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By Robert A. Melton

Since many of the easily mined, continuous, thick coal seams in the Appalachian Region have been exhausted, new exploration and mining is being directed toward less continuous seams that are under more cover and are more difficult to mine. The direct results of this are that more money and time and more expertise and data are needed to plan and open new coal mines today. It is also becoming apparent that the old methods of assimilating and preparing information needed for mine planning are inadequate to meet the needs of today's modern mining engineer, especially in the areas of data gathering, storage, retrieval, preparation, and interpretation. The system described here allows assimilation of old and new core data in a relatively quick, accurate, and efficient manner. The system is a set of computer assisted procedures consisting of the following four basic steps: 1) raw data collection, computer input, storage, and graphic preparation, 2) geologic profile correlation and establishment of seam continuity, 3) computerized data posting of important seam parameters, 4) geologic and planimetric analysis for mine planning.

Jan 1, 1977

By F. W. Maclennan

PAPERS by D. B. Scott, E. G. Deane, and J. H. Hensley, Jr.1 describe the succession of mining methods used in the Miami mine—squarelset system, shrinkage stoping, top-slicing method, and the undercut caving system which was then being used, and which embraced the use of finger raises. The last-named system worked well but when the rich ore was exhausted it became necessary to reduce costs so as to make available a low-grade ore containing an average of less than 0.9 per cent. total copper with less than 0.8 per cent. in sulfide form and with no precious-metal values. There was then developed for this low-grade ore the system of separate large block-caving stopes, in lateral dimensions 150 by 300 ft., or 150 by 150 ft., with intervals between stopes of the same size so that subsequently these pillars may be similarly mined. The results have been most favorable. Under the previous system the production of ore per man-shift for all underground labor was 8 tons. The present production per man-shift underground is 28 tons. In starting this work the problems were: 1. How the ground would cave above the stopes. 2. Whether in the first stopes caving would encroach on the pillars as laid out. 3. Whether in subsequent mining of the pillars waste filling would be drawn from the previously caved adjacent stopes. Fig. 1 is a small key plan for showing the location of cross-sections as well as of ore mined and the limit of the escarpment and limit of cracking on the surface caused by the caving of the capping overlying the ore

Jan 1, 1929

By O. W. Ellis

RECENTLY there has been a considerable revival of interest in the effects of the various elements commonly added to brass for the purpose of increasing its strength. For many years the work of Guillet2? alone gave reliable information in this regard. Even today his determination's of the coefficients of equivalence of the various elements relative to zinc in brass are those universally employed in industry. This is so because these coefficients have stood the test of time-their substantial correctness has been proved in almost universal practice. It is not our intention to discuss here these coefficients or their use. Rather do we wish to emphasize the need for further systematic studies of the mechanical properties of the ternary systems of copper, zinc, and other individual elements. Since Guillet published the results of his first investigations Millington,16 Smalley33 and Thibaud45 have added somewhat to our information. In general they have confirmed the findings of Guillet, which may be stated in the following rather general terms: 1. The addition of aluminum to the 70:30 and 60:40 brasses progressively increases their hardness and strength and reduces their ductility and resistance to shock. 2. The addition of small amounts of iron to a 60:40 brass improves its strength without affecting its ductility. 3. The addition of small amounts of manganese to a 60:40 brass causes a progressive increase in its strength and reduction in its ductility. A considerable amount of information has been amassed in regard to the effect of nickel on brass (9, 22, 41) which it is unnecessary to refer to here, in view of the scope of this paper.

