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Freeman, the English historian, said that he had learned from Macaulay "never to be afraid of using the same word or name over and over again if by that means anything could be added to clearness or force. Macaulay never goes. on, like some writers, talking about ' the former ' and 'the latter ', 'he ', 'she ', 'it), and 'they’, through clause after clause, while his reader has to look back to see which of several persons it is that is so darkly referred to". He might have learned also from Macaulay that a preposition makes a feeble ending for a serious statement. How often do you hear 'the former' and 'the latter' in conversation? Good conversation is a guide not to be disdained. When you must use 'the latter ', do not confuse it with 'the last '. Cheap labor, cheap fuel, and cheap transport are essential, the latter [last] being particularly important in base-metal mining. The apparatus may be used to determine such gases as hydrogen sulphide, chlorine, oxides of nitrogen and some others, as well as sulphur dioxide. In the case of the latter two, etc. The two last mentioned are "sulphur dioxide" and "some others". He should have stated which two, and he should have avoided that wretched phrase "in the case of ". Pinning may be partly prevented by use of chalk, oil, or turpentine. The latter [last] is beat. "Partly prevented" is a poor phrase. 'Prevented' is a word that does not lend itself readily to modification. He means ' checked ' or 'corrected '. These steps are necessary to produce the gas, crude oil, and ammonia, the latter [last] of which is in solution in the water obtained along with the oil.

Jan 1, 1931

By RICHARD L. HUMPHREY

IT IS proper that there should be a brief accounting of the stewardship which was entrusted to the Joint Conference Committee by resolution adopted by the. Organizing Conference on June 4, 1920, in part as follows: RESOLVED, that it is the sense of this Organizing Conference that the Joint Conference Committee should be entrusted with making provision for putting the conclusions of this Conference of engineers into effect, etc. Pursuant to this authority, the Joint Conference, Committee has acted as an Ad-interim Committee has- prepared, a synopsis of the proceedings of the Organizing .Conference, has edited and published the Constitution and By-Laws adopted by this Conference, and. has issued an invitation to become Charter Members of The Federated, American Engineering Societies; to the list of organizations to whom invitations had been extended to attend 'the Organizing., Conference. The Committee in connection with this invitation offered to the extent of its ability, such assistance as might be-desired; and arranged in many cases for one or more of its members to be present when the matter of membership in The Federated American Engineering Societies was considered. . .

Jan 1, 1920

The Ural Mountains, which were formerly the dividing line between Asia and Siberia, area chain of low mountains, the highest peaks reaching only a little over 5000 ft. The country has been much eroded and the mountains now appear as rounded hills. In the central and northern parts turf swamps abound. The range is covered with forests except at the extreme southern end. The trees are mostly pine. Birch grows on cut-over areas, but never to large size. The rivers are small or the fall is slight, so no large water powers are available. A series of rivers with a north and south course, and which are navigable for long distances, furnish cheap transportation during the summer months. Railroad communications are very insufficient. The first active exploitation of the mineral wealth was initiated by Peter the Great, who sought iron and copper for use in his wars against the Swedes. He selected a blacksmith named Demidoff to supervise operations and gave him rights to most of the Ural and to the Altai. The Nijni Tagil Estates are still in the possession of the Demidoff family. The original large grant was subsequently subdivided through inheritance and marriage, but the Ural is still a country of very large estates, some of them held as leases only and some of them by actual ownership.

