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By AIME AIME

NEARLY two hundred 'engineers attended the dinner given at the Hotel Pennsylvania on Monday-evening, Oct. 10, to the delegation from the American l3nginiering Societies to Great Britain and France when the John Fritz Medal was presented to Sir Robert Hadfield and to Eugene Schneider. Representatives of the British and French Governments ' and of foreign engineering societies gave to the event an international aspect unique in gatherings of engineers. Messages from men distinguished in science, statesmanship and diplomacy were read. Medals struck by the French Government were presented to the general chairman of the deputation, to the chairman of each' individual delegation and to the president's of the four Founder Societies. The meeting was regarded by engineers as formally ushering in a definite movement for world unity in the engineering profession. J. Vipond Davies, president of the United Engineering Society, acted as toastmaster. The speakers ,were Ambrose Swasey, Charles F. Rand, F. B. Jewett, A. S. Dwight, John R. Freeman, all members of the deputa- tion; and M. Gaston Liebert, French Consul General; Captain G. H. Armstrong, British Counsel General; G. G. Clapperton, representing the British Institution bf Electrical Engineers, and Prof. Jacques Cavalier, spokesman for the French universities. Among the engineers from other cities was Governor. James Hartness of Vermont.

Jan 1, 1921

By J. H. East, E. R. Maize

INTRODUCTION PROBABLY no other type of equipment is now being introduced into American underground mines about which less is known and about which there is more misinformation than the Diesel mine locomotive. Any equipment installed underground brings with it hazards that were not present before, and it is the purpose of this paper to show that Diesel-powered equipment can be used with safety in underground mining if certain feasible but very important precautions are taken. Diesel locomotives are not new in underground mining, since they have been used successfully in European mines for at least 19 years, but their use in American mines is exceedingly limited; so far as is known, only five Diesel mine locomotives are operating at present in United States mines. Diesel locomotives were permitted underground in Great Britain for the first time in 1939, and the rapid increase in the number in use in those mines, testifies to their safety and efficiency. More than 1300 Diesel mine locomotives are in use in European mines, according to the latest statistics; these locomotives are employed in coal, iron, lead-zinc and mercury mines. So far as is known, the Diesel mine locomotive has not yet caused an explosion or mine fire, and has not been the cause of any fatalities from toxic gases in the mines in which it has been used. ADJUSTMENTS OF DIESEL ENGINES FOR UNDERGROUND USE A Diesel engine adjusted to work in an underground mine should not be confused with the same engine adjusted for use outside the mine. Adjustment of the air:fuel ratio for engines that are used on the surface is intended to give the maximum fuel economy, and little or no attention is given to the chemical composition of the exhaust gas produced. Many such engines are poorly adjusted and perhaps poorly maintained, with the result that the engine emits smoke in quantity as well as the disagreeable odor familiarly associated with Diesel engines. The air:fuel ratio in the case of Diesel engines operated on the surface is generally around 15:1; that is, 15 lb of air to burn 1 lb of fuel. Diesel engines adjusted to work underground usually have an air:fuel ratio of about 20:I, as at this ratio the minimum quantity of toxic gases is given off in the engine exhaust. Diesel engines operated underground must be maintained in better condition than similar engines used on the surface; otherwise, the smoke emitted in the exhaust becomes objectionable if not unendurable. Practically normal air is required for safe operation of Diesel engines underground or in confined places; failure to provide virtually normal air for Diesel engine operation is almost certain to result in trouble. Bureau of Mines engineers have determined that the air in which a Diesel operates in confined places should contain less than 1/2 pct of carbon dioxide and at least 20 pct of