Jan 1, 1929

By Chikaosa Tanimoto

INTRODUCTION The committee on Rock Mechanics, Japanese Society for Civil Engineers, has been discussing 'soft rock engineering in Japan' and presented several papers concerning dam, tunnel, bridge and slope constructions to International Symposium on Weak Rock, Tokyo 1981. This is the summarized paper based on References of Okamoto et a1 (1981), Iida et a1 (1981), Working Group on Tunneling-JSCE (1981), Working Group on Bridge Foundations-JSCE (1951) and Kikuchi et a1 (1981), which can convey general view on engineering experiences with weak rocks in Japan. From the point of view to the origin and/or distinctive physical properties, weak rocks in Japan may be classified into (1) sedimentary, (2) weathered, (3) low welded-pyroclastic and (4) fractured ones. Their typical characteristics are summarized in the following section. Concerning dam foundations on soft rock, several hundreds have already been constructed and, at present, nearly one hundred are under construction or at planning stage. These dams, almost without exception, have some problems such as site selection, material selection for fill-type and concrete dams, design of dam and its foundation, and construction procedures, requiring special ingeneous and cautious measures to cope with the local geotechnical difficult situations. In tunneling, for the decade of 1970s, the number of tunnels in soft rock either completed or under construction was at least 160, including Seikan Tunnel of 53.9 km long, Nakayama Tunnel of 14.8 km long and so on. Most of these tunnels are distributed in the northern half of Mainland, consisting of a basement of Paleozoic strata and Plutonic rocks, overlayed by Neogene Tertiary formations which include large

Jan 1, 1982

By P. W. Bridgman

THE thesis of this article is that the age of Newton is now coming to a close, and that recent scientific discoveries have in store an even greater revolution in our entire outlook than the revolution effected by the discovery of universal gravitation by Newton. The revolution that now confronts us, arises from the recent discovery of new facts, the only interpretation of which is that our conviction that nature is understandable and subject to law arose from the narrowness of our horizons, and that if we sufficiently extend our range we shall find that nature is intrinsically and in its elements neither understandable nor subject to law. The new experimental facts are in the realm of quantum phenomena. Comparatively little has been written for popular consumption about this new realm which has opened in the last fifteen years. The man in the street has been much more interested in relativity, which to him has seemed extremely interesting and revolutionary. Occasionally, however, there has filtered down to him the news that nearly all the theoretical physicists are occupied with a new order of phenomena which they find very much more exciting and revolutionary than any in the realm of relativity. For after all is said and done, the practical effects of relativity, measured in ,dollars and' cents or in centimeters and grams, are exceedingly small, and require specially de- signed experiments executed by men of the highest skill to show their existence at all. The phenomena with which quantum theory deals, on the other hand, are of the greatest practical importance and involve the simplest aspects of everyday life. For example, before the advent of the quantum theory no one could explain why a tea kettle of water boiling on the stove should not give out enough light in virtue of its temperature to be visible in the dark; the accepted theories of optics demanded that it should be visible, but every burned child knew that it was not.

Jan 1, 1929

By R. W. Raymond

(Cleveland Meeting, October, 1912.) UNDER the names of Conservation, Social Justice, the New Nationalism, and Progressive Democracy, many earnest reformers are calling for a new system of Federal government to replace the one which they ascribe to our fathers, and declare to have been outgrown. They are proposing the lease by the United States of certain natural resources on the public domain, for the profit of the U. S. Treasury, instead of the sale of such resources to private citizens or associations of citizens. In the present paper, I shall try to show that this notion is neither new nor good. It is clear that the United States is owner, as well as sovereign, of public lands acquired through conquest or purchase from other nations, as it was owner of the public lands expressly ceded to it by the original thirteen States. Its policy with regard to such lands involves, therefore, two entirely distinct questions: What shall it do as owner ? and, What shall it do as sovereign ? The latter question, it must be confessed, has played but a small part in our history. All the prerogatives of sovereignty which were not explicitly conferred upon the Federal government by the original States were retained by them. The ownership or control of precious or other metals or minerals in the earth, for instance, was thus reserved to the several sovereign States. New York, South Carolina, and other States have passed laws on this subject, without regard to Federal authority. As new States have been successively admitted to the Union, the tacitly accepted theory has been,. that they thereby acquired all the reserved rights of the original States. These newer States largely outnumber the first. thirteen; and it is inconceivable that they would submit to any deprivation of sovereignty based on historical grounds. One of them-Texas-came into the Union by its own voluntary