Jan 6, 1919

By Robert F. Mehl

Jan 1, 1944

By Robert F. Mehl

Jan 1, 1944

By Donald H. McLaughlin

THE activity and enthusiasm of pioneers still prevail among workers in applied geophysics1.- Within the year, new devices have .been tried out, instruments and technique have been improved and the methods of application to commercial problems have been increased in many ingenious ways. There is still great need for more skillful interpretation of results in terms of geology, but oil the whole geophysical prospecting is making encouraging progress toward finding its proper place and function in engineering and geological practice. Spectacular successes continue to be reported, particularly .from the Gulf Coast, where the race for salt domes has not slackened, and encouraging results have been giined elsewhere in the mapping of structures in the search for oil. In the mining field, however, it can hardly be claimed that the same measure of success has been obtained, for brilliant efforts worthy of wide recognition have been overshadowed to some eatent by the unfortunate outcome of surveys undertaken unwisely without recognition of the limitations of the work. Consequently, hopes were aroused that could not be fulfilled, and it must be admitted in an impartial survey that there are a few regions, chiefly in the far north, where the standing of geophysical prospecting is somewhat doubtful and where the course of public opinion regarding it shows a certain similarity to the history of the market during the past few months. Reliable work, however, is steadily going 011 and it can confidently be expected that the methods will eventually be regarded in many regions as an essential part of the technique of securing geologic data needed for intelligent exploration.

Jan 1, 1930

By William Paxton Hewitt

Mineral deposits of western Utah and eastern and central Nevada have produced in excess of $8,500,000,000 since 1871. Through 1965, Bingham Canyon had produced over $4,600,000,000 and seven other camps over $100,000,000 each, principally from base metals. In addition, they yield iron and uranium ores; contain the world's largest beryllium reserves; and have produced the United States' most important gold discovery in 25 years. The area is famous for its silver production and its bonanza-type precious metal deposits, but such production has become unimportant. The area's greatest producers of metallic wealth are base-metal deposits in limestones and porphyry-type copper ores. In contrast to silver's decline, gold production has been rising-the result of by-product operations at Bingham Canyon. The area also contains gold deposits in which the gold is so finely disseminated it is not recoverable by panning. The area's gold ores frequently are associated with realgar, cinnabar, and carbon. The ore deposits generally are attributed to Tertiary intrusives,* but, at Mountain City, they may be related to Paleozoic volcanism. Mountain City has yielded rich chalcocite from quartz-pyrite-chalcopyrite bodies in siliceous sediments. Regional stratigraphy and structure are difficult to interpret, 69 per cent of the area being obscured by alluvium or volcanics. In general, central Nevada consists of chert, shale, silty sandstones, lavas, and pyroclastics; eastern Nevada and western Utah of many alternations of limestone, shale, and sandstone. Central Nevada has been structurally active since late Devonian. Although granitic stocks may have intruded eastern Nevada and western Utah prior to the Cretaceous, these areas remained quite stable until affected by the Laramide Revolution. Precambrian exposures, occupying 3 per cent of the area, have not been important hosts. However, the question is raised as to whether Precambrian carbonates, properly situated with respect to invading mineralizers, might yet prove to be important. This paper describes 16 precious metal camps, 6 limestone replacement districts, 2 silver-base metal vein deposits, and 9 miscellaneous types and discusses briefly the 11 * Some ores, as at Ely, are associated with intrusives of. Cretaceous age. major camps that are described in detail in this Volume.

Jan 1, 1968

The meeting of the Institute at St. Louis brought together many members of the Women's Auxiliary, and Mrs. Philip N. Moore, who was nominated as the Director for the St. Louis Section, took the occasion formally to inaugurate the organization in that district. A meeting was held at the Planters Hotel, anti after discussion as to, the aims and objects of the. Auxiliary, officers were nominated for the' Section; the meeting then adjourned for two days, to he resumed in Joplin.. Here a very successful meeting was held, at which the Vice-Chairman, Secretary, and Treasurer were elected. A great deal of interest was arouse under the able directorship of Mrs. Moore the St. Louis Section is likely to become a large and active organization. The president of the Women's Auxiliary, in opening the meetings, told the ladies present of the inauguration of-the-Society in February, 1917, and of the work which had been accomplished up to date. She told how the Society devotes itself to patriotic and humanitarian work along lines acceptable and interesting to the Mining Engineer, standing always alongside and behind the men of the profession. The Central Welfare Committee of the organization has three Sub-Committees: Foreign Relief, Emergency, and Americanization, and under one or other of those heads most of the work of the' Society has been done. Mr. Hoover was responsible for the inception of the Foreign Relief Committee, as its first work was the collection of funds for the supplementary meals for the Belgian Children. Under the energetic administration of Mrs. H. Knox, this sub-committee raised $12,100 in the period between the February meeting and the Declaration of war by the United States, when our government took over the entire duty of feeding starving Belgium. The organization of the Belgian Relief Committee, as it was styled, still remains, but the members are now asked to take up the question of relief in France. The President, Mrs. S. J. Jennings suggested at the St. Louis meetings that one way of working for the foreign relief alight be that all the members of the Auxiliary should, during the period of the war, forego all giving' and receiving of Christmas presents, except those they have been accustomed to give to the poor or in charity, and those they would give to the men in the services of the United States; that the money usually spent on the Christmas gifts should be put into a fund to be sent abroad for the fatherless children of France, as a gift from the families of the Institute. A good deal of discussion followed this proposal, as some of the ladies felt that children should have their Christmas gifts as usual. The Director of the Section emphasized the truth that the Christmas spirit was the .spirit of giving and sacrifice, and that no sacri-

