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Jan 1, 1908

I. PRESIDING OFFICERS. At all Business meetings of the Institute the President, or, in his absence, the Vice-President, or, in the absence of both of them, any other member of the Board of Directors to be chosen by the meeting, shall preside. At all other meetings of the Institute the President of the Council or, in his absence, one of the Vice-Presidents, if present, shall preside II. ORDER OF BUSINESS. At each Business meeting of the Institute the order of business shall be as follows 1. Reading of minutes of preceding meeting. 2 Report of the President. 3. Report of the Treasurer. 4. Report of the Secretary. 5. Election of Directors. 6. Reports of Standing Committees. 7. Reports of Special Committees. 8. Special Orders 9. Miscellaneous business. This order of business may be changed by a vote of a majority of the Members and Associates present in person or by proxy. The usual parliamentary rules shall govern all meetings of the Institute except in cases otherwise provided by the Constitution or the By-Laws. At all sessions of the Institute other than business meetings, the order of proceedings and the time of adjournment, shall rest in the discretion of the presiding officer

Jan 1, 1923

By Wilson Blake

As a part of a USBM-ASARCO cooperative rock-burst research program, a burstprone stope pillar at the Galena mine was successfully destressed. Destressing was accomplished by blasting a single line of long holes in the footwall of the vein. As a result of destressing, the pillar was fractured and softened; hence it yielded, releasing a large amount of stored elastic strain energy nonviolently. In addition, the high stress in the pillar was shifted out around the stope walls and in the sandfill. Both broad-band microseismic monitoring and seismic velocity surveys were used to evaluate the destressing test. The mechanics of destressing were determined by finite element computer model studies of destressing. Results of the field destressing test agreed remarkably well with the predicted results from the computer model.

Jan 1, 1973

By Benjamin Smith Lyman

THE importance of topography to geology is so commonly underrated as to deserve to be pointed out again and again. The relation of topography to the different branches of geology may be seen best by a glance at them all. Geology is well understood to consist of the observation of facts about rocks as materials of the earth (geognosy ), and the explanation of those facts (geogeny). The facts to observe are: I. GEOMETRICAL, as (1) structure, including the dip and strike at different points, the size, shape, and position of basins and saddles; (2) vertical section, that is, the thickness of rock groups and of their parts ; (3) horizontal or geographical position. II. PHYSICAL, such as texture, whether sedimentary or crystalline ; and, if crystalline, whether granitic, porphyritic, amygdaloidal, globular, or concretionary; whether compact or granular; coarse or fine; pervious or impervious; hard or soft; firm or tender; with cleavage or without; massive or thin; the microscopic structure; also whether magnetic or not; soluble or insoluble; fusible or infusible; and the constituent minerals. III. CHEMICAL, that is, the composition of the rocks and of their minerals and their affinities. IV. PALÆONTOLOGICAL, as what kind of fossils are in the rocks,

Jan 1, 1873

By P Shenon

THE Elk City district is in north-central Idaho about 60 miles east of Grangeville and near the headwaters of the South Fork of the Clearwater River (Fig. 1). At the height of its boom in the early sixties, Elk City had a population of more than 2000 people.1 Published estimates of the placer production from the district range from $10,000,000 to $18,500,000. Although the first quartz-vein location was made as early as 1870, very little gold was extracted from quartz ores until after the completion of the American Eagle mill in 1902. Between 1902 and 1932 a total of from $750,000 to $1,000,000 was taken from about six properties.

Jan 1, 1934

By Spencer R. Persik, Richard E. Munz

Measurements of many physical properties within an underground mine may be required as inputs to computer programs. These may be as simple as running/ not running signals from equipment, or they, may be representations of analog readings such as methane concentration. Similarly, outputs from computer pro- grams may control equipment located within the mine, as when air doors are opened or closed under computer control. This paper deals with the concept of electrical signal multiplexing and explains the role that multiplexing can play in comnunicating signals between the computer and locations within the mine. One multiplexer in particular, "DIRECTROL" (manufacturer by Cutler-Hamner Products), is examined in some detail, and its properties are discussed, including scan times, data security, recovery from cable failures, and recovery from power failures. Techniques of interfacing the multilexer to a computer are explained. Illustrations of the use of the multiplexer in mining applications are given.

