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By Arthur Young

UNEMPLOYMENT no longer finds its cure in pros-perity. Not only is there surplus labor in over-developed industries -like coal -mining, but more and more man, power is being released by technical im-provements in production. A new problem in industry has arisen: What is to be done with the labor dis-pensed with by better methods and more highly de-veloped equipment? Are luxury industries the logical outlet for our new unemployed? There has been a marked decline in employment in the manufacturing industries during 1927. Its extent is shown by the Bureau of Labor Statistics index, which receded from a high of 91.4 in March to 87.3 in October, with an estimated figure of approximately 85 in De-cember. This was a drop between the high and low points in the year of about 7 per cent, which means roughly that at the close of 1927 there were approxi-mately 600,000 fewer persons employed in manufac-turing industries than in March -of 1927, and upward of 400,000 less than in December, 1926. Does this de-cline reflect a swing toward industrial depression? Paradoxically it does not; the cause of unemployment at this time does not lie in a lack of prosperity, but rather is largely traceable to prosperity. Capital has been abundant and has gone back into production in the form of great increases in mechanization and new processing. Management is more than ever on the alert to improve methods, as well as to cut costs through reduction of personnel. Properly applied incentives and employee cooperation also have increased produc-tion per man. A new phenomenon in the industrial world-technological unemployment-is the result. Of course, there are added to those unemployed be-cause of the reasons just considered those affected by the coal strike, the period of shutdown at the Ford plants, and the reduction in expenditures by railroads and public utilities. This whole situation suggests that the problem of unemployment is not entirely solved by ironing out seasonal variations or by achieving business prosperity.

Jan 1, 1928

By Edel Moldenke

BURMA has long been known for its ruby, tungsten, and tin deposits, and, lately, for having the largest lead-zinc mine in the world, the Bawdwin Mine of the Burma Corpn. All the coal used, however, is imported from Calcutta; this is a bituminous coal of about 11,000 B.t.u., 24 per FIG. 1.-MAP SHOWING LOCATION OF COAL FIELDS AND TRANSPORTATION ROUTES. cent. ash, and costs about $8 per ton. Bituminous coal has not, thus far, been found, but many lignite deposits are known. The most promising lignite deposits are in the Namma field, Fig. 1, situated in the Northern Shan States of Upper Burma, about 30 mi. south of Lashio, the terminus of the Burma Railway, 750 mi. north of Rangoon. The

Jan 7, 1921

SINCE I promised you above when speaking of the melting of metals to teach you to make small crucibles and shells for melting, I do not wish to fail in my promise. For, in truth, since they are instruments that are much used for this procedure, they increase the work if they are not good, and often cause great extra expense as well as necessitating repetition of the work. If they are good they save everything. Therefore, if you have to make them, do it so that they, are greatly aided by art. It is first necessary to have the clay of a good nature, that is, resistant to the force of the fire by its own natural virtue, either when it is lean or when its viscousness is mixed with much talc, and whether it is yellow or white. This should be well freed from small stones and beaten well with an iron, and then thoroughly mixed by hand. With this should be mixed an eighth part of finely ground and sifted iron scale,* and also some [145] young ram's-horn ashes. These things should be well mixed together by hand and by beating them. If this clay should not be strong enough by itself, it is mixed with another lean clay, with crushed peperino, flintstone, or some other stone that in your judgment seems to be arid and resistant. Crucibles are worked on a low potter's wheel turned by hand, or on a high one turned by foot, just as plates are made. Both large and small ones are made. Most of them are given a triangular shape at the mouth, and the shells have a kind of spout for ease in pouring out the metal. This done they are well dried, and baked in furnaces like pots or other vessels. At the end, when they have been thus made they are used for melts.

