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By E. H. Hamilton, H. C. Vacher

The limiting concentrations of carbon and oxygen which may CO-exist at equilibrium in liquid iron are important in determining the degree to which liquid steel may be refined before it is deoxidized. Most refining processes depend upon the oxidation of a highly carburized iron which invariably results in contaminating the steel with oxygen. The oxygen thus introduced presents many problems to the refiner, who in turn has attempted to rid the steel of this impurity by deoxidation witch elements such as manganese, silicon and aluminum. The importance of the limiting concentrations of carbon and oxygen is accentuated in view of a number of recent researches which have indicated in many instances the existence of relations between oxide inclusions and dissolved oxygen and physical properties and chemical behavior of steel. The determination of the equilibrium concentrations of carbon and oxygen existing in iron under steelmaking conditions is obviously of fundamental importance. It has been generally assumed that the product of the equilibrium concentrations of carbon and oxygen in liquid iron is a constant and that this product is directly proportional to the carbon monoxide pressure in equilibrium with the liquid iron. Hertyl.2 has computed values for this product based on open-hearth data which are all in the neighborhood of 0.01 to 0.03 (per cent. FeO X per cent. C) for temperatures in the vicinity of 1550" to 1600" C. and one atmosphere pressure. Kinzel and Egan % have attempted to determine the value of this product by exposing liquid iron to carbon monoxide at one atmosphere pressure. The value reported by them was 0.0005 at 1550" C. In order to apply certain equations to the rate of carbon elimination in the open-hearth process, Feild4 found it necessary to assume a value of 0.0102 at 1580" C. for this

Jan 1, 1931

By Rossiter Raymond

JOHN BIRKINBINE was born Nov. 16, 1844, at Reading, Pa., the eldest son of H. P. M. Birkinbine, widely known as a hydraulic engineer. The family removed subsequently to Philadelphia, where, as a young man he established with his father the office now continued by his sons, after more than 60 years. His education was received at public schools, the Friends' High School in Philadelphia, the Hill School at Pottstown, Pa., and the Polytechnic College of Pennsylvania, where his studies were interrupted in 1863-4 by service in the Union Army, which included participation in the battles at and around Gettysburg. Later, he devoted two years to work in a machine shop; and subsequently he became associated with the late P. L. Weimer, under the firm. name of Weimer & Birkinbine, operating the Weimer Machine Works at Lebanon, Pa. Much of his work was in mining, metallurgy, and blast-furnace construction. As manager for the South Mountain Mining & Iron Co. he carried on experiments with various fuels for iron-ore smelting while maintaining the furnace in constant operation. The carefully recorded results obtained were widely published, and are referred to in text-books by other metallurgists as most complete. From his Philadelphia office he was sent to nearly every State, and to Canada and Mexico, for examinations, reports, constructions or improvements in iron-ore mines, blast furnaces, iron works, water supplies, hydraulic development, irrigation projects, etc., and his engineering knowledge was requisitioned by several European corporations. A number of business trips were made to Mexico, beginning with a visit to the Cerro de Mercado at Durango, before railroads were established in that portion of Mexico, to make a critical examination and report on this "Iron Mountain." Later visits covered other localities and engineering problems, familiarizing him with the major part of the iron industry in Mexico. The late disturbed political conditions in that Republic have retarded the probable enlargement, modernization, and improvement of much of the iron and steel industry of Mexico, upon which he investigated and reported for various capitalists on both continents. One interesting subject included in these reports was a proposed electric furnace, to be operated by energy from water power.

