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By Cyril Wells, Robert F. Mehl

The two earlier papers in this series1,2 presented data on the rate of diffusion of carbon and of manganese in gamma iron. Apart from their scientific interest, these data are needed chiefly in order to treat data on carburization, on rate of formation of pearlite, and on rate of austenit-izing in a quantitative way.1'2'9'10 In the present investigation rates of diffusion of nickel in ?-Fe over wide temperature and concentration ranges have been determined, and the effects of carbon, of im- purities, and of grain size on these rates have been studied. Claussen,3 using the data of Fry,4 has calculated the diffusion coefficient of nickel in y-Fe as 9.2 X 10-11 sq. cm. per sec. at 1200ºC., but had no data from which to calculate the variation of D with concentration, temperature, and percentage of carbon. Method and Materials Method.—Nickel was diffused along the axis of a cylindrical specimen across a concentration gradient, concentration-penetration curves were determined and D values calculated from Grube or Matano solutions.5 Details of the method are given

Jan 1, 1941

By Eckley B. Coxe

I WISH to call the attention of the Institute to a peculiar variety of anthracite which occurs in the Buck Mountain vein at our collieries at Drifton, and in the same and other veins in different localities in the anthracite coal-fields. It is known among the workmen as iron-gray or cast-iron. It has a dull, greasy appearance, as if a piece of ordinary anthracite had been rubbed with a dirty and greasy rag and allowed to dry. It was formerly considered a very impure coal containing a high percentage of ash, and was picked out of the coal and thrown away. But the following analysis of it and of its ash, made by Mr. J. Blodget Britton, of Philadelphia, shows that such is not the case, the percentage of ash not being much higher than that of the ordinary anthracites as they are prepared for market.

Jan 1, 1879

By William E. Ford, Edward Salisbury Dana

506. Scope of Descriptive Mineralogy. - It is the province of Descriptive Mineralogy to describe each mineral species, as regards: (1) form and structure; (2) physical characters; (3) chemical composition including blowpipe and chemical tests; (4) occurrence in nature with reference to geo- graphical distribution and association with other species; also in connection with the above to show how it may be distinguished from other species. Further, it should classify mineral species into more or less comprehensive groups according to those characters regarded as most essential. Other points which may or may not be included are the investigation of the methods of origin of minerals; the changes that they undergo in nature and the results of such alteration; also the methods by which the same compounds may be made in the laboratory; finally, the uses of minerals as ores, for ornament and in the arts.

Jan 1, 1922

By Herbert Lang

Cord-wood, sawn into blocks of about a foot in length, is a regular constituent of our fuel-charge at Mineral, Idaho, our work being the matting of silver-ores by fusion in a blast-furnace. The furnace is a round water-jacket furnace, of 36 inches diameter at the tuyeres, and the charge of smelting-mixture weighs 950 Ibs., requiring 110 Ibs. of Connellsville coke to drive it. I replace half this coke with 135 lbs. of fir-wood, cut from dead and apparently perfectly dry trees. This mixtrire produces as high a sn~elting-temperature as all coke, whence I infer that the smel ting-effeot of a given weight of wood is to that of the same weight of coke as 11 to 27, or 1 to 25/11. A cord of wood sawed ready for use weighs 2840 lbs., costs $5.00, and is

Jan 1, 1892

SHORTLY after Ambrose Swasey suggested the creation of the Engineering Foundation in 1914, the World War broke. upon the scene. Consequently all eyes were soon turned to national security problems. In 1916 the newly-organized Engineering Foundation and the four National Societies joined with the National Academy of Sciences in establishing the National Research Council. From then until 1923 the Engineering Foundation devoted the greater part of its resources to the support of the Research Council and the Council's division of engineering. Since 1923, how-ever, it has turned to the original intention for which it was created, of cooperating with the national societies in proj-ects affecting engineering at large, though it still retains a connection with the Research Council. Mere enumeration and tabulation of work undertaken can of course lend but a vague idea of actual accomplish-ments. The reports of the Foundation give information of its widespread activities.

