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By N. J. Grant, B. C. Giessen, R. Koch

The system Nh-Ir was investigated over the complete concentration range by metallography and X-my techniques, using forty one alloys. The solubility limits of terminal and intermediate phases and the solidus temperatures were determined. Five intermediate phases were found: a Nb3Ir, cubic, Cr3O type; tetragonal, ofecr thorhomhic, isostruc-turn1 with (ta-Rh); and a Nhlr3. cubic, AuCu, type. a Nb3lr and a Nbfr3 melt congruently; three eutectic and three pentectic reactions occur. The phase diagram of the Nb-Ir system had not been fully treated in the literature; only surveys of intermediate phases were found.1"5 In this study, the details of the phase boundaries were investigated as well as the crystallography of the intermediate phases. EXPERIMENTAL METHODS The experimental procedures such as arc melting of powder compacts, heat treatments, solidus measurements, X-ray, and metallographic observation were identical with those used in the work on the Nb-Rh phase diagram.&apos; They will therefore not be repeated here except where the conditions differed. The purity of the niobium powder was as stated in Ref. 6; the iridium powder of 99.9+ pct purity from J. Bishop and Co., Malvern, Penn., did not contain impurities exceeding 100 ppm, except rhodium (200 ppm). The melting points and vapor pressures of both elements are very similar. This fact contributed to a very small weight loss on melting and facilitated preparation of homogeneous alloys. As shown in Ref. 6 for Nb-Rh, no oxygen pick-up exceeding 200 ppm had to be considered; this was regarded as valid also for Nb-Ir. A total of forty one alloys were used in the determination of the phase diagram; their concentrations are shown in Fig. l, which presents the phase diagram. The concentration limits as determined by the weight-loss method averaged <0.2 at. pct, and never exceeded 0.5 at. pct. Heat treatments were carried out as described in Ref. 6. Depending on the concentration, only tantalum, tungsten, or iridium containers were employed, avoiding oxide crucibles altogether. Alloys from 0 to 25 and from 65 to 100 at. pct Ir were homogenized at 2095°C for 15 hr, intermediate compositions from 25 to 65 at. pct Ir for 65 hr at 1780°C. A typical annealing-time schedule is presented in Table I. Solidus points were measured as described in Ref. 6 with the modification that samples rich in niobium were held between pieces of tantalum foil and samples of high iridium concentrations were held between rhenium platelets or in iridium wire. After each run it was ascertained metallographically that no reaction with the holder had occurred. Rhenium was selected as holder material after it had been shown in separate tests that the melting points of Re-Ir alloys rise continuously from 2440°C. Metallographic examination was carried out as described in Ref. 6, and the same procedure and etchants were used successfully. While metallographic discrimination between a Nb3lr and o was easily possible, X-ray diffraction was necessary to separate al and ct2. X-ray powder patterns were taken and evaluated as for Nb-Rh6 yielding the error limits indicated in Table 111, to be introduced later. For the determination of the invariant reactions and phase boundaries, the same techniques as for Nb-Rh6 applied. The general accuracy of invariant concentrations is regarded as somewhat higher than for Nb-Rh due to the small slope of most solvus lines.

Jan 1, 1964

By JAMES GAYLE

(Presented at the Washington meeting, May 3, 1905, and simultaneously sent to the Iron and Steel Institute, for presentation at the meeting of that Society in London, May 11, 1905.) IT is to be regretted that the data respecting the use of dry-air blast, which was presented to the Iron and Steel Institute at its meeting in the United States, in October, 1904, should. have been restricted to the period from August 25th to September 9th inclusive, and from September 17th to 30th inclusive. In order to present the paper at all it was found necessary to limit the record of operations to the period above stated. In the discussion of the paper it would appear from the conclusions of some participating therein, that they have been placed at some disadvantage in considering the economies obtained through the use of dry-air blast, by reason of the data covering such a short period. It is the purpose of this communication to present in detail the record of operations of the Isabella Furnaces from November, 1904, to March, 1905, inclusive, as shown by the furnace-records. The month of October, 1904, is not included, as the furnace using dry-air blast was stopped several times for repairs, and while the record was a very good one considering these interruptions, yet it was not a continuous one. The record for Furnace No. 1 using dry-air blast, and the comparison with Furnace No. 3 using natural air for the month of November, 1904, is set forth in Table I. By a reference to my former paper it will be noted that the month of November is the beginning in this country of the winter period, when the atmosphere decreases rapidly in humidity. The month of October being the transition month in the autumn and April in the spring, and furnaces using natural air approach more closely, from November on, to the conditions obtained by the use of dry-air blast. The data given in

