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By Fieldner. A. C.

"In preparing this paper, an attempt was made to obtain results of plant-scale carbonization tests on washed and unwashed coal tram to same mine. A letter. in which the following questions were asked, was sent to some 50 coke-oven superintendents and others who might be interested:“What is the influence of washing coal on:(1) The chemical and physical properties of coke, as for example, the size, the amount of breeze, the fracture, strength, cell-structure, etc.(2) The quantity and quality of gas and by-products.(3) The capacity of the ovens.(4) The composition of the coal..""Your general opinion, as well as any specific data or results of testa, on this important subject will be greatly appreciated.""Of the 45 replies received, 24 stated that they had never used washed coal; 11 had used washed coal but had no comparative data on similar coals washed and unwashed; 7 answered some of the questions based on their general experience; and 3 gave some test data on Pittsburgh bed coal from western Pennsylvania. In none of the three tests did the washed coal come from the same mine as the unwashed. The washed coals in the three tests were from the same washery - one of modern construction in which the operations are under careful technical control in order to give a uniform product containing a minimum of surface moisture. The unwashed coals which were previously used in these plants were from different nearby mines in the same coal bed, and were supplied by the same company. Obviously, no sweeping or finale conclusions can be drawn from these few tests on coal from a single washery. Therefore, the writer vas obliged to consult the literature, coal-carbonization and coal-washing engineers, and other authorities to supplement the fragmentary information gleaned from the questionnaires in order to present a picture of chat gas engineers may expect from the use of washed coal in a carbonizing plant."

May 1, 1930

By Clifford H. Summers

This report describes an experimental program which we conducted on behalf of the U. S. Bureau of Mines, to select from currently available materials two novel systems of construction for air-restraining bulkheads to be used in control of radon-polluted air in underground uranium mines. The program included both laboratory and field tests, the latter conducted in a portion of an operating mine owned and operated by Union Carbide Corporation at LaSal, Utah. The test site was a worked-out, double entry stope having a Volume of about 2000 cubic meters, and was located immediately adjacent to an exhaust airway. The bulkheads were constructed of 15 cm x 1.5 cm timber uprights, 5 cm x 15 cm horizontal members supporting a close-fitted 13 mm plywood curtain-wall., which was covered with a low-permeability membrane to seal in the radon-polluted air. The two membrane materials selected for testing were chosen from a list of twenty-two potentially acceptable candidates using criteria such as strength, flammability, ease of application, adhesion, radon permeability, and elasticity. Thirteen of the candidates were tested in our laboratories for adhesion to plywood and to both wet and dry concrete (simulating wet and dry mine rock surfaces), and for their general physical properties, including radon permeability. The final selections made by the Technical Project Officer, and based on our recommendation, were a pre-formed ethylene propylene diene monomeric rubber (EPDM) membrane 1.12 mm thick, normally used as a roof sealant in industrial construction, and available from Carlisle Tire and Rubber Co., Division of Carlisle Corp., Carlisle, PA, and Aquafas 48-00, a water-based mastic used in a wide variety of commercial applications and available from H. B. Fuller Co., Foster Products Division, Spring House, PA. The EPDM membrane was applied as a single sheet, laminated (dry) between two layers of plywood, and the Aquafas was applied both by troweling and spraying onto a plywood surface. In the field test, radon concentrations were continuously measured before, after, and in the trapped air behind each bulkhead. Temperature, pressure, and velocity of the air in the adjacent airway were also measured and recorded continuously. Radon fluxes at the rock/air interface and through the bulkheads themselves were measured manually on a frequent basis. All continuously acquired raw data were recorded automatically on two USBM Data Aquisition Systems (DAS), and the raw data were converted into engineering units and recorded on magnetic disks by a specially programmed microcomputer that was interfaced with the DAS's. Relatively clean (i.e. low radon concentration) air was pumped into a point near the face of one test bulkhead from a location 170 meters away through vent bag. Several air curtains and two air-restraining bulkheads were erected in passageways adjacent to the test area in an effort to control both velocity and radon concentration of the air flowing past the bulkhead faces. An average concentration of approximately 500 pCi/liter at a flow of 550 m3/minute was attained as the background concentration against which leakage through the bulkheads was measured. The entire field test period extended from October, 1981 to March, 1982, a total of six months, and was subdivided into seven successive time periods: 1) site preparation 2) background measurements prior to bulkhead construction 3) passive restraint, with bulkheads in place and totally sealed 4) open bleeder period of natural convection ventilation in and out of the bulkheaded area through a 10 cm (diameter) opening, with connecting tubing; leading into an Exhaust airway 5) open bleeder period, having forced exhaust through a 1.0 cm opening using a servo-controlled fan 6) charcoal trapping period, using the servo-controlled fan to exhaust air through the charcoal traps, to test the effectiveness of such traps in removal of radon from the exhausted air 7) site decommissioning Each of the two systems tested, one incorporating the pro-formed EPDM-rubber membrane and the other utilizing Aquafas 48-00, was assessed for effectiveness in controlling radon-polluted air by observing the change in the radon concentration in the ventilation air flowing continuously over the surface of each bulkhead. The sensitivity of the observed measurements was limited by the volume flow-rate of the ventilation air and the radon concentration in that air. The data would indicate that the observed increments in radon concentration in the ventilation air moving across bulkheads B-l and B-2 were essentially zero within the limits of sensitivity of the measurements. Data from radon flux measurement taken both on the sealed ribs adjacent to the bulkheads and on the bulkheads themselves did not differ significantly from blank data.

