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By L. E. PORTNER

INCREASING military demands on the petroleum industry have brought into bold relief the crude-oil reserves now available to meet combined military and civilian demands, emphasizing the necessity for a greater efficiency in recovery from what has been discovered than ever before, particularly in light of the absence of new discoveries. This situation-and the fact that the industry, as well as members of the Government charged with governing oil production, desire to meet all crude-oil demands made of the industry with the least loss in tangible reserves through production practices-paves the way for increasing application of sound principles of production engineering and conservation.

Jan 1, 1944

By M. Cohen, C. Wagner, J. E. Reynolds

If the total volume of a diffusion couple changes during the diffusion, the measurement of distance becomes ambiguous. Use of distance parameters as suggested by Hartley and Crank is discussed. For small concentration differences, the standard form of Fick's second law is retained with conventional length units and the in- terdiffusion coefficient D. It is shown how D can be calculated from experiments involving large concentration differences and analyzed in terms of distance parameters. 'The merits of incremental diffusion couples involving small concentration differences are emphasized. THE conventional form of Fick's second law for one-dimensional diffusion of component B in a binary solution of A and B is where c, is the concentration of component B; x, the distance; t, the time; and D, the interdiffusion coefficient which may depend on ca. Hartley and Crank' have pointed out that Eq. 1 applies only if the total volume of the diffusion couple does not change during the diffusion process; otherwise, the definition of x becomes ambiguous. No change in total volume takes place if the specific volume of the solution is a linear function of the weight fraction Wb, or if the molar volume is a linear function of the mol fraction N. In some alloys, however, these relationships do not hold, and then it is necessary to introduce a modified measure of distance, 4 in order to retain the general form of Eq. 1. The application of Hartley and Crank's suggestions to diffusion in alloys has been discussed by Wagner.' Relation Between Measure of Distance and Units of Concentration The definition of [ depends on the choice of units for the concentration c,, as follows: 1—If the concentration ca is measured as the weight fraction W, (or weight percent), [ = 5, has to be defined so that equal increments of contain equal increments of mass m of the solution, e.g., dm = pSdx = Sdw [2] where p is the local density of the solution, and S is the cross-sectional area in sq cm which is taken to be constant in this problem of one-dimensional diffusion." * da Silva and Mehla have demonstrated the constancy of the cross-sectional area in the usual type of diffusion couple. However, experiments involving diffusion into thin wires4, 5 may exhibit changes in cross-sectional area, and therefore are excluded from the present treatment. Thus and the unit of is gram per sq cm instead of cm. 2—If the concentration c, is the mol fraction N, must be defined so that equal increments of contain equal numbers of mols of solution, e.g., dn= (S/V)dx= Sd [41 where V is the local molar volume of the solution. Thus dt, = dx/V [51 and the unit of is mols per sq cm. 3—If, as may be advisable in the case of interstitial solutions, the concentration C is measured in terms of the molar ratio of components B and A (c,, = Y, = nH/nA, where n and nl are numbers of mols of B and A), = Y has to be defined so that equal increments of contain equal numbers of mols of A, e.g., dnA= (NAS/V)dx = Sdf [6]

Jan 1, 1954

By Oscar A. Glaeser

INDUSTRIAL relations in the United States Smelting Refining and Mining Company's Western operations covers the field of personnel and labor relations, and the principal aims are to render service to the employes of the Company and to its operating departments. Accident prevention Safety is a primary function. A safety engineer is employed at each operation. The wholehearted support of Company officials, staff, and the working force has been most successful in preventing accidents. Constant vigilance has been combined with a policy of building safety into all operating activities whether these are in the construction of a new facility, the developmnt of a mining system, or the direction of the working force. That this policy has produced results is attested to by the fact that the accident frequency rate at the Company's major mining operations in Utah has been reduced approximately 75 per cent in the ten-year period ending Dec. 31. 1946.

