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By AIME AIME

READERS of a technical paper, or the audience if the paper is presented orally, judge the paper on several counts. The September 1940 issue of MINING AND METALLURGY contained an excellent short article by S. Marion Tucker en- titled "Are You Going to Present a Paper," which considered the general subject of presentation. In it Dr. Tucker referred to the large number of poorly prepared and badly delivered papers that are presented annually before the large number of technical and other societies that meet regularly, and he stressed the point that good delivery, length of paper, content, and composition are of great importance. All of Dr. Tucker's points were well taken; however, good illustrations are equally important in explaining certain phases of some papers.

Jan 1, 1941

By V. F. Swanson

At the AIME meeting in Tampa in Oct. 1966, an empirically developed equation was presented which allowed the calculation of free settling velocity for any sized particle: 1 [ ] This equation requires the use of two parameters a and p which are coefficients derived from boundary layer theory.2 It was possible to develop values of a and p for several minerals by back calculation of published data. The original equation had one major flaw. When the fluid density exceeds the density of the solids, the solution to the equation becomes imaginary. A flaw was indicated also by the fact that galena and sylvite both having cubic cleavage, did not have similar values for a and b. Galena gave calculated values of a = 1.082 and g = 3.11, while sylvite gave values of a = 1.870 and p = 2.56. These flaws prompted further study of the equation, resulting in the following empirical modification: [ ] It is obvious a real solution of the equation is possible for all values of ps and p. When PL > PS, V is negative, indicating that the particles will rise against the attraction of gravity. The validity of the modification is borne out by the fact that when values of a and p were back calculated for galena and sylvite using the modified equation, both minerals gave values of a = 1.038 and p = 3.01. With the modification shown in Eq. 2, Newton's friction factor becomes [ ]

Jan 1, 1976

By J. A. Wilcox

A NEW LINE of specialists has arisen as a result of the trend toward labor socialization and collectivism in all branches of industry. These men are the ones who will govern the destiny of many companies and the labor policy of our government in coming years. They must be men of integrity and of rather exceptional qualifications; men who can foresee the trend of labor relations with business, and who are willing to sacrifice the immediate fruits of technical training for manual labor and study. They must take their place in industry, not with the idea of following the orthodox line of advancement, but knowing that they must stay at the bottom until they have learned to understand the viewpoints, the work, the advantages and the disadvantages of each classification of labor. They must not be of a radical nature or become easily biased, and they must study. You will say I am looking for a superman and in one sense that is true, but the business man and our government are both in the market even now for this type of man, and with the proper training and background, many of our young technicians can readily enter this field of work.

Jan 1, 1942

By J. A. Retty

HOLLINGER CONSOLIDATED GOLD MINES LTD., through two subsidiary companies, has the exclusive right to prospect in two contiguous areas in central Labrador. This paper presents the results of the mineral exploration that has been conducted in these areas to date. One of the subsidiaries of Hollinger. the Labrador Mining and Exploration Co. Ltd., under an agreement with the Newfoundland Commission of Government, holds an area of approximately 20,000 sq.mi., which comprises the western portion of Newfoundland-Labrador and includes the upper basins of the Hamilton and Naskaupi Rivers. (The main area of the deposits so far discovered may be located on a map at about 67° west longitude and 55° north latitude.) The other subsidiary of Hollinger, Hollinger North Shore Exploration Co. Ltd., has licensed from the Province of Quebec an area of approximately 3900 sq.mi. lying directly north of the Newfoundland-controlled area at the headwaters of the George, Whale, and Swampy Bay Rivers. The M. A. Hanna Co., large iron-ore operators of the Lake Superior region, are participating in the project. With the exception of the years 1940 and 1941, field work has been conducted in the Newfoundland area since 1936, and in the Quebec area since 1939. Hollinger assumed the management in 1942. The field base is at Hollinger Lake, some 300 miles north of the tidewater base at Seven Islands, Quebec, which, in turn, is just west of the mouth of the Moisie River, on the Gulf of St. Lawrence. Air transportation is used exclusively to service the operation.