Jan 1, 1982

By D. L. Forrester

This paper, describing the milling practice of the Old Dominion Co., is one of a series being prepared by the: United Staten Bureau of Mines. ACKNOWLEDGMENT In the preparation f this paper, acknowledgment is made of the valuable service rendered by R. S. Allen, metallurgist of the Old Dominion Co. T. G. Chapman, one f the consulting engineers of the Bureau of Mines, assisted in arranging the paper for publication.

Jan 1, 1931

Rock property tests were performed on NX-size diamond drill core from the roof, floor, and coal from the longwall mining section of Federal No. 2 mine, West Virginia. The purpose of these tests was to determine the engineering properties of the various strata as part of a ground control study of the longwall operation. The following tests were performed: 1. Uniaxial compressive strength, Young's modulus, and Poisson's ratio 2. Triaxial compressive strength 3. Brazilian tensile strength 4. Modulus of rupture 5. Specific gravity Thirteen boxes of core delivered to the University on April 1, 1974 were identified as follows: 2 PTR 1 -2 boxes of roof rock 2 PTF 1 -2 boxes of floor rock 2 PTR 2 -2 boxes of roof rock 2 PTF 2 -2 boxes of floor rock with approximately 3 ft of coal in Box 2 (designated 2 PTC 2) 2 PTR 3 -2 boxes of roof rock 2 PTF 3 -2 boxes of floor rock 1 PC 5 -1 box of coal

Jan 1, 1976

By S. S. Venkata

This volume describes a comprehensive program of research into the reliability of mine electrical power system components and the resultant reliability of the total system. The research effort encompassed analytical models, laboratory testing and field testing. The analytical work included definition of terms, fail rate functions and distributions, failure rate estimation and techniques and procedures for theoretical reliability assessment. One of the primary mine power system components addressed in the study was the ac molded case circuit breaker. This device is known to have low reliability and hence an unfavorable impact on mine safety and productivity. Ac molded case circuit breaker reliability was studied by analytical means, laboratory testing and field monitoring. A similar three-pronged' effort was made to study the reliability of undervoltage relays/releases. Particular emphasis was placed on new solid state undervoltage relays. The reliability of bulk power components, such as trailing cab les, motors, control gear, and other equipment, was assessed by gathering maintenance records from active mines. These data were compared to similar records from other industries. The work was extended to include the reliability, availability, maintainability and safety of these components.

