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By V. J. Bishop, R. G. Beverly

Recent publicity has focused attention on the hazard of lung cancer among uranium miners. Many mining people feel the danger has been exaggerated. Whether or not this is the case, the industry must thoroughly evaluate this potential hazard and take corrective measures to minimize the threat of radiation after-effects and to maintain the level of radiation in mines within the presently-accepted limit. The measurement and control of radon gas and its solid radioactive decay products, Po-218, Pb-214, Bi- 214, and Po-214, should be the one facet of most concern to uranium miners in any radiation control program. To illustrate the radioactivity involved with small quantities of radon gas, the activity from the decay products of five milliliters of radon gas (imagine a 5-ml vial) would be adequate to raise one cubic mile of air to seven times the recommended maximum working level of 300 [ ] (micro micro curies) per liter. This would be enough radioactivity to raise to the maximum working level a 6 x 8-ft drift which extended around the world 160 times. Obviously, a little radon gas goes a long way.

Jan 8, 1961

In an earlier day, a moderate-sized 600 tpd mine could easily require 60 working faces and might use five supervisors. The miner had a tonnage rate as an incentive and was largely his own boss. With the advent of conventional mining machine crews, the typical pattern of resource used changed radically. The number of work places could be cut by a factor of ten, but supervision only by a factor of somewhere around three, or at most, five. Obviously, supervision was increased. Capital use rose at the same time by a factor of approximately eight. Materials used, such as powder and bits, probably in- creased in both quality and unit cost, too. It certainly required a better-trained man to run the machines, but fewer miners were needed. It is clear that each input factor such as land, labor, capital and management, has changed significantly and it would be foolish to attribute all the gain to improved machines. However, concentration of work was a vital consideration in the change, sketched above, and such focusing of work in fewer areas could not have occurred without high capacity mining machines.

Jan 11, 1968

By Geo. W. Goetz

The following tables show the analyses of ores from nearly all of the mines which will produce over 10,000 tons of ore each during the season of 1890. There are many small mines now in the course of development, some of which may become large producers. Many of the mines produce several different grades of ore, but the analyses given in the tables are fair averages of ore such as the respective mines can deliver. Most of these analyses were obtained from the agents of the respective ores, and are averages of the season of 1889. One can state positively that over 75 per cent. of all the iron-ores of the Lake Superior district will average over 60 per cent. of metallic iron. During the past 34 years this region has produced about 48,137,421 tons of ore, the different districts contributing about as follows: Marquette District,. 29,754,057 Menominee " .10,415,859 Gogebic " . 6,622,194 Vermilion " . 2,342,991 Miscellaneous,. .. .. 2,320 In the year 1889, the product of all the districts was nearly '1,300,000 tons. The product of the entire region for the season of 1890 may exceed 9,000,000 tons. This large amount of ore is shipped to the lower lake ports, from Escanaba, Marquette, Two Harbors and Gladstone.

Jan 1, 1891

By W. Spencer Hutchinson

THE relative importance of mineral production in British South Africa is about as follows: Gold, $200,000,000; diamonds, $40,000,000; coal, $18,-000,000; asbestos; $3,000,000; chrome ore, $2,000,000. In 1926 the gold mines paid $42,000,000 in dividends, the diamond mines $13,000,000, coal nearly $3,000,000, others less than $500,000. The recorded history of South Africa starts with the visits of the Dutch and the English in the sixteenth century, followed by the settlement of Cape Colony by the Dutch East India Company in 1651: The English acquired Capetown in 1806 and conflicts between English and Boers were a part of the history, from that, time on. Transvaal was settled in 1835, following the Great Boer Trek. The mining of diamonds became im-portant in 1870; the production of gold from the Rand in 1890;' the export of chrome ore in 1910; and the dis-covery of platinum in 1925. South Africa has a race problem, resulting not alone from the disparity of numbers between whites and natives, more than seven blacks to each white, twenty to one in Southern Rhodesia, and three. hundred to one in Northern Rhodesia; but because of the division of the white race between English and Cape Dutch or Afrikaans. The natives are also of many tribes.

