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By E. A. Koester

Kansas produced approximately 35,434,000 bbl. of oil in 1932 compared to 37,018,000 bbl. in 1931, a decrease of 1,584,000 bbl. or 4.2 per cent. These figures do not indicate the amount of oil that could have been made available from the state for the year. Many of the fields discovered during the year and some discovered in previous years were entirely shut in. Practically all flush production discovered within the last two years has been prorated in some manner or other. Probation Kansas production is under regulation as specified in House Bill 387, passed by the legislature in 1931, which became effective when published May 28, 1931. The principal features of the law are the prohibition of waste, including gas energy, the regulation and prevention of discrimination of purchasers, the marketing of oil ratably from wells in each field when the daily production is above 15 bbl. per well. This act gives the enforcing powers to the Public Service Commission. The Commission, having many other regulatory duties, appointed an Oil Advisory Committee, which, with the aid of the State Umpire, keeps records and makes recommendation for orders as to specific regulation of fields and conditions in each field. At the time the Commission was given authority to regulate production and marketing in flush fields, several of these had already been under voluntary proration and marketing restrictions by agreement of the operators. These gradually came under the control of the Commission by mutual consent. It is the policy of the Public Service Commission to follow the will of the operators so long as they do not have ideas or plans in conflict with the law. The cost of administration of this law is assessed against the operators according to the amount of oil taken from the fields in which ratable taking is necessary. There is a feeling that the whole state should share this expense, which is small, since it is beneficial to the older fields by assuring them 100 per cent market for their output by restricting the flush fields.

Jan 1, 1933

By Clark A. Sumner

An apparatus for agglomerating fine particles was developed in 1969 as a joint effort of Stauffer Chemical and O’Brien Industrial Equipment. Commercial sized units were built for agglomerating home dishwashing detergents. Recently, as a result of further pilot development, variation of bed depth and cage configuration has resulted in a means of controlling the amount of internal classification from a minimum, producing small agglomerates, to a maximum, producing compact rounded agglomerates. Little or no external classification of discharged agglomerates is needed. At maximum internal classification the agglomerates roll on a bed of fine particles rather than the shell resulting in increased agglomerate size.

Jan 1, 1977

By Alfred H. Bell, George V. Cohee

In 1939 Illinois produced 94,302,000 bbl. of oil—almost three times the amount of oil produced at the peak in 1908, when development in the southeastern Illinois field was at its height (Fig. I). It represents nearly a fourfold increase over the 24,075,000 bbl. produced in 1938 (Table 6). This rapid increase in oil production in Illinois is largely due to development in the Salem and Louden fields (Table I). During 1939 daily production for the state increased from 135,000 to 332,572 bbl. A notable increase in production for 1940 is expected as a result of the drilling of the Devonian limestone in the Salem and Centralia fields,

Jan 1, 1940

By Alfred H. Bell, George V. Cohee

In 1939 Illinois produced 94,302,000 bbl. of oil—almost three times the amount of oil produced at the peak in 1908, when development in the southeastern Illinois field was at its height (Fig. I). It represents nearly a fourfold increase over the 24,075,000 bbl. produced in 1938 (Table 6). This rapid increase in oil production in Illinois is largely due to development in the Salem and Louden fields (Table I). During 1939 daily production for the state increased from 135,000 to 332,572 bbl. A notable increase in production for 1940 is expected as a result of the drilling of the Devonian limestone in the Salem and Centralia fields,

