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Officials of the State Department have expressed their hope that a considerable number of technical men will take the examination for consular service. The Department recognizes that the interest of the United States will be served best if technical men are made available through these examinations for vacancies at points where their training will be of special value. Industrial engineers who have passed the con-sular examination will be assigned to industrial centers of Europe or South America. Mining engineers, chemists, electrical engineers, etc., will be assigned to industrial centers requiring special training.

Jan 11, 1919

By Robert F. Shurtz, William J. Verner

Three basic questions must be answered by an engineer performing an economic analysis of a mineral property: (1) How much can the company afford to pay for the property; (2) At what rate should the property be mined; (3) What will be the return on the investment. These questions often defy reasonable analysis, because at the point in time at which they must be answered little may be known about the grade of ore and the reserve tonnage. The purpose of this report is twofold. First, to derive a method of determining purchase price, rate of production and return on investment which is valid under varying conditions of ore grade and tonnage reserve; and, second, to apply this method to the Margay deposit in an attempt to evaluate it as a business enterprise. This is an actual economic analysis of an existing nickel-copper deposit fictitiously named the Margay. It was carried out for a mining corporation and proved to be the determining factor in the subsequent purchase and development of the property. All data referring to costs, quality and quantity of ore, etc., are accurate and truly represented. Prices used are obsolete but the method is not dependent on those variables. Basic assumptions for the analysis are given in Table I, page 71.

Jan 11, 1966

By B. K. Miller, George E. Moore

THE Missouri fire clays are here divided into plastic and semiplastic clays occurring as widespread bedded deposits in east central Missouri and flint and diaspore clays occurring as isolated "sink-hole" deposits in the north central Ozark region. Visual inspection was the first method used in clay prospecting. Thin overburden, hard sandstone "rimrocks," and the occurrence of diaspore float made this method particularly applicable in the flint and diaspore fields. The first drilling tool used was a hand auger. One man can drill 25 to 50 ft. per day at a cost of about 35 cents per foot. Holes can be drilled to a depth of 150 feet. Spud drills are often used where the over burden is hard. This drill uses a slotted earth socket bit. A two-man crew can drill about 100 ft. per day at a cost of about 35 cents per foot. Mechanically powered auger drills have been used extensively in wildcat drilling in the past few years. This type of drill furnishes a continuous set of cuttings. The practical depth limit with this drill is 50 to 60 ft. Two men can drill 300 ft. per day at a cost of about 20 cents per foot. Core drilling is used mainly to prove a known clay deposit. A two-man crew with a No. 22 Sullivan drill can drill about 30 to 40 ft. per day in soft clay, at a cost of about $1.25 per foot.

Jan 1, 1947

By A. M. Mirani

The Mine Planning System consists of two parts: 1. A Sales Forecast (Sales Planning) 2. A Production Planning. The mathematical methods of the sales forecast are the exponential smoothing and a method with Markov-Chains. By these methods the quantity of material (ore, coal) will be calculated for the time planned. These quantities constitute the points in the production-planning. In the production-planning , special kinds of networks are used for calculating the resources-equipment required, labor and costs. A special routine optimizes the sequence of the mining areas within the mine on the basis of the lowest costs. The resources can be limited. The activities will be shifted when the demand exceeds this limit. The basis of the production-planning are computer files, in which the geological data and economical evaluations are stored.

