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ROBERT VAN ARSDALE NORRIS, who died at his home at Wilkes-Barre, Pa., on April 20, 1928, was born at Newark, N. J., on May 2, 1864, of parents who were direct descendants of such sterling New Eng-landers as Governor William Bradford, John Alden and Timothy Dwight. He went to the Collegiate School in New York and then to the Colum-bia School of Mines where he graduated with the class of 1885, having among class-mates A. S. Dwight, E. N. En-gelhardt, H. L. Hollis, G. B. Lee, Richard Moldenke, Wil-bur Sanders, Joseph Struth-ers, E. A. Wiltsee, and I. H. Woolson. His marked ability even among so many men of unusual ability caused him to be chosen as assistant to Pro- fessor Munroe in the summer school of mining and survey-ing immediately after gradua-tion, and he shortly after was also inspector of dredging operations on the Maurice River improvement work, Millville, N. J. The follow- ing year he worked in the chemical laboratory of Herman Behr in Brooklyn, and toward the end of 1886 he joined the staff of the Pennsylvania R. R. Coal Co. and the Susquehanna Coal Co. as assistant engineer. Six years later he was made principal assistant en- gineer and in 1900 he was made chief engineer of these companies. In 1904, he withdrew from them and estab- lished an office as a consulting engineer at Wilkes- Barre, later taking his son, Robert V., Jr., into partner- ship with him. They acted as consulting engineers for the coal department of the Delaware, Lackawanna & Western R. R. Co., the Lehigh Valley Coal Co., Coke Bros. & Go., Inc., the coal department of the Pennsyl- vania R. R. Co., the Wilkes-Barre & Hazelton R. R. Co., the Sterling Salt Co., and others, specializing in ex- amination and appraisal of coal properties, and also matters of Federal taxation.

Jan 5, 1928

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Jan 1, 1938

By W. M. Parris, P. D. Frost, H. A. Robinson

The effects of hydrogen content and strain rate on the static tensile and notch-rupture properties of the Ti-3Mn-complex alloy heat-treated to differed strength levels were investigated. The extent of embriulement was found to be proportional to the amount of hydrogen present and the strength to which the specimens were heat-treated. The research suggests the possible necessity of specifying lower hydrogen limits than are now allowed when titanium alloys are heat-treated to higher strengths than are presently used. The research also supports a hypothesis advanced earlier for a mechanism of hydrogen embrittlement. MUCH attention has been focused on the effects of hydrogen in in Most of the published in- formation has dealt with the effects of hydrogen on alloys in the annealed or lowest-strength condition. The work of Kotfila and Erbin3 is one of the few exceptions. In view of the fact that heat-treatments are now being used to produce high strength in titanium alloys,' it is necessary that more attention be given to the effects of hydrogen on these alloys in the heat-treated condition. Research was initiated to establish the effects of hydrogen on the properties of the Ti-3Mn-complex alloy at various strength levels. This research, which supplemented that of Kotfila and Erbin, was started because it was found that high-strength tensile specimens of this alloy were strain-rate sensitive. The essential results of the research are summarized in this paper. MATERIALS AND EXPERIMENTAL PROCEDURES Material for this investigation was a 41/2-in.-diam bar forged from a single commercial heat of the Ti-3Mn-complex alloy having the composition given in Table I. The as-received forging was reduced further by forging at 1750°F to 3/4-in. square bars. About one fourth of this material was vacuum annealed at 1400°F for 24 hr to obtain a base hydrogen content of 25 ppm. The remaining bars were hydrogenated to levels of 90, 140, and 260 ppm in a large Sievert's apparatus in the following manner: Four 3/4-in. square bars, 5 in. long, were placed in the reaction chambzr. The chamber was evacuated, heated to 1400°F, and a measured amount of hydrogen was introduced. When absorbtion was complete, as indicated by the drop in pressure, the reaction tube was cooled and the bars removed. Each batch of bars was then sealed in individual evacuated Vycor containers and heated for 24 hr at 1400°F in order to distribute the hydrogen homogeneously. After vacuum-annealing or hydroge nation, the bars were rolled at a temperature (1400°F) below the ß-transus to 1/2 - in. - diam rounds. Groups of the rolled specimens representing each of the hydrogen levels were given the following heat-treatments: 1) One hr at 1300°F, water-quenched. 2) One hr at 1300°F, water-quenched, and aged 8 hr at 1100°F. 3) One hr at 1300°F, water-quenched, and aged 4 hr at 1000°F. 4) One hr at 1300°F, water-quenched, and aged 48hr at 800°F. Heat-treated bars were machined into standard 0.250-in.-diam tensile specimens having 1-in. gage lengths. Throughout the processing and testing of this material, hydrogen analyses were made by vacuum-fusion methods to check for accuracy of hydrogen additions, homogeneity, and possible losses during processing. A summary of these analyses is given in Table II It may be seen that the actual hydrogen contents were reasonably close to the desired levels. In addition, it was noted that the variation in hydrogen content within any one bar did not exceed

Jan 1, 1959

By E. P. Valby

A method is presented in which the hydrocarbon weight fractional analyses of the well effluents from a true gas-tip-portion well and a true dark-oil-ring well furnish the basic data for determining the properties of any mixture of production from the two sources. The effect of injected gas on these properties can be computed. Comparison of similar properties of a given well effluent to the properties of mixtures of the basic well effluents will give the relative amounts of production from the two sources and injected gas. Presentation of Problem Oil fields having an area of gas-cap, or light-oil production, over the dark-oil area present a problem of increasing gas-oil ratios during the production of an oil well. The use of pressure maintenance in a field such as above, or a cycling project, wherein residue gas from an absorption plant is injected into the reservoir, adds to the problem, because a part of the increased gas-oil ratio may be due to the production of injected gas. The usefulness of a means to determine the amount of injected gas in a well effluent led to the development of a method in which well-effluent analyses of a true gas-cap-portion well and a true dark-oil-ring well furnish the basic data needed to determine whether injected gas of a known composition is present in a given well effluent. Development op Method The method presented herein is based upon the principle that if two fluids, or well effluents, having different properties are mixed in known proportions by weight, • the properties of their mixtures can be computed. Conversely, if these basic data are known, the properties of a mixed well effauent can be used to compute the relative amounts of each type of well effluent in the mixture. A convenient way of making these computations is to have the fractional analyses of the base well effluents and mixtures expressed in weight fractions The mathematical equations expressing the properties of mixtures will be developed for a two-component system consisting of the well effluents from the dark-oil ring and the gas-cap area. The added effect of injected gas, a third component, will also be developed. The following assumptions have been made in developing the method: 1. The gas-cap and dark-oil fluids exist initially in separate portions of the reservoir. 2. The fluids in each portion exist in a single phase at pressures above the saturation pressure for the dark-oil fluid. 3. The composition of each fluid is substantially constant throughout its respective portion of the reservoir. 4. Changes in reservoir pressure and temperature will not change the composition of the fluid entering the well bore. 5. The injected gas displaces original gas-cap fluid 100 per cent. •• 6. AS the injected gas travels through a

Jan 1, 1945

By Frederick Prime

In this second supplementary list no titles to which an * is pre fixed hare been seen by tlie compiler; and he will be most thankful to have any omiesisne or inaccuracies in the list sent to hiin to be ptiblisi~cd as a third supplement in the next volume of the actiotra. The author is indebted to Prof. J. J. Stevenson, of New Tork, Prof. P. R. Uhlcr and John 'CV. M. Lee, Esq., of Balti more, and Lloyd P. Smith, Esq., of Philadelphia, for valuable assistance. office, allkntorn iron compaxy, 30 South Third Street, Philadelphia, September 5th, 1881. Alabama. Geologiml Survcy of Alabama. report of Progress for 1879 and 1880, by Eugene A. Smith, State Geologist. Montgomery, 1881. 8vo., 158 pp., and 2 maps. California. Omit Report of Hon. T. Butler Ring, iu sopplemeut I. For Trask's Geology and Illdustrial honrecp, etc., in Supplenlvut I., read Tyson's, etc. Fremont's Menloir on Upper Califijrnia, is also published as XXXth Congress, lat Session. Senate Ms. Doc., No 148, and has a map. For Randall's Report in Supplement I, rend Report of the Special Committee in favor of a Geological Snrvey, subrn-itted by Mr. Randall, April 24th, 1861. n.d., 1851. 8cWo., 19 yp. XXXIst Congress, 1st Session, Sen. Ex. Doc., No. 47, Part 2 [Part 1 is Tyson's Report.) RejW of the Secretary of War in further compliance with the Resolution of the Senate?, calling for Colbies of

Jan 1, 1881

By A. G. H. Anderson, Eric R. Jette

A few years ago, while the writers worked on the constitution of ternary and quaternary alloys consisting mainly of iron, chromium and siliconl,2 some information on microstructures and hardness, not incorporated in the published work, alas obtained. It has not been possible to do any further work on the properties of the alloys. The information possessed is hereby presented for the interest it may have in connection with the constitution of the alloys. Microstructures Referring to the iron-chromium-silicon diagram,' the regions that received most attention were those in which the sigma phase appears. It was found that the mode of occurrence of this phase varied much with the condition under which it mas formed, and the mode influenced considerably the hardness of the alloys. In some slowly cooled alloys, well within the alpha + sigma-phase boundary, sigma occurs in pabterns suggesting a eutectic. The structure of such an alloy is shorn in Fig. 1, showing it to be partly coarsely laminated and partly globular mottled. In other annealed and slowly cooled alloys, the lanlinated structure is entirely absent, and sigma appears in an irregular distribution of sharply cornered elongated areas (Figs. 2 and 3). These areas all possess a more or less mottled structure. A carbide phase is also visible in these two photomicrographs; it is represented by bright white arras of various shapes, sometimes apparently enveloping the sigma. Quenched and aged specimens, whose compositions arc: located near the phase boundary between alpha and sigma + alpha regions, have structures not unlike martensite (Figs. 5 and 6). Fig. 4 shows the structurc of alloy No. 35 as quenched from 1100" C.; it is a typical solid solu-

Jan 1, 1938

By Eric R. Jette, A. G. H. Anderson

A few years ago, while the writers worked on the constitution of ternary and quaternary alloys consisting mainly of iron, chromium and siliconl,2 some information on microstructures and hardness, not incorporated in the published work, alas obtained. It has not been possible to do any further work on the properties of the alloys. The information possessed is hereby presented for the interest it may have in connection with the constitution of the alloys. Microstructures Referring to the iron-chromium-silicon diagram,' the regions that received most attention were those in which the sigma phase appears. It was found that the mode of occurrence of this phase varied much with the condition under which it mas formed, and the mode influenced considerably the hardness of the alloys. In some slowly cooled alloys, well within the alpha + sigma-phase boundary, sigma occurs in pabterns suggesting a eutectic. The structure of such an alloy is shorn in Fig. 1, showing it to be partly coarsely laminated and partly globular mottled. In other annealed and slowly cooled alloys, the lanlinated structure is entirely absent, and sigma appears in an irregular distribution of sharply cornered elongated areas (Figs. 2 and 3). These areas all possess a more or less mottled structure. A carbide phase is also visible in these two photomicrographs; it is represented by bright white arras of various shapes, sometimes apparently enveloping the sigma. Quenched and aged specimens, whose compositions arc: located near the phase boundary between alpha and sigma + alpha regions, have structures not unlike martensite (Figs. 5 and 6). Fig. 4 shows the structurc of alloy No. 35 as quenched from 1100" C.; it is a typical solid solu-

Jan 1, 1938

By S. R. B. Cooke, Iwao Iwasaki, Hyung Sup Choi

John Dasher (Materials and Processes Engineer, Crucible Steel Co. of America, Pittsburgh, Pa.) The authors are to be congratulated for their excellent work, dramatic results, and persuasive explanation on the neglected subject of the temperature variable in soap flotation. The explanation includes why heat is helpful in conditioning and why heat is helpful in flotation. This is a fine start, but I hope the work will be continued to show which is the major effect. In the work of Noman and Dash er(1) it was found that substantially all the benefit of heat came from the conditioning step, and that results were much better if a thick pulp was conditioned hot and then diluted with unheated (or less heated) water for flotation (or agglomerate tabling) than if the same quantity of heat was used to condition and float at some intermediate temperature. In other words, heat for conditioning gives a Rood return, but additional heat for dilution water is near or beyond the point of diminishing return. Strathmore R. B. Cooke, lwao lawsaki, and Hyung Su0p Choi (Authors' Reply) Mr. Dasher'skind comments on our paper are appreciated. In view of the relative simplicity of empirical investigationsof the temperature variable upon conditioning and flotation, it ispuzzling why the subject is so neglected. Our work, being sub sidiary to the main investigation of the effect of structure of fatty acid collectorsupon iron ore flotation, was quite restricted, but we intend to return to the subject as soon as possible. Mr. Dasher's point, that given a certain number of calories it is better to invest them for conditioning in a thick pulp rather than to spread them out for both conditioning and flotation operations, is well taken and cannot be argued. On the other hand there is no question that high temperature during the flotation of iron ores induces superior frothing characteristics, and, in particular, greatly augments the rate of flotation and markedly decreases the time required for "difficult" particles to float.

Jan 1, 1961

By C. R. Dodson, W. T. Cardwell

This paper presents the results of a theoretical and experimental study of the effect of preperforated liners on well productivity. The analysis concerns the rectangular type of slot, either machine or torch cut, which is common in California. Muskatla treated this problem recently in a mathematical analysis of the flow of oil or gas from natural reservoirs into both gun-perforated and slotted liners. This paper presents additional and simplified analytical considerations and conclusions for the slotted liner, the solutions being applicable in the laboratory as well as in the field. An application of the analytical methods to permeability measurements on mounted core samples is given, to show the effects of sealing wax or other obstructions on the end faces of the cores. Results Fig. I 'Ompares the results of some theoretical calculations with the results of electrical analogy experiments performed in the Standard Oil Company of California's Production Technology Laboratory at La Habra, California. Fig. I indicates that the flux into short, "three-dimensional slots" of the relative dimensions encountered in practice is approximately equal to that into full-length, "two-dimensional slots" having the same open fraction of pipe. (The same numbers of slot rows, and the same radius ratio are also implied.) It can be seen from physical considerations that the closeness of this approximation must improve as the ratio of the external radius to the internal radius increases. Therefore, it is possible to calculate the flow into a slotted liner using a simple modification of the Darcy equation: where N is .the number of slot rows and O is the open fraction of the pipe. Fig. 2 shows the results of calculations . using Eq. 28. The most remarkable features of Fig. 2 are the high flux values for very small open fractions of pipe. For instance, with six slot rows and a radius ratio of 500, 74 per cent of the open-hole flux may be obtained with only o.I per cent of pipe Open. Fig. 2 shows that for a given open frac tion of pipe, the flux is greater, the greater

Jan 1, 1945

[Steel, iron which is malleable at least in some one range of temperature, and in addition is either (A) cast into an initially malleable mass ; or (B) is capable of hardening greatly by sudden cooling ; or (C) is both so cast and so capable of hardening. Variety A includes also molten iron which, if cast, would be malleable, as do its two sub-varieties, "ingot-iron" and "ingot-steel." (Tungsten-steel is malleable only when red-hot.)] does not seem to fit perfectly the requirement that it shall include all known varieties of steel and exclude everything else. The first requirement, that it shall be malleable at some temperature, is also possessed by some varieties of gun-iron—that is, mottled castriron, of which cannons have been made in the past by the South Boston Iron Co. and others. Gun-iron also meets the requirement (A) in being cast into an initially-malleable mass. The malleability was indeed not great, nor mas it made use of except to demonstrate the quality of the iron, but it approached in measurable degree that of some of the alloy-steels. As for requirement (B), some puddled-irons having from 0.2 to 0.3 per cent. of carbon may be hardened greatly, although this property is [lot utilized.

Jan 1, 1909

By R. Wild, F. A. Wright

When a blast furnace has a certain defined burden and is operated under fixed conditions of blast temperature, etc., the fuel efficiency is determined by the extent to which the reducing gases can remove oxygen from the burden in the furnace stack. This is determined by two distinct factors: 1) The uniformity of gas-solid contact, and 2) The ease with which oxygen can be removed from individual pieces of burden. This latter is often called burden reducibility. When burdens were poorly prepared the first factor was by far the most important and a study of the reducibility of individual lumps was of rather academic interest. In recent years good burden preparation with emphasis on uniformly sized material has led to greatly improved gas distribution in the stack, and thus the second factor has become much more important and there has been a marked increase in interest in methods of measuring reducibility. This paper explores the Linder method of measuring such reducibility. The measurement of reducibility of burden materials must be carried out under conditions duplicating, as nearly as possible, those of the blast furnace stack. This is very difficult since the blast furnace process is a counter-current one, and thus the initial conditions encountered by the solid (gas temperature, composition, etc.) are the result of heat and mass transfer occurring lower down the stack. Any method of burden testing which does not take this into account is, at least to some extent, based on arbitrary assumptions. In an attempt to study blast furnace reactions under non-arbitrary conditions BISRA adopted the SCICE technique as a method of investigation. This technique has been used with a measure of success.' The SCICE technique, however, was found to be too slow for use as a routine test for burden materials and it was decided to construct additional equipment for burden testing. A test was required which would: 1) Be as realistic as possible. 2) Be quick and easy to operate. 3) Give some indication of the breakdown likely to take place during reduction in addition to a reducibility index. After a critical assessment of the reducibility tests which have been proposed it was decided to adopt the Linder test equipment and procedure as a basis for burden testing. THE LINDER TEST APPARATUS AND PROCEDURE The apparatus which was constructed (Fig. 1) was the same as that described by Linder2 except for minor changes in design. Linder also laid down a test procedure which he had derived from the results of investigations on Swedish blast furnaces. The variations of temperature and gas composition during the test were defined; these are shown diagram-matically in Fig. 2. BISRA's intention was to use the standard temperature and gas composition programmes for testing a variety of burden materials and also to investigate the influence of different programmes on standard burden materials, making use of information from the SCICE apparatus wherever this is possible. Up to the present, effort has been concentrated on the first part of the programme, and work on the second part has only just commenced. For each test 200 g of coke and 500 g of burden material were used. Linder had recommended that the coke and burden material should be between 1 and 1 1/2 in. and this was adhered to in early experiments on ores and sinters. Since the eventual aim of this work was to relate the test results to blast furnace operation, it was decided to carry out subsequent experiments using burden material in the size range used in the blast furnace, as far as this was possible. If the main interest was, for example, a comparison of the products resulting from different methods of agglomeration, then there would be advantages in using burden materials as close as possible to a standard size. After the charge had been placed in the reaction tube and this had been connected to the gas supply, rotation of the reaction tube at 30 rpm was started and the reduction programme was commenced, the gas temperature and composition being manually controlled according to the programme shown in Fig. 2. After the reduction test the charge was cooled in a nitrogen atmosphere. It was then removed from the reaction tube, the coke and burden separated, and the extent of burden breakdown assessed by screening it at 10 and 30 mesh. The extent of reduction was then

Jan 1, 1964

Abel, Charles Edwin, Student, Univ. of California Los Angeles, Cal. '81 Ames, Marshall B., Blaine-Republic Co Republic, Wash. "81 Anderson, Norman John, Student, South Dakota School of Mines Rapid City, S. D. '82 Angst, Robert A., Jr., Student, Michigan College of Min. & Tech Houghton, Mich. '82 Apgar, James William, Student, Lafayette College Easton, Pa. '83 Armstrong, John R. Box 274, Neosho, Mo. '81 Armstrong, Robert H., Student, Lafayette College Easton, Pa. '81 Arnot, Paul H. 608 S. Acacia St., Compton, Cal. '81 Asel, Philip R., Student, Colorado. School of Mines Golden, Colo. '82 Atkins, William Robert, Student, Michigan College of Min. & Tech Houghton, Mich. '82 Augenthaler, Robert L., Student, New Mexico School of Mines Socorro, N. M. '82 Augustine, Robert W., Student, Alaska School of Mines College, Alaska. '82. Avery, Eugene A., Student, Montana School of Mines Butte, Mont. '82 Babcock, Norwood N., Student, South Dakota School of Mines Rapid City, S. D. '82 Baer, Jerome S., Student, Michigan College of Min. & Tech Houghton, Mich. '81 Baker, Robert C., Student, Pennsylvania State College.. 112 E. Beaver Ave., State College, Pa. '82 Baldwin, William C., Student, Univ. of Illinois Urban, III. '81

Jan 1, 1932

Edgar Hall, Tenterfield, New South Wales (communication to the Secretary): Mr. Klepetko* asks for information showing at what percentage antimony and arsenic, as impurities, begin to affect injuriously the quality of brass.

Jan 1, 1899

By Gilbert H. Cady

Those coal mining and preparation engineers and operators who read this article will probably be most concerned with those parts which deal with the applied aspects of coal petrology in the fields of mining and technology. Actually the two categories overlap to such a degree that they are essentially one. The article appears to suggest that there are two points of veiw in the field of applied coal petrology. From one viewpoint the interest is in the attributes of the various macerals (Fig. 4)-vitrinite, exinite, and inertinite-in terms of utilization (when the coal is burned, coked, gasified, hydrogenated, etc.). From the other point of view, assuming that the macerals do possess individuality in behavior, interest attaches to the possibility that coal of a particular type (maceral composition) can be prepared by discriminating methods of preparation and blending. Most of the 29 items listed for mining and technology can be assigned to one or the other of these two categories.

Jan 5, 1958

By H. B. Charmbury, D. R. Mitchell

Recovery of fine coal from solids reporting to wash water has become increasingly important. These solids range from about 28 mesh to 0 and constitute 3 to 7 pct by weight of the feed tonnage to a coal preparation plant. In the past they were usually wasted to streams, but present clean stream legislation makes it necessary to remove them from the wash water and, if economically possible, recover the associated coal as a saleable product. Where these solids are not wasted to streams or to slime ponds they are recovered by thickeners and filters. Since filter cake is often high in ash or sulfur, or both, it is not readily marketed or used. Common practice is to mix it with other plant products, generally slack or cleaned run-of-mine. Uniform blending is difficult, not only because the impurity is usually high, but also because during certain operating periods it is possible to get a concentration of this filter cake in a railroad or barge. At some plants filter cake has been derived from the froth flotation clean-up of Dorr thickener underflow. The operating circuits required for a froth flotation plant make this a comparatively high-cost treatment, and in the last few years experiments have been carried out with bulk oil methods. These also are quite expensive and lend themselves only to special situations. Table I gives some characteristics of thickener underflows for plants in the Pittsburgh area treating Pittsburgh seam coal. It will be noted that there is a concentration of impurities in the -200 mesh sizes.

Jan 1, 1960

By W. M. Johns

The word "Flatland" should read "Flathead" in the title of the paper by Willis M. Johns on page 184 of the June 1962 issue. The correct title is "Belt Series in Lincoln and Southwest Flathead Counties, Montana." In the same paper, reference 12 on page 191, the publication is Bulletin 12, Montana Bureau of Mines and Geology, rather than Bulletin 17.

Jan 1, 1962

By C. P. Mangelsdorf

Introduction The use of frequency of vibration measurements to determine tension has long been accepted by industries that use electrical or stranded cables of wire ropes in their operations. In contemplating how to determine the tension in chords of a roof truss, it seems almost inevitable that a similar approach should be investigated even though there are some important dissimilarities in physical behavior between a chord of a rod-type Birmingham truss and a stretched wire rope. While the dominant feature of both types of behavior is the existence of tension, the bending resistance of the vibrating truss chord cannot be ignored. And it is common to have attached to the chord, pieces of hardware (turnbuckles, extension sleeves, wedge boxes) that represent concentrations of mass not usually found in a vibrating wire rope. Analytical solutions to the problem of vibrating wires or beams can be found in the literature on vibrations (Timoshensko, 1955; Den Hartog, 1956). But in every case, at least one of the ingredients of the vibrating truss chord is missing. The presence of axial tension, or bending resistance, of concentrated masses and of end conditions peculiar to truss chords is a combination that appears not to have been dealt with before, although the techniques for dealing with it are commonly known. The purpose of this note is to report the results of a project to measure and calibrate such frequencies. The work was conducted by the University of Pittsburgh under the sponsorship of the US Bureau of Mines. Field observations Tests were conducted on 24 different truss installations. The first 18 trusses were installed in shale roofs above Kentucky No. 9 seam and Illinois No. 6 seam. The remaining six were placed against the competent sandstone over the Pocahontas No. 3 seam in West Virginia. Chord tension was determined by two electrical resistance strain gages, in series, applied diametrically opposite to one another on the rod before tensioning. Due to the combined effects of inexact gage placement, rod bending and residual torsion in the chord due to tightening, errors in tension as high as 1780 N (400 lb) were reasonably possible. Due to faulty soldering or damage, three of the first 18 trusses and one of the final six were rendered completely unreliable. In addition to strain, the first natural frequency of vibration was observed to the nearest 0.1 Hz. Dimensions recorded included the span between contact points at the bearing blocks (Fig. 1) and the locations and amount of excess rod and rod gap at the wedge box and turnbuckle, respectively.

Jan 1, 1986

By C. B. Alcock, L. I. Cheng

By the use of radiochemical methods for the study of the gas-liquid equilibria at low temperature, and for the determination of the sulfur contents of metal beads which had been equilibrated with H2S/H2 mixtures of known sulfur potential, it has been possible to obtain the liquid solubility and the free energy of solution of sulfur in liquid tin and lead at temperatures between 500°and 680°C. THE gas-liquid equilibrium method has proved in the past to be most successful in the determination of the thermodynamic behavior of dilute solutions of sulfur in liquid metals.1,2 One of the basic requirements for success with this method is that the volatility of both the metal and its lowest sulfide should be small, otherwise sulfide will be deposited at the cool end of the furnace, where it may react with the outgoing gases to form either sulfur-rich lowest sulfide or higher sulfides. The resultant value of the apparent equilibrium constant will then be lower than the correct one. This argument applies even at sulfur potentials below that in equilibrium with a separate condensed phase of the lowest sulfide at the reaction temperature, T. The mass of sulfide which is deposited at the cold end of the furnace, and hence the extent to which further reaction occurs with the outgoing gases, depends on the time taken for equilibrium to be reached between metal and gas. Since this will depend principally on the bulk of the metal phase which is used, one should clearly attempt to uie as small metal samples as possible. These considerations are important in the study of dilute solutions of sulfur dissolved in liquid tin and lead which both have moderately high vapor pressures as metals and form volatile sulfides. The limit on the size of the metal samples which may be used is set chiefly by the difficulties of analysis for very small amounts of sulfur. The oxygen or carbon dioxide combustion method, followed by iodimetric determination of the sulfur dioxide which is formed,has been found to be successful for the determination of small amounts of sulfur in copper, iron, cobalt and nickel.4 This method was unsatisfactory for sulfur dissolved in tin and lead, mainly because the sulfur dioxide was to some extent absorbed by the copious tin or lead oxide deposits which were formed on the walls of the combustion tube. Furthermore some of the sulfur was found to segregate on the surface of the beads as flaky sulfide crystals which would easily be lost in the transfer of a bead from a boat in the gas equilibration apparatus to one in the combustion apparatus. Oxidation in aqueous media to sulfate ion followed by precipitation as barium sulfate was, therefore, adopted as the analytical procedure. The gas-metal equilibrium experiments were all carried out with radioactive sulfur and thus the analysis involved the counting of barium radiosulfate. Furthermore the use of the radioisotope meant that the approach to the gas-metal equilibrium could be followed continuously by gas counting.' The metal beads were held separately in glass crucibles during equilibration and were transferred from the furnace to the beaker for dissolution in nitric acid still in the crucibles, and thus the possibility of sulfur loss by detachment of the sulfide segregates was eliminated. The temperature range of this investigation was 500° to 680°C. EXPERIMENTAL APPARATUS AND METHOD The apparatus consisted of two furnaces placed in series in a gas recirculation system, Fig. 1. One furnace F1, which was vertical was used to heat the alumina crucible, A, holding six metal beads in separate glass crucibles. The beads weighed between 300 and 700 mg each. The crucible assembly was introduced and removed from the furnace mechanically under a stream of oxygen-free argon. The other furnace, F2, was horizontal and was used to heat a cobalt Co9S8 mixture, held in an alumina boat, and made with radiosulfur containing about 1/2 millicurie per g of sulphur. This mixture, which was finely powdered, was used as a source of known H2S/H2 mixtures6 for a given furnace temperature. The recirculation system also contained a gas re-circulation pump (P), an end window Geiger-Miiller counter (N)—placed downstream of F1 so as to monitor the H2S pressure in the gas leaving this furnace— a sample volume for chemical analysis of the gas phase (G), gas drying tubes (D), filling taps and other standard ancillary equipment. The gas sampling volume was principally used in the cali-

Jan 1, 1962

No. 347.-A South African development company will shortly require the services-of a mill superintendent, who has a general knowledge of concentration, particularly of flotation, and is able to take charge of a copper concentrator treating 15,000 tons per month and employing 200 natives and a small number of white men. Salary is £60 per month to start, and the company supplies furnished room or house, including free light, free water and free sanitary service, together with one native house servant. A contract will be made for 6 months, and notice of 3 months by 'either party will be required to terminate the engagement after 6 months. An allowance of £75 for-traveling expenses will be paid on arrival in South Africa to a single man, or £125 to a man who brings his family. Salary begins upon arrival in South Africa, and no allowance will be made for return traveling expenses. No. 349.-A Canadian university wishes to engage a man to teach non-ferrous metallurgy and ore-dressing as well as to direct research work. The instruction work covers 7 months but the research work is continued throughout the year. To a suitable man the rank of professor will be granted. Applicants are requested to state education, experience, salary desired and any other particulars that might assist in selecting a man for this position. No. 350.-Wanted, 60 engineers for ordnance training school, month's training. Salary for first three months $1200 to $1500. After 3 months, up to $2400.

Jan 11, 1918

[ ] Utilizing tendencies for low grade ores in the Sudbury District of Ontario to cave after higher grade ore has been mined, International Nickel Co., of Canada, Ltd., is recovering millions of tons of nickel-copper ore once regarded as submarginal. Inco is working lower grade ore than ever mined before from its underground operations because of the caving method and metallurgical practices. In the caving method, blocks containing as much as 1.5 million tons of ore are undercut. As ore from the undercut block is withdrawn, the block to be mined breaks away and starts to disintegrate as it moves downward. Inco is also using the blasthole method, using explosives to break slices of harder, tougher ore from solid material. Inco has built a new concentrator at one of its most recent shafts for handling the increased tonnages of low grade ore. The concentrator presently has a 10,000-ton per day capacity, and is scheduled to be increased to 12,000 tons. Hoisting from the mine is by push-button control and the ore is milled on the spot. A 7 ½ -mile pipeline carries bulk concentrate to reduction plants at Copper Cliff. Giant crushers, weighing 165 tons each, have been installed underground. Twenty-ton electric locomotives haul ore to the crushers. The expansion program is expected to lift total annual production of nickel in the free world to 375 million pounds annually, an increase of 150 million pounds. Inco is presently mining more than 1 million tons of ore per month from combined surface and underground operations.

Jan 1, 1952