Jan 1, 1979

By George Watkin Evans

The United States Geological Survey has estimated 1 that the State of Washington contains 11,412,000,000 tons of bituminous coal and 52,442,000,000 tons of subbituminous coal, in beds more than 14 inches thick. As the present rate of production is about 4,000,000 tons a year, Washington apparently contains coal enough to supply Pacific coast markets for many years. The character of the coal beds of Washington renders the production of clean coal very difficult, and a considerable proportion of the output is washed before it is marketed. In 1915 Washington ranked fifth among the States in the amount of coal washed, though only twentieth in total output. In that year 37.9 per cent of the coal produced in the State was treated in surface cleaning plants. On account of extensive folding and faulting of the coal measures, mining in Washington presents many difficulties; therefore a description of the methods employed at some of the mines may be useful in planning operations in other regions, and is presented in this bulletin. The coals of Washington differ in quality, ranging from true lignites in Cowlitz County in the southern part of the State to anthracites in the Mount Baker district of Whatcom County, in the north~ rn part. Most of the output consists of subbituminous and bituminous coals, the latter including both coking and noncoking varieties. Analyses of the coals of the State and descriptions of the beds from which the samples were taken have been printed in publications of the United States Bureau of Mines.2 Details of coal beds and analyses of the coals of King, Kittitas, and Pierce Counties have also been published by the Washington Geological Survey; 3 and most of the coal beds of the State are described in some detail in a bulletin of the United States Geological Survey.4 In 1918 mining was in progress at 72 mines in the State 4a; 46 of these mines each employed more than 10 men underground. These mines were distributed as follows: Thurston County, 1; Lewis County, 7; Kittitas County, 14; King County, 16; Pierce County, 6; Skagit County, 1; and Whatcom County, 1. During that year a total of 5,847 men were employed, 4,172 underground and 1,675 on the surface. The average number of days worked in the State was 275, and the average yearly output per man was 706 tons. Coke is made only in Pierce County by four companies, which have a total of 341 beehive ovens. In 1918 they produced 93,699 tons of coke. Up to 1919 mining machines were little used in the State. In 1917 only 6.61 per cent of the coal :produced was undercut by machines. In that year 58.95 per cent of the coal was mined by hand, and 34.44 per cent was shot off the solid. The explosives used were as follows: Black powder, 36.6 per cent; dynamite, 38.l per cent; and permissible, 25.3 per cent. The State of Washington is divided naturally into two parts by the Cascade Mountains which extend north and south somewhat west of the middle of the State. The coal areas east of the range will hereafter be referred to as eastern Washington-though nearly all of it is west of the middle of the State-and that on the west side as western Washington. The geographical distribution of the coal fields is shown in Plate I. Exploration of the State has not been exhaustive enough to preclude the possibility of discovering, besides the foregoing, other districts that contain deposits of coal in commercial quantities.

Jan 1, 1924

By Thomas Fraser

WHEN the Bureau of Mines initiated the program of large-scale research and development in the field of synthetic liquid fuels authorized in the Synthetic Liquid Fuels Act of April 5, 1044, the Coal Preparation Section was assigned the task of obtaining data on the preparation characteristics of the coal in large reserves that might be adaptable to use in this new industry. It is natural that, as the rapidly developing general research program brought about new concepts of raw-material quality, preferred geographical location, and the like, the orientation of coal-preparation investigations should have undergone some change. The first major assignment was the sampling and testing of a series of typical American coals deemed to he suitable for hydrogenation based on early research work conducted by the Bureau of Mines. This first series of tests has been completed and is reported in this paper.

Jan 1, 1950

By Thomas P. Dolley

Building stone, cassiterite, kaolin, gold, lime, and peat were the only commodities mined, The country's main economy was in agriculture, primarily in coffee exports. Tribal violence occurred again, between the Hutu and Tutsi tribes, causing an estimated 50,000 deaths, mainly in rural and mining areas. The inflation and a large deficit continued. The country continued to import cement, fertilizers, oil, and petroleum products. Burundi possessed numerous small gold deposits. The northwest and north-east were the country's two most important gold-bearing regions. A large kaolin deposit was found at Ngozi, and its mining was specified in the fifth 5-year development plan for 1988-1992. In the area of Rugombo, limestone was being explored with the intention of opening a cement plant.

Jan 1, 1990

The U.S. Bureau of Mines (USBM) was established in the public interest to conclude inquiries and scientific and technologic investigations on mining and the preparation, treatment, and utilization of mineral substances; to promote health and safety in the mineral industries; to conserve material resources and prevent their waste; to further economic development; to increaseee efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting those industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the U.S. Bureau of Mines to "disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act." In accordance with this directive, USBM reports the findings of its research and investigations in its own series of publications and also in articles that appear in scientific, technical, and trade journals; in proceedings of conventions and seminars; in reference books; and in other non-USBM publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make this kind of list both necessary and valuable. This edition describes reports and articles published during calendar years 1992 and 1993. It supplements the 50-year list of Bureau publications from July 1, 1910, to January 1, 19602; and these 5-year lists of publications and articles: from January 1, 1965, to December 31, 1969\ from January 1, 1970, to December 31,19745, from January 1, 1975, to December 31, 19796, from January 1, 1980, to December 31,19847, and from January 1, 1985, to December 31, 19898?.

