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By J. Murray Riddell, Arthur E. Anderson, Grover J. Holt

Out of the depths of each business cycle we emerge with a stimulus for greater efficiency and a realization of progress in industrial technique. The recent years have not been an exception to this rule, and in retrospect we sense that significant advances have been made in mining practices on the Mesabi Range, with emphasis on speed of production and economy of operation. A survey of such changes does not reveal anything that is fundamentally or basically new, but it is apparent that ideas and machines that have found wide application in industry elsewhere, with necessary modifications, are being put to productive use in mining iron ore. Innovations in transporting and conveying ore from the open pits stand out with greatest prominence, so that, in the main, it will be with these features that this paper will treat, in the review of progress made to this date. The late years have witnessed the development of small deposits for open-pit operation, the cleaning up of pits nearing exhaustion, and in two large operations the approach to the limit for haulage by steam locomotives, owing to grades, making it necessary to recover the ore in slopes, track benches and below the power-shovel limit by a milling and scram operation. For several years small standard-type dump trucks have been used in clean-up or scram operations within the pits, but during the season of 1936 the first effort was made to use heavy truck haulage in the transportation of stripping and iron ore. The new units in use today vary from 15 to 20 tons in capacity, and are equipped with powerful gasoline or Diesel engines and supplemented by trailers or wagons on rubber or crawler treads. The Diesel engine finds favor with most operators because of fuel economy. These units develop upward of 125 hp. in the 15-ton trucks. The speed of these trucks varies from 2 miles per hour in Pow gear to 35 in high gear. The transmission affords 12 speeds forward and 3 speeds in reverse.

Jan 1, 1940

By Max Hebgen

I. Natural Features of State Affecting Power Development .. 792 II. Early Developments. 1. Big Hole Plant................. 792 2. Canyon Feny Plant............... 793 3. Madison Plant No. 1............... 593 4. Black Eagle Plant................ 795 III. Later Developments. 1. Madison River System .............. 795 2. Missouri River System.............. 797 3. Great Falls System............... 797 4. Missoula River Development............ 797 5. Big Fork Development.............. 802 $ IV. Present Capacity of Power Developments....... 802 V. Transmission System...............: . 802 VI. Character of Load. 1. Lighting and Small Power Uses........... 804 2. Street Railways ................ 804 3. Mining................... 804 4. Railroads.................... 808 5. Irrigation................... 810 VII. Operation of System................. 812 VIII. Increase in Use of Power............... 811 IX. New Power Developments............... 814 X. Undeveloped Powers................. 815 It is estimated that the total stationary power now used in the United States. steam. water and gas. is probably over 30.000.000 h. p. The total developed water power is about 6.000.000 h. p. The water power in the United States now economically capable of development probably exceeds 25.000.000 h. p. The total developed and undeveloped power is

Jan 1, 1914

By Richard Hamburger

Calculating machines permit the use of the more rapid cotangent and semigraphic solutions of plane triangulation. The results of these methods are as accurate as those of other methods. Simple adjustment of the net, and ease of calculation encourage more complete field work. Errors in field work or in computation are easily localized.

Jan 1, 1950

By Herbert Clark Hoover, Lou Henry Hoover

QUESTIONS of assaying were explained in the last Book, and I have now come to a greater task, that is, to the description of how we extract the metals. First of all I will explain the method of preparing the ore1 ; for since Nature usually creates metals in an impure state, mixed with earth, stones, and solidified juices, it is necessary to separate most of these impurities from the ores as far as can be, before they are smelted, and therefore I will now describe the methods by which the ores are sorted, broken with hammers, burnt, crushed with stamps, ground into powder, sifted, washed, roasted, and calcineda.

Jan 1, 1950

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

By Eugene A. Stephenson

NUMBER of noteworthy events in the petroleum industry may be reported for 1941, of which the most spectacular was doubtless the rise in the daily rate of crude-oil production to a peak of approximately 4,300,000 barrels. This enormous daily rate did not ensue from the furor of flush pools but represented for the most part merely a slight additional daily delivery from many wells that had previously been operated on a more restricted basis, in line with good conservation practice and also from the adroit increase in the number of days per week by the Texas Railroad Commission. Another important fact was the increase in price throughout the Mid-Continent area from the static level of $1.02 for 36°, A.P.I., crude, to $1.17 per barrel. Efforts to elevate the price above this point have met with severe opposition from the O.P.A.. as has also a similar effort by the PennsyIvania Crude Oil Producers' Association, but the vastly increased costs for materials and labor may shortly give the industry the enhanced price which it has long deserved.