Jan 7, 1915

By D. B. Dowling

The interest which has been aroused in prospecting for oil in the foothills of southern Alberta, and in the oil possibilities of the known gas fields situated in the less-disturbed areas, called for a much closer examination of the structure, thickness, and composition of the underlying rocks of the region than had hitherto been made. The areal geology of the larger part of the great plains was outlined by Dawson, McConnell, and Tyrrell, between 1881 and 1885. The foothill area was not critically examined at that time, owing to the time which would have been required for its proper study and the difficulty that was found in recognizing in the foothills the divisions which had been adopted in the mapping of the formations of the plains. This was due in great measure to the paucity of exposures in continuous sections of the lower divisions of the Upper Cretaceous. Since the pioneer work on the plains was published, the beds which form continuations south into Montana have been critically examined, The Canadian beds arch over the end of a flat anticline which rises to the south; and two sections in Montana, one on each side of the anticline, help to explain some of the difficulties previously encountered in the mapping of the measures found in the foothills. The index map, Fig. 1, shows the area studied, and its relation to southeastern Alberta, and to Montana. Problems of Correlation The principal difficulty experienced in correlation was in connection with the measures known as the Montana group. The beds of this group did not seem to agree in the two Montana sections. They showed the same differences to some extent as are encountered in comparing the foothill measures with those of the plains. The Montana group in Dakota and Manitoba consists of a series of shales of marine origin. In the eastern Montana section two sandstone members appear, leaving a shale member at the top and another

Jan 1, 1916

By R. E. Head

SOME mixtures of sulphide and oxide ores from the Tintic district in Utah are of a sufficiently good grade to be shipped to the smelter without beneficiation. In mining this type of ore, however, a material tonnage of ore of a similar composition but of lower grade is obtained. It is a ques-tion of economics whether such ore should be shipped with a certainty of a small return or concentrated if that would yield a sufficiently increased return to amortize plant construction and upkeep and yield a higher rate of profit than at present. It may be assumed that the tonnage of this borderline ore is constantly increasing and that eventually it will, attain such proportions as to justify plans for milling on a relatively large scale. Under existing conditions, the producer of mixed sulphide and oxide ores is not greatly concerned about the physical characteristics of his ore or of its mineralogical complexities, since his contract with the smelter calls for payment on the basis of chemical analysis. When concentration is contemplated an entirely different picture is presented. Percentages of valuable metal content must then be con-sidered in terms of minerals, for it is in the form of minerals that recoveries are made and losses sustained. In describing the performance of a given flotation mill and reagent combination, it may be stated as a generality that a specific percentage recovery of valuable elements is made. Tech-nically, however, the concentrator is really constructed and the reagents are selected to recover the valuable minerals. These considerations must be given prominence in discussing border-line ores from the Tintic district because of their physical characteristics and mineralogical composition. Because of these peculiarities they may be justly termed complex, since their lead, silver, and copper contents are each represented by two or more minerals of different chemical composi-tion and presenting widely divergent physical properties. This paper sets forth the results of a microscopic study of a type of borderline ore from the Tintic district that is now being treated by direct smelting. A

Jan 1, 1938

By J. P. Dunlop

THE fact is notable though probably little known that the United States is the only nation obtaining and distributing through its Government bureaus any data pertaining to waste metals and drosses. Some foreign governments do issue reports relating to mine or smelter production of primary metals, but none gives in scope and detail the information published now by the U. S. Bureau of Mines and formerly by the U. S. Geological Survey; and this is despite the fact that the funds annually allotted for those purposes are insignificant in comparison with allotments for the preparation of data relating to other industries of like importance. The earliest data on the production of metals from secondary sources in the United. States were contained in a press bulletin issued by the U. S. Geological Survey on Jan. 4, 1909. The information published was that for the year 1907 obtained and compiled by C. E. Siebenthal, who was one of the first to visualize the growing importance of the scrap-metal industry. The National Conservation Commission had emphasized its opinion that the known domestic supply of certain kinds of the more important metals was being rapidly marketed and that while there was no immediate cause for concern it was best to conserve such resources. Not only had there been a lamentable lack of any data regarding the quantity of scrap metals available or used but also gross carelessness and indifference in the segregation, collection, and effective use of scrap material. Siebenthal realized that even approximately correct statistics of recoveries from the more important base-metal scrap and drosses were nearly as essential to both producers and consumers as the statistics of the output of primary metals. There were not then nor are there now sufficient funds for complete collection of data, nor was it considered the province of the Geological Survey to do more than determine approximately the recovery of secondary metals for use in supplementing those given for the primary metals. Undoubtedly the first bulletins issued did not give the full output, for it takes time to establish contacts for an inquiry covering so