Jan 1, 1942

EVERY English-speaking mining, engineer or geologist knows that some terms used by his profession are not rigid but vary regionally; for example: what is called a vein by some, is called a lode by others and is known as a reef to their Australian colleagues. There are parallels in, the German language. Since, in addition, the meaning of some words may change considerably in 450 years-and other words may disappear completely-and not only the terminology but the concepts of a science are subject to drastic changes over such a long period of time, translating the Bergbüchlein posed some interesting problems. Old German texts and glossaries such as C. T. Delius' Anleitung zu der Bergbaukunst (1773), Minerophilus' Neues and Curieuses Bergwercks-Lexicon (1730), and H. Veith's Deutsches Bergwörterbuch (1871) proved useful sources of information when defini¬tions of obscure terms were needed. The task of translating was made even more challenging by the author's personality. As Ulrich Rülein von Kalbe was primarily a physician, his information must have been mostly secondhand. Since the nomenclature of the miners of Saxony, where he gathered his material on silver ores, undoubtedly varied from that of the German miners in Hungary, for instance, who probably supplied him with data on gold ores, it is not astonishing that he is not consistent in his use of some expressions. To give an example: there is every indication that Flöz and schwebender Gang (see footnote p. 21) are used interchangeably in spite of his occasional disapproval of such usage. It is obvious that he was an educated man with a questing and active mind and, although he apologizes-not wholly sincerely, one might suspect-for the simple

Jan 1, 1949

By Edward H. Robie

Engineers' Centennial THIS summer, in Chicago, will be celebrated the "Centennial of Engineering" and half a hundred engineering societies will have meetings of one kind or another in the two weeks following Labor Day. It is really the 100th anniversary of the founding of the American Society of Civil Engineers. Centennial of Engineering is merely a convenient label to put on the celebration of 100 years of engineering progress in this country since the ASCE was founded. Engineering, of course, is much older than is thus indicated-thousands of years older. But Americans have a penchant for dramatizing progress by celebrating assumed anniversaries. Four years ago a special 30 stamp was issued on which a Brahma chicken was prominently displayed, with the legend, "1848-1948. Centennial of the American Poultry Industry." We feel reasonably sure that the first dozen eggs was sold considerably earlier than that. Until a hundred or so years ago engineers were generally classified as either military or civil. Apparently a group of civil engineers met for the first time in Augusta, Ga. but no records were kept and the first meeting of which we have definite knowledge was at Barnum's Hotel in Baltimore, Feb. 11, 1839. Forty engineers were present and they decided to form a society. Among the aims of these engineers was "the greatest amount of useful effect at the smallest cost," which is as good a slogan for the engineer of today as it was 113 years ago. It was mentioned that the existence and prosperity of the society depended in no small degree on "the personal conduct and exertions" of the members. "Talents and respectability are preferable to numbers ... from too easy and promiscuous ad mission, unavoidable, and not infrequently incurable, inconveniences perplex most societies."

Jan 1, 1952

By G. P. Walters, W. C. Fuller

THE production of thin films of beryllium became essential early in the irradiation program at Harwell in order to study the fundamentals of irradiation damage in this metal. In common with other metals, electron-microacope specimens of beryllium can be produced by different techniques. The techniques used to produce thin-film specimens varied according to the starting material. Most of the starting material was -0.060 in. thick. Large-area specimens (1 in. long by 0.5 in. wide) were chemically thinned to -0.005 in. thick in a solution containing 85 pct orthophosphoric acid, 10 pct chromium trioxide, and 5 pct sulfuric acid at 70°C prior to electropolishing. Small-area specimens, Fig. 1, had to be mechanically thinned prior to electropolishing because chemical thinning considerably reduces the area as well as the thickness. Mechanical thinning tends to produce a worked layer about 0.002 in. deep and hence this method cannot be used to thin bulk specimens below about 0.005 in. thick. Mechanical thinning is carried out by mounting the specimen on perspex then carefully polishing on wet grinding papers. Polishing is continued until about half the initial thickness is removed; the reverse side is then polished in a similar manner. After the bulk specimens have been mechanically or chemically thinned to -0.005 in. they are elec-tropolished in the solution shown in able I at 50" to 80°C. This solution should be prepared by adding the chromium trioxide to the orthophosphoric acid and then the glycerol last. The glycerol should be added slowly because a vigorous effervescence can occur. Electropolishing is carried out by holding the specimen in stainless-steel tweezers and gently agitating in the solution. Masking or "window" techniques are not required for beryllium, good microscope specimens being obtained from the edges of elec-tropolished foils. A stainless-steel beaker should be used, acting as the cathode and solution container. A closed circuit voltage of 30 v is used for polishing. Too low a voltage produces a matt surface and pitting occurs when it is too high. The solution temperature is important. If it is too low, the solution is viscous and bad polishing results and, if too high, etching of the specimen occurs. After electropolishing, the foils are thoroughly

