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By John F. Abel

AIME is closing the books on its first 100 years. In the next year the meetings and many papers will doubtless be filled with statistics on the growth of AIME, and, incidentally, on the mining industry. Let's try to keep our cool and avoid breaking our arms patting ourselves on the back. AIME, nationally and locally, runs on the drive and dynamism of a rather small number of its members. If you look at the annual SME Blue Book of national officers and committee members, you will be struck by the repetition of the same names throughout. Trend for a few men to shoulder the burdens and responsibilities can be seen on the local level, too.

Jan 1, 1970

There's a right way and a wrong way to store diesel electric systems and similar equipment for generating on-site power, according to James Frankow, service manager for Allis-Chalmers Corp's Engine Division. In any event, the less storage the better. Many generating sets are stored before installation, especially when new construction is underway. Improper storage, or mothballing, can create initial reliability problems. Therefore; arrange for inside storage with no drastic extremes in temperature or humidity. If engines and alternators are stored in areas other than inside a dirt-free and temperature-controlled building, the unit or engine should be completely covered and protected against the environment. Before covering it with a canvas or with plastic, the unit should first be sealed at the following critical engine openings:

Jan 3, 1978

By Willard S. Morse

The ores of the district are treated at this mill by the lixiviation process, consisting of drying, crushing, chloridizing-roasting and lixiviation by hyposulphite and Russell solutions. Gas is used as fuel for both drying and roasting, The gas-plant consists of two- Taylor revolving-bottom gas-producers, one 6 feet in diameter for the ore-dryers, the other 7 feet in diameter for the Stetefeldt furnace. The producers were made by Messrs. R. D. Wood & Co., Philadelphia, who also furnished the

Jan 1, 1893

By D. S. Choi, D. L. McCain

A method of estimating the chain pillar size required to support the wide working faces of longwall or shortwall coal mining is presented. The pillar size is determined through the use of coal strength, entry geometry, panel width, and overburden pressure. Design analysis is focused on a three-entry development system in the Pittsburgh Seam but can be used for other development plans and other seams by substitution of the proper geometric and strength data.

Jan 1, 1981

By S. H. Chauvenet

THE binding of the boshes and in walls of blast furnaces has always been an expensive piece of work. When the old stone stack was replaced by the iron shell, the brickwork was kept at a thickness of five feet or more. These five-foot walls were still too thick, and the practice now is to have as thin walls as possible and to have a free circulation of air about the brickwork of the furnace. The "basket," or lattice-work binding, accomplishes this object, but it is expensive, as to first cost, and, if any change in the diameter of a furnace has to be made, it necessitates an alteration of the binding or of the thickness of the walls.

Jan 1, 1882

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 R. A. Wyman

KYANITE schists in the Sudbury area have been generally described by Haw,1 who has also given particular information on preliminary treatment of three large samples from Dryden township, Ontario.2 Kyanite, garnet, biotite, quartz, and feldspar comprise the main ingredients of this ore. Kyanite is the valuable mineral. About 5 ½ tons of -35 +200 mesh product, made by dry rod milling, screening, and separation on the Exolon magnetic separator, were available for treatment by flotation. Magnetic separation had effectively reduced garnet and biotite so that flotation feed consisted essentially of kyanite, quartz, and feldspar, the kyanite content averaging 32 pct and representing about 86 pct of the kyanite in the original ore.

Jan 1, 1958

By W. J. Taylor

The discussion on my paper entitled "Experiments with a Straight or No-bosh Furnace," read at the Philadelphia Meeting, September, 1884 (Transactions, vol. xiii., p. 489), suggests the propriety of slipplementing it with another, giving my views as to the cause of the failure, which was so decided as to create surprise among furnace men. As then stated, the Chester (8. J.) furnace, which had been 60 feet high, and 13 feet in diameter at the bosh, was altered to an 8-foot bosh, with a 7-foot hearth, 7-foot stock-line, and 4-foot bell,

Jan 1, 1886

By H. Conrad, K. Janowski, E. Stofel

In a previous paper,1 the occurrence of (0001) and (0111) twins was reported for compression tests of 60-deg-oriented sapphire rods in the temperature range from 1100° to 1300° C. Subsequent to this initial work, additional tests have been conducted, and twinning has been found to occur at temperatures as high as 1500° C. Also, the temperature and strain-rate conditions for the two types of twins and for slip have been established in more detail. The present note covers this more recent work. The compression-test data are summarized in Table I. The techniques for identifying the twins are optical examination up to X1000 and X-ray analysis.' It is evident that (0711) twins are pre-

Jan 1, 1965

By M. Van Hecke, Y. Berube, L. M. de Smecht

Nitrogen solubilities in water at 100, 200, and 400 psi, in the temperature range 100 to 175C, were determined using an automated system involving flash evaporation and gas chromatography. Rates of gas transfer into a standard laboratory auto-clave were measured by the same technique. The rates at which a gas can dissolve into such a reactor were found to be close to the rates of oxygen consumption observed during the oxidation of several mineral sulfides, indicating that gas transfer might be a rate-limiting step in autoclave leaching.

