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By Howland Bancroft

THE writer has observed that some confusion is experienced by many mining engineers in making vertical sections of ore deposits in mining properties which they have examined. Having much examination work calling for the correct interpretation of vein structure and the subsequent platting of the same on sections, it has occurred to the writer that the accompanying diagram may be of use to others who at times may be called upon to prepare numerous sections. For example, a great mass of data on-strike and dip of ore bodies is collected underground in separate

Jan 7, 1914

By F. J. Haller

The need for permanent, fireproof support indicated structural steel sets. Experience over the past six years, involving more than five miles of permanent underground openings, has proved that steel is permanent, safer and, in the long run, cheaper than either treated or untreated wood supports. Excavation is reduced, as are installation, transportation, and handling costs. A number of hazards are reduced or eliminated by the use of steel.

Jan 4, 1950

Data about production are practically non-existent before 1860. The Census of 1840 reported a small amount, and a number of small mines were opened in the forties, all of the coal being used locally, or hauled to consumers in wagons. Tonnages shown in Table 72 are estimated from those for which authority is given. Railroads reported coal tonnages carried in the state in 1878 and subsequent years for years ending June 30th;, it is not stated that the tonnage originated in the state. Considering this fact, and the considerable amounts used locally, the tonnages given in Table 72 are certainly not larger than the actual amounts produced.

Jan 1, 1942

By Norman E. Lehman

Pyrometasomalic mineralization occurs within meta-morphosed Paleozoic carbonates intruded by Laramide granodiorites. Two types of alteration developed shams in the district. The dominant type is post-magmatic which developed an early hydrous endoskarn phase, and intermediate anhydrous exoskarn phase, and a late hydrous phase affecting both sham types. A rare, second type is magmatic in age, lacks the hydrous phases, and developed a mineralogically-zoned endoskarn. Garnet exoskarns lacking associated plutonic rocks are stratigraphically controlled and contain an early anhydrous phase, an intermediate hydroxyl-bearing phase, and a late hydrous phase associated with base metal deposition.

Jan 1, 1981

By Dale K. Fields

With today's technological advances in mineral processing equipment, there is an increasing demand for accurate system control. This can only come about through representative sampling. The purpose of this paper is to guide in the selection of sampling equipment and outline design parameters for the cutters used in dry and wet sampling without adding redundant mathematical probability formulas. Special attention will also be given to the equipment used in conjunction with samplers and sampling system, such as feeders, crushers, chutes, launders, and controls.

Jan 10, 1979

By Rana P. Singh

Electrolytic metal reduction operatios in both aqueous and molten salt electrolytes are being studied by digital signal analysis. The purpose is to determine the relationship between the physical processes occurring in the cell and the frequency spectrum of the cell's fluctuating electrical parameters. The fast Fourier transform of cell voltage (in galvanostatic operations) or cell current (in potentiostatic operations) is computed on-line in real time for the electrorefining of zinc in aqueous acid chloride solutions.

Jan 1, 1984

By Thomas O. Breitling

The Mill Design Session at the Annual Meeting in New York next February will have a total of four papers. All of these papers will be concerned with the subject of in-plant dust in the hard-rock mining industry. The emphasis on efficient dust collection is timely, because dust is a problem not yet adequately covered in AIME papers. In general, dust collection should be the step following dust suppression. Dust collection and its return to the ore recovery circuit, or its waste to tailing are sources of added operating cost. If possible, dust should be kept in the main stream of ore flow by suppression.

Jan 1, 1970

All manuscripts intended for presentation at the February meeting of the Institute must be in the hands of the Secretary of the Institute not later than Monday, Nov. 23, 1914. This is the date at which the manuscript must be in the hands of the Secretary, and is not the mailing date upon which it leaves the author's hands. In case manuscripts are sent to members of Technical Committees, they must be in the hands of the Technical Committee a sufficient time in advance of Nov. 23 so that they may be in the hands of the Secretary on the date indicated.

Jan 10, 1914

By Theodore M. Barry

Work measurement is the most common of many titles given to determining the amount of human work required to do any job. A new technique-like most modern management tools-it still needs years of constructive research. Yet despite known imperfections, it is probably the most enthusiastically used tool of cost control developed in the last hundred years. Over 85 pct of all companies employing more than 100 workers in one of the major industrial areas use work measurement. For a good reason, however, this has not been true in the mining industry until very recently. The facts make an interesting story.

Nov 1, 1955

By Donald A. Dahlstrom

Stronger Than Armies This editorial by Dr. Dahlstrom is based on his acceptance speech of the 1976 Robert H. Richards Award-Ed. Many public figures are saying that the United States is facing the most critical period in its history, and many of us would agree. But people have always been saying this, and all of them were right. They were right two centuries ago when it took a revolution to give birth to the Republic; and they were right during our Civil War, Pearl Harbor, the Great Depression, etc.

