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By L. D. Jaffe

IN previous metallographic work on titanium and its alloys, difficulty has been encountered in distinguishing spheroidal particles of titanium hydride, dispersed in a-titanium, from other phases that may be present, such as p-titanium. This problem is common in examination of commercial unalloyed titanium.' In the course of an investigation of the Ti-H phase diagram, it was noted that titanium hydride, dispersed in a matrix of a-titanium, showed strong optical anisotropy when examined under polarized light. With sensitive tint illumination, particles of the hydride, when the stage is rotated, changed from bright yellow to bright blue in color. Since P-titanium is cubic, it showed no color change on rotation, remaining dark gray or blue-gray. Although a-titanium is hexagonal, it showed only a minor color change, going from pale pinkish-blue to pale purplish-blue. These colors could be modified somewhat by adjustment of the illumination. They were observed in specimens mechanically polished, both without etching and after etching with hydrofluoric acid-nitric acid mixtures in either water or glycerine. The strong color change of the hydride seems to offer a simple method for its metallographic identification. Optical anisotropy of titanium hydride is inconsistent with its accepted face-centered-cubic structure.' Samples of iodide titanium containing 6 to 40 atomic pct deuterium were prepared for diffraction studies. After deuterating and slow cooling' the samples were held 21 % hr at 400 °C, water quenched, held 61 hr at 100°C and quenched, then held 64% hr at 255 C and quenched. Debye ex-posures with MoKa X-rays and 1.111A neutrons were made at room temperature of samples as-deuterated and after the 100" and 255°C treatments. Table I shows the lines observed, in addition to those attributable to a-titanium. These data show that the hydride phase was not cubic, but probably tetragonal. The titanium atoms appeared to form a body-centered-tetragonal lattice complex, two titanium atoms per cell, with approximate dimensions: a = 3.12A, c = 4.18A, and c/a =1.34A. This is equivalent to a face-centered-tetragonal complex, four titanium atoms per cell, with approximate dimensions: a = 4.42A, c = 4.18A, and c/a - 0.946A. The presence of the 2.98 and 1.81A neutron lines indicates that the true Bravais lattice is not identical with this lattice complex, but may be primitive tetragonal with dimensions some multiple of those of the complex. The relative intensities of the hydride and a-titanium X-ray lines as functions of overall composition indicated that the hydride, presumably in equilibrium with the a at 100" to 255"C, contained more than 62 atomic pct H. Acknowledgments The experimental work covered in this report was done at Brookhaven National Laboratory, through the courtesy of D. Gurinsky. The cooperation of J. Sadofsky, 0. Kammerer, A. McReynolds, and A. Cendrowski is gratefully acknowledged.

