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By George A. Lamb

Forecasters, in estimating long-term energy requirements and supplies, have predicted a bright outlook for coal. Some predictions have annual coal output reaching 800 million tons by 1980, almost twice the average of the last five years. These projections assume that ultimate consumer energy products will be supplied adequately not only in volume but also by kind and type. The consumer energy schedule shifts continually as it reflects the changing demands for numerous uses. Its appearance, expressed generally in proportions of solids, liquids, gases and electricity, is quite different today from what it was in 1940. It may change even more by 1980. Thus, the shares that coal and the other energy sources will have In total supply will depend upon how well each source can be processed into products that will be accepted by consumers.

Jan 7, 1963

By Earl C. Willis

In selecting new or replacement mining machinery to be purchased, there are many considerations to be discussed and taken into account, the most important being the productivity of the machine and the maintenance cost and downtime to be expected with the new equipment. Productivity of a given mining machine is evaluated by the Industrial Engineering Department: analysis of potential upkeep and downtime calls for the Maintenance Department to enter into the task of evaluating new mining machines. This is a very important function of the maintenance department because a wrong decision or mistake in judgment, particularly in a commercial mining company, can be exceedingly expensive. Once the type and size of a machine is decided, an examination of units fitting the basic requirements will sometimes show one particular machine which has a distinct edge on the competitive machine. In this case, the decision is easy. However, in most cases, the performances of the machines being considered are so close that the decision becomes one that is very difficult to make on performance alone. Serious consideration must then be given to maintenance performances and features of the machine which would permit lower maintenance and less downtime.

Jan 7, 1963

By John V. Beall

On the banks of Huzzah Creek there is a roadhouse where a group of Ozark folks were whiling away a Sunday afternoon last spring. "How about some of that 'Who Broke the Lock Off the Hen House Door,' " suggested Spinny. The old man obligingly picked up the fiddle and began the sprightly tune. His long, seamed face had ruddy cheeks and a grey stubble jaw. A thick fedora was pushed back off his scraggly hair and he wore a heavy jacket. It was 73 degrees fetchin up for 75 on that May afternoon, so naturally he sweated. The Ozark is fiddling country. The natives, to whom a half dollar looks as big as a manhole cover, put great store by fiddling, along with the other fine things of life such as fishing and horse raising. On the wooded hills, 1200 to 1700 ft above sea level, there are numerous tumbling streams with plump fish, and in clearings along the roller coaster roads are long-legged, frisky looking horses. People in the Ozarks have a reputation for self-reliance. However, they are cheery and friendly to strangers. Trespassers are very seldom shot at-except if they do something wrong or by accident.

Jan 7, 1963

With over one year experience, Western Deep Levels Ltd., reports satisfactory operation with new features of its 200,000 ton per month gold reduction plant. Western Deep is Anglo American group's newest gold mine. It is situated 43 miles west of Johannesburg on the West Wits Line and will ultimately be extracting ore from a depth of 13,000 ft. Although the plant was put in production in March 1962, after a three month break-in period, construction of the fifth milling section was not completed until last month.

Jan 7, 1963

By Richard D. Snouffer

Prime topics of conversation these days are the new concepts of rail haulage for bulk items such as iron ore, potash and coal. We have heard such ideas as the "integral train" and the "unit train" discussed frequently during the past two years at various AIME meetings, and progress reports have kept up a steady appearance in the technical press and in local newspapers. While no railroad has a complete "unit train" in service at this moment, one has 50 fast-discharge cars under construction and the Pennsylvania Railroad has experimented with radio-controlled motive power distributed at intervals throughout the train. To a great extent, however, the promise for greater efficiency and lower costs held out to industry by these new haulage methods is dependent not on greater speed or larger cars or more dedicated equipment alone but, rather, on the utilization of modern practices in the loading and unloading of rail cars. It is the purpose here to examine these two key steps and the up-to-date procedures and equipment they entail.

Jan 7, 1963

MINING ENGINEERING presents the annual membership report of the Society of Mining Engineers; see page 109.

Jan 7, 1963

By Manfred Schmellenkamp

During the lust half-dozen years, longwall mining has taken on a new look, much of which is due to the introduction of self-advancing roof supports from Europe. Here is a report on two longwall operations, one which started up in 1956, the other in 1962. It is a story of manually set, friction- type props us, the new European type; the story of an 18-ton per man-shift operation us one of 50 tons per man-shift.

Jan 6, 1963

By Edmund E. Getzin

Of all the developments in the post-war history of Western Europe, none has been more remarkable in its aims and in the progress it has achieved than the movement toward European integration. It is not an exaggeration to say that this movement marks a virtual revolution, an about-face, in the long and complicated history of European states over the past three centuries. Although sporadic efforts to achieve European integration can be traced back for at least a 100 years, it remained for the breakdown of the European economies as a result of World War II and the subsequent Russian threat to give new impetus to the concept of broader economic and political integration. In fact, the economic integration of Europe following the end of the war was considered so essential that, in 1949, the administrator of the European Cooperation Administration, Paul Hoffman, spoke of the economic integration of Western Europe as an objective of American policy embodied in the Marshall Plan.