Jan 1, 1942

By Kenneth K. Humphreys

INTRODUCTION What is automation? Why automate? Webster's New Collegiate Dictionary defines automation as "the automatically controlled operation of an apparatus, process, or system by mechanical or electronic devices that take the place of human organs of observation, effort, and decision." This definition gives an implied answer to the second question, "Why automate?" Automation, automatic control devices, and process control equipment receive their justification in supplementing or replacing manpower, which results in decreased operating costs. In the past, processes were operated with the minimum amount of instruments needed merely to guide operators. Processes were manually con- trolled by the operator on the basis of simple temperature, pressure, flow, and level indications on a panel. Today the tendency is to design a new plant to operate in a fully automatic manner according to a preset pro- gram utilizing a minimum of manpower. In addition to this direct cost reduction in manual labor, increased equipment capacity results from uniformity of flow and uniform control of process variables. This control eliminates or minimizes surges and permits equipment to be operated at or near its ultimate capacity and, for a given material throughput, permits the use of smaller process equipment. Automatic control, therefore, be it in the field of coal processing or in any industrial field, is simply a problem of economics. Control equipment is justified in terms of its contribution toward increasing productivity, increasing profit margins, or producing a new and salable product at a profit. Instruments and control devices can be divided into two general groups: (1) units which measure and (2) units which both measure and control a process variable.

Jan 1, 1979

By Philip D. Wilson

WHEN the United Nations win the war and the decision has been made to control future armament in the Axis countries, plans for the extent and operation of such control must have been prepared, to be ready to put into immediate execution. Such control to be effective must be premised upon complete military occupation of the two countries for a substantial period, with an arrangement at the end of such occupation for continued supervision of these industries into an indefinite future.

Jan 1, 1944

By T. D. Jones

MUCH the same story can be told for the lead industry for the year 1945 as for the three previous years. In response to inquiries as to new developments, invariably the answer has been, "No new developments-our men either too busy with the man-power problem or trying to get production out." Time and efforts of industry have been concentrated for the most part on war or readjustment problems. Now that V-E and V-1 day have passed, the lead industry can justly be proud of its record in World War II. As in previous wars, lead played an important role and one of its most spectacular uses was in the production of the atomic bomb. We read that the part lead played was rather obscure, but as a protective agent, lead played a most significant role. "Since the materials in the Pile Plant are intensely radioactive, all storage and handling must be done behind thick concrete walls or lead shields. The material is never seen and all operations are auto matically controlled by a foolproof remote control system especially designed for this purpose." (Chews. & Met., Sept. 1945.) When our armies invaded the European theater of war and made a landing on Normandy beach, gasoline and oil for the motive power were furnished through miles of armored lead pipe. This amaz-

Jan 1, 1946

By Bedrand L. Johnson

THE phosphate-rock industry is built upon natural deposits of rocks and minerals in which the element phosphorus is present as a phoshate. The term ?phosphate rock? is a general one, applied to certain rocks of different degrees of consolidation and of diverese origin, charater and occurrence, composed of intimate mixtures of several phosphate minerals, largely submicrocrystalline, usually calcium phosphates, in commerical quantities, with various impurities. This term includes phosphatized limestones, sandstone, shales, and igneous rocks; nodular phosphates ; residual weathered phosphatic limestones ; vein phosphates ; and phosphatic sediments, both consolidated and unconsolidated.

Jan 1, 1944

By Johnston, T. L.

BISMUTH is found as native metal associated with tin, copper, cobalt, silver, gold, or other metals and in a variety of ores. The more important ones are: bismuthinite (bismuth glance), Bi2S3; bismite (bismuth ochre), Bi2O3.3H2O; and bismutite (bismuth carbonate), Bi2O3CO3?H2O. Of lesser importance are the arsenate, telluride, and vanadate. The sulfide is the most common; the others are often oxidation products from this mineral. Bismuth minerals have been found in various places in the United States, principally in Colorado and Utah, but no ores are mined solely for bismuth. In the Granite mining district of Beaver County, Utah, a stratum of limestone about 6 ft. thick has been almost completely replaced by contact minerals in which bismuthinite associated with pyrite and molybdenite was found intergrown with silicate minerals. In the early days a few small lots of ore assaying 7 to 10 per cent bismuth were shipped from this district. Native bismuth has been found in the Clifton and Tintic districts of Utah. Bismuth is produced as a byproduct in the refining of lead, copper, gold and silver ores, it being recovered from the anode mud from the Betts process. Deposits of bismuth minerals exist in Argentina, Aus¬tralia, China, Japan, Germany, Spain, Peru, Bolivia, and Canada, but Bolivia is the principal, producer and could easily supply all of the present world's demand.

