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By W. C. Elli, M. E. Fine

YOUNG'S modulus of elasticity in metals ordinarily decreases with rising temperature. The range of the thermoelastic coefficient at room tem- 1/E dE/dT perature (temperature coefficient of modulus, is illustrated1 by the values for tungsten and hard-drawn aluminum, —95 and —1220x10-6 eg C-1. However, a nearly zero thermoelastic coefficient is observed in some ferromagnetic alloys over a limited temperature range. In these alloys, as the temperature is raised, an increase in modulus arising from loss of ferromagnetism compensates the normal decrease. Iron-nickel alloys containing 36 to 52 pct Ni behave in this manner. In the present investiga- tion, the dependence of the modulus and thermo-elastic coefficient on cold working and annealing were studied in iron-nickel alloys in this range of nickel. Although these alloys, when fully annealed, have a coefficient near zero over a very small temperature interval, the temperature range of low coefficient can be extended greatly by straining and then stress-relief annealing. The modulus of face-centered cubic iron-nickel alloys annealed at 1000°C does not vary linearly with composition at room temperature but, as shown by the solid line of fig. 1, from Koster,' is minimum at 40 pct Ni and maximum at 87 pct Ni. The modulus increases with applied magnetic field but retains the minimum near 40 pct Ni. Schematic change of modulus with temperature for three compositions is shown in fig. 2.'. ' With increasing temperature, the slope becomes less negative, goes through zero (temperature of minimum modulus for the alloy), becomes positive, and resumes its normal negative value above the Curie

Jan 1, 1951

By Joseph W. Roe

MANY questions arising in the work of the mining engineer may be solved quickly and with sufficient accuracy by the methods of descriptive geometry; but, unfortunately, this subject is more often considered from a mathematical view-point than as an effective tool. for solving practical problems. Some of the principles involved are merged into the ordinary operations of mechanical drawing, and are used unconsciously by the engineer in his every-day work. The rest are stowed away on the book-shelf with his forgotten or rarely-used college text-books. One reason for this condition of "innocuous desuetude " may lie in the unfortunate and often cumbersome notation which it has been found necessary to introduce. If some of these principles can be recalled to the engineer's attention in terms of every-day use they may prove of practical bearing. Recently, in talking with several mining engineers, I used some of the drawing-room methods of a machine-designer, to the evident surprise of those around me. These men were perfectly familiar with the methods, but their application to mining-work had not occurred to them. At their suggestion the present paper is offered, not in any way as a treatise, but merely to suggest a certain point of view, in hope that it may lead others far more familiar with mining-problems to pursue the subject further. I. To FIND THE STRIKE. As the simplest and most fundamental problem, let it be required to find the strike of a vein when the location and elevation of three points on the outcrop are known. It will be assumed for the present that the vein is a plane.

Mar 1, 1910

By H. Hubert

THE first attempts at direct utilization of blast-furnace gas in engines were made in 1895. For a considerable time the gas had been burnt in Cowper stoves for heating the blast for the furnace, and under the boilers which supplied steam to the blowing-engines, and others serving the furnaces. It was natural, therefore, that the idea of directly employing it in gas-engines should have occurred simultaneously to several engineers, notably to Lürmann and to Lencauchez, who had pointed out the blast-furnace as a powerful -gas-producer. Nevertheless, nowhere had any attempt been made to apply it to this purpose up to the end of 1894, when Thwaite proposed it to Mr. James Riley, of the Glasgow Iron & Steel Company. About the same time investigations were being made in Belgium and in Germany, independently of Thwaite's experiments, which were not generally known on the Continent. The industrial world, which up to that time had hardly favored the idea, had thus been gradually prepared to receive it. The gas-engine, long restricted to small sizes and dependent upon the use of an expensive fuel obtainable only in large centers, now began to make headway. At the Paris Exhibition of 1889 two engines of 100 h.p. were shown and excited much interest among engineers. One had four cylinders, and was made at the celebrated works of the Deutz Company, and the other was a single-cylinder engine, exhibited by two French designers, Messrs. Delamare-Deboutteville and Malandin. In the meanwhile the design of gas-producers had made important progress, completely freeing the new engine from its