Jan 1, 1945

By R. G. Knickerbocker

A STURDY and consistent expansion of the metal industry occurred in 1947 exemplified by an increase of approximately 30 per cent in steel consumption over 1946. For this major reason, ferroalloy metals have seen their most useful and important peace-time year. The current domestic rate of consumption of high-grade ferroalloy ores, together with added consumption of new foreign producers as well as for eign nationals' restrictions on high-grade exports, makes very evident the increasing difficulties of obtaining sufficient high-grade ores. This accentuates the need for new and less expensive methods of production of ferro-alloy metals of higher purity from lower-grade domestic resources. As an important factor in preparedness, procurement of these high-grade, -critical ferroalloy minerals and metals for our nation's stock piles is a most important task. Also, this stock-piling can be the means of supplying incentive for the industrial development of the new metallurgical processes and plants necessary for the recovery of ferroalloy metals from our domestic low-grade deposits.

Jan 1, 1948

By T. L. CONDRON

DURING the past fourteen months, this committee has had under consideration and study the subject of the licensing or registration of engineers. The fifteen members of the committee as appointed by Council, were selected from thirteen states, viz., Connecticut, New York, Pennsylvania, Ohio, Georgia, Louisiana, Illinois, Missouri, Iowa, Minnesota, Colorado, California and Washington, and therefore represent practically all sections* of the United States, as well as mechanical, electrical, mining, hydraulic, municipal, sanitary, railway and' structural engineering, and also colleges of engineering. The first work of the committee was to investigate the general subject and to collect, so far as possible, avail¬able material bearing upon the subject in hand,. in-' eluding opinions from many engineers as to the need or desirability of legislation, as well as copies of all state laws passed and proposed, having to do with licensing or registration of engineers, architects and surveyor, This preliminary investigation disclosed that very pronounced views were held by engineers throughout the country, both for and against state licensing or registration. The general sentiment one year ago was more opposed to such measures than it is today. The older members of the profession did not as a rule favor licensing nor did they feel there was need for state regulation of engineering practice, while among the younger men there was a feeling that licensing or registration by the states would add prestige to professional engineers and in many ways benefit -the profession, as well as individual engineers.

Jan 1, 1920

By F. Keller

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

Jan 1, 1946

By AIME AIME

IT IS impossible in this short sketch to give a detailed description of each part of the plant at Bethlehem, therefore, only such facts will be touched on as are necessary to give a general idea of the works. The extent of the plant, and the fact that the units making up the various departments are located in different parts of the works, make it impracticable to mention the departments in any regular order with regard to their location. They are, therefore, mentioned approximately in the order of their relation to each other with reference to their functions in the making of the various products.

Jan 1, 1924

By Herbert Hoover

THERE is one problem of the new administration that has received the attention and thought of the organized engineers of America for many years past. This is the problem of the reorganization of the Federal Government. The, inadequacy, the wastefulness, and the inefficiency of our federal organization was evident, enough under pre-war conditions. These inadequacies, these inefficiencies, these wastes were exhibited to the country during the war at the cost of millions. Congress has placed the problem in the hands of a very able Congressional Joint Committee, but if this Joint Committee succeeds in securing the imminently necessary results it will only be by full insistent support to it by public opinion. Many attempts have been made at reorganization before but all, of them have gone to the same crematory-the interminable differences in opinion among the executive and legislative officials over details.

Jan 1, 1921

By E. A. Holbrook

IN view of what has happened in - the past three years, it seems incredible that industrial corporations continue to write to engineering and mines schools for "promising members of the graduating class," or, indeed, that they even send representatives to the colleges to interview engineering graduates. Certainly, by this time, every company should be aware of the fact that recent engineering graduates are almost nonexistent and the number is not likely to increase within the next several years. At the February, 1945, annual meeting of the Local Section delegates of the A.I.M.E. in New York, W. B. Plank, professor of mining engineering at Lafayette College, summarized well the situation of the colleges by titling his talk "The Lost Generation of Engineers."