Jan 1, 1963

C. W. GOODALE, * Butte, Mont.-In regard to the employment manager, the North Butte Mining Co. has undertaken that line of work and the rest of the companies are watching the experiment. If it is proved to be the proper thing, the system will be introduced into other mines. We have to combat the opposition to the use of the "rustling card. It is nothing more nor less than asking the nationality, where the plan formerly worked, and whether he is married or single. ROBERT RHEA GOODRICH, Anaconda, Mont. (written discussion?).¬Since the efficiency of the different phases of personnel work employed by industrial concerns, which are bringing about greater efficiency and lessening the labor turnover, the latter being intimately connected with "contentment of mind," depends on the individual workman, it is highly desirable, as far as industry is concerned, to keep the workman's mind and body in trim in order to lessen accidents and produce a higher grade of work. Prevention being better than cure, health supervision of the workmen during employment should be maintained by the employers in order that mental alertness and physical well-being may be obtained. I have long believed, from observation in many plants, that when any problem is dependent on the individual workman, what he believes and what he does is vitally dependent on his health. I will follow with much interest what is to be clone in the future in relation to the subject of health supervision during employment (as well as medical examinations at the time of employment), and I hope this idea will be generally instituted in personnel work. A workman with good health and a contented mind should be an ideal component of a progressive industrial concern. The contentment of the workman is fostered by a number of admirable phases of welfare work which are being still further developed. The mental and physical well-being of labor should be the issue in Labor vs. Capital in the new period of the industrial promotion of the United States into which we are now entering.

Jan 4, 1919

By E. L. Davis

There have been many attempts to devise formulas for flowing efficiency and flow friction of oil-gas mixtures in oil-well flow tubes. Actually, however, flowing efficiency is rarely any real concern of the oil producer and flow-friction formulas contain so many unknown variables as to be of little, if any value. The production engineer is generally concerned with producing as much oil as possible with a minimum expense per barrel, and with the lowest possible net gas-oil ratio. These ends frequently are opposed to each other and the gas-oil ratio usually is sacrificed. In competitive operations, such as in town-lot fields, high current production is the sole interest. In conservative operation the greatest possible amount of oil obviously should be produced by natural flow unless the net formation gas-oil ratio can be improved by circulating gas. In practice this condition frequently exists. It would be a great advantage if the flowing condition of a well could be analyzed to determine the best possible producing status. Anticipating the death of a well so that gas-lift could be started immediately after the death, or preferably before, would save both production and expense. Frequently it happens that circulating gas fails to help a flowing well, or will not flow it after it has stopped flowing naturally. A knowledge of the laws governing flow would save considerable expense in testing such cases. A predetermination of probable pressures and amounts of circulating gas needed to flow wells and give best possible producing conditions would help in designing compressor installations. The optimum producing status of an oil well generally may be obtained by the conditions that subject the producing formations to the least possible back-pressure. This pressure is made up of the weight of the fluid column, frictional resistance to flow and the reaction from the acceleration of the fluid mass. A mathematical calculation of these components to arrive at a condition giving a minimum summation is impractical. Formulas would be complex and the results untrustworthy because it is impossible to assign proper values to the many variables involved.

