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By AIME AIME

IT its annual meeting on Oct. 21 and 22, the Engineers' Council for Professional Development announced the selection of J. P. H. Perry. vice-president of the Turner Construction Co. and prominent civil engineer of New York City as its new Chairman. He succeeds C. F. Scott, who becomes Chairman of its Committee on Professional Recognition. S. L. Tyler, Secretary of the American Institute of Chemical Engineers, succeeds A. B. Parsons as ECPD Secretary. R. E. Doherty is Vice-chairman. C. E. Davies remains as Assistant Secretary, as do R. L. Sackett as Chairman of the Committee on Student Selection and Guidance, O. W. Eshhach as Chairman of the Committee on Engineering Training, and Karl T. Compton as Chairman of the Committee on Engineering Schools.

Jan 1, 1938

By REED H. HYDE

IN these days of low metal prices and difficult marketing conditions, any treatment that will improve the grade of a product is of interest, particularly when the operation involves little or no addition to the total cost and may even result in a marketable by-product. Such a' combination of circumstances exists, in some cases, in the zinc industry, where it has been found that certain impurities can be removed from .the ore during the Dwight-Lloyd sintering operation, previous to reduction to metal. Consequently it is not surprising that zinc smelters having these sintering machines are paying particular attention to this phase of the operation. Loss of zinc as fume is very low under the conditions obtaining in sintering zinc ores, but impurities such as cadmium and lead are more readily fumed off and it is on this fact that the purification is based. As a result of preferential volatilization of these impurities a sintered product' is made from which purer zinc metal or oxide can be produced, while the fume may be collected and treated to recover the impurity metals. To be effective the operation must be carefully conducted, but no special equipment other than that of a well designed Dwight. Lloyd plant is needed.

Jan 1, 1931

By J. Marshall Downey

The most fortunately situated U. S. potash producer-whether in New Mexico, California, or Utah--once simply took from the ground a mixture of sodium chloride and potassium chloride, crushed it to a maximum of 10 mesh, and separated the two salts by physical methods. He piled the sodium chloride on the desert and sold the potassium chloride to fertilizer mixing companies. Seven companies in the Carlsbad basin of New Mexico now use at least three basic processes for making the separation and at least three more processes have been or are under investigation. In addition, two companies outside the basin use two methods for taking KC1 from natural brines

Jan 12, 1958

THE opening session* was held in the hall of the Franklin Institute, on Tuesday evening, June 20th, President Holley in the chair. The President introduced. Mr. Franklin B. Gowen, who addressed the Institute as follows MR. PRESIDENT AND GENTLEMEN : It has been made my pleasant duty to welcome you to the city of Philadelphia, but in so doing I shrink, with some natural reluctance, from appearing before an audience so much better fitted than I am to cope with the subjects which are usually presented to your association, and I can assure you that no trembling neophyte, first venturing within the groves of the Academy, or walking, with sacred reverence, in the gardens of Plato, felt more natural dread at the consequence of his own temerity than I do in appearing before an audience composed of gentlemen belonging to a scientific society of which I am but too sensible that until now I have been a member only in name. In olden times, upon entering a temple sacred to the worship of any deity, it was customary to lay some offering upon the altar, and, in following this custom, it will be my duty, before entering upon the more pleasant part of the task which is assigned me, to call your attention to a subject with which I have been somewhat familiar, and which is entirely within the scope of your investigations, in the belief that I may throw out some hints or some suggestions of a pro¬cess that may be fully developed by some of you, and eventually lead to the introduction of that which may be of service to the human race. The satirist who described the philosopher whom he met, as engaged in the process of extracting sunbeams from cucumbers, * A joint discussion of the subject of Technical Education, by the members of the American Society of Civil Engineers and the American Institute of Mining Engineers, was held in the hall of the Franklin Institute, on Monday evening, June 19th, and Tuesday morning, June 20th. This discussion has been printed in a separate pamphlet by both societies.

Jan 1, 1877

By AIME AIME

REGISTRATION and licensing of engineers is now being given consideration by a special committee of the Institute, authorized at the March meeting of the Board of Directors. The subject is one that has recently been or is now actively before engineering organizations in many of the States of the Union. In Washington, D. C., the Washington Society of Engineers and the local sections of ten national engineering societies, including the A.I.M.E., recently had a joint committee investigate the subject: this committee formulating a proposed law that has been presented to Washington engineers for their consideration. At the same time, the committee has summarized the reasons for and against registration of engineers in Washington, D. C. As many of these reasons are of more than local application, they are here reprinted so that all members of the A.I.M.E. may be informed on the subject. It is expected that some report of the Institute's Committee on Registration, State Councils and Professional Development will he made at some forthcoming meeting of the Board of Directors.

