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By Louis Ware

BEFORE the war we often heard the term "Big Business." And there were complaints of the ills and abuses attributed to bigness in business. Although there were examples where the small businessmen spoke for their rights and sought protection from the bigger ones, it has only been in recent war years that a tendency has developed definitely to divide the business of our nation into the big and the small. In some cases, those with an eye to the political value of the vastly greater number of small businessmen of the country have fomented this division by hurrying to the protection of these more numerous voters, and intentionally or not have emphasized in their writings and verbal attacks any and all differences of these interests that could either be found or fabricated to, suit the occasion. It has become another example of breaking the people into classes and thus setting up the basis for the claims of one class against another, and the subsequent demand for legislation and Governmental aid. The terms "big" and "small" are purely relative. One businessman, employing a hundred men, told me recently he did not know which adjective would be more appropriately applied to his operation. He did not know whether he should join the small operators' group that had been organized, or should consider himself big. He said that his present plant seemed big to him when he looked back to its humble beginning many years ago with a couple of men in two rooms. Yet, when compared with many of his competitors who employ thousands, his was small. He did add, however, that he probably became big one day a few years ago when the union moved in and organized his employees.

Jan 1, 1945

By F. Louis Grammer

The following study of flue-dirt and the influences controlling it may be interesting to many. It is published because it represents observations at about thirty furnaces at different times. It may assist in giving an impetus to the making of similar observations elsewhere. Until ten years ago, the metallic waste in furnace-gases was not considered a problem of pressing urgency in iron metallurgy—certainly not in the blastfurnace end of it. Many plants at present ignore, or pay but little attention to, top-pressures. Prior to the introduction of Mesabi ore, the losses in escaping gases, if considered at all, were regarded as thermal losses, or losses of fuel (except by those interested in lead, zinc, silver, etc.). In a high-priced material like ferro-manganese, such losses were, indeed, considered important. But the behavior of the Mesabi ores, corning, as they did, in practically inexhaustible quantities, could not be disregarded by the furnaceman. These ores came to stay. The tables appended below have purposely been altered to disguise the plant, the company and the ores used. The comparative values are maintained. In these tables, the influencing elements and conditions which are constant, or practically so, namely, size of furnace, quantity of wind, fuel used, etc., are not mentioned. The figures represent observations consistently followed up for a long period. The weights of flue-dirt were obtained from cars on which no other dirt was thrown. The analyses and calculations are based on the best of sampling. The effects of slips are excluded. Slips should not occur at well-regulated or properly-constructed furnaces, excepting under unusual and rare conditions. Allowances are made for moisture, scrap charged and silicon in the metal. The cutting effect of Mesabi

Jan 1, 1904

By G. E. Kedzie

The ore-deposits of ail that portion of the San Juan country within the borders of Ouray County are either in the tertiary ernptives or, confined to a relatively narrow zone, in the sedimentary beds just beneath them. The ore-deposits in the igneous formation