Jan 1, 1948

By E. J. Roberts

Prior to 1916, thickening was an art, and any accurate decision as to what size of machine to install to handle a given tonnage of a specific ore must have been one of those intuitive conclusions, based on both intimate and extensive acquaintance with thickners and ore pulps. Then in 1916 "knowledge of acquaintance," became "knowledge about" with the publication of the Coe and Clevenger paper.' The unit operation of thickening had graduated to the status of an engineering science. The fundamental similitude relationships for the two major phases of the operation were defined so clearly that batch tests on models as small as liter cylinders could serve to specify protypes as large as 325 ft in diameter.

Jan 1, 1949

By S. A. Falconer

Much attention and publicity has been given, during recent years, to grinding, classification, flotation, and thickening. The various technical papers, and symposiums held to discuss these important phases of milling, have contributed to a better under- standing of the fundamental principles and operating variables involved. Another important part of milling- to the flotation operator-is a treatment step to which frequently too little attention is given-" conditioning," or the treatment the ground mineral pulp receives before it enters the flotation machines. Conditioning" is a hackneyed and frequently misused term, commonly employed to describe the pretreatment of surfaces of minerals in ore pulps or mill pr6ducts prior to froth flotation. In general, such pretreatment is for the purpose of changing the flotation characteristics of these mineral surfaces to enable them to respond in some desired predetermined manner when subjected to flotation. Taggartl states that the function of conditioning is "either to insure selective collector coating of one mineral species while another species is not; or to take such steps as will compensate for departure there from."

Jan 1, 1949

By AIME AIME

THE climax of the various programs and entertainments in connection with the holding of the World Engineering Congress* in Tokyo in October was the complimentary dinner given by the visiting members of the Institute to our members in Japan. At the same time President Bradley conferred an honorary membership on Baron Takuma Dan, the vice-president of the World Engineering Congress.

Jan 1, 1930

By Nathan C. Rockwood

BASIC mineral commodities may be divided into two general classifications in their market or price characteristics. In one class are commodities sold on a world-wide basis, as gold, silver, nickel, asbestos and petroleum, and in the second are those produced and sold locally. Of course, no precise line of demarcation exists between the two; coal, for instance, belongs more or less in both. If there are enough producers of any commodity to prevent control of production by any one person or group, a free market then exists and the price in a buyer's market is determined by the most favored producer-meaning the producer, with the lowest production cost or the lowest cost of transportation, or both, to the particular market, or place of use. With minerals in the first classification, their high intrinsic value far outweighs the transportation cost and a uniform market price is accepted as an essential element in the economy of distribution. But with common minerals of small. intrinsic value and relatively high transportation costs, economists are reluctant to admit that a uniform price may also be an essential element in distribution.

Jan 1, 1940

By Stewart, J. B.

THE property at which this work was done consists of a large deposit of potash salts occurring in massive beds of rock salt, overlain by 600 ft. of salt-impregnated shales and marls. It is in the Province of Cataluiia, Spain, about 45 miles from the railway station of Mauresa and about a mile south of Suria. In addition to sinking the shaft, the program of construction work laid out by the European owners (not Spaniards) included a single-track narrow-gage railroad from Mauresa to the mine; one large office building and several large shop buildings, all of brick and concrete with steel truss roofs; two extensive benches for the future recovery plant; and a large village of stone dwellings for employees. The pay-roll showed approximately 1200 to 1500 men employed. After two years' operation, ending early in the autumn of 1920, the shaft had been sunk 325 ft. and still had an equal distance to go to reach the potash; all tunnels for the railroad were done and the road-bed $0 per cent completed; only a little more than the foundations were completed for all the large buildings, and the excavations of the benches were about 75 per cent done-while only a fair start had been made upon the employees' village. This was the state of affairs when the European owners decided to offer this property under a one-year option to an American syndicate, providing that they agreed to carry on the entire building program and to sink the shaft as fast as was consistent with the quality of work which they demanded, for they wished the shaft to endure at least 200 years.