Jan 2, 1928

By J. E. Pogue

That the domestic consumption of gasoline displays a marked seasonal variation, with a low in the winter and a high in the summer, is well known. It is logical to expect that the nature of the variation has itself been undergoing a change as a result of improvement in roads, general employment of closed cars, and growth of mass haulage; but so far as I am aware the change in seasonal variation has never been investigated and measured. It is the purpose of this paper to present the method and results of such an investigation, undertaken as a contribution to the technique of planning operating schedules now so prominent in connection with the functioning of the industry under a Federal quota system. For the method employed I am indebted to the suggestions and help of Frederick R. Macaulay,1 who kindly looked over the work sheets; and

Jan 1, 1934

By K. J. Anusavice, R. T. DeHoff, H. Oikawa, J. J. Pinajian

STUDIES of nickel self-diffusion and impurity diffusion in pure metals and alloys have, for the past two decades, employed predominantly the nickel radio-However, because of the low energy of the emitted particle, careful and time-consuming techniques must be used to obtain reproducible measurements. In our studies of nickel diffusion into copper, we have recently used Ni66 [Td1/2: 55 hr; : 0.20 Mev (100 pet)] which decays to it much more suitable as a tracer because of the presence of the high-energy y radiation from the cu66 daughter. Although the half-life of Ni66 is appreciably shorter than that of Ni63, the useful working lifetime of a small quantity, " 10 mc, is about 1 month. preparation bf Ni66. he Nis6 radioisotope was produced at Oak Ridge National Laboratory by means of a double (n,y) reaction:

Jan 1, 1969

PERSONAL (Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who registered at Institute headquarters during the period June 10 to July 10: J. C. Ralston, Spokane, Wash. E. P. Ashmore, So. Porcupine, Ont., Can. William H. Yeandle, Jr., Mexico City, Stuart Croasdale, Denver, Colo. Mexico. W. E. Hopper, Houghton, Mich. W. C. Minsch, Mexico City, Mexico. D. W. Brunton, Denver, Colo. H. V. Winchell, Minneapolis, Minn. Fred Crabtree, Pittsburg, Pa. W. G. Swart, Denver, Colo. Robert S. Lewis, Salt Lake City, Utah. D. F. Schindler, Madison, Wis. Noel Cunningham, Timmins, Ont., Can E. R. Pettebone has just been elected a Trustee of the Pennsylvania State College, being supported by the votes of the delegates of the Pennsylvania Anthracite Local Section of the Institute and the Engineers' Society of Northeastern Pennsylvania.

Jan 8, 1914

By R. L. Tobie

Handling and storing ore at transfer points underground are encountered frequently. An ideal solution to these troubles is probably still to be found, but at the Mather mine "B" shaft a method incorporating scraping trenches has been developed giving better service, from the standpoint of safety and simplicity, than obtained from other schemes. When shaft pockets are used for storage, the size of the ground opening required to assure capacity is often prohibitive, and shaft depth below the last level can become excessive, particularly if a crushing station is used. Also, if the material being handled contains large amounts of wet fines, it is difficult, if not impossible, to hold the material with regular chute gates. In order to remedy these problems Cleveland-Cliffs' Mather "B" has utilized three types of trenches. Types I and I1 are now in service and the third is under construction.

Jan 4, 1955

By Michael Richings

Although the role of slope stability has not changed, there have been changes in the mining industry which affect the geotechnician engaged in slope stability studies. The deposits currently being mined or evaluated are technically difficult , capital intensive, and economically marginal. In addition, many mining companies are now either controlled by oil companies or are financing projects through bank loans. The mining investor or decision maker is, therefore, often more sophisticated financially, but less sophisticated in mining terms. The impact of these changes will be to force the geo- technician and mining engineer to attempt to quantify risk and financial implications of a slope design. In conclusion, this paper outlines several questions which mining engineers should be asking those engaged in geotechnical studies and indicates the necessity for the mining engineer and geotechnician to work together and quantify the financial risk associated with a geotechnical design.