Jan 1, 1940

By E. W. Krampert

The oil industry was very active in Wyoming in 1936, in contrast to the several quiet years preceding. Production for the year again increased about 7 per cent, following an 8 per cent increase in 1935. During the year, 85 oil wells were completed, compared to 55 in 1935. Three gas wells were completed in 1936, and three in 1935. At the end of the year 45 wells were drilling, as compared to 55 drilling at the end of 1935. Two new oil fields and one new gas field were discovered in Wyoming during the year. In the year 1936 Wyoming produced 14,475,431 bbl. of oil, a gain of 1,001,081 bbl. over the 1935 figure of 13,474,350. This increase, in the main, was due to the taking of light oil from the newly developed Sundance sand pool at Lance Creek, and from the new fields, Quealy and Medicine Bow, which contributed their first production this year. Most of the other old fields either were partly shut in in competition with the new fields, or showed a normal decline. This was especially noticeable in the black-oil fields, where production had been slowly but steadily increasing for a number of years. During 1936 black-oil production decreased approximately 100,000 bbl. as compared to 1935. The only black-oil field to show marked increase was Garland, which managed to take the market from less favorably located fields. The production of Wyoming in 1936 was 11,358,757 bbl. of light oil and 3,116,674 bbl. of black oil. Salt Creek, with a production of 6,015,000 bbl., is still the largest single oil-producing field, accounting for 42 per cent of the year's total production. Lance Creek, an old field, with newly developed production in the Sundance sand, reached second place this year for the first time in its history, with a production of 1,878,486 bbl. Lance Creek production will almost equal that of Salt Creek in 1937, if the present rate of production is maintained during the coming year. Oregon Basin, a large black-oil field, held second place in 1935, but owing to a greatly lessened demand for its production, dropped back to third place in 1936. This was in part due to greatly increased light oil available, and in part to the greater supply of black oil available at

Jan 1, 1937

By Frank C. Greene

Drilling in Missouri in 1945 dropped slightly from the preceding year. The only notable development was that in the Ballard area in Bates County, where a number of farmers drilled private gas wells with an average depth of a little more than 30o feet. Table 1 gives a summary of activities by counties. The total footage drilled was 36,186 ft. of which 20,489 ft. was by cable tools and 15,697 ft. by rotary tools.

Jan 1, 1946

By M. J. deBastiani, John Kostuik

The Denison orebody, located on the north limb of a syncline, rests at depths of 800 ft in the northern end of the property to 3000 ft at the southern end, and has a composite dip of 19º, varying locally from 0º to 45º. It is composed essentially of two pyritized conglomerate beds separated by a varying thickness of quartzite. The thickness of the upper conglomerate reef of the main ore zone varies from 2 to 15 ft while the lower reef is from 2 to 12 ft. Mining, whether carried out over the entire section of the reefs and quartzite or by selective mining of the reefs, is accomplished by room and pillar methods, with an initial 67% extraction on the advance towards the property boundaries. The underground ore handling requirement in such an orebody has become one of the most challenging problems in mining.

Jan 8, 1966

By Andrew S. McCraeath

The treatment which a steel receives, and the uses to which it may be applied, are frequently determined by the percentage of carbon which it contains; and especially is this the case in the different steel works in this country. The part which this element plays in the composition of steel is such an important one that a process for its accurate determination becomes an absolute necessity.

RESOLUTION ADOPTED BY THE BOARD OF DIRECTORS AT ITS MEETING ON APRIL 17, 1936 Recognizing the fact that the problems of the committee named by the Board to prepare the " official ticket" for officers and Directors of the Institute are various and difficult; and desiring to assist this committee by setting forth some of the principles that should guide the committee and some of the qualifications that should be required of candidates, the following instructions are formulated and the Secretary is directed to publish them in MINING AND METALLURGY concurrently with the publication of the names of each newly appointed Nominating Committee and to send a copy to each member of the Committee. NOMINATIONS TO BE MADE Each year the Nominating Committee is to select "official" candidates for eight places, as follows: (1) President and Director (2) Vice-President and Director (3) Vice-President and Director (4) Director (5) Director (6) Director (7) Director (8) Director GEOGRAPHICAL DISTRIBUTION The Bylaws provide that "the Nominating Committee shall, so far as practicable, distribute representation on the Board geographically." Pursuant to this provision, the United States, Canada and Mexico have been divided into fifteen districts, as shown on the official map.* Districts 1, 5, 6, 10, 11, 12,13,14, and 15 are assigned one Directorship each; District 2, three Directorships; District 3, eight Directorships; District 4, two Directorships; and Districts 7, 8, and 9, two Directorships between them. It will be the duty of the Nominating Committee to make selections that will give effect to this allocation of Directorships. There is nothing to prevent a Director being named to succeed himself. Attention is called to the: fact that many Institute members now resident in New York formerly lived in the West, South, or North and still have intimate business connections that compel them to visit various parts of the country periodically. Such men are particularly valuable as Directors and their nomination and election tends to minimize the objection that a large number of Directors reside in New York.