Jan 1, 1926

By H. F. Beardmore

PETROLEUM consumption during 1946 broke all previous records and further increases are expected during 1947. U. S. consumption amounted to an average of 5,280,000 bbl a day, of which 4,745,000 bbl was domestic crude oil, with the rest from natural gasoline production and crude oil imports. World consumption during the past year, excluding Russia, is estimated at 7,200,000 bbl daily. Forecasts for 1947 indicate a U. S. consumption of 5,425,000 bbl daily of petroleum products. This is expected to be made up of 4,655,000 bbl of domestic crude oil production, 340,000 bbl of natural gasoline production, 400,000 bbl of crude oil imports, and the rest from stocks. Petroleum's principal use is still as a fuel. The field remains highly competitive, but petroleum has been continuously progressing. Less than fifty years ago, oil supplied only one twentieth as much of the nation's total energy as coal, but today it supplies over half as much.

Jan 1, 1947

By Marcus Nadler

WAGES in the United States, in spite of the wage freeze, have increased materially. Overtime payments have become standard practice in almost all industries. Now efforts are being made to place wages on an annual basis, and if this is adopted, it will result in an increase in the cost of production. Organized labor today is more powerful than ever before; union membership is large and steadily increasing, and in many instances membership in the union is a prerequisite to employment. The treasuries of many unions are strong as a result of the large membership and full employment. The unions, therefore, today are in a much better position than ever before to carry on long strikes. Politically, too, the unions are more powerful today than they ever were. On the basis of their strength, one may expect that some of the demands that the labor unions will make in the not distant future will be granted. It is, therefore, quite evident that before long, particularly when the curtailment in war production reaches about 40 per cent, this country will be confronted with a serious labor problem.

Jan 1, 1945

By Howard N. Eavenson

DURING the past year, as in the preceding ones, prices continued to fall, production to decrease, and more mines were closed. Much attention is being given by the industry to suggested plans for betterment of its position, and if the scheme recently brought out for consolidation of sales agencies into district agencies is loyally carried out, it cannot but help to improve conditions. The progress in the anthracite industry is shown in the report of its chairman, E. H. Suender; changes in coal preparation are outlined in the report of J. B. Morrow, chairman of Committee on Coal Preparation, while increased mechanization of the western mines is described by Eugene McAuliffe, chairman of the Committee on Machine and Strip Mining. In spite of the depression, interest in the Coal Division has been increasing, its meetings have been well attended, and its committees are active and have been doing excellent work.

Jan 1, 1932

By Irwin H. Cornell

BRIEFLY stated, the history of the St. Joseph Lead Co. is the story of how a group of men, working for ten years as officers without salaries and stockholders without dividends, developed a small mine in Missouri into what became a large and prosperous corporation. Their courage and faith in the scattered surface deposits of lead coupled with the management's engineering vision and sound financial judgment should prove an inspiration to present-day mining operators and investors. In 1717, John Law's company, known as "The Company of the West," was formed in France and letters patent were granted, for a period of 25 years by Louis XV, for exploration in the Mississippi River Valley. One of the underlying purposes of the expedition, headed by Mr. Renault and Mr. La Motte, a French metallurgist, was development of the lead mines in the area now known as Southeast Missouri.

Jan 1, 1947

By AIME AIME

BY the end of 1943, the United States will be able to produce aluminum at a rate of 1,150,000 tons a year. How much aluminum is 1,150,000 tons? It is sufficient to replace every railroad passenger car in this country three times a year. Or, it would put a thirty-piece aluminum cooking utensil set in every one of America's 34,000,000 homes with enough metal left over to make 5,000,000 miles of aluminum transmission cable, such as was used in the electrification of much of rural America. Expansion of aluminum production capacity for the war program has occurred in three steps: (1) expansion by private industry; (2) the letting of contracts by the Defense Plant Corp. for the construction of additional aluminum plants which may remain after the war to compete with existing facilities; and (3) the more recently announced D.P.C. program for the building of emergency plants to make aluminum, using stand-by power available in large metropolitan centers power of relatively higher cost, making it questionable whether such plants, now gravely needed, will be able to compete in a peacetime economy.

Jan 1, 1943

By Colin G. ink

OUTSTANDI'NG in progress among the less familiar 'metals during 1936 is the electrolytic production of 99.9 per cent manganese meta1 readily and many quantity. Strictly speaking, manganese should not' be classed as 'a rare metal, since there is 800 times as much manganese in the earth's crust as there is zinc or lead. But manganese' as a metal is rare, just as titanium metal is rare though titanium is five times as abundant in the earth's crust as manganese.