Jan 1, 1957

By G. R. Belton, Y. K. Rao

A galvanic cell, using liquid MgCl2 or MgC12-CaC12 mixtures as the electrolyte, has been used to determine activities in Mg-A1 liquid alloys between 700' and 880°C. The incovporation of a chlorine electrode in the cell also allowed measurements to be made of the standard free energy of formation of MgCl2(l). The results are shown to be in good agreement with thermo-chetrlical values from the literature, and this is taken as evidence that the small, known solubility of magnesium in iMgCl2 introduces no significant error in galcanic cell measurements. Within experimental error, the activity coefficients and relative partial molar enthalpies at 800°C are shown to be represented by the following "subregular" solution equations: logy~~ =-0.68(1 -xMgj3 log yAL =-1.02(1 - XMf + 0.68(1 - XMf H.M = -4400(1 - %)3 / cal Mg 7Ag' HZ =-6600(1 - xA1)' + 4400(1 - XMf cal SCHNEIDER and toll' have used a transpiration technique to measure the vapor pressures of magnesium over Mg-A1 alloys between 544" and 594°C. amsstad,' however, has since suggested that the extrapolation to zero flow rate, used by these authors in interpreting their apparent pressure vs flow rate data, gives unreliable results. Rogers, Tomlinson, and Richardson,3 in interpreting the results of solution equilibria between Mg-A1 alloys and liquid MgC12, also considered the measurements of Schneider and Stoll to be unreliable and preferred to derive activities for the alloys from the earlier boiling point determinations of ~eit~ebel~ and the partial molar heats recommended by Kubaschewski and ~atterall.~ These latter heats were based substantially on the early calorimetric work of Kawa-kami but, unfortunately, his work on other systems has sometimes been found to be inaccurate.7 Rogers et al., in the above-mentioned paper,3 tentatively concluded that the most likely species responsible for the limited solubility (0.3 mole pct at 800°C) of magnesium in MgC12 were Mg° (neutral) and Mg2++. Two more recent studies8,9 have supported Mg2++ as the soluble species. In the present study, activities in Mg-A1 alloys have been determined by means of a galvanic cell involving liquid MgCl2 or MgC12CaCl, mixtures as the electrolyte. Since the reactive nature of magnesium precluded simple Faraday yield experiments, a chlorine electrode was incorporated in the cell in order that the performance of the cell could be checked by measurements of the heat and free energy of formation of MgC12. This procedure was considered necessary since it has been suggested1' that the solubility of a metal in a molten salt might introduce electronic conductivity; also, previous determinations of the standard electrode potential for MgC12 differed by as much as 70 mv11-13 EXPERIMENTAL Materials. Analyses of the materials used in preparing the alloys and the electrolyte mixtures are presented in Table I. The alloys were prepared by induction melting weighed amounts of the metals in a graphite crucible held under an argon atmosphere. Pure anhydrous magnesium chloride was prepared by heating the mixture MgCl, . 6H20 +NH4C1(1:1) to 650°C, followed by melting under dry argon. The melting point of the dry MgC12 was found by differential thermal analysis to be 714.8oC, which compares well with the accepted value of 714C.14 This agreement was taken to be an indication of the high purity of the dried salt. Table I. Compositions of Materials, wt pn Impurity Mg Al MgCI2 CaCI, Ba - - 0.005 Ca - - 0.010 Cu 0.02 0.02 Fe - 0.10 0.001 0.010 Pb 0.01 - 0.001 0.005 Mn 0.15 0.001 Si - 0.10 Sr - - 0.005 MBSO* - 0.040 ARGON TUNGSTEN CHLORINE LEAD—411 11 II ALUMINA 'A I / ave GRAPHITE on irA~_ ( ^"l ROD MAGNESIUM S>ILICA~^ /, OR ALLOY-. I /A] ___________ -«^- _ ELECTROLYTE I y FRITTED DISCS Fig. l—Arrangement of chlorine and metal electrodes in electrolytic cell.