Jan 1, 1940

By M. E. Wadsworth, J. R. Lewis, J. M. Quets

Samples of snythetic magnetite were reduced in hydrogen at various partial pressures and temperatures. The reaction mas found to be surface controlled and directly proportional to hydrogen partial pressure over the temperature range studied (400° to 1000°C). A transition in the mechanism occurred at approxirnately 590°C. This has been attributed to a change in the slow step of the reduction reaction resulting from the presence of stable wüstite at higher temperatures. Below 590°C the heat of activation for the reduction was found to be 14,700 cal per mole and it was 3,200 cal per mole above 590°C. THE reduction of the oxides of iron has been a subject of study and interest for many years. Edstrom1 has reviewed the work up to 1953 and his findings provide much basic information concerning details of the reduction of hematite (Fe2O3 ) and magnetite (Fe3O4) with both H2 and CO. He concluded that below 600°C the reduction of both hematite and magnetite was essentially identical, since the rate was controlled by a surface reaction at a magnetite gas interface and the iron formed was very porous. The decrease in the reduction rate for both hematite and magnetite immediately above 600°C was attributed to the formation of a stable wüstite phase across which diffusion was very slow. The wide difference in reduction kinetics for hematite and magnetite above 600°C was explained in terms of the character of the wüstite formed. The rate of magnetite reduction increased slowly with temperature beyond the minimum immediately above 600°C and rates equivalent to those observed at 550°C were not obtained until the temperature was increased beyond 850oC. Edstrom and Bitsianes2 studied the solid-state reduction of magnetite, the reaction of which can be written (4x-3)Fe + Fe3O4—4 FexO [1] where x is between 0.83 and 0.95. The rate was found to be controlled by the kinetics of transport of iron ions through the wüstite phase. Bogdandy and Riecke3 studied the kinetics of reduction of small grains of iron oxide in hydrogen and qualitatively attributed the slow step in the reduction process to the diffusion of hydrogen and water vapor through pores. McKewan4 has analysed the data of Joseph,5 Stalhane and Malmburg,6 and Lewis7 and has demonstrated that the kinetics of reduction of both hematite and magnetite are controlled by surface reactions and also that the variation in surface area during reduction must be accounted for. McKewan was able to correlate the reduction data by the equation rodo[1-(1-R)1/3] = Kt [2] where ro is the initial particle radius, do is the density of the iron oxide, R is the fraction reduced at time t, and K is a rate constant. The applicability of Eq. [2] for temperatures above 600°C where a stable wüstite phase is present, indicates the slow step in the over-all kinetics does not result from diffusion unless diffusion occurs laterally along the oxide metal interface or through a wüstite layer of constant thickness. Diffusional control through a layer of wüstite is unlikely, however, in view of the pressure effects demonstrated by Tenenbaum and Joseph,' Diepschlag,9 McKewan,10 and the results of the present study. McKewan has demonstrated a linear rate dependence on the hydrogen partial pressure over the temperature range 400" to 1050°C for the reduction of hematite.