Jan 1, 2007

By Carroll W. DeKock

Thermodynamic data for selected metal sulfates were critically evaluated and compiled as part of the Bureau of Mines program to provide a scientific base for use in developing new technology and predicting the feasibility of new processes. Values for Cp°, S°, H° - H°298, - (G° - H°298)/T, ?RC, ?Gf°, and log Kf as functions of temperature are given in tabular form. Thermodynamic data were compiled for Ag2SO4, A12(504)3, A12(S04)3?6H20, BaSO4, BeSO4, BeSO4?2H2O, BeSO4?4H20, CaSO4, CaSO4?1/2H20, CaSO4?2H2O, CdSO4, CdSO4?H20, CdS04?8/3H20, 2CdO?CdSO4, Cs2SO4, In2(S04)3, K2504, KA1(S04)2, KA1(S04)2?12H20, Li2SO4, L12SO4?H20, MgSO4, MgSO4?H2O, MgSO4?2H20, MgS04?4H20, MgS04?6H2O, MgS04?7H2O, Na2SO4, Na2S04?7H20, Na2SO4?10H20, (NH4)2SO4, NH4A1(S04)2, NH4A1(S04)2?12H20, PbSO4, Rb2SO4, T12SO4, and Zr(S04)2.

Jan 1, 1986

By R. S. Olsen

The Bureau of Mines is engaged in research to recover aluminum from kaolinitic clay and other nonbauxitic domestic resources. As part of this work, calcined Georgia kaolin was prepared by a process that prevents slime formation and makes the leached residues fast settling and easy to filter. The leaching reaction for calcined kaolinitic clay in a 5 pct stoichiometric excess of boiling 23-to 26-pct HCI was found to be zero order. Rate constants based on the weight-fraction of aluminum in the clay were found to be between 0.095 and 0.15 min-1 depending on feed preparation and leaching parameters. The mathematical relationships between aluminum extraction and time for both batch and continuous, stirred-tank operations were derived and verified experimentally.

Jan 1, 1983

By J. W. Thompson

A mining company for a period of 12 years bad been selling its ore to a certain smelting company for the purpose of obtaining a continuous and steady market for its ore and for the purpose on the part of the smelting company of obtaining a continuous and steady supply of ore for smelting; an agreement was entered into by which the mining company agreed to eell and the smelting company agreed to purcshase at ruling prices all the ore produced by the mining company of certain' stated grades, and to this end the mining company agreed to actively operate its mines. It is no longer the rule that a suit will not lie for the specific performance of a contract relating to personal property ; but the question for determination in such a case is whether the complainant has a plain, speedy and adequate and complete remedy at law, and if he has no such remedy, specific performance will be granted. In an action by a smelting company for the specific performance of a contract of sale it appeared that the ore produced by the mining company bad a peculiar value for smelt. i.ng purposes and was not readily obtainable elsewhere, and it would be practically impossible to measure the value for determining the loss the complainant would sustain· if the smelting company were not ,able ,to obtain the ore under the contract. It is comparatively simple for a court of equity to enforce the agreement as it pertains to the normal product of the mine and there is no plausible reason why a court may not require a performance on the part of the mining company where the mining company obligated it:Belf to operate all its mines. There is no delicate or complex condition involved in the production or delivery of the ore 'or in obtaining_ the stipulated prices agreed upon, and there is nothing apparent that will necessitate supervisory· control in requiring performance on the part of the mining company. A decree for specific perfoi:m,ance would require no supervision by the court either for the operation of the mines or for ascertaining and fixing the prices the mining company is to receive for its ore.

Jan 1, 1919

By T. H. Miller

An attempt has been mace in this publication to present annotated references to all articles pertaining, to ore dressing that were published during 1931 and 1932; in a few instances reference is made to articles published prior to 1931 where the articles have not been included in previous bibliography appended to the annual statistical discussions of ore concentration published by the Bureau of Mines. Articles have been taken from more than 75 periodicals, journals, serials, etc., and 423 articles are abstracted herewith. A number of these abstracts, particularly those appearing in foreign publications, have been taken from Chemical Abstracts (published by the American Chemical Society, Easton, Pa.), the general use of which the authors wish to acknowledge. Other annotations were taken directly from the original publications. The entire field of ore dressing has been included in the bibliography and articles dealing with crushing, grinding classification, concentration, thickening, and filtration have been included, as well as on amalgamation, cyanidation, leaching, magnetic concentration, washing, etc., and on theory and laboratory operation. The articles are arranged in alphabetical order by authors. Lack of printing funds prohibited the inclusion of a subject index.

