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Human progress has a visible material phase, easily discernible, that is expressed in the standard of living. This material phase, however, is only the outward expression of a spiritual or mental phase that acts as a driving force in making humanity improve both its outlook and its mode of living. The instrument of progress is the human brain. Under the urge of spiritual drive, the brain acts as a focal point to utilize the forces of nature and put them to work for the benefit of mankind. Besides intelligence, which is an innate quality, the tools of the human brain are knowledge, experience, training, initiative, and skill. Given sufficient intelligence, the human brain can make an amazing amount of progress, provided it is supplied with an adequate spiritual and moral urge and a good technical background. It is the role of education to sup- ply such a background. The material phase of human progress proceeds on a series of parallel fronts, all of them interdependent to some extent (Fig. 7). The rise of the standard of living, dependent as it is upon the manufacture and mass distribution of goods, is based essentially upon the development and utilization of the material resources of a country or land area. This development involves the extraction of mineral and organic products from Mother Earth, their transportation to manufacturing centers, their transformation into finished goods and their dis-

Jan 1, 1950

By J. E. Burke

THE origin of recrystallization textures continues to be a matter of controversy. One explanation is that a recrystallization texture occurs because only grains having a limited range of orientations ever appear in the deformed matrix—the oriented nuclea-tion* hypothesis. Another explanation is that grains essentially having all orientations are nucleated but that those having certain orientations grow much more rapidly than any others in the deformation texture, and thus only the rapidly growing grains survive when recrystallization is complete. There has recently appeared a great deal of evidence'- indicate that recrystallized grains of face-centered cubic metals are frequently related to their parent grains by rotations of 20" to 40" about a common [lll] direction. Furthermore, it has been observed that the growth rate of the new grains depends upon their orientations with respect to the matrix, and that the most rapidly growing grains lie within the stated range of orientations. In a recent note, Beck7 has concluded from observations of this type that oriented growth alone is responsible for the appearance of preferred orientations in re-crystallized metals. It should be pointed out. however, that many of the available data indicate that oriented nucleation operates in addition to oriented growth. Thus, while oriented growth may permit a selection to be made among nuclei of several orientations, only a limited number of orientations are available in the first place for such selection.

Jan 1, 1953

By H. Shaw

It is now generally recognized that the gravitational method of geophysical surveying is a valuable aid in elucidating the geological structure of the subsoil and enables the practical geologist to deduce the presence of useful deposits. The particular suitability of the torsion balance to the location of large and important subterranean structures has given rise to a wide application of this method by many of the important oil companies in their search for future supplies, and so intense have been these efforts that little has been heard of the method in other connections, with the exception of occasional references to its application in the location of hidden deposits of metallic ores, salt and lignite, and a number of accounts of its use in the elucidation of geological structures. Its success in the location of salt domes is well known, and establishes it as one of the most important of the geophysical methods, especially for the indirect location of oil. In the British Isles, however, no large occurrence of oil is likely to be revealed, and here the practical application of the gravitational method has been restricted almost entirely to the search for ores. This type of survey possesses well marked characteristics, and presents a gravitational problem that has necessitated the development of a special and probably unusual plan of campaign, full details of which it is hoped will shortly be published. The problems and difficulties encountered in this work are of necessity fundamentally related to those met with in the search for oil by means of the torsion balance, but they also possess several special and distinctive features which undoubtedly differentiate them from the obstacles confronting the oil prospector, and which call for special consideration and treatment. In certain of the various oil-producing areas of the world, and particularly in the Gulf Coast region, the geology may be regarded as comparatively simple, while the oil is usually associated with a large and well defined structure such as a salt dome or anticline, which is capable of giving gravitational indications sufficiently extensive to be detected by the torsion balance over a fairly wide area of the ground surface. It is customary, therefore, during the preliminary survey of an area for oil, to