Jan 1, 1961

By Richard D. Divine

In the Parkes process of extracting precious metals from lead, zinc is added to the molten lead containing gold, silver, copper, and some antimony. These metals, with the exception of antimony, form an alloy with the zinc by reason of their greater affinity for it than for the lead, and this alloy, being lighter than lead, rises to the top, carrying the precious metals with it, whence it can be removed by skimming. These skimmings are further treated for the separation of the zinc therefrom, and the recovery of the precious metals, the zinc being driven off by heat and again used for another operation. In addition to the zinc that combines with the silver, etc., a certain amount is necessary to saturate the lead, and it is therefore necessary to treat the desilverized lead to free it from this residual zinc. TO do this it is heated again in a reverberatory furnace and air or steam is blown through it. This oxidizes the zinc together with a small amount of lead and antimony, leaving the lead free from zinc and antimony, and forming oxides of these metals, which rise to the top and are skimmed off. This process relates to the separation of the metals in these oxides or skimmings. The skimmings are cooled, crushed, and mixed with carbonate of soda and pulverized oil coke. The mixture is heated in a reverberatory furnace on a bath of lead, to about 1,000" C. The metals are reduced by the coke, the lead and antimony go into the lead bath, while the zinc is volatilized and burned to oxide. This impure oxide is at the present time treated at Omaha by the Hall process of electrical precipitation, making a very pure metallic zinc. It can also be very easily refined by the old Schnabel process of using ammonia and carbon dioxide as a solvent. It seems to be in an ideal form for this purpose, and very few changes from the original method are required to obtain the zinc oxide practically C. P., leaving the lead and antimony as residues. There has been considerable difference of opinion regarding the effect

Jan 1, 1915

By Toyohiko Hirota, Fukuo Itoh

Oil and natural gas aside, sea floor mineral resources currently being exploited in Japan are offshore sand and gravel and deep-sea manganese nodules. The mining of sand and gravel has already started. With regard to manganese nodules, the geophysical investigation and the study of the mining method are also underway. This report outlines the activity of a few Japanese firms, the Deep Ocean Minerals Association formed by some 30 private firms, Government agencies, a public corporation and two government research institutes. Researches on new exploration instruments, properties of deep-sea sediments and the mining method currently conducted by the National Research Institute for Pollution and Resources are described in detail.

Jan 1, 1976

By Martin A. Mayers

Five-sixths of all the coal that is mined in the United States is burned, without previous treatment other than screening, for the production of heat and power, so that its value is fixed by its suitability for this purpose. Nevertheless, the characteristics of individual coals that determine their fitness for use in particular pieces of combustion equipment are not yet well known. This condition is due not only to the small extent of our knowledge concerning coal itself, but also to our comparative ignorance of the nature of the combustion process. The following paper is an analysis of the combustion process as it occurs in industrial furnaces, based largely on the results of laboratory research on combustion rates. From this analysis it is possible to determine the characteristics of the fuel that limit the capacity of a given piece of combustion equipment. Limitations imposed by other factors than the attainable speed of combustion will not be considered, since they are subject to a different type of analysis involving the balancing of maintenance costs against fixed charges. In order to observe the relations among the various factors that affect the speed of combustion, representative particles of fuel will be followed through two types of furnaces. A pulverized-coal furnace will be considered first, because the independence of the individual particles facilitates the analysis of the effect of furnace conditions. The second example will be a grate-fired furnace in which ignition of the fuel takes place on the underfeed principle. This includes both underfeed and chain grate stokers, (8)† but does not include hand-fired furnaces and some overfeed stokers. The furnace will be considered to be large enough, the temperature high enough, and enough air provided, to burn the fuel completely, without, for the moment, specifying these quantities more completely. Furnaces Burning Pulverized Coal In a pulverized-coal furnace, the fuel particle is carried, in a stream of air, into the furnace, where it is subjected to radiation from the flame and from the hot walls of the furnace. The increase of particle tempera-