Jan 1, 1945

By AIME

BILL BREWSTER was a natural for the steel business. His family lived at Iron Mountain, Mich., when Bill was born on June 14, 1889, so that he had iron in his blood. Always he has looked toward the finished product, rather than the raw material, so that it was a fore-gone conclusion that he should work toward the steel end of the business. After preparing for college at Hotch-kiss Academy he entered the Sheffield Scientific School of Yale University from which he graduated in 1910 with the degree of Bachelor of Philosophy. No reunion of his class would be complete without Bill Brewster. Unlike many of us who try several jobs before settling down, Bill shot straight for the mark. After a summer's work at Iron Mountain, making sure of his background in the production of the raw iron ore, he entered the employ of Wisconsin Steel Works of the International Harvester Co. in September 1910 and has been there ever since. It wasn't much of a job to start with, just a laborer in the billet dock department, but soon there was an opening in the blast-furnace department, where he started as superintendent's clerk in December 1910.

Jan 1, 1946

By Philip D. Wilson

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

Jan 1, 1944

By C. L. HUNTZINGER

THE mine here described is in the Witbank district, a coal area of the Transvaal, about 100 miles north- east of Johannesburg. and is owned by the Witbank Colliery, Ltd. The plant has a capacity of 4000 tons per eight hours, and prepares five sizes of coal. The coal seam lies at a depth of about 200 ft. below the surface, and is reached by an inclined shaft sunk at an angle of 18° with the horizontal. Although the thickness of the coal seam varies from 10 to 14 ft. or more, only about a 7-ft. bench is mined. Mining is by the hord and pillar system. Bords are driven 18 ft. wide, with pillars measuring 18 ft. square. The mine is laid out into four sections, each sewed by a main haulage way from the shaft. Arc-wall machines are used for cutting the coal. but all loading is done by hand. Native labor is employed under the supervision of white miners, who do the required blasting. The workings are practically free from gas and water, and very little timber is needed.

Jan 1, 1931

By A. T. Churchman

The deformation modes of rhenium have been identified as those typical of the hexagonal metals, titanium, zirconium, and beryllium whose c/a ratios, in common with rhenium, are less than ideal for close packing. Slip is observed on (1010), (1011), and (0001) planes and twinning on (1121), (1122), and (1012) planes. The very high rate of work hardening is believed to be associated with intersecting partial dislocations on two (1010) systems which can combine to form sessile barriers. If the stacking fault energy is low, as postulated by Seeger, these barriers should be strong and not easily bypassed by cross slipping. Such an explanation could also account for the very small temperature dependence of the yield stress which was observed. RHENIUM is interesting scientifically as a member of the group of high melting point hexagonal metals: titanium, beryllium, and zirconium with a c/a ratio less than that for ideal close packing. Unlike them, however, it work hardens at a very high rate. This rate is greater and continues to a much higher degree of deformation than for nickel, normally considered to have a high rate of work hardening. This paper presents experimental observations on the modes of deformation of rhenium and, by comparison with other hexagonal metals, some speculation on the cause of the high work hardening. MATERIALS Johnson, Matthey rhenium powder of both 99.9 pct and 99.5 pct purity, see Table I, was compacted at 10 tons per sq in., part sintered at 1350°C in vacuo, and finally arc melted in a "gettered" argon atmosphere arc furnace to produce small buttons. Little difference was observed in the as-cast hardness or working down behavior of the two purities suggesting that either silicon and potassium do not have a significant effect on the working properties of rhenium or they were lost during arc melting. SPECIMEN PREPARATION The cast structure was broken up by cold-rolling with inter-stage annealing at 1600o or 1800°C in a vacuum high-frequency furnace using a tungsten susceptor. Strip for tensile testing was taken from two thicknesses of material 0.011 and 0.064 in. The former with intermediate anneals at 1800°C had a grain size of 900 grains per sq mm, while the latter with inter-stage annealing at 1600°C had a grain size of 3600 grains per sq mm. A coarse grain size was obtained by secondary recrystallization in a half button cold-worked by 30 pct reduction. Annealing times of from half an hour to several hours at 2200° to 2600°C in a "gettered" argon atmosphere arc furnace1 resulted in grains of up to 2 mm diam.