Jan 1, 1932

By R. B. Toombs

The national and international importance of Canada's minerals and metals producing industry is reported. The growth of the Canadian industry is traced from 1945, through the period of rapid development of the early 1950's, to the consolidation and expansion activities of the late 1950's and early 1960's. Mineral production in Canada during 1963-including steel, nonferrous metals, and fuels -is reported. It is estimated that by 1970 the Canadian industry will produce $3.9 billion worth of metals, nonmetals, and fuels.

Jan 8, 1964

By F. Weinberg

INTEREST is currently being directed toward grain boundary morphologies in zinc in terms of grain boundary facetingl and grain boundary energies.' Some years ago the present author attempted to measure grain boundary energies in 99.999 pct purity Zn as a function of boundary angle, using the standard procedure of measuring equilibrium angles of the boundary traces at triple points. This followed an investigation he carried out on preferential melting of |H (112) Fig. 1—Electron transmission micrograph of a stacking fault, grain boundary intersection in copper. GRAIN BOUNDARY STACKING FAULT Fig. 2—Schematic representation of the intersection of Fig. 1, indicating inclination angles 0 and trace angles $. specimens were prepared by the Bollman technique in an electrolyte of 70 pct methanol, 30 pct HNO3 main-tained at -30°C. The interfacial free energy of the high angle grain boundary and of the stacking fault is assumed to be thermodynamically equivalent to the corresponding in-terfacial tensions. In terms of the true dihedral angles & between the intersecting interfaces, the equilibrium of interfacial tensions in the direction parallel to the stacking fault yields: ysF = -ygb(cos F1+ cos ±cosF2) Here, ysF is the stacking fault free energy and ygb is the grain boundary free energy, assumed equal on both sides of the intersection. Forces acting normal to the grain boundary, of the form ??gb/?F,l are assumed negligible as the grain boundary remains straight for a considerable distance on either side of the intersection. The micrograph of Fig. 1 may actually consist of several closely spaced stacking faults on the same slip plane. The actual point of intersection between the grain boundary and the first stacking fault, and the equilibrium configuration of the intersection, should not be affected by the presence of the other faults, as

Jan 1, 1970

The volumes of Transactions, which are published annually, contain the list of officers, rules, etc , the Proceedings, and the papers revised for final publication (In this revision, after the prelimi¬nary publication, authors are permitted to use the largest liberty , and the changes and additions made in papers are sometimes important It should be borne in mind by those who study or quote a paper in the preliminary edition, that they may not have in that form the ultimate and deliberate expression of the author's views It should be added, however, that in the majority of cases there are no important changes) These volumes are for sale as follows, in paper covers

Jan 1, 1910

PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 ROBERY W HUNT 1883 JAMES C, BAYLES 1884-1885 ROBERT H RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B POTTER 1888 RICHARD PEARCE 1889 ADAM S HEWITT 1890 JOHN BIRKINBINE 1891-1892 H M HOWE 1893 JOHN FRITZ 1894 J D WEEKS 1895 E G SPILSBURY 1896

Jan 1, 1923

By Joseph W. Richards

(New York Meeting, February, 1912.) THE Ashio copper-mine of the Furukawa Mining Co. is situated 18 miles from Nikko, and 109 miles north of Tokyo, near the center of Japan. The mine-waters are run over scrap-iron, whereby most of the copper is precipitated as cement copper, leaving iron sulphate with some copper sulphate in solution. After using in the wet concentrating ore-dressing plant, the waste water contains clay and ore-slimes. The only avenue of disposal of this water is the Watarese river; but as this flows through valleys in which the water is used for irrigating the rice-crops, it is necessary to purify and clarify the water before discharge. The water amounts to from 600 to 700 cu. ft. (from 17 to 20 cu. m.) per minute, and averages about 0.00025 per cent. of copper, representing more than 18 tons of copper per month. The water carries H2SO4, FeSO4, Fe, (SO,),, CuSO4 and other metallic sulphates in solution, and clay, ore-fines, slimes and basic. iron sulphates as suspended matters. To purify and clarify the water, precipitation by milk of lime has been used, in three different ways, as follows: I. First Method, Copper not Recovered. Milk of lime was run into the water, and the mixture run through six settling-ponds, and then through a sand filter into the river. Fig. 1 is a view of the settling- and filtering-ponds. In the first pond, sand and metallic hydrates free from copper collected; in the next five ponds, slime, calcium sulphate, and metallic hydrates carrying copper settled out. The effluent carried from 0.1 to 0.05 mg. of copper per liter