Jan 1, 1970

The following is an incomplete list of members and guests who called at Institute headquarters during the period Sept. 10, 1919, to Oct. 10, 1919. L. D. Anderson, Salt Lake City, Utah. P. S. Matthews, Newark, N. J. Ray J. Barber, New York City. A. Poole Maynard, Atlanta, Georgia. L. A. Barton, Major U. S. Engineers. L. J. Mayreis, Jamshedpur, India. J. A. Battle, Chicago, 111. Benj. L. Miller, Bethlehem, Pa. R. W. Bissell, New York City. Geo. D. Morgan, Bartlesville, Okla. Gilman E. Brown, Shanghai, China. A. C. Munroe, El Paso, Texas. Stanley Brown, Chuquicamata, Chile, Paul I. Norton, Jr., Columbus, Ohio. S. A. Walter G. Perkins, Stanford University, Norman Carmichael, Clifton, Arizona. Cal. Richard H. Catlett, Newark, N. J. Fred S. Porter, Seattle, Wash. Roderic Crandall Charles E. Prior, Cherry Creek, Nevada John J. Croston, Atlanta, Georgia. G. M. Richards I. N. Dally, Seattle, Wash. Gilbert Rigg, Melbourne, Australia. A. Faison Dixon, New York City. Pierre H. Sauvajol, Paris, France. Walter Dobbins, Springfield, Ill. Carl Scholz, Chicago, Ill. Foss E. Douglass, Rancagua, Chile. Ellsworth H. Shriver, Marysville, Ohio. H. S. Emlaw, Grand Haven, Mich. Harvey B. Small, Magangue, Colombia. R. S. Everet, Barre, Mass. Henry B. Smith, New Britain, Coma. H. W. Gipp, Melbourne, Australia. J. T. Smoody, Cornwall, Pa. F. A. Glass, Brainerd, Minn. S.. J. Speak, London, England. C. D. Grier, New York City. D. R. Thomas, New York City. James L. Head, Rancagua, Chile. Kirby Thomas, New York City. Geo. B. Holderer, New York City. R. M. F. Townsend, Washington, D. C. W. Spencer Hutchinson, Boston, Mass. Carl J. Trauerman, Helena, Mont. Henry Jequier, Paris, France. A. C. Veatch, London, Eng. L. W. Kemp, Chuquicamata, Chile. Myron R. Walker, Pittsburg, Pa. Herbert S. Kohlberg, El Paso, Texas. Curtis C. Webb, New York City. H. M. LaFollette, La Follette, Tenn. James Wilding, San Francisco, Cal. Richard Lamb, New York City. S. H. Zimmerman, New York City.

Jan 11, 1919

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) The following members registered at Institute headquarters during the month of April: J. C. Ralston, Spokane, Wash. E. P. Ross, Johnson City, Tenn. C. H. James, London, Eng. F. L. Garrison, Philadelphia, Pa. E. H. Benjamin, Oakland, Cal. A. Radcliffe, Copiapo, Chile. W. H. Shockley, Palo Alto, Cal. S. S. Wyer, Columbus, Ohio. A. C. Mauney, Salisbury, N. C. W. B. Kunhardt, Reading, Pa. A. W. Newberry, Los Angeles, Cal. W. E. Saunders, Philadelphia, Pa.

Jan 5, 1913

By J. D. Vincent, Pierre R. Hines

INTRODUCTION OF FROTH FLOTATION INTO THE UNITED STATES "The introduction and development of the flotation process have proved to be of such momentous importance to the mining industry of the United States that they deserve to be considered historically ." T. A. Rickard l James M. Hyde installed the first froth flotation process in the U. S., about Aug. 1, 1911, at the Basin Reduction Co. plant, Basin, Mont., which was then under lease to the Butte and Superior Copper Co.2 Two months later, the Minerals Separation Ltd.. filed suit in the U. S. District Court of Montana against Mr. Hyde char& him with infringement of their Patent 835, 120/1906. The U. S. District Court decided in favor of Minerals Separation Ltd. on July 28, 1913. This decision was reversed by the Ninth Court of Appeals in San Francisco on May 4, 1914. Then the U. S. Supreme Court, on Dec. 11, 1916, upheld the patent on three counts only but restricted it to 'the use of less than one percent of oil.” The Miami Copper Co. was sued by Minerals Separation on Oct. 10, 1914, for infringement of Patents 835,120 and 962,678, and 1,099,699. The Miami Copper Co. was operating under John M. Callow's froth flotation process Patent 1,104,755/~uly 23, 1914. Miami lost this suit in the District Court of Wilmington, Del., and appealed to the Court of Appeals, Third Circuit, Philadelphia. The Third Court of Appeals decided against Miami, May 24, 1917. The case was referred to a Master and hearings to determine profit and damages were not settled until 1923. Nevada Consolidated Copper Co. was sued Sept. 9, 1919, and Magma Copper Co. was sued Jan. 10, 1920. Thus, the first ten years of froth flotation in the U. S. were beset by patent litigation. This litigation suppressed the free circulation of new discoveries or useful information that might be cited in a patent suit against the originator; it accounts for many of the blank spaces in the historical record. T. A. Rickard3 has reviewed the history of flotation and has given the chain of discoveries, patents, and processes that resulted in froth flotation. He has re- ported also on the patent litigation beginning in 1911 and ending in November 1923, when Minerals Separation's Patent 835,120 expired. He comments on