Jan 1, 1961

By Y. Nakada, E. J. Fasiska, A. S. Keh, L. Zwell

DURING an investigation of solid-solution hardening of nickel by carbon,' we found that there were no reliable data on the dilating effect of dissolved carbon on the unit cell of nickel. Bernier2 reported an increase in lattice parameter of nickel (3.523A) when an unknown amount of carbon was introduced into solid solution (3.536A). Similarly KG, Tsien, and Misek3 found an increase from 3.523 to 3.531A when nickel was carburized. strong4 studied the variation of nickel lattice constant as a function of dissolved carbon. However, in his case carbon was introduced into nickel by solidifying the melt at 65 kbar. Therefore, his carbon concentrations were much above the highest equilibrium solubility limit5 (2.7 at. pct C at 1 atm). Knowledge of the lattice mismatch between solute and solvent is essential in understanding the mechanism of solid-solution hardening. Therefore, we decided to determine the dilation of the nickel lattice by carbon under the more usual conditions of atmospheric pressure. The material used was Inco Electrolytic Nickel of 99.95 pct purity, as specified by the supplier. The impurity contents in wt pct were: Fe, 0.01; Cu, 0.01; Co, 0.03; 0, 0.005; C, Si, S, N, trace. To this base material various amounts of AUC-grade high-purity carbon were added during vacuum induction casting. Ingots, 2 in. in diam, were heated in a muffle furnace at 1000°C for i hr., hot-rolled to 1/2-in. thickness, and quenched into brine. All ingots with carbon concentration greater than 0.98 at. pct were enclosed in a cast iron box during the heating to minimize decar-burization. Small pieces were then either swaged down to 0.028-in.-diam wire or cold-rolled to 0.010-in.-thick sheets. After the final cold reduction in area of 50 pct, the specimens were recrystallized by heating in evacuated capsules at 1100°C for 60 to 80 sec and then quenched into brine. The final grain size was 50 to 100 µ. The carbon contents of the alloys, Table I, were determined by a combustion method

Jan 1, 1969

By Allan J. Clark

THE September issue of MINING AND METALLURGY might almost have served as a review of the advances in the metallurgy of gold during the current year. In addition to a scholarly article by F. W. Bradley, there were able descriptions by W. W. Bradley and W. F. Boericke of the methods followed in California and in Ontario. Considered together, the two last-named articles indicate the many possible combinations of flotation with one or more of the older processes. This, the prominence of flotation as an aid in the beneficiation of gold ores, is probably the most striking of the year's developments. It would perhaps be nearer the fact to say that the year has not been marked by the gold metallurgists' discovery of the flotation process, but rather by the flotation merchandizers' discovery of gold metallurgy. I say this because native gold was floated successfully more than fifteen years ago, and a reference to these results was published six years ago.