Jan 6, 1927

By Henry S. Brown, Jean E. Tilden

Pyrite, pyrrhotite, chalcopyrite, and sphalerite from deposits distributed within the Piedmont and Blue Ridge provinces of North Carolina and adjacent areas were examined by atomic absorption spectrophotometry for cobalt, nickel, manganese, lead, tin, chromium, molybdenum, and gold. The ore samples were also examined petrographically. Cobalt and nickel, in general, enter pyrite and pyrrhotite rather than chalcopyrite and sphalerite. Manganese generally enters sphalerite rather than the other phases where an alternative is possible. The presence of tin in sulfide minerals was noted in a group of deposits east of the known occurrences of tin oxide (cassiterite) in the Kings Mountain belt, which may indicate the presence of a more extensive tin belt in the southeastern Piedmont than was previously recognized. Pyrrhotite from a group of four deposits in Jackson and Clay Counties, North Carolina, differs from pyrrhotite from other Ducktown-type deposits in having cobalt/ nickel ratios less than one, finer grain sizes, and colloform texture. These differences suggest that that this group of deposits has had a history different from that of the other Ducktown-type deposits studied. No significant conclusions could be made based on the distribution of lead, chromium, molybdenum, or gold.

Jan 1, 1975

By M. G. Gulley

The drilling for and production of crude oil in the Lima-Indiana and Michigan fields were directly and profoundly affected by the severe strain to which the petroleum industry was subjected during the year 1931. Serious and long-continued overproduction in the large flush areas of the western and southwestern fields, coupled with a nationwide decrease in the annual rate of consumption-increase, served to precipitate ‡ This curve is the Mid-Continent price for 38" gravity crude and hence. affords a basis for estlmating the influence of general factors upon the price structure m these fields. a mid-year economic depression which was functionally reflected in every producing area in the United States. A study of the curves of price changes in portions of the central west territory (Fig. 1) will demonstrate this relationship as well as the ensuing upward trend, which developed when pressure was artificially relieved, at least for the time being, in the producing areas in the southwestern states. All field activities in the Lima-Indiana and Michigan territory during 1931 follow the price curve closely: the mid-year depression was evident in drilling activities— both wildcat and within the proved limits of producing fields, in pipe line

Jan 1, 1932

By William Daly

THE application of artificial refrigeration, or air-conditioning, to the ventilation of deep, hot mines has long been a subject of interest to the operators of such properties. Artificial cooling of the air in theaters, railroad coaches, and various industrial plants has been so successful within recent years that it has been natural to assume that the adoption of similar methods would afford a ready solution to the difficult problem of mine ventilation. It should however, be obvious, that although there may be nothing technically impossible in the application of this process to mine ventilation there is a great economic distinction between the maintenance of a high standard of comfort for a large number of people in a relatively small space such as a theater and the cooling of air to improve working conditions for miners scattered throughout the extensive workings of a large mine. Many methods of air-conditioning have been considered by the management of the Anaconda Copper Mining Co. at various times, but until the development of the process to be described in this paper none has seemed economically practicable.

Jan 1, 1934

By V. E. McKelvey

Some understanding of the United States mineral resource potential is essential for planning and policy making for the future. Reserves of some minerals are essentially lacking and for many others they are sufficient for only short term needs. Estimates of undiscovered resources of many minerals are substantial but are insufficient to support long term requirements, particularly if they continue to increase as they have in the past. Presently, subeconomic resources of some minerals such as aluminum are huge, but their recovery may require increased amounts of energy, which poses problems both as to cost and availability. Beyond these identifiable components of the United States mineral potential, what are the prospects? If they could be identified specifically, of course, they would be included in the above. An unappraised potential of new production and discovery can be expected to exist in known districts, where unproved methods of exploration may yield new discoveries; in new types of ore deposits; in metallogenic provinces as yet unrecognized or poorly explored; in frontier areas and in deeper parts of the crust as yet unexplored; and in presently subeconomic sources that may come within economic reach as the result of technologic advance. Other sources may extend the life of domestic material supplies -- substitution of abundant for scarce materials, recycling and prevention of waste, improved efficiency in recovery and use, and conservation of use.