Jan 1, 1969

By Henry H. Angst

Tim history and efficiency of 40-ton capacity dump trucks for surface waste removal at the New Cornelia opencut copper mine, at Ajo, Ariz., are summed up in this paper. Tabulations of truck performance, together with detailed cost figures, prove the value of truck transportation for certain special operations at a large mine. Emphasis is given to the fact that truck transportation not only reduces the haulage costs but also reduces the breaking ground and shovel-loading costs per ton. The New Cornelia opencut copper mine is in the desert. The climate is ideal for seven months of the year, but the five summer months are uncomfortably hot. The elevation is 1820 ft. above sea level and the annual rainfall is approximately 6 inches. The ore body is a monzonite-porphyry deposit. The waste-rock capping consists of hard rhyolite, conglomerate and porphyry. All the material is hard and cannot be excavated without blasting. The rhyolite and conglomerate waste is very blocky. The weight of the rock in place is 2.16 tons per cubic yard. The average mine production per day is 22,000 tons of ore and 18,000 tons of waste rock, the latter consisting of surface rock and material within the ore body too low in grade to send to the concentrator. The rock is loaded by electric shovels with 4 1/2-cu. yd. dippers. The primary transportation of ore to the concentrator and waste to the dumps is by 30-yd. dump cars and oil-burning steam locomotives; therefore truck haulage of waste is a minor factor of the New Cornelia operation. However, as New Cornelia was one of the first mines to use large-capacity dump trucks for haulage, the results obtained are of interest. EQUIPMENT On the south side of the New Cornelia is a hill rising about 500 ft. above the normal surface elevation, roughly 1000 ft. in diameter at its base, called locally Arkansas Mountain peak. Exploratory drilling in this area developed additional ore that could be made accessible for open pit operation only by moving the mountain face a maximum distance of 400 ft. to the south. The slope of the mountain adjacent to the pit averaged 35°, and the small area involved precluded the use of train haulage for the removal of the 4,000,000 tons of waste estimated above the normal pit elevation. A study of dump-truck haulage at Boulder Dam and San Gabriel Dam led to the decision to use large-capacity end-dump trucks rather than smaller trucks, for the following reasons: I. The truck would have to withstand the impact of hard, heavy chunks, some of them weighing as much as 10 tons, which would be dumped from the 4 ½ -cu, yd. dipper. 2. The coarse, rocky, abrasive material would soon damage a light truck body. 3. The body of a small truck could not be efficiently loaded with coarse rock.

Jan 1, 1941

The plan for establishing relations of American industry with national labor on a definite basis so closely follows the channels of the efforts of Engineering Council, principally in the classification and compensation work, that it is of special interest to the engineering profession. The principles laid down under the following headings are about to he submitted to a referendum vote of the membership of the Chamber of Commerce of the United States. These principles were prepared by a special committee of the Chamber of Commerce after a long period of study of the entire subject of industrial relations. 1. Industrial enterprise, as a source of livelihood for both employer and employee, should be so conducted that due consideration is given to the situation of all persons dependent upon it. 2. The public interest requires adjustment of industrial relations by peaceful methods. 3. Regularity and continuity of employment should be sought to the fullest extent possible and constitute a responsibility resting alike upon employers, wage earners, and the public. 4. The right of workers to organize is as clearly recognized as that of any other element or part of the community. 5. Industrial harmony and prosperity will be most effectually promoted by adequate representation of the parties in interest. Existing forms of representation should be carefully studied and availed of in so far as they may be found to have merit and are adaptable to the peculiar conditions in the various industries. 6. Whenever agreements are made with respect to industrial relations they should be faithfully observed. 7. Such agreements should contain provision for prompt and final interpretation in the event of controversy regarding meaning or application.

Jan 6, 1919

In accordance with the requirements of our By-Laws I beg leave to submit herewith the report of the Library Committee for the year 1915. The activity shown by the sale of the institute publications during the year continues satisfactory, although not as large as last year. The total sales amount to $6,666.81, distributed as follows: Sale of Transactions...:: :. $4,585.42 Sale of Special Editions 553.17 Sale of Pamphlets and Bulletins 2,028.22 It should-be borne in mind that the sale of special editions was only begun last year,, and most of the members who did not have the special editions immediately bought them for their libraries. This year only a little less than half of the same number have been disposed of, and it is more than probable that from now-on the number will be considerably lessened.

Jan 2, 1916

By Breaux B. Castleman

The ultimate test of a business strategy is whether it achieves the owner's objectives. Most shareholders are interested in growth and profits, and share values on stock exchanges are very often closely correlated with profit growth and profitability measured as return on equity (ROE). Strategic management, then, involves managing investments or resource allocations to optimize long-term growth and real return on equity, within reasonable limits of risk. Figure 1 shows a plot of the five year, weighted average ROE of a number of communications companies against their stock market valuations in 1983, measured as a ratio of market value to book value. The principal explanation of the differences in the relative valuations of the individual stocks is historical ROE, weighted toward the most recent years. Further analysis demonstrates the added importance of growth in explaining the differences in stock market to book ratios. [ ] Research conducted by Booz Allen and others in recent years suggests that the relationships between ROE and market to book multiples hold true in industry after industry. Furthermore, we have found that in assessing business strategies for companies in these industries, the analyses should focus on whether proposed strategies are likely to lead to consistent long-term growth in real ROE, without excessive leverage. Our research also reveals, however, that these approaches to strategy assessment are not consistently applicable in the natural resource extractive industries. Figure 2 shows a similar comparison of market to book values against five year average ROE for a group of nine mining companies in 1983. Market value of the shares shows little correlation with ROE. [ ] Analysis of the data for other extractive industries indicates a similar pattern; that is, low correlation between share values and

