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By H. l. Burghoff, A. I. Blank

The state of knowledge bearing on the stability of copper under stress at elevated temperatures is generally known to be in need of revision and extension. The present investigation, dealing with the creep characteristics of a deoxidized copper of low residual phosphorus content, is intended to contribute in some small measure toward this end. The experimental data presented herein have been correlated by methods of evaluation and interpretation familiar to those who are concerned with crecp of metals. In practice it is common, if not requisite, to use structurally stable materials at elevated temperatures. It is frequently desirable, however, to test materials under conditions that produce structural change, in order to determine the extent of such change and its effect on physical properties, thus making it possible to establish accurately the limiting conditions to which such materials may be safely exposed. The creep characteristics of the drawn copper wire of this investigation arc directly associated with its structural instability at elevated temperatures. Complete realization of this fact is essential to the evaluation of its creep resistance under various conditions. Creep results should apply to steady deformation under equilibrium conditions, but these are seldom attained in only one or two thousand hours. It will be shown that steady creep rate for copper at useful stresses does not usually begin until considerably more time has elapsed. A wholly satisfactory substitute or shortcut for extensive creep testing does not appear to be evident in the application of mathematical analyses to limited experimental data. Material A single lot of phosphorized copper wire was drawn down to 0.125-i11. diameter with a final reduction of 84 per cent. After mechanical straightening, a portion of this wire was annealed to an average grain size of 0.013 mm. in a controlled-atmosphere furnace. The composition and initial properties of the copper in these two conditions are listed in Table I. Photomicrographs of the original structure are shown in Fig. I.

Jan 1, 1945

By George R. Mansfield

INTEREST in the reserves of phosphate rock in the United States and their proper conservation has recently been aroused by hearings held in different parts of the country by the "Joint Committee to investigate the adequacy and use of phosphate resources of the United States." This committee was appointed within a few days after a Presidential message to Congress on the same subject, dated May 20, 1938, and began to function almost immediately. Hearings were held in Washington, D. C., Pocatello, Ida., Wilson Dam, Ala., Knoxville, Tenn., and Lakeland, Fla. The resulting testimony, when published, comprised a volume of 1182 pages.1 At the earlier hearings held in Washington and Idaho the seeming disparity between the great reserves of the West and the smaller reserves in the East led to some suggestions as to the desirability of curtailing or even prohibiting the exportation of phosphate rock so that eastern producers, becoming alarmed, cooperated in making available for the use of the committee information hitherto closely guarded. This information has provided an opportunity for new studies by official agencies, for a restatement of the reserves of Florida and Tennessee, and for some modification of figures for the Western States. The writer, representing the Federal Geological Survey, was given free access to the Florida material and has prepared for publication a report,2 some features of which are summarized in this paper. The Tennessee material was studied by Dr. G. I. Whitlatch,3 of the Tennessee Division of Geology. Prof. J. Stewart Williams,4 of the Utah State Agricultural College at Logan, has published a recent study of the phosphate resources of Utah and the writer has given some further study to reserves of western phosphate from the viewpoint of including material of lower grade than that hitherto considered. Technologic advances in the phosphate industry must be credited with a large share in the expansion of reserves by making available for

Jan 1, 1940

By Boris J. Kochanowsky, Burke O. Trafton

Because of the strict requirements on the quality of limestone that are dictated by the users, the operator was compelled to find new approaches to produce a product of uniform and acceptable quality. The raw material is controlled and monitored every two minutes by a special computer in order to ensure its quality. The required minimum and maximum quality constraint had an adverse effect on performance and consequently cost. In order to improve this performance, a Monte Carlo simulation model was developed and tested for the optimal truck allocation. The input data is based upon the distribution of equipment performances and costs.