Jan 1, 1928

Application of Kutter's Formula to Gases Discussion of paper by F. ERNEST BRACKETT, presented at the Pittsburgh Meeting and issued, as Pamphlet No. 1578-A-F, with MINING AND METALLURGY, June. 1926. C. S. WITHERELL, New York, N. Y. (written discussion).-There is no reason to doubt that the relationship between the rate of flow and the impelling force of all fluids can be expressed by a general typical equation . that takes cognizance of all relevant factors such as density, viscosity (or its reciprocal mobility) and nature of channel-walls. Most fluids that are commonly conveyed by flow in confined channels are so highly mobile that they may be considered non-viscous, hence for these fluids the factor of viscosity does not need to appear in the equation. Water is the outstanding example of this class of fluids and its dynamic behavior has been so thoroughly investigated that proven formulas pertaining thereto, be they rational or empirical, would naturally serve as prototypes for the other non-viscous fluids. As non-viscous fluids can be classed all gases and vapors, most unsaturated aqueous solutions, gasoline, alcohol, etc. Viscous fluids comprise those that have a sluggish flow such as most. oils, tar, molasses, etc., the high viscosity of which is due to shearing resistance between molecules; a force that must be taken into account in figuring the flow of fluids of this class.

Jan 10, 1926

By R. S. Wagner, W. G. Pfann

If an electric field is applied to a conducting liquid solution, changes in concentration usually occur because of differences in ionic mobilities. A variety of ways of utilizing this effect in conjunction with the freezing process are discussed in principle. For example, if a column of binary eutectic liquid is maintained a few degrees above the melting point and a field is applied, the component solid solutions will crystallize at opposite ends of the column until the liquid is consumed. An expression for the effective distribution coefficient, k, is derived for the case of a direct current Passing through a solid-liquid interface. It is shown that k can be varied It is well known that solute distributions in crystalline substances can be controlled by careful freezing from melt or solution. It is also well known that an electric field can produce substantial changes of concentration in liquid solutions by virtue of differences over a wide range, including values outside the usual range between ko (the equilibrium value) and unity. Hence, for many systems: the efficiency of zone refining can be increased; a ko of unity can be made greater or less than unity; solutes that lower or raise the fretzing point can be concentrated at the same end of the ingot by zone refining; be made equal to unity; and the tendency toward constitutional supercooling can be reduced. The methods of field-freezing are applicable to a wide range of materials including metals, semiconductors, and ionic conductors. in ionic mobility. In this paper we discuss, in principle, some methods that combine these techniques in useful way's. The methods are designated by the general term, field-freezing. Topics discussed include separation of the components of a eutectic, crystal growth, and controlling the value of the effective distribution coefficient. The methods are applicable to a broad range of materials, including alloys, semiconductors, fused salts, and other liquid electrolytes.