Jan 1, 1947

R. U. Jackson (Conveyor vs. Track Haulage, P. 866) is the author of a previous work on conveyor systems, which was presented at the Annual Meeting of the Arizona Section of the AIME in December 1951. He has worked for the Carnegie Steel Co., Koppers Co., Fairmont Mining Machinery Co., and the Hewitt-Robins, Inc., the Robins Conveyor Div., for the past 30 years, as engineer, district manager, and manager of the mining div. Jackson is a graduate of Carnegie Institute of Technology, and was born in Steelton; Pa. His present residence is in Clifton, N. J., where in his spare time he devotes himself to hiking and photography interests. F. S. White (Co-author, Solids Fluidization Applied to Lime Burning, P. 903) is a Washington University, St. Louis, Graduate, who now lives in Stockbridge, Mass. He served as a technical apprentice at Mobile, Ala., for the Aluminum Ore Co., and after four years went to Bauxite, Ark, as technical superintendent of calcination and precipitation. After a year and a half, he became technical and operating superintendent of the sintering plant. White also worked for the Dorr Co., and is now with the New England Lime Co. serving as assistant to the president. For relaxation he collects stamps and plays the piano.

Jan 1, 1952

By Francois E. Heuze

INTRODUCTION Rock slope stability typically is governed by the geological discontinuities. This stability can be improved by drainage, unloading, adjustment in slope orientation, adjustment in slope angle, and also by reinforcement such as bolts or tendons. This paper addresses the modeling of bolt reinforcement in rock slopes. Most geological discontinuities such as joints have rough surfaces; they dilate during shear displacement. Their shear strength is characterized by two envelopes (Fig. 1); the peak envelope is distinct from the residual envelope when the joints can dilate. If the dilation is restrained transversely, such as with bolts, the normal stress will increase and the joint strength also will increase. It has been demonstrated that this increase may be considerable (Obert et al., 1976). The new normal stress at peak strength is a com- posite function of the properties of the rock mass and of the steel (Heuze, 1979). Hence, the dilation and its resultant effects on joint shear strength must be included in the analysis and design of the reinforcement. We present a model which can be used to perform such an analysis. Early studies of rock reinforcement in mining and civil applications (Lang, 1957 - Panek, 1962 - Osen and Parsons, 1966 - Lang, 19721, did not consider the specific effects of bolts on joint shear strength. In 1973, Heuze and Goodman reported direct shear tests on rough sandstone joints with bolts perpendicular to the joint plane (Fig. 2). The peak shear strength of such joints was greatly in excess of the shear strength of the unbolted joints. The excess

Jan 1, 1983

The term metamorphism as commonly used means any change in a rock in either form or composition, from whatever cause. By metasomatism, according to Lindgren, is meant a metamorphism that involves a change in the chemical composition of a rock by the addition or subtraction of substance. Certain types of metamorphism are due to the action of mineralizing solutions, and are closely connected with ore deposition; they form, therefore, valuable guides in the exploration for ore- deposits. Other types of metamorphism are due to regional processes, and are not connected with ore deposition. By dynamo-regional metamorphism is meant a primary alteration of rocks over large areas under conditions of pressure, flowage, and heat. This process produces schists and gneisses from either sediments or igneous rocks. It is thought that there is little migration of minerals or of elements in dynamo-regional metamorphism, and that the changes are due chiefly to recrystallization and rearrangement of original minerals in bands with their major axes oriented normal to the direction of greatest pressure. Under these conditions limestones are commonly altered to marble, and sandstones to quartzite, basic igneous rocks to greenstone or serpentine, while rocks of normal or acid com- position commonly yield the usual types of schist or gneiss. Dynamo-regional metamorphism, extending over large areas, has no connection with mineralizing processes, and is, therefore, no guide to ore deposits; while this process has certain features, such as characteristic mineral associations, in common with contact metamorphism, the results of the two processes may usually be distinguished without difficulty.