Jan 1, 1969

By Sheldon P. Wimpfen

EVER since the Phoenicians roamed the known world in quest of metals to harden their helmets and precious metals and gems to adorn their ladies, many other nations have sought metals in the far corners of the earth. During the past 75 years American engineers have been among the foremost in seeking for and developing ore deposits. They have been responsible for many of the principal discoveries and for the application of modern methods to mines in the far comers of the earth. American mining engineers with a zest for travel and an insatiable appetite for metals have also introduced throughout the world many articles made of metal which we consider essential to everyday life. Production and consumption of these metals in many foreign countries has brought to these countries an increased standard of living and added tax revenue to their governments. But unfortunately engineers from this country are no longer given ready access to all the countries of the world. This is not only unfortunate for American engineers but also for the countries that have adopted the exclusion policies and especially so since time has proved that in countries where the American engineers have gradually been excluded there has been a significant decline in the progress of the mining industry. Removal of these barriers to professional men would aid immensely in the world-wide development of the mineral industries. New areas brought into production under the guidance of American engineers with their exceptional know-how would provide more jobs for nationals of the countries involved and a better standard of living for the nations as a whole.

Jan 1, 1946

By Michel Elle, John Chipman

The equilibrium of gaseous H20-H2 mixtures with liquid iron-columbium alloys in the range 0.2 to 2.4 pct Cb shows that the activity coefficient of oxygen is strongly diminished by Cb. The oxide in equilibvium with the melt is identified as CbO2. The equi-librium constant at 1600 deg C is [%Cb][fo. % 0]2 = 2.9 x 10-4 where log fo= —0.14 [%Cb]. The deoxidizing power is comparable to that of vanadium, COLUMBIUM (niobium) is finding increasing use as an alloying element in steel. It forms several stable oxides and is removed from the steel bath by oxidizing slags. The specific oxide formed in steel-making is not known although Sazanov snd Shvarts-man,' in their study of its partition between slag and metal, have assumed this to be Cb2O5 It is the purpose of this study to determine its deoxidation equilibrium at 1600°c, the nature of the oxide formed and the interaction between columbium and oxygen in the melt. The investigation was based on the reaction H2 + O=H2O; Kl=ph2o/(pH2[%O]) [1] in which 0 signifies oxygen dissolved in the liquid Fe-Cb alloy. The method and equipment of recent studies2,3 were utilized. In brief, the molten alloy, contained in a small crucible, is held in a controlled mixture of steam, hydrogen, and argon until equilibrium is reached. It is then cooled quickly in a stream of helium and analyzed for columbium and oxygen, the latter by vacuum fusion.4 The solubility of the oxide in liquid iron is determined by visual observation of scum formation on the surface of the melt. Crucibles of MgO proved unsatisfactory because of partial reduction at the metal interface. Pure A12O3 crucibles were heavily blackened by the melt and could not be used at high concentrations of columbium. Silica crucibles were more satisfactory but these introduced some silicon into the melt thus necessitating an uncertain but small correction for its effect on the activities of the other solutes. In silica it was possible to observe the scum formation when the melt became saturated and there was no apparent reaction between scum and crucible. The procedure for saturated melts was as follows. The alloy charge composed of electrolytic iron and columbium grain was melted and held at constant temperature. The gas ratio H2O:H2 was progressively increased by raising the saturator temperature until a point was reached at which a bright film appeared on the surface and covered it completely. This film could be dissolved by raising the temperature of the melt and it reappeared when the temperature was lowered. Under a partial film covering, utilizing bare areas for temperature measurement, the melt was brought to equilibrium with the atmosphere by holding at temperature for about 1 hr as suggested by Dastur.5 INTERACTION IN THE MELT Several experiments were made without columbium to establish a base in silica crucibles. The results are shown in Table I. Except for one run, they agreed well with Floridis1 comparable results in other crucibles. The value of log K1 is taken from Table I as 0.58. This is slightly larger than Floridis' result, probably because of less elaborate safeguards against thermal diffusion. Results obtained in the Fe-Cb-0 series in which no scum formed are shown in Table 11. The equilibrium ratio Kl is defined as ph2o/(ph2[%O]). It is related to the equilibrium constant K1 as follows:

Jan 1, 1962

By Joseph S. Malesky

The discovery and development of explosives mark one of the most important findings in the history of civilization. Without explosives our vast economic enterprise concerning the mining of coal, copper, iron, aluminum, and various other ores could not function. Explosives are used in all kinds of construction works, in the razing of old buildings, blasting of trenches, driving of tunnels, and in many other instances common to our everyday life. For these reasons explosives are rightfully referred to as the forerunner of progress. An explosive may be defined as a substance (usually a mixture) that, when flame or shock is applied, yields readily to rapid combustion or oxidation, accompanied by the formation of such relatively large quantities of gases as to produce much violence and pressure which, in turn, react against their surroundings and cause what is termed an explosion. By their very nature the action of explosives is destructive and disruptive of adjacent materials. Decomposition of explosives can occur through deflagration, which is rapid burning or combustion, as in the case of black powder, or through detonation, which is an almost instantaneous disruption, as in the case of dynamites and blasting agents. HISTORY OF BLASTING WITH EXPLOSIVES At one time workmen obtained stone blocks for building by grooving the rock with crude picks, driving wooden wedges into niches in the rock, and pouring water on the wedges; the swelling of the wood forced out the blocks. As late as the 17th century, fires were placed against the face of rock to crack it, and water was sometimes dashed on the heated rock to shatter it by sudden cooling. The progress of our country is synonymous with advancement of the improved manufacture and extended use of explosives. Coal had been

Jan 1, 1981

By M. J. Pool, P. J. Spencer

Using liquid tin as the solvent metal, the heats of solution of silver and gold in dilute Ag-Au-Sn alloys have been determined at 723°K by solution calorimetry. From the values obtained, the various enthalpy interaction coefficients in the liquid solutions have been calculated. The self-interaction coefficients Au and Ag values of 2413 and -6322 cal per g-atom in binary Au-Sn and Ag-Sn alloys, respectively. For an alloy containing 0.04 mole fraction Ag, Au is equal to 2443 cal per g-atom, and in an alloy containing 0.04 mole fraction Au, Ag has a value of —8883 cal per g-atom. Ag Au has been determined as —2650 cal per g-atom. ADDITION of a second solute to a dilute binary alloy may cause striking changes in the thermodynamic characteristics of the alloy. As yet, such influences cannot be reliably predicted and it is only by accumulation and critical assessment of data that definite patterns can be established. Solute interactions in dilute solutions were first treated mathematically by Wagner,1 who derived expressions for the Gibbs energy interaction coefficients. For an alloy consisting of. two dilute solutes, i and j, in a solvent s, these coefficients are given by: where yi is the activity coefficient of component i and x represents the mole fraction of solute or solvent. Other interaction coefficients have since been established in terms of the various partial molar thermodynamic properties of an alloy; the definitions of these are summarized in a recent paper by Lupis and Elliott.2 Mathematical and experimental studies of such coefficients have received much attention recently, providing a very useful theoretical background to an understanding of the nature of solute interactions taking place in dilute solutions. One of the definitions to arise from such work has been the extension of Wagner's treatment by Lupis and Elliott4 to include an enthalpy interaction coefficient, defined as. where ?Hi is the relative partial molar enthalpy of component i. ?Hi is related to the relative partial molar enthalpy at infinite dilution, ?Hio, and to the enthalpy interaction coefficients by the expression: Values of ?Hi can often be obtained with a high degree of accuracy by calorimetry, and, if the composition of the alloy is carefully controlled by making calculated solute additions throughout a series of measurements, application of Eq. [2] will enable reliable enthalpy interaction coefficients to be determined. Partial heats of solution must be investigated as a function of solute concentrations down to xi = 0, and, since ? values are obtained from the slope of mi plotted against x, great care must be taken to obtain precise data. The data for binary systems which are presently available often require extrapolation of ?Hi values from compositions as great as xi = 0.05 or even 0.1 to obtain limiting heats of solution. Reliable enthalpy interaction coefficients are thus impossible to obtain from published data for most of the alloy systems already investigated. The aim of the present work was to determine values of Au, Ag, Ag, and Au in the limit xsn -1 for the relatively simple Ag-Au-Sn system and from these results to gain some insight into the possible influence