Jan 1, 1962

By R. A. Wolfe, H. W. Paxton

Self-diffilsion coefficients for cr51 and Fe55 in 12 pct Cr-Fe and 17 pct Cr-Fe for Fe55 in chromium, and for Cr51 in vanadium have been measured. The results are compared with other values for the Fe-Cr system, and with the various theories of diffusion in hcc metals. Some empirical correlations are discussed between Do and Q in hcc systems, or, expressed differently, the constancy of ?G*/T solidus for seveval bcc metals and alloys is noted. It appears very probable that a vacancy mechanism is operative in bcc metals, hut this cannot he stated with certainty. THE great bulk of work on diffusion in metals, both experimental and theoretical, was for many years concentrated on those with close-packed and, in particular, fcc lattices.1,2 There appears to be little doubt that the mechanism of diffusion in these solids is vacancy migration, leading to mass transfer and in substitutional solid solutions to a Kirken-dall effect.3,4 For bcc metals, the picture is much less clear. The Kirkendall effect certainly occurs in several alloys.5-10 However, attempts to understand the factors contributing to the pre-exponential in the usual expression for the diffusion coefficient D =D, exp {-Q/RT) by extension of ideas useful in close-packed lattices have not always been successful. Zener,11 Leclaire,12 and Pound, Paxton, and Bitlerl3 have suggested that various forms of ring diffusion may be important in some bcc metals. For close-packed metals, Do is usually about 1 sq cm per sec and Q - 35Tm kcal per mole (Tm = melting temperature in OK). The theory of Pound et al. suggests for ring diffusion that Do may be about 10-4 and Q, although difficult to calculate with any precision, would be significantly less than 35 T,. The experimental results on self and solute diffusion in ? uranium14,15 and ß zirconium,10 and for solutes in 0 titanium,17 and possibly for self-diffu- sion in chromium below about 0.75 T,," gave some credence to this theory. However, not all bcc materials display low values of DO and Q, and the exceptions were not predicted by any theory. Furthermore, it has recently become apparent that, in bcc materials, log D is not always linear with T-l if a sufficiently wide range of temperature is studied.16,18 This variation may be such that Q may increase18,19 or decrease20 with increasing temperature. The present work was undertaken in an attempt to provide further diffusion data on bcc metals, and to try to understand the factors which contribute to differences in behavior between the various elements. For part of this work, the Fe-Cr system was chosen since it is of considerable technological importance, and data on 12 pct Cr and 17 pct Cr alloys appeared well worthwhile to supplement that existing for the remainder of the stern.18,22 The diffusion of Fe55 in chromium was studied as an example of a more or less "normal" tracer element in a possibly abnormal host lattice. Finally, no data were available for vanadium, the neighbor of chromium in the periodic table, because of lack of a suitable isotope so cr55 was used as a tracer in a few preliminary experiments. For convenience, we shall refer to elements whose Do and Q are low compared to those predicted by Zener's theory as "anomalous". PROCEDURE This investigation determined self-diffusion rates by means of radioactive tracers and the integral-activity method first utilized by Gruzin.23 In this method a thin layer of radioisotope of the diffusing element is plated or coated onto a planar surface of the diffusion sample, which is then given an isothermal-diffusion annealing treatment. The determination of an activity-penetration curve involves measuring the residual activity of the specimen after each successive layer or section has been removed parallel to the original planar surface. The method used here is essentially the same as that used by Gondolf18 and Kunitake.21 Two radioactive tracers, cr51 and Fe55, were used in this investigation. Diffusion coefficients were determined for the diffusion of one or both of these tracers in four different materials, viz., Fe-12 wt pct Cr alloy, Fe-17 wt pct Cr alloy, chromium, and vanadium. The diffusion samples had nominal dimensions of 1.5 cm diameter and 0.5 cm thickness. The grain size was several millimeters for the Fe-Cr alloys and at least 1 mm for the chromium and vanadium samples. Accurately planar surfaces