Jan 1, 1962

ROBERT WOOLSTON HUNT, who joined the Institute in 1874, served twice as its President, was made Honorary member in 1919, in whose honor the Hunt prize and medal were established, and who, within a month, had received the Washington Award, died at his home in Chicago on July 11, 1923. Robert Woolston Hunt was born Dec. 9, 1838, in Fallsington, Buck County, Pa., His father, Dr. Robert A. Hunt, of Trenton, N. J., graduated from Princeton College in the class of 1824, and later from the Uni-versity of Pennsylvania. His mother was Martha Lancaster Woolston. Mr. Hunt spent several years learning the practical side of iron making in the roll-ing mills of John Burnish & Co. at Pottsville, Pa. Later he took a course in analytical chemistry in the laboratory of Booth, Gar-rett & Blair, upon the completion of which he entered the employ of the Cambria Iron Co. at Johns-town, and for them, on Aug. 1, 1860, established the first laboratory in Amer-ica forming an integral part of an iron or steel organization. In the fall of 1861 he en-tered the United States military service, and was in command of Camp Curtin at Harrisburg, serving as mustering officer for the State of Pennsylvania, with the rank of Captain. In 1864 he assisted in recruiting Lambert's Independent Mounted Company, and was mustered into active ser-vice as a sergeant, having tossed up with a friend who had also participated in recruiting the company, as to which one should receive a Lieutenant's commission. Upon being mustered out of service, Mr. Hunt returned to the employ of the Cambria Iron Co. which sent him to the works at Wyandotte, Mich., where experiments with the new Bessemer process of making steel were being conducted. He was placed in charge of those works in July, 1865, and so continued until May, 1866, when the Cambria company called him back to Johnstown to take charge of their steel business, intending at once to begin the erection of a Bessemer steel plant. The plant, however, was not built for several years, and in the meantime the Cambria company began the rolling of steel rails for the Pennsylvania Railroad, using ingots of Bessemer steel produced by the Pennsylvania Steel Co. at their Steelton works. Mr. Hunt had charge of the steel for these operations; and in August, 1867, the first steel rails made in America on a commercial order were rolled.

Jan 8, 1923

By H. M. Roche

MAGNETITE is the important iron ore of New Jersey although bog ore, limonite and red hematite were mined in sizable quantity early in the state's min-ing history. The deposits of mag-netite are found in the Highland area in the northern part of the state. These ores outcrop a broad belt 20 miles wide, extending in a northeasterly direction from Phil-lipsburg, on the Delaware River, to Greenwood Lake, at the southern boundary of the state of New York, a distance of 60 miles. The area in which the magnetite is found (see map, Fig. 1) contains 1200 square miles and the center of the area is at Dover, 40 miles west of New York City. In the general area are found 18 parallel ranges or lines of ore deposits. These ranges may be re-garded as mineralized zones in which occur orebodies that are rich enough in magnetite to war-rant mining. Usually a number of the orebodies lie one above the other in the same plane, all dipping and pitching in the same direction. Within the ranges, there may be several parallel orebodies of work-able size. The average strike of the orebodies is N.41° 30' E., with an average dip of 55° southeast and an average pitch of 15 ° to the northeast. Orebodies suitable for mining range from 6 to 100 ft. wide, as measured from foot wall to hanging wall. Their heights, as measured on the dip and normal to the long axis of the orebody, vary from 200 to 3,000 ft. The length along the pitch has never been determined by mining, al-though several of the orebodies have been worked to lengths of 10,000 ft. The grade of the ore as mined today varies from 30 to 60 per cent iron, and the gangue min-erals are chiefly silica, alumina, magnesia, lime and phosphorus.

Jan 1, 1937

By H. Ries

SPECIAL sands are those that are employed for special purposes. They have a limited use, as compared with sands for concrete and plaster. The sands discussed in this chapter are those used for foundry purposes, glass manufacture, filter beds, abrasive purposes, sandblasting, engine sand, sand for sheet asphalt, and furnace sand. These sands are almost invariably high in silica, consisting chiefly of quartz grains. In some-for instance, glass sands-freedom from ingredients other than silica, such as iron oxide, is important. Certain grades, like filter sand, require rather careful sizing, and in foundry sands the bond, usually clay, is important. One deposit may sometimes be used to supply several grades or types of sand by appropriate methods of screening and washing. The special sands discussed here are usually obtained from deposits of unconsolidated material but sands high in silica are derived occasionally from soft sand- stones that can be disintegrated easily. Requirements are not the same for all uses, and, while certain properties may be demanded, there are no officially adopted standard tests except for foundry sands. FOUNDRY SANDS Definition-Foundry sands include those siliceous sands that are used to make the forms for casting metals. If these are employed for making molds, they are known as molding sands; if for the cores that form the hollow spaces in the casting, they are called core sands. Naturally bonded sands are those containing a variable, though not usually large, amount of clay, which serves as a bond. Synthetic sands, now much used, represent an artificial mixture of sand with usually fire clay or bentonite. Core sands may be bonded with oil, cereal binders, resin, pitch, or other materials. The foundrymen apply the term "sharp sand" to one that is free from bond. Properties-The important properties to be tested at room temperature are texture or fineness, permeability, strength, deformation, and flowability. Those tested at elevated temperatures are compressive strength, expansion and contraction, sintering point, and durability. More attention probably has been given to research on the properties