Jun 1, 1912

By P. T. Carter, A. B. Murad, H. B. Bell

N. A. Gokcen (Michigan College of Mining and Technology, Houghton, Mich.)—The activities of silica, represented in Fig. 5 for the systems MnO-SiO2 and CaO-SiO2, are in disagreement with the established binary phase diagrams. At Ns102 = 0.50 in MnO-SiO2, and at Ns102, = 0.65 in CaO-SiO2, each binary system is saturated with respect to silica at 1550°C, and therefore as102, is unity in each case. The curves for as102 (FeO-SiO2) and as102, (MnO-SiO,) should nearly co-

Jan 1, 1953

By M. E. Gershon

A mixed-integer formulation of the mine scheduling problem is discussed and applied for the purpose of optimizing both the mine production sequencing and the mill blending and processing problem simultaneously. Previous attempts at solving these problem separately, although successful, fail to take into account the interrelationships between these problems. Project structure selves as the outline of this paper Generalized in its organization, this concept is useful for long, intermediate, and short range scheduling. Actual applications that show the concept also is applicable to mining a variety of ore are mentioned.

Jan 1, 1984

By B. F. Tillson

Mining may be defined as a general term for the working of valuable deposits of minerals, either organic or inorganic in origin, for their removal from the crust of the earth. Besides subsurface excavations, mining generically includes opencuts, clay pits and stone quarries, oil wells, sulphur wells, salt wells, placers, coal stripping, and the leaching of ore bodies. The origin of the word "mine" or "mining" is a matter of conjecture. A Celtic origin has been suggested since the Irish word mein, or the mwyn, meant ore, but it seems to have come from an olf French verb mineor, which meant to excavate, to make an underground passage as in the military appraoch to a fortification, sometimes called ?sapping.?

Jan 1, 1949

By S. A. Bradford

Internal-oxide precipitates in decarburized a iron alloys were studied by microscopic and X-ray methods. Diffusion of oxygen is primarily trans-granular, although large amounts of manganese or PhosPhorus cause preferred grain boundary dimsion at temperatures below 1450OF. Transgvanular internal oxidation follows the parabolic rate law with an apparent activation energy of 60 kcal per g-atom for decarburized rimmed steel and around 50 kcal per g-atom for higher alloy contents. The internal oxide is (Fe,Mn)0. Evidence was found for a miscibility gap in the FeO-MnO system. UNTIL very recently, the internal oxidation of metals was studied primarily as a scientific curiosity or, in a few cases, as a means of strengthening alloys by precipitation hardening. However, with the recent development of low-carbon enameling sheet steel, internal oxidation has become a problem of practical importance to the steel industry. For example, in 1961 it was reported1 that internal oxidation of steel can occur during decar-burization by open-coil annealing and will reduce the notch ductility of the sheet unless the process is carefully controlled. The present study was therefore undertaken to learn more about the rates and mechanism of oxygen diffusion and oxide formation in iron alloys. BACKGROUND The process of internal oxidation has been well-defined in the literature:',' oxygen dissolves in an alloy, diffuses inward from the surface of the metal, and reacts to form a precipitate with the alloying element that will provide the most stable oxide. he growth of the finely divided so-called subscale, i.e., the internal-oxidation zone, depends on the diffusion rates of both the oxygen and the reactive element.4 Investigators have generally found that increasing the temperature increases the size of the oxide particles, the rate of subscale growth, and the tendency to transgranular diffusion. With very few exceptions, the square of the thickness of the internal oxide layer is directly proportional to the reaction time. Given two conditions easily satisfied for iron systems— a) an oxygen solubility much less than the concentration of the alloying metal and b) an oxygen-diffusion rate to the oxide boundary much faster than that of the alloying element—then the general expression developed by Rhines and co-workers5 for the parabolic growth rate of the internal-oxide zone can be simplified to the following form: where Co and CM are, respectively, the solubility of oxygen and the concentration of the alloying element, DO is the diffusion coefficient of oxygen, O/M is the weight ratio of oxygen to metal in the precipitated oxide, and x is the thickness of the internal-oxide zone after an annealing time t. Both the oxygen solubility and diffusion coefficient can be approximately expressed as functions of temperature by Arrhenius-type equations: in which H and Q are, respectively, the heat of solution and the activation energy of diffusion. Consequently, the apparent activation energies calculated from Arrhenius plots are the sum of the heat of solution of oxygen in iron and the activation energy for diffusion of oxygen. The data, if not the interpretation, of Schenck et al.8 bear out the fact that oxygen diffuses in the atomic form. The general rate law for atomic diffusion is: the reaction rate being proportional to the square root of the pressure at low pressures. Benard and Moreau8 studied both the surface oxidation of Fe-Ni alloys and the gradual penetration of oxygen into the metal. They observed that oxide particles first form along grain boundaries and then grow to form continuous films that eventually envelop the grains. The parabolic rate law does not usually apply in these cases, especially at the higher temperatures. The oxide formed is wustite which gradually transforms into Fe3O4 and finally into Kennedy and coauthors8 examined Fe-Ni alloys with 26, 75, and 84 pct Ni oxidized at 800°C and