Jan 1, 1929

By W. W. Mason

The US began exporting coal in the late 1800s, at first in very small quantities to Canada and, beginning in 1897 and 1898, to the east coast of South America. Shipments to European countries began on a very limited basis in 1902 and these shipments increased gradually until World War I when shipments overseas increased from 7.3 Mt/a to 20 Mt/a. After the war exports dropped as fast as they had increased and, with the exception of exports to Canada, remained at very low levels until just after World War II when the US again emerged as a major coal exporter. World War II left the coal industries of Europe in ruin. As the US was the only country able to supply large quantities of coal at reasonable prices needed for reconstruction of the European economy, the US coal exports overseas expanded rapidly to 38.6 Mt in 1947. Additionally, we shipped 23.8 Mt of coal to Canada in that year for a total export of 62.3 Mt. Unfortunately, that level was not reached again until 1957 when exports reached an all-time high of 69.3 Mt - a high that has not been reached since. Over the years the level of US coal exports has fluctuated fairly widely. Approximately 80-90% of all US coal exports are high quality metallurgical grade coal so our exports level depends directly on world-wide economic conditions and world steel production levels.

Jan 1, 1982

By E. W. Engelmann

A NEW and interesting type of drier has been developed and operated at the Magna plant of the Utah Copper Co. for the past year for the drying of a filtered concentrate in the molybdenum recovery plant of this company. The several units installed have ranged from 12 to 30 in. in width, and from 14 to 30 ft. long. Their economy was immediately apparent after the first one was installed. The machine is not only low in capital cost, but has proved efficient for the drying of fine concentrate at low operating cost. The Utah vibrating drier consists of a steel conveyor trough supported on flexible reeds from a structural steel foundation anchored in concrete. The steel pan, which is also the drying surface, is vibrated by a heavy Utah electromagnetic vibrator fastened either to the head or discharge end of the pan. The vibration thus obtained agitates the material and causes it to be conveyed over the heated surface.

Jan 1, 1938

By Myron Rodgers

IN rock- or ore-crushing tests all data, in order to be valuable for study and comparison, should be obtained and tabulated under conditions as uniform as possible. The results of many such tests have no value for comparison, because of incomplete data and the lack of uniform conditions, screens and scale of sizing, etc. The purpose of this paper is to suggest a form of standard specifications which may be developed by the Milling Committee and approved by the A. I. M. E. for rock-crushing tests. It is not intended to discuss any theories of rock crushing. Reports of rock-crushing tests should include the following details: 1. Description of the machine employed (jaw or gyratory crushers, rolls, stamps, tube mills, Chilean mills, etc.). 2. Method and material (timber, concrete, etc.) of foundation. Much power is dissipated in the vibration of poor foundations. 3. Locality from which the rock or ore was obtained, and geological, mineralogical, and physical characters of the material. 4. The power consumption of the machine running with no load and with full load, the unit of power being 1 hp, per 24 hr. 5. The capacity of the machine in tons (of 2000 lb.) per 24 hr. 6. The duty in tons per horsepower-day. 7. The screen analysis of feed and product by the proposed A. I. M. E. standard screen scale. On the foregoing statement, the following remarks are offered.

Jan 9, 1915

By M. Bourgon

The conductivity of liquid copper sulfide has been measured as a function of the mole fraction of sulfur in the melt at three temperatures: 1170°, 1250°, and 1300°C. The results show that a) the conductivity of copper-rich Cu,S is independent of the sulfur pressure in the furnace, and b) the conductivity of sulfur-rich copper sulfide increases rapidly with sulfur pressure. Assuming that the band theory is applicable to liquids leads to the conclusion that copper-rich copper sulfide is an intrinsic semiconductor, in which case electrons act as carriers. The activation energy for conduction in this case has been calculated to be 0.7 ev. On the other hand, sulfur-rich copper sulfide behaves as a p-type semiconductor, positive holes being responsible for conduction. IN order to elucidate the structure of Liquid copper (1) sulfide, Derge, Pound, and Osuchl have studied the electrical conductivity of this compound as a function of temperature. Their results showed that the conductivity is rather high, of the order of 100 ohm" cm", and that the temperature coefficient of conductivity is positive. This high conductivity seemed to indicate electronic rather than ionic conduction. This conclusion was checked further by Derge, Pound, and Yang,2 who measured the current efficiencies of copper sulfide melts at various temperatures. In all cases, the current efficiency was found to be nil, indicating the absence of appreciable ionic contribution to the conduction in

Jan 1, 1958

By F. M. Lewis, Johnson. E. C.