Jan 1, 1977

By A. M. Gaudin

A preliminary study of silver ion adsorption by sphalerite in ion exchange column with influent electrolyte marked with radiosilver is described. Rapid ion exchange occurs at first followed by slow reaction controlled perhaps by solid state diffusion. One experiment with radiocopper instead of radiosilver is reported briefly.

Jan 9, 1951

Coal was produced in this state, by white men, at an earlier date than in any state west of the Mississippi River, and for many years its production was larger than that of any state in that area. The coal immediately adjacent to St. Louis was mined commercially earlier than elsewhere because of a ready market which could be reached by teams. Generally the coal seams are more or less "spotty" in character, and in many places openings made in thick coal could only be mined for a few years. All of the data available from state survey reports, county histories and a few other sources are shown in Table 66.

Jan 1, 1942

By Fenton Scott, Patrick Hannon

Some occurrences of lead-zinc mineralization in Mississippian carbonates of central Nova Scotia are briefly described. The results of geophysical and geochemical prospecting are presented. Because the deposits do not give a positive response to these indirect techniques it is necessary to site exploratory drilling through the development of geological concepts.

Jan 1, 1976

By John F. Frawley

This article in all probability will raise some serious doubts as to whether the coal industry-without a national, long-range commitment to coal-can, or should, attempt to meet the capital demands necessary to double coal production in the next 10 years. AMAX Coal, incidentally, doubled its annual coal productive capacity in the past five years from 11 million tons in 1969 to 22 million tons in 1974. Our 1973 annual report stated that we were aiming to triple our 1973 capacity to 50 million tpy by 1978.

Jan 5, 1975

By authority of the Secretary of War, and in response to frequent requests, the following suggested list of reading is issued by the War Department for the information of civilian engineers desiring to inform themselves on military subjects: These references have been selected, first, with a view to giving to engineers unfamiliar with the art of war a general survey of that sub-

Jan 1, 1916

By Ira A. Stark

Use of clay-working machinery in the metallurgical industry is by no means new. Extrusion- agglomeration as a basic operation in the non-ferrous field has a history of more than 50 years. This article advocates using the technique in the ferrous field where it might serve a useful purpose in today's operations. Many of the processes involved in production of iron ores result in fine powders, with a considerable percentage running finer than 200 mesh. In many instances, mining and related processing operations are located far from furnace operations. Shipping the powdered ore is impractical since handling losses and furnace losses from dusting would be excessive and powdered material must be agglomerated. The agglomerate must withstand the handling involved in transportation and here the continuous pugmill-extruder can be used to form a strong dense product.

Jan 6, 1959

ENGINEERS AVAILABLE (Under this heading will be published notes sent to the Secretary of the Institute by members or other persons introduced by members.) Graduate mining engineer, with 10 years' experience, having an office in New York, would like to represent a mining company as selling and purchasing agent, and general supervision if desired. Machinery agency considered. No. 259. Member, technical graduate, with several years' experience as engineer for a pyrites company, and as geologist and engineer for copper, nickel, and silver companies, desires a position as engineer or superintendent of mines. No. 260. Member, technical graduate, aged 29, with experience as draftsman, surveyor, and superintendent of iron and gold mines, and as construction engineer, is open for a position as mine superintendent, or in mine examination or construction. No. 261.

Jan 11, 1915

By D. H. Yardley

ENGINEERS and geologists find the magnetic compass unreliable in many mineral bearing areas because of local magnetic attraction. This is the case in the vicinity of many contact deposits, and particularly true in the Lake Superior district where iron formation is wide spread and causes wide fluctuations of the magnetic needle. One of the most useful instruments for geologic traversing or running grid and claim lines under these conditions is the dial compass which does not depend upon magnetism. Difficulties encountered in the field because of local attraction can be overcome through transit observation of Polaris or the sun, or use of the solar attachment. However, a field party often lacks the equipment or time for work of such accuracy and it is here that the dial compass finds its use.

Jan 3, 1954

By J. L. Shugert, W. C. Williamson

The paper covers the different phases of dust dissemination in the Butte mines and methods of its control. Dust inspection and reporting same are taken up in detail. Methods of dust and dust counting techniques with their associated problems are discussed. Effects of different methods of dust depression are demonstrated under controlled conditions.

Jan 1, 1950

By R. E. Lund, D. E. Warnes

SELECTIVE sulfation of individual constituents in ores or metalliferous products has received increased attention in recent years. The fluid-bed reactor with its advantages of close control of both temperature and atmosphere promises to have ap-

Jan 1, 1958