Jan 1, 1983

R. B. T. KILIANI, Denver, Colo. (written discussion *).-Mr. Len-nox's paper is decidedly interesting in that he shows that a field exists for the Chilean mill, in which its efficiency compares favorably with that of more modern grinding devices. The figures he has given clearly indi-cate that a coarse feed is conducive to higher efficiency than the fine feeds which the Chilean mill has usually been called upon to grind. The fact is also apparently indicated that operating the Chilean mill in closed circuit with a mechanical classifier results in still higher efficiency, and that in such cases the percentage of returns should be kept below 100 per cent. to obtain best results. It would be interesting to see the results of further tests with what Mr. Lennox calls "Mixed Feed," since the data given in Table 4 seems to' point to the fact that a mixed feed,

Jan 12, 1919

By Mason J. Christner

Geology has become increasingly quantitative in the last 20 years. This trend has been accelerated by computer capability in the manipulation of data. The mining industry has been relatively slow to harness computer power, but the larger companies have moved in this direction in the past few years. Among the leaders in this progression is the White Pine Copper Co., and the following is a brief description of their computer system for processing, managing, and utilizing geologic data. Geology The White Pine mine is in the Upper Peninsula of Michigan, 6 miles south of Lake Superior and 80 miles west of the Houghton-Hancock area, center of the famous Copper country. The ore body of chalcocite, native copper, and minor native silver, is a tabular body in the basal 25 ft of the flat lying Nonsuch Shale and the top part of the underlying Copper Harbor Conglomerate. Twelve or more

Jan 1, 1972

By William H. Mount

St. Joe Minerals Corp. has a long operating history of utilizing rubber-tired, trackless mining equipment in its Southeast Missouri Lead Belt underground mines. The company's first completely trackless mine, Hayden Creek, was opened in 1952, employing rubber-tired drill jumbos, electric shuttle cars, and articulated diesel trucks. The trucks were comprised of a conventional scraper tractor unit matched with a rear-dump rock wagon. These machines featured the first true earthmover tires to be used underground by St. Joe. The articulated truck concept proved to be very successful, and constitutes an increasing portion of the underground haulage today. St. Joe's second completely trackless mine, the Indian Creek property, was opened in 1954; conventional 9.1-t (10-st) rear dumps were used for haulage. Main haul roads were designed to be wide and fairly level to accommodate speeds of 32-40 km/h (20-25 mph).

Jan 4, 1976

By D. R. George

Preliminary research has identified several organic and aqueous solutions that are effective absorbents for SO, from simulated smelter gas containing 0.3 to 2% SO2. These SO2 loaded solutions are also compatible to the reaction of H2S and SO2 to precipitate a readily filtered elemental sulfur. The economic removal of SO2 and production of elemental sulfur from stack gases discharged by base- metal smelters is a challenging goal. The magnitude of this task is illustrated by the estimate that about 3.5 million tons of SO2 are discharged to the atmosphere by smelters annually in the U.S. The SO2 concentration of the gases ranges from about 0.5 to more than 3%. As the sulfur content of SO2 is 50% a potential production of 1,750,000 tons of sulfur per year is indicated.

Jan 1, 1970

The following list of corrections has been compiled from the thirty-five volumes, with some additions: VOLUME I. Page 160. The first two sentences of the second paragraph should read as follows : " For No. II we find that 2.33 percent. A1,08 take 4.07 per cent. 8109, leaving 3.48 per cent. 8102 free, which requires 3.25 per cent. CaO." Page 160, line 14, 3.79 should be 3.25; and in the 15th and 18th lines, 48.44 should be 46.98. VOLUME VI. Page 59. The discharges of the miners' inch per second, given as .2624 and .2499 cubic feet, should be .02624 and .02499, respectively. The discharges per minute, hour, etc., are correctly given. VOLUME VIII. Page 214. 16th and 25th lines, ferric carbonate should be ferrous carbonate. Page 486, 16th line, 10,000 should be 5,000. [ ]