Jan 1, 1932

By Edward L. Vickers

The Pacific rim countries, comprising more than half the globe, represent a complex mix of developed and developing nations. The area comprises a large segment of the industrialized world. Within its boundaries are also found many of the world's greatest mineral resources largely concentrated in the less developed countries. The conflicting objectives of these developed and developing nations are giving rise to changes in the traditional patterns of world resource development. Powerful political and socio-economic factors affecting the world today are having a great bearing on natural resource developments in the Pacific basin. New forms of partnerships have been emerging in developing nations which have had a great impact on the mining com- munity, lending institutions, as well as political relations. The United States and Japan have been substantially responsible in the past for the development of natural resources in this area of the world. Their role, however, is undergoing significant metamorphosis. The rapidly changing economic and social environment in the developing countries is producing new tensions which affect future collaboration between producers and users of natural resources. To understand current problems, I believe, it is worthwhile to examine historical trends in this area which may help defining alternatives facing us in the future. In modern times the United States was the first country in the Pacific basin to start development of resources on a massive scale. It began with the major exploration of the mineral-rich west of the United States and extended significantly later into Latin America and Australia. In the early 1950's, Japan became a significant

Jan 1, 1976

By C Gunther

The term metamorphism as commonly used means any change in a rock in either form or composition, from whatever cause. By metasomatism, according to Lindgren, is meant a metamorphism that involves a change in the chemical composition of a rock by the addition or subtraction of substance. Certain types of metamorphism are due to the action of mineralizing solutions, and are closely connected with ore deposition; they form, therefore, valuable guides in the exploration for ore-deposits. Other types of metamorphism are due to regional processes, and are not connected with ore deposition. By dynamo-regional metamorphism is meant a primary alteration of rocks over large areas under conditions of pressure, flow- age, and heat. This process produces schists and gneisses from either sediments or igneous rocks. It is thought that there is little migration of minerals or of elements in dynamo-regional metamorphism, and that the changes are due chiefly to recrysallization and rearrangement of original minerals in bands with their major axes oriented normal to the direction of greatest pressure. Under these conditions limestones are commonly altered to marble, and sandstones to quartzite, basic igneous rocks to greenstone or serpentine, while rocks of normal or acid com- position commonly yield the usual types of schist or gneiss. Dynamo-regional metamorphism, extending over large areas, has no connection with mineralizing processes, and is, therefore, no guide to ore deposits; while this process has certain features, such as characteristic mineral associations, in common with contact metamorphism, the results of the two processes may usually be distinguished without difficulty.

Jan 1, 1932

THE fall meeting of the Petroleum Division of the American Institute of Mining and Metallurgical Engineers will be held in Fort Worth on Oct. 19 and 20. The Texas Hotel will be headquarters. for this meeting, the technical sessions being held in the ball-room of the hotel. During the evening of the nineteenth a smoker will be held at the Fort Worth Club. In working out the program for this meeting, J. B. Umpleby, vice-chairman for production engineering, considered it especially desirable to offer as complete a discussion as possible of the subject of air-gas lift, its theory and practice, and its relationship to gas-oil ratios. The entire first day will be devoted to sessions on this subject. One session of the second day will be devoted to the use of electricity in oil-field operations and the second to the handling of congealing oils and paraffin. In addition to this program there will be one or more sessions when petroleum engineering research problems will be discussed. This meeting of the Division is primarily devoted to production engineering, as will be seen from the pro-gram. During one of the sessions, however, a brief review with forecasts of the production situation will be presented.

Jan 8, 1927

By J. W. Gwinn

The underground haulage system in the lead-silver mine of the Bunker Hill & Sullivan Co., situated at Kellogg, Idaho, is the most extensive in the Cæur d'Alene district, comprising about 35,000 ft. of tunnels, drifts, and cross-cuts where locomotive haulage is in use. The main working adit, known as the Kellogg tunnel, or No. 9 level, is approximately 10,000 ft. in length from the portal to the main working shaft and extends beyond that about 4,500 ft. in each of two directions. On this level all the ore from the Bunker Hill & Sullivan, the Sierra Nevada Consolidated, and the Caledonia Mining Co.—an average of 44,600 tons per month—is hauled to the mills, located a short distance from the portal. Electric haulage by the trolley-type locomotive is used on this level throughout. Below this level, at intervals of 200 ft. vertically, are five other working levels (Nos. 10, 11,12,13, and 14); and the total haulage distance on these, where electric locomotives are used, is approximately 16,000 ft. No. 13 level has but recently been opened up and is not working to capacity; while the main cross-cut on No. 14 has just been started, and has no need of power haulage. Of the four levels equipped with electric haulage, Nos. 11, 12, and 13 have storage-battery locomotives, and No. 10 still retains the trolley type by reason of the small and decreasing tonnage produced. Electrification - Electric power is supplied to the mine by two systems. The first, the 500-volt direct-current trolley, was installed in 1897 when the Kellogg tunnel was started, and was extended as the tunnel advanced, being used for the first trainload of ore on Nov. 17, 1902, since which time it has been in continuous service. The current for the line is transmitted on a No. 00 copper wire as far as the shaft, and on No. 0 wire throughout the remaining length of the Kellogg tunnel; and until the installation of the storage-battery locomotives it was used in practically all the cross-cuts and drifts on each level below No. 9.