Jan 1, 1964

By Benjamin Smith Lyman

The question of the original extent of the anthracite-beds of Pennsylvania has often been raised; and even discussed with reference to the probability of their present existence under the New Red, a matter of immense practical importance. So high an authority as my revered master, J. P. Lesley, Honorary

Jan 1, 1903

September 28, 1915. The Nominating Committee of the American Institute of Mining Engineers has the honor to present the following nominations for officers of the Institute to be voted for at the 1915 Annual Meeting: For President: L. D. Ricketts District 0 For Vice-Presidents: Karl Eilers District 0 James MacNaughton District 4 For Directors: Thomas B. Stearns District 7 Charles F. Rand District 0 Charles W. Goodale District 5 Edwin Ludlow District 2 George D. Barron District 0 F. W. BRADLEY, Chairman.

Jan 11, 1915

ROBERT H. LEACH, Chairman ROBERT F. MEHL, Past-Chairman D. K. CRAMPTON, Vice-Chairman E. M. WISE. Vice-Chairman W. M. CORSE, Treasurer LOUIS JORDAN, Secretary 29 West' 39th St., New York, N. Y. Executive Committee 1940 1941 ARTHUR PHILLIPS W. P. SYKES L. E. SCHUMACHER E. A. ANDERSON CARL E. SWARTZ D. L. COLWELL 1942

Jan 1, 1939

By Charles Bohdanowicz

Production of crude in 1937 decreased (Tables 1 and 5) by about 2 per cent, while gas production for that period increased by about 6 per cent after a slight decrease in 1936 (0.4 per cent).' As in preceding years, drilling operations were confined principally to extensions of old oil fields in the Jaslo district (fields 1 and 7) and to some extent to such extensions in the Stanislawbw district (field 27). Deepening of old wells to horizons reached more recently by new wells gave on the average better results per well than those attained by new wells (Table 3). Reserves of proved lands have increased some by new oil fields discovered, Targowiska (field 8) and Czarna (field 19) both of which, however, have only small production. The Daszawa gas field (field 25) has not been extended, but two new gas fields were located instead— Opary, distant 25 km. (151/2 miles) northwest of Daszawa, Balicze at 12 km. (7 1/4 miles) southeast of Daszawa, and Kalusz (TESP Company exploiting potassium salts) in the vicinity of the town of that name (field 33). Drilling upon the gas area near Tarnbw and Debica, while gas-bearing sandstone had been found at depths of from 300 to 512 meters (984 to 1680 ft.) (Zdziary No. 2) and at 220 m. (722 ft.) [pressure 11 atmospheres, flow 24 cu. m. per min. (847 cu. ft.)] (Przyborbw No. l), has not as yet ascertained horizons qualified for permanent exploitation. The exploring well near Kos6w remained for the last seven months at the depth of 1420 m. because of the collapse of rotary drilling pipe. Below the 300-m. level no gas sands have been encountered at this well. Gas Reserves In connection with the broad plan of developing industrially the sector of Poland lying between the Vistula and the San Rivers, and extending farther north as far as the city of Radom, there arose the necessity of a more accurate calculation of gas reserves for the fields of