Jan 1, 1937

By James K. Richardson

Today, the enigma of the "missing man" in the metal mining industry equals, and frequently surpasses in objective importance, the problems of ore development, drilling, sampling, pumping, milling techniques, geophysical prospecting, or any one of a hundred highly technical subjects. Unfortunately, as engineers, we have confined our attentions, in the main, to the scientific phases of mineral technology, relegating our man power problems to the background. But what good has all our scientific study and preparation been if we can't get the ore mined, milled, or smelted? What has happened to our labor supply? Where is the good old miner who could timber, drill a round, lay track, or do any job underground?

Jan 1, 1949

By Clyde E. Williams

IN planning a postwar program for manufactured products, it is essential that the bases for the plans be wisely chosen. First we must make certain assumptions as to the war's ending. Let us assume: (1) complete victory by the United Nations, (2) peace terms that will ensure the direction of the economy of all nations of the world toward peaceful pursuits, and (3) an early ending of the war, that is, before the nations of the world, excluding the enemy, are near the point of physical and spiritual exhaustion. Thus, our manufacturing plants and transportation facilities will still be in good shape. The plants and transportation facilities, as well as the cities of a large part of Europe, however, will be badly crippled. The rich mineral and other raw material resources of the world, little of which was under control. of the Axis powers before the war or will be after the war, will not be used up. Control of these raw materials, or at least an important part of them, will remain in the hands of the strong peaceful nations.

Jan 1, 1943

By Earle C. Waite

THE Industrial Minerals Division this year held no individual sessions of its own except the business meeting Tuesday afternoon. One session was held jointly with the Society of Economic Geologists, one with the Milling Methods Committee, and two with the Society of Economic Geologists and the Mining Geology Committee. At all of these meetings the attendance was better than usual and the Tuesday afternoon session, with nearly 400 present, probably set a new record for the Division. Joint sessions seem extremely popular when papers of mutual interest are presented. On Monday afternoon, mica was the predominating subject. The North Carolina mines provided most of the information presented, although the discussion brought out similarities with the New England mines. B. C. Burgess particularly stressed the fact that with the existing curtailment of mica from India it is necessary to get the most mica in the shortest time from the mines in this country. He said that the Colonial Mica Corp. hopes to have 1000 mines operating in the near future. This seems a great number, but when one considers that these mines employ from 3 to 28 men, mostly nearer the low figure, the output of each mine is relatively small. Although the price of mica is from six to ten times the prewar price, the yield of 8 to 150 lb. of mica per ton of raw ore does not provide high returns to the producer.

Jan 1, 1943

By D. W. Loucks

There is plenty of evidence to indicate that at least one of man's chief interests in life is to make himself as comfortable as possible. If you doubt this, just watch the fellow next to you for the next half hour trying to find the most comfortable position that a hard chair has to offer. Comfort, however, does not always mean an easy chair. To some, it may mean a wealth of money: to another, freedom from worry. But to most of us, it means first of all a comfortable atmosphere in which to live, and to a great many of us it probably also means freedom from that annoying task of firing the furnace. Today more than ever before, automatic heat is one improvement that is placed high on everyone's list. Perhaps this is because automatic heating is becoming relatively cheaper. Perhaps it is because of a good publicity campaign on the part of the oil and gas men or maybe it is just that we are getting lazier day by day. At any rate, almost every issue of Better Homes and Gardens, House Beautiful, or your other favorite home magazine carries an article extolling the virtues of this or that automatic heating system.

