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By AIME AIME

ALL 32 of the Local Sections of the Institute in the continental United States and practically all of the Divisions as well, had representatives present at the Conferences of Local Section and Division Delegates at the Annual Meeting. Three sessions were held, two on Monday and one on Thursday, both the incoming and outgoing Presidents of the Institute being on hand to con- duct the meetings. H. J. Brown was called to the chair during a portion of the last session, President Fulton having to leave early. Complete minutes of the meetings have ,been sent to all delegates. In general, the Local Sections appeared, from their reports, to have risen to the wartime demands made upon them with their usual resourcefulness. Apparently more difficulty has arisen in the last year in arranging attractive programs and securing acceptable speakers, this being perhaps attributable to the fact that most technical men have been extremely busy. Careful planning ahead .has usually brought good results, however. Another wartime difficulty has been the matter of transportation to meetings, gasoline rationing and congestion on the railroads and buses being a handicap to attendance. Sharing cars has proved practical as a method of meeting this issue, this again requiring planning. Suitable meeting places and a supply of food have been another difficulty for some local groups.

Jan 1, 1944

By Mara Kosovac, Sujan K. Kundu

The Iron Ore Co. of Canada (IOC) has developed a computerized plan analysis method for its open-pit iron mining operations which will eliminate much of the tedious manual drafting of pit design plans performed by engineers and geologists at its two major operational areas near Schefferville, Que., and Labrador City, Nfld. The new technique permits analysis of section or bench plans for a specific ore body, based on drillhole information; preparation of a three-dimensional unit profit matrix for pit design purposes, and storage of extensive ore-block information for other applications. Other advantages include enhanced design accuracy through reduction of human errors normally associated with preparation of large data masses, and by elimination of errors inherent in planimeter-prepared ore block diagrams.

Jan 7, 1978

News has just been received that Flight Commander William T. Hall, a Junior Member of-the Institute, was killed in action on Saturday, May 19, 1917. According to the' Toronto Star, Commander Hall was 24 years of age, a native of Toronto, and a grandson of the late William Kersteman. During the four years of his course in mining at the School of Practical Science, Toronto University, he passed every examination with honors. When war was first declared Commander Hall endeavored to join the artillery as an officer, and for that purpose secured a provisional lieu- tenancy with a Hamilton battery, but he did not receive an overseas appointment, and on being graduated as a mining engineer in 1915, he was offered a position in Chile, which he accepted. He left Toronto on May 27, 1915, and was engaged in Chile as a mining engineer for nearly a year. In the latter part of April, 1916, he decided to offer himself again for service at the front. He crossed the Andes and sailed for Liverpool, where he landed on May 13, 1916. On May 27, 1916, Capt. Hall was given a commission as lieutenant in the Royal Flying Corps. He went to the front on Sept. 1, 1916, and remained there continuously. On April 4, 1917, he was promoted from lieutenant to the rank of flight commander. No details of how Commander Hall came by his death have as yet been received.

Jan 1, 1918

By C. Feng, C. Elbaum

AN investigation of the fracture plane of titanium, containing 0.5 wt pct to 1 wt pct 0, was recently carried out by fracturing large-grain specimens in a tensile jig at room and liquid air temperature. The experiments were carried out on strip specimens 3 to 5 mm wide, 2 mm thick and about 100 mm long. The specimens consisted of several grains, each occupying the entire cross section of the strip and extending over a length varying from 5 to 20 mm. These specimens were prepared by a method described elsewhere.' The identification of the fracture plane was possible in twelve of approximately thirty crystals investigated. In some cases severe local distortion took place near the fracture and prevented identification of the fracture plane. On, at least, three occasions the fracture propagated in a helicoidal