Jan 1, 1976

By K. Thirumalai, D. P. Schlick

Longwall Technology has a potential of resulting in safety and productivity improvements of U.S. underground coal mining similar to those experienced by the introduction of continuous miner systems. The study presents a comprehensive national evaluation of longwall technology to assess the potential of longwalls to improve health and safety and coal productivity. The study was conducted by the authors during the spring of 1980 as part of MSHA New Technology Coordination activities and with a view to examine the factors that may limit the acceptance of longwall technology in the U.S. coal mining operations. The study points out areas where adjustments need to be made in MSHA regulations and enforcement to help Longwalls. A two-entry longwall system appears to offer a practical method of improving underground coal productivity and safety. Applying regulations that are primarily designed for room and pillar methods to longwall mining, in some instances, reduces the effectiveness and productivity benefits feasible by new technology application. Controlling dust is the single predominant problem in the design and operation of longwalls in the United States. The results of this study points out a need for a coordinated program between government and industries on dust control technologies for examining acceptable technological options to control dust in longwalls without restraining the production capability of the system.

Jan 1, 1981

By Edward L. Clark, Garrett A. Muilenburg

THE first record of the discovery of iron ore in Missouri was Marquette's observation in 1673 of brown iron ore, or limonite, in the Mississippi River bluffs just north of the mouth of Apple Creek in southeastern Perry County. There is no record of any attempt to mine or smelt Missouri iron ores until 1815, when the Ashebran furnace was erected at the Stouts Creek shut-in near Arcadia, Iron County. Some limonite was treated in this furnace, the first iron furnace west of Ohio, but most of the ore was hematite from Shepherd Mountain and adjacent deposits. Eight years later, in 1823, the Perry furnace five miles north of Caledonia, Washington County, was constructed to smelt limonite ore. It was not until 1890 to 1900, however, that these ores attracted considerable attention. Nearly 300,000 tons had been produced by 1911, and this production had come from 24 counties in the Ozark region. For the next two decades, until 1931, essentially all activities ceased. During the depression years of the thirties when employment was low many people turned to the brown ores for subsistence; consequently production was increased. World War II produced another stimulus to the industry. The availability of risk capital in the past three years has revived interest in these deposits, although no appreciable increase in production has resulted.

Jan 1, 1954

By Linn M. Farish

The reported production of petroleum in the Dominion of Canada for 1930 was 1,555,199 bbl., an increase of 455,373 bbl. over 1929. Alberta accounted for nearly all the production with Ontario and New Brunswick, the other two productive provinces, contributing less than 1 per cent, of the total. The completion of about 25 producing wells in Alberta was more than sufficient to offset the decline of the older wells in that province and the small decline in Ontario. The production of about 5000 bbl. in New Brunswick represents a restricted output to meet the market demand. Table 1 shows the production by provinces for the past 10 years. The consumption of natural gas for all purposes in Canada reached a new record of practically 40,000,000,000 cu. ft. in 1930, which was a considerable increase over 1929. The estimated value of the gas output was $10,500,000, against a little over $5,000,000 for the total petroleum production. Gas wells in Alberta accounted for over 75 per cent. of the total, with Ontario second and New Brunswick a poor third. The outlook for 1931 is for very little change in production of either gas or oil in Ontario and New Brunswick but for a substantial increase in both in Alberta.

Jan 1, 1931

By K. R. Weller

The Ardlethan Tin Ltd. concentrator typically recovers 55% of the tin in a gravity concentrate at 51% grade from fresh ore assaying 0.5% Sn. Coarse gravity concentration is performed in a complex circuit involving Reichert cones, spirals, shaking tables and two regrind mills. The paper describes how flow and size-by-size sample data from a steady-state survey were used to construct a computer model of the plant involving 46 process streams. The data reduction involved a computer- aided mass balancing technique, recovery-size modelling of gravity concentrators and the use of a mineral dressing flowsheet simulator. The model was used to simulate possible rearrangements of the available equipment. Early simulations indicated that improved performance could be obtained by using spirals to-treat cone middlings or tailings rather than cone concentrates. A test spiral rig was used at Ardlethan to determine typical performances for all cone product streams and the results were incorporated in new simulations. A revised circuit was recommended and implemented by Ardlethan Tin as far as physical restraints within the plant would allow. Production figures show that a substantial increase in tin recovery and 10-15% increase in milling rate were achieved following the circuit changes, and these improvements were sustained over a six month period.

