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By E. T. Clymer

It has been the custom, from the earliest time, to grade pig-iron by the appearance of the fracture; and although, since the pneumatic and open-hearth methods of steel-making have come into existence, chemistry has been called to the assistance of the steelmaker in selecting material for his use, the consumers of forge- and more especially of foundry-iron, still rely almost entirely, as they did a hundred years ago, on the appearance of the fracture of the pig to guide them in the choice of iron. To this rule, however, each year sees more exceptions; and there are now many foundry-men

Jan 1, 1893

By L. D. Jaffe, W. P. Clancy, D. C. Buffum

Many earlier workers have suggested that the temper brittleness of steel is associated with the presence of carbon or nitrogen. Nevertheless, no investigations on the effect of removal of these elements upon susceptibility to temper brittleness have been published. It was therefore decided to determine whether temper brittleness would develop in an iron alloy ...__, ing very little carbon and nitrogen. The alloy, in the form of a 10-lb ingot, was prepared by melting purified materials under . argon. Its composition, in per cent, was: This analysis, except for carbon content, is within the specified range for SAE 3140, which has been demonstrated by previous work at this laboratory2 to be markedly susceptible to

Jan 1, 1950

DAVID THOMAS 1871 R. W. RAYMOND 1872-1874 A. L. HOLLEY 1875 ABRAM S. HEWITT 1876 T. STERRY HUNT 1877 ECKLEY B. COXE 1878-1879 WILLIAM P. SHINN 1880 WILLIAM METCALF 1881 RICHARD P. ROTHWELL 1852 ROBERT W. HUNT 1883 JAMES C. BAYLES 1884-1855 ROBERT H. RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B. POTTER 1888 RICHARD PEARCE 1889 ABRAM S. HEWITT 1890 JOHN BIRKINBINE 1891-1892 H. D4. HOWE 1893 JOHN FRITZ 1894 J. D. WEEKS 1895 E. O. SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898

Jan 1, 1944

By H. A. Wilmeth

IN 1955, before planning an accelerated stripping program, Chino Mines Div. began an engineering study to improve data for estimating truck haulage costs for any future haulage layout. The study aimed to develop: 1) significant unit costs, 2) a method of estimating travel time from which truck needs and future stripping rate could be determined, and 3) yardsticks of performance to measure haulage efficiencies. It was suggested that to provide significant unit costs, expense accounts should offer management two types of cost control information-unit cost yardsticks with which monthly unit costs could be compared and unit costs for estimating future expenses for any haulage layout.

Jan 5, 1958

Florida State Geological Survey, Tallahassee, Fla Herman Gunter, State Geologist A list of publications will be sent upon request Citizens of the state may obtain publications available without cost, others may have them for postage, or they can be sent express collect Twenty Annual Reports have been issued from 1908 up to and including the 21st-22nd Annual Report (1931). Only three are now available; 4th Annual Report (1912), 15th (1924) and 18th (1927) Reports since 1921 contain statistics on mineral production. All reports contain papers on various subjects, many of which are still available separately, and are so indicated in the list of publications. Seven bulletins have also been issued, principally of interest to paleontologists Bulletin 7, The Pensacola terrace and associated beaches and bars in Florida (1931), is of more general interest Bulletins will be sent upon receipt of postage. Thirteen Press Bulletins, most of which are available, have also been issued, but are of minor interest

Jan 1, 1933

On October 20, 1964, in his Waldorf Towers suite, death came to Herbert Clark Hoover, 31st President of the United States. At his bedside were his two sons, Allan A. and Herbert Hoover, Jr. Many years of humanitarian and public service earned him the gratitude of millions here and abroad. The Nation mourned his death. For the mining fraternity and AIME in particular, the life of Herbert Hoover held particular meaning. During the years from 1895 to 1914 when he was actively engaged in mining, he conducted himself with extraordinary competence, energy and integrity. In the years following, when his qualities of administration and leadership literally forced him into the limelight, he continued his interest and lent his talents for the benefit of the engineering profession.

Jan 11, 1964

By B. Heide, A. Bergrnann

The Meggen mine and the concentrator plant of the Sachtleben Bergbau GmbH are located in the southern part of the Ruhr district of the Federal Republic of Germany. The mine has been in operation for more than 100 years, but the concentrator described in this paper was started up in January 1963. The Meggen orebody is of sedimentary origin and occurs in a zone of limestones, graywacke and shales of Devonian age. The average thickness of the deposit is 3 meters and due to an intense folding of the area, the mineralized zone dips steeply at 80º towards the north.

Jan 6, 1973

October Meeting of the Institute.-Invitations have been sent to the members of the following societies through the respective Secretaries to attend the October meeting of the Institute and the Dinner which will be given on the evening of Oct. 17 : American Society for Testing Materials, American Iron and Steel Institute, American Society of Mechanical Engineers, American Society. of Civil Engineers, American Institute of Electrical Engineers, . American Foundry men's Association. Members of these Societies have also been invited to contribute to the discussion of the various papers to be presented at the meeting, a revised list of which appears in the notes of the Iron and Steel Committee on p. vi. Many individuals of national and international prominence have also been invited to contribute discussions of these papers, and the response to these invitations has been extremely encouraging.

Jan 9, 1913

By T. W. Martin, T. J. Crocker, J. M. Goris

The current technology of large rock conveyors is reviewed. Based on this investigation two large rock conveyor concepts have been developed and a test facility investigation designed and fabricated. The USBM will test these concepts along with loading and transfer points for handling mine run rock material up to 1.5 m (4.9 ft) in size. An evaluation of open pit mining systems using large rock conveyors documents substantial cost savings when compared to truck haulage.

Jan 1, 1983

By H. E. Howe, A. A. Smith

E. Schumacher.*—Mr. Smith has shown us once again how variable lead alloys can be. I have studied lead alloys for a good many years and know from experience that their behavior cannot be predicted by analogy with other alloys. I have always been interested in observing how the creep resistance of lead may be improved by the addition of as little as 0.03 per cent Ca. Without the presence of calcium the grains of extruded lead pipe are fairly equiaxed and motion can take place easily at the boundaries. The calcium addition of 0.03 per cent causes the grain boundaries to become very irregular and jagged, and results in creep resistance many times greater than that of pure lead. Mr. Smith showed that in the one per cent antimony-lead alloy creep is occasionally excessive even where low stresses are involved. We have observed this phenomenon many

Jan 1, 1945

By J. E. Johnson

The description of the machine which coilstitutes the subject of this paper is best iutroduced by a statement of the conditions which led to its construction, which may be briefly given as follows : The ore handled at the plant to be here described* is of the variety sornetimes called by those familiar with the brown ores of the South, " Mountain," as distinguished from the " Lime-

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