Jan 1, 1936

By Martin A. Mayers

Five-sixths of all the coal that is mined in the United States is burned, without previous treatment other than screening, for the production of heat and power, so that its value is fixed by its suitability for this purpose. Nevertheless, the characteristics of individual coals that determine their fitness for use in particular pieces of combustion equipment are not yet well known. This condition is due not only to the small extent of our knowledge concerning coal itself, but also to our comparative ignorance of the nature of the combustion process. The following paper is an analysis of the combustion process as it occurs in industrial furnaces, based largely on the results of laboratory research on combustion rates. From this analysis it is possible to determine the characteristics of the fuel that limit the capacity of a given piece of combustion equipment. Limitations imposed by other factors than the attainable speed of combustion will not be considered, since they are subject to a different type of analysis involving the balancing of maintenance costs against fixed charges. In order to observe the relations among the various factors that affect the speed of combustion, representative particles of fuel will be followed through two types of furnaces. A pulverized-coal furnace will be considered first, because the independence of the individual particles facilitates the analysis of the effect of furnace conditions. The second example will be a grate-fired furnace in which ignition of the fuel takes place on the underfeed principle. This includes both underfeed and chain grate stokers, (8)† but does not include hand-fired furnaces and some overfeed stokers. The furnace will be considered to be large enough, the temperature high enough, and enough air provided, to burn the fuel completely, without, for the moment, specifying these quantities more completely. Furnaces Burning Pulverized Coal In a pulverized-coal furnace, the fuel particle is carried, in a stream of air, into the furnace, where it is subjected to radiation from the flame and from the hot walls of the furnace. The increase of particle tempera-

Jan 1, 1936

By H. J. Rahilly

Mine fires, in the Butte district, have been a source of trouble and expense for the past thirty years, for while the actual fire area in most of the mines has been comparatively small, the handling of the gas has generally been a much larger problem than the actual putting out of the fire. The chief causes of these fires have been: Defective electrical equipment, incendiarism or carelessness, and spontaneous combustion. While fires from the first two causes have been numerous, they have generally been discovered and extinguished before they became very serious. Spontaneous combustion has been the cause of most of the large fires. Sufficient heat has been generated by ground movement, high rock temperatures, and decomposition to set fire to inflammable materials (tarred ropes, canvas, dry timber, manure, and hay) left in the gobs some years ago. Also, the heat resulting from the oxidation of the fine broken sulfide ore is sometimes sufficient to set fire to the timbers. In 1906, a fire was discovered on the 1100-ft. level of the Minnie Healy mine about 400 ft. (122 m.) west of the Minnie Healy shaft, which presumably originated, in one of the upper levels, from spontaneous combustion. The fire was walled off by concrete bulkheads and a pillar of ground 100 ft. (30 m.) thick was left below and mining resumed underneath. During subsequent operations, this pillar became cracked and broken and the fire passed into the new workings. It travelled downward and spread rapidly until, in 1917, it had become necessary to wall off portions of the Tramway, Leonard, and West Colusa mines on the 1300, 1400, 1500, 1600, 1800, 1900, and 2000-ft. levels, and the tops of the 2200-ft. raises were sealed. The fire area now consists roughly of a block 1000 by 1200 ft. and from the 600-ft. to the 2200-ft. level. This block is composed largely of a series of parallel northwest-southeast nearly vertical veins and stringers that form a large orebody, with no well-defined walls but badly fractured and faulted, and known locally as "horsetail ore." These veins, or orebodies, are mined by the square-set or the rill method.

Jan 1, 1923

By H. J. Rahilly

Mine fires, in the Butte district, have been a source of trouble and expense for the past thirty years, for while the actual fire area in most of the mines has been comparatively small, the handling of the gas has generally been a much larger problem than the actual putting out of the fire. The chief causes of these fires have been: Defective electrical equipment, incendiarism or carelessness, and spontaneous combustion. While fires from the first two causes have been numerous, they have generally been discovered and extinguished before they became very serious. Spontaneous combustion has been the cause of most of the large fires. Sufficient heat has been generated by ground movement, high rock temperatures, and decomposition to set fire to inflammable materials (tarred ropes, canvas, dry timber, manure, and hay) left in the gobs some years ago. Also, the heat resulting from the oxidation of the fine broken sulfide ore is sometimes sufficient to set fire to the timbers. In 1906, a fire was discovered on the 1100-ft. level of the Minnie Healy mine about 400 ft. (122 m.) west of the Minnie Healy shaft, which presumably originated, in one of the upper levels, from spontaneous combustion. The fire was walled off by concrete bulkheads and a pillar of ground 100 ft. (30 m.) thick was left below and mining resumed underneath. During subsequent operations, this pillar became cracked and broken and the fire passed into the new workings. It travelled downward and spread rapidly until, in 1917, it had become necessary to wall off portions of the Tramway, Leonard, and West Colusa mines on the 1300, 1400, 1500, 1600, 1800, 1900, and 2000-ft. levels, and the tops of the 2200-ft. raises were sealed. The fire area now consists roughly of a block 1000 by 1200 ft. and from the 600-ft. to the 2200-ft. level. This block is composed largely of a series of parallel northwest-southeast nearly vertical veins and stringers that form a large orebody, with no well-defined walls but badly fractured and faulted, and known locally as "horsetail ore." These veins, or orebodies, are mined by the square-set or the rill method.