BY now application of the liquid-solid cyclone to various classification problems in the chemical and metallurgical fields is more or less familiar. A less publicized application receiving wider consideration as time goes on is its use as a classifier in closed-circuit grinding operations. This paper presents the costs involved and the experience gained from operating a unit of this kind. In May 1951 the Tennessee Copper Co. installed in its London mill at Copperhill, Tenn., a liquid- solid cyclone in closed circuit with a 6x12-ft ball mill. The circuit in which this cyclone is used is the regrind or secondary grinding circuit of a copper flotation plant. Originally it consisted of a 7x1-ft conical ball mill in closed circuit with a bowl classifier. Changes made in the primary grinding circuit of the mill necessitated a regrind circuit of greater capacity. The bulk concentrate to be ground was raised from 900 or 1000 tpd to 1200 or 1300 tpd, and to accommodate this increase a 6x12-ft ball mill which had been in the primary grinding circuit was moved into the regrind circuit. When this was done it was found that the classifier was too small to give efficient operation. Space in the plant was at a premium, and since use of the cyclone offered considerable economy the installation shown in Figs. 1-3 was made.

Jan 6, 1954

By Robert T. Hill

PHYSIOGRAPHICALLY, Mexico provinces, which are, in a manner, distinct economic areas. These may be denominated, (1) the Gulf coastal plain; (2) the Cordilleran plateau; (3) the Sonoran, and (4) the Tehuantepecan province. Fig. 1 shows the approximate boundaries of these provinces. The first is the continuation of the coastal plain of Texas and the Gulf region in general, which, except for prospective oil and lignite, has little of interest for the mining engineer.

Jan 1, 1902

By Frank Firmstone

In 1871, two furnaces at the Glendon Iron Works, which had been blown out on account of the "coal strike," were altered from the open-top plan with side flues for collecting the gas, to closed tops with cup and cone. In one furnace the suppression of the side flues permitted a considerable alteration in the profile, but in the other (No. 5) no change in this respect was made; the side flues were simply bricked up and new ones cut through the sides close to the top. This furnace was in blast over four years, and we can, therefore, form a pretty good idea of the effect of the alterations on the furnace process. The principal dimensions are; Height 72'; greatest diameter, 18'; diameter at tuyeres, 8'; diameter of top, 10'; diameter at stock line (point at which the top of the materials is kept), 11'; cubic contents, 11,900 cubic feet. The table below shows the average results for periods of twentysix weeks each. 1st, of the open-topped furnace; 2d, of the furnace with the first charger used, which was an ordinary cup and cone (diameter of cone 5' 2") 3d, with the charger used ever since, a " double " cone 7' 5" diameter outside, having a central opening 3' in diameter. The diagram (Plate 11) shows the daily variations, in the grade of the irons for the same periods.*

DESPITE strikes, domestic production of copper and zinc in 1951 rose about 3 pct and 10 pct, respectively. Lead output fell only about 7 pct. Primary refined, including processed scrap and imported concentrates, was somewhat higher for zinc, and slightly lower for copper and lead. Prospects are for moderately larger mine and refined production in 1952 according to Standard & Poor's analysis of nonferrous metals. The survey goes on to report domestic copper prices averaged 14 pct higher in 1951, lead prices 30 pct higher, and zinc prices 32 pct higher. The 2¢ rise in zinc and lead ceilings in October will lift the average price in 1952 over 8 pet, assuming no further price change. Currently, OPS appears opposed to raising the 24 ½ ¢ copper ceiling to the 24 ½ ¢ maximum on imported metal. The steep premiums in world markets are likely to be reduced in 1952. Sales in 1951 were at new peaks. A further moderate rise is indicated for 1952. Earnings of the industry were at a new high in 1951. The increase for companies covered in the survey was perhaps 25 pet, despite a tax rate of about 53 pet, against about 40 pct. in 1950. Relatively maintained to moderately higher earnings are currently indicated for 1952. About two thirds of the companies covered in the survey raised dividends, including extras, in 1951. In general, maintained payments appear probable in 1952.