Jan 1, 1888

By J. K. Stanley

It has been known for many years that the magnetic properties of a ferromagnetic material are very sensitive to internal strain. Any structure-sensitive property such as ferromagnetism, which is a function of the regularity of the atomic arrangement, and discontinuities such as grain boundaries must show deviations from an equilibrium state when the regularity of the lattice is disturbed. Experience has shown that such distortions have a marked effect on the magnetic properties of a ferromagnetic material. The purpose of this paper is to show the feasibility of using magnetic methods in detecting internal strains. More specifically, it will be shown how such properties as permeability, rema-nence, and coercive force change on cold-working of aluminum iron and how these magnetic properties change during the annealing below the recrystallization temperatures. This work was conducted for two reasons. One was the desire to see in what manner strains are relieved in aluminum iron at low temperatures—a subject of practical importance in soft magnetic materials—and the other was the feeling that a study of cold-working and strain relief might shed some light onour understandingof what takes place in the deformation of metals. Definition of Terms It is necessary to define the terminology used in this Paper because magnetic nomenclature is usually unfamiliar to the metallurgist, and certain other terms, such as recovery, have been used ambiguously by metallurgists and others. Magnetic terms are best explained by reference to the common hysteresis loop of ferromagnetic materials (Fig. I). In Fig. 1 the coordinates are magnetic induction, B, (ordinate) and magnetizing force, H. (abscissa). The c.g.s. unit for the magnetic induction is the gauss, the number of flux lines per square centimeter, and the unit for the magnetizing force is the oersted, the number of lines of force per centimeter in air or vacuum. If one starts with a completely demagnetized specimen and magnetizes it, a typical virgin magnetization curve beginning at the origin is obtained. This curve is also the locus of tips of a family of smaller hysteresis loops. From this curve it is to be noted that the induction is not proportional to the magnetizing force, and that it appears to approach a limiting induction called the saturation value, and does so for values of H of 1000 oersteds. The ratio of the magnetic induction (gauss) to the magnetizing force (oersteds) is called permeability, . Thus u= B/H and if the magnetizing force H (oersteds) is specified as ro or 100 oersteds, the permeability is written as or l00 This is the accepted notation, and will be used in this paper. The values of permeability for H = 10 or I00 are chosen as indices for 106

Jan 1, 1945

Development: Iron Ore In Peru Utah Construction Co., of San Francisco and a Peruvian Government corporation have signed an agreement for development of a large iron orebody in Peru. Most tests show 60 pct iron or better. Most of the ore is magnetite. Although ore will be shipped mainly to Eastern U. S. blast furnaces, shipments to the West Coast may develop as the orebody opens up. The construction firm indicated three American steel companies have shown interest in the project. The orebody is located 300 miles south of Lima and about 15 miles from the coast at the same longitude as New York City. Allen D. Christensen, executive vice-president of Utah Construction noted that the distance is shorter between Peru and the East Coast. The ore deposit measures about four to five miles in one direction and 10 miles in the other. As many as 15 outcroppings within these limits have been reported. Several of the outcroppings are thousands of feet long by several hundred feet wide, Christensen said. Shipments between 100,000 and 200,000 tons of ore per month are projected by the company. Cost of opening the mine to production may go over $5 million, Christensen said. It would include building of docks for ocean going vessels, housing, and heavy duty mining and processing equipment. The contract with the Peruvian government gives Utah Construction six to eight months for additional tests and a 20 year concession for mining the orebody. Peru will collect royalties on all ore. The company will also supply about 300,000 tons per year for an electric furnace to be installed by the Peruvian Government at Chimbote. No steel is produced in Peru now. Utah Construction formed the Argonaut Mining Co. last year, and was shipping iron ore from British Columbia to Japan at a rate of more than 50,000 tons a month, before winter weather decreased operations.

Jan 1, 1952

"The Tooele plant is situated at the mouth of Pine Canyon, five miles northeast of Tooele City. The site forms one terminus of the Tooele Valley railway, which runs southwest through Tooele City to Warner, a station on the Los Angeles and Salt Lake Railroad, thirty-five miles southwest of Salt Lake City.An aerial tramway, four miles in length, crosses the Oquirrh Mountains and connects the plant with the Bingham district.The plant consists of a lead-zinc flotation concentrator, lead smelter and copper smelter.SAMPLING MILL The mill is a standard Taylor and Brunton sampling mill, built in two sections, each with a capacity of 100 tons per hour. The building is of steel and concrete, 40x84 feet. A well-equipped pulping, sampling and drying room is attached.All ore is sampled here and then distributed by conveyors to cencentrator, lead smelter and copper smelter bins.CONCENTRATOR This flotation mill is arranged in two units of 500 tons capacity each, one equipped with Callow pneumatic flotation cells, the other with Mineral Separation sub-aeration machines.The feed is maintained as uniform as possible by bedding, after coarse crushing at the sampling mill. Standard practice of ball mill grinding and classification is followed."