Nov 1, 1906

By C. BARING HORIVOOD

(Chattanooga Meeting, October, 1908.) THIS paper is intended, in the light of recent investigations, to call attention to some of the essential features of good practice in sampling and mine-valuation. Mine-sampling may be divided broadly into two classes : (1) development-sampling and computation of ore-reserves; and, (2) stope-sampling and estimation of stope-values. DEVELOPMENT-SAMPLING. It is with development-sampling only that this paper deals-the term development being taken to mean the opening-up of a mine by cross-cuts, drives, connections, etc., preparatory to actual extraction of the ore for milling. In development-sampling the work of the sampler and the consequent estimation of the probable value of the mine or portions of the mine, as the case may be, cannot be verified until a later period, when the ground thus sampled has been exploited; hence, extreme care and accuracy are essential. Moreover, the development-sampler has to foresee and allow for contingencies which may arise when stoping is started. It follows that the sampling, in development-work, demands familiarity with the conditions likely to be encountered later in actual mining. In stopes, on the other hand, sampling is clone under actual working-conditions, and the sampler's valuations are immediately checked by the gold-output, or in some cases by a second sampling of the broken ore. A stope-sampler therefore need not be an experienced miner, though he should possess sound technical training and work accurately. Should he be somewhat inexperienced, be soon has his errors discovered for him, and learns to avoid them. Taking these facts into account, it is obvious that a mining company employing two or more samplers should

Jan 1, 1909

By FREDERICK J. ALCOCK

THE high prices which lead and zinc have commanded during recent months have given a great impetus to search for workable deposits of these metals, and there has accordingly risen a demand for information about deposits which have been worked in the past and which might possibly be opened up anew under these more favorable conditions. Production of zinc and lead in Canada has been on the increase during the last few years. In 1924, 175,- 485,499 lb. of lead with a computed value of $14,221,- 345 were mined. Of this, 96 per cent. was produced in British Columbia, 3 per cent. in Ontario, while Quebec and the Mayo district of the Yukon accounted for the remaining one per cent. During the same year the production of zinc amounted to 98,909,077 lb.. valued at $6,274,791. Of this 96,000,069 lb. were produced in British Columbia and the remaining 2,909,008 in Quebec. The large producer of zinc and also of lead is the Sullivan Mine at Kimberley, B. C. In comparison with the Sullivan, the deposits which are known to occur in eastern Canada are relatively small. Two, however, the Kingdoll lead mine at Galetta, Ontario, and the Tetreault zinc property at Notre Dame des Anges, Quebec, are steady producers. The object of this paper is to describe briefly these and other deposits of eastern Canada, to show their relation to geological events and to point out what are the chances of any of those which are idle at present developing into active producers or what are the possibilities of new deposits being discovered.

Jan 1, 1926

By AIME

TITANIUM-RICH ilmenite deposits, situated in the Allard Lake area in Quebec some 400 miles down the St. Lawrence River from Quebec City and 28 miles north of Havre St. Pierre on the north shore of the Gulf of St. Lawrence, are undergoing an intensive development program by the joint efforts of the Kennecott Copper Corp. and The New Jersey Zinc Co. Easily accessible ore, amounting to about 125 million long tons and carrying from thirty to forty per cent titanium oxide, has been delimited. Plans are being made for construction of an electric smelter at Sorel, on the south bank of the St. Lawrence midway beween Montreal and Three Rivers, which will produce 650 long tons of high-grade titanium slag and 500 long tons of iron per day from 1500 long tons of ore. Occurrence of ilmenite ore in this area has been known since J. A. Retty reported his geological work in the lower Romaine River area for the Quebec Bureau of Mines in 1941. In this report Dr. Retty mentions the presence of anorthosite rocks, some of which were rich in ilmenite. Claims were staked by several interests but the small showings and complex metallurgy were too formidable for any organization not adequately equipped with capital, metallurgical knowhow, and market outlets. However, Kennecott became interested and through a newly formed Canadian subsidiary, Kennco Explorations Ltd., options were taken up under the direction of A. H. Robertson. An area of 300 square miles was traversed in the summers of 1945 and 1946. During 1946 and 1947 geophysical and diamond-drill prospecting disclosed a num-