Jan 1, 1985

By Bernard K. Asdell

Georgia, a state seldom considered to be an important mineral producer, has one surprising feature-it is the nation's largest producer of kaolin. Kaolin is a highly important raw material in the paper, rubber, ceramic whiteware, paint and chemical industries. In 1965, more than 2.7 million tons of kaolin were produced in this state, a 150,000-ton increase over the preceding year, and production continues to climb. Strictly defined, the term "kaolin" applies to a group of hydrous aluminum silicates in which kaolinite is the predominant mineral. Kaolinite is inherently white, non-abrasive, chemically inert, and of a very fine particle size, ranging from sub-micron to 40-microns equivalent spherical diameter. An electron-micrograph of kaolinite is shown in Fig. 1. The particles finer than about 2 microns are thin, elongated plates, hexagonal in outline. The larger particles, coarser than 2 microns, are predominantly vermicular in outline with a foliated structure. Table I shows a typical chemical analysis of commercial, wet-processed kaolin compared to pure kaolinite.

Jan 11, 1967

G. A. ROUSH,* South Bethlehem, Pa. (written discussion?).-Mr. Frey is correct in his impression that ice floats, but "frazil" ice happens to be the exception to the rule. The requirements for the formation of

Jan 12, 1919

Jan 1, 1913

MANY members of the National Societies died in service overseas during the World War. No memorial to these engineers has been set up but a unique and interesting suggestion has been made. While Edward Dean Adams, Fellow of the American Society of Civil Engineers, and Associate of the Ameri-can Institute of Electrical Engineers, ,vas in Belgium last June as delegate of the National Societies, En-gineering Foundation, and Engineering Societies

Jan 12, 1927

By Robert C. Weed

Leaching in place at Cananea began in the 1920's on a limited scale. The first plants were small wooden boxes located underground in the Capote and Oversight mines, and output was low. Scrap iron was used as precipitant. Later several other small plants were started up. Leaching was limited entirely to underground areas, and production remained low. The Veta precipitating plant, the first on a larger scale, was put into operation in the late 1920's. After a period of intermittent service it was rebuilt in 1946 and has since been running continuously.

Jul 1, 1956

By J. W. Snavely

WITH all the advantages of handling bulk materials by means of belt conveyor also go some problems, one of the most persistent being that of cleaning. When sticky materials are being carried; the build-up of material on the return idler rolls results in difficulty of belt training. Much attention has been given to the problem of cleaning conveyor belts, and a great variety of cleaning devices have been developed. Even the best involve troublesome maintenance, and none can completely remove the fine particles imbedded in the belt cover, which cause rapid wear of the return idler rolls, and at the same time, of the belt cover as well.

Jan 12, 1951

PRESIDENT GEORGE OTIS SMITH, District 4 WASHINGTON, D. C. PAST PRESIDENTS SAMUEL A. TAYLOR, District 3 PITTSBURGH, PA. E. DEGOLYER District 0 NEW YORK, N. Y. FIRST VICE-PRESIDENT W. H. BASSETT District 1 WATERBURY, CONN. TREASURER KARL FILERS NEW YORK, N. Y.¬ SECRETARY H. FOSTER BAIN NEW YORK, N. Y.

Jan 1, 1923

By Walter Weeks

THERE is very little useful material in the litera-ture on the construction of manometers, so each experimenter must devise his own instrument. I have experimented for a number of years and have finally built one that is satisfactory. If we are to obtain accurate friction factors in mine-ventilation problems we must use accurate instruments. The most simple and convenient instrument for the mea-surement of small pressures is the inclined manometer or U-tube. By changing the angle at which the tube is set, any desired magnification of the pressure reading may be obtained. The first question in regard to the manometer is: What liquid shall be used? Alcohol, in my opinion, is the best. It does not cling to the glass and it does not attack the rubber tubes. The next problem is the setting of the instrument at the proper angle. One method is illustrated in Fig. 1. The base plate AC is made horizontal by a level bubble. The plate AB, which carries the U-tube, is hinged at A. The angle z which AB makes with the horizontal may be made any value by pinning the end B at the calculated position on the arm CD. Such an instrument may be designed to read directly in inches of water if a liquid of constant specific gravity is used. If the specific gravity varies, a calculation is necessary to convert the reading into inches of water.