Jan 1, 1933

By Frank Harris

THE strength of hard drawn copper wire is a question of considerable importance to both manufacturer and consumer. Unlike steel and alloy wires, in which strength is governed by both chemical and physical considerations, the high conductivity required for copper wire in the electrical industry generally precludes the possibility of obtaining tensile strength through the use of alloys. Consequently, this strength is largely a matter of the physical structure, and all factors known to affect this structure, such as rolling temperature, die contours, lubricants, drawing speeds, etc., are matters of prime importance. The experiments described here have been carried out during the past year at the Baltimore plant of the American Smelting & Refining Co., in connection with a general investigation of some of the questions mentioned above, with the object of studying the physical structure of hard drawn copper, wire and the influence of certain factors on that structure. The work has been of an exploratory nature, rather than comprehensive, but it was thought that the results might prove of sufficient general interest to warrant their publication. The bulk of the hard drawn copper wire used in places where strength is an important factor is manufactured to strict specification, based usually in the United States on that of the American Society for Testing Materials (B-1-23). This specification calls for almost as high a value of tensile strength; consistent with elongation, as it is possible practically to obtain, and only physically perfect material can be relied on to meet such a specification. Obvious defects, such as laminations produced through fins in the original rods or brittleness due to overdrawing, are usually recognized and need only passing reference. Laminations can be detected by twisting and untwisting the wire several times; they will show up on the surface in the form of fins. Fig. 1 shows a very bad example of this defect. The wire may be perfectly smooth before twisting but when such laminations are present they will readily show up under this treatment. This trouble is caused by similar defects in the original rod produced by overfills in rolling. Fig. 2 shows the cross-section of the rod from which the wire in Fig.1 was drawn.

Jan 1, 1928

By L. W. Casteel, E. A. Jones

MINING the lead deposits of Southeast east Missouri has reached a high stage of technical development dictated by the scattered occurrences of low-grade ore through favorable horizons in the Bonne Terre formation. The rock-breaking, handling, and related practices described here have evolved as the best way of mining these particular deposits. These methods are applied in the production of about 19,000 tons of lead ore per operating day from four mines in Southeast Missouri. Development drilling Drifts 10 ft wide and either 8 or 9 ft high are driven in this district on contract. Miners are guaranteed standard wages plus a bonus on the footage advanced, if earned. Labor, fuse, caps, wire, and dynamite used are charged against the contract. Normally the cycle of operations in drifting is performed by a two-man crew, a motor operator and a shovel operator who first load out the rock broken by the preceding shift. The drift crew then sets up two vertical column and mounts the drills. Cleveland HC-10's are used which have a steel lug integral with the cylinder for connection with the air feed. All drilling in drifts is wet. Air pressure is 85 to 100 lb at the face. From 28 to 32 holes are drilled per swing in a pyramid cut. Cut holes

Jan 1, 1947

By W. R. Ingalls

Jan 1, 1922

By W. R. Ingalls

Jan 1, 1922

By F. Keller

SOME PHRASEMAKER has aptly said that nature made aluminum light but research made it strong. Research has been a vital element in the past progress of the aluminum industry and its future growth likewise depends upon the application of the results of research. The role of aluminum products in World War II is well known and this metal will certainly be increasingly important in the postwar world. Some of the principal developments in the war years were in the field of high-strength aluminum alloys. New and stronger alloys were developed which enabled designers to get increased speed and performance in our fighter planes and bombers. The aircraft industry will continue to use these new materials for peacetime passenger and cargo airplanes. High-strength alloys will also find structural applications in trucks, buses, trains, ships, and bridges.

Jan 1, 1946

By JAMES A. VEASEY

SINCE the World War, excepting for a few brief periods of relief, the American petroleum industry has been obliged to meet its important economic responsibility to this nation hampered by the maladjustment that inevitably follows a marked and unwholesome over-production of its raw material, crude oil. Despite the warnings of the Federal Oil Conservation Board and the endeavors of many of the leaders in the business to stem the flow of oil from the wells of the country, the evil ,not only persists but, at the moment, seems more malignant than ever before. Unless the local and temporary restraints on drilling and production now in effect in California, Wyoming, Texas, and Oklahoma are continued, and, indeed, unless stricter and more comprehensive measures of the same sort are imposed and adhered to by the industry in those States, over-production in the enterprise during the current year will be more pronounced than in any other period in history.

Jan 1, 1929

By T. Koulomzine

The theory of the Askania magnetometer, as well as a complete discussion of all factors influencing magnetometer readings, is very ably described by J. Wallace Joyce. We will assume that the reader is thoroughly familiar with this theory and we will use whenever possible the same notations for the physical values involved in the theory. On the other hand, we believe that the principal formulas of the magnetometer can be deduced much more easily by the use of differential calculus than by the methods employed by Joyce. Consequently, we are presenting herewith a resume of the theory of the vertical magnetometer in order to determine the correct formula of the temperature coefficient which we propose to compensate.