Jan 1, 1952

By Alexander N. Mitinsky

Up to a certain limit, the increase of pressure on the diamond-drill increases the rate of progress in drilling. That limit is set by the resistance of the diamonds to compression; and beyond it, the destruction of the stones will involve an economic loss, both in time and in money. It is, therefore, important to all diamond-drillers to know what is the resistance mentioned. In Europe, operators usually follow an empirical rule, which directs the maintenance of a pressure, on the area of the bottom of the drilling-tool, of 12 kg. per sq. em. For the tools in ordinary use, this is equivalent to 1 kg. per sq. mm. of the diamonds set in the tool. So far as I know, American drillers are using pressures as high as 50 to 60 kg. per sq. em. of the total area of the drill, and the consumption of diamonds (on Denny's authority, 0.2 carat per meter bored) is greater in America than in Europe. But the reason for this diffrence may be the comparatively larger size of the diamonds commonly used by American drillers. With the assistance of my friend, the late S. Woisslaw, who was the pioneer of diamond-drilling in Russia, I selected from his stock a number of black diamonds, which I subjected in my laboratory to compression-tests, To prepare regular cubes for such tests, as is generally done with other stones, would have been not only costly, but, what is more important, practically useless. I therefore determined, in order to assimilate as nearly as possible the conditions of actual use, to place each sample between a hard plate (corresponding to the rock) and a softer plate (corresponding to the bottom of the tool), into which it would be pressed during the test.

Jan 1, 1907

By Nicholas T. Camicia

Coal is one of our oldest known commodities. Historic evidence indicates that this fossil-formed fuel was used in China and in Wales some 3000 to 4000 pears ago. Coal was discovered in North America in 1679 by French explorers in northern Illinois, and in 1700 a colony of Huguenots came across bituminous coal in Virginia. One might think by this long history of a single commodity that the string was about played out. Quite the contrary, coal is in greater demand than ever before and coal mining today is a modern industry. It is in an unprecedented growth period as the nation-and the world-demands more and more energy coincident with dwindling reserves of other fossil fuels. By the year 2000 the demand for coal is expected to at least double the current level of some 600 million tons annually despite the advent of nuclear power. To meet this challenge, the coal industry is vitally in need of an increasing supply of technically trained and progressive manpower. And, coupled with a serious shortage of engineers and technicians, it represents a rich vein of occupation opportunities-all the way up to top career levels. Today, coal mining is a complex, highly specialized industry concerned with more than just getting coal from the earth and putting it into the furnaces of the consumer. The industry is concerned with the environment, with maintaining a viable ecology. Recognizing the ramifications of global economics, the industry is very much aware of its important position in contributing to a constantly rising standard of living throughout the world. The key to rewarding employment in the coal industry is skill-skill that has been developed by education, training, and experience. None of these alone is enough; all three are necessary today to produce the skill needed to meet the employment requirements of the coal industry. Routine manual labor will no longer do the job in coal mining. In the United States coal mining has been mechanized to a degree unsurpassed anywhere else in the world, and the coal worker must be thoroughly

Jan 1, 1973

By W. M. Small

Austria.—Austria produced some 430 cisterns of 10,000 kg. each of crude oil of a 0.9428 sp. gr. during 1934. Gosting II well near Zis-tersdorf was placed on the pump in August and at the end of the year was still producing about three cisterns daily. This well is owned by the Erdöl-Produktionsgesellschaft while Gösting I is owned by Raky-Danubia. Only five wells were completed in the republic during the year. These accounted for 1783.5 meters of the 2225 meters drilled. The only producer completed was Gosting 11. At the close of the year, four rigs were in operation and one rigging up. At least 8 or 10 new wells are planned in Lower Austria for 1935. The European Gas & Electric Co. put its 6-km. gas line into operation in May and has sold 12,301,550 cu. m. of gas to the Vienna City Electric Works. A 2-km. pipe line was built from Gösting II to the railway loading rack near Zistersdorf. Hungary.—No oil or gas was produced except a small amount of gas trapped from flowing artesian wells. The Government completed and abandoned a 1500-m. hole at Tisztaberek in northeastern Hungary and is drilling at 967 m. near Bogáes, 120 km. northeast of Budapest. It is unofficially reported it plans to drill two new wells in 1935. The European Gas & Electric Co. has a rig up for a test at Mihalyi in Transdanubia. Czechoslovakia.—In Gbely (Egbell) there were produced 1283 cisterns of 10,000 kg. of 0.935 sp. gr. oil and a small amount of gas used for fuel. This field is operated by the Government; 17 shallow producing wells and three dry holes were drilled, with a total of 3351 m. of hole completed. In Hodonin (Goding) there were produced approximately 1300 cisterns of 10,000 kg. each of 0.91 sp. gr. oil and a small amount of gas used for fuel. The field is operated by the Apollo, which drilled four producing wells averaging 460 m. in depth, one small gas well of 550 m., one small gas well 260, and one dry hole 230 m. Two wells were deepened a total of 80 meters. The Government is drilling below 800 m. in a wildcat test in eastern Czechoslovakia near the Rumanian frontier.