Jan 1, 1969

By Milton E. Wadsworth

The reduction of a metal in an aqueous solution may be defined in terms of its source of electrons. In electrolytic reduction electrons flow as a result of applied voltages. In other systems electron sources are reducing gases or metals of lower electron affinity. In the latter two cases it is increasingly evident that reduction is electro-chemical in nature in that electrons flow through one or more conducting phases even though the discharge reactions may not be rate controlling. Electrode processes impmtant in reduction and metal deposition are reviewed and extended to contact reduction by precipitation (cementation) on mme electropositive metals. Contact reduc- tion Processes are ancient in origin and represent techniques which have had successful application for hundreds of years. In spite of this, little has been understood in terms of the dynamic properties of such systems or of important side reactions. In recent years an increasing amount of laboratory work has been carried out on contact reduction and an attempt is made here to summarize the important findings. Undoubtedly the interest aroused recently may be attributed to improved reactor design which has demonstrated on a commercial basis accelerated metal recovery by taking advantage of important kinetic and chemical parameters. of gold cyanide (Au(CN)-), respectively. The most common method for the reduction of ions in solution is by electrolysis. The impure metal is made the anode and the ions are reduced at the cathode. Leach liquors containing reducible ions may similarly be reduced electrolytically using an inert anode. The latter process is referred to as electrowinning. In recent years hydrogen has been used successfully as a gaseous re-Metallurgical Society of the American Institute of Mining, Metallurgical and Petroleum Engineers (AIME). He was also a member of the Executive Board of the Metallurgical Society (AIME). In 1957 Dr. WADSWORTH was given the AlME Best Paper Award as coauthor of a paper on the roasting of sphalerite. On July 1, 1968 Dr. WADS-WORTH started an 24 month assignment in the Philippine Islands to assist in the development of graduate metallurgical engineering at the University of the Philippines. In addition to graduate teaching and curriculum development he will establish research programs to develop extraction processes for metals production in the islands. The project is supported by the Ford Foundation through Educational Projects, Incorporated.

Jan 1, 1970

By F. William Bloecher, William B. Plank

CURRENTLY 12,892 students are enrolled in the mineral engineering schools of the United States and Canada, marking an all-time record high for these schools. It shows a remarkably rapid recovery from the effects of World War II. Enrollment in all the other engineering branches has also increased but not so rapidly as in the mineral engineering branch. Almost all the data in this report are from the eighth questionnaire study of the mineral engineering schools made, as formerly, under the auspices of the Mineral Industry Education Division of the AIME. Every school is represented in the data, for which the authors thank the deans and professors who supplied the information. For this reason, the data of all the studies are comparable, an achievement not always possible in endeavors of this kind. For comparison with the general engineering enrollment situation, data are included from the January 1947 issue of the Journal of Engineering Education.

Jan 1, 1947

By D. K. Crampton

INTERNAL stress and season cracking in brass have been studied for many years and the technical literature contains many data on various phases of the subject. A résumé of the literature shows certain fairly well established points upon which various authors are mostly agreed: 1. Season cracking is primarily caused by the presence of relatively high internal stresses, or possibly in some cases by external stresses, or both. 2. A specific corrosion is also essential to season cracking: Certain agents, particularly mercurous salts, mercuric salts and ammonia salts; have such a specific corrosive effect. 3. The tendency to season crack under given conditions increases with increasing zinc content, brass containing less than 20 per cent zinc being relatively immune. 4. In alpha brass the season cracks are intercrystalline; in alphabeta brass they lie between the two constituents; and in beta brass they are transcrystalline. 5. The ordinary impurities or added elements in special brasses have little or no effect on the tendency to season crack. 6. Internal stresses can be eliminated, or at least reduced to a safe 'limit by annealing treatments at temperatures that do not produce visible microstructural changes or appreciable softening of the worked brasses. There are, however, some points in connection with the phenomenon of season cracking which have not been thoroughly investigated, or wherein different authors and investigators are not entirely in agreement. The investigations described in this paper were undertaken to determine: 1. The correlation between mercurous nitrate tests and actual season cracking on long-time atmospheric exposure. 2. The quantitative effect of type and degree of drawing operations on the intensity of internal stress and on the tendency to season crack in brass tubes. 3. The possibility of drawing high-brass tubes in such a manner as to prevent the occurrence of harmful stresses rather than to find a remedy for such stresses once having obtained them.