Jan 1, 1984

By M. S. King, B. N. P. Paulsson

Four vertical boreholes in the vicinity of an electrical heater simulating a canister of nuclear waste in a granitic rock mass have been logged with an acoustic borehole sonde before and after thirteen months' heating. Excellent control of the structural geology and fractures present in the rock mass was provided by the considerable amount of oriented core recovered from the four boreholes used for acoustic logging and the large number of others used for a variety of rock mechanics instrumentation. Compressional and shear-wave velocities were measured as a function of stress on some twenty core samples, water-saturated and dry, which were recovered from the four acoustic logging boreholes. Further control was provided by a cross- hole acoustic monitoring program conducted before, during and after heating between the same four boreholes, and by measurements of acoustic velocities in an isolated block of granite in the same heater drift, which was subjected to an increase in temperature and to changes in uniaxial stress. It is concluded from the acoustic logging tests, taken in conjunction with the acoustic cross-hole and heated block experiments, that acoustic techniques: 1. Provide a means for locating and delineating systems of weakly- bonded or open fractures within the rock mass; 2. Provide a sensitive means for monitoring a rock mass for changes in moisture content or structural damage to the rock fabric induced by thermal or mechanical loading; 3. Together with the rock bulk density yield the elastic constants of the rock mass.

Jan 1, 1982

By R. C. Canby

The American water-jacket furnace is the outgrowth of lead-smelting at Eureka, Nev., subsequently developed in Utah and Colorado. Early smelting in Virginia, New England, or the Missouri-Kansas-Illinois district seems to have had no direct influence in the development of this furnace. First Decade, 1870 to 1880. In 1870, the draft-furnace was used in Nevada, coincidentally with the first crude sandstone blast furnaces, which were 2 or 3 ft. sq., with Sturtevant fans or small Roots blowers, and sheet-iron or water-cooled tuyeres. Stetefeldt, Liebenau, Albert Arents, and 0. H. Hahn mere the early metallurgical leaders. Arents's siphon-tap and the re-establishment of the furnace-bosh mere the most important improvements of the decade. Second Decade, 1880 to 1890. At first there were ,many small local plants; but by the time Eureka had reached its maximum production of lead-ore, two custom works (the Eureka and the Richmond) were treating all the ore, the miners having learned the economy of smelting at larger and well-constructed plants. In the early eighties, most of the features of modern practice were already discernible at Salt Lake, Leadville, Denver, and Pueblo. The small square sandstone furnaces had been replaced by rectangular water-jacket furnaces, mostly 36 in. wide, and from 60 to 80 in. long at the tuyeres, which entered between cast-iron water-jackets. Subsequently, Franz Casin, at the Holden works, Denver, put the tuyeres in the middle of the jackets, and many other improvements were made by him and others, so that the cast-iron jacket became the favorite, until the possibility of

Jan 1, 1913

By C. H. Mathewson

IN a series of papers published recently,1 R. F. Mehl and associates have studied the characteristics of form and orientation of many segregate structures and have found diversified conditions which can be explained only by postulating some specific kind of cooperative mechanism permitting the matrix lattice in some favorable region to transform into the segregate lattice in an adaptable region presenting a geometrically similar arrangement of atoms. We have collected the published data on crystallographic relationships of this sort, chiefly derived from Mehl's work, in Table 1. It is evident at once that the crystal structure of the matrix does not uniquely determine the location of the plate structures or other forms assumed by the segregate. Thus, the first seven items in the table represent precipitation of platelike forms from a matrix of face-centered cubic structure, but these plates are found stratified along planes of form {111 }, {100 }, {110 } or another unidentified form, depending upon specific conditions involving the nature and concentration of the segregating substance. Again, in a matrix of body-centered cubic structure, plates, needles or stars have been found and the favored inner surface of segregation may be a plane of form 11101, 11121, 12101, or indeed a surface without crystallographic indices defining a bundle of close-packed lattice lines (strings of atoms) taken more or less at random. Such a surface might be formed ideally by revolving one of these parallel strings of atoms around another as an axis. Hanemann and Schroder2 recently discussed these questions, principally with relation to original conceptions concerning the process of