Jan 1, 1935

CHARLES KIRCHHOFF, Chairman. ALBERT SAUVEUR, Vice-Chairman. HERBERT M. BOYLSTON, Secretary, Abbot Bldg., Cambridge, Mass. John Birkinbine, J. Esrey Johnson, Jr., Felix A. Vogel, William H. Blauvelt, William Kelly, Leonard Waldo, James Gayley, . Richard Moldenke, William R. Walker, Henry D. Hibbard, Joseph W. Richards, - William R. Webster. Henry 1%1. Howe, E. Gybbon Spilsbury, Frederick W. Wood. Robert W. Hunt, A. A. Stevenson, The Board of Directors of the Institute has authorized the holding of a meeting under the auspices of the Iron and, Steel Committee in New York City, October 16 and 17, 1913. Gratifying responses have been received to the request of the Committee for contributions, the following papers being already assured: 1. H. M. Howe, Equilibrium Temperature for A, in Carbon Steel. 2. H. M. Howe, The Divorcing of the Eutectoid in Meteorites. 3. H. M. Howe and A. G. Levy, Determination Of the Position of Ae3, in Carbon-Iron Alloys. 4. G. .K Burgess, J. J. Crowe and H. S. Rawdon, Thermal and Microscopical Examination of Professor Howe's Standard Commercial Steels. 5. H. Dl. Hove, Discussion of the Existing Data as to the Position of Ae3,. 6. J. H. Hall, Shock Tests of Cast Steel. 7. H. F. Miller, Jr., The Design of Regenerators for Open-Hearth Furnaces. 8. E. Stütz, Paper on the "Scoria Process." 9. Albert Sauveur, Mayari Steel. 10. Felix A. Vogel, Briquetting. 11. J. E. Johnson, Jr., Paper on " Cast Iron."

Jan 6, 1913

By James Fisher

THE copper mines of the Keweenaw Peninsula in northern Michigan have long been of interest in connection with deep earth-temperature measurements. The extraordinary low geothermal gradient of 1° F. in 223.7 ft. announced by Agassiz1 as a result of measurements dating from 1886, although later" stated as in error, served to focus attention on this region as one offering, because of the great depth of the mines, unusual opportunity along this line. Lane,3 Van Orstrand4 and others have made valuable contributions to this study. Fresh opportunities afforded by the constant deepening of the mines, improvements in the accuracy and reliability of temperature-measuring instruments together with increasing knowledge of the heat conductivities and specific heats of the rocks, led the Michigan College of Mining and Technology in cooperation with some of the mining companies to renew work on this problem. It is planned eventually to complete a survey which will make use of the favorable opportunities for deep rock-tempera-ture measurements presented in these mines. This survey should include the determination of a depth-temperature gradient in both conglomerate and amygdaloid mines, and also the variations in temperature at the same depth in different geological formations. The first problem has a direct bearing on the question of providing equipment for necessary ventilation with increased depth. The second may show that a relation exists between the natural rock temperature and the mineral content of the formation.

Jan 1, 1932

"The largest variety of asphalt and related bitumen deposits in this country is found in Utah. Utah is one of the few places in the world where the hydrocarbon minerals, gilsonite or uintaite, wurtzilite (trade name elaterite) and ozokerite are produced. These bitumens occur in an area embracing nearly 10,000 square miles in eastern Utah near the Colorado line. This area is largely in the western part of the Uintah basin. The bitumens are in the Tertiary horizon in the various divisions of the Eocene series.Gilsonite is an asphaltite derived from petroleum, wurtzilite is an asphaltic pyrobitu¬men derived from petroleum, and ozokerite is a native mineral wax resulting from the met-amorphosis of paraffinaceous petroleum.Gilsonite is produced by the Gilson Asphaltum Company, a subsidiary of the Bar¬ber Asphalt Company, at Watson, Utah. A narrow guage railroad, seventy miles in length and with a 7 1/2 percent grade over the Book Cliffs on Baxter Pass, was constructed by the company from the Denver & Rio Grande Western railroad main line in order to open up the gilsonite deposits. The veins range from narrow upward to 18 feet in width. The Rainbow vein at the present wokings is eight feet wide, vertical, and has sandstone walls. This vein has been opened up for a distance of about three miles and in some places four hundred feet deep. Forty men usually are employed with a production of eighty tons per day."