Jan 1, 1949

By Edward M. Weiss

THE emphasis in some political quarters on hemispheric unity and defense indicates Latin American mineral resources should be more extensively developed. However, United States mining companies have, in many instances, been discouraged by the laws of southern neighbors. At the same time, some of the countries have liberalized their mining laws in an effort to attract investments from the United States. The resultant confusion has been detrimental to all concerned. Ownership of Mineral Deposits Examination of the mining codes of Latin American countries shows that, without exception, governments reserve the right of direct ownership of all mineral resources. Ownership can be divided between the Feredal Government and the states or among the Federal Government, the states, and private individuals. However, in the majority of the nations constitutional authority vests all mineral rights solely in the Federal Government. Mexico is the only country that has expressed Federal ownership as imprescriptible; the other republics have not defined the exact significance of government ownership. The implication derived from the general economic and political climate is that all mineral resources are ultimately to be regarded as a national heritage. Whether a concession granted to an individual or corporation carries any right of private property is shaded with a variety of meanings. The exceptions at one extreme are Argentina and Bolivia, whose laws state explicitly that a concession granted to a juridical person is an act of the state, and the land becomes the private property of the individual, and the concessions constitute real property. However, in Mexico mining concessions or grants do not create rights of fee-simple ownership. The concession only conveys the exclusive right to explore, develop, and work the deposits. The mining property remains the property of the state. In some instances exploitation concessions represent a compromise between private and government ownership. In Honduras the period granted to a mining enterprise is fixed at 90 years. At the end of that time, the enterprise and all installations revert to the state without compensation.

Jan 1, 1952

By Lillian Erskine

WHILE brass and other copper alloys have long been listed as offering health hazards to their workers, it is questionable if the metals involved are alone responsible for the trades' records of morbidity. The entire science of foundry sanitation is the product of the past two decades; and the best standards now operative would have been regarded as little short of revolutionary prior to 1910. The special handicap to the conservation of the health of the brass founder's employees has been the fact that, unlike the iron founder, his business could be profitably carried on in almost any small and unsanitary quarters. As a result, writers on occupational disease have accepted brass chills or brass founders' ague as an inevitable feature of the trade; and respiratory disabilities, as well as phthisis and disturbances of the nervous system, are also included as prevalent among those employed. While there can be no question as to the basic accuracy of past investigations, there is every reason to doubt the necessity for an undue percentage of ill health among brass molders and casters who are safeguarded by scientific ventilating standards and by improving personal habits of sobriety. There is, however, need for a campaign of education as to the most approved practices and equipment whereby the employer may safeguard the health of his workers, and thereby reduce his labor turnover and increase his productive efficiency. Broadly speaking, copper, tin, and aluminum carry negligible health hazards. The toxic qualities of lead, however, are a menace; especially if scrap lead is recovered or bought for foundry processes. The rapid volatilization of zinc renders its fumes and flocculent condensation the chief problems in conserving the health of the brass worker. The frequent presence in the foundry air of traces of arsenic compounds, lead