Jan 1, 1934

By Frank L. Hess

"New England" and "granite" if not synonymous are at least associated terms. Where there are granites that are not deeply eroded there are usually pegmatites, the most erratic of rocks, and of them New England has a full portion. Many of the New England pegmatites contain the rare alkalis - lithium, rubidium, and cesium. however, the same in homogeneity of the earth's crust that has made the New England pegmatites unusual, in that so many of them contain the rare alkalis, has likewise made the distribution of the rare-alkali minerals sporadic even in those pegmatites, and most contain only enough to furnish collectors with more or less ornamental and uncommon minerals. New England has long had numberless collectors of minerals, and the mineralogists of its various schools have published many papers on the pegmatitic minerals, including those of the rare alkalis, but none of the papers have dealt with estimates of quantities. In this paper we have tried to place the emphasis on quantity rather than on mineralogy.

Jan 1, 1943

By J. R. Thoenen, Hugh D. Pallister

"INTRODUCTION The Stone Hill Copper project resulted from the recommendations made in the war minerals report on this deposit by engineers of the Bureau of Mines 4/ and a similar report of the Geological Survey. 5/ACKNOWLEDGMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of domestic mineral resources to the end that they make the greatest possible contribution to the national security and economy. The Mining Division, Lowell E. Moon, chief, conducts preliminary examinations, does the actual investi¬gative work, and prepares the final report. The Metallurgical Division, Oliver C. Ralston, chief, analyzes samples and makes beneficiation tests.This report was prepared under the supervision of Paul M. Tyler, former regional engineer, Eastern Region, and is based on the examination and investigation of the deposit by Hugh D. Pallister, mining engineer, made under the immediate supervision of Richard W. Smith, former District Engineer for Alabama and Mississippi.The report was rewritten and prepared for publication by J. R. Thoenen, chief, Tuscaloosa Branch, Mining Division.LOCATION AND ACCESSIBILITYThe Store Hill copper mine is about• 12 miles south of Heflin, the oounty seat of Cleburne County, Ala. Heflin, a town with a population of approximately 1,700, is the nearest shipping point for freight and express. It is on the Southern Railway, between Birmingham and Atlanta. A rural mail route passes within quarter of a mile of the mine. Paved reads from Heflin lead to Atlanta, Birmingham, and Montgomery. The country Toads leading from Heflin are well-maintained but are practically inaccessible during inclement weather. The road crossing the property within a hundred yards of the mine needs grading and repairing (see fig. 1)."

Apr 1, 1948

In 1967 the United States consumed 58.8 quadrillion Btu of energy. Both the Atomic Energy Commission and the Resources for the Future, Inc., a private economic forecasting group, predict that the United States energy requirements will reach 135 quadrillion Btu by the year 2000. In 1967 bituminous coal produced 21.4 percent of the energy used in the United States and anthracite coal another 0. 5 percent. Coal Reserves Coal reserves make up about four-fifths of the United States storehouse of fuel in proven reserves. Seventy-five percent of all fuel, likely to be found and recovered is coal. Electric utilities consume more than half of the bituminous coal mined in the United States in generating 53 percent of the nation's electricity. Atomic Energy Commission analysts have proposed the development of a vast "national energy system" based upon long-distance electrical transmission from abundant untapped coal reserves in the western United States. The study predicts that even if uranium supplies are available and economic breeder reactors developed, coal requirements for electricity generation will more than double by 1980 and increase another 50 percent before the year 2000.

Jan 1, 1970

By Charles J. Haas

The objective of this research was to investigate the interaction phenomena of rock and types of rock bolts to develop design principals for using grouted roof bolts. The investigation was to determine the effectiveness of grouted bolts in resisting lateral displacement and axial separation along fracture planes, and also to determine if grouted bolts eliminate the axial tensile stress near the anchor and the resulting rock fracture. The first year's effort involved defining the post-tensioning response of grouted bars and determining the amount of shear resistance generated by conventional and resin-grouted bolts. A finite-element analysis showed that if the rock and resin grout behave in an elastic manner, the post tensioning of a grouted bar will affect mine roof stability only if movement occurs near the collar. An experimental shear test program revealed that both conventional bolts and resin-grouted reinforcing bars significantly increase shear resistance along fracture or bedding plane when the average normal compressive stress on that plane is low (in the order of 25 psi) and when the bolt is oriented so that the shear displacement tends to lengthen the bolt. An increase in shear resistance is also noted at the higher normal pressure of 250 psi; however, the increase is small compared to the corresponding shear resistance without a bolt. Conventional bolts oriented so that they tended to loosen with shear displacement added no significant shear resistance.