Jan 1, 1964

ALABAMA Anniston.-Carrington, F. G. Auburn.-Brown, R. L. Bessemer.-Abbott, C. E. Dobbs, G. G. Ferguson, V. Salmon, H. S. Schaber, C. F. Birmingham.-Aldrich, T. H. Aldrich, T. H., Jr. Allen, A. W, Ball, E. M. Bonnyman, J. Bowron, J. Bush, M. W. Crawford G. G. Crockard, F. H. Ellis, E. E. Fairbairn, C. T. Gallacher, J. Geisiner, H. S.

Jan 1, 1917

J. L. CHRISTIE, Chairman T. S. FULLER, Past-chairman W. M. PEIRCE, Vice-chairman W. A. SCHEUCH, Vice-chairman E. M. WISE, Secretary International Nickel Co., Bayonne, N. J. W. M. CORSE, Treasurer Executive Committee H. A. BEDWORTH G. O. HIERS D. K. CRAMPTON R. H. LEACH E. H. DIX, JR. R. F. MEHL J. A. GANN J. WALTER SCOTT' JEROME STRAUSS Finance Committee T. S. FULLER, Chairman W. M. CORSE H. S. RAWDON C. H. MATHEWSON SAM TOUR

Jan 1, 1934

By F. Louis Grammer

THE difference between blast-furnace gas and ordinary producer-gas is chiefly that blast-furnace gas is richer in CO, and poorer in hydrocarbons and hydrogen, as is shown in Table I. TABLE I.-Volume-Composition of Producer-Gas and Blast-Furnace Gas.. Producer-Gas. Blast-Furnace Gas. Per Cent. Per Cent. (Volume.) (Volume.) CO . 22 to 33 25.5 00., . 6 to 3 13.0 H . . 13 to 7 1.5 CH, 3 to 1.5 0.0 N . 54 to 60 60.0 If natural gas, water-gas, or by-product coke-oven gas be available, blast-furnace gas can be made to resemble very closely in calorific value the average producer-gas by merely mixing in one of these products, which are richer in hydro-carbons and, hydrogen. Blast-furnace gas, however, possesses a virtue which is sometimes absent in producer-gas, especially with coals very high in sulphur-namely, that blast-furnace gas is relatively free from sulphur. In some regions the sulphur in coal is an acute problem, and it is highly desirable to find uses for the products which are specially high in sulphur-content. An advantage would be gained if coal was coked before charging into the gas-producers, but this adds to the expense. Sulphur may be partly eliminated from coal by washing it, the success depending upon the form in which the sulphur occurs, and upon the efficiency of the washer, but it cannot always be removed to the extent desired at most American plants. It is not practicable to remove all the sulphur from producer-gas by washing it, though Mr. Reinhardt, of Germany,

Sep 1, 1908

By John H. Hearding

Induction heating, together with automatically controlled tempering and hardening is giving Oliver faster and more accurate bit sharpening, while experiments with bit taper promise to offer increased footage per bit.