Jan 1, 1931

By L. Eaton, A. W. Last, J. L. Stevens

COPPER ore from Kennecott Copper's Ray mine, about 60 miles southeast of Phoenix, Ariz., is concentrated at the company's mill at Hayden, some 18 miles south of the mine. The Hayden mill is currently treating 16,000 tons of ore per day by flotation, using raconite, a crude butyl xanthate, as a collector for the sulfide copper minerals and lime as a pyrite depressant.1 The ore contains significant amounts of nonsulfide copper minerals, but recovery of these values has been low. The Hayden mill is now being modified to provide for treatment of future ores by leach- precipitation-flotation (L-P-F). This modification, costing about $5 million, is expected to reduce the loss of nonsulfide copper values and improve overall copper recovery by an additional 2 lb per ton of ore.

Jan 11, 1957

By M. E. Gershon

Conventional methods of drill hole site selection are reviewed briefly. Two approaches using geostatistics are then discussed, both of which have been shown to yield improved results. Finally, a branch and bound algorithm is described which will select the best locations for drilling from a user specified number of possible drill sites. Two options are discussed. First, the user can specify a maximum drilling investment or a maximum number of drill holes and the program will select the locations yielding the minimum estimation variance. This amounts to getting the most for a given investment. Alternatively, a maximum tolerable estimation variance can be specified and the program will select the number and location of the drill holes to obtain the desired information at a minimum cost. Another benefit of the approach is the quantification of the tradeoffs between investment and information obtained.

Jan 1, 1985

By C. B. Murray

Our experience from time immemorial has been that the furnace sampler and analyst usually find one or two, and sometimes more, points less iron than the Lake Superior shippers, but, fortunately, their contracts are iron bound…

Jan 1, 1915

By R. A. Wyman

KYANITE schists in the Sudbury area have been generally described by Haw,1 who has also given particular information on preliminary treatment of three large samples from Dryden township, Ontario.2 Kyanite, garnet, biotite, quartz, and feldspar comprise the main ingredients of this ore. Kyanite is the valuable mineral. About 5 ½ tons of -35 +200 mesh product, made by dry rod milling, screening, and separation on the Exolon magnetic separator, were available for treatment by flotation. Magnetic separation had effectively reduced garnet and biotite so that flotation feed consisted essentially of kyanite, quartz, and feldspar, the kyanite content averaging 32 pct and representing about 86 pct of the kyanite in the original ore.

Jan 1, 1958

By R. Neilson Clark

THE coal-beds of Canyon City are situated six miles below the town, upon the Arkansas River. At this point the Rocky Mountains have thrown out from their main ridge two spurs. The one to the north, containing Pike's Peak and Cheyenne Mountain, is known as part of the "Rim Range;" the one to the west and south is known as the "Greenhorn Range." Against these syenitic mountains, the later rocks are piled and uplifted ; at right angles to the direction of this main uplift is the axis of a lesser plication. On the north, west, and south, the pitch is steep, gradually flattening as it approaches the centre of the basin and rising again to the east at a pitch of about 5", thus forming a perfect basin, the centre of which is only three miles east of the base of the Greenhorn Range.

By R. C. Amero

FULLERS earth is a general name applied to claylike minerals that have high natural adsorptive powers. They are usually distinguished from ordinary clays by a higher content of combined moisture and a lower apparent density. The definition is based on the ancient use of the material for fulling, or cleansing woolen cloth of oil and grease; a more modern definition should mention the ability to decolorize oil and should differentiate between fullers earth, which is naturally active, and certain bentonites which only develop decolorizing power after being leached with strong mineral acids. The distinction between fullers earth and activable bentonite is not a sharp one, since all types of intermediate clays can be found that are more or less naturally active, yet more or less responsive to acid treatment. The differences seem to depend somewhat on the amount of leaching that has been effected by natural ground waters.