Jan 6, 1963

By J. S. Smart

The six countries which make up the European Economic Community-Belgium, France, German Federal Republic, Italy, Luxembourg and The Netherlands-are populated by about 170 million consumers. Their economic abilities and their standard of living have increased at a high rate during the past few years. Consequently, the policies and trade practices adopted by the group will have International repercussions within the nonferrous Industry whether or not other nations are eventually admitted to the group. Considering the hopeful prospects of only a few months ago, it is surprising that we must now face up to the fact that Great Britain and Norway, in particular, will achieve membership status only after prolonged and difficult negotiations, if at all. However, this is but one of many factors that should remind us that the Common Market is yet in its formative stage and has by no means reached maturity.

Jan 6, 1963

By Leonid Bryner

For many years, geologists have inferred a connection between the evolution of the earth's crust and ore deposition, a connection coming under the heading of metallogeny. In recent years the concept of metallogeny has assumed major importance in the exploration planning of Russian geologists in their quest for new mineral sources. As defined by Radkevich, metallogeny is "the science which studies the laws governing the distribution of ore deposits in the earth's crust." However, since it can be argued that metallogeny does not contain enough certitude to be classified as a "science," it would be more appropriately defined as the study of metallogenic provinces, and metallogenic epochs.

Jan 6, 1963

By Joseph A. Sutton, John D. Corrick

The continuing depletion of high-grade ore de- posits in this country has created a need to develop more effective methods for recovering valuable metals from low-grade ores. The use of microorganisms for their biochemical reactions is one possible way to solve certain phases of this problem. Bacteria have been used successfully by many diversified industries. Until recently, however, little attention has been focused on the use of bacteria in mining and metallurgical processes. This report summarizes one phase of the microbial studies being conducted at the U.S. Bureau of Mines, College Park Metallurgy Research Center. The two-fold objective of this study was, first, to determine if pure strains of the bacteria Ferrobacillus ferrooxidans, Thiobacillus concretivorus and Thiobacillus ferrooxidans could utilize the iron and sulfur occurring in sulfide minerals to produce appreciable quantities of ferric sulfate and sulfuric acid for dissolving copper and, second, to develop the chemistry involved in the microbial oxidation of sulfide minerals. These are of particular interest as they relate directly to the feasibility of employing microorganisms in leaching operations.

Jan 6, 1963

A completely automated primary crusher is now in operation at Kaiser Steel Corp.'s Eagle Mountain, Calif., iron mine. The word "completely" is italicized to underscore its literal meaning- automation so thorough that even the control room for the crusher does not require a man to watch the flickering dials and lights. The automation of the unit is such that its operation, including starting and stopping, are controlled from the secondary crusher station. The crusher-a Symons 60-in. gyratory which can handle 3600 tph-features built-in safety devices that will turn the crusher off if oil pressure drops, if oil overheats, if bearing temperatures exceed permissible limits, or if parts of its electronic brain fail. According to reports, the worst that can now happen is a plugging of the crusher.

Jan 6, 1963

By Allan B. Bowman

Several years ago a wealthy Chinese business friend of mine purchased an interest in a pro- posed oil well to be drilled a great distance from his home. A few months later it came in as a producer and proved to be a huge success and materially added to his resources. I asked him why a man of his wealth should be so lucky in a venture outside his sphere of knowledge when most people of modest means never seemed to get ahead. His answer was, "Fat Hoy takes a chance." Even though this was his answer, I knew from my association with him that there were other tempering considerations which Mr. Hoy applied before making up his mind to enter any transaction. First, he was a cautious individual. He was also a great believer in details and insisted on knowing everything possible about a situation, and finally, he was what we call a very solid individual with good basic instincts and judgment. This philosophy of Mr. Hoy may be applied to most any business but especially to those engaged in a search for natural resources such as mining where great risks are involved. This article concerns events in the history and growth of Banner Mining Co., with which I have been associated for 27 years in capacities from mine surveyor to vice president. Mr. Hoy's philosophy has played a significant role in the exploration projects of this company over the years, but what is more important, the officers, directors, and controlling interests in Banner have been aggressive in their search for ore reserves.

Jan 6, 1963

By Fred C. Bond

It sometimes happens that old knowledge is forgotten, or half-forgotten, and its rediscovery is hailed as a great new advance in technology. Autogenous grinding affords such an example. The oldest-or apparently the oldest-commercial application of continuous autogenous grinding on a large scale outside of South Africa occurred at San Juancito, Honduras, where a total of more than two million tons of silver ore were ground autogenously with complete success from 1918 to the early 1940's. The history of the San Juancito silver deposits begins in 1880 when- the New York and Honduras Rosario Mining Co. started mining silver at a rate which soon reached two million ounces of silver annually. In 1912 the Company's first mill, located in the village of San Juancito, was shut down and its equipment transferred to a new cyanide plant. This plant, constructed on a mountainside near the mine, was equipped with tube pebble mills in which Normandy or Danish pebbles were used initially.