Jan 1, 1930

By Burt C. Mariacher

Extraction of uranium from ores is being accomplished by processes which, for the most part, subject the entire ore to acid or carbonate leaching. Ore deposits with a U3O8 content below 0.10 pct U3O8 are seldom considered suitable for treatment by leaching. A preliminary concentration that would enrich the uranium content of an ore by a simple, low cost process based on physical properties of the ore might result in some low grade deposits becoming commercial ores. In addition, the process might be employed in existing operations to reduce transportation and leaching costs and to increase capacity of existing leaching plants.

Oct 1, 1956

By A. H. Tousley, C. L. Vickers

The author presents a history of the development of the Port of Long Beach from its beginning in 1905 to the present construction of a new bulk loading facility. In describing this new facility, emphasis is placed on such aspects as rail car and truck handling, gravity yard, rotary car dumping, bottom dumping, car dumping equipment, feeding and conveying, ship-loader-stockpiler, stockpiling and reclaim, dust control, and construction problems. Development of the Port of Long Beach, Calif. (see Fig. I), began in 1905. In that year private Long Beach interests acquired 800 acres of marshland in the Inner Harbor area and initiated a program of channel dredging and land reclamation. Efforts to establish a municipal port began a short time later and culminated in the opening of Pier 1 in 1911. An event of even greater significance to the port future also occurred in 1911. This was the tideland grant enactment by the state legislature that conveyed to the city of Long Beach all of the state's rights in the tidelands located within the city boundaries. The grant stipulated that all revenue produced from the tidelands be used for the development of navigation, commerce, and fisheries. During the next 15 years up to 1926, the port's commercial growth was steady, although relatively slow. During this period, several fundamental steps in the development of a major harbor were accomplished. These included the creation of the Board of Harbor Commissioners in 1917, the dredging of the Inner Harbor and entrance channel to accommodate deep draft vessels, and the correction of a serious silting problem through construction of the Los Angeles River Flood Control Channel. These efforts bore fruit during the ensuing 10 years in the establishment of more than $30,000,000 worth of industrial plants and private marine terminals in the Inner Harbor. Commerce over municipal wharves also increased more rapidly, and it became necessary to start the development of the harbor in a seaward direction. In 1936, oil was discovered in the harbor area, and the first Harbor Dept. well was brought in 2 years later. It soon became evident that the city of Long Beach would receive substantial revenue that, under the terms of the state grant of 1911, must be used in the development of the port. It was further realized that to properly guide and coordinate such development, a long range comprehensive plan was essential. The Board of Harbor Commissions contracted with G. F. Nicholson and J. F. Collins, consulting engineers, for the preparation of such a report that was completed in 1940. The Nicholson-Collins report proposed the development of an East Basin, between the entrance channel and the Los Angeles River, and a West Basin in the area now occupied by the Long Beach Naval Shipyard. Twenty full-size berths were to be provided in the East Basin and more than fifty berths in the West Basin. The report recommended extensive modern terminal facilities for handling waterborne cargo. Attention was given to improvement of the street and highway system to give better vehicular access and to avoid congestion within the port. To a large extent the recommendations of the Nicholson-Collins report were followed in the subsequent development of the East Basin. This development was greatly accelerated by World War 11, with its need for increased oil production and additional shipping facilities. The wartime and immediate postwar construction was largely concentrated on Pier A, with the development of Piers B, C and D following in more recent years. An important factor in the planning of these piers was their dual function as oil drilling sites and cargo piers. The Navy's acquisition of the West Basin area made it necessary to depart from the Nicholson-Collins plan and find other areas for future expansion. At the present time only one Inner Harbor Port-owned area having protected deep water frontage remains undeveloped. This is the property fronting on Channel 2 in the Inner Harbor acquired in December 1957, from Pacific Dock and Terminal Co. The growth of the port has been in a southerly direction since the construction of the Long Beach Naval Shipyard in the West Basin area. Recent extension of Piers F, G and J into the ocean follows typical port construction methods developed during the expansion of the Middle Harbor during the last 20 years.