Jan 1, 1923

By K. L. Williamson, P. W. Dugan

INTRODUCTION In recent years there has been increased social awareness and government attention directed toward the mining industry. The growing influence of the Occupational Safety and Health Administration (OSHA), the Mine Safety and Health Administration (MSHA), and the Environmental Protection Agency (EPA) has resulted in volumes of regulations governing a multitude of health and safety aspects of mining and milling. These regulations naturally have had an impact on new plant design and in some cases have necessitated retrofitting of existing plants. This paper will not examine the regulations governing the industry, since they are a matter of public record, but rather will address two specific health considerations, dust and noise, and their influence on the design of crushing and screening plants. DUST AND NOISE CONCEPTS Dust is generally defined as finely divided solids which may become airborne without any physical or chemical change except fracture. Since the purpose of comminution circuits is to reduce the size of solids by fracture, a percentage of the material is normally reduced in size to a point where it can easily become airborne. The major cause of dust becoming airborne is the air induced by falling material. When granular material falls through a distance, the induced (or entrapped) air rushes out available openings, carrying with it the fine particles that have become suspended. For this reason, the major points of dust generation are the points where the material is falling: chutes, transfer points, screens and equipment feed and discharge points. The expected dust concentration in an area is a function of the degree of size reduction (i.e., finer particles are more readily carried by air currents than heavier particles) and the volume of air that is induced. The measured dust concentration values for various operations agree with this

Jan 1, 1982

By H. Baldauf, H. Schubert

The structure of flotation reagents is important for their adsorption on mineral surfaces and thus for their flotation effectiveness. The influence of the structure of organic depressants on the flotation of fluorite and barite with anionic and cationic collectors was investigated using a modified Hallimond microflotation cell. In addition, adsorption, desorption, and electrokinetic results were employed to further elucidate the role and the correlation of the structural parameters for adsorption and the depressing effect. As hydrophilic reagents, different aliphatic and aromatic compounds capable of forming chelates with alkaline earth materials were used. For the depressing effect, the kind, number, and position of the polar groups in the molecule, as well as the structure of the reagent films play decisive roles.