Jan 5, 1951

IN welcoming the attending members of the Ameri-can Zinc Institute's Ninth Annual Meeting to St. Louis on April 18, the president of the Chamber of Commerce stressed the notable progress that had been made during nine years, marked by many price de-pressions and internal dissensions, while controversies between miners and smeltermen threatened to wreck the organization, prices dropped, and consumption grew languid for want of organized publicity and research. The reports and recommendations of Percy B. Butler, chairman of the Adjustment Committee, and F. C. Wallower, chairman of the Galvanizing Committee, might well be adopted as the institute's objectives. In reply to the speeches of welcome to St. Louis, Arthur Thacher reminded the delegates that the cor-ner stone of progress in the mineral industries was laid by the formation of the American Institute of Mining Engineers in Wilkes-Barre, Pa., in 1871, and the dedication of that organization to the exchange of ideas and methods of the winning of metals and non-metals from their crude state. The activities of the American Zinc Institute constitute, he said, a valuable phase of that work. Mr. Thacher forecast the treat-ment of 1 per cent zinc ore. After the reading of the report of the board of directors, in which Scott Turner and Louis Boschern were named as honorary members of the institute, a survey of world zinc conditions by A. J. M. Sharpe of London was presented. He held pres-ent conditions in China responsible for much of the present depression in zinc. World stocks on, April 1, 1927, were estimated as 52,900 metric tons. Adolph Boldt's paper on "Solidarity in Industry" was followed by a survey of the Tri-State district by Otto Ruhl, who emphasized the importance to the dis-trict of the organization of the Tri-State section of the A.I.M.E., which already has 135 members and asso¬ciates. He also mentioned .that flotation in the Tri¬State field is adding 1500 tons of concentrate to the weekly production. "Mining Economics" was the subject of Julian D. Conover, secretary of the Tri-State Zinc and Lead Ore Producers Association. He gave a detailed report on the costs of mining and milling in the district.

Jan 5, 1927

By Hugh M. Roberts, R. D. Longyear

Introduction ............................ 27 GEnERal Geology........................... 29 The ORebodY in Western Falco~ridgI TownsRip........... 31 Quartzite-Graywacke Formation................... 33 Greenstone............................ 33 Norite ............................. 33 Metamorphism.......................... 35 The Orebody........................... 36 Mineralogy ........................... 37 Grade of Ore........................... 42 Genesis oF tEe Ores . :....................... 43 Summary of Various Hypotheses.................. 44 Magmatic Segregation by Crystallization of Sulphides........ 44 Gravitational Segregation of Molten Sulphides at the Base of the Magma 45 Intrusion of Molten Sulphides after the Consolidation of 'he Nurite.. 45 Deposition by Hydrothermal Solutions.............. 46 Magmatic Segregation by Extraction from Crystallizing Norite... SO The Relationship between the Exploration and Theories of Origin .... 50 Volume Relations of Norite and Sulphides............... 62 Intimate Association of Norite and Sulphides............. 53 Granitic Material........................ 54 Uniform Content........................ 54 Sulphides in Walls......................... 54 Absence of Typical Hydrothermal Minerals.............. 55 SUmmaRY................................ 56 Introduction During 1916 and 1917. the E. J. Longyear Co. of Minneapolis. Minn., carried out a campaign of exploration for nickel-copper ore in the Sudbury District of Ontario. The work was initiated by W. E. Smith. a resident of Sudbury. who called the attention of W. J. Mead. Chief Geologist

Jan 1, 1918

By W. D. Robertson, H. H. Uhlig

The intermetallic compounds MgzSn and Mg2Pb are two of the important series of stoichiometric compounds which magnesium forms with elements of the fourth group of the periodic system. Since there is a complete series of compounds, all possessing the same comparatively simple structure, a unique opportunity is presented to study their properties with respect to increasing atomic number of the anion as it varies from silicon and germanium, through tin and lead. The present work deals with the two lower members of this group, and it is hoped eventually that additional data regarding the silicide and germanide will be obtained. The results of such a complete study provide part of the essential basis for the empirical correlation and theoretical treatment which, in other systems, has contributed to an understanding of inter-metallic compounds and the metallic'state in general. Some experimental data are already available in the literature. However, they are fragmentary and limited in significance owing to the methods of preparation employed and the impure materials available at the time. It was our objective, therefore, using pure metals and improved metallurgical methods of preparation, to produce stoichiometric compounds of high purity for the study of their electrical and chemical properties. We felt that a detailed investigation of chemical properties, about which relatively little is known, combined with electrical properties, would be a significant contribution to the understanding of these compounds and in particular to the mechanism of corrosion associated with types of bonding in alloy systems. The chemical studies are reported elsewhere. Previous Investigations Previous work concerning the electrical properties of these compounds was undertaken in connection with the establishment of the two phase diagrams which are available in Hansenl and Beck. The first comprehensive investigation of the electrical conductivity of magnesium-tin and magnesium-lead alloys was made by Kurnakov and Stepanov.3 This was followed by Grube and Voss-kiihler4 who studied electrical conductivity and thermal expansion over a wide range of temperature and who, unlike Stepanov, appreciated the significance of the large solid solubility of tin in magnesium and took some precautions to obtain an equilibrium state. However, at the time these investigations were made, neither pure magnesium nor