Jan 1, 1933

By NILS DANIELSEN

THE name of Swedish charcoal iron will probably bring to the memory of many old consumers an extremely tough and ductile iron which was formerly used in considerable quantities for common blacksmith purposes. To-day very little of this iron goes to such kind of work. Swedish charcoal iron is merely a speciality which is chosen whenever its remark¬able properties can be utilized. By giving a rough sketch of the manufacturing process of Swedish charcoal iron, the character of the iron, its weak as well as its strong points will more easily be understood. Swedish charcoal iron is a wrought iron also known in the United States under the name of Norway iron and Swedish Lancashire iron. The name Norway iron seems to have been attached to the product for the reason that in the earlier days it was generally brought into the States by Norwegian ships. However no iron of this kind is now made in Norway. The reason for the name Swedish Lancashire iron is that the manufac¬turing process emanated from Lancashier in England, the method being generally adopted in Sweden in the years 1831-1850. Today this iron is, with the exception of one plant in the United States, made in no place in the world outside of Sweden.

Jan 1, 1924

By E. L. WOOD

IN ATTEMPTING to summarize briefly the reconstruction of the Hecla plant since the fire, three important facts must be held in mind; namely: a hurry-up job with the shadow of an insurance company in the background; restriction of working space in the narrow Burke Canyon; and building two-thirds of the plant on a filled area. Construction work was carried on without interruption through the winter season. These adverse conditions have contributed many obstacles not ordinarily encountered in mining work. The first problems immediately after the fire were organization and policy; the-former to create an efficient construction crew out of a mining organization; the latter to determine the type and extent of surface plant to be built. The new crew was organized from a nucleus of mine employees, 25 per cent. of the old crew remaining for construction work. Permanent fireproof buildings were decided upon, the general arrangement of the new plant to be similar to the old one as far as possible, at the same time enlarging it 100 per cent. in anticipation of the demands which would be made upon it when the Star Mine began operating. Cleaning up the wreckage was a big job, the extent of which is indicated by the fact that 30 carloads of scrap iron and steel were moved off the property. In re-establishing transportation facilities at the plant, a previous disadvantage of a steep grade on the high line was obviated by excavating 1600 yd. of solid rock; the fire having destroyed all town buildings below, made this work possible.

Jan 1, 1924

By W. S. Ayres

I. INTRODUCTION. THIS cavern was discovered Oct. 22, 1904, by Mr. Charles H. Deutschman, in company with whom I made, May 29 to June 3, 1905, at the request of Mr. Howard Douglas, Superintendent of the Canadian National Parks, the first exploration of it for the Canadian government. The results were stated in a paper, orally presented, with lantern-views from my photographs, at the British Columbia Meeting of the Institute, Victoria,, B. C., July 5, 1905.* The present paper embodies also the results of a second examination, made Oct. 25 to 29, 1905. The accompanying map, Fig. 1, will serve as a guide to the following description. II. LOCATION. The cavern is situated at snow-line, at the head-waters of Cougar creek, on the west slopes of the Selkirks, about 2 miles north from Ross Peak water-tank, and 5.5 miles west from Glacier House, on the main line of the Canadian Pacific Railway. It was then reached by an arduous climb from the water-tank, up the ravine of Cougar creek, for 8,000 ft. (2,000 ft. of altitude) over rock- and snow-slides, and through a thick tangle of alders. But an easy and very picturesque trail has, during the past summer, been opened by the government from Glacier House. Figs. 2, 3 and 4 represent views, not heretofore published, of the grand scenery of this region, so rapidly becoming the-object of attraction to thousands of tourists from all parts of the world. These views, as well as those shown in. Figs. 5, 6, 7, 8

Jan 1, 1907

By Sheldon P. Wimpfen, Ralph H. Sweefser

FOR centuries the pumping of water has been one of the chief problems to be overcome by the persistent men who win the mineral wealth of the world. Profitable operations have often been forced to suspend activities as the mine penetrated well below the water table or when sudden rushes of water were encountered. To operate below the local water level requires continuous pumping equal in volume to the amount of water flow¬ing into the mine workings. Often the water to be removed exceeds the tonnage of valuable material produced. To be above local water level is a valuable asset. Modern mining practice permits nothing short of the extraction of the last pound of profitable ore from a mineral deposit. In the days before the development of mechanical and electrical power as we know it today. water in any quantity was a major

Jan 1, 1948