Jan 1, 1938

By N. A. Gokcen

THE data of Chaudron,1 Tonosaki,2 and Collins³ on the thermodynamic properties of MOO, disagree widely. These authors, by using essentially similar methods, studied the following reaction: 1/2MoO2(s) + H2(g) == i/2Mo(s) + Ph,o H2O(g),K = —----- [1] Ph2 Tonosaki used a vacuum system consisting of a furnace containing MOO, and a water saturator whose temperature was kept at 25 °C with a thermostat. After repeated evacuation, hydrogen was admitted slowly into the system. The experiments were based upon the fact that at a constant furnace temperature and constant partial pressure of water, the total pressure of gas mixture over MOO? + Mo is constant. Any attempt to vary the pressure by external forces would vary only the amounts of MoO2, and Mo, after which the pressure should return to the equilibrium value in accordance with the equilibrium constant of reaction 1. The actual value of K was determined from the total equilibrium pressure (sum of Ph2o + Ph2) at each temperature. The total pressure of gas was varied within the range of 80.2 to 125.4 mm Hg, within a temperature range of 645" to 823 °C. The results were summarized as log K = 0.9413 — 1444.6/T for reaction 1. The ratio of H2O/H2 was considered to be uniform in spite of the presence of a thermal gradient across the static gas phase. It was shown by Rosenqvist and Cox,' however, that in somewhat similar circumstances the error resulting from thermal diffusion may be large. Collins³ improved Tonosaki's method by attempting to avoid thermal diffusion errors. His equilibrium data were obtained at 700°, 800°, and 900° C, and the result for reaction 1 was expressed as log K = 1.258 — 1822/T. The purpose of this investigation was to study reaction 1, avoiding the thermal diffusion errors, and to obtain equilibrium data in a considerably wide temperature range for the reliable extrapolation of the resulting thermodynamic functions. Experimental Procedure The diagram of the apparatus is shown in Fig. 1. Tank hydrogen was passed through a tube containing platinized asbestos at 425 °C in order to convert a trace of oxygen into water vapor. The flow rate was carefully controlled with a capillary-type flow-meter B and a bubbling column D. The gas was then presaturated sufficiently at P and led into a condenser system immersed in a thermostat, controlled to within ±0.002C. The temperature of the thermostat was measured with a thermometer calibrated against a certified standard. The temperature of P was adjusted to avoid the condensation of unduly large amounts of water as judged from the rate of flow out of the capillary tube M. Argon was purified by passing it through magnesium chips kept at 630°C. After passing through the flowmeter B', it was mixed with moist hydrogen emerging from the thermostat. The resulting gas mixture was then led into the hot zone of the furnace through the heated glass tubing and the silica tube S, thus insuring the same ratio of PII2o/Ph2 from the condenser to the reaction chamber, thus avoiding thermal diffusion. The entire gas system was of all-glass construction, except at the magnesium train. The furnace comprised a glazed alumina tube over which a 15-in. platinum coil was wound. The lower end of the alumina tube was tightly closed with a brass bottom and a silicone rubber gasket, and the upper end with two glass disks, each with a hole of 1/16 in. in diameter, through which the gas mixture escaped into the atmosphere. A back-up coil of kanthal wire facilitated the temperature control of the furnace. A coil of annealed molybdenum strip of 99.99 pct purity, 0.005 in. thick and 0.050 in. wide, and weighing 17 g was hung in the furnace with a 0.010-in. platinum wire attached to one end of a sensitive analytical balance. The temperature of the furnace was measured with a Pt-Pt-10 pct Rh thermocouple checked against a standard. The experimental procedure consisted of heating the gas purification trains, adjusting the gas flow rates, attaining a constant thermostatic temperature, flushing the entire system for 2 hr while heating the furnace to well above the expected equilibrium temperature and then cooling it at a rate of 0.3°C per min during which time the change in the weight of molybdenum was observed on the balance. For a given thermostatic temperature, i.e., a constant Prr,o/Px,, molybdenum oxidized upon cooling slightly below the equilibrium temperature. The procedure was then repeated by heating the furnace and thus reaching a temperature slightly above the equilibrium value. The average of the two temperatures, differing by 2" to 3"C, was considered to be the true equilibrium temperature. In order to determine the stoichiometric composition of the oxide phase present in this investigation,