Jan 1, 1925

By E. P. Pfleider

Important economic planning by industries, companies, financial firms and governments is predicated on estimates of future growth potential. Prior to the passage of the Taconite Amendment by the people of the State in November 1964, various admittedly conservative forecasts were made of the future of Minnesota's iron ore industry. Since that date, 3 new taconite plants are under construction, 2 are being expanded, one has just gone "on stream," and a seventh is in the design stage. These plants have a total capacity of about 35 million tons of pellets annually. The pessimism of 1964 today is being replaced by unbounded optimism. In the light of such recent developments, it becomes essential to update forecasts related to production, employment and capital investments. New projections show 50 to 58 million tons of pellet production from Minnesota by 1975. This tonnage, together with some 6 to 8 million of natural ores, should provide an annual full-time employment of 15,000 by the mining companies, plus 700 in related railroad and power producing activities and 1000 in plant construction. Total capital investment in new plants should reach $1.5 billion by 1975 and $2 billion by 1990. These current estimates indicate that the conservative goals as set in 1964 for the year 1990 should actually be achieved by 1975 or 1980. BACKGROUND Various forecasts1,2,3 have been made of the future consumption and production of iron ores within the United States. The most recent of these is by Harrison,1 delivered at the American Mining Congress meeting in Las Vegas in October. His estimates reflect the latest iron ore developments on a world wide front as well as the accelerating trend toward pellets. Minnesota's Natural Resources council prepared a detailed report in 1964 outlining the various factors that affect the future of Minnesota's iron ore industry. It presented estimates predicated on the

Jan 1, 1967

AlFred JamEs," London, Eug.:—I thank you, gentlemen, for Sour kind invitation to address you. It is a very great pleasure for me to be here at your annual meeting, and, although I have been a member since 1894, this is the first opportunity I have

Jan 1, 1909

By W. M. Myers

MINERAL Economics is the most recent profession to be recognized as a separate division of the mineral industries. It has originated from the increasing awareness of the importance of the economic aspects of industries concerned with discovery, extraction, and utilization of minerals. It is concerned with the interrelated fields of economics and technology. The individual trained in economics alone cannot qualify. The curriculum in the School of Mineral Industries at The Pennsylvania State College was approved in May 1946, and enrollment begun in September of that year. Due to the transfer of advanced students from other courses, particularly metallurgy and electrical engineering, it was possible to graduate the first seniors in June 1947. The next class was graduated in February 1948. From experience derived from placing these graduates in industry, and from information supplied by prospective employers, valuable data have been obtained in the organization and operation of the course of study.

Jan 1, 1948

By Henry E. Wood

Cleveland Meeting, October, 1912.) IN my opinion, the concentration of minerals by flotation is the most interesting problem in ore-dressing, and will command eventually far more consideration than it has at present. For many ores it furnishes a complete method of concentration absolutely independent of specific gravity, and thus simplifies the milling of many difficult combinations. Not having to recognize the influence of specific gravity, we are also able to dispense with some of the complications resulting from classifying-conditions. Where flotation cannot be used for a complete separation of the minerals from the gangue, it will be found, in nearly all cases, to save those portions which are generally lost by reason of their fine state of division. For this reason, it should be looked upon mainly as an aid to general concentration, although there are many ores so well adapted to flotation that more than 90 per cent. of the valuable metals can be recovered from them in one operation by this process. In presenting the results of my investigations in. flotation, I have endeavored to theorize as little as possible. That side of the subject has been extensively discussed by others. My earliest work with flotation was done in 1895, when I used various oils, grease, soap, etc., with results that were remarkable. I did not realize then that with water alone equally good separations could be made. Up to 1906, my endeavors were confined to attempts to keep the concentrates on the tables well wetted and away from exposure to the air. In common with others, I observed that when there was any obstruction in. the wash-water on the table of sufficient size to divert the water to either side, the concentrates collected, and, on exposure to the air, would promptly float away. This convinced me that the sulphides were all good " swimmers," and that if,

