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By D. H. Baldwin, R. E. Reed-Hill

WITH the polarized-light microscope, the basal-plane trace may be located on hcp crystal surfaces to an accuracy of approximately 1 deg. This determination can also be made on very small crystalline areas, approaching a micron in width. Measured basal-plane trace distributions on selected specimen surfaces can yield1,2 valuable texture information. However, the polarized-light microscope is probably best suited to orienting

Jan 1, 1965

IRON AND STEEL COMMITTEE ALBERT SAUVEUR, Chairman A. A. STEVENSON, Vice-Chairman HERBERT M. BOYLSTON, Secretary, Abbot Bldg., Cambridge,- Mass. Guilliaem Aertsen, Robert W. Hunt, E. Gybbon Spilsbury, John Birkinbine, J. E. Johnson, Jr., J. S. Unger, William H. Blauvelt, Charles Kirchhoff, Felix A. Vogel, Charles A. Buck, Richard Moldenke, Leonard Waldo, F. D. Carney, Charles F. Rand, William R. Walker, James Gayley, Joseph W. Richards, William R. Webster, Henry D. Hibbard, . C. F. W. Rys, . Frederick W. Wood. Henry M. Howe, Messrs. Guilliaem Aertsen, C. A. Buck, and F. D. Carney have accepted membership on the Committee.

Jan 3, 1914

By O. P. Hood

None of the methods now in use for the transportation of materials underground is entirely free from more or less serious objection.

Jan 1, 1915

By P. A. Witherspoon, Y. W. Tsang

Normal stress-fracture closure variation and stress-dependent fluid flow rates were calculated for rock fractures of different aperture distributions. This study shows that both the mechanical and hydraulic properties of the fracture are controlled by the large-scale roughness of the rock fracture. Hence the typical large-scale undulation wavelength of the rock joint dictates the suitable sample size to be used in normal stress and fluid-flow measurements, if results due purely to sample size are to be avoided.

Jan 1, 1982

By Charles Barron McIntosh

BECAUSE of the well known relationship between a low atmospheric pressure and increased amounts of methane in coal mines, attempts have been made to find associations between low pressures and coal mine explosions. An early study by F. Able disclaimed this relationship. He found that half the explosions took place during a rising barometer when methane content in a ventilated mine would be decreasing. A more recent study by C. L. Hosler revealed a close relationship between anthracite mine explosions and low atmospheric pressure. Bituminous coal mine explosions, where coal dust as well as methane can be exploded, were found to be more closely associated with a rising pressure following a low barometer than with the falling or low pressure period.

Jan 10, 1957

US 4,185,872-In the solution mining of uranium values from a subterranean uranium ore deposit, a lixiviant comprising sodium sulfate or other alkali metal sulfate and optionally minor proportions of an alkali metal carbonate or bicarbonate and an alkali metal hypochlorite is introduced into the ore to solubilize uranium therein. The pregnant lixiviant is recovered for processing. E.T. Habib, Jr., assigned to Mobil Oil Corp. Jan. 29, 1980. 5 pp (299-4). Filed- 8-18-78 (934,933).

Jan 1, 1982

By Hayes Theiling Dorton

This paper describes the record-keeping and reporting responsibilities of the West Virginia Department of Mines and tells about the pilot project conducted to demonstrate the feasibility and worth of implementing a computer-based formation management system encompassing the large amount of data used by the Department and to lay the groundwork for future implementation of a state-wide information network. The paper briefly discusses the equipment and software that was used. It also discusses the system data files and subfiles that were constructed (or will be constructed in later phases of the project). Finally, the paper describes how the system will expand in the next several years.

Jan 1, 1983

By Kirby D. Mellegard, Ralph A. Wagner, Paul E. Senseny

Six creep laws for salt, each fitted to the same laboratory data base, are used in a numerical model of the deformation of an opening in salt to determine the influence of creep law form on the predicted closures. Results show that predicted closures can be very sensitive to the functional form of the creep law chosen to model the laboratory data.

Jan 1, 1982

By R. E. Stewart

The major mining companies of the world all face the problems associated with investing in new mining ventures. In particular, investment in foreign countries - whether these are advanced or developing countries - requires careful consideration. A thorough analysis of all the possible risks must be undertaken, so that realistic decisions can be made. Some of the points to be considered are outlined in this paper.