Jan 10, 1953

By H. N. Treaftis, J. W. Cahn

THE previous determinations of the solvus of tin in solid lead disagree with one another by as much as 40°C or almost 10 at. pct. Even determinations that appear to be careful differ considerably in both the solubility and its temperature coefficient. Recent kinetic workl -3 on the rate of precipitation of tin from lead-tin alloys and thermodynamic work4 on the heat of solution of tin in lead have given some insight into the time necessary to reach equilibrium in this system. As this time is longer than that used in almost all previous determinations of the solvus, these determinations are questionable. Since the interpretation of recent kinetic results requires accurate values of the equilibrium solubility the present work was undertaken. DISCUSSION OF PREVIOUS RESULTS The methods used in previous studies may be placed into three classes: 1) Several alloys covering a range of compositions are allowed to reach "equilibrium" at a certain temperature.5-7 Some property, such as the X-ray lattice parameter of the lead-rich phase or the re- sistivity of the alloy, is then measured as a function of composition. The solubility limit for that temperature is taken to be that composition at which a discontinuity in the property occurs. However, the recent kinetic work has shown that tin precipitates in two stages. The first stage is rapid but leaves the lead still supersaturated. The second stage is very slow, and it seems from the equilibration times quoted by the investigators of the solvus that the end of the first stage of precipitation was usually mistaken for equilibrium. This is especially true at temperatures below 100°C where the first reaction is still quite rapid (from minutes to months), but where the second stage is so slow that very long holding times are required to reach equilibrium. Alternatively micrographic work8 on several alloys of different compositions seems to have given good results if done carefully. 2) The beginning of precipitation in a homogenized alloy is measured as it cools slowly8-10. Since reactions in solids undercool easily, such determinations will always give too low a temperature for the solvus. 3) Some property of an alloy is measured as a function of temperature while the alloy is above the solvus.5,9,11 The range of temperature can usually be extended slightly into the two phase region. Then the alloy is precipitated at a much lower temperature and slowly reheated. The solvus is taken to be the lowest temperature where the property of the reheated alloy is equal to that previously determined for the homogeneous alloy. Usually one also expects a discontinuity at the solvus in the temperature variation of the property for the reheated alloy. The difficulty in this method is the sluggishness of the dissolution process, and this method may give too high a solvus temperature. EXPERIMENTAL The phase boundary or solvus temperature was determined by a modification of method 3 for a series of chemically analyzed high-purity alloys, ranging from 5.1 to 26.4 at. pct Sn. The resistance, as a function of temperature, of a sample of homogenized alloy (which could easily be undercooled) was compared with the equilibrium resistance which that alloy sample attained after precipitation at room temperature followed by long isothermal anneals at various temperatures. Before each anneal the sample was rehomogenized and reprecipitated. The solvus temperature could be located to within 1°C as the intersection of the resistance vs temperature curves for the homogenized and equilibrium alloys. No attempt was made to locate the phase boundary more accurately since the limiting factor was the precision with which the alloys could be analyzed. This precision was ±0.1 wt pct Sn and corresponds to an error of 1 deg in temperature. This use of isothermal anneals differs from some of the previous investigations in which method 3 was used with baths of slowly rising temperatures. It was found early in the investigation that solvus temperatures tended to be high if the latter method was used even at extremely slow heating rates. For example a

Jan 1, 1961

By Will Clark

HE who enters a mining claim within an Indian reservation of the United States of America acquires no rights thereby, because of the fact that the lands within such Indian reservation are not a part of the public domain, and cannot be located or acquired as mineral land. However, where such an entry is authorized as to a particular reservation by an Act of Congress, such claims as may be entered under such authorization are thereby segregated from the reservation, and the Indian title is extinguished. Under the Choctaw Constitution, any citizen of that nation, in other words any Choctaw Indian, who discovered a coal mine, acquired an exclusive right to all coal within a radius of 1 mile. The laws of the Chickasaw nation provided for the formation of corporations to develop coal and other mines, with authority to contract with others to develop and work the mines. Under these laws, leases were made; but Congress subsequently abrogated all existing leases, prohibited all persons from receiving royalties from such mines, and provided that all coal within the nation should remain the common property of the tribes. Such leases are now expressly prohibited by an Act of Congress (32 United States Statutes at Large, 655). All leases of mineral lands upon Indian reservations must now be made under regulations promulgated by the Secretary of the Interior, and the royalties must be paid into the United States Treasury for the benefit of the tribes. In Canada the Indians have no rights to the royal mines and minerals, and the government can make no stipulation with the Indians which would affect the rights of the Province in which the lands are situated. Therefore, while it is true that under our present law no rights can be acquired to a mining claim within an Indian reservation, it seems to be fully within the authority of Congress to make laws, giving such rights to mineral locators as it may deem necessary or expedient.

Jan 6, 1914