Jan 1, 1983

By C. B. Murray

Our experience from time immemorial has been that the furnace sampler and analyst usually find one or two, and sometimes more, points less iron than the Lake Superior shippers, but, fortunately, their contracts are iron bound…

Jan 1, 1915

By Edward J. Ryan, E. A. Peretti

iV preliminary X-ray and metallographic survey of the ternary system Bi-In-Te revealed that the following isopleths could form quasibinary systems: InTe-Bi, InTe-InBi, InTe-BizTe3, and InzTe3-Bi2Te3. The nature of the InTe-Bi phase diagram was established by Bologna and Peretti.' This article presents the results of an investigation of the InTe-InBi system by thermal analysis, X-ray methods, and metallographic examination. The bismuth and tellurium were bought from the American Smelting and Refining Co. The tellurium had the following spectrographic analysis: 0.0001 pct Mg, 0.0001 pct Si, 0.0001 pct Fe, 0.0002 pct Al, and 99.999+ pct Te (by difference). The bismuth assayed: 0.0001 pct Mg, 0.0001 pct Pb, 0.0001 pct Fe, 0.0001 pct Cu, and 99.999+ pct Bi (by difference). The indium was obtained from the Indium Corp. of America and contained 0.002 pct Cu, 0.006 pct Pb, 0.01 pct Sn, 0.01 pct Zn, and 99.97+pct In. The alloys were made by melting the required proPortions of InTe and in evacuated, sealed quartz

Jan 1, 1967

By M. E. Learmont, I. Iwasaki

Grinding with steel media adversely affects the flotation response of galena. Electrochemical measurements, flotation tests, and AES, XPS, and STEM examinations were employed to identify interactions between galena and mild steel. Iron oxide, hydroxide, or sulfate species that formed on the galena surface upon contact with mild steel decreased its floatability, with the time of contact and aeration condition affecting the severity of the flotation depression. Parallel tests performed with an active metal, magnesium, indicated that floatability was also affected by the presence of a surface coating involving lead species.

Jan 1, 1985

[TWEEDY, A. M., and VOGEL, FELIX A.: The Briquetting of Flue Dust in the United States by the Schumacher Process, XLVII, [viii], 338. TWEEDY, GEORGE A., and BEALS, ROGER L.: Cyanide-Plant and Practice at the Minas del Tajo, Rosan'o, Sinaha, Mez., XLI, [xl], 324. Twin Falls plant, Peninsular Power Co., LI, 298. Twins, deformation lies in manganese steel, LI, 882. 2,000-Ton Leaching Plant at Anaconda (LAIST and ALDRICH) (With Discussion), LV, [xxiii], 866.]

Jan 1, 1918

By L. J. Howell, H. H. Kellogg

AN a previous paper' the phase diagram and vapor pressure of melts in the systems NaC1-ZrCl,, KC1-ZrCl,, and NaC1-KC1 (1:1 molar)-ZrC1, were reported. This note supplements the earlier paper with the results of electrical conductivity measurements on NaC1-ZrC1,and NaC1-KC1 (1:l molar)-ZrC1, melts. The design of the conductivity cell is shown in Fig. 1. Tungsten electrodes, A, were sealed into the Pyrex cell, C. That portion of the electrodes in contact with the melt was covered with a tight-fitting platinum cap. The electrodes were sur-

Jan 1, 1960

By J. E. Spurr

The region here discussed is that part of Western Nevada in which. during the last few years. discoveries of rich gold- and

Jan 1, 1906

By Robert C. Bolger, John H. Weitz

REFRACTORY clay, one of Pennsylvania's important nonmetallic mineral resources, occurs at several horizons in beds of Pennsylvanian age. The Mercer fireclay, of Pottsville age (Table 1), is the most important of these clays. A study of this fireclay has been conducted by the Pennsylvania Geologic Survey discontinuously over a period of seven years. The work has included field mapping of a rather large area, as well as petrographic, differen¬tial thermal, and X-ray studies of the fireclay. A comprehensive report on the project is now in preparation.

Jan 1, 1952

By G. R. Wilms

In a recent investigation1 on the properties of chromium, and of Cr-10 wt pct W and Cr-5 wt pct Mo alloys at elevated temperatures, it was found that intercrystalline cavities developed in all of these materials during tensile creep at 950°C, and that the cavities led to intercrystalline fracture. There were some interesting differences, however, between the cavities produced in the pure metal and those in the alloys; these differences, moreover, were associated with a difference in ductility. The relevant conditions of creep testing are specified in the captions to Figs. 1 and 3. Chromium showed the presence of quite large intercrystalline cavities, Fig. 1, and these were more or less randomly distributed around the boundaries. The chromium alloys, on the other hand, showed the presence of both small cavities and cracks at the grain boundaries, Fig. 3; it is apparent that the cracks are formed by the linking together of the small cavities. Moreover, the cavities and