Jan 1, 1907

By Gilbert P. Moore

Production in the Argentine in 1930 amounted to 1,415,099.7 metric tons, which converted into barrels of 42 gal., using the factor of 6.29, amounts to 8,909,773 bbl. This is a decrease of 481,613 bbl. from the 1929 production, which was 9,391,386 bbl. The production for 1930 was divided among three fields, as shown in Table 1. Table 2 covers Table 1.—Argentine Oil Production, 1930, by Fields Barrels Comodoro Rivadauia District Government........................................... 4,547,670 Railways Co........................................... 1,314,358 Astra-Eastern......................................... 1,016,024 Anglo-Persian......................................... 365,021 Solano Co............................................. 24,613 Dutch Shell........................................... 6,963 7,274,649 Neuquen District Government........................................... 569,245 Standard Oil-Argentina................................. 659,551 Astra-Eastern......................................... 8,234 Challaco Co. (Sol)...................................... 121,598 1,358,628 Salta District Government........................................... 90,576 Standard Oil-Argentina.................................. 185,920 276,496 8,909,773

Jan 1, 1931

By Hugh Archbald

IT is possible to construct a simple diagram of the earnings, or the production, of the men employed at a coal mine that will show not only if the conditions tend toward contentment among the men, but if the operating distribution of the work is correct. As earnings are the greatest cause of discontent, even exceeding all the other causes, if contentment exists in the matter of earnings, the likelihood of other discontents flaring up is greatly lessened. The basis of such a diagram would be the Gaussian curve of the normal variation in human ability. Such a curve has long been recog-nized. H. L. Moore,1 in discussing the quantitative relation between wages and ability says: "It has been pointed out that industrial efficiency is dependent upon physical, mental, and moral qualities, and these qualities . . . there is good reason for regarding as being distributed according to the Gaussian law..

Jan 7, 1924

More than 400 members and guests registered for the 146th General Meeting of the Institute held in Mexico City Nov. 9 to 15, inclusive. Of these, 250 came by special train or automobile from 24 states of the Union, and the others were resident in Mexico. Mexican Government officials, headed by Manuel Santillan, Sub- secretary of the Department of National Economy, acting in. behalf of the President of the Republic, and including the Secretary of Foreign Relations and the Governor of the Federal District, were most hospitable in their official welcome and provided splendid entertainment of various kinds. A reception was tendered by Hon. Josephus Daniels at the U. S. Embassy. Among other hosts were officials of a number of large operating companies, including M. H. Kuryla, of the Real del Monte company; Jules Lacaud, of the CompaiLia Minera de Chontalpan; and Harry Wright, of the Consolidated Steel company.

Jan 1, 1937

By I. N. Zavarine

THE observations presented in this paper were recorded during a study of the spheroidizing process. Spheroidization of cementite in steel is either brought about to develop a set of desirable mechanical properties or is an incidental result of mechanical and heat-treating manipulations. Physical properties of steel are materially influenced by the state of the cementite. Conversion of cementite from the lamellar to the spheroidal state is usually accom-panied by a decrease of hardness and of strength and by an increase in ductility. The spheroidized structure is usually considered as an ultimate step in the process of the softening of steel. The unorthodox hardening of a 3.5 per cent Ni steel (SAE No. 2330) after a heat-treatment that previously proved entirely suitable for a complete spheroidization of cementite in carbon steels led to the observa-tions that constitute the subject of the present paper.

Jan 1, 1939

By Henry U. Ross

The behaviour during reduction of iron-ore pellets and sinters was investigated. Several methods for the preparation of agglomerates and their reduction were tried. Commercial agglomerates from world-wide sources as well as experimental samples were tested. The effect of coke additions to pellet and sinter plant feeds was given special consideration. An analysis of the test results has helped to explain many of the phenomena associated with the reduction of iron-ore agglomerates such as swelling, loss in strength and wear resistance, changes in porosity, changes in mineralogy and the formation of metallic iron and slag. A double-layer pellet with all of the coke concentrated in the core proved particularly interesting. Although large quantities of coke showed that partially reduced agglomerates containing metallic iron could be produced in the laboratory, the problem of producing reduced pellets and sinters by the existing agglomerating processes still remains.

Jan 1, 1977