Nov 1, 1912

By B. Paul, C. C. Fu

Experiments indicate that the fatigue limit of various drill steels becomes vanishingly small in the presence of water and other corrosive liquids. Therefore one must generally expect fatigue failures of drill steels in a great many field operations. However, it is theoretically possible to so choose the hammer impact speed of a percussion drill in order to maximize the total length of hole drilled before failure occurs. In this paper the existence of an optimum speed is demonstrated and it is shown to be comparable to presently used piston speeds. The influence on drilling speed and hole length of a number of other pertinent design features, such as bit geometry, hammer geometry and steel properties is also established. Although machinery should be designed to obtain optimum performance, it is not always clear just what performance characteristic is to be optimized. For example in a rock drill it would be desirable to optimize all of the following characteristics: drilling speed, bit life, steel life, total length of hole drilled before failure, and efficiency of energy conversion. The word failure could signify excessive bit wear, bit fracture, steel fracture, or some other type of component failure. It is not possible in general to optimize all performance criteria simultaneously. For example, one could achieve fantastically large drilling rates at the expense of bit or steel life, energy requirements and physical size of system. It therefore becomes necessary to compromise requirements in order to achieve a well-balanced albeit non-optimum design. It is, however, extremely useful to explore the interrelationships between the different performance characteristics. Such a procedure would help to establish theoretical limits of performance within the framework of existing knowledge and also serve as a practical design procedure for special applications where a particular performance characteristic is of greatest concern to the user (e.g., steel breakage might be especially undesirable in certain locations). It is the purpose of this paper to examine the problem of how one may drill the deepest possible hole before breakage of the drill steel occurs. Of course the problem is almost trivial if a well defined fatigue limit (endurance limit) exists for the drill steel. In such cases one merely keeps the piston impact speed sufficiently low to insure that the stresses in the steel never exceed the fatigue limit, thereby achieving an infinite life. If, however, no definite fatigue limit exists, as seems to be the case in the presence of even mildly corrosive agents such as water (see later discussion), then a finite life is inescapable and one can at best hope to maximize the useful life of the system. Indeed it will be shown that the system life is related to drilling speed in the manner shown schematically in Fig. 1-a. Even if a definite fatigue

Jan 1, 1965

By F. M. Lewis, J. F. Meyers

This second progress report of grinding presents comments regarding ball consumption and data pertaining to the hydroscillator, which is closed circuited with the tricone mill. A study and postulate of how balls function is presented. The paper summarizes cost reduction obtained by the method of "grinding for the tail race" rather than for "mesh tons." AT the Regional meeting in Columbus, Ohio, in September 1949, the authors presented a progress report of the first year's operation with a Hardinge tricone mill in closed circuit with a Dorr hydroscillator. The present report covers our findings on this grinding circuit to January, 1950. In order to clarify our position, the authors wish to state that no invention or discovery is claimed. The Tennessee grinding circuit is simply an engineered arrangement of known equipment arranged to incorporate all of the recognized efficiency factors of comminution as they are known today. As we concluded our first report, it was not clear how effective the Tennessee mode of operation would be on harder ores. The only information we had at that time was that the Bond grindability test at 48-mesh gave 6.04 g of undersize per revolution. A later test on the same sample at 100-mesh reduced this to 2.04 g, which is definitely in the harder ore class, and which makes the reported 8.80 kw-hr per ton of —200-mesh produced a very creditable figure. Hydroscillator Operation The machine as now developed has proved dependable and easy to operate. It starts easily under full load and responds quickly to operating adjustments. The hydraulic holes in the oscillating plate do not plug when shut down under full load. Absolutely clean hydraulic water is essential. An Elliott water screen or similar device should be an essential part of the machine to keep all scale and trash of all kinds from the hydraulic compartment. The shift operators have expressed approval of the machine. In table I we show a typical screen analysis of the hydroscillator rake sand as compared to conventional classifier rake sand on our ore. We have previously reported that of the 28.7 pct reduction in power, the hydroscillator contributed 6 pct, on a —200-mesh basis. This is a conservative figure. Some of our test runs indicated that the saving was as high as 10 pct. Laboratory studies by the Dorr Co. engineers indicate that still greater efficiency is possible. Nevertheless, the 10-ft plate is overflowing 2100 tons per day at 3 to 4 pct + 65-mesh, which is a very creditable performance by