Jan 1, 1960

By S. J. McCarroll

THE Three Kids mine, some six miles east of Henderson, Nev., is in a typical southwest desert area, with high dry summer heat and cool to cold winter seasons. The manganese deposit was located during World War I.1 During this period 15,000 to 20,000 tons of ore assaying up to 41 pct manganese were shipped. Interest in the deposit was not revived until the middle thirties, when experiments on the ore were initiated. Test work indicated possible recovery of only 70 pct by flotation, but in 1941 additional work was done at the Boulder City pilot plant of the U. S. Bureau of Mines and also by M. A. Hanna Co. As a result, the Manganese Ore Co. was formed and a plant utilizing the SO, process was constructed. Numerous operation difficulties ensued, and the plant was closed when the manganese situation in the country eased.

Jan 3, 1954

By R. W. Smith, R. W. Lai

Very recently there has been a quickening of research effort in the field of silicate mineral flotation, particularly as regards the flotation of beryl.' These studies have already contributed much to the understanding of both anionic and cat-ionic flotation of silicates. Of particular interest concerning anionic flotation has been the work done on heavy metal activation of silicates by M. C. Fuerstenau and co-workers.4,7 In addition. in the paper by Fuerstenau, Rice, Somasundaran and Fuerstenau7 attention was paid to low pH anionic flotation of beryl in the absence of activators. This subject was also covered in the papers by Avotins,3

Jan 1, 1967

By R. C. Hall

We are pleased to confirm some of the mechanical data presented by Dr. Detert on the 18 pct Ni marag-ing steel.15 Bar 3 in. in diam and containing 0.02 wt pct C, 18.5 Ni, 8.9 Co, 5.1 MO, 0.55 Ti, 0.05 Al, and balance iron has been examined in our laboratory. Cylinders 0.5 in. high and 0.4 to 0.5 in. in diam were cold-compressed from 3 to 40 pct reduction in height. Table VI shows some typical data; deformation in-

Jan 1, 1968

By Jos D. Weeks

On the extreme fringe of' the great Appalachian coal-basin is a long narrow detached coal-field, which is, in some respects, one of the most important in the United States. This field, about 90 miles long by 2½ to 16 miles wide, extends from the southwest corner of Somerset county, Pennsylvania, through Allegany and Garrett counties, Maryland, Mineral, Grant and Tucker counties, West Virginia, into Randolph county, West Virginia. In this distance four distinct sub-districts are recognized, the Wellersburg in Pennsylvania, the Cumberland-Georges creek in Maryland, and the Elk Garden and the Upper Potomac in West Virginia. The output of coal from the whole field including steam, domestic, smithing and coking-coal of the best quality, is about 4,500,000 tons annually. It is the nearest to tide-water of all the bituminous coal-fields which supply the great coal-markets of the Northern Atlantic seaboard ;

Jan 1, 1895

By H. Foster Bain

The recent admirable paper on the general subject of coalcutting machines presented to the Institute by Mr. E. W. Parker* leaves but little to be desired so far as the well-proven and widely-used machines are concerned. The general character of the machines in use and the range of their adaptabilities have been very well stated. It will be noted that in all cases these machines are being used in room-and-pillar work, and indeed (though attention was not directed especially by Mr. Parker to that point) they are practically confined to that work. It is probable that neither the chain breast- nor the pick-machine is, or can be, used to any great advantage in long-wall work.

Jan 1, 1900

By A. J. Weinig

THE Liberty Bell cyanide precipitate is unique in that it is apt to vary widely in composition in the course of very short, periods of time, and a method of refining and melting that would prove highly satisfactory at one cleanup would yield almost an hopeless "mess" it a second. Table I gives a general conception of the wide range in grade and composition of those raw precipitates. It is evident that no one standard flux could be expected to produce a high-grade bullion with such a widely variable precipitate, and that any method of treatment with acid requires most careful consideration. Refining by Acids Naturally, our first efforts to improve our precipitates were directed along the lines of acid treatment. Table II embodies the results of careful sampling and analysis of one cleanup at the time when wet refining reached its maximum development at this mill. We have now discarded all methods of wet refining, successfully replacing them by amore scientific method of flux calculation described herein, but it is believed that a general description of this wet refining is warranted as it throws some interesting side lights on acid refining in general.

Jan 3, 1916