Jan 1, 1949

By R. B. Walker, R. Palmer, L. C. Bryner

The purpose of this investigation was to further study some of the factors affecting the air oxidation of sulfide minerals. Data obtained from laboratory studies on the effect of temperature, concentration of iron salts, pH, and other catalysts on the biological and nonbiological oxidation of sulfide minerals are presented. The oxidation of copper sulfide minerals and subsequent leaching of the soluble copper has long been a profitable operation. The chief oxidizing agent is oxygen from the air. This reaction is influenced by a number of different factors such as temperature, light, hydrogen ion concentration, oxidizing agents, and various catalysts. Sullivan1 found that copper sulfide minerals are slowly oxidized by the air and that dilute sulfuric acid and iron (111) increased their solubility. At that time it was not known that bacteria were involved in the oxidation of the sulfide minerals. It has been shown that pyrite, molybdenite, free sulfur, and the copper sulfide minerals found in the waste rock dumps in Bingham Canyon, Utah, are largely oxidized by chemosynthetic autotrophic microorganisms found in the leaching streams.2-6 Similar organisms have been isolated in other mining areas7,8 and from the effluents from coal rnines.9 The following are some of the questions that have arisen regarding the mechanisms of the reactions involved in the leaching process. How dependent is the leaching operation upon the biological reactions? How does the temperature effect the biological and non-biological reactions? How does the concentration of iron (II) and (111) effect the rate of oxidation of copper (II) sulfide? Does the iron act as a catalyst? Does activated carbon act as a catalyst on the oxidation of sulfide minerals? What effect does the hydrogen ion concentration (pH) have on the above reactions? The purpose of this paper is to report the results of laboratory studies on these problems. EXPERIMENTAL The apparatus used in this investigation was an air lift percolator described in our earlier work.' The percolator consisted essentially of an air lift which enabled the leaching solution and microorganisms to pass freely through a suspension of mineral (substrate) in Ottawa sand. The air lift served the additional purpose of maintaining an ample concentration of oxygen and carbon dioxide in the nutrient (leaching) solution. (See Fig. 1.) The percolators were so constructed that they could be immersed in liquid constant temperature baths for temperature studies. The thermostats were controlled to +0.5°C. The reactions were all run in the dark. The percolators were charged with one to three g of mineral, dispersed in 100 g of Ottawa sand and 100 ml of nutrient or leaching solution. The sand was purified to remove traces of iron by digesting with concentrated hydrochloric acid and washng with distilled water until free from chloride. After drying, the sand was ready for use. The compressed air supply was regulated to 5 psi and bubbled through an aerator containing distilled water, which was maintained at the same temperature as the bath used. The air was filtered through cotton plugs to maintain sterile conditions. The tops of the

Jan 1, 1968

By C. F. Willis

The problem of the curtailment of forces in large numbers does not often come to employment departments and is, therefore, a problem that many departments are not prepared to handle intelligently. Those companies that are able to measure the individual efficiency of each man would probably lay off men according to their individual ability, irrespective of dependents, citizenship, or other considerations. During the war when labor was scarce, the business of the employment manager in industry was hiring men and carefully placing them where they were best fitted to work. The careful selection of employees had developed to a considerable extent before the war, and was becoming a recognized science. In the last few months, however, the cancelation of copper contracts, the accumulation of large stocks, the necessary curtailment of production because the copper could not be sold, and the lack of any immediate prospects of' the copper market opening, have led to a universal reduction of forces, and the problem that industry now confronts is that of discharging rather than employing. The problem has been aggravated by the cancellation of contracts in many war industries with the consequent turning loose of hundreds of thousands of men, a great amount of unemployment, and the return of the soldiers and sailors. The problem has now become one of reduction of working force with the least hardship and the least injustice, and yet caring for the soldiers, sailors, and marines who have been in the service of the government for nearly 2 years, and are now returning to their pre-war positions. The Copper Queen Branch of the Phelps Dodge Corpn., operating at Bisbee, Arb., found it necessary, like all of the other copper companies of the country, to reduce its force materially. In making this reduction it was, after due consideration, decided to classify employees with respect to dependents, length of service, and citizenship. The question of individual efficiency or workmanship was not considered. Copper produced to sell at 26 c. a lb. has been selling at under 15 c., and very little copper is being sold at all. Practically every copper producer in the country has enormous stocks on hand, and it would be profitable,

Jan 1, 1920