Jan 2, 1919

By Howard S. Bryant

Kansas maintained its fourth position on the list of all oil-producing states, for the ninth consecutive year. Total crude-oil production during 1935, as reported by the Oil & Gas Journal, was 53,364,446 bbl. on 97 per rent tank table calculations. This represented an increase of 17 per cent over the production in 1934, which had been the all-time peak of production in Kansas up to that time. Many of the 51 new discoveries of the year, listed in Table 2, did not have a pipe line outlet until about January, 1936; therefore did not contribute to the 1935 production of the state. The potential of all wells in Kansas at the end of the year was 998,-000 bbl. per day, and the daily allowable was 143,000 bbl. per day, showing proration to the extent of 14 per cent of capacity, under the rules of the State Corporation Commission. Several important new pipe lines were built into western Kansas by extending older lines from east to northwest, providing additional outlets for new crude-oil production, and increasing the service facilities from the older oil fields. The crude-oil price level remained unchanged throughout 1935 as it did in 1934, the price of Kansas 36" gravity crude being quoted at $1 per barrel. However, on Jan. 9, 1936, the price of this gravity oil was raised to $1.10 per barrel. Following the trend of the past several years, drilling activity was largely in western Kansas, and showed a still farther westward push from last year. A relatively high percentage of successful wildcat wells at a relatively shallow drilling depth, combined with the expiration of leased acreage assembled before the depression, caused the rapid exploration and development campaign, begun in 1934, to continue. This has caused the opening of more new fields in 1935 than during any previous year in the history of oil production in Kansas. A summary of the results of drilling in western Kansas is given in Table 2. Eastern Kansas had considerable drilling, showed six new fields or extensions of oil fields, but in the limited space of this paper such developments cannot be described.

Jan 1, 1936

By T. B. Counselman

AFTER several years study, the Universal Atlas Cement Co. decided to rebuild its plant at Leeds, Alabama. The entire old plant, which was to operate during the new construction, was then to be scrapped with the exception of two kilns. The quarry was to be mechanized, new and larger kilns installed, with the most modern type of equipment all through the plant. Raw grinding operations at all of the Universal Atlas plants were dry. However, the dust hazard of this operation and the growing emphasis on occupational diseases made wet grinding attractive. Coal at Leeds is cheap, so that a slightly higher coal practice was unimportant. Power was cheap, so that waste-heat boilers were not desirable. Since new kilns were to be installed, these could be made long enough to make filters unnecessary. Wet raw grinding could be either the old practice of open-circuit compartment mills or closed-circuit grinding in accordance with metal-lurgical practice. The latter saved power and steel wear and saved initial investment. This had been demonstrated in cement plants. Also, the elimination of tramp oversize was a most important advantage. Ease of chemical control was another factor. Blending in the thickener, with elimination of slurry mixers had been found practicable. Therefore, if wet raw grinding were used at all, the advantages were clearly in favor of closed-circuit grinding. Detailed layouts of the most modern possible closed-circuit dry-grinding plant and of a closed-circuit wet-grinding plant were prepared, and careful estimates were made of initial invest-ment and operating costs. Full consideration of all the factors involved resulted in a decision to install wet closed-circuit grinding.

Jan 1, 1939

By Carl W. Volz

NORWAY'S metallurgical development, which has extended over many centuries, is intimately associated with that country's unique topography and climatic conditions. It is a rugged mountainous country, with a most irregular shore line, bordered by thousands of islands forming a natural protection for shipping. There are an endless number of lakes, and innumerable rivers and waterfalls, many fed by glaciers and melting snow. Rainfall is abundant. Though half of the country is north of the Arctic Circle, it is warmed by the Gulf Stream, so that the average temperature is about 45°, or 20° higher than other parts of the world in the same latitude. A sub-