Jan 1, 1925

By F. C. Blake

The best method for the estimation of copper in ores and secondary products is that proposed by Dr. Steinbeck* for the award offered by the Mansfeld'schen Ober-Berg-und Hutten-Direction. It is based upon the decolorization of the blue ammonia solution of copper by potassic cyanide.7 It is necessary for the accurate estimation of copper in arsenides that the arsenic be separated from the copper before the ammonia solution is made. The presence of a notable amount of arsenic renders the titration by potassic cyanide inaccurate, the end reaction being obscured by the appearance of a yellowish-green tint towards the end of the titration. The change of the color of the ammonia solution from blue to the tint caused by the presence of arsenic cannot be used for an end reaction, for the intensity and quick appearance of the latter color depend upon the amount of arsenic present in the solution. In the analysis of speise, the method of separating the copper by an oxidizing and reducing treatment in the muffle, to volatilize the arsenic, gives poor results, and there may easily be some loss of the weighed sample. The separation of the precipitated sulphides of arsenic and copper by treating with sodic sulphide, gives good results, but the process is tedious. I have used the two following methods, which are simpler and more expeditious than those mentioned, with good results

Jan 1, 1881

By G. Barbery

Since the original paper, two methods have been introduced to compute the parameters of the three parameter size distribution equation: [ ] Both of them are based on graphical means, which are time-consuming and of little statistical significance. A program has been developed, using the Gauss-Newton method to compute by nonlinear regression analysis the parameters of the equation. Although the method is quite general in curve-fitting applications, it does not appear to be used in the field of size analysis, and a brief description is given. As applied here, the Gauss-Newton method involves the minimization of the least squares: [ ] where n is the number of sieves used. The second member of Eq. 2 can be approximated by a multiple Taylor's series expansion of first order about a starting value [ ] The minimization of Q (r,s,Xo) means: [ ] Putting Eq. 3 into Eq. 2 and differentiating, we obtain a system of equations which can be represented in matrix symbolism (box) The system can be solved for: [ ] and the operations repeated with new values: [ ] The starting values for r and s are taken as 1, for Xo, a value higher than the maximum sieve opening value. Applied to the data given by Herbst 5,6 for batch grinding of 7 X 9 mesh dolomite, the parameters given in Table 1 were obtained. The discussion of the significance of the residual sum of squares is a difficult subject in multiple nonlinear

Jan 1, 1972

By C. G. Dunn, J. L. Walter

COULOMB' and Coulomb and Lacombe2,3 have recently discussed secondary recrystallization in soft iron (99.5 pct Fe). They found that the appearance of this phenomenon was dependent on both the presence of impurities and the thickness of sheet specimens. They concluded that impurities such as carbon, sulfur, and oxygen in the soft iron stabilized the matrix structure and allowed growth of a few grains of specific orientations. They also found that secondary recrystallization ceased when the final thickness was small and attributed this complete inhibition of growth in thin sheet to the restraining action of thermal grooves. When purer iron (99.99 pct Fe) was used, normal grain growth but not secondary recrystallization was obtained. On the other hand it is known that the necessary stabilization of the matrix structure for secondary recrystallization in high-purity silicon iron probably does not depend on impurities but more likely results from the specimen thickness effect of Beck et al.,4 according to evidence and ideas advanced by Walter and Dunn,5,6 and Detert.7 Furthermore, Mullins8 has indicated that if a gas-metal surface energy difference exists across a grain boundary equal to or greater than about 3 pct of the grain boundary energy, then such a grain boundary should not become stuck. Similarly, Walter and Dunn have estimated that any increase in restraining force due to increased thermal grooving with decrease in

Jan 1, 1962