Jan 1, 1951

By Simon D. Strauss

What are future prospects for U.S. mining? In many quarters the assumption is made that this country has passed its zenith as a mineral producer -- that it is in a period of decline and that it is becoming a have-not nation like Japan and much of Western Europe. These industrial rivals of ours must depend almost entirely on others for their mineral supplies. In trying to answer this question one must of course distinguish between resources and productive capacity. In today's volatile and competitive markets, the definition of what are reserves and what are merely identified resources becomes ever more difficult. Many large deposits have been found that are unlikely to be viable in the marketplace under normal conditions but that can be of significance to the nation's military and industrial security in times of emergency. I should like to draw on personal experience from World War I1 for illustration. 4fter Pearl Harbor great concern developed over the availability of a long 1ist of strategic materials for which this country was largely dependent on imports. Included were a number of minerals of which domestic deposits had been identified. Among these were chromite, manganese ore, mercury, mica and tungsten.

Jan 1, 1982

By I. J. Jansen

Introduction The Surface Mining Control and Reclamation Act (PL 95-87) lays a new challenge before the surface mining industry by requiring that prime farmlands must be reclaimed to equivalent or higher levels of yield as nonmined prime farmland in the surrounding area (section 510d). We must now evaluate the situation and plan a mining and reclamation program that will achieve that objective. We must recognize that soil and land needs vary with intended land use and climatic setting. Also, various site conditions determine the potential for constructing a productive soil and the best procedures to accomplish that end. It is necessary to plan the land reconstruction program on a site by site basis in order to achieve the best results. Discussion The Prime Land Concept Terms like prime agricultural land have been used loosely for many years to refer to lands that are highly productive and well suited to agricultural use. The concept of what qualified as prime land varied considerably from one geographic area to another and from one person to another. The term prime farmland, as used in PL 95-87, has recently been defined quite

Jan 1, 1982

By Stirling Huntley

With the threatened falling off in production of the lighter oil pools of the Tampico embayment in Mexico, a general search of that country for oil-producing regions has resulted in renewed activity in the region of the Isthmus of Tehuantepec, one of the first districts exploited in Mexico. Since the drilling of the first well in the San Cristobal section by the Pearson interests in 1902, drilling has been continuous, except during 1917-1921, when practically all development was stopped by the revolutionary activity. Early in 1921, a drilling campaign was inaugurated for the purpose of testing out the known salt-dome poolfi on the flanks of the salt masses, rather than on their tops where previous tests had been located. On Dec. 7, 1921, the Aguila Co., with which are consolidated the Pearson interests and which has been the only company active in developing this region, unexpectedly drilled into a sand horizon at 3015 ft. with its Conception well No. 18. The hole was unable to handle the production, as a 1400-ft. string of 121/2-in. casing was hanging in the hole, a salt-water horizon drilled through at about 800 ft., was not cemented off, and 3000 ft. of 4-in. drill stem with rotary bit was in the hole. This well's potential capacity was never determined, but it made 7000 bbl. of 25" Bé. oil through the bit and Pin. drill stem, in one of its sporadic flows before sanding up, and thus proved itself capable of the largest potential production of any well on the Isthmus. The well showed salt water before caving and sanding up with the drill stem still in the hole, and will probably never be used for production. Wells Nos. 22 and 23, drilled nearby, have proved disappointments after making good showings of oil. In the spring of 1922, Ixhuatlan wells Nos. 28 and 29, deep tests supposedly on the flank of the known salt cores in that field, went into solid salt; No. 28 at 2250 ft. and No. 29 at 2400 ft. No. 28 was continued in the salt for 1000 ft. before operations were stopped. Later comple-