Jan 1, 1963

By AIME AIME

ON May 5, the Washington, D. C., Section, A.I.M.E., devoted its meeting to the many-sided and perplexing question of mineral stock-piling for peace. Opening the symposium, Harry J. Wolf, of the War Production Board, outlined the problem under six heads: (1) Technical. Mechanical, chemical, or metallurgical importance of specified materials, emergencies that might arise, relative scarcity, and critical value of stock piles during emergencies. (2) Economic. Cost to Government, influence of Government stocks on commercial relationships and markets, effect of availability of items as a con¬structive influence on industry, Administration policies now and during postwar period. (3) Legislative. Need for immediate legislative action, need for legislation on postwar conditions as well as on current requirements, a constructive basic policy to prevent political manipulation. (4) Military. Consideration of re¬quirements and supplies bearing on national safety and needed for manufacture of equipment, and adequate reserves of scarce materials for research or experimentation by military agencies. (5) International. Interests of the United Nations in contradistinction to those of the United States; effects of nonisolation policy on nature, location, and administration of stock piles. (6) Negative stock-piling. Question of United Nations' legislation to prevent stock-piling by Axis nations after the war and who shall purchase stock-pile materials and during what periods.

Jan 1, 1943

By AIME AIME

ON JULY 12, 1921, S. S. Arentz, representative at large from Nevada, introduced in the House of Representatives, under the number H. R. 7736, a bill to revise, amend and codify laws of the United States relating to the location of mining claims on public domain, and other purposes. This bill had been drafted by a committee of consulting engineers of the U. S. Bureau of Mines. The immediate purpose of this introduction in Congress was to make it avail- able for general information and discussion. In pursuance of this purpose Mr. Arentz issued the following circular: This proposed codification and revision of the mining laws of the United States as received from a committee of mining and metallurgical engineers appointed by the Director of the United States Bureau of Mines was introduced in the House of Representatives by the undersigned (who has operated and developed mines throughout the West for many years). It is submitted to prospectors, mine operators and mining engineers, all of whom are affected and vitally interested in the subject with the hope that they will give this bill their careful consideration and study.

Jan 1, 1921

By George W. Pawel

OWING largely to its value as a toughener and strengthener of steel for both industrial and military purposes, nickel is playing, an important role in the current war. It is fine of the metals in which the Allies enjoy a definite edge over the Axis nations and this time there is no place to which the Germans may send another submarine "Deutsehland" and expect to pick up a cargo of nickel to replenish their exhausted supplies. Total world nickel production thanks almost entirely to the expanded operation of the International Nickel Co. of Canada at Sudbury must now be at the rate of around 175,000 tons a year scarcely more than 5 per cent of which is accounted for by Germany, Italy and Japan. This represents more than four times the world output at the end of the first World War.