Jan 5, 1963

By James F. McDivitt

The mineral industry of today is faced with a number of dilemmas, not the least of which grows out of the series of related facts-world mineral consumption is growing, and is expected to continue to grow; maintaining adequate capacity to meet needs will require very great capital investment over the next decades, investment which must be measured in billions of dollars; much of the new production must come from remote and relatively underdeveloped countries; many of the areas in which such development must take place are not areas in which private capital enters without some trepidation. There are real problems in financing new mineral development-problems which have occupied the thoughts of many in the industry. One group which is currently providing part of the answer, and perhaps pointing the way to further progress in the future, is the World Bank. Loans from the World Bank are arranged usually for countries which are attempting to develop their economies through expanded industrial production. More often than not they are for the development of electric power projects or transportation facilities. Although we consider the mineral industries to be basic factors in industrial development and very important factors in the early stages of development of a country, few of these loans are for mineral development-no more than a half dozen out of a total of well over 300 loans which have been granted to date. Yet the World Bank has played a far more important part in world mineral development than these figures would indicate. The few loans for mineral development which it has made are important, but of considerably greater importance are the secondary effects of many of the non-mineral development loans and some of the special services which the Bank also offers.

Jan 5, 1963

At the eastern end of the Mesabi Range, 70 miles due north of Duluth, is the vast plant of Erie Mining Co. Operated by Pickands Mather G Co. for the mine's four owners-Bethlehem Steel, Youngstown Sheet and Tube, Inter- lake Iron, and Steel Co. of Canada-Erie Mining Co, has earned just fame as a pioneer and a leader in the mining, beneficiation, and agglomeration of the lean iron ores of the Lake Superior district. Here is the story of Erie and the integrated operations that have made it such an outstanding member of America's iron ore industry.

Jan 5, 1963

By Frank M. Howell, Claude E. Schmidt

To counteract the spiralling costs of labor and materials against the fixed sale of its product, namely, gold at $35 per oz, Homestake Mining Co. has revised the milling flowsheet once and effected increases in the daily milling rate twice in the past 12 years. During this period the mining department has been able to hold production costs steady by increased productivity through technical improvements and utilization of the most modern mining by CLAUDE E. SCHMIDT and FRANK M. HOWELL, JR. 46-MINING ENGINEERING, APRIL 1963 equipment. The flowsheet alteration occurred during 1951-1953 when the two crushing plants at the shaft head frames were converted to a three-stage crushing system with the third stage closed circuited to produce a minus 5/8-in. product as rod mill feed.

Jan 4, 1963

By D. M. Jamieson, M. P. Pearse, E. R. A. Plumstead

In 1948 the shaft sinking record in the Republic of South Africa was held by the Van Dyk Consolidated Mines Ltd. for a ventilation shaft with a footage of 461 ft sunk during the month of August 1941. This record remained for some ten years; but in the ensuing nine years it was broken no less than 13 times. Table I gives shaft sinking records throughout the world for the 21 years, 1940 to 1960. History shows that the wide, deep, timbered rectangular shaft had passed its peak of popularity by 1948, although it still had a great deal to commend it, both from the sinking and operational points of view. In sinking, it is easy to clean manually, and water can be handled by bailing when wet ground has to be negotiated; its shape also lends itself to equipping concurrently with sinking. In operation it provides the most convenient "in line" hoisting arrangement, and if the ventilation requirements so demand, it offers the simplest solution in that it can be divided into upcast and downcast sections. Furthermore, in the case of a multi-level mine, the shaft compartments can be reduced conveniently if the full area of the shaft is not required to serve all levels.

Jan 4, 1963

By U. K. Custred

To the layman, the term "strip mining" usually applies to the appearance of mined-over land after an operation is completed, not to the technique. This attitude, however, is becoming pass6 in the central Florida pebble phosphate field as eight mining companies in the area pursue a mutual program of land reclamation. The Florida phosphate industry is fortunate in this respect because it occupies an area favorable to reclamation. The terrain is flat; overburden is sand and clay which will support vegetation fairly readily; a high ground water table naturally converts mine pits into lakes. Too, this is water which readily supports marine life, not the acidic water so frequently found in the coal industry.

Jan 4, 1963

By Henry H. Thomas

In Tasmania a tailrace tunnel to handle water discharged from a turbine generator has been successfully driven by a machine tunneling method similar to that described in the July 1962 issue of Civil Engineering. The Hydro-Electric Commission, Tasmania, is constructing a high- head (2750 ft) power project that will utilize the storage in the Great Lake (1,150,000 acre-ft) at an elevation of 3380 ft. The underground power station will house six vertical shaft turbo-generators, each rated at 50,000 kw. The tailrace tunnel, 16 ft diam and 14,600 ft long, was driven through a reasonably homogeneous hard mudstone. It was decided to excavate this mechanically in the hope of saving some money on excavation and a considerable sum on the ultimate lining of the tunnel. Mechanical engineers from Tasmania worked with the firm of James S. Robbins and Associates of Seattle, Wash., which designed and supplied the "mole."

Jan 4, 1963