Jan 1, 1923

By Stirling Huntley

With the threatened falling off in production of the lighter oil pools of the Tampico embayment in Mexico, a general search of that country for oil-producing regions has resulted in renewed activity in the region of the Isthmus of Tehuantepec, one of the first districts exploited in Mexico. Since the drilling of the first well in the San Cristobal section by the Pearson interests in 1902, drilling has been continuous, except during 1917-1921, when practically all development was stopped by the revolutionary activity. Early in 1921, a drilling campaign was inaugurated for the purpose of testing out the known salt-dome poolfi on the flanks of the salt masses, rather than on their tops where previous tests had been located. On Dec. 7, 1921, the Aguila Co., with which are consolidated the Pearson interests and which has been the only company active in developing this region, unexpectedly drilled into a sand horizon at 3015 ft. with its Conception well No. 18. The hole was unable to handle the production, as a 1400-ft. string of 121/2-in. casing was hanging in the hole, a salt-water horizon drilled through at about 800 ft., was not cemented off, and 3000 ft. of 4-in. drill stem with rotary bit was in the hole. This well's potential capacity was never determined, but it made 7000 bbl. of 25" Bé. oil through the bit and Pin. drill stem, in one of its sporadic flows before sanding up, and thus proved itself capable of the largest potential production of any well on the Isthmus. The well showed salt water before caving and sanding up with the drill stem still in the hole, and will probably never be used for production. Wells Nos. 22 and 23, drilled nearby, have proved disappointments after making good showings of oil. In the spring of 1922, Ixhuatlan wells Nos. 28 and 29, deep tests supposedly on the flank of the known salt cores in that field, went into solid salt; No. 28 at 2250 ft. and No. 29 at 2400 ft. No. 28 was continued in the salt for 1000 ft. before operations were stopped. Later comple-

Jan 1, 1923

By Franklin G. Pardee

WARTIME depletion of the reserves of iron ore in the Lake Superior region of the grade and character now being shipped down the Lakes was serious. The time has come to take stock of the resources that remain in order to plan our future program of supply for our blast furnaces and protect, as far as possible. the tremendous investment made in the Lake Superior iron mining industry. Hugh M. Roberts and William H. Crago have estimated the reserves of the Lake Superior region in the United States at two billion long tons. These reserve figures are of direct-shipping ore and those concentrates produced by methods now in commercial use or those methods that may be expected in the near future. In their estimate they have assigned 392 million long tons to the Michigan ranges (all reserves in long tons) : 112 million tons for the Gogebic. 140 million tons for the Menominee, and 140 million tons for the Marquette.

Jan 1, 1948

By Eugene McAuliffe

IT is not possible to include in this paper, limited as it is in scope, the many diverse steps toward the reduction of mine accidents that are taken in the mines that produce the nation's coal. Every coal-producing state has enacted laws covering proper mining practices, and the major portion of these are directly related to the safety of the mine employees. The United States Bureau of Mines, the American Institute of Mining and Metallurgical Engineers, The American Mining Congress, a number of national, regional and state organizations, as well as the coal technical press, have covered time and time again all of the "do" and "don't" phases of mine operation that bear on the important question of mine and employee safety. Within the past 15 years The Union Pacific Coal Co. has attempted to put into practice in its mines in southern Wyoming these many good recommendations, finding some value in all, and yet, to secure substantial results, the management found it necessary to resort in the end to what might be referred to as "extra-territorial" methods. It is the writer's purpose to show in this paper that marked and even extraordinary betterment can be brought about when employer and employee work together with due sincerity. In presenting our own experi-ence, one that has been duplicated in so far as results are concerned on numerous other properties, no theory of perfection of management exists; on the other hand, our organization feels that as long as our record of accidents remains as shown by even our latest and best performance we still have far to go. Safety work in some form has been carried on in and about the mining properties of The Union Pacific Coal Co. since the first mine was opened at the now long-abandoned town of Carbon, Wyo., in 1868. On June 30, 1903, an explosion and subsequent mine fire occurred in mine No. 1 at Hanna, taking 169 lives, and a second explosion occurred in tile same mine on March 28, 1908, in which 59 additional lives were lost. Looking back with impartiality on the causes leading up to these two unfortunate disasters, we can only conclude that shooting from the solid, the absence of adequate ventilation, rock dusting, the use of water at the face to allay