Oct 1, 1912

I have the honor to submit herewith the report of the Secretary for the year 1915 showing the principal activities of the Institute: Meetings.-The 110th Meeting, including the Annual Business Meeting, was held in New York City, Feb. 15 to 17, 1915. The full report of this meeting is given in Volume LI of the Transactions. The number of papers presented was 53, and the attendance was 357 members and guests. The 111th Meeting was held in San Francisco, Cal., Sept. 16 to 19, 1915. Sixty-eight technical papers were presented, and the attendance was over 400 members and guests. The full report of this meeting is given in the Bulletin for December, 1915. Local Section.-A new, strong Local Section of the Institute, with head-quarters in Arizona and known as the Arizona Section, was formed during 1915. Affiliated Student Societies.-Three new Affiliated ,Student Societies were recognized in 1915 consisting of the Pick and. Hammer Club of the University of Oklahoma, Mining and Metallurgical Club of the Univer-

Jan 2, 1916

By H. Tanner, T. Heikkinen

In1950 studies concerning mining and milling of the approximately 17 million tons of ore remaining at Outokumpu revealed the surface facilities for economical treatment were inadequate. The two shafts would soon be too far from the mine workings. Moreover, in spite of several extensions, mill capacity was insufficient and recoveries were not satisfactory. Therefore it was decided in 1951 to sink a new shaft and to build a new mill and auxiliary surface buildings around the shaft. The new shaft was sunk near the center of the remaining orebody, about 650 ft from the ore to the footwall side. This location placed the main part of the shaft as well as the crusher rooms and the ore bins around the lower end of the shaft in the firm and strong mica-schist.

Jul 1, 1955

By L. G. Huntley

Points out differences between the new, more liberal, law passed by the Colombian Congress and the law passed in 1919, gives a few facts about the pipe-line concession granted to a Canadian company, and tells of new drilling developments. PROBABLY the most important development in the Colombian oil situation during the past year was the passage by Congress of a new petroleum law, which went into effect Jan. 31, 1923. The principal points of interest in which this new law changes or improves the previous one are as follows: Law 120 of 1919 provided that one person or corporation could not acquire more than three exploitation zones. of 5000 ha. each, and royalties were based on a sliding scale, to wit: 6 per cent. royalty on lands 400 km., or more, from the ocean; 8 per cent. on lands 200 but not over 400 km. from the ocean, and 10 per cent. royalty on lands located less than 200 km. from the ocean. Rentals were fixed at 10 centavos per hectare for the first year; 20 centavos for the second year; 50 centavos, third year, and $1 (one peso) yearly thereafter. Under this law the term of the lease was fixed at 20 years and, at the discretion of the government, could be extended for 10 years additional. After the expiration of the lease and its corresponding extension, the machinery and other material placed upon the property would vest in the government. A bond of 20,000 pesos was also required of the lessee to guarantee faithful performance of his contract.

Jan 3, 1924

By F. Weston Starratt

The opening of a new large-scale beneficiation plant is always news, but the start-up of Cleveland-Cliffs Iron Co.'s Eagle Mills near Ishpeming in Michigan's Upper Peninsula early in October is of particular interest because of the completely different type of operation being carried on at this plant. The ore boat which left Marquette, Mich. on the 3rd of October bound for the plant of Wisconsin Steel Division of International Harvester, not only carried the first output of this new mill, but also carried the first agglomerate made from the Upper Peninsula's jasper ore, the first commercial output from an updraft traveling-grate furnace, and the first large-scale commercial application of the balling disk, also called the flying saucer, to the agglomeration of an iron flotation concentrate.