Jul 1, 1905

By W. H. McFarland

The mechanical properties have been determined for a large number of alloy-free martensitic steels with carbon contents ranging from 0.08 to 0.20 pct and with manganese contents of about 0.4 to 0.5 pet. These steels were tested 1) as water-quenched, 2) after quenching, temper rolling, and tinning, and 3) after tempering treatments which involved temperatures from 400o to 1300oF and times from 1 min to 8 hr. The majority of these tests represent steel from commercial-size coils, i.e., strip 32 in. wide, coil weights up to 20,000 16, and steel thicknesses from 0.0055 to 0.024 in. As a result of these treatments, it has been shown that as-quenched low-carbon alloy-free steels can be produced with tensile strengths ranging from 140,000 to 220,000 psi and tensile elongations from 3.0 to 4.0 pet in 2 in. The tensile strength of the as-quenched martensites can be represented by the equation, tensile strength (ksi) = 119 + 560 (wt pet C). The response to tempering of these steels is related to previous work by Muir, Averbach, and Cohen and by Grange and Baughman. Strain aging of low-carbon martensite has also been investigated. If low-carbon steels are defined as those steels with a maximum carbon content of 0.2 pet, it is found that the literature on low-carbon, alloy-free martensites contains little data on the mechanical properties of these steels. However, the following facts concerning low-carbon alloy-free martensites seem firmly established:&apos;-&apos; 1) The major factors in controlling the strength of the martensite appear to be a) fine structure, b) the internal strain resulting from the transformation, and, particularly, c) the amount of carbon in solid solution. 2) In low-carbon steels, the martensite is auto-tempered and is in the form of needles with only minor amounts of internal twinning, whereas the martensite in high-carbon steels forms as plates which are internally twinned on a fine scale. 3) Care must be taken in comparing the results of work that has been done on low-carbon steels with varying amounts of alloying elements to data on plain carbon steels. As has been noted by Irvine, Pickering, and Garstone,6 alloying elements generally lower the martensite start temperature and, thereby, decrease the amount of auto tempering obtained during the quench. This makes it difficult to