Jan 1, 1915

The Library of the above-named Societies is open from 9 A. M. to 10 P. M. except on holidays. It contains about 70,000 volumes and 90,000 pamphlets, including sets of technical periodicals and publications of scientific and technical societies. Members of the Institute, with few exceptions are forced to spend a portion of their time in localities isolated from sources of information. To these the Library; through its Library Service Bureau, can render valuable service through correspondence; letters requesting information will receive especial attention: The Library is prepared, to furnish references and photographic copies of articles on mining and metallurgical subjects; to determine the existence of mining maps, and to furnish general Information on the geology and mineral resources of-all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. HARRISON W. CRAVER, Director.

Jan 4, 1919

PRELIMINARY REPORT PUBLISHED FOR THE PURPOSE. OF INVITING SUGGESTIONS FOR, THE BENEFIT OF THE COMMITTEE 1 As a result of invitations extended by The American Society of Mechanical Engineers, a, number of associations of national scope have appointed representatives on a Joint. Committee on Standards for Graphic Presentation:- Below are the names of the members of the committee and of the associations which have co-operated in its formation. WILLARD C. BRINTON, Chairman,. American Society of Mechanical Engineers. [7 East 42nd Street, New York City.] LEONARD P. AYRES,Secretary, American Statistical Association. [130 East 22nd Street, New York City.] N. A. CARLE, American Institute of Electrical Engineers. ROBERT E. CHADDOCK, American Association for the Advancement of Science. FREDERICK A. CLEVELAND, American Academy of Political and Social Science. H. E. CRAMPTON, American, Genetic Association. WALTER S. GIFFORD, American Economic Association. J. ARTHUR HARRIS, American Society of Naturalists. H. E. HAWKES, American Mathematical Society. JOSEPH, A. HILL, United States Census Bureau. HENRY D. HUBBARD, United States Bureau of Standards. ROBERT H: MONTGOMERY, American Association of Public Accountants. HENRY H. NORRIS, Society for the Promotion of Engineering Education. ALEXANDER. SMITH,. American Chemical Society. JUDD STEWART, American Institute of Mining Engineers. WENDALL M. STRONG, Actuarial Society of America. EDWARD L. THORNDIKE, American Psychological Association.

Jan 10, 1915

By W. B. Plank

I HAVE been asked by the Chairman of the Engineering Education Committee to outline what the engineering colleges would like the mining companies to do with the young engineer just, out of college. It has been suggested that, because my own personal experience has been almost entirely within the coal industry, I handle this subject from that view- point. Many thoughtful engineering educators are today wondering what effect the present employment policies of many industrial companies are going to have on the young man just starting out in his profession. Since before the World War large industrial concerns, such as those in the electrical and mechanical industries, have gone to the colleges to interview 'likely graduates until today there has developed in most of our engineering colleges, especially in the eastern part of the country, what appears to be a lively competition on the part of these companies in bidding for the young graduate engineer. The employers of mining engineers, with one or two exceptions, have not yet begun to enter this competition. It remains to be seen how serious this situation will become, how it will affect the training of other engineers, and what effect, if any, it will have on the mind of the young man about to enter college who may be inclined to take up mining engineering, but who gains the impression from this well advertised employment service just mentioned that there is no opportunity for him in the mineral industry as com- pared with the opportunities offered in say civil, mechanical, and electrical engineering.