Jan 1, 1923

By Harry H. Angst

THE history and efficiency of 40-ton capacity dump trucks for surface waste removal at the New Cornelia opencut copper mine, at Ajo, Ariz., are summed up in this paper. Tabulations of truck performance, together with detailed cost figures, prove the value of truck transportation for certain special operations at a large mine. Emphasis is given to the fact that truck transportation not only reduces the haulage costs but also reduces the breaking ground and shovel-loading costs per ton. The New Cornelia opencut copper mine is in the desert. The climate is ideal for seven months of the year, but the five summer months are uncomfortably hot. The elevation is 1820 ft. above sea level and the annual rainfall is approximately 6 inches. The ore body is a monzonite-porphyry deposit. The waste-rock capping consists of hard rhyolite, conglomerate and porphyry. All the material is hard and cannot be excavated without blasting. The rhyolite and conglomerate waste is very blocky. The weight of the rock in place is 2.16 tons per cubic yard. The average mine production per day is 22,000 tons of ore and 18,000 tons of waste rock, the latter consisting of surface rock and material within the ore body too low in grade to send to the concentrator. The rock is loaded by electric shovels with 4 ½ -cu. yd. dippers. The primary transportation of ore to the concentrator and waste to the dumps is by 30-yd. dump cars and oil-burning steam locomotives; therefore truck haulage of waste is a minor factor of the New Cornelia operation. However, as New Cornelia was one of the first mines to use large-capacity dump trucks for haulage, the results obtained are of interest. EQUIPMENT On the south side of the New Cornelia is a hill rising about 500 ft. above the normal surface elevation, roughly 1000 ft. in diameter at its base, called locally Arkansas Mountain peak. Exploratory drilling in this area developed additional ore that could be made accessible for open pit operation only by moving the mountain face a maximum distance of 400 ft. to the south. The slope of the mountain adjacent to the pit averaged 35°, and the small area involved precluded the use of train haulage for the removal of the 4,000,000 tons of waste estimated above the normal pit elevation. A study of dump-truck haulage at Boulder Dam and San Gabriel Dam led to the decision to use large-capacity end-dump trucks rather than smaller trucks, for the following reasons: 1. The truck would have to withstand the impact of hard, heavy chunks, some of them weighing as much as 10 tons, which would be dumped from the 4 ½ -cu. yd. dipper. 2. The coarse, rocky, abrasive material would soon damage a light truck body. 3. The body of a small truck could not be efficiently loaded with coarse rock.

Jan 1, 1941

By A. A. Gustafson

The Freeport Sulphur Co. built a portable crusher in 1944 that solved a problem that none of the crusher manufacturing companies contacted were able to do. Two of these crushers have now been in service for 6 years, giving satisfactory service in handling a million tons per year, and having a capacity of over 2000 long tons per 8-hr shift. These machines reduce ton size blocks of sulphur to 12 in. and also feed the conveyor system at the rate of 350 long tons per hr per machine.

Jan 10, 1950

By Frank R. Milliken

Before the rather sudden economic downturn in recent months, shortages of materials were painfully felt throughout the US. The current recession has provided a temporary relief here and there-but energy fuels and a number of staples such as sugar are still in short supply. This is an unsolved and fundamental problem that will haunt us again as the economy turns up. There is an awareness that the nation faces a widening supply gap in many of its most basic materials-from asbestos to tungsten-as evidenced by recent studies and government reports, and by the Secretary of the Interior's annual warnings about the mounting seriousness of the problem.

Jan 3, 1975

By R. H. Thorpe

Longwall working in Britain developed to overcome problems arising from depth of seams causing roof and ventilation difficulties. This system became very widespread particularly in the thicker seams, where faces of up to one mile in length were not uncommon. In the thinner sections, in order to remain competitive, the longwall undercutting machine was developed. Following the development of the coal cutter, every other aspect of the face operation was examined and mechanized as it became a bottleneck to output and efficiency. The face system itself was modified and workings concentrated with the same objectives.

Jan 1, 1977