Jan 1, 1965

By J. E. Gruzleski, O. Knacke, M. J. Meixner

The evolution of CO from small specimens of solidifying steel was investigated using a thermobalance technique. Gas evolution begins in the temperature range between 1400" to .1450°C. This behavior is independent of the initial carbon content and the cooling rate. At a constant temperature above 1220°C, the rate of gas evolution is temperature independent. Out-gassing of the specimen is thought to proceed through small channels formed by the coalescence of bubbles between dendrites. LIQUID metals have a higher solubility for gas than the solid. During freezing, these gases form bubbles which may either escape or remain trapped in the solid. Recent work1 on the evolution of oxygen from solidifying silver showed that the gas is not liberated until a large fraction of the melt has solidified, and that the gas is evolved in an almost explosive manner. Because of the commercial importance of CO evolution in solidifying steel, a similar investigation was undertaken to study the mechanism of gas liberation in steel. EXPERIMENTAL The thermogravimetric method of Knacke and eixner1 to follow gas evolution by weight changes was employed. Weight differences of 0.1 mg could be reproducibly measured on specimens weighing 2.5 g. These specimens were taken from alloys with varying carbon contents from <0.01 to 0.11 wt pct and <0.01 wt pct of each of silicon, manganese, and aluminum. Specimens contained in 8 mm ID magnesium alumi-nate crucibles were heated to 1550°C under 1 atm of very pure (99.995 pct) CO with a tungsten resistance furnace. The specimen temperature was measured with a Pt-Pt/Rh thermocouple located directly beside the crucible. It is felt that the temperature thus measured was within 5" to 10°C of the specimen temperature since on fusion the weight of the specimen increased due to uptake of CO, and this weight increase was always observed to begin within the temperature range of 1530" to 1540°C. Even after 3 hr there was a small weight increase with time indicating that the molten specimen was not completely saturated with CO. Therefore, complete saturation was not attempted, and all specimens were simply held for 3 hr at 1550°C before cooling. Two types of cooling experiments were performed. One consisted of continuous cooling at linear rates from 5°C to 20°C per min down to 1020°C. The second type of experiment involved continuous cooling at 10°C per min to a predetermined temperature, and then holding the specimen at this temperature for a certain time. During all of these experiments, the sample weight was recorded as a function of time and temperature. OBSERVATIONS Continuous Cooling Experiments. No gas evolution was detected above 1450°C. The initial weight decrease always occurred between 1400" and 1450°C with the average at 1430°C. With further cooling, gas evolution continued to about 1150°C. Between this temperature and 1020°C no further outgassing was observed. This behavior did not seem to depend on the initial carbon content nor on the cooling rate in the range investigated. Typical patterns of gas evolution are shown in Figs. 1 and 2 for different initial carbon levels and cooling rates. The total amount of gas liberated during solidification varied with the rate of cooling. The total weight change on continuous cooling at a rate of 10°C per min

Jan 1, 1970

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&apos; 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&apos; HZ =-6600(1 - xA1)&apos; + 4400(1 - XMf cal SCHNEIDER and toll&apos; have used a transpiration technique to measure the vapor pressures of magnesium over Mg-A1 alloys between 544" and 594°C. amsstad,&apos; 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&apos; 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 &apos;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

By E. T. Turkdogan

This is a compilation and a critical review of the data on the Fe-Ca-0 ternary system. Using the results on the reductiorz-equilibria, an oxygen potential diagram is drawn for the greater part of the system. A number of univariant systems and invariant points, not determined experimentally, are evaluated by making use of the theorem on univariant curves intersecting at an invariant point. The formation of solid solutions and ternary compounds and the crystal structures of some of the phases in the composition-diagram are given for a feu! temperatures. DURING the past thirty years there has been a continued interest in the study of the Fe-Ca-0 system. A detailed literature survey made by white1 in 1943 indicated that further work was required to clarify the phase relationships; in fact, the work carried out in the subsequent years, reviewed by Burdese2 in 1954, made a valuable contribution to a better understanding of this subject. Most of the data were obtained by the step-wise reduction of mixtures of iron oxides and calcium ferrites. However, there is some uncertainty about the phase relationships in this system, arising mainly from insufficient use of thermodynamic concepts in the construction of phase diagrams. In this paper an attempt is made to establish the invariant points from the available data. OXYGEN POTENTIAL DIAGRAM Schenck and coworkers3,4 were the early investigators who studied part of this system by the step- wise reduction method and suggested the formation of two ternary compounds, CaO.FeO.Fe2O3 and 2Ca0.5Fe0.2Fez03, the latter being referred to as point X. They also deduced from their results that the phases Y (8.74Ca0.32.5Fe0.8.74Fe2O3 and Z (2.02CaO-97.98FeO) were formed near the w?stite corner of the system. Martin and voge15 postulated the existence of the compounds CaO.9FeO and 4Ca0.3Fe3O4; the former is very close to the composition of point Z and the latter to that of CaO.FeO-Fe2O3. The most valuable contribution to the presen knowledge on this system was made by Cirilli and Burdese6-8 who showed by X-ray and chemical anal yses that there were two ternary compounds, CaO-Fe0.Fe2O3 and CaO.3FeO-FezO3; the former is the same as that suggested by Schenck et al. and the latter is close to their point X. The results of Cirilli and Burdese show that the phases Y and Z postulated by Schenk et al. are solid solutions of calcium oxide in w?stite. In most of the above-mentioned reduction-equilibria measurements carbon monoxide-carbon dioxide mixtures were used and in a few cases hydrogen-water vapor mixtures were employed. Using the