Jan 1, 1949

By J. F. K. Brown, E. E. Roecker

For three years The Hudson Coal Co. has used egg anthracite instead of coke in its foundry cupola. It has long passed the stage of being told it cannot be done—the metal would be cold, of poor quality, or the speed of operation would be low. From observation, from use and from test. we know that our metal is about average; the cast iron invokes no adverse comment from the machine shop and the speed suits our foundry requirements. We have there-iore resolved into practice anthracite combustion processes in an industrial furnace formerly using coke, under conditions suitable to our needs. When it comes to translating what we know into use in another cupola, however, where operating conditions may be different, or to explaining why, with seemingly the same conditions in our own cupola, we have attained sometimes a temperature of 2800° in the metal and at another time 2600°, or a speed of 5 tons per hour against 2 35 tons per hour, we cannot do it. We cannot do this because there seems to be an unbridged gap between laboratory ideas on combustion and practical ideas on com-bustiqn, which we have been unable to cross in terms understandable to us as practical consumers. This gap or bridge centers around the problem of how combustion actually takes place; and we believe it is controlled by two factors: (I) the character of the surface of the fuel and (2) the space provided and needed within which the oxygen of the air is allowed to or can act on that surface. It has long been contended on behalf of coke that porosity is an important factor in combustion, although, admittedly, there are two schools of opposing thought on this question, as revealed in technical literature. It has been understood generally that a light, porous coke is the best metallurgical fuel because there are more square inches of carbon exposed to the blast of air, therefore more useful carbon-dioxide reactions can take place in the given space between the entrance of the air and the point where useful work is done. It is now our general idea that the heavier and the harder the coal, the better the metallurgical fuel, provided the surface of that fuel is suitable for fast reaction with the oxygen. Time and Space A cupola is loaded in layers of fuel and iron. The horizontal line where the first charge of iron rests on the coal is the top of the bed coal. With us that is 22 in., usually, above the tuyeres where the air enters. This means 600 lb. of coal. Every subsequent coal layer is 100 to 125 lb. of coal, and that 100 to 125 lb. of coal melts 1000 lb. of iron at around 2700° in the ladle. This quantity of coal represents a 3-in. layer spread across the cupola. The question arises: If this 3 in. of coal will melt 1000 lb. of metal, why was it necessary to use 600 lb., or 22 in., of coal beneath and between the first charge of iron and the air entrance?

Jan 1, 1944

By E. E. Roecker, J. F. K. Brown

For three years The Hudson Coal Co. has used egg anthracite instead of coke in its foundry cupola. It has long passed the stage of being told it cannot be done—the metal would be cold, of poor quality, or the speed of operation would be low. From observation, from use and from test. we know that our metal is about average; the cast iron invokes no adverse comment from the machine shop and the speed suits our foundry requirements. We have there-iore resolved into practice anthracite combustion processes in an industrial furnace formerly using coke, under conditions suitable to our needs. When it comes to translating what we know into use in another cupola, however, where operating conditions may be different, or to explaining why, with seemingly the same conditions in our own cupola, we have attained sometimes a temperature of 2800° in the metal and at another time 2600°, or a speed of 5 tons per hour against 2 35 tons per hour, we cannot do it. We cannot do this because there seems to be an unbridged gap between laboratory ideas on combustion and practical ideas on com-bustiqn, which we have been unable to cross in terms understandable to us as practical consumers. This gap or bridge centers around the problem of how combustion actually takes place; and we believe it is controlled by two factors: (I) the character of the surface of the fuel and (2) the space provided and needed within which the oxygen of the air is allowed to or can act on that surface. It has long been contended on behalf of coke that porosity is an important factor in combustion, although, admittedly, there are two schools of opposing thought on this question, as revealed in technical literature. It has been understood generally that a light, porous coke is the best metallurgical fuel because there are more square inches of carbon exposed to the blast of air, therefore more useful carbon-dioxide reactions can take place in the given space between the entrance of the air and the point where useful work is done. It is now our general idea that the heavier and the harder the coal, the better the metallurgical fuel, provided the surface of that fuel is suitable for fast reaction with the oxygen. Time and Space A cupola is loaded in layers of fuel and iron. The horizontal line where the first charge of iron rests on the coal is the top of the bed coal. With us that is 22 in., usually, above the tuyeres where the air enters. This means 600 lb. of coal. Every subsequent coal layer is 100 to 125 lb. of coal, and that 100 to 125 lb. of coal melts 1000 lb. of iron at around 2700° in the ladle. This quantity of coal represents a 3-in. layer spread across the cupola. The question arises: If this 3 in. of coal will melt 1000 lb. of metal, why was it necessary to use 600 lb., or 22 in., of coal beneath and between the first charge of iron and the air entrance?

Jan 1, 1944