Jan 1, 1980

By S. R. B. Cooke, Y. S. Kim, I. Iwasaki

lron oxides or the gangue minerals of iron ores can be made to float, depending upon the choice of collector. The selectivity of the separation is controlled by the accompanying chemical and operating conditions. In this report the findings on the general flotation characteristics of magnetite are summarized and the results are compared with those obtained for other iron oxides. Depending upon the choice of collector, either the iron oxides or the gangue minerals of iron ores can be made to float, the selectivity of the separation being controlled by the accompanying chemical and operating conditions. The mechanism by which a collector exerts preferential affinity for either group of minerals has been a subject of extended discussion. Previous investigations on the electrokinetic properties and flotation characteristics of hematite,' goethite,2 and quartz3 have demonstrated the electrical nature of the interaction of the collector with these oxide surfaces; anionic collectors are effective on positively charged surfaces and cationic collectors on negatively charged surfaces. Thus, from the differences in the electrokinetic properties of the above-named oxides, a theoretical basis has been provided for their separation by some typical collectors. Examination of the results reported for hematite and goethite shows that their electrokinetic properties and flotation characteristics are remarkably similar. It is of considerable interest, therefore, to examine similar information for magnetite, another common iron oxide, in order to consolidate the flotation characteristics of the three principal minerals of oxide iron ores. Such information is practically significant in the up-grading of both natural and artificial mag- netite produced from taconite, and in the treatment of partially oxidized magnetite ores. Information on maghemite and lepidocrocite, polymorphs of hematite, and goethite, respectively, is also of some theoretical interest in ascertaining the effects of crystal structure and of hydration in the iron oxide group. This article reports the findings on the general flotation characttxistics of magnetite, and compares the results with those obtained for other iron oxides. Experimentally, tlhe surface properties of magnetite were investigated by electrophoresis, and by measurement of the aclsorption of some typical flotation collectors. Its flotation behavior was tested by contact angle measurements and by simple flotation tests using a modified Hallimond tube. The basic information thus gathered was shown to be directly applicable to the interpretation of the results of batch flotation tests made on an artificial mixture of magnetite and quartz. EXPERIMENTAL MATERIALS Magnetite: Magnetite concentrate from Port Henry, N. Y., was further purified by fine crushing and magnetic separaiion, and was used throughout this investigation. For flotation tests the 150/200 mesh fraction was iso1ated and was cleaned by leaching briefly with warn 0.1 N HC1 followed by repeated washing with demineralized water. The final sample analyzed 71.71 pct Fe, 22.37 pct Fe" and 0.47 pct insoluble, and was stored in demineralized water. For e1ectrophoresis and adsorption measurements, the —400 mesh fraction of the magnetite concentrate was ground dry in a pebble mill. The surface area of the ground sample, as determined by the gas permeability method, was 70,000 sq cm per g. Since artificial magnetite has been reported to possess somewhat different physical properties than those of natural magnetite, it also was briefly examined. Preliminary flotation tests on a sample of artificial magnelite, prepared by reducing Brazilian hematite in a C0/CO2 mixture and analyzing 71.94 pct Fe and 23.78 pct Fe'', gave, however, nearly identical results with those using natural magnetite. It was concluded that artificial magnetite behaves similarly to natural magnetite. Samples which had been magnetically separated showed a tendency to cluster together due to residual

Jan 1, 1962

By Charles Bohdanowicz

The accompanying tables' show that in 1936 production of crude oil in Poland decreased very slightly (Tables 1 and 5), by about 1 per cent, and that gas production increased by about 11 per cent. As in preceding years, drilling (Tables 1, 2 and 3) was devoted principally to extension of oil fields in the Jaslo district (fields 1, 5 and 7) and, in a lesser degree, of those in the Stanislaw6w district (field 27). Production of crude oil is being sustained in a large measure by the deepening of old wells; besides a total number of 183 new wells completed (Table 3) about 152 wells were deepened, and in a general way the results of deepening were better than those of new wells drilled. Reserves of "proved land" have not increased as far as crude oil is concerned, but a notable extension of gas fieldsZ was attained in Daszawa (field 25) and in the Roztoki area (field 5). In the sub-carpathian zone gas fields have been proved in the vicinity of Kalusz, Kos6wJ and in the northwestern sector of that zone, between Tarnow and Lezajsk. The gas horizons of Daszawa occur in the Upper Tortonian, those of Kos6w in the Lower Tortonian (Middle Miocene). Exploratory drilling has been performed near Kalusz, and has been commenced near Kos6w and in the Tarn6w area. The Kos6w gas approaches the "wet" type. A possible gas reserve with a volume of 4,000,000,000 cu. m. (141,000,-000,000 cu. ft.) has been calculated, for an area of about 5 sq. km. of the Daszawa field, on the basis of production obtained and of decreases in pressure and their distribution. The fields of Roztoki and Strachocina (No. 12) have not yet supplied sufficient data for a calculation of reserves, which might possibly be estimated at 2,000,000,000 cu, m. (70,000,-000,000 cu. ft.).

Jan 1, 1937