Jan 1, 1962

By Roy G. Mead

BECAUSE of its magnitude, and the type of occurrence, the deposit of boron minerals in the Kramer district, Kern County, California, is unlike any other in the world. Discovery of this vast deposit has brought about many changes in the borax industry, so a discussion of the geology, and the occurrence, would not be complete without a brief history of the development of the borax industry. Until the discovery of boron minerals in the desert regions of California and Nevada some seventy years ago, borax was imported from Tibet and India, principally for medicinal purposes, at almost prohibitive prices. Following the discovery of commercial deposits of boron minerals in California and Nevada, and the subsequent development of new uses for borax and boric acid, the consumption has steadily increased until today borax is used in some form or other in every household.

Jan 1, 1933

By R. Schuhmann, E. J. Michal

Experimental measurements are reported for the oxygen pressures of iron-silicate slags in equilibrium with solid silica. CO2-CO mixtures were bubbled through the slags in silica crucibles to find equilibrium values of p co2/p co over the entire composition range of silica-saturated slags at 1250°, 1300°, and 1350°C. From the data, the activity vs. composition relationships were calculated for O, FeO, and Fe. SLAGS composed primarily of silica and iron oxides have particular practical importance in copper smelting,&apos; in acid steelmaking, and in accounting for the service behavior of silica refractories. These slags all contain both ferrous and ferric iron, so that, strictly speaking, they are ternary or three-component liquid solutions. For convenience, the components may be taken as the three oxides, FeO, Fe2O3, and SiO2. The constitution of the FeO-Fe,O,-SiO, system at slagmaking temperatures has been studied in a recent investigation described in a separate paper.&apos; This work showed the compositional ranges of iron-silicate melts at temperatures up to 1450°C and also the temperature-composition relationships for melts in equilibrium with various solid phases, including iron, wüstite, magnetite, and silica. Broadly speaking, the compositions of iron-silicate melts at a given temperature should be thought of as varying over a two-dimensional field. In the first place, the silica/total iron oxide relationship varies from maximum silica for silica-saturated melts to minimum silica for wüstite-saturated melts or, at higher temperatures, to zero silica for straight iron oxide melts. In copper smelting, for example, the converter slags approach the low silica limits while the reverberatory-furnace slags have intermediate silica contents, perhaps approaching silica saturation in some circumstances. Liquids formed in the pores of silica refractories presumably are close to silica saturation. The second type of composition variation is in the ferric/ferrous relationship, which depends on how oxidizing or how reducing the process conditions are. Relatively reducing slags, such as acid-steelmaking slags, are lower in ferric oxide and ap- proach saturation with metallic iron. Oxidized slags, such as copper-smelting slags, contain larger percentages of ferric oxides and approach or reach saturation with magnetite. Since these two kinds of compositional variations are closely related to two general properties of interest for all metallurgical slags, basicity, and oxidizing power, it is hoped that the thermodynamic study of iron-silicate slags eventually will throw further light on the significance and nature of these long-recognized but as yet poorly understood slag properties. Measurements of oxygen activity as a function of slag composition, using CO-CO2 gas mixture to fix oxygen activities, afford an experimentally convenient approach to the study of the thermodynamic properties of iron-silicate slags. In a preceding investigation,³ his approach was used in a systematic study of iron-silicate slags in equilibrium with solid iron. The present paper gives the results of a similar study of the iron-silicate slags in equilibrium with solid silica. The experimental work consisted in the determination of CO2: CO ratios in gas mixtures at equilibrium in the system: gas: liquid slag: silica Determinations were made at temperatures from 1250° to 1350°C for slags ranging in composition from iron saturation to magnetite saturation. Also, equilibrium CO,: CO ratios and slag compositions were determined for the univariant systems: gas: liquid slag: silica: iron gas: liquid slag: silica: magnetite Experimental Methods The experimental procedure was essentially the same as that used in the previous study of iron-silicate slags saturated with solid iron," but in order to work with the silica-saturated slags an all-silica crucible assembly was used. A liquid slag was prepared from pure prefused stock materials and brought to equilibrium with the silica crucible at the desired temperature. Then a mixture of CO2 and CO was continuously bubbled through the melt

Jan 1, 1953

By Strathmore R. B. Cooke

On the basis of experiments con- ducted on quartz using a bubble pick-up method, it was shown in an earlier paper1 that this mineral will preferentially adsorb hydrogen, calcium, or sodium ions, depending on the relative concentrations of those ions in the solution in which the quartz is immersed. For quartz particles ranging in size from 0.2 to 1 mm, it was demonstrated that the concentration of calcium in solution (assumed present as ions) necessary to completely activate quartz for flotation is given by the expression: In this expression, ionic concentrations are in mols per liter. It was further shown that the pick-up method is apparently more sensitive to changes in reagent concentration than the standard captive-bubble method, and that induction times are apparently much reduced. Since completing these earlier tests, a new type of cell has been constructed; this is shown in Fig 1 and 2. In Fig 1, A is a ground joint, B is a ceutral tube reaching to within a few millimeters of the bottom of the cell, and C is a stopper which may be removed for re- agent addition, and serves the further purpose of excluding carbon dioxide from the air during the test. The entire cell is constructed of Pyrex glass, and does not give the trouble experienced with the earlier cell, in which activating ions were released from the glass at high pH values. The only critical factor in the construction of the cell is the clearance between the central tube and

Jan 1, 1949

By AIME AIME

[SECRETARY&apos;S NOTE.-Since the Committee on Publication of United Engineering Society, will issue a memorial volume re¬porting these proceedings in full, an outline only will be here given. The sessions were held in the Main Auditorium.¬R. W. R.] COMMITTEES. EXECUTIVE.-J. W. Lieb, Jr., Chairman; C. W. Rice, Secretary; John Hays Hammond, Chas. Wallace Hunt, F. R. Hutton, Charles Kirchhoff, T. C. Martin, E. E. Olcott, Chas. F. Scott, Samuel Sheldon, Ambrose Swasey. INVITATIONS.-R. W. Raymond, Chairman; Charles Kirchhoff, Secretary; A; C. Humphreys, Robert W. Hunt, L. B. Stillwell. PROGRAM.-A. R. Ledoux, Chairman; C. W. Rice, Secretary; Theodore Dwight, Chas. Wallace Hunt, T. C. Martin, Ralph W. Pope, Joseph Struthers. WAYS AND MEANS.-James Douglas, Chairman A. R. Ledoux, Secretary; H. R. Brown, J.-M. Dodge, C. L. Edgar, John Hays Hammond, W. M. McFarland, E. E. Olcott, Samuel Sheldon, J. G. White. HISTORICAL AND PUBLICATION PRESS.-T. C. Martin, Chairman; Albert Spies, H. H. Suplee.

May 1, 1907

Jan 1, 1887

By William B. Plank

FOR the third consecutive year, I have collected the data on enrolment and employment of graduates from the schools in. the United States and Canada that grant degrees in mineral technology. The data were collected in the same way as formerly; namely, by questionnaire, dated Jan. 5, 1935, and are therefore comparable with the figures reported for former years. This year, along with the names of the 48 schools in the United States and the six in Canada, are listed the courses offered and the degrees granted by each, school, together with the names of the professors in charge. The names and addresses of the four schools in Mexico are also given. The list is on pages 450-1, which should he valued as a directory by those interested in mineral technology education. So far as is known, this is the most complete and up-to-date list that has ever been published.

Jan 1, 1935

By R. W. Mancantelli, J. R. Woodward

IN 1947 a large low grade deposit of uranium was located in the northwest corner of Saskatchewan, in the Beaverlodge property of Eldorado Mining & Refining Ltd. Most of the values occur as thin seams and as coatings on other minerals, and the ore, which is light and friable, is not amenable to the usual gravity methods of concentration. The acid leaching process developed to retreat the company&apos;s Port Radium tailings was also impractical, as the percentage of carbonates is high and the percentage of sulphides relatively low. Construction of the mill building and installation of equipment, both scheduled for 1952, awaited selection of a satisfactory ore dressing process on or before Oct. 1, 1951. An extensive research program on dressing of ores from the Ace mine therefore was undertaken by the Mines Branch in Ottawa, a research team at the University of British Columbia, and an ore dressing group at the company&apos;s Port Hope refinery. Pilot plant operations were conducted at the Ottawa plant of Sherritt Gordon Mines Ltd. under the general direction of C. S. Parsons, consultant on metallurgy and ore dressing for Eldorado. In mid-September, having compared results of the several research programs, Dr. Parsons recommended a process employing a carbonate or basic leach. He reported that, while the chemistry of the process had been proved, engineering of the flowsheet was incomplete, and he suggested that under normal conditions further pilot plant work at the Ace mine might be profitable. However, since this would involve a delay of 12 to 18 months in bringing the property into operation, he recommended that design of the concentrator proceed immediately. Concentrator capacity was determined by two considerations: 1) the amount of ore then available and 2) the expectation that continued improvements would be made in the ore dressing process as a result of the intensive research being carried out by the Mines Branch of the Department of Mines and Technical Surveys. As these improvements could affect both the chemistry and the en-

Jan 1, 1956

By William B. Millar

IN ONTARIO development of the gold mines is being rapidly pushed, while the intensity of the search for new mines has probably not been equaled at any time in the past. Even to outline the results of recent prospecting activity in Ontario would be a big undertaking, but it would be timely and, I hope, interesting to Institute members to review some generalities regarding the work of the prospector and then to discuss in some detail the growth of Ontario&apos;s most promising prospect area, the Swayze district, where serious mining operations are already under way. Probably no one writing about prospectors and pros¬pecting can resist hoping that his article will not reach the eyes of a certain portion of the uninformed general public and cause a further influx of "prospective prospectors" into any given area. It is somewhat mystifying how so many people reach the conclusion that prospecting is in

Jan 1, 1933

February 20th, 1872. THE Institute assembled on Tuesday evening, in the building of the University of Pennsylvania. In the absence of President Thomas, Vice-President Raymond occupied the chair. The Institute was welcomed in an eloquent and thoughtful address by Prof. J. P. Lesley, to which Mr. Raymond responded. Invitations were announced from the proprietors of Sellers&apos; Tool Works, Whitney&apos;s Car-wheel Works, the Baldwin Locomotive Works, Lewis & Brothers&apos; White Lead Works, the Southwark Foundry, Harrison&apos;s Boiler Factory, the University of Pennsylvania, and the Academy of Natural Sciences. The following gentlemen, being duly recommended by the Council as members and associates, were unanimously elected Alexander, John S., - Philadelphia, Pa. Biddle, E. R., - New York. Britton, J.. Blodget, - Philadelphia, Pa. Brooks, Maj. T. B., - Marquette, Mich. Brown, D. P., - Pottsville, Pa. Canfield, Edw., - Dover, N. J. Cogswell, W. B., - Franklin IronW&apos;ks, N.Y. Cornwall, Prof. H. B., - New York. Edwards, Daniel, - Danville, Pa. Estabrook, John D., - Philadelphia, Pa. Firmstone, William, - Easton, Pa. Fritz, John, - Bethlehem, Pa. Gignoux, Charles, - New York. Grant, E. M., - Tuskegee, Ala. Humphreys, A. W., - New York. Ingham, W. A., - Philadelphia, Pa. Keyes, W. S., - Eureka, Nev. Kimball, Dr. J. P., - New York. Law, Charles, - Pittston, Pa. Neilson, W. G., - Philadelphia, Pa. Newberry, Prof. J. S., - New York. Pearse, John B, - Steel Works P. O., Pa. Ricketts, P. De P., - New York. Scranton, Col. Charles, - Oxford, N. J. Sontag, Hugo, - Cologne, Prussia. Steele, Thomas C. - Summit, Pa. Wharton, Joseph, - Philadelphia, Pa.

Jan 1, 1873

By R. Stratton-Crawley

Flotation-related processes utilizing an oil phase for processing fine mineral particles have been described and various applications discussed. The problems associated with the techniques are varied, but may be summarized by the following areas; (1) applicability to fine particle beneficiation, e.g. collector extender and emulsion flotation. (2) major &apos;mechanical&apos; problems, e.g. emulsion breakage and oil recovery in oil flotation. (3) complex interfacial chemistry, e.g. empirical nature of pigment flushing .

Jan 1, 1979

By T. A. Rickard

The writing that is effective is woven with a fine texture into an agreeable pattern; it is free from knots, loose threads, and stray fluff. The instrument that weaves this literary fabric, whether it produce a homely sock or a lordly tapestry, a simple story or a learned &apos;Itreatise, is a disciplined intelligence, as sure as a steel needle, as precise as a swift loom. The simile breaks down at this point, for the product of the pen is instinct with the human spirit and therefore transcends in beauty anything made by a mere machine. If words are to be woven into eloquent meaning, they must be well knit. Upon the relation of words to each other and of groups of words to other groups, known as phrases, clauses, and sentences, depends the success of writing as a means of trans¬mitting thought from man&apos; to man. To be understood beyond question, you should know not only what your words denote but how to build your sentences; you must not only choose your words aright but construct your sentences properly. A sentence is a combination of words that makes complete sense; it says something about something. &apos; A clause is a subordinate sentence or a sentence within a sentence. A phrase is a group of words without a predicate; it makes sense, but not complete sense. For example: I shall wait for a few minutes before I go home: The whole statement is a sentence; "I shall wait" and "before I go home" are clauses; "for a few minutes" is an adverbial phrase. The orderly arranging of words and of combinations of words is called `syntax&apos;; and from the original Greek form, ouvaeis (suntaxis), is derived the Greek name for an editor,

Jan 1, 1931

By A. A. Jr. Smith, J. S. Smart

The controlled amounts of phosphorus, arsenic, sulphur or selenium found in commercial coppers perform a variety of highly useful functions. Indeed, a large segment of modern copper technology is essentially dependent upon the presence of one or more of these elements. Consequently, the literature contains many references to their effects but the scope is broad and has been only partly covered. New data are presented herewith directed toward a better understanding of the basic behavior of these elements in copper, with particular emphasis on the composition range o to 0.05 per cent. These data are a part of a general program of research on the effects of impurities on the properties of oxygen-bearing and oxygen-free copper, other portions of which have been reported previously. Schematically, the behavior of individual elements is determined from measurements of conductivity and softening temperature,&apos;v2 and the binary alloys employed are synthesized from high-purity copper in order to eliminate interference from the effects of extraneous impurities. Alloys of selected composition were first prepared in the oxygen-free form by continuously casting the melts in the form of %-in. diameter rod. Oxygen was added subsequently to portions of the alloys, either by remelting or by diffusion at 8jo°C. from a surface scale. Test wires wcre drawn one B. and S. number per pass, using four 30-min. 600°C. anneals at 0.3125, 0.257, 0.204 and 0.162 in., and a final cold reduction of 75 per cent to 0.081 in. Oxygen-bearing slugs made by remelting nere hot-rolled to 4ia in.. drawn to 0.162 in., annealed for 30 min. at 6o0°C. and cold-drawn 75 per cent to 0.081 inch. The alloys containing phosphorus, having been compounded very early in the program, were prepared in the form of 3i6-in. rod, and processed to wire with only the last three intermediate anneals listed above, all of these having been conducted in commercial nitrogen. In addition, the conductivity anneals on these alloys were also performed in the same atmosphere, and the small amount of oxygen present as an impurity in the gas resulted in some loss of accuracy at temperatures of 700&apos; to 8o0°C., as will be shown later. Subsequently, the anneals for all oxygen-free alloys were conducted in hydrogen to prevent oxidation, and purified nitrogen was employed only for oxygen-bearing samples. All conductivity anneals wcre of one hour duration followed by a rapid quench in 10 per cent HZSO*. Effect of Phosphorus The widespread use of phosphorus as a deoxidant has resulted in universal appreci-

Jan 1, 1946

By A. A. Jr. Smith, J. S. Smart

The controlled amounts of phosphorus, arsenic, sulphur or selenium found in commercial coppers perform a variety of highly useful functions. Indeed, a large segment of modern copper technology is essentially dependent upon the presence of one or more of these elements. Consequently, the literature contains many references to their effects but the scope is broad and has been only partly covered. New data are presented herewith directed toward a better understanding of the basic behavior of these elements in copper, with particular emphasis on the composition range o to 0.05 per cent. These data are a part of a general program of research on the effects of impurities on the properties of oxygen-bearing and oxygen-free copper, other portions of which have been reported previously. Schematically, the behavior of individual elements is determined from measurements of conductivity and softening temperature,&apos;v2 and the binary alloys employed are synthesized from high-purity copper in order to eliminate interference from the effects of extraneous impurities. Alloys of selected composition were first prepared in the oxygen-free form by continuously casting the melts in the form of %-in. diameter rod. Oxygen was added subsequently to portions of the alloys, either by remelting or by diffusion at 8jo°C. from a surface scale. Test wires wcre drawn one B. and S. number per pass, using four 30-min. 600°C. anneals at 0.3125, 0.257, 0.204 and 0.162 in., and a final cold reduction of 75 per cent to 0.081 in. Oxygen-bearing slugs made by remelting nere hot-rolled to 4ia in.. drawn to 0.162 in., annealed for 30 min. at 6o0°C. and cold-drawn 75 per cent to 0.081 inch. The alloys containing phosphorus, having been compounded very early in the program, were prepared in the form of 3i6-in. rod, and processed to wire with only the last three intermediate anneals listed above, all of these having been conducted in commercial nitrogen. In addition, the conductivity anneals on these alloys were also performed in the same atmosphere, and the small amount of oxygen present as an impurity in the gas resulted in some loss of accuracy at temperatures of 700&apos; to 8o0°C., as will be shown later. Subsequently, the anneals for all oxygen-free alloys were conducted in hydrogen to prevent oxidation, and purified nitrogen was employed only for oxygen-bearing samples. All conductivity anneals wcre of one hour duration followed by a rapid quench in 10 per cent HZSO*. Effect of Phosphorus The widespread use of phosphorus as a deoxidant has resulted in universal appreci-

Jan 1, 1946

By W. G. Sinclair

THE North Texas district presented in this paper includes the counties of Archer, Baylor, Clay, Cooke, Foard, Hardeman, Jack, Knox, Montague, Wichita, Wilbarger and Young. It corresponds with the Texas Railroad Commission&apos;s district No. 9. Table I conforms with the nomenclature of pools as designated by the Commission. Most of the oil and gas produced in this region, generally referred to as the Red River uplift, comes from the Pennsylvanian strata. In recent years, however, increasing amounts are being developed in both the Mississippian and Ordovician.

Jan 1, 1946