Jan 1, 1932

By H. E. Stauss, G. Sandoz

THE purpose of this note is to draw attention to the possibility that a melt may be contaminated by a material not in direct contact with it by means of gaseous intermediate agents. In recent years silicon has assumed a position of importance because of its use in rectifiers and transistors and close attention has been required to control of both purification and contamination during all stages of preparation.' This note reports the observation that a graphite heater may have contaminated silicon ingots without direct physical contact through reactions that developed gaseous products. Several ingots made with the equipment of Hino and Stauss,2 using a graphite heater in a dried helium atmosphere, were found to have a small amount of a very hard substance on the free surface. X-ray analysis by F. W. von Batchelder showed the sub- stance to be Sic. Similar contamination was not found when the heater was tantalum, indicating that the carbon had not come from an original impurity in the silicon powder. One source of the carbon could have been volatile matter released from the graphite heater. This heater had been used about ten times at the time of the observations. A second source of carbon could have been a direct reaction between the quartz crucible and the graphite heater to form CO, or an indirect reaction involving a crucible-melt interaction and volatile SiO as an intermediate product. Such reactions should have developed Sic on the heater; and in fact a yellow powder did form on the inside of the graphite heater although its composition could not be determined. References 'H. C. Torrey and C. A. Whitmer: Crystal Rectifiers (1948) Chapter 10. New York. McGraw-Hill Book Co. 2 J. Hino and H. E. Stauss: Trans. AIME (1952) 194, p. 656; Journal of Metals (June 1952).

Jan 1, 1954

By Colin C. Rae

The absence of paraffin and other oil hydrocarbons in the soil although they are concentrated in extensive deposits in some localities, the common distribution of plant remains through many formations that are not productive for oil, and many other factors, seem to indicate the existence of an intermediate organic compound between the complex plant compounds and the petroleum hydrocarbons; and much evidence points to the humus acids or associated organic compounds, which are probably collected by surface waters and concentrated in certain areas by means of precipitation by electrolytes, which would be contained in sea water or possibly in various inland seas or lakes. Present-day Evidence There are many present-day evidences of the association of petroleum with humus acids. Binney, in 1912, made observations without explanations on the peat mosses of Down Holland, England, where he found petroleum being formed by decomposition in the presence of an infiltration of sea water. The analysis of a typical peat will show its relationship to the humus acids under consideration. Sample No. 1, SamplE No. 2. PXr Cent. PER CENt. Water......................... 20.0 29.6 Ash.......................... 3.0 3.05 Fiber.......................... 47.0 54.95 Humus acids................ 30.0 12.50 J. D. Haseman and others have noted the association of asphalt and hydrocarbons with the swampy, boggy areas, particularly adjacent to the sea. Many of the rivers carry much humus acid in solution, and some tropical rivers carry in the aggregate millions of tons of humus each year. The amount of humus is a variable factor, depending on climatic conditions, and on the salts and alkalies present in the water, also on the density and temperature.

