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By S. C. Sun, T. Chao

The reaction of gaseous sulfur trioxide with different aluminum-bearing minerals for the conversion of their alumina content into water soluble sulfates has been investigated. Theoretical considerations indicate that this reaction is thermodynamically feasible and that preferential sulfatization can be accomplished. The five minerals tested were gibbsite, boehmite, diaspore, kaolinite, and halloysite. In general, over 90% sulfatization could be achieved in 1 hr when using sodium sulfate as an additive at a temperature between 500° and 600°C. It was found that sulfates of the light alkali and alkaline earth metals exhibited some effectiveness in promoting the sulfa-tizing reaction. Selective sulfatization of alumina in a mixture of calcined halloysite and ferric oxide was accomplished. The gas-solid type of sulfatizing reactions have become increasingly important in recent years for the treatment of the oxides of such nonferrous metals as cobalt,' nickel,' manganese,3 zinc, and copper.4-6 Similar reactions were attempted in the present investigation for the recovery of aluminum from the low grade aluminous ores. Unlike the Bayer process in which silica is a serious contaminant, or the acid processes whereby iron usually causes difficulties, the reactions between gaseous sulfur trioxide and various aluminous minerals could hopefully be selective for aluminum. THEORETICAL CONSIDERATIONS Reactions between aluminum-bearing minerals and gaseous sulfur trioxide have been shown respectively in Table I and Fig. 1 to be thermodynamically favorable for temperatures below 1000°K approximately. Calculations of the thermodynamic functions were where ?G, ?H, ?Cp and ?S are changes in free energy, enthalpy, constant-pressure specific heat, and entropy of the system under consideration, respectively; T is the absolute temperature, R the universal gas constant, and K the equilibrium constant. Thermochemical data so far available for these calculations were based on sources given by T. Chao.7 In Table I, the free energy values indicate that reactions between the gaseous sulfur trioxide and

Jan 1, 1968

By Anson G. Betts

A solution of lead-fluosilicate, containing an excess of fluosilicic acid, has been found to work very satisfactorily as an electrolyte for refining lead. It conducts the current well, iseasily handled and stored, non-volatile and stable under electrolysis, may be made to contain a considerable amount of dissolved lead, and is easily prepared from inexpensive materials. It possesses, however, in common with other lead electrolytes, the defect of yielding a deposit of lead lacking in solidity, which grows in crystalline branches toward the anodes, causing short circuits. But if a reducing-action (practically accomplished by the addition of gelatine or glue) be given to the solution, a perfectly solid and dense deposit is obtained, having very nearly the same structure as electrolytically-deposited copper, and a specific gravity of about 11.36—that of cast-lead. Lead-fluosilicate may be crystallized in very soluble, brilliant crystals, resembling those of lead-nitrate and containing four molecules of water of crystallization, with the formula PbSiF,,4H20. This salt dissolves at 150 C. in 28 per cent. of its weight of water, making a sirupy solution of 2.38 sp. gr. Heated to 60° C., it melts in its water of crystallization. A neutral solution of lead-fluosilicate is partially decomposed on heating, with the formation of a basic insoluble salt and free fluosilicic acid, which keeps the rest of the salt in solution. This decomposition ends when the solution contains, perhaps, 2 per cent. of free acid; and the solution may then be evaporated without further decomposition. The solutioi~s desired for refining are not liable to this decomposition, since they contain much more than 2 per cent. of free acid. The electrical conductivity depends mainly on the acidity of the solution. My first experiments were carried out without the addition of gelatine to the fluosilicate solution. The lead-deposit con-

Jan 1, 1904

By E. L. Spain

The deposits described in this paper occur over much of Wayne County and in the southeast portion of Hardin County, Tennessee, and in the northeast and northwest portions of Mississippi and Alabama respectively. The presence of tripoli in this region has been known for some time and descriptions of various occurrences in Tennessee have been made by Jewelll and Miser2, while Hilgard3, Lowe4 and Logan5 have treated the deposits that occur in the adjacent portions of Alabama and Mississippi, but there has not been a 'general survey of the entire field summarizing completely the geology of the deposits with respect to their origin and stratigraphic relationships. During 1934, while engaged in surveys of mineral resources through this region for the Tennessee Valley Authority, the writer collected data with this in mind, and has assembled them in this report. He is indebted to H. S. Rankin and N. A. Rose, of the Tennessee Valley Authority Geology Division, for field assistance. Location of Tripoli Deposits Fig. 1 shows the locations of deposits of tripoli in a long belt that extends from northeast Wayne County southwestward into northwest Alabama and thence passes into Mississippi, where the formations carrying it are finally covered by Cretaceous sand and gravel of the Mississippian Embayment. Occasional deposits occur also in the southeastern corner of Hardin County, Tennessee. While tripoli is found at nearly all points along this axis where the related formations are exposed, the largest deposits are grouped about three different centers. Waynesboro-Collinwood District.—In the area between Waynesboro and Collinwood, in Wayne County, Tennessee, tripoli of various grades outcrops in the valley of Green River and in tributary valleys on either side. This district is roughly 12 miles long in a northeast-southwest direction and has a maximum width of 5 miles at its northern end. Exposures are found in road cuts, highway chert pits, in the beds of some of the streams, and on hillsides. The greatest number of high-grade

Jan 1, 1938

By E. L. Spain

The deposits described in this paper occur over much of Wayne County and in the southeast portion of Hardin County, Tennessee, and in the northeast and northwest portions of Mississippi and Alabama respectively. The presence of tripoli in this region has been known for some time and descriptions of various occurrences in Tennessee have been made by Jewelll and Miser2, while Hilgard3, Lowe4 and Logan5 have treated the deposits that occur in the adjacent portions of Alabama and Mississippi, but there has not been a 'general survey of the entire field summarizing completely the geology of the deposits with respect to their origin and stratigraphic relationships. During 1934, while engaged in surveys of mineral resources through this region for the Tennessee Valley Authority, the writer collected data with this in mind, and has assembled them in this report. He is indebted to H. S. Rankin and N. A. Rose, of the Tennessee Valley Authority Geology Division, for field assistance. Location of Tripoli Deposits Fig. 1 shows the locations of deposits of tripoli in a long belt that extends from northeast Wayne County southwestward into northwest Alabama and thence passes into Mississippi, where the formations carrying it are finally covered by Cretaceous sand and gravel of the Mississippian Embayment. Occasional deposits occur also in the southeastern corner of Hardin County, Tennessee. While tripoli is found at nearly all points along this axis where the related formations are exposed, the largest deposits are grouped about three different centers. Waynesboro-Collinwood District.—In the area between Waynesboro and Collinwood, in Wayne County, Tennessee, tripoli of various grades outcrops in the valley of Green River and in tributary valleys on either side. This district is roughly 12 miles long in a northeast-southwest direction and has a maximum width of 5 miles at its northern end. Exposures are found in road cuts, highway chert pits, in the beds of some of the streams, and on hillsides. The greatest number of high-grade

Jan 1, 1938

By R. G. Baughman

With the constantly increasing sales competition, coal to be sold today must meet the test of quality in every respect. The producers must be able to make all marketable sizes that will meet such general requirements as follows: 1. Ash content must be consistently low, depending upon the use to be made of the coal. 2. Sulfur content must be controlled accurately according to requirements. 3. All sizes must be positively free from visible impurities. 4. Free moisture of washed sizes must be reduced to a minimum. 5. The freezing of wet coal in cars must be prevented. 6. The percentage of fines in small mixed sizes must be controlled to give the uniform and proper combustion when used on various types of automatic stokers. 7. The undersize particles or degradation caused by handling must be kept to an absolute minimum in all sizes loaded. Many difficulties may be met in bringing any particular coal to meet these quality requirements, because the extent to which the quality of a coal may be controlled is determined largely by its physical characteristics. Preparation of an Impure Coal Bed The application of modern and scientific methods in the controlled preparation of bituminous coal from a bed in the mid-western field will illustrate the results that can be accomplished by adequate preparation: The bed referred to contains coal inherently excellent as to low ash and other desirable characteristics; in fact, the coal itself is one of the best in the field. It is, however, divided into four layers by dirt bands of soft shale 1 to 2 in. thick. It also contains much sulfur in the form of sulfur lenses and laminated sheets. Horsebacks or rolls varying from 6 in. to 12 ft. in width are encountered in the mining of the bed and heretofore have rendered it practically unworkable. The mines operating in this

Jan 1, 1931

By C. Everard Arnold

The Giroux Consolidated Mines Co. is equipping a five-compartment shaft at Kimberly, Nev., which will serve the Alpha mine. The depth of this shaft, January, 1910, is 963 ft., and of this depth 948 ft. was opened by raising; 15 ft. of sinking was done so that the bearers, collar-set, and three shaftrsets might be installed and concreted, and with this done it mas possible to erect the necessary surface-equipment for resuming shaft-timbering on the completion of the raise. The arrangement of the shaft-timbering is shown in Fig. 1. At the 1,000-ft. level of the Alpha, and 750 f't. SW. from the Alpha shaft, a 14- by 18-ft. station was cut, and a 25-h-p. airhoist was installed. From here the raising commenced on July 5, 1909. The raise was cut approximately 13 by 21 ft. in area, and supported by timbering with square sets, illustrated in Fig. 2, which shows the division into four compartments. The end compartments, which were used as chutes, had the center girts heavier than in the others on account of the wear from falling rock. The chute-lining was braced by inserting 8- by 8-in. stiffeners parallel to and half way between successive caps. Similarly, the lagging on the wall sides of the cage-way and the compartment for pipes and ladder was stiffened with 4- by 6-in. timbers. In the pipe-and-ladder compartment the chute-stiffeners were reinforced with 8-by 8-in. struts, and as the cage-way was partitioned off by braced lining, there was practically no chance of rock entering the ladder-way in case a chute burst into the cage-way. Over the two center compartments the last two sets were always bulkheaded with 8- by 12-in. timbers, shown in Fig. 3, and from the lower bulkhead the cage sheave-wheel was suspended. After a round of holes had been blasted and the loose

Jan 1, 1911

By Shun-ichi Satoh

In the previous paper, the writer indicated that the arc welding of cast iron is practicable only when barium carbonate is used to retard the fusion of electrodes. Later, he tested the effects of 48 other elements, to discover the cause of their retarding action. Wrought-iron bars 33 cm. long and 0.53 cm. dia. were used as electrodes. The chemical analysis of the original electrode is given in Table 1. Table 1.—Analysis of Electrode Per Cent. Carbon.................................................. 0.045 Silicon................................................... 0.028 Manganese....................................... Trace Phosphorus.............................................. 0.047 Sulfur................................................... 0.008 Each of the bars was wound with a twine of asbestos (1 mm. dia., weighing 0.5 g.) and then was coated with a mixture of equal quantities of graphite and carborundum and one of the compounds listed in the second column of Table 2. The method used in coating was as follows: The mixtures were reduced to paste by adding to them a solution of water glass (1:3); they were next put in a glass tube of 8 mm. inner diameter, with funnel-shaped mouth (the same tube shown in the previous paper); then the bars were passed through the tube so that the mixtures were coated on them. The glass tube was used only as a means of making the diameters of all coated bars exactly 8 millimeters. The cast iron was deposited on the steel plates by connecting the electrodes first to the positive and then to the negative pole of the generator. The figures representing the time, voltage, amperes and energy required to melt each electrode are given in Table 2. They are arranged in the order of the atomic weights of the elements contained in the coatings. In Figs. 1 to 4, which show respectively the time, current, voltage and energy required in this operation, the abscissas indicate the atomic weights of the elements contained in the coatings, and the ordinates

Jan 1, 1929

By Thomas A. Wright

No symposium on die-casting could be complete without consideration of the methods of formula and impurity control. No corisideration of control would be complete without discussion of that new tool of the analytical chemist and inspector, the quartz spectrograph. Just as there is an increased appreciation of the possible applications of the die-casting process and of die castings, so too is there, slowly but surely, of the spectrograph. At present the role of the instrument might well be compared with that of brass or magnesium die castings. Neither is as widely understood or known as they will be. Product specifications are increasing and are getting more explicit and often more rigid. The designer, metallurgist and production engineer or superintendent will be forced to depend more and more on the chemical laboratory. Sampling, as well as analyses, testing and inspection problems will grow. The chemical laboratory must meet its increased responsibility and use of the spectrograph will become more common. Advantages of increased precision, greater speed, lessened labor and often lower costs cannot be ignored. It will be the purpose of this paper in part to outline the respective fields of chemical and spectrographic analyses and to indicate where one may overlap the other and in part to indicate certain possible sources of contamination of zinc-base die-cast alloys in particular. Composition Aluminum.-Aluminum die die castings are expected to conform to the specifications of the Amcrican Society for Testing Materialslt and the Society of Automotive Engineers2. The A.S.T.M. has recognized seven aluminum alloys in Tentative Specification B85-33-T. TWO are straight silicon and the remainder are of the copper-silicon type of which alloys VIII and IX have in addition respectively 2 and 4 per cent of nickel, but unlike the others are not covered by S.A.E. as well. All seven call for rigid control of certain impurities. With the exception of alloy XII,

Jan 1, 1935

By Alexander L. Holley

The 400-ton testing machine, ordered in June, 1875, by the United States Board appointed to test "iron, steel, and other metals," has lately been completed at the Watertown Arsenal, thoroughly proved and accepted by the Board. The excellence of the machine in every respect is more than satisfactory, and its accuracy is at first sight astonishing, although an investigation of its principles must show that if the weighing apparatus will weigh at all, it must do so with perfect accuracy, because all its movements are absolutely without friction. The proof experiments were numerous, and the effects of recoil after sudden ruptures at maximum loads, were watched with great care, but without much anxiety, because the weighing parts affected are by no means delicate in structure, and their motion is almost infinitely small. Among the tests were the following : A forged link of hard, wrought iron, 5 inches in diameter between the eyes, was slowly strained in tension, and broke short off with a loud report at 722,800 pounds. The diameter before breaking at the point of fracture was 5.04 inches; after breaking, 4.98 inches. In order to see if the weighing parts had been disturbed by the recoil, which was obviously near the greatest recoil the machine will ever suffer, a horse-hair was next tested; it was 7-1000ths of an inch in diameter; it stretched 30 per cent., and broke at 1 pound. Other horse-hairs vary in tenacity between 1 and 2 pounds. Of course, the accuracy of the machine on such delicate specimens, and indeed on specimens having some hundreds of pounds tenacity, has been checked and proved by other weighing machines. A 5-inch round bar, turned down to 38 inches diameter along the centre, was pulled apart at 430,200 pounds tension. Then some more horse-hairs were tested ; also copper wires 191/2-1000ths of an inch in diameter, which averaged 25 pounds tenacity..

Jan 1, 1879

By Thomas A. Wright

No symposium on die-casting could be complete without consideration of the methods of formula and impurity control. No corisideration of control would be complete without discussion of that new tool of the analytical chemist and inspector, the quartz spectrograph. Just as there is an increased appreciation of the possible applications of the die-casting process and of die castings, so too is there, slowly but surely, of the spectrograph. At present the role of the instrument might well be compared with that of brass or magnesium die castings. Neither is as widely understood or known as they will be. Product specifications are increasing and are getting more explicit and often more rigid. The designer, metallurgist and production engineer or superintendent will be forced to depend more and more on the chemical laboratory. Sampling, as well as analyses, testing and inspection problems will grow. The chemical laboratory must meet its increased responsibility and use of the spectrograph will become more common. Advantages of increased precision, greater speed, lessened labor and often lower costs cannot be ignored. It will be the purpose of this paper in part to outline the respective fields of chemical and spectrographic analyses and to indicate where one may overlap the other and in part to indicate certain possible sources of contamination of zinc-base die-cast alloys in particular. Composition Aluminum.-Aluminum die die castings are expected to conform to the specifications of the Amcrican Society for Testing Materialslt and the Society of Automotive Engineers2. The A.S.T.M. has recognized seven aluminum alloys in Tentative Specification B85-33-T. TWO are straight silicon and the remainder are of the copper-silicon type of which alloys VIII and IX have in addition respectively 2 and 4 per cent of nickel, but unlike the others are not covered by S.A.E. as well. All seven call for rigid control of certain impurities. With the exception of alloy XII,

Jan 1, 1935

By I. N. Knapp

Introduction.-The special object of these notes is to describe the mixing, testing, and use of mud-ladened water for rotary drilling in such a way as to make them helpful to the driller, the operator, or the engineer in solving his own special drilling problems. The structures, apparatus and tools used are indicated in a general way. No attempt is made to describe the art of rotary drilling; only such description as are necessary to make plain the use of mud are given. The information is the result of actual experience in drilling in Coastal Plain formations. The materials encountered in the wells drilled were unconsolidated sands, gravels, and clays, in which thin layers of sandstones, shell conglomerates, and shales began to appear at about 1,200 ft. in depth, although one well was drilled to 3,018 ft. without encountering any cemented or indurated materials. Unusual Conditions.-The general surface of the ground where the drilling was done being hardly a foot above mean tide, and the daily tidal variation being about 15 in., it was found necessary to plank over the sod surface with 3-in. plank to work from. A 30 by 30 ft. planked area was sufficient to carry the derrick with equipment and 2,500 ft. of 4-in. drill pipe stacked in it. The derrick was set up 3 ft. on cribbed blocking arranged to spread the load over the planking. The engine, boilers, and pipe yard were also carried on 3-in. planking. Drilling Outfit.-This consisted of a derrick, 20 by 20 ft. and 84 ft. high, two 35 h.p., "oil country" boilers, one double 8 ¼ by 10 in. reversible engine, two 10 by 6 by 12 in. duplex mud pumps, one 15-in. rotary, "hoisting works" with chain drive, hoisting block with line, crown block with pulleys, rotary' jetting swivels, hose, complement of tools, pipes and connections, and. a mud mixer, with engine.

Jan 12, 1914

By Morris Cohen

WITHIN the past two years, a number of publications have called attention to the double peaks, or stages, that appear in the hardness and strength curves of certain aging alloys. The author has shown the existence of double hardness peaks during the aging of a high-purity silver-copper alloy;1 and on the basis of electrical resistance, microscopic, dilation and lattice-parameter measurements, he concluded that the initial hardness peak occurs prior to precipitation while the secondary hardening is due to precipitation. It was suggested that the general mechanism of age-hardening involves two consecutive processes, the first consisting of nucleus or knot2 formation, and the second consisting of actual precipitation and particle growth. It was further held that the two stages are interdependent, but because of nonuniform precipitation they may overlap each other to an extent that increases as the aging temperature is raised. At high aging temperatures, the effect of the first stage cannot be detected because of the rapid occurrence of precipitation. The general theory of age-hardening recently presented by Dr. M. L. V. Gayler3 is in close agreement with the picture outlined above. With reference to work done on duralumin, copper-beryllium and copper-silver alloys, Dr. Gayler also concluded that age-hardening takes place in two consecutive steps: first, diffusion (in which the solute atoms migrate to certain crystallographic planes), and then precipitation. However, W. L. Fink and D. W. Smith4 have shown that the double aging peaks that appear in the strength curves of high-purity aluminum-copper alloys may be explained without recourse to pre-precipitation phenomena. By means of very careful metallographic technique, Fink and Smith demonstrated that during aging the precipitation takes place at an accelerated rate along the grain boundaries and slip planes as a result of the plastic deformation caused by the drastic quench from the solution heat-treatment temperature. ? The general precipitation occurs at a

Jan 1, 1938

By J. L. Brimhall, R. A. Huggins

The structure of deformed internally oxidized alloys of siluer- cotztcrining magnesium and copper-containing aluminum in was studied by thin-film transrrzissiotz electron microscopy. With low to moderate amounts of stvain, the deformation structure in t11e dispersion-hardened alloys was found to consist of a high density of dislocations arranged it a random distribution or in a very fine, but poorly defined, cell stucture, depending on the fitness of the dbsbersion and amount of deformation. 112 contrarst, both pure copper and silver show relative1y Large, distinct cell structures. The particular structures in the alloys are believed to result from particles acting as both dislocaliot~ sources and deflector-s. The Inck of a pvorzolrr~ced deformation texture tr~ regiotzs qf' seoere loctll plastic curvature after heavy deformation can also be traced to the formation of clislocntions on many slip systemes and a lack 01 local concentrations of dislocations of predominantly one sign. THE presence of fine dispersions of a second phase has long been known to have a strong influence upon the mechanical properties of solids. Until recently, the influence of particles on the deformation mechanisms has been assumed to be solely that of barriers to dislocations. This is seen in the classic models of edge dislocations being restrained by the particles.1 4 There is, however, considerable evidence that this is not their primary effect, and that the particles can have a large influence on the defect structure generated by plastic deformation. The presence of particles causes changes in the surface topography observed after deformation. In overaged precipitation-hardened materials containing hard, noncoherent precipitates, fine intersecting slip lines are found after deformation of single crystals. indicating the activation of many slip systems. This has been extensively observed in the A1-Cu systen;, both by optical microscopy and replica electron microscopy.'"13 In some of the observations. the slip lines were seen to extend between the particles. Similar observations of extremely fine slip lines or the apparent absence of normal slip lines have also been found in A~-M~."

Jan 1, 1965

By S. H. Ash

Mass production methods, although increasingly important for economic reasons, create new hazards, remove many hazards, and improve health and safety by reducing exposure and obtaining better supervision. Such methods must be efficient or be discarded. Skilled workmen are required who must be trained to utilize equipment that replaces picks, shovels, and explosives. The effects of working conditions on the health of workmen have long been evaluated in noncoal mines. Studies and action programs relating to environmental health hazards in the mineral industry have placed particular emphasis on dusts. The anthracite industry is conducting an action program on the problem of dust. Segments of the bituminous industry are now conducting similar investigations. An industrial hygiene survey of coal mining in the State of Washington has been conducted and the results published in 1949. (State of Washington, Department of Health, I. H. Bul letin 4.) Chest X rays were obtained from miners in the six major coal-producing counties. State Health Department mobile X-ray equipment was set up at most large mines. Participation was on a voluntary basis, and response was obtained from 70 percent. Important in successful mining safety programs are training programs for supervisors and workmen alike. These programs recognize that the employe is the focal point in injury prevention and are planned and function around him. During the war, industries had to compete with each other for workers and to obtain and hold good workers, working conditions had to be made attractive. The average age of the mine worker increased, and, contrary to what many expected, mining injury rates decreased rather than increased. To attract competent workers, risks to life and limb, as well as laborious tasks, have to be reduced, and an experienced worker is indispensable for safety. Young men are returning to modernized mines. Mass production methods and equipment are more to their liking; jobs are more remunerative, demand action, and require special training and skill that give them the mark of a craftsman. Such workmen can be taught safe methods.

Jan 1, 1950

By Lyndon L. Foley

The proper spacing of oil wells is a problem of vital importance to the oil industry. Conservation demands a maximum recovery, while economic considerations attach primary importance to profitable extraction of oil. Formulas have been evolved,1-4 which attempt to solve the spacing problem mathematically, using reservoir characteristics as factors. Comparisons have been made of fields producing from supposedly similar sands, which have been drilled to varying densitiesl5,6 and also of different leases in the same field. 5-8 Intermediate wells have been drilled in old, depleted fields to test the efficiency of drainage by the original operation.9-11 Intermediate wells have been drilled also to obtain cores of the depleted sand for analysis, from which to learn the degree of efficiency of extraction. The problem is being attacked by many students, and along several different lines. Unfortunately, the fields now depleted were produced generally without restriction, and conclusions drawn from them may not apply to fields operated under restricted production. Reservoir conditions in a restricted field, especially reservoir pressures and pressure gradients within the reservoir, are quite different from those in a field produced to capacity. Many people have held the idea that the closer the spacing, the greater the recovery. This general statement is not always true, as other factors than well spacing enter into the recovery problem. Cutler,5 who has been quoted frequently by advocates of close spacing, limited his conclusions to gas-drive fields, and to the particular fields and spac-ings that he investigated. Hill and Sutton7 analyzed four tracts in the Powell field; the tract most closely drilled had the third largest recovery per acre-foot, and the tract with the widest spacing had the second largest recovery per acre-foot. A search of the references to well spacing in the publications of the U. S. Bureau of Mines5,13-19 discloses repeated condemnations of the wastefulness of the practice of town-lot drilling.

Jan 1, 1938

By Alexander L. Holley

THE 400-ton testing machine, ordered in June, 1875, by the United States Board appointed to test "iron, steel, and other metals," has lately been completed at the Watertown Arsenal, thoroughly proved and accepted by the Board. The excellence of the machine in every respect is more than satisfactory, and its accuracy is at first sight astonishing, although an investigation of its principles must show that if the weighing apparatus will weigh at all, it must do so with perfect accuracy, because all its movements are absolutely without friction. The proof experiments were numerous, and the effects of recoil after sudden ruptures at maximum loads, were watched with great care, but without much anxiety, because the weighing parts affected are by no means delicate in structure, and their motion is almost infinitely small. Among the tests were the following : A forged link of hard, wrought iron, 5 inches in diameter between the eyes, was slowly strained in tension, and broke short off with a loud report at 722,800 pounds. The diameter before breaking at the point of fracture was 5.04 inches; after breaking, 4.98 inches. In order to see if the weighing parts had been disturbed by the recoil, which was obviously near the greatest recoil the machine will ever suffer, a horse-hair was next tested ; it was 7-1000ths of an inch in diameter; it stretched 30 per cent., and broke at 1 pound. Other horse-hairs vary in tenacity between 1 and 2 pounds. Of course, the accuracy of the machine on such delicate specimens, and indeed on specimens having some hundreds of pounds tenacity, has been checked and proved by other weighing machines. A 5-inch round bar, turned down to 3 5/8 inches diameter along the centre, was pulled apart at 430,200 pounds tension. Then some more horse-hairs were tested ; also copper wires 19 1/2-1000ths of an inch in diameter, which averaged 25 pounds tenacity..

Jan 1, 1879

By R. E. Reed-Hill, J. L. Martin

Kinking is an important deformation phenomenon in poly crystalline a zirconium. The crjlstallo-gvaphic features of the most important form of kinking have been determined with the aid of twins formed at 77°K in grains previously kinked at high temperatures. It has been .found that the kink-band boundaries correspond to walls of edge dislocations with (1150) Burgers vectors and dislocation lines parallel to (1070). The present observations imply that basal slip is an important secondary-slip mode in polycrystalline zirconium. Previous single-crystal studies13 did not veveal this mode Other evidelzc.e for (0002)(1120) slip is also presented. ThE first studies of kinking in hexagonal metals were made by orowan,1 using single-crystal cadmium wires. He suggested that this was a new de- formation mode in metals, different from ordinary glide or twinning. Next, Hess and Barrett2 studied zinc-crystal rods in compression, and were able to offer an explanation of the phenomenon described by Orowan. They concluded that kinks required no new deformation mechanism and were a special form of deformation band that developed gradually and solely from basal glide. Similar kink bands were then observed by Washburn and parker3 on zinc crystals deformed in tension at low stresses and high temperatures. In titaniun,4 kink bands associated with {1010}<1120> prism slip have been observed in coarse-grained specimens. Magnesium5 and rhenium6 have also been observed to kink in conjunction with their basal- and {1010} prism-slip systems, respectively. Yttrium has (1010) as a predominant slip plane, but no observations of kink bands were reported.7 Since no previous investigations of kink bands in zirconium have apparently been made, this study was proposed. Its aim was to determine the crys-tallographic features of a type of kink band frequently observed in polycrystalline zirconium. EXPERIMENTAL APPARATUS All tests were performed on a type TTC Instron machine. The cross-head speed usually chosen in tension or compression was 0.02 in. per min. Ten-

Jan 1, 1964

By R. V. Lukes, H. W. Scheeline

Knowledge of a large number of the physical properties of the hydrocarbons is needed in the calculations and studies of the production engineer. Since experimental data on these properties of the individual hydrocarbons and their mixtures are available in only a relatively few cases, the use of generalized correlations has developed rapidly in the last decade. The generalized correlations of pressure, volume and temperature,&apos; enthalpy2 and vapor-liquid equilibria13 on the basis of reduced temperatures and pressures, are outstanding examples of this development. These correlations are of particular value to the production engineer interested in the flow of oil and gas, since they can be used to estimate the conditions under which segregation of phase occurs as well as the composition, density, and relative amounts of the phases. The technique of using the correlations for such estimations has been published by several authors4 and will not be considered in this paper. A considerable number of data have been obtained to check the generalized pressure-volume-temperature correlations, and these data indicate that such relations hold for the hydrocarbons from methane to heptane. The accuracy is in general sufficient for most engineering pressure-volume-temperature calculations. However, the generalized correlations of enthalpy and vapor-liquid equilibria have in general been developed from the pressure-volume-temperature correlations by thermodynamic calculations and only a relatively few experimental data are available to check these calculated values. The calculations from pressure, volume and temperature are likely to lead to large errors in the calculated enthalpy and vapor-liquid equilibria. Thus, in the calculations of enthalpies, slopes of the pressure-volume-temperature data are employed, and determining these slopes can greatly amplify small errors in the original data. In the vapor-liquid equilibria calculations it is necessary to have the pressure-volume-temperature relations of the mixture, and the latter propertics are much more questionable than those of pure components, particularly in the critical region. A considerable number of experimental data are

Jan 1, 1939

By R. V. Lukes, H. W. Scheeline

Knowledge of a large number of the physical properties of the hydrocarbons is needed in the calculations and studies of the production engineer. Since experimental data on these properties of the individual hydrocarbons and their mixtures are available in only a relatively few cases, the use of generalized correlations has developed rapidly in the last decade. The generalized correlations of pressure, volume and temperature,&apos; enthalpy2 and vapor-liquid equilibria13 on the basis of reduced temperatures and pressures, are outstanding examples of this development. These correlations are of particular value to the production engineer interested in the flow of oil and gas, since they can be used to estimate the conditions under which segregation of phase occurs as well as the composition, density, and relative amounts of the phases. The technique of using the correlations for such estimations has been published by several authors4 and will not be considered in this paper. A considerable number of data have been obtained to check the generalized pressure-volume-temperature correlations, and these data indicate that such relations hold for the hydrocarbons from methane to heptane. The accuracy is in general sufficient for most engineering pressure-volume-temperature calculations. However, the generalized correlations of enthalpy and vapor-liquid equilibria have in general been developed from the pressure-volume-temperature correlations by thermodynamic calculations and only a relatively few experimental data are available to check these calculated values. The calculations from pressure, volume and temperature are likely to lead to large errors in the calculated enthalpy and vapor-liquid equilibria. Thus, in the calculations of enthalpies, slopes of the pressure-volume-temperature data are employed, and determining these slopes can greatly amplify small errors in the original data. In the vapor-liquid equilibria calculations it is necessary to have the pressure-volume-temperature relations of the mixture, and the latter propertics are much more questionable than those of pure components, particularly in the critical region. A considerable number of experimental data are

Jan 1, 1939

By Frank Firmstone

IN the summer of 1881 we were forced to break up and remove the large mass of iron which had accumulated under No. 2 furnace at Glendon, in order to prepare the foundations of the new furnace which has taken its place. We used "Atlas" powder, drilling the holes with a pair of Rand drills. These worked very well when the iron was at all uniform in hardness; but this was not often the case; and it frequently happened that the holes were hopelessly blocked when but little over a foot deep. Good tamping became, therefore very important. The common method of tamping is certainly very dangerous when there is a percussion cap in the hole, and has, no doubt, caused many of the accidents attributed directly to high explosives. We found an excellent and safe method by using plaster of Paris, mixed to the proper consistency and ponred into the holes as soon as they were loaded. Clean dry sand was mixed with the plaster to reduce the quantity needed. With proper attention the tamping would set in a few minutes, and little or no more time was required than for tamping in the ordinary way. We used a "magneto" machine (Laflin and Rand) to fire the holes; and an additiollal advantage in the plan was that any risk of cutting the exploder-wires in tamping was avoided. We found it worth while to load holes not over 13 inches deep in a block 3 or 4 feet thick since the bottom of the hole was enlarged by each shot so that the next time it could be loaded more heavily, and three or four shots in this way often did as much good as a new hole twice the depth, to drill which might have taken ten or twelve hours. The rise in temperature when boiled plaster solidifies is not sufficient to ignite the exploders, as we found by repeated trials before using it in a loaded hole.

Jan 1, 1884