 21,000,000 cu. ft. of gas, R.P. 410 lb. The well is being plugged back to the lowest gas horizon at 2771 ft. from a total depth of 3168 ft. Gas from this well probably will be used for the drilling of a second well structurally lower, to test the oil possibilities of the Moenkopi formation as well as of the upper and lower Pennsylvania formations, of which the latter so far remains untested in South Central Utah. The well was not drilled deep enough to determine more definitely the western margin of the petroliferous Paradox Basin of lower Pennsyl-vanian age of southeastern Utah. Woodside Anticline.—This field, lying immediately northeast of the San Rafael swell, contains, according to maps of the U.S. Geological Survey, 8380 acres within its lowest closing contour line 700 ft. below the apex. A well was drilled by Utah Oil Refining Co. at the apex in sec. 12, T.l9S., R.l3E., during 1924. Gas was encountered in the Moenkopi and Kaibab formations of Triassic and Carboniferous (Permian) age respectively. The flow is estimated at 21,000,000 cu. ft., R.P. 900 lb.,

Jan 1, 1935

By L. E. PORTNER

INCREASING military demands on the petroleum industry have brought into bold relief the crude-oil reserves now available to meet combined military and civilian demands, emphasizing the necessity for a greater efficiency in recovery from what has been discovered than ever before, particularly in light of the absence of new discoveries. This situation-and the fact that the industry, as well as members of the Government charged with governing oil production, desire to meet all crude-oil demands made of the industry with the least loss in tangible reserves through production practices-paves the way for increasing application of sound principles of production engineering and conservation.

Jan 1, 1944

By H. H. Stoek

THE fundamental reasons underlying the choice of a method of mining a coal seam are safety of operation, cheapness of producing the product and the character of the product as a saleable article. From the standpoint of safety, open or strip coal mining is always preferable, as many of the dangers inherent to underground work are absent, such as explosions of gas and dust, falls of roof and coal, and also to a great extent those due to haulage and the use of explosives, thus eliminating three of the chief causes of accident from which about 75 per cent. of the underground accidents in coal mines occur. The conditions under which coal is stripped also make the work much safer than ordinary quarry work, as the depth. of the pit is usually comparatively slight. From the standpoint of low mining cost, there is much misapprehension and many of the costs given are misleading in that they do not take into account such items as the destruction of the surface for future use, the full cost of the removal of the overburden, depreciation, amortization, coal depletion, loss of time through floods and from bad weather in winter, etc. Coal is no doubt often put on the cars at less cost by stripping than by underground mining, but by no means always so, as is too generally assumed. In some cases coal must be obtained by stripping or not at all, due to the small amount of overburden that renders underground mining impossible.

Jan 9, 1917

By Persifor Frazer

INTRODUCTION For various reasons I have not specified the locality where the research indicated in the following pages was undertaken. It will suffice to say that it was on the grounds of a villa once remote from, but now completely surrounded by, its neighboring city, and in close proximity to an industrial establishment of great extent and importance manufacturing many kinds of steel articles and employing upwards of thirty chimney-stacks for power and process work. The problem was to discover the cause or causes of the mortality to trees and plants on the place, and to trace these causes to their origin. Before undertaking this experimental work, the bibliography accompanying this paper was compiled and studied. It appears from an examination of the careful scientific work performed by the ablest French, German, and English chemists during the last 25 years that they are unanimous in assigning the principal-in fact, the overwhelmingly predominant-cause of the destruction of vegetation to sulphur oxides, resulting either from direct- oxidation of sulphur in oil of vitriol works, etc., or from the oxidation of the sulphur from the minerals associated with commercial coal. Schröder and Schertel showed in 1884 that the sulphates deposited upon the leaves are not injurious to the plants; and Freytag proved that free sulphuric acid could not be found

May 1, 1907

By J. Sharshall Grasty, Thomas L. Watson

The users of barite in the United States derive their supply partly from the domestic production and partly from the imports from foreign countries. According to the Mineral Resource division of the U. S. Geological Survey, the domestic production of barite in 1913 was 45,298 short tons, valued at $156,275, or $3.45 a ton, and the imports of crude barite were 35,840 short tons, valued at $61,409, or $1.71 a ton. These figures clearly show a decided advantage in cost of the foreign over the domestic barite to users in the United States. The difference in cost is the only advantage to the consumer of foreign barite, for there are large reserves of the mineral in the United States of good grade. The production of many of the operating mines is capable of decided increase, and it is believed that the operating mines together with the large reserves of undeveloped deposits of barite are entirely adequate to meet the demands of the users in the United States. Deposits of barite are known in California, Idaho, Nevada, and Alaska, but most of them are undeveloped because there is, apparently, no market for the material in that region. The domestic production is derived from Missouri .and the Appalachian States, the greater part being obtained from Missouri. Following the outbreak of war in Europe many users of foreign barite in the United States have been forced to seek their supplies at home. It seems opportune at this time, therefore, that a general review be given of the barite industry in the Appalachian States, one of the two areas from which the domestic supply of the mineral is derived, and that attention be directed to the undeveloped deposits in the region. Briefly, then, this paper reviews the barite industry in the Appalachian States, and describes the occurrence, preparation, and uses of the mineral. General Character Barite, known commercially as barytes or heavy spar, is barium sulphate (Baso4), containing when pure BaO, 65.7 per cent., and S03, 34.3 per cent. The specific gravity is 4.3 to 4.6, and the hardness 2.5

Jan 1, 1915

By J. M. Hassler

Nowhere can there be found a more misleading statement than the old one that "Iron can be manufactured cheaper in the South." During the past decade ironmakers and users of iron have heard varied and sundry stories of the wonderful resources of the Birmingham district, including abundant ore and coal fields, cheap labor, a wonderful climate and similar industrial Utopian statements. Birmingham represents the major portion of the iron business in the South, and as Birmingham fares so goes the iron business of the South. The intent of this paper is to shed some light on the actual conditions surrounding ironmaking in the South, especially in the Birmingham, or North Alabama, district. By a presentation of facts it is desired to point out that the "cheap iron" of the industrial South is a thing of the past, primarily because of increased labor cost and because labor is radically different in performance to what it was years ago. Also, because most of the raw materials needed in ironmaking that would be classed better than inferior are gone. Important Factors The several important factors that have been responsible for this change are : 1. Shrinkage of the iron business in the South. 2. Increased labor cost. 3. The development of the South, with an industrial trend, without a substantial increase of its own iron-consuming market. 4. Increased freight rates, which has narrowed the market that might be reached from this district. 5. Depletion of the better grades of raw materials, both ore and coal. Shrinkage of Iron Business in South.—Table 1 was prepared in early 1936 and revised in 1937, of blast-furnace units in the North Alabama district, considering the year 1936 compared with a maximum number of furnace units of previous years, the peak point being very near the year

Jan 1, 1937