Jan 1, 1918

By W. C. Winegard, A. Galibois, C. J. Beingessner

The effects of solutes on the distribution of two-dimensional configurations of grains in zone-refined tin have been studied. When solutes with partition coefficients (ko) greater than unity are added, three-sided pains become more prevalent and the growth law changes. It is shown by electron-Probe micro-analysis that a solute buildup occurs ahead of a moving grain boundary when ko > 1. It has been found recently1, 2 that solutes with partition coefficients greater than unity have a larger retarding effect on grain growth than solutes with k, less than unity. ko is defined as the ratio of the concentration of solute in the solid to the concentration of solute in the liquid with which the solid is in equilibrium. Niessen and winegard2 have suggested that this effect is probably due to the complex shape changes which occur during the process of grain growth and that no theory based on single boundary motion3-5 can explain the results. They suggested that the dissociation of the unstable fourfold junction was delayed in alloys where ko was greater than 1 because the boundaries at the junction had to move into a region of high solute concentration. If indeed this mechanism were correct, it was felt that not only would the dissociation of fourfold junctions be affected by the solute buildup ahead of the boundaries, but the collapse of three-sided grains would be impaired. These combined effects would naturally lead to a modification in the distribution of the number of sides per grain seen on a two-dimensional section. The present investigation was undertaken to test these hypotheses by examining the grain-growth process in detail. EXPERIMENTS The Distribution of Grain Configurations in Zone-Refined Tin as Seen on a Two-Dimensional Section. Following the method of Bolling and Winegard,6 zone-refined tin was cast into button-shaped specimens and, subsequently, plastically deformed under a drop hammer at room temperature. The resulting flat coin-shaped samples were annealed at 200°C, some for 50 sec and others for 100 sec. The specimens were then examined to determine the distribution of the number of sides per grain, i.e., the num- ber of crystals adjacent to any particular grain in the section. For simplicity, the grains were classified as three-sided, four-sided, and so forth; this concept is schematically illustrated in Fig. 1. As indicated by smith,' it was necessary to examine every grain within an enclosed area to obtain a proper distribution of the relative frequency of each type. The distributions for the two annealing times are illustrated in Fig. 2. The total number of grains examined is also indicated on the figure. It is evi-

Jan 1, 1965

By Finlay, J. S.

THE North Lily Mine started its career in an unusual way it was discovered by a geologist. The remarkable circumstance of driving a 2400-ft. drift into an unexplored country and "hitting her on the nose," indicates that geologists are sometimes numbered among those whom the Lord loves. Diamond- drilling from surface had previously shown the presence and position of the Ophir beds, and surface showings of pebble-dykes, faults, and bleached rhyolite indicated conditions similar to those at the Tintic Standard "Pot-hole." The discovery drift from the Tintic Stand- ard 700-level reached the North Lily orebody in January, 1926, and development and stoping were continued by Tintic Standard men and equipment until the North Lily shaft was sunk and put into service in May, 1928. The discovery drift was run on a cooperative basis by the Tintic Standard and North Lily mining com- panies. Finding the North Lily mine cost the North Lily company $26,000. The Tintic Standard Mining Co. furnished men and equipment to drive this discovery drift at a fraction of what it would have cost to find the orebody from surface. This was the beginning of the friendly cooperation that still exists. Through Tintic Standard ground the Tintic Standard paid two- thirds of the cost and the North Lily one-third; the cost of the drift through Eureka Lily, into North Lily ground, was paid by North Lily. Later, another drift from the Tintic Standard 900-level was run on the same plan, excepting that Eureka Lily paid its share of the cost; that is, the Eureka Lily paid one-third of the expense in Tintic Standard ground, and the Eureka Lily two-thirds and North Lily one-third in Eureka Lily ground. This 900-drift was driven by North Lily from the Eureka Lily line to near the North Lily west side-line. From this point the Chief Consolidated continued the drift well into Tintic Bullion ground.