Jan 1, 1949

Virginia Polytechnic Institute, Department of Mining Engineering, Blacksburg, Va Otto C Burkhart, Professor of Mining. The titles of pertinent publications have been abstracted from the Bulletins on Research and Publication This material has also appeared, in most cases, under other auspices Presumably, the Bulletins whose titles are quoted may be had for the cost of postage The coals of Virginia (1927), Ceramic resources of Virginia and their development (1929), Effect of ilhum crucibles on volatile determinations of coal (1930), Possibility of briquetting southwest Virginia coals (1930), Coking of semi-anthracite coal of Virginia (in preparation), Distribution of ash in the Merrimac coal seam (1929); Unit coal studies on some Virginia coals (1931), Sulphur forms in Virginia coals (1931); Comparison of results of fusion point of coal ash obtained by two different methods

Jan 1, 1933

By Donald L. Anderson

Presence of hot water brought on by volcanic action nearby has severely complicated mining in the Limon gold mine in Nicaragua. Routine pumping problems have been multiplied and ventilation is a major problem. Enclosing rock is so hot that 20 pct of all power generated at the mine is consumed by forced ventilation. But hot water underground, however disagreeable and troublesome, may be handled and surmounted like any other difficulty if the estimated profit margin permits. Empresa Minera de Nicaragua's Limon mine is a 400-ton gold-silver producer located in western Nicaragua about 60 miles northwest of the capital city, Managua, and some 45 miles from the Nicaragua-Honduras border. Limon is situated in a low- lying district with a nearby chain of active and semi-active Tertiary volcanoes.

Jan 6, 1959

By W. O. Hotchkiss

AN ESSENTIAL mental equipment for planning exploration is the fullest possible. knowledge of the way in which the orebodies occur in the region to be explored, also the realization that in no mining district is this knowledge complete, and that new: facts of importance will he revealed to the explorer in every exploration if he is in the proper frame of mind to grasp them. The geology, of the ore deposits of the Gogebic Range for a long, time was thought to be relatively simple, but work in recent years, by several men, has proved that this is not the case. We now realize that we are far from knowing all the factors that have resulted in the localization of ore deposits. For example, we have long known that the intersections of the dikes and. the foot wall were favorable places to look for ore, but only within the last few years have we learned that there are several horizons' in the various members, well north of the foot wall, that are likely to carry ore. The influence of the numerous cross faults on orebodies is not known or appreciated beyond a general realization that they are important. Just how they may be favorable or unfavorable to the localization of ore is not known. Such elementary information as the positions of these faults is just beginning to appear on the mine maps. Such being the condition, one can hardly overestimate the importance to the various operators and fee owners of careful studies of conditions in their properties for the purpose of assuring themselves that they are not missing valuable ore-that they are doing all the exploration that their situation demands in order to secure maximum returns. Valuable ores have been missed in the past and will be missed in the future. Only with a complete knowledge of all the factors that have united to produce ore could anything else be expected. The purpose of this paper is to call attention to these facts briefly and to suggest a few of the principles that should guide effective exploration. The foremost principle is that the man who starts out with the idea that he knows all about the mine geology of the Gogebic Range is starting with a heavy handicap.

Jan 8, 1920