Jan 1, 1948

One session of the annual meeting of the American Society of Civil Engineers-the first since this society became a Founder society with representation on the Board of the United Engineering Society-was held on Jan. 17, 1917, in the Engineering Societies' Building. Mr. Charles F. Rand, Past-President of this Institute, and President of the United Engineering Society, welcomed the new Founder society in the following words: "As one who has looked forward very earnestly to this clay, and who has made a modest effort in favor of the new arrangements, it is a peculiar satisfaction to be the representative of the Trustees of the United Engineering Society and to welcome you on the occasion of your first meeting in this building in which you now own' a quarter interest. "'As this is your annual meeting, I cannot take your time for extended remarks, yet it seems proper that I should call attention to a few facts respecting the United Engineering Society, with which you are now identified. "The United Engineering Society exists for the purpose of holding the legal title to certain of the property of the societies of Civil, Mining, Mechanical and Electrical Engineers and to act for them in certain matters. "The value of its property, including real estate, the Library and the Reserve and Endowment funds, exceeds two million dollars, all free and clear. "The total membership of the four Founder societies is 29,000 and the membership of associate societies is 23,000, making a grand total of 52,000 engineers who now have headquarters in this building.

Jan 3, 1917

By Charles D. Walcott

The following acts of the Directors are reported for the information of members At a meeting held June 20, 1907, Dr. Charles D. Walcott, Director of the U. S. Geological Survey, Washington, D. C., having been recommended by unanimous vote of the Council, was unanimously elected an Honorary Member of the American Institute of Mining Engineers, in recognition of his personal services to American geology, and of his generous co-operation with this Institute, to the Transactions of which he has not only himself made valuable contributions, but has also encouraged the preparation of such contributions by the members of the U. S. Geological Survey under his charge, his liberal policy in this respect having gone so far as to permit the preliminary publication by the Institute of important results reached by the geologists of that Survey, even before their final and full publication as public documents. This wise and generous course has not only brought the U. S. Geological Survey into intimate and sympathetic relations with the mining industry of the world, but has also enriched the Transactions of the Institute, especially in the department of the science of ore-deposits, with many valuable papers. At a meeting held Jan. 14, 1908, Mr. Charles Kirchhoff was unanimously re-elected a Trustee of the United Engineering Society, to serve for a second term of three years. At a meeting held Feb. 18, 1908, directly after the adjournment of the annual meeting of the Institute, the following officers were elected for the ensuing year: President, James Gayley: Vice-President, James Douglas; Secretary, R. W. Raymond; Treasurer, Frank Lyman.

Mar 1, 1908

By Nicholas J. Grant, H. C. Chang

TRANSCRYSTALLINE fracture surfaces of the cleavage type have been examined by microscopy and X-rays for several metals.' These investigations revealed that the fractured surfaces were not flat and invariably had cleavage and other deformation markings on them. On the other hand, the study of inter crystalline fracture surfaces has been limited. Perryman, in a recently published paper on the inter crystalline fracture of ß-brasses,' found that a thin layer of heavily deformed metal was invariably associated with these surfaces. Furthermore, the thickness of this layer was found to depend on the orientation of the grain boundary surface with respect to the applied stress. The mechanisms of grain boundary sliding and intercrystalline fracture have been presented in two previous papers,which described certain aspects of the deformation of a 20 pct Zn-A1 alloy. It is the purpose of this paper to present some observations on the structure of intercrystalline fracture surfaces and to correlate the structure of such surfaces with the mechanism of intercrystalline fracture. Experimental Techniques—The high purity 20 pct Zn-Al alloy was generously supplied by the Research Laboratories of the Aluminum Co. of America. Two sizes of specimen were used; the first had two parallel flat surfaces of dimensions 1x0.17x0.09 in. and the second was round with a 0.25 in. diam. A grain diameter of 1 to 3 mm was obtained by annealing the specimens at 1000°F for 24 hr. The specimens were then air cooled. The specimens were subjected to creep at 500°F and 2300 psi. The rupture times ranged from % to 3 hr, with one room temperature tensile test. It has been mentioned previous1y" that the intercrystalline fracture surfaces of this alloy, when tested under the conditions given above, are sharply defined. In the optical examination of the fracture surfaces, whenever possible, magnifications of at least X250 were used. The locations of the regions examined, both optically and by X-rays, were selected to give several fracture surface orientations with respect to the stress axis and to the specimen surfaces. This was possible for the X-ray studies since the grain diameters were large compared to the X-ray beam. A film to specimen distance of 3 cm, a 1 mm pinhole and Cr radiation were used for the Laue back reflection pictures.