Jan 1, 1938

By H. H. Reamer, B. H. Sage

The formation volume and the relative volume of the liquid Phase of mixtures of Condensate and gas from five different parts of a field in the Louisiana area have been established experimentally. These studies included gas-condensate ratios as high as 25.000 cu ft/bbl at pressures up to 5,000 psi. The gravities of the tank condensates were between 53.9° and 63.9° API. The compositions of the condensate and gas samples inves-ligated are presented in tabular form. The formation volume. the relative volume of the liquid phase. and the specific volume of the mixtures are available. A rough correlation of the formation volume as a function of pressure. temperature, and gas-condensate ratio has been presented. This correlation i-considered applicable only to the range of conditions covered in this investigation for systems of similar nature and com-position. INTRODUCTION Often a knowledge of the influence of temperature. Pres sure, and relative quantities of condensate and gas upon the volumetric behavior of fluid*. from a given field has been employed in estimating the Conditions existing in the reservoir. The early work of Beecher and Parkhurst' and the more rrcent Studies of the Dominguez' and San Joaqnin Valley Field;: are examples of experimental studies of this character. Correlation of the volumetric behavior of naturally occurring hydrocarbon mixtures has Proved To be feasible' . at low gas-conden-sate ratios-; for fluids*. from a single geographic area. Progres 5 is being made in the Prediction of the volumetric behavior of distillate systems at high gas-condensate ratios and pressure.. However. the estimation of the retrograde". ' dew-point pressure still remains uncertain and probably can best be established by experiment. For this reason it appears of interest to make available experimental information about the volumetric behavior of mixtures of condensate and gas from five different part.; of a single field. This material shows a rough similarity to data for mixtures of condensate and gas from San Joaqnin ' Valley Fields. In the present paper. 110 attempt has been made to coordinate the available information on tbe volumetric behavior of fluids from condensate fields. It appears hopeful that progress can be realized by the utilization of recently developed equa-tions of state.!' However. the primary problem in any such correlation is the proper identification of the components and constituents of naturally occuring systems. Additional experimental information may be required to permit the determination of the values of the constants of the equation of state for References given at end of paper. Manuscriptt received in the office of the Petroleum Branch June 11. 1951. *For present purposes low gas- condensate ratios will he considered as those below 3,000 cu ft/bbl, and the region of high gas-condensate ratio will be limited to compositions containing more than 5,000 cu ft of pas per bbl of condensate. Mixtures Containing between 3,000 and 5.000 CII ft OF gas per bbl will be considered of intermediate gas-condensate ratio.

Jan 1, 1952

By William R. Rumbold

WHEN I was in South Africa during the latter part of 1904, there were three known tin-fields, which may be called the Cape Town, the Bushveld and the Swaziland fields. THE. CAPE TOWN TIN-FIELD. This district is situated near Kuils river, 20 miles west of Cape Town, and 5 miles from Kuils River station on the Cape Town & Stellenbosch Railway. The deposits are in granite, intrusive in the Malmesbury beds, which are supposed to be of Silurian or Cambrian age. The granite, resisting denudation better than the surrounding shales,, has formed low-lying hills, the highest of which, the Bottlelary Berg, is 1,510 ft. above sea-level. , The rock consists of quartz, orthoclase feldspar and biotite mica; tourmaline is also present. The feldspar occurs in large crystals. The rock is generally decomposed on the surface, and the decomposition sometimes extends as deep as 100 ft. This formation-granite intrusive in Silurian shales-extends for many miles to the northeast, but so far as I know the Kuils River deposits are the only ones now known to occur in it, though probably further prospecting will reveal other deposits. This particular discovery was accidental;. alluvial tin being found in the course of boring for oil. The Kuils River Deposit. This comprises both lode and alluvial tin. The lode strikes N. and S., and dips about 30° E. into the hill. It is 5 ft. wide, and composed of dense white quartz, in which pinkish-gray cassiterite is distributed in large crystals. The vein also contains considerable quantities of wolfram. Fig. 1 is a rough plan of the relative positions of the lode and the alluvial deposit, the latter, as shown, following the course of a stream, while the lode crops out on the hillside

Jan 7, 1908