Jan 1, 1929

By C. J. Huffman

MAGNESIUM alloy tubing and hollow shapes are finding increasingly wider usage in practical applications today. Square and rectangular tubing and hollow shapes find [ ] greater diversification in use than standard round tubing. Typical applications are roller conveyors, ladder rungs, spools, furniture, tank car loading tubes, athletic equipment, and business machine parts. In general, the amount of tubing and hollow shapes produced represent a minor portion of the magnesium extrusion business. The magnesium alloys in which tubing and hollow shapes are being produced together with typical properties are presented in Table I. MI A alloy is a low cost alloy possessing good welding and stress corrosion characteristics together with moderate formability and corrosion resistance. It is widely used for low strength applications. AZ31 B, alloy is used for moderately stressed applications and possesses good corrosion resistance and formability with fair welding characteristics. AZ61 A alloy has slightly higher physical properties than AZ31 B alloy together with good formabil- [ ] ity and corrosion resistance but slightly poorer welding characteristics. AZ80 A, ZK60 A-F, and ZK60 A-T5 alloys are used where the maximum in physical properties is required. AZ80 A alloy possesses fair corrosion resistance but with formability and welding characteristics inferior to' the other alloys. ZK60 A-F and ZK60 A-T5 alloys, while only recently offered for com¬mercial use, are finding favor due, to the higher permissible extrusion rates. These alloys possess greater toughness than AZ80 A alloy and, while of moderate formability at room temperature, are very formable at 300° to 500°F. The major portion of tubing and hollow shape production at the present time is in AZ3I B alloy. Magnesium alloy tubing is commercially available in the as-extruded condition or, in the case of ZK60 A-T5, in the as-extruded and aged

Jan 1, 1951

By F. R. Koeberlin

ABOUT thirty miles south of the port of Coquimbo, Chile, nestling in one of the western outliers of the main Andes range, lies the little mining town of Andacollo, a place whose history and traditions make up one of the most romantic pages in the life story of this southern republic. The beginning of Andacollo is shrouded in the penumbra of the pre-Columbian era, but its first mining activity probably dates from about the years 1440 to 1460. It was in the middle of the fifteenth century that the Inca Tupac-Yupanqui, grandfather of Atahualpa, conquered this part of Chile. His domain extended even as far south as the present site of Santiago, and perhaps farther, but was maintained with increasing difficulty against the fiercely independent and indomitable tribes of Araucanian Indians of the South.

Jan 1, 1938

By Williams, J. A.

THE Alaska Juneau mine has been developed through an adit driven at the elevation of the top of the mill and all mining is done above this main haulage level. As a result of wholesa1e"mining operations about 11,000 tons rock containing one dollar' per ton in gold is, hauled to the. concentrator during every 24 hr. Due to the method of mining, whereby a system of oreways delivers-the.ore direct from the stope to the bottom level of the mine, no tramming of ore is done on any of the upper levels. However, ;in doing exploratory drifting and crosscutting on the upper levels, the broken material is trammed by hand in 1-ton 18-in. gage cars to a nearby raise connecting with one of the several oreways. This constitutes the only tramming operation except that on the main level.