Jan 1, 1943

[Appalachian Petroleum Section: Walter H. Chapman, chairman; Jean Freeland, first vice-chairman; John Galpin, second vice-chairman; Jack L. Trittipo, secretary-treasurer. Meets 4th Tues., Humphreys Restaurant, Charleston. Balcones Section: William E. Richards, chairman; William C. Miller, Jr., first vice-chairman; Brantley G. Myers, second vice-chairman; Harold Vagtborg, Jr., secretary-treasurer. Meets 4th Wed., Petroleum Center Club, San Antonio. Big Horn Basin Subsection: Donald G. Davis, chairman; B. E. Yester, vice-chairman; J. F. Keleher, vice-chairman; Samuel N. Conley, third vice-chairman; William O. Snyder, secretary; M. J. England, treasurer. Billings Petroleum Section: N. J. Matthews, chairman; Guy J. Lookabaugh, first vice-chairman; George O. Ellis, second vice-chairman; Robert L. Spottswood, secretary-treasurer. Meets 3rd Tues., Turf Penthouse.]

Jan 1, 1961

By Roger K. Clifford, Gary W. Hudiburgh

The amine flotation of feldspar from a magnetite concentrate produced at a domestic concentrator was investigated using zeta potential measurements, Hallimond tube flotation tests, and laboratory-scale flotation tests. The point of zero charge of six feldspars (microcline, orthoclase, albite, anorthite, anorthoclase, and oligoclase) range from pH 1.4 to 2.5. Hallimond tube flotation tests using amine flotation reagents were performed on these feldspars and on gangue material (quartz, albite, and microcline) from the magnetite concentrating plant. Laboratory-scale (623 g and 2500 g) flotation tests were performed on the magnetite concentrate to float the feldspar. The effects of three different collectors, two levels of collector concentration, three pH levels, starch, HF acid and regrind were investigated.

Jan 1, 1977

By Nagel, Theodore

USE of oxygen in metallurgical operations was investigated by a committee of unusually able engineers more than ten years ago. A record of their work appeared under the title "The Use of Oxygen or Oxygenated Air in Metallurgical and Allied Processes," Serial 2502, Report of Investigations, U. S. Bureau of Mines. Shortly thereafter the A.I.M.E. published "Use of Oxygenated Air in Metallurgical Operations," based on a symposium at the New York meeting, February 1, 924. Quoting from the Bureau of Mines report In view of the many recent developments in oxygen manufacture, and considering the increasing cost and decreasing quality of our raw materials, the Bureau of Mines has taken the matter of the application of oxygen or oxygenated air to the metallurgical centers for consideration and has appointed an advisory committee to study the problem.

Jan 1, 1935

By PHILIP N. MOORE

PHILIP NORTH MOORE was born on July 8, 1849, at Connersville, Ind. His father, a civil engineer, was descended from Henry Moore who came from Ireland in 1773 to live in Washington, Pa. Through his mother, Philip Moore was descended from John North, who came to America in 1635 and settled in Connecticut. The story of Mr. Moore's life as told by himself is given on pages 373-386 of T. A. Rickard's "Interviews with Mining Engineers." He studied at Miami University, where he gained the degree of A.B. in 1870, and A.M. in 1873. In 1920 his alma muter conferred on him the honorary degree of LL.D. He, as a special student, was a member of the class of 1872 at the School of Mines of Columbia University.

Jan 1, 1930

For handling rough rock, the shovel-train system is unexcelled. The ideal application is a physically large, but not excessively deep, open-pit mine from which the coarsely blasted ore and waste must be transported distances in excess of three miles. If, in addition, a high production rate is to be maintained, railroad haulage will probably afford a lower cost per ton transportation than will any other haulage method. Relatively gentle grades must be employed- usually 3% for uphill hauls and 4% for downhill hauls. The greater the differences in elevation the greater are the railroad track grade space requirements. By way of illustration, a 3% ramp out of a pit only 300 ft deep must be almost two miles long. Mainline track locations should be selected carefully so that the frequency of movements during the life of the mining operation is minimized. This applies both to ore and to waste haulageways. Such moves are not only expensive but difficult to execute without adversely affecting production rates. The large mine affords greater opportunities for judicious location of semi-permanent trackage.

Jan 10, 1967