Jan 1, 1977

By Edgar G. Tuttle

The accompanying figures show the arrangement of a twocompartment excentric jig fitted with adjustable and automatic discharges for drawing oft' the lower product obtained in jigging minerals, ores, coal, etc., which is designed to remove or separate more effectively the materials treated, as they travel over the jig from the receiving- to the discharge-points.

Jan 1, 1897

By E. J. Schmitz

The existence of copper-ores in the Permian measures of Texas has long been known, and these ores have been, from time to time, the object of geological researches and mining

Jan 1, 1897

By P. Schwed

IN determining the mechanism responsible for sintering, the most direct procedure available is the comparison of the observed time and temperature dependence of the process with the dependence to be expected upon the basis of each conceivable mechanism. This was done by Kuczynskil who, in treating the mechanism of surface diffusion, postulated, in effect, that the concentration gradient of vacancies is different from zero only within the neck. This procedure was recently questioned by Cabrera' who assumed, on the contrary, that diffusion occurs only in the region outside the neck. In the present note, the calculations are performed without restriction on the region of diffusion. To carry out this objective it is first necessary to

Jan 1, 1952

Efficient energy utilization in the electrolytic zinc process, relative to other zinc processes, is one of the reasons for its wide adoption in recent years, says John D. Siddle, zinc plant superintendent at the Bunker Hill Co., Kellogg, Idaho. Designers and operators of electrolytic zinc plants have pioneered process improvements, new equipment, and operating techniques to conserve energy. As energy costs increase it the future and competitive pressure mounts against less-efficient producers, these energy-saving improvements will he regarded as necessary for economic survival. Plant designers and operators should not lose sight of the savings in operating costs possible through intelligent utilization of all available forms of energy.

Jan 11, 1977

By K. H. Nimerick, B. E. Scott, F. J. Beafore

A unique freeze conditioning agent (FCA) which functions by forming structurally weak ice rather than suppressing the freezing point of water has been successful in alleviating frozen coal problems. Frozen coal treated with FCA has been quickly unloaded at temperatures below -17.8°C (O°F). Other applications of FCA include deicing: conveyor belts, idler, idler arms, and other moving parts that have been impeded by ice.

Jan 9, 1979

POSITIONS VACANT No. 255. A company manufacturing malleable iron fittings in Connecticut needs a manager for its steel department. Experience with converter is essential. No. 256. A prominent mining company in Central America wishes a shift boss for its mill and cyanide plant, who is technically trained, experienced, and can speak Spanish. He should he sufficiently expert to be able to take entire charge of the mill in case of emergency. Salary $150 per month on a two years' contract, with additional allowance for board, lodging and transportation expenses. No. 257. A Mexican copper mining company in the State of Puebla needs an engineer on surveying and mapping and drafting in connection with field construction. Healthy locality. Salary $150 per month.

Jan 1, 1918

By R. K. Dunham, A. N. Styler

The results of two studies into the effects of undermining offshore room and pillar workings by longwall faces are presented. The first study indicated no potential instability from undermining one level of room and pillar workings. On the basis of this it was decided to undermine two levels of room and pillar workings, again monitoring pillar stability. The results showed no signs of increased instability.

Jan 1, 1982

By Akira Yokoyama

Japan is composed of four main islands: Honshu, Hokkaido, Kyushu, and Shikoku (Fig. 1). Between Honshu and Kyushu, a railway tunnel and a road tunnel have been open since 1942 and 1958, respectively. Hokkaido, [ ]

Jan 1, 1970

Jan 1, 1915

By E. C. Reed

Drilling operations in Nebraska during 1943 were reduced to approximately two thirds of the 1942 number. Twenty-seven wells were completed during 1943 and five wells were drilling at the close of the year. Eight of the completions, in provcn fields, were producers. The operations were distributed throughout the state as follows: eleven in Richardson County, four each in Buffalo and Harlan Counties, three in Furnas County, and single operations in Antelope, Butler, Dakota, Dawes, Gage, Nemaha, Otoe, Pawnee, Scotts Bluff and Sherman Counties. Thc principal feature of exploration drilling in the state during the year was the more extensive testing in the central Nebraska Basin region, principally in Buffalo and Harlan Counties, where

Jan 1, 1944

Jan 1, 1925