Jan 1, 1957

Vol. 54 will be sent about February 1 to members who have paid their dues for the current year. Members who do not receive copies within a reasonable time are asked to notify the Secretary.

Jan 2, 1917

There are no authentic records of production prior to 1869, although various records report local production and use in 1853 and 1860. Tonnages in Table 68 for the years 1853-1868, both inclusive, are estimated. [ ]

Jan 1, 1942

By R. W. M. Lai

This paper presents a simple flotation kinetics model (Lai, 1981) along with a method of presenting the model in an informative graphical form. Examples are given for evaluating various flotation conditions and different ore types.

Jan 1, 1983

By SME

A regular feature of the December issue is the abstracts of graduate theses in the mineral industry field presented during the preceding year. The following abstracts were submitted for this second article in the series.

Jan 1, 1976

A regular feature of the December issue is to be abstracts of graduate theses in the mineral industry field presented during that year. The following abstracts were submitted for this first article in the series.

Jan 1, 1975

[Furnaces (see also Blast jurnaces) :-(Continued.) McGill, Nev., LI, 765. roasting: XLIX, 184, 188. Anaconda, Mont., XXXVII, 462, XLIX, 676. concrete hearths for, XLVI, 419. Crouse, XLVI, 413. gas, XXXVIII, 163. Heberlein, XXXVII, 634.]

Jan 1, 1918

PLANS are underway for the annual meeting of AIME, to be held in New York, February 17 to 21. The technical program includes meetings of all divisions of all three branches, Mining, Metals, and Petroleum. The bulk of the technical sessions will be held at the Statler Hotel, and the annual banquet will be held at the Waldorf-Astoria, Wednesday evening, February 20. The technical program of the Mining Branch activities is included in this issue. While it is not complete in every detail, it shows general interest groupings as well as subjects to be discussed. The program for each division is shown separately to facilitate following the activities of these special interest groups. Then, after a full scale and possibly somewhat strenuous technical meeting, a post-meeting feature will appeal to many of the members. A restful cruise to Bermuda and Nassau is offered at special rates to AIME members and friends. The schedule is a 3:00 pm departure from New York on the Queen of Bermuda on Saturday, February 23; arrival at Bermuda at 7:00 am Monday, February 25; arrival at Nassau at noon, Wednesday, February 27; and the trip ending again in New York at 9:00 am, Saturday, March 1. Rates begin at $202.10 per person, with higher rates depending upon accomodations desired. The base rate includes outside room with private bath and all meals, as well as Federal, Bermuda and Nassau taxes. Reservations for the trip should be made immediately through Leon V. Arnold, 36 Washington Square West, New York 11, who is in charge of arrangements.

Jan 1, 1952

By Mark C. Malamphy, Irnack C. Do Amaral

Four magnetic fleld balances and several spare magnetic systems were purchased by the Brazilian National Department of Mineral Production from the Askania Werke A. G., of Berlin, in 1932. Preliminary field tests on this new equipment showed one of the vertical component magnetic systems to be defective. A series of measurements designed to investigate the functioning of these instruments, and particularly the defective system, showed it to have an abnormally low magnetic moment, as compared to the satisfactory systems, and a high-temperature correction that was opposite in sign to that which would be expected for a noncompensated magnetic system. Since these systems were of the "temperature compensated" type, this condition indicated an accidental overcompensation. Attempts to correct for this overcompensation by readjustment of the compensating masses on the aluminum and Invar spindles failed because the distance by which the position of the masses could be shifted was insufficient. The temperature effect was reduced by this readjustment but was not entirely eliminated, as was to be desired. Theoretical deductions indicated that the defective condition of the system could be explained as due to three possible causes: (1) considerable loss of magnetic moment of the system; (2) increase in the magnetic temperature coefficient of the laminas; (3) dislocation of the component parts of the system caused by a shock experienced after it left the factory and before it was tested in Brazil. Later information received from the factory after examination of the returned system indicated that the third cause probably played the most important role. Temperature calibrations of the defective system for various positions of the counterweights brought out an important point, which it is believed