Jan 1, 1923

By Colin C. Rae

The absence of paraffin and other oil hydrocarbons in the soil although they are concentrated in extensive deposits in some localities, the common distribution of plant remains through many formations that are not productive for oil, and many other factors, seem to indicate the existence of an intermediate organic compound between the complex plant compounds and the petroleum hydrocarbons; and much evidence points to the humus acids or associated organic compounds, which are probably collected by surface waters and concentrated in certain areas by means of precipitation by electrolytes, which would be contained in sea water or possibly in various inland seas or lakes. Present-day Evidence There are many present-day evidences of the association of petroleum with humus acids. Binney, in 1912, made observations without explanations on the peat mosses of Down Holland, England, where he found petroleum being formed by decomposition in the presence of an infiltration of sea water. The analysis of a typical peat will show its relationship to the humus acids under consideration. Sample No. 1, SamplE No. 2. PXr Cent. PER CENt. Water......................... 20.0 29.6 Ash.......................... 3.0 3.05 Fiber.......................... 47.0 54.95 Humus acids................ 30.0 12.50 J. D. Haseman and others have noted the association of asphalt and hydrocarbons with the swampy, boggy areas, particularly adjacent to the sea. Many of the rivers carry much humus acid in solution, and some tropical rivers carry in the aggregate millions of tons of humus each year. The amount of humus is a variable factor, depending on climatic conditions, and on the salts and alkalies present in the water, also on the density and temperature.

Jan 1, 1923

On Dec. 8, 1916, at a meeting held at the Massachusetts Institute of Technology, the John Fritz Medal was presented to Professor Elihu, Thomson, "for his achievements in electrical invention, in electrical engineering, in industrial development and,in scientific research." Professor Albert Sauveur presided. John J. Carty, chairman of the Presentation Committee of the Board of Award, made a short address-on the history and significance of the medal. He was followed by E. W. Rice, Jr., president of the General Electric Co., who spoke at length of the achievements of Dr. Thomson, whom he called "one of the world's most prolific and industrious inventors and scientists." Among other things, he said: "In the, field of electrical inventions alone, Professor Thomson has been awarded something over 550 United States patents, and in other fields; notably mechanical work, about 150 patent.,. he has made contributions to the world's scientific, and technical literature, in several hundred articles describing not only his own dis-coveries and inventions but making remarkably interesting contributions to scientific speculation and thought. "A skilled workman, he is always able himself to do the work which he asks others to perform. "His inventions are the result of such profound and accurate knowledge,. and developed with such skill, that they almost invariably work on the first, trial in accordance with expectation." Dr. Richard C. Maclaurin, President of the Massachusetts Institute of Technology, spoke of the personality of the man as well as of his accomplishments, as follows: "He has not only clone great things himself, but has shown ,in intense desire to help all who are struggling earnestly with scientific problems. He has proved an inspiration to an ever-widening circle of engineers and others who have entrusted him with their secrets and sought his help in overcoming their difficulties. They have done this knowing. that they had only to ask in order to get the full benefit of his

Jan 2, 1917

K. Baumgarten has returned from active service in France. He reports that he saw C. W. Campbell, formerly with the 2d Engineers on the Chateau Thierry front, and believes that the latter returned to the United States on August 1. He also saw J. J. Croston; G. J. Sielaff, recently transferred to the Gas Service; Thomas M. Smither, survivor of the Tuscania after a 10-mile swim to Ireland. While in Paris he en-deavored to see Prof. Sauveur, but was unsuccessful. F. K. Borrow was given a commission as Lieutenant in the Royal Garrison Artillery in 1914, but had to relinquish it, on account of ill health, in August, 1915. His health has much improved and he hopes to resume active work toward the end of this year. Davis, A. W:, see British Columbia Engineers, below. Alfred Fox, Jr., enlisted in the Public Schools Brigade, Royal Fusiliers, in September, 1914; was gazetted Lieutenant in the Royal Field Artillery in December, 1914, promoted to Captain in November, 1915, and Adjutant to 78th Brigade, Royal Field Artillery, in January, 1916. He was appointed Staff Captain of the 12th Divisional Artillery in November, 1917. He has served continuously in France since July 1, 1915. He was awarded the Military Cross in January, 1917, and four times mentioned in despatches. E. Fraser-Campbell writes that he joined the London University 0. T. C. in January, 1918, for five weeks; enlisted with the Argyll and Sutherland Highlanders in February, 1918, and attended a training course for officer cadets at Chatham for six weeks. He was commissioned 2d Lieutenant, Royal Engineers, in April, 1918. After two months on home training at Chatham, he landed in France on June 23, 1918, posted to 180th Tunnelling Co., R. E., and is now with his unit up on the line.

Jan 10, 1918