Jan 1, 1954

CONTENTS PAGE Ross, J. M. and WAYLAND, R. G.-Mining Methods at the Homestake. Discussed by Benjamin F. Tillson, R. M. Raymond, I, H. Barkdoll, Arthur Notman 1 EMMEL, RUDOLPH.-Mining Methods in Zaruma District, Ecuador. Discussed by Rudolph Emmel, George A. Packard, Fred Hellmann, R. M. Raymond, Arthur Notman 2 MISHLER, R. T. and BUDROW, L. R.-Methods of Mining and Ore Estimation at Lucky Tiger Mine. Discussed by Fred Hellmann, Benjamin F. Tillson...4 PARK, JOHN FURNESS.-Mining Methods of Jarbidge District. . Discussed by R. S. Lewis : 5 Mining Methods at the Homestake Discussion of the paper of A. J. M. Ross and R. G. WAYLAND, presented at the New York Meeting, February, 1925, and issued, as Paper No. 1408-A, with MINING AND METALLURGY, February, 1925. BENJAMIN F. TILLSON, * Franklin, N. J.--It requires a good deal of timber to operate, especially the caving systems. An important function in mine operations now seems to be forestry and to operate a timber tract in order to insure a supply of timber. By depleting the timber resources of your section, you only increase your costs later when timber must be brought in from the Pacific Coast or the East. Our experience has been that any square-set method of timbering is the most expensive. Timbering for stoping systems, top slicing if you will, although it uses a large volume of time does not require as expensive timbering as the square-set method; also it does not require as long a life for-the timber, so that such wood as birch and maple, which have strength but not long life under the fungus conditions in the mine, may be used. All the drifts in the orebody are thoroughly timbered, and it has required a lot of timber. If we had it to do over, we would spend a lot more money in the development of rock drifts; as a matter of fact, we must ultimately come to that any way.

Jan 6, 1925

Abbott, Franklin E. Adgate, Frank Aertsen, G. Aid, Kenneth Albert, H. I. Alexander, D. B. W. Allan, Wm. G. Allen, R. 0. Allen, Roy H. Aller, Mr. and Mrs. F. D. Altmayer, Maurice Ambler, Harry A. Ambrose, A. WV. Ammon, Mark A. Ammon, Mr. and Mrs. Robt. Anderson, George H. Anderson, Mr. and Mrs. L. D. Andros, S. 0. Appleby, W. R. Archer, R. S. Armitage, Paul Arobb, Alden D. Arthur, Walter Ashman, A. 0. Atkinson, R. H. Aupperle, J. A. Austin, D. F. Avery, G. E.

Jan 11, 1919

Jan 1, 1969

The Library of the above-named Societies is open from 9 A.M. to 9 P.M. on all week-days, except holidays, from September 1 to June 30, and from 9 A.M. to 6 P.M.. during July and August. The Library contains about 55,000 volumes, including sets of technical periodicals and the publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library can render valuable service through correspondence; letters requesting information-will receive special attention. The Library is prepared to furnish references and copies of articles on mining and metallurgical subjects; to determine the existence of mining-maps, and to furnish general information as to the geology and mineral resources of all countries: All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. The members of the Institute. can be of service to the Library by forwarding copies of mining-reports, maps privately issued, and similar material, which will he classified, indexed, and made available to other members. Suggestions for additions to the Library, either by purchase or personal solicitation as gifts, will be welcomed. It is hoped that members while in the city will use the Library freely, and assurance is given that most careful service will be rendered to them.