Jan 1, 1931

By H. A. MEGRAW

THE meeting of the A. I. M. E. at Wilkes-Barre, Pa., Sept. 12 to 15, inclusive, celebrated the fiftieth anniversary of the Institute. It was at Wilkes-Barre, in 1871, that the foundation was laid for the great institution that now includes in its roster the greatest names. in mining engineering in every civilized country of the world. The founders of the Institute, with rare prescience, established a common ground upon which all mining engineers, whatever particular branch they might consider most pertinent, could stand securely, assured of a deep-seated interest from their brethren similarly minded in other localities. So wise and clear was the vision of the founders that every engineer connected with mining has found it beneficial, not to say indispensable, to maintain his connection with the Institute and to increase his technical enthusiasm through the medium of the valuable technical publications. The little coterie of 1871 has grown to a strong body of more than 10,000 members in 1921, reflecting the glory of the founders in the record of the accomplishments written on the pages of the fifty years of the

Jan 1, 1921

By John Gross

The building of reverberatory furnaces (Fortschaufelungsofen) where ordinary brick, fire-brick and iron are comparatively cheap, is quite a different matter from the building of such furnaces in isolated camps, where proper material is only to be obtained at high cost and with long delays. Time is always a large factor in metallurgical operations, and the metallurgist may find himself in a position where it becomes necessary to erect apparatus and have it running in less time than it would take to obtain material from outside. It is here that he must make use of makeshifts. In Mexico, one of the most important of these is the alluseful adobe. Employed from prehistoric times, it still has its sphere of application in a surprisingly large number of instances requiring an article that can be quickly and cheaply produced. It is quite possible to erect serviceable reverberatory furnaces with no other materials than adobes, stone and wood. The old Mexican smelting shaft-furnace was an example of what can be done with adobes, and the large number of ruins of this class of furnace scattered through the mining districts of Mexico are silent testimony to the genius of a people who demonstrated their capability of adapting material at hand to their needs. The present paper will describe briefly the construction of an adobe reverberatory furnace which is giving good results, can be quickly erected at a low cost, and, if properly built and handled, will last a long time. The material being simply sun-dried, it naturally follows that the construction must be quite heavy. The adobes should be evenly made, with just sufficient straw to hold them together, and not too large in size (9 in. wide, 18 in. long and 4 in. thick

Jan 1, 1902

By Sheldon P. Wimpfen

RESEARCH is undertaken to find out what must be done when what we are doing now is no longer adequate. To accomplish this end, researchers apply the truths of nature to industrial evolution. A survey conducted with the co-operation of 58 universities and colleges offering degrees in mineral engineering was the basis for the table accompanying this article. This survey was undertaken with the object of presenting to faculties and student bodies, as well as to industry, all available information on what action the educational institutions of the country have taken to provide the properly trained researchers so vitally needed. A hoped for result is that the great variety of opportunities available will encourage some undergraduate students to continue in their field beyond attainment of a B.S. degree.