Nov 1, 1956

By George W. Maynard

In the Journal of the Iron and Steel Institute for the year 1878, in the account of the proceedings of the annual meeting in March of that year, when Mr. Bell read his paper On the Separation of Phosphorus from Pig-Iron, occurs the following statement, as part of the reported discussion of that paper: " Mr. Sidney Thomas stated that he had succeeded in effecting the almost complete removal of phosphorus in the Bessemer process. Experiments had been carried on at Blaenavon, with the co-operation of Mr. Martin, on quantities varying between 6 lbs. and 10 cwt., and some hundred analyses made by Mr. Gilchrist (who had the conduct of the experiments from the first) showing the removal of from 20 per cent. to 99.9 per cent. of phosphorus in the converter. He believed the practical difficulties in the way had been overcome, and that Cleveland pig might be made into good steel without any intermediate process. He hoped on a future occasion to lay full details before the Institute." I was present at that meeting, and I doubt if any one in the hall knew, either by sight or name, the young man who had dared to rise in that august body and claim that he had accomplished that after which the great metallurgists of Europe had been unsuccessfully striving ever since Mr. Bessemer's great discovery. I remember distinctly the pitying smile of derision and the stony stare

Jan 1, 1885

By K. Fallenius

Since 1970 a new series of pneumo-mechanical flotation machines has been developed by Outokumpu Oy. The cells have a completely new type of mechanism based on a recently-developed theory of conditions necessary for dispersion of large amounts of air. The mechanism was developed in 3 cu m cells and scaled to 16 cu m cells. Rotor and stator description, scale-up theory, and practical experience with the 16 cu m cell are presented.

Jan 1, 1976

For the benefit of those of our members who are considerable holder; of securities, but owing to their isolated situations are not in close touch with the metropolitan market and current quotations, we are publishing two very interesting graphs, showing the course of the bond and stock markets in New York over a long period. These graphs are-fui?riished through the courtesy of the financial department of the New York Tribune.

Jan 8, 1919

By W. E. Brigham, P. W. Reed, J. N. Dew

By Geo. W. Bain

PRODUCERS of building stone have had to seek new and attractive uses for their output to supplement the diminished orders for standard products. Lunar is the direct result of the need of new outlets for marble and is. probably the most ingenious and attractive type to reach the market in a quarter of a century. It is a highly translucent stone which retains the same glistening sparkle in transmitted light that marble exhibits by incident rays. This sparkle sets it apart entirely from translucencies made of glass or even onyx, alabaster, and the distinctive exceedingly fine textured calcite marbles produced in Alabama and quarried formerly in northern Vermont and Quebec.

Jan 1, 1936

FOLLOWING the presentation of the papers by Messrs. Mahan and Butler, the discussion printed below ensued. A. C. LANE* With particular reference to the New England con-sumer, I entirely agree with Mr. Mahan that intelli-gent marketing methods will do a good deal, but there is more than one way of improving them. For instance, coal can be shipped best to New England about this time of year-after the storms of the winter and before the movement of crops in the summer. For that reason there ought to be seasonal freight rates. This will be agreed to by most coal men if you will ask them, especially those who are connected with large concerns like the Metropolitan Coal Co., and yet they do not get seasonal freight rates partly because the railroads are afraid if they once reduce them they will never have a chance to get them back again. But it would be an improvement to have seasonal freight rates. Another thing: When we are buying in New England we want really a certain amount of heat value in our coal. There is no great advantage in our buying ash, nor is there any particular advantage in the railroad shipping ash and clogging the circulatory system of the body politic any more than clogging the circulatory system of the physical body. It would be desirable if the wholesaler, and to some extent the retailer, could guarantee the amount of ash or sell their coal on heating value. If you are interested in that you will find some interesting charts, in "Anthracite Coal Costs Analyzed," a pamphlet issued by the Anthracite Coal Consumers Association, Inc., New York City, as to rates from various and sundry points for bituminous and anthra-cite coal from the field to New York, Buffalo and Chi-cago. Here in New England they are both up against the competition of oil. About 3 or 3 1/2 bbl. oil will do the work of a ton of coal. One of my millionaire friends who is well posted on the situation is putting oil in his Commonwealth Avenue house because it is the most economical. Moreover, we can get Welsh coal from across the water (and help equalize this matter of exchange with Europe) in close competition with Penn-sylvania coal.