Jan 1, 1929

By Robert F. Mehl

THE solid solutions which aluminum forms with copper, and with magnesium and silicon, are not extensive, and accordingly could not be expected to form Widmanstätten figures profusely nor with great ease. A study of the Widmanstätten figures in these systems seemed desirable, however, because of the interest which these alloys bear towards age-hardening theories resulting from the necessary relationship between the age-hardening phenomena and the atomic processes leading to the formation of Widmanstätten figures.1 ALLOYS OF ALUMINUM WITH COPPER The most accurate determination f the solid solubility, of copper in aluminum seems to be that by Dix and Richardson,2 whose results are represented in Fig. 1. According to this work, aluminum dissolves 5.6 weight per cent of copper at 548°, and less than one per cent at room temperature. Judging from the constitutional diagram, this solid solution on cooling tends to precipitate the compound CuAl2, and this conclusion has been confirmed experimentally by Schmid and Wassermann .3

Jan 1, 1932

By Charles Will Wright

ALTHOUGH the United States has long led all other countries in both the production and consumption of mineral products, the trend seems definitely toward an increasing dependence upon foreign sources of supply. This is not to take the position that we are either a have or a have-not nation. For years we shall continue to secure a large proportion of our needed minerals: from our own mines, but we must face the fact that this century has seen "a more thorough and intense development of the mineral resources of the United States and a greater depletion of its irreplaceable mineral reserves than has occurred in most other countries. An audit of our mineral production given in the attached charts discloses the extent of our deficiencies. Because of these facts, low-cost foreign sources offer a promising field for the investment of a portion of our mining capital and an opportunity to obtain for the United States a greater supply of strategic metals and minerals. How. ever, to reach this end, the industrialist investing in the foreign field must have the full co-operation and strong backing of the Federal Government and the involved Federal agencies.

Jan 1, 1947

By Evan Just

Attempting to analyze a 25-year forecast after less than a third of the time has elapsed may seem premature. The President's Materials Policy Com- mission's report necessarily painted with a broad brush and made no claim for pinpoint accuracy in its predictions. More importantly for present purposes, it made no attempt to predict the detailed courses of production and consumption during the period forecasted. Several statistical highs and lows may very well lie between now and 1957, so comparing recent figures with points taken from the report on a straight-line basis would be illogical. Moreover, the report assumed that the general trend of consumption-domestic and foreign-would be upward. Contrarily, domestic figures were lower in 1957 than in 1950. Therefore, to project curves from 1950 through 1957 leads to conclusions that are probably false. Many in the industry would feel more uncertain about forecasting 1975 domestic conditions now than they would have been in 1950, even though nearly a third of the 25 years has elapsed. In making comparisons, several statistical problems are encountered. The Paley report figures for 1950 were estimated in several cases and corrected figures vary as much as 10 pct. For example, the report placed 1950 lead consumption at 800,000 tons, whereas actual consumption was 885,000 tons. Obviously, in comparing more recent figures with the report's projections, adjustments must be made for positions taken in error from the start. Over the long pull, such discrepancies will probably be insignificant, but they must be noted in comparing short-term changes.

Jan 10, 1959

Jan 1, 1933

By Ali M. Heidarieh Zadeh, Raghu N. Singh

The paper presents a stability investigation of shaft intersections and pit bottom roadways in the vicinity of upcast and downcast shafts at a colliery in the U.K. Aschemeof instrumentation was aimed at monitoring the strata displacement surrounding the pit bottom roadways and shaft intersections with a view to ascertaining the origin of the strata movement and effectiveness of the control measures. The bore- hole instrumentation results together with a theoretical analysis suggested that the cause of instability could be attributed to the drivage of a roadway within the shaft pillar. A semi-empirical technique was used to calculate the amount of support resistance required to reinforce the pillar to take additional abutment load. A rock bolting system was designed to provide a required increase in thrust capacity of the roadway support. The results indicated that roadway closure was effectively controlled after installation of bolts indicating efficacy of the control measures adopted.