Jan 1, 1974

By H. W. Brandt

A field test was designed to inject a specially formulated two compound epoxy resin into the roof rock ahead of a working face to cement fractures and formation interfaces at the Westmoreland Coal Co., Winding Gulf Div., Eccles No. 5 Mine, Eccles, West Virginia. Five 30 foot long X 2 inch diameter, hold were drilled at an angle of 15° above the plane of roof line front the face of a working entry. The epoxy resin compounds were pumped through a proportioning unit and mixed in-line before being discharged into the drill hole under treatment it injection pressures up to a maximum of 450 psig. When the coal face was advanced an anomalous failure of the roof rock occurred in the treated section. Further testing was suspended until the cause of the failure could he determined. The polymers were tested, under confined conditions, in 2 inch pipe columns. Extreme temperature and pressure (up to 2400 psig) rises were recorded as they cured, It was concluded that this pressure source fractured the rock and caused the roof failure. The entire program was terminated after it was determined that the heat rise and resultant high pressures could not he controlled chemically or mechanically.

Jan 1, 1978

By L. C. IlsLey

[In 1922 a conference of representative coal-mine operators, cable manufacturers, mining-machine manufacturers, and representatives of the United States Bur eau of Mines vas held at the Pittsburgh Experiment Station, regarding suitable cables for use with permissible raining machines. This conference recommended that the Bureau investigate rubber-sheathed trailing cables in order to obtain specifications for tests leading to approval for rise with mining machines. Effective until such time as an investigation could be made, the bureau asked the several manufacturers of approved mining machines to recommend cables for wise with their machines. In general the Cables recommended tentatively approved. Arrangements for the tests were completed in 1927. Concentric-type cables were investigated first, and Reports of Investigations, Serial No. 2909, covering the tests, was issued in January, 1929.]

Jan 1, 1929

By J. Wade Watkins, Joseph W. Horne, Arthur Matzick

"A successful procedure for the recovery of a valuable product from weathered tank-bottom settlings has been developed in the laboratories of the Bureau of lines and used in a field pilot plant. These heavy emulsion settlings, generally regarded by the industry as waste material, have usually been drained into open pits or storage ponds and eventually destroyed.Laboratory examination of the waste material shows it to consist essentially of a ""water-in-oil"" emulsion containing a considerable volume of congealed ""paraffin."" This paraffin is mainly high-melting-point wax; known in the industry as microcrystalline wax, for which there is an increasing demand.Because of the physical properties of this wax, the tank-bottom settlings are not responsive to conventional methods used for demulsifying ordinary crude-oil emulsions.The work upon which this report is based was conducted by the Bureau of Mines in cooperation with -the Kansas State. Board of Health and with special cooperative agreements-with the Cities Service Oil Co, Bartlesville, Okla., and the Bareco Oil Co,. Barnsdall, Okla. The studies were made under the general supervision of R. A. Cattell, chief engineer, Petroleum and Natural-Gas Division, Bureau of Mines, Washington; D. C., and H. C. Fowler, supervising engineer, Petroleum Experiment Station, Bureau of Mines, Bartlesville, Okla., and under the direct supervision of Ludwig Schmidt, senior petroleum engineer, Bureau of Mines, Bartlesville, Okla.Gratefully acknowledged are the assistance and cooperation given by the Cities Service Oil Co. of Oklahoma and especially by M. J. Kirwan, manager of production, and by Q. E. Beecher, general superintendent of production, Bartlesville, Okla., and to members of their staff at Oil Hill, Kans.The assistance and suggestions of V. R. Oakley, general superintendent, E. R. Wiles, director of research, L. G. Willis, field engineer in charge crude-oil supply, and Gerald DeWalt, chief chemist, and his staff of the Bareco Oil Co., Barnsdall, Okla., were of much value in the laboratory and recovery work."

Mar 1, 1946