Jan 4, 1928

By D. M. Francois-Bongarcon

The idea of parameterizing reserves has only been formalized and scientifically applied for a few years. Its most fully developed application, that of open pits, has been operational only since 1976. Two new versions which have just been issued provide a complete solution to the problem and also a powerful tool for mine planning, and they open up a new field of investigation. This paper describes the basic principles for parameterizing reserves, their application for open-pit mines, the algorithm used, the physical interpretation of the results obtained, their economic use as well as the first prospects offered by a complete parameterization in tm of (I. ti), or of the metal price.

Jan 1, 1984

By R. R. Angel

Drilling rate is a parameter that should be considered in determining the volume requirements for air and gas drilling. The use of past methods which ignore the effects of the solids content upon the pressure and velocity of the annulus flow stream can result in undercalculation of the required volurne by as much as 50 per cent. A vertical-flow equation is presented for determining volume requirements. This equation includes the effect of the solids that are transported up the annulus in the flow stream by incorporating the drilling rate as one of the parameters. The effect of down-hole temperature on required circulation rates is also ana-lvzed. A simple approximate method of determining volume requirements is presented. This method is more accurate than the methods used in the past. Hole cleaning difficulties are analyzed for a recent air drilling job where past methods indicated that - excess air was being used. Sample curves of calculated boitom-hole pressures are presented for air and gas drilling in several hole sizes. INTRODUCTION In certain areas the use of air or natural gas as a circulating medium for drilling oil and gas wells is becoming a common practice. Large increases in penetration rate and bit life are achieved through the use of these media in preference to mud or water. Drilling rates as high as 90 ft/hr have been obtained in shales. The importance of maintaining adequate circulation rate is generally recognized; however, much disagreement exists among drilling operators as to what constitutes "adequate" circulation rate. In quarry drilling, where annular velocities can be accurately determined, an annular velocity of 3,000 ft/min of standard air is required for best results in rocks having approximately the same density as those commonly penetrated in drilling oil or gas wells'. Although this standard air velocity has proven satisfactory for quarry drilling, some oil and gas well drilling operators believe that an equivalent annular velocity of more than 4,000 ft/min is required; others believe that as little as 2,000 ft/min . is sufficient. Much of this disagreement results from determining the required circulation rates with methods which fail to incorporate the drilled solids in an equation which is applicable to vertical flow. Hughes Tool Co. Bulletins No. 23' and 23-A3 present data for determining circulation rates based on the Weymouth formula. These data do not include the drilling rate as a parameter and, therefore, neglect the effect of the solids being transported up the annulus. In spite of this apparent defect and the fact that the Weymouth formula is not applicable to vertical flow, the Hughes data have well served the drilling industry in many areas and are important and timely contributions to the science of air and gas drilling. The Hughes data purposely omit a correction for increasing down-hole temperature. At slow drilling rates this effectively compensates for the use of a formula which is not valid for vertical flow; however, volumes determined by the Hughes method are not sufficient to support rapid drilling rates at moderate and great depths. For example, Phillips Petroleum Co.'s Cauthorn "D" No. l in the Vinegarone field for Val Verde County, Tex., was air drilled from 1,500 to 9,300 ft using a compressor delivering 1,400 cu ft/min. The 8 3/4-in hole was drilled with 5-in. drill pipe, and drilling rates as high as 90 ft/hr were obtained between 7,000 and 9,300 ft. No water or caving hole was encountered. At 7,728 ft it was necessary to wash-out 60 ft of cuttings to reach bottom after a trip to change bits. At 8,130 ft a twist-off occurred and the drill col-lars were stuck in drill cuttings. These difficulties indicate that the 1,400 cu ft/min of air was not sufficient to keep the hole clean. Hughes data indicates that 1,180 cu ft/min is sufficient to produce an annular ve-