Jan 1, 1935

By R. D. Sprague, C. B. Richardson

The year 1938 was the most active and successful in the history of the oil industry in southern Louisiana. Drilling showed a 16 per cent increase over that of 1937, with a total of 538 wells drilled, which yielded 315 oil wells, 19 distillate wells, 4 gas wells and 200 dry holes. Nineteen new fields were discovered during the year, all but three of which were completed by plugging back to sands previously drilled through. Electrical logging played a large part in these new discoveries as well as in the discovery of new sands during routine development of fields. Fourteen of the new discoveries produced oil, and five produced only gas and distillate. Southern Louisiana continues to lead the world in depth of drilling, which is in part due to the great thickness of comparatively young deltaic sediments near the coast and the existence of numerous sands. The present development is rather evenly distributed over a coastal strip 100 miles wide. New Fields North Tepetate, Acadia Parish.—Atlantic Refining Company's No. 1 Klumpp was completed for a new field through perforations from 7960 to 7970 ft. The initial production was 65 bbl. of 54" gravity distillate and 4 million cubic feet of gas daily through a 1/4-in. choke with tubing pressure of 2850 Ib. and casing pressure of 2930 lb. The well is in see. 12, 7 S., 2 W., just north of Tepetate field. It was drilled to a depth of 8705 ft. and plugged back for its final completion. Atlantic's NO. 2 was completed in a new sand at 8300 ft., also for distillate. South Crowley, Acadia Parish.—Humble Oil and Refining Company's No. 1 Boyd Finch was completed in July 1938, as an oil well through perforations from 7318 to 7325 ft. after plugging from a total depth of 10,222 ft. After making several hundred barrels of oil, the well went to

Jan 1, 1939

By D. L. Katz

In the management of oil properties, it is always desirable to know the future behavior of oil wells and oil reservoirs. Some estimation of the quantity of oil and gas that will be produced must be made as a basis for decisions on possible returns on investments in lifting equipment, drilling of additional wells, and other operating expenditures. In new or wildcat areas, operating expenditures are considered highly speculative, but in the completion of partly drilled and the operation of producing fields it is good business to remove as much speculation as possible. An accurate knowledge of oil and gas reserves in such cases would solve many management problems. The term "oil reserves" usually signifies the future ultimate recovery without specifying the method of production. Thus with changing methods and innovations in the production industry, reserves of any definite reservoir may be increased by increasing the portion of oil recovered. The usual reserve estimates are made by comparisons of well and formation characteristics, by using a percentage recovery on the oil content of the formation volume using porosity data, by extending production curves on non-prorated wells, or by extending bottom-hole pressure-production curves. The most reliable method would appear to be one that would estimate the initial quantity of oil and gas present and then obtain percentage recovery values for various productive methods and formations from experience. It is the purpose of this paper to describe a method of estimating the initial quantity of oil and gas present in a reservoir. The method is based on field operating data and the properties of crude oil-gas mixtures. The principles involved, the data required, the assumptions necessary, and an example of the method will be given. The method is entirely independent of sand volumes and formation porosities. Principles of Method The method of estimating the initial quantity of oil and gas present is based upon the premise that the volume occupied by oil and gas in the reservoir is constant and that a mixture of crude oil and gas will behave in

Jan 1, 1936

By J. M. Morris

The point to be made most clear in this paper is the economic value of flotation in the Benguet mill flow sheet. It is rather a statement of effect with no attempt at a technical explanation of the cause. Certain well-known, easily understood reagents, mechanisms and principles have been adapted to the conditions at Benguet, and have proved to be more successful than was demonstrated in the laboratory. The mechanical and metallurgical development of this particular operation was arrived at by trial and error, with fortunately very little error. Changes were slow, of necessity, which in the end proved a blessing in that time was afforded for observation and analysis of the disturbing factors; and as a result each change was a definite step towards higher efficiency. Many of these steps were unpredictable from laboratory work because of the varied and differing characteristics of ores met with in daily operation of the mill, which were practically impossible to reproduce on a laboratory scale. The Benguet mill receives daily ores that differ as much as if they were delivered from three different properties. There is first the surface and upper-level zone, which produces an oxidized secondary ore containing considerable iron oxide, manganese oxide and some organic matter. Formerly, most of this ore consisted of very soft fill with some hard rock mixed in. It also contained an unusual amount of iron and aluminum sulfate, which formed hydrates upon entering the alkaline cyanide solution and caused excessive frothing. When flotation was introduced in the Benguet mill the general characteristics of this upper-level ore had changed considerably, in that it was practically all newly mined, fairly hard ore. It still contained many of the same disturbing elements, but was somewhat simpler to treat than formerly. The small proportion of fines is still troublesome in flotation, and plant practice probably does not show more than 80 per cent extraction on this small portion of the ore. No definite figure on this is available, as this particular ore is delivered at irregular intervals