Jan 1, 1982

By R. P. Rothwell

THE first difficulty mentioned is that in some instances two or more beds of coal separated by sandstone or slate rocks of considerable thickness in one part of a basin, are found running together in another part. Of course, we may happen to strike first the part of the basin where there is but a single seam, and in this case the bed would appear to divide into two or more branches within a short distance. Such cases are not rare in the anthracite coal-fields. I would suggest as an explanation of this phenomenon the gradual sinking of the peat-marsh-the embryo coal-bed-on one side, and the moving forward of the marsh, so that on one part of the bed the formation of peat would still be progressing, while another part, being under water, would be covered with mud and sand. Thus we have different portions of the same bed of different ages. Now if the sinking of the marsh be stopped for a time, the bed will become thicker in the portions left exposed, and if the sinking now changes in direction, so that the part that had previously gone down com¬mences to rise, we should have the phenomenon of a bed, continuous throughout, with one portion overlying another, and separated from it by rock strata. These are exactly the conditions observed in splitting beds. While one side of the lake is sinking, and the peat-marsh moving on in that direction, the other side may be rising,

Jan 1, 1873

By William Fink

MANY investigators have attempted to determine the true nature of the internal changes taking place during aging. Merica, Waltenberg and Scott1 were the first to propose a theory of age-hardening. They attributed the age-hardening of duralumin to the precipitation of minute particles of the compound CuA12. Later Zay Jeffries and R. S. Archer2 augmented the above theory by suggesting that the small CuA12 particles acted as "keys" causing "slip interference." Many other investi-gators3 have devoted much time to the mechanism of age-hardening, some corroborating the "precipitation" and "slip interference" theory, others coming to different conclusions because of effects that to them seemed unexplainable by the early theories; e.g., the increase of electrical resistance upon aging, the fact that no change in lattice parameter could be detected during the early stages of aging even at elevated tempera-tures, and the fact that the density did not change as would be predicted. In 1932, Merica revised4 his earlier precipitation theory to take care of these presumably anomalous effects. This revised theory, the "knot" theory, assumes that substantial age-hardening occurs before actual precipitation of solute as discrete particles. The assumed mechanism is one of diffusion of solute atones into groups forming distorted regions which act as "hard" spots and cause slip interference. These "knots" are assumed to have approximately the same lattice arrangement as the solvent.

Jan 1, 1936

By Arthur L. Bishop

INTRODUCTION Purpose The in-situ leach method for uranium extraction is a relatively new and innovative method of uranium mining. In 1975, the first commercial in-situ facility began operation in south Texas. Since that time numerous other operations have been initiated as either pilot or commercial ventures. Considerable literature has been published that deals primarily with generalities of the process or environmental concerns. Several federal agencies have published documents which do not reflect the true operating or environmental nature of the in-situ leach method of uranium extraction. From an environmental standpoint, this is also evident in the promulgation of rules and regulations. Hence, the purpose of this paper is to present experience with an environmental concern--non- production zone excursions--such that the industry and the regulatory agencies will gain greater insight devoid of preconceived ideas and misconceptions. General Process Description In south Texas, in-situ leach mining is utilized to extract uranium from permeable sandstone ore deposits 61 to 213 meters (200 to 700 feet) below the surface. Uranium is present as an insoluble uranium oxide. In the in-situ or solution mining technique, anoxidizing lixiviant is injected into the formation through injection wells. The solution reacts with the insol uble carbonate complex. This soluble uranium complex is produced at recovery wells, each containing a submersible pump. During production there is a constant sweeping of lixiviant through the formation from the injection wells to the recovery wells. Injection and recovery wells can be arranged in any of a number of geometric patterns dependent upon ore body configuration, aquifer permeability, and operator preference. Submersible pumps in the recovery wells pump the uranium rich pregnant solution to the initial processing facility. Monitor wells surrcsund the pattern area and are screened in appropriate stratigraphic horizons (production and non-production zones) to detect any lixiviant migration that may occur (Fig. 1).

Jan 1, 1980