Jan 1, 1947

By Mehmet Guney

At the Armatcuk mine in Turkey, various modifications of sublevel methods have been tried during the last decade in an effort to eliminate gob fires, dangers from roof falls, and surface subsidence, and also to increase extraction efficiency. From the experience thus gained, it was decided that the most likely system to give maximum benefits, considering the existing geological conditions and coa1-seam characteristics, was hydraulic stowing. This paper examines trends in the working techniques of hydraulic stowing and discusses the favorable results and technical problems that the method produced at Armutcuk. The Armutcuk mine, a subsidiary of Eregli Coal Mines (EKI), produces 1300 tons of run-of-mine coal daily from thick (about 10-90 ft) and highly dipping (about 50-90°) coal seams. The coal is highly volatile with good coking properties that make it highly suitable for industrial use. Most of this coal is used in the iron and steel industry at Eregli on the Black Sea coast. Complete recovery of the coal is of vital importance to industrial development and progress. Initial coal extraction was carried out by means of a sublevel mining system modified to accommodate local geological conditions and coal seam characteristics. This method is similar to that employed in metalliferous mines. Several problems arose from the application of the method, one of them being the prevalence of gob fires which caused periodic shutdowns in some sections. To achieve maximum coal extraction with minimum dilution, to eliminate gob fires and surface subsidence, and to reduce fatal accident rates, a decision was taken to change from this method to a hydraulic stowing system. The pres- ence of large deposits of conglomerate and sandstone on the surface contributed to the decision to employ this new method. Although hydraulic stowing practices have been carried out in America and Germany, Upper Silesia may, so far as coal is concerned, be considered the birthplace of the method. Here the process was adapted to thick coal seams on a large scale to reduce dangers from gob fires and damage from surface subsidence. Today, the mining system is not only widely used in the coal mines of France, the Saar, India and Poland, but has also been successfully applied to the iron ore and potassium salt mines in Russia and Germany. LOCATION AND HISTORY The Kandilli-Armutcuk coal field, the most western outcrop of the North Anatolian coal basin, extends for five miles along the Black Sea coast (Fig. 1). The Armutcuk Mine is situated on the southern boundary of the coal field about 40 miles from Zonguldak and about 12 miles from Eregli. The history of coal mining in the North Anatolian coal basin goes back more than a century. Mining commenced on a small scale in the Kandilli-Armutcuk coal field in the late 1880's, and from this time until nationalization in 1940 the mines were operated by private Turkish and foreign interests. In 1940, Eregli Coal Mines was established to takeover the management of these enterprises. The Armutcuk Mine was developed for the first time in the mid-1940's. Since then it has been in continuous production and it now produces an annual 440,000-ton run-of-mine output from which 320.000 tons of salable coal is obtained. MINE GEOLOGY The carboniferous inlier of the Kandilli-Armutcuk coal field crops out over an area about three miles long and one mile wide. The major part of the inlier consists of the Namurian formation with only a relatively small area of Westfalian-A visible on the surface (Fig. 2). The Namurian formation, which has no exploitable coal seams in the Armutcuk Mine, consists mostly of arkose sandstones and black shales often having

Jan 1, 1969

By John S. Brown

The northeastern United States embraces that area of the Appalachian Mountains, and adjacent territory, beginning on the south at the Potomac River. It thus extends from the flat-lying Paleozoic terrane of the Appalachian plateau on the west, across the folded Paleozoics of the Great Valley and adjacent ridges (Paleozoic and Precambrian), over the Piedmont and New England metamorphic complex (mixed Paleozoic and igenous rocks), broken by the great Triassic rift remnants, onto the subdued coastal plain of Cretaceous and Tertiary sediments. Although not noted as a metal mining region, the area does contain numerous substantial and several outstanding mines, chiefly of the more prosaic metals, particularly iron, zinc, and copper, as well as many minor occurrences of these and a few additional items. These deposits occur to some extent in every subdivision of the area. The region to date (1966) has produced almost 500,000,000 tons of medium to lowgrade iron ore, especially magnetite, including ilmenitic magnetite; 50,000,000 tons of highgrade zinc ore; and 5,000,000 tons of lowgrade copper. In the past, it has yielded small amounts of chromite and nickel, and at present is a large producer of titanium. Precious metals are conspicuously absent, and so also are the Tertiary or Mesozoic igneous phenomena so commonly associated with mines of the West. Hence, a survey of the extensive mineralization · of this region should be instructive

Jan 1, 1968

By F. N. Speller

ASIDE from the Tuesday symposium on gases in metals, the Iron and Steel Division swung into action for the first time on the third day of the meeting with a discussion of iron and steel alloys. Dr. E. S. Davenport opened the discussion on Wednesday morning by presenting the paper written by himself in association with E. C. Bain and W. S. N. wiring on the equilibrium diagram of iron-manganese-carbon alloys. A written discussion by Mr. Scott showed qualitative agree- ment, but some quantitative disagreement. Messrs. Marsh and Sisco discussed the paper at length, pointing out non- agreement of certain conclusions with the phase rule. Dr. Krivobok, although differing with the authors on some points, stated that in his opinion the information collected would be valuable in the practical use of these alloys.

Jan 1, 1932

By J. C. Bayles

Jan 1, 1885