Jan 1, 1958

By U. N. Bhrany, N. Arbiter

F. C. Bond (Consulting Engineer, Processing Machin-Dept., AllisChalmers Manufacturing Co., Milwaukee) This is a very comprehensive paper. It deals with 1) size distribution functions, 2) energy-particle size relationships, and 3) criteria for grinding efficiency. The method of analysis used consists of tracing the increase and decrease of successive Tyler scale screen fractions as grinding progresses. The treatment is based upon the assumption that the work done in grinding is concentrated entirely upon the coarse size fractions in the mill. It is postulated that when a feed consisting entirely of particles of one size fraction is batch ground that finer fractions increase at a constant rate as grinding progresses, until finally each in turn begins to be ground and to decrease in amount. It is shown that under these conditions the empirical Gates-Gaudin-Schuhmann log-log size distribution plot can be logically explained. It is difficult to imagine any condition of ball mill operation, or any probability analysis, which would result in no grinding contacts on the finer particles present. However, the authors' postulate must be accepted if their conclusions are to be sustained. They conclude that the equation expressing the for mation rate of each size fraction can be resolved into the G.-G.-S. size distribution equation, and that the curvilinear portion of the log-logsize distribution line represents the only particle sizes which are being ground as well as produced. The author's statement that the G.-G.-S. Eq. 4 applies only to the finer portion of the size distribution while the Rosin-Rammler Eq. 6 applies over the whole size distribution range certainly supports the view that an exponential equation of the Rosin-Rammler type corresponds more closely to actual size distribution than does the power law G.-G.-S. equation. However, the G.-G.-S. equation is used to derive Eq. 8 and Eq. 9, which state that the energy required to grind a ton through a particular mesh varies inversely as the particle size to the exponent -a , whic h is the slope of the extended G.-G.-S straight line. This is stated to apply to both batch and continuous grinding. The G.-G.-S. slope exponent thus becomes very important in all crushing and grinding analyses by this method. The authors include some data which can be used to test their conclusions, as described below: We will consider grinding a feed composed of 14 mesh (1190u) to -200 mesh (74u). The average of 17 Allis-Chalmers grindability tests on quartz gives a work index (Wi) of 12.77. The -200 mesh product should have 80 pct passing 41.6u or P = 41.6. The equivalent 80 pct passing size of the 14 mesh feed particles is considered to be the particle diameter, as is true for spherical particles. Thus F is 1190u. In the work index equation 10 wi 10 wi 127.7 127.7 P f 41.6 1190 = 16.1 kw-hrperton. In Table I the ball mill exponent for quartz is 1.0 and from Eqs. 9 and 10: w=kw-hr/ton =Constan/(do/di) = 16.1 ton so that (1190) Constant/ Constant and the Constant equals 259. The tons per horsepower-hour value is 0.0464, in agreement with Table IV. The exponents for other minerals are listed in Tabl e 11. In Table IIA, the kilowatt hours per ton required to grind these minerals between the same sizes as the quartz, both by the authors' method and the work index equation, are listed. According to the authors kw-hrperton = 259/(16.1)".

Jan 1, 1961

PRESIDENT AND DIRECTOR D.C. JACKLING SAN FRANCISCO, CALIF. PAST PRESIDENTS AND DIRECTORS NEW YORK, N. Y. R. C. ALLEN- CLEVELAND, OHIO VICE-PRESIDENT, TREASURER AND DIRECTOR KARL EILERS-* NEW YORK, N. Y. VICE-PRESIDENTS AND DIRECTORS HENRY KRUMB NEW YORK, N. Y. PAUL D. MERICA . NEW YORK, N. Y. H. G. MOULTON NEW YORK, N. Y. HARVEY S. MUDD Los ANGELES, CALIF. WILFRED SYKES CHICAGO, ILL.

Jan 1, 1938