Jan 1, 1939

By Richard Ely

Conservation Means Preservation, Improvement, Justice CONSERVATION, narrowly and strictly considered, means the preservation in unimpaired efficiency of the resources of the earth; or in a condition so nearly unimpaired as the nature of the case, or wise exhaustion, admits. And broadly considered, it means more than the word itself implies, for it naturally includes an examination of methods whereby the natural inheritance of the human race. may he improved; and still more broadly considered-and as used in popular discussion-it includes a treatment of the effects of productive conservation measures upon distribution. We shall give our attention briefly to the main points in this informal definition before we pass on to the thesis that conservation is largely a matter of property relations-that a wise conservation policy means wise property relations. Preservation of Natural Resources First, conservation suggests simply preservation, and, in the treatment of the subject which we have had in the United States, emphasis has been laid upon the past and present waste of natural resources and upon the means of putting a stop to this waste. The forests have been depleted; soil has been washed by rapidly flowing surface water from mountain sides. These rapidly flowing waters have produced high streams and devastating inundations, followed by low streams and impeded navigation. The forests have, moreover, been so removed as to bring great danger of fire, and destructive conflagrations have resulted in large waste of resources, including in some cases a destruction of the humus, supplying essential elements in the fertile soil. As a remedy we must have measures to reforest mountain sides, and this means large social control, very frequently taking the form of public ownership and management; but in addition we always find actual and proposed

Jan 2, 1916

By Henry Siegmann

HISTORY OF PRODUCTION AND USE In 1899 the consumption of fluorspar in the United States was reported as 16,000 tons. The invention of the open-hearth method of steel manufacture, plus the beginnings of a fluorine chemical industry, pushed consumption of fluorspar to 250,000 tons by 1918. In contrast to these consumption statistics of the past, the most recent statistics available (1972) indicate a total fluorspar usage in the United States of 1.352 million st (Table 15.4D.1). Fluorspar remains the world's cheapest source of fluorine, and its unique properties make the mineral the most desirable fluxing agent for steel refining. The linking of fluorine with carbon in the late 1930s resulted in the production of fluorocarbon, and constant growth in production over the years has formed the backbone of a strong fluorine chemical industry. For example, in 1972 it is estimated that total fluorocarbon production amounted to 2.113 million tons, and that, in this process, over 1.351 million tons of acid-grade fluorspar was consumed. The producers of primary aluminum long have been concerned about the fast dwindling reserves of natural cryolite. They found the solution to their problem by utilizing fluorspar for the manufacture of synthetic cryolite and aluminum fluoride. Nuclear weapons, as well as the growing number of peaceful uses for atomic reactors, constitute a market for uranium hexafluoride. This chemical and chlorine pentafluoride, used as an oxidizer with rocket fuels, are products that are as much a novelty as fluorocarbons were 25 years ago. Judging from past success in the field of fluorine chemistry research, it is safe to assume that the market for these chemicals will grow in the future. Three major industries account for the bulk of the fluorspar consumption: steel refining, fluorine chemical, and primary aluminum production. These industries have had a pattern of fabulous growth in the past, and their future plans point to a continuation of this pattern. It seems logical that the fluorspar usage also should continue its upward trend. Considering the growth of the fluorspar industry since 1899, and the obvious dependence on imports of fluorspar as a raw material, one of the most puzzling aspects of the past has been the apparent lack of coordination between fluorspar production and fluorspar consumption. A few authoritative voices have spoken out concerning the need to expand fluorspar production in order to meet consumption of the future. During World War II, the U.S. Government took positive steps in this direction by authorizing purchases at attractive prices for its "stockpile program." As a consequence, new fluorspar producing facilities were built, not only in

Jan 1, 1976