Jan 6, 1976

By Walter Kauenhowen

The production of crude oil in Germany during 1933 totaled about 1,669,521 bbl., a slight increase over the 1,608,558 bbl. produced in 1932. This is an extension of a yearly increase which has continued uninterruptedly since 1928. The 1933 increase in production is due chiefly to developments in the Nienhagen field. The production of the Wietze and Oberg fields remained rather stable, while the Oelheim-Eddesse and Volkenroda fields showed decreases. Nienhagen Field.—This field furnished about 61 per cent of the total German oil production in 1933. Most of the drilling activity centered the north district near the village of Nienhagen, where the trend of

Jan 1, 1934

By L. T. Larson, P. M. Basinski

In the northern Reese River Valley uranium is corroded with Middle Pliocene zeolites. These zeolites were diagenetically derived from rhyolitic volcanic glass deposited in a saline- alkaline lake. X-ray diffraction, scanning electron microscopy, and chemical studies reveal clinoptilolite, analcime, and enonite to be pesent and that these minerals can concentrate at least 0.7% uranium from solution. Most anomalous drill cuttings contain zeolite and zeolites are believed to host the uranium. Research suggests the uranium mineralization is conceptually analogous to the Tono mine, Japan.

Jan 1, 1981

Very few data are available about production in this county. The amount mined was used locally, or shipped by river, until 1839 when the canal was completed to Dunnsburg. Only partial records for four years remain of canal shipments. Considerable coal was used locally by the iron works at Farrandsville for some years. Rail shipments started in 1861 and those shown are the estimated shipments of these mines as compared with the mines in other counties served by the Philadelphia and Erie Railroad, the total tonnages being given in the annual reports to the Auditor General. It is not likely that any coal used by the railroad is included in these figures. (Table 40.)

Jan 1, 1942

The Institute maintains for the use of members (and especially for the use of out-of-town members) a reading and writing room, where all usual office facilities are available, including telephone, telegraph, receipt, forwarding and care of mail and express packages, etc. A file of current magazines is also maintained in this room, and the Institute's staff will lend its best efforts to serving the members in connection therewith. The Institute also maintains for the use of its members free dressing rooms, library research department, etc. Attention is called to these facilities at the present time in the belief. that they may be especially useful to out-of-town members in connection with the Meeting.

Jan 5, 1918

By K. Y. Lo, R. S. C. Wai, R. K. Rowe, L. Tham

Laboratory tests for the determination of thermo-mechanical proper- ties of three rock types were performed at temperatures up to 400°C. Results showed that for the medium and coarse Granitic Gneisses, the coefficient of thermal expansion and Young's modulus are strongly temperature and temperature history dependent. A threshold temperature exists for each rock type above which material nonlinearity becomes important, and is associated with the progress of thermal cracking. Finite element computations were performed to illustrate the influence of material nonlinearity and boundary constraint on thermal stresses. Finally, a case history of thermal spalling was analyzed and it is shown that the results of analysis are consistent with field observations.

Jan 1, 1982

By Joseph W. Leonard

In a recent publication in the SME Transactions of September, 1975, Volume 258, entitled “Potential for Further Lowering Sulfur in Intensively Cleaned Coal at Mines,” the writer discussed: (1) technical findings useful for the management of reserves to further lower sulfur in intensively cleaned coal and (2) a future coal preparation plant concept for the intensive cleaning of sulfur. The purpose of this technical note is to (1) illustrate the nomographs that can be formed when recovery is phased in with previous work, (2) make note of the powerful potential for predicting future cleaning performance in unmined areas, and (3) discuss resulting mathematical interrelationships.

Jan 1, 1979

By J. A. Bownocker

THE production of oil in Ohio, in 1924, was characterized by no marked or surprising change. Low prices and the absence of promising territory made the year quiet. As is well. known, Ohio has reached a state of "settled production," and the most that can be expected for the ensuing few years is to maintain the output at approximately the present figure 1921 7,335,000 1922 6,781,000 1923 7,085,000 Geographically, the Ohio fields may be divided into three areas, each of which gets its main supply of oil from a different stratigraphic horizon.

Jan 3, 1925

By Joseph W. Leonard

Evidence is presented to show that certain coals can be super-cleaned, using present coal preparation processes, to reduce sulfur below levels that are commonly believed to be possible. The evidence points to the need to develop continuous sorting methods by which coal coming from a mine can be segregated so that different raw coal types can be processed separately to produce a super-clean coal in addition to coals cleaned to more common levels of sulfur. Evidence is presented and techniques discussed that may be applicable for making the method feasible.

Jan 1, 1976

PITTSBURG MEETING The One Hundred and Ninth Meeting of the Institute, for the presentation and discussion of technical papers, will be held at Pittsburg, Pa., Oct. 8, 9 and 10, 1914. This meeting is to be under the auspices of the Iron and Steel Committee, the Committee on Petroleum and Gas, the Committee on Coal and Coke, and the Committee on Non-metallic Minerals. Thirty papers have been secured by these Committees and will be presented at the meeting. These papers will be published in the September and October Bulletins. The Local Committee of Arrangements for this meeting is as follows: SAMUEL A. TAYLOR, Chairman. FRANCIS C. PHILLIPS. GEORGE S. RICE. C. F. V. Rys. KENNETH SEAVER. JOHN S. UNGER.

Jan 9, 1914

By J. G. Davis, P. C. Thakur

Hazardous methane gas in coal mining is receiving increased attention due to the increased US demand for coal which has resulted in the exploitation of deeper seams and the utilization of more productive equipment. Problems posed by methane emission has the Mining Research Division of Continental Oil Co. (Conoco) accelerating efforts that began in the early 1950's with Consolidation Coal Co. (Consol).1 The program's focus is on finding new techniques for degasification of virgin areas as well as control of methane in gob areas.

Jan 10, 1977