Jan 1, 1940

By Oliver B. Hopkins

During 1931 Peru maintained its position as the ninth oil-producing country of the world, with an output somewhat greater than that of Trinidad and Argentina, and considerably less than for Colombia and Mexico. Outside of the three old producing fields, there was little or no activity of importance; no new areas were brought in and no extensive wildcat drilling was done. On the other hand, the old fields continued to produce at a rate only slightly below normal and such restriction as existed may be attributed to market and not to field conditions. Political disturbances during the spring led to several strikes in the field, causing temporary suspension of activities there. However, such troubles were of short duration and no permanent loss of production was sustained. The production in barrels during the past three years for the three coastal fields of Peru has been as follows: The oil industry in Peru is relatively old; 29 wells were drilled in the Negritos area between 1888 and 1898. Prior to 1900 the production was relatively insignificant but from 1900 until 1929, it has slowly but steadily increased to a maximum annual production of over 13,000,000 bbl. The potential production of the fields since 1939 has exceeded the production of those years; the actual production has been controlled by market conditions. The production of the property of the International Petroleum CO. since 1900 has been just over 100,000,000 bbl. The production from the Peruvian fields will doubtless remain for some years at approximately the same level as during the past few years.

Jan 1, 1932

By C. Augustus Carlow

THE subject which has been allotted to me is so vast and far-reaching that it is impossible to deal adequately with it in the time available. A complete survey would occupy the spare time of any one man for many years, whereas the time available to me is measured in weeks In the circumstances, I have been fortunate in securing the aid of several willing collaborators, and shall endeavor to re present such information as presently exists in published form, examine the situation critically in the light of present-day conditions, and arrive at certain conclusions' which I shall venture to put forward for your consideration No one who has lived through the past 25 or 30 years, and who has witnessed the amazing achievements of recent scientific research, would venture to deny the possibility that new sources of energy-may yet become available, or to prophesy to what extent these may be harnessed to the service of mankind So far as we can see, however, coal, as a source not only of power and heat but also of that wonderful range of derivatives that form the raw materials of so many industrial processes, must continue to play a vital role in our economic life It is the chief mineral fuel, exceeding all other mineral resources in value, production and demand In value coal overshadows the industrial metals, while of the sources of energy-coal, oil, gas and water power-the first named is the most important Thus, for example, in the United States, coal as a fuel (that is, as a source of heat and power) is still predominant, the figures of percentage of

Jan 1, 1947

A. A. CENTER*—This paper reminds me of the beginning of the work of the Electrolytic Zinc Company of Australasia. Early work for this Company, as some of you may know, was done at the Bully Hill Plant in California. After working there for some time Herbert Gepp, now Sir Herbert, came to the Anaconda Co. plants in Montana where I met him. He spent some months there, in fact almost a year if I remember rightly. That was when we were breaking in the new electrolytic zinc plant at Great Falls, Montana. From there he went back to Australia and started in on the plant there. I believe they had an original plant of about 20 tons per day of cathode zinc. We heard from them for some time, until they were able to go along on their own, and they have done very well ever since as you have heard. Their practice, (the flow sheet, the leaching practice), has been quite different as reported in the paper and apparently they are still following that practice to some extent. While the earliest work on selective flotation was done down in Australia, the big companies there, strange to say, were far behind the American companies in taking it up; and it is only in comparatively recent years they have gone to the alkaline circuit and dropped out thereby more of their iron and lead. The zinc plant now is up to a capacity of 100,000 tons a year and I believe that may be notched up to about 105,000. T. H. WELDON*—I would like to ask

Jan 1, 1950