Jan 1, 1959

By P. T. Chiang

Chemical etching methods for the simultaneous revealing of the tellurium or selenium Phase and the chalcogenide grain boundaries of the alloy systems are given. A tellurium eutectic was found Present in zone-melted ingots. Similarly, a selenium monotectic was present in ingots. In general, the second phase (tellurium or seleniumn) occubies three different sites; viz., along the chalcogenide grain boundaries, as inclusions within the chalcogenide grain, and on the undersurface of the ingot. The detection limit for the tellurium phase is about 1 u in width. THERMOELECTRIC materials based on Group V (bismuth, antimony) and Group VI (selenium, tellurium) elements have aroused considerable interest in recent years in the practical application of thermoelectric cooling. In many cases, a small amount of excess tellurium (or selenium) was added to the material to optimize its thermoelectric properties. Then the question immediately arises as to the number of phases present in the resultant alloy. In the binary systems of Bi-Te, Sb-Te, and Bi-Se, the congruent melting compositions have been reported to be non-stoichiometric and are represented by Bi~Te respectively. It is to beexpected and known that Bi2Te3 and SbzTe3 crystallize from the melt with an excess of bismuth and antimony in the lattice and that tellurium forms a eutectic.~' The same could be assumed to take place in the pseudo binary systems of (Bi,Sb)zTe3 and Bi2(Se,Te)3 as well as in the system studiedby puotinen5 and other workers. Likewise, BiaSe3 crystallizes from the melt with an excess of bismuth in the lattice and selenium forms a monotectic.~ Therefore, in practice, alloys solidified from the melt often contain a second phase (tellurium or selenium) in one region or another of the solid mass even without the addition of excess tellurium (or selenium). ~u~~recht' studied the thermoelectric properties of (Bi,Sb)2Te3 alloys with excess tellurium and simultaneous additions of selenium. He mentioned that the materials show two phases because of the considerable excess of tellurium or selenium. However, he did not report as to how the tellurium or selenium phase was identified. It is generally believed that the presence of an excessive amount of tellurium or selenium phase in the alloy would adversely affect its thermoelectric properties and its uniformity. Consequently, there is a need for a simple method for the identification of the tellurium and selenium phase. The quantity of the second phase present is usually too small to be detected either by chemical analysis or by normal X-ray techniques. This investigation was therefore carried out, first, to devise a simple metallographic method for the identification of the tellurium or selenium phase coexisting with the chalcogenides and, second, to determine the distribution and specific location of the tellurium or selenium phase in the ingots. EXPERIMENTAL PROCEDURE The starting materials used for the alloy preparations were 99.999 pct pure bismuth, antimony, and tellurium and 99.997 pct pure selenium. The bismuth and antimony were obtained from Consolidated Mining and Smelting Co. of Canada Ltd., while the selenium and tellurium were obtained from Canadian Copper Refiners Ltd. The tellurium was purified further in the laboratory by zone refining. The elements were pulverized in a stainless-steel pestle and mortar. The amounts for the desired composition were weighed out each time on an analytical balance to make up a 100-g sample. Then the sample was introduced into a Vycor ampule (19 by 150 mm), pumped down to a vacuum of 10"5 Torr for 15 min, and sealed off. The ampule was then heated in a horizontal resistance furnace at 800" to 900°C for about 20 hr. During this period the assembly was rocked back and forth several times to ensure good mixing. At the end of the heating period, the ampule was quenched in cold water and then transferred to the zone-melting apparatus described in a previous publications to grow large-size aligned polycrystals. The background and ring-heater temperatures were adjusted to make the freezing solid-liquid interface slightly convex to the liquid. The recorded temperature gradient in the vicinity of the freezing solid-liquid interface was around 15°C per cm. The ampule was moved horizontally at a speed varying from 0.4 to 2 cm per hr so that the ring heater would cover the whole ingot length from end to end. A single zone-melting pass was used for the Bi-Te, Sb-Te, and Bi-Sb-Te ingots. Two passes in the forward and reverse directions were carried out for the Bi-Se and Bi-Se-Te ingots. Six passes in the forward and reverse directions were performed for the Bi-Sb-Se-Te ingot. The zone-melted ingots were found to contain several large crystals, with their basal planes (0001) approximately parallel to the growth axis. Samples of bismuth and antimony tellurides coated with a layer of tellurium, and bismuth selenide coated with a layer of selenium, were prepared for comparison in phase identification. These coatings were made by dropping a piece of the zone-melted ingot into some molten tellurium or selenium under argon atmosphere and allowing them to cool slowly to room temperature. The metallographic specimens were prepared by

Jan 1, 1969

By L. C. Armstrong

Twice in the past two years and in two widely separated localities—ane near Williamsville, Mo., and the other in the Allard Lake district of Quebec— the Contract Drilling Division of the Longyear Company has experienced perplexing difficulties in drilling granitoid igneous rocks. The rocks in both places are characterized by appreciable amounts of feldspar intimately inter-grown with quartz particles of microscopic dimensions. The disappointingly slow rate of advance and the exceptionally high bortz loss, obtaining during the life of these two projects, are ascribed largely to the resistance to abrasion of these two minerals when arranged in this intergrown pattern. Whether all intergrowth-bearing igneous rocks would offer extraordinary resistance to bit progress cannot be stated with assurance on the strength of these experiences alone. More data on diamond drilling this sort of material in a number of localities are needed before any generalizations can be made safely. It should be pointed out that the lack of time and funds made it impossible for the writer, or other persons interested in correlating the details of bit histories with the kinds of rocks drilled, to be present during the performance of the contracts. However, the records kept in the normal course of drilling are deemed complete enough to be reportworthy. This information is presented here together with the findings made in studies of the rocks involved, with the thought that it may attract the comments of others who may have encountered similar refractory drilling conditions. A pooling of knowledge on the problem would be of material aid in devising more efficient cutting tools and procedures for penetrating this kind of rock. Drilling Blastholes in the Williamsville Granite Due to the unsatisfactory perform- ance of pneumatic percussion drills in boring blastholes on a construction contract near Williamsville, Mo., tests were made with a diamond drill. The poor progress achieved and the excessive loss of diamonds, however, soon led to the abandonment of these trials. The diamonds, in all of the bits tried, lost their cutting edges and acquired a polish after being in service for distances ranging from a few inches to a few feet. Coring bits containing surface-set, whole-stone bortz in a tungsten powder matrix were employed. The cost assignable to bortz wear averaged $7.17 per foot. This item of expense is several times the amount normally expended in diamond drilling in firm, unfractured, granitic rocks. Diamond-impregnated, tungsten carbide bits also were used without success. The diamond wear was at the rate of $0.98 per foot, but the diamond chips became too polished for further duty in less than a foot of drilling. The Williamsville granite is pink and medium-grained. In the hand specimen, it has a fresh, sound appearance; it is seemingly composed almost entirely of interlocking grains of feldspar and quartz and has no discernible features suggesting a greater durability than is usually found in rocks with this composition and texture. Microscopic examination, however, reveals a predominance of feldspar grains with more or less regularly distributed and sharply angular masses of quartz (see Fig 1). The pattern assumed by the two minerals in this mode of occurrence is referred to as a "graphic intergrowth," as it bears some resemblance to the cuneiform characters of ancient Persian writing. The other principal constituents are quartz-free feldspars (microcline and orthoclase) and quartz. All of these constituents are in nearly equidimensional grains, ranging up to about 3 mