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By Thomas M. Drown

At the meeting of the Istitote in New York, in February, 1880," I described a process of determining sulphur iu metallic allphides, with especial reference to the determination of pyrites in coal. The procem, as then described, is as follows: A solution of sodium hydrate, of 1.25 specific gravity, is saturated with bromine. If an excess of bromiue is used it must be neutralized by the addition of a little more sodium hydrate. The pulverized mineral or coal is moistened with 25 c.e. of this solution autl heated, then hydrochloric acid is added cautiously to just acid reaction. This operation is repeated with another 25 c.c. of the alkaline solution, and again rendered acid. The mixture should be kept hot. The contents of the beaker or dish are then

Jan 1, 1881

By Jules E. Jenkins

In the past quarter century the seismograph has I played an increasingly important role in evaluating vibratory effects transmitted to adjacent communities by industrial blasting operations. In this period research has advanced through two major phases-from falling pin seismometers to three- component recording seismographs. The initial phase of this research is now regarded as the era of recording, during which the seismograph merely recorded occasional events. It has emerged from this stage into the era of control and analysis and in this later period has been recognized as a full-fledged industrial tool. Although the falling pin machines of earlier years indicated probable amplitudes of industrial blasting vibrations, they gave no reliable measure of such displacements, nor did they provide essential information concerning direction or frequency of motion.

May 1, 1956

By R. E. Bish

IN an effort to distinguish experimentally between the radically different limits of two-liquid im-miscibility reported for the Cu-Pb system by Borne-inann and Wagenmann and by Briesemeister (see Fig. I), it was found that the high temperature homogeneous liquid containing between 41 and 93 pct Pb could not be frozen without separation into two liquids with the fastest cooling technique that could be devised. Thus, the two-phase state could not be distinguished with certainty from the one-phase state by the examination of quenched samples. To overcome this obstacle the following method for detecting the presence of an interface between two immiscible conducting liquids at temperature was developed. Measurements made by the new method substantiate the Briesemeister diagram in its general form. The method consists essentially in the measure-

Jan 1, 1953

By John F. Abel

At the spring meeting of the Open Pit Division of AIME's Arizona Section, I was asked a question which indicates the acceleration of technical advancement. The question was: "How does an engineer at a properly keep abreast of what is new?" The fact that some 200 Arizona AIME members were at the meeting is a testimonial to the desire of these men to do just that- keep abreast. There is a great deal of talk in academic circles about the built-in obsolescence of an engineering or scientific education, too. About 100 commencement speakers every spring are sure to admonish the graduates that education is a continuing thing. Mining engineers are a small fraternity. We keep informed by talking to one another. Talking shop is valuable but there is no substitute for reading.

Jan 1, 1970

?Aaronson, Alfred E , Oil Producer, Pres, Tuloma Oil Co Tulsa, Okla '18 ||Abad, Leopoldo F , College of Mm , Univ of California Berkeley, Cal '23 ||Abadilla, Quirico A , Geol Dept, Cia Mexicana de Petroleo "El Agmla," S A , Edifico "El Aguila," Esq, Caller Aurora y Comercio, Tampico, Tamps , Mexico '20 ||Abbey, Robert Graham, Student, Case School of Applied Science Cleveland, O '21 Abbott, Clarence E, Gen'l Supt, Iron Mines Div, Tenn Coal, Iron & R R Co, 1405 Minnesota Ave , Bessemer, Ala '04 Abbott, Louis Benjamin, Chief Engr , Consolidation Coal Co , Elkhorn Div Jenkins, Ky '15 Abbott, Robert R , Met Engr , Peerless Motor Car Co Cleveland, Ohio '12 ||Abbott, Wells Osborn, Student, Univ of Arizona Tucson, Ariz '23 Abe, Asaka Ashiya, Mukogun, Hmyogoken, Japan '14 Abeel, George H, Jr , Cons Min Engr 4612 W 17th St , Los Angeles, Cal '18 Abel, Albert E , Asst to Pres , Valley Mould & Iron Corpn Sharpsville, Pa '19 ?Abeloff, Miran S 322 W 45th St, Ness York, N Y '21

Jan 1, 1923

By Abderrafih Guessous

INTRODUCTION Morocco is an important lead-zinc producing country: 120,000 tons of lead concentrates were produced in 1968. Zinc ore production is less, 67,000 tons of concentrates in 1968. Most of the present production comes from three districts (fig.1) (i) Touissit-Bou Beker district, in the eastern part of the country, close to the border with Algeria. (ii) Aouli-Mibladen district, in the central part of the country. (iii) Aouam district, about $0 miles south of Meknes. In the first district lead and zinc are always found together. The two other districts produce mainly lead. This paper will be limited to a short description of geology and mining methods in the three aforementioned districts. More detailed geological informations can be found in the symposium on lead-zinc deposits in Africa (1).

Jan 1, 1970

By S. H. Ash

More than 100 minerals are mined and processed in the U. S. Management and labor have negotiated wage-scale agreements that have balanced wages and affected cost of labor in such a manner that comparisons can be made of transportation costs. Transportation of materials underground has become of vital importance. This report describes underground haulage methods and equipment, presents cost analyses, and discusses future plans for underground transportation in metal mines. It does not cover hoisting in shafts or slopes by cage, skip, or cars. Advancements have been made by the metal mining industry in lowering transportation costs in several mines, making it possible to mine orebodies or portions of orebodies not considered economically recoverable a few years ago. Numerous reports have been written on transportation at metal mines; this report covers recent haulage at some representative mines throughout the U.S. The term metal mine is used to include all noncoal mines from which up-to-date information was obtainable.

Sep 1, 1956

By Parke A. Hodges

CHROMIUM, one of the most vital of the strategic metals, has constantly increasing importance as research expands potential uses in alloy steel metallurgy. All signs point to a steadily growing use for chrome ore, and the general subject has received a great deal of attention recently.1 A relatively little known country, Southern Rhodesia produced a total of 5.949 million tons, or 18.6 pct of the total world chrome output, between 1906 and 1950, according to figures from the U. S. Dept. of Commerce. According to U. S. Bureau of Mines figures, Southern Rhodesia produced 291,525 tons in 1950 and 300,267 tons in 1951, or approximately 13 and 11 pct, respectively, of world production for the two years. In 1953 the Rhodesian Vanadium Corp. produced about 85,000 tons of which probably 7,000 tons were concentrate. Production by other companies was high. Large in themselves, the figures assume even greater significance because most of this output is of metallurgical grade.

Jan 8, 1954

West Virginia Geological Survey Morgantown, W. Va James D. Sisler, State Geologist. Of great importance among the publications of this Survey have been the volumes of Detailed Reports on the counties of the state These volumes take up in detail the geology, topography, soils and resources of the areas under consideration; they are profusely illustrated and each carries topographic and geologic maps Detailed Reports are available for areas as follows: Marshall, Wetzel and Tyler counties (1911) $3, Wirt, Roane and Calhoun counties (1911), $2 50, Jackson, Mason and Putnam counties (1911), $2, Cabell, Wayne and Lincoln counties (1912), $2 50, Doddridge and Harrison counties (1912), $2 50, Monongaha, Marion and Taylor counties (1913), $2 50, Kanawha County (1914), $2 50; Preston County (1914), $2, Logan and Mmgo counties (1915),12 50, Boone County (1915), $2, Wyoming and McDowell counties (1915), $2 50, Lewis and Gilmer counties (1916), $2 50; Raleigh County, Summers west of New River, and the coal area of Mercer County (1916), $2 50, Jefferson, Berkely and Morgan counties (1916), $2 50, Braxton and Clay counties (1917), $2 50; Barber and Upshur counties, and western Randolph County (1918), $3; Fayette County (1919), $3 25;

Jan 1, 1933

By Akira Ishizu, Nobuo Matsui, Hideo Yamamoto, Tatsuya Nagahama

At Kamioka Mine of Mitsui Mining & Smelting Co., Ltd., Japan there are three mills, treating a total of 6400 t/d of lead-zinc Ore. In the lead-zinc bulk differential flotation at Shikama Mill the addition of reagents is automatically controlled by the feed rate, the lead and zinc content in feed, froth and tailing, the pH and the concentration of cyanide ion in the pulp. As the zinc thickener overflow at Shikama Mill contains CU(CN)3--, ZnS, CdS, CN-, xanthate and frother, all the ingredients in the over- flow other than CN are floated by using the Nagahm flotation machine, and the water containing only CN- is effectively recycled to the lead- zinc differential flotation circuit. In the lead-zinc straight differential flotation at Mozumi Mill, the overflow of tailing pond is recycled especially to the cleaning flotation circuit by decreasing the pulp density. Thus the integrated recycling of wastewater greatly reduces environmental problem and in addition, it generates sizeable profit.

Jan 1, 1977

By Maurus Seet

Mainland China, with one-fourth of the world's population and one-tenth of its coal production, can no longer be ignored as a considerable force on the world energy scene. In terms of annual productivity, China's 300 million tons of coal rank third behind the Soviet Union with 655 million and the United States 557 million (1968 Minerals Yearbook. USBM). When viewed from another angle, 1967 figures show that increased productivity from all coal-producing continents, with the exception of North America, was led by Chinese-dominated Asia with a 19% gain. Not unpredictably though, China, on a per capita basis, is closer to the bottom of the list among members of the industrial community. Despite its misspent youth, and despite the set- backs caused by the Big Leap Forward of the late 50's and the Cultural Revolution of the late 60'S, the People's Republic has managed to make some impressive strides in developing its coal industry over the past twenty years.

Jan 1, 1971

By Frank C. Appleyard

Southwest of the town of Saltville in western Virginia is Plasterco, a small village that has been a source of gypsum production since 1815. Boasting the deepest underground gypsum mine in the world, Plasterco has been the site of mining operations by United States Gypsum Co. for more than half a century. And although its own ore supply is dwindling, Plasterco's position as a source of gypsum and gypsum products has been ensured by the recent opening of the nearby Locust Cove mine, one of U.S. Gypsum's newest projects. In the early days, production of gypsum at Plasterco was very small, the primary use of the mineral limited to that of "land plaster"-ground gypsum spread on the land to sweeten the soil. Initial mining was confined to surface outcrops containing gypsum, but the construction of a local plaster-producing calcining plant in the late 1800's coupled with al- most total depletion of the surface rock spurred the start-up of underground operations.

Jan 3, 1965

The papers presented at the International Congress, held in San Francisco, Cal., Sept. 20 to 25, 1915, are published in 11 volumes of Transactions. In addition, an index volume is published, containing .besides the author and title index, a report of the business meetings of the Congress, and a brief digest of each paper presented. The following is a schedule of the volumes: Index and Digest.-General proceedings, indexes and digests. Vol. I. Panama Canal. II. Waterways and Irrigation. III. Municipal Engineering. IV. Railway Engineering. V. Materials of Engineering Construction. VI. Mechanical Engineering. VII. Electrical Engineering and Hydro-electric Power Development. VIII. Mining Engineering. IX. Metallurgy. X. Naval Architecture and Marine Engineering. XI. Miscellaneous. Aeronautics; Refrigeration; Agricultural Engineering; Engineering Education; Heating and Ventilation. Remember the New York Meeting, Feb. 14 to 17, 1916.

Jan 12, 1915

By Alan Lawley

AS part of a programme of experimental work on single crystals of rhenium and ruthenium, it was found necessary to have the crystallographic angles for these elements. The angles given in Table I were determined to the nearest minute of arc, by Univac Computer. The angle $ between (HKIL) and (hkil) is given by the formula: The angles given for rhenium should be particularly useful in view of the increasing interest in this element. For completeness, angular values are also given for cadmium zinc and magnesium; these form a more complete set of values than those given by Salkovitz.' The assistance of Professor J. Hobstetter and Mr. J. Crozier in the programming of this data is acknowledged. The work is sponsored by the Office of Naval Research under contract No. NONR 551 (19).

Jan 1, 1961

By W. F. McDermott

This is the dawning of the computer age in process control. As 1968 drew to a close, many plants had computer installations which were being used for logging, monitoring and reporting. Today, computer usage is given serious consideration before the construction of any major minerals processing plant. Unitized automatic control of individual processes is abundant. Many plants are considering closing these control loops, i.e., allowing the computer to direct the operation of the controllers (Digital Analog Control-DAC). The next step is to make the computer itself the controller (Direct Digital Control-DDC)1 Perhaps the most important future use of computers will be in controlling interrelated operations and control units. Progress along these lines depends on the steadily improving capabilities in the field of mathematical modeling.

Jan 1, 1970

By Klaus Schwerdtfeger

The rate of formation of silicon monoxide from silica spheres has been measured at 1500°C in H2, H2-H2O, H2-He, H2-Ar, and CO-CO2 gas mixtures. Indications are that in the hydrogen-containing gases the reaction rate is mainly determined by convective diffz~sion. In the CO-CO2 mixtures the rate approches a constant value which is independent of sphere diometer (and gas velocity). This suggests that a surface reaction becomes rate controlling in CO-CO2 gas. WHENEVER silica is exposed at elevated temperature to a strongly reducing atmosphere there occurs, inevitably, a volatilization of silica by the formation of gaseous silicon monoxide. Because of the importance of this reaction in metallurgical processes and laboratory experiments, its kinetics were studied in the present work. EXPERIMENTAL The spheres made of vitreous silica were suspended by a molybdenum wire in the hot zone of a gas-tight high-purity recrystallized alumina furnace tube of 3.1 cm internal diam and 100 cm length. Molybdenum wire resistance heating was used. A purified H2, H2-H2O, H2-He, H2-Ar, or CO-CO2 gas mixture was passed through the tube, from top to bottom. The amount of silicon monoxide formed was determined by weighing the silica balls before and after the experiments. The silica balls were made from commercially available translucent fused quartz glass. In experiments with hydrogen-containing gases the silica stayed vitreous during the experiment, whereas in experiments with CO-CO2 mixtures, which were performed over longer times, the balls were always crystallized to cristobalite (as determined by X-ray examination) at the surface. Constant-pressure head capillary flowmeters were used to control the composition of H2-He, H2-Ar, and CO-CO2 gas mixtures. The oxygen and water vapor were removed from the gases containing hydrogen by passage through columns containing platinized asbestos (450°C) and an-hydrone. The CO was purified from O2 and CO2 by passing it through activated copper (200°C) and through ascarite. The H2-H2O gas mixtures were prepared by passing purified Hz through a mixture of oxalic acid dihydrate and anhydrous oxalic acid held at a constant temperature in a water bath. The equilibrium water vapor pressures of oxalic acid dihydrate-anhydrous oxalic acid mixtures were taken from the available data.1 The furnace system was checked for sufficient gas tightness at regular intervals. As an additional check, the H2O and CO2 contents were measured in the exit gas and were found to agree closely with the metered contents when H2-H2O or CO-CO2 mixtures were used. When purified H2 was used, H2O pressures found in the exit gas were always below 0.1 mm Hg. These contents originate either from an incomplete reoxidation of silicon monoxide in the cold part of the furnace or from small leaks which cannot be avoided. If the latter is the case, such small uncontrolled H2O contents decrease the partial pressure of SiO in equilibrium with SiO2 by less than about 7 pct, which is considered small in comparison to other experimental uncertainties. The temperature of the furnace was controlled automatically in the usual manner. The reported temperature was measured with a Pl-Pt/l0pct Rh thermocouple and was accurate to ± 5°C. TRANSPORT-CONTROL LED RATE OF REDUCTION The gaseous convective diffusion from the surface of a sphere can be predicted from the semiempirical relationship obtained by Ranz and Marshall2 in a study of the evaporation of water and benzene drops in air. The following equation applies:

Jan 1, 1967

By Arthur Baker III

The orebodies are long bedding-plane lenses of chalcopyrite and sphalerite, associated with garnetite masses. Most of the orebodies are within a 50-ft thickness of Cambrian limestone; other Paleozoic limestones and dolomites are locally metamorphosed but only slightly mineralized. Pre-mineral faults are numerous, but shallow folds were the main ore-localizing structures. JOHNSON camp is in the northwestern part of Cochise County, Ariz., about 50 miles east of Tucson. The nearest major mining districts are Tombstone and Bisbee, respectively 27 and 50 miles to the south, and the Superior-Miami-Globe-Ray porphyry copper group, about 90 miles northwest. Like many mining camps of the Southwest, Johnson camp is said to have been worked by the Spaniards. The first production on record was in the early 1880's, when an unknown amount of oxidized copper-silver ore in the Peabody mine was mined from replacement orebodies in the Pennsyl-vanian Naco formation. From 1904 to 1911 outcropping oxidized ores in the Cambrian Abrigo formation were worked, and an estimated 100,000 tons of copper ore were shipped. In 1912 the first large sulphide orebody of the district, the Republic Manto orebody, was discovered, and in the following few years some 250,000 tons of predominantly sulphide ore were shipped. The average grade of this ore was approximately 4.5 pct Cu, 6 pct Zn, 0.8 oz. Ag, and 0.001 oz Au. The Republic, Copper Chief, and Mammoth mines were the principal producers during this period. Mining ceased in the district after 1920, and until 1943 only small-scale leasing operations were carried on. In 1943 all the mines that had been productive were acquired by the Coronado Copper and Zinc Co., the present operators, and in the 10 years since that time the district production has amounted to approximately 350,000 tons of milling ore averaging 2 pct Cu and 6 pct Zn. Most of this ore was produced from the Republic and Mammoth mines, but since 1950 a large part of the production has been from the new Moore mine. The total known production from the district, then, is about 3/4 million tons of copper and copper-zinc ore of low grade. All of this ore was produced from orebodies associated with garnetite in the middle member of the Cambrian Abrigo formation. In addition to this known production, an unknown tonnage of ore was extracted from the Peabody mine orebodies that lie in the Pennsylvanian Naco formation. Published information on the geology of the district is limited. Aside from brief references in various mining journals, only three papers on the district have been published.1-3 One of these is a U. S. Bureau of Mines report on a diamond drilling program, one is a brief paper on the general geology of the district, and the third is a report on geochemical experiments, with a section on the occurrence of the orebodies. The last two are by John Cooper, of the United States Geological Survey, who has done much detailed work in the area. Stratigraphy The rocks of the mineralized area are Paleozoic sediments ranging in age from Cambrian to Penn-sylvanian. Several disconformities are present in the stratigraphic column, the most important one being between the Cambrian Abrigo formation and the Devonian Martin formation. There are no angular unconformities. Within the district, the Paleozoic sediments lie in a fairly uniform monocline, striking northwest and dipping 30" to 50" northeast. This local monocline is part of a domal struc-ture centered in the Little Dragoon mountains to the southwest. The Texas Canyon stock, a quartz monzonite body intruded probably during the Laramide revolution, lies south of the mineralized area (Ref. 2, p. 33). The Paleozoic rocks dip away from the stock, and on the surface are separated from it by at least 1500 ft of Pre-Cambrian rocks. The outcrop pattern of the northeastern edge of the stock suggests that it may dip gently northeastward, passing below the mineralized area at moderate depth. No quartz monzonite has been found in mine workings or diamond drill holes, which reach to depths of 1000 ft. The only igneous rock found in the mineralized area is a lamprophyre dike cutting the Naco limestone in and near workings of the Peabody mine. With the exception of the lowermost beds—the Bolsa quartzite and the shaly lower member of the Abrigo formation—the Paleozoic sediments are predominantly carbonate rocks, Fig. 1. The middle member of the Abrigo formation, which contains the principal ore-bearing beds, is limestone, with thin shale partings throughout most of its 250-ft thick-ness. Near the top of this member is a sandy bed some 25 ft thick. The upper member of the Abrigo formation and the lower half of the overlying Devonian Martin formation are dolomitic, with num-

Jan 1, 1954

By Paul Averitt

In spite of recent trends in the United States toward construction of steam generating plants near mine mouths, and toward use of high-voltage direct current for long-distance transmission of electricity, coal in substantial amounts is being transported over relatively long distances to serve specific needs. As coal is a low-cost bulk commodity which is more suitable for use near the point of origin, some of these long hauls are of considerable interest because they show what can be done under the pressure for more and more coal to support industrial and economic growth. Japan has an Insatiable Appetite for Coal Perhaps the longest U.S. coal journey begins in the east Appalachian Basin of southern Pennsylvania, eastern West Virginia, and southwestern Virginia. High-quality coking coal mined in these areas is shipped by rail to Baltimore, Md., and to Hampton Roads, Va., where the coal is reloaded on freighters for shipment primarily to western Europe and Japan. In 1967, shipments of coal to western Europe totaled 19 million tons, and shipments to Japan totaled 12 million tons. Japan also imports coal from Australia, the U.S.S.R., Canada, Poland, the People's Republic of China, and to a lesser ex- tent from several other countries. In an effort to solve long-term needs, Japanese steel interests have contracted for the purchase from the Kaiser Steel Corp. of 51 million long tons of coking coal over the period 1970 to 1985. The coal will come from the Kaiser Steel Corp. mine near Fernie, British Columbia. This arrangement will reduce Japan's future dependence on Appalachian Basin coal.

Jan 10, 1969

By Thomas R. Smith

This paper covers oil shale resources in those countries that border the Pacific Rim. The major known resources around the Pacific Rim occur in the Western United States, Australia, the People's Republic of China, (PRC) and the Thailand/Burma region. The location of these deposits is shown in Figure 1. In 1965, the U.S. Geological Survey estimated world oil shale deposits of over 4 quadrillion tons having a potential oil yield of over 2 quadrillion barrels. If all this were extracted, it could meet the world's entire energy needs far into the future. However, the Survey also estimated the spent shale waste could cover all of the surface of the world to a depth of about 10 feet. Thus, for this and many other technical and economic reasons, it does not appear to be feasible to develop a large portion of the world's oil shale resources in this century; nor will shale in itself solve our energy problems. Nevertheless, shale oil and other ' synthetic fuels are expected to play an important role in new energy supplies in the longer term. WHAT IS OIL SHALE OR SHALE OIL? The term "oil shale" is sometimes a misnomer, in that the rock is often more of a limestone or siltstone than a shale. The common link between resources termed “oil shale" is that they all contain an insoluble substance cal led kerogen (which is from the Greek words for waxmaking). Kerogen is a form of organic carbon derived from a variety of plants ranging from algae to higher plants. When heated sufficiently, the kerogen generates hydrocarbons called shale oil, a form of synthetic crude oil that in most cases is lower in hydrogen content than conventional crude oil. The amount of oil in oil shale is relatively small --roughly 10 percent (by weight) in the richer shales. To upgrade this synthetic oil to usable products, additional processing is necessary. This brief sketch gives an idea of what this different, but significant, form of hydrocarbon is like. ENVIRONMENTS OF DEPOSITION Most oil shale deposits fall into three environments of sediment deposition: 1ake (called lacustrine), sea (marine) and river (fluvial-deltaic). In each case, the deposition of oil shales took place in quiet water environments where plant life, particularly algal plants, could flourish and, after dying, be deposited in unoxygenated water where the kerogen precursors would be safe from destruction by oxidation. The oil shales that were deposited in large lake basins (lacustrine) have attracted the most attention for development over the years. They often have multiple seams, deposited in a cyclic nature with extensive areal distribution and rapid vertical changes in kerogen content. Grades are moderate to high, ranging from 80 to 200 liters per tonne. Rundle in Australia and the Piceance Creek Basin in Colorado are examples of this type. Both deposits represent large volumes of oil shale in small areas which could provide the large volume of feedstock needed for future commercial operations. The stratigraphic sections of these two deposits feature thick oil shale seams with average grades of 80 - 125 liters/tonne conducive to both open pit, and underground operations. However, the rock strength of the Rundle shale is not sufficient to - support underground mining. On the other hand, the Colorado deposits, being more carbonate in nature, are sufficiently strong to support either type of mining depending on the overburden to ore ratio. These latter types of deposits will likely provide the first target for development of a commercial industry. The marine type is characterized by extensive areal distribution with relatively thin seams. The grades are generally low to moderate, ranging from 50 to 120 liters per tonne. The marine oil shales are common worldwide, and their attractiveness for mining is dependent on the overburden to ore ratio. Because of their widespread areal distribution, their in situ resources can be quite large. The Toolebuc Formation in Central , Queensland, Australia is a good example of this type of deposit being 7-10 meters thick over an extensive area. The Julia Creek deposit with its favorable overburden-to-ore ratio is being studied for possible development. In a fluvial-deltaic environment, there are many small lakes or bogs associated with rivers in which a very pure type of oil shale called torbanite could form. Torbanites are very high grade containing up to 75 percent hydrocarbons. The known occurrences are generally small lenticular deposits associated with coal seams. Even with the high grades, it is not likely that any of the known deposits would warrant commercial development because of their small size. The torbanite deposits in New South Wales, Australia were processed prior to World War I1 near the town of Glen Davis. However, today's known resources of this type are not large enough to warrant a commercial plant.

Jan 1, 1982

Production of crude oil in Bahrein Island during 1938 reached the new high of 8,297,998 bbl., an increase of 535,734 bbl, over the 1937 production of 7,762,264 bbl. The monthly average during 1938 was 691,500 bbl. and the daily average 22,734 barrels. To the close of December 1938, a total of 52 producing wells have been drilled. During the year 13 producing wells were completed and 11 wells were drilling or partly completed as of Dec. 31, 1938. The total footage drilled as of Dec. 31, 1938, amounted to 165,339 ft., of which 60,739 ft. was drilled during 1938. The production from the main pay comes from a depth of approximately 2200 ft. and the gravity of the oil is 33" A.P.I.

Jan 1, 1939