Jan 5, 1913

Map

Jan 1, 1941

Aamot, Olav Crone, (M'29) Chem. Engr., Elektrokemisk, Raadhusgt. 23, Oslo, Norway. Abadilla, Quirico A., (M'3S) Min. Engr., Dir., Bu¬ reau of Mines. Manila, P. I. Abbott, Agatin Townsend, (J'40) Jr. Engr., Phelps Dodge Corp., Morenci Branch, Morenci. Ariz. Abbott, Clarence E., (M'04) Civil Engr., V.P., Ten¬nessee Coal Iron & R.R.. Co., 1542 Brown -Marx Bldg.. Birmingham, Ala. Abel, Raymond L., (M'28) Chem. Engr., Command¬ing, Officer, Pittsburgh Chem. Warfare Procurement Dist., American Bank Bldg., Pittsburgh. Pa. Abel, Walter D., (M'32) Alin. Engr.. Div. of Cor¬porations, State of Calif., 403 California State Bldg., Los Angeles, Calif. Abele, Louis T., (M'31) 423 3rd Ave., Decatur, Ga. Abell, Leo M., (M'31) Mill Supt. & Met., Emperor Gold Min. Co., Led., Vatnkoula, Fiji Islands. Abernathy, G. E., (M'38) Geol., Kansas State Geol. Survey, Pittsburg, Bans. Abernathy, Jack H., (M'40) Peer. Engr., c/o Superior Oil Corp., National Bank of Tulsa Bldg., Tulsa, Okla. Aborn, Robert H., (M'10) Asst. Met., Research Lab., U. S. Steel Corp., Lincoln Highway, Kearny, N. J. Abraham, A. W., (M'39) Peer. Engr., Richfield Oil Corp., 555 S. Flower St., Los Angeles, Calif. Abramowitz, William L., (J'40) Chem., Industrial Inventions, Inc., 103 Foster Se., Peabody, Mass.

Jan 1, 1942

By J. H. Schulman, M. H. Buckenham

R. W. Christy (Manager of Sales, Sanitary Engineering Equipment, Link-Belt Co.) and C.D. Rubert (Barrett, Haentjens & Co.) — Messrs. King and Schepman have presented an excellent paper which outlines the general practice in the design of thickener mechanisms. Lifting devices, controls, special applications and underflow pumping arrangements have been reviewed in detail. Pumping arrangements were illustrated which eliminate the need for an expensive tunnel beneath the thickener floor. Most of those illustrated have the common feature of a relatively long underflow suction line extending from the hopper floor to the pump located on the bridge at the periphery of the tank. The authors limit these arrangements to comparatively dilute or thin slurrys. It is implied that dense and coarse concentrates, which are difficult to pump, cannot be handled unless a tunnel is constructed. Fig. 1 shows an underflow pump arrangement which negates the need for a tunnel but which permits the operator to convey a heavy dense slurry. The pump is mounted directly on the fixed hoist platform and the impeller is located at the base of the steel center column. Priming water is not needed. The column

Jan 1, 1963

EDWARD W. PARKER,* Philadelphia, Pa. (written discussion ?).-The two papers on coal-mine costs and pride fixing that Mr. Norris has contributed to the Transactions possess as much general interest and are of as much value to the coal-mining industry as any papers that have been presented in recent years. Until recently one of the troubles with the coal business, and especially the bituminous branch of it, has been that because of the lack of a uniform system of cost accounting (many operators, I regret to say, not having had any system at all), the industry as a whole may be said not to have known where it was at. The system adopted by the Federal Trade Commission may not be absolutely perfect but it has accomplished something in that it has compelled a uniform method of reporting and tabulating costs giving results of these compilations which are comparable. The Institute and the coal-mining industry owe a vote of thanks to, and of confidence in, Mr. Norris and his two associates on the Engineers Committee of the Fuel Administration, Messrs. Garnsey and Allport, for the great work they have done in interpreting the results compiled by the Federal Trade Commission, not to speak of the personal sacrifices made by them in giving their services to the government. Those who have read Mr. Norris' paper will probably join me in wishing he had brought out a little more fully the real meaning of the charts so far as they indicate the difference between the cost of producing a ton of anthracite and the price the operators receive for their product. Mr. Norris could have done this more satisfactorily than anyone else. It seems to me that particular attention should be drawn to the fact that, according to these charts, and the tables accompanying them, not less than 25 per cent. of the total output of anthracite, whether "company" or "individual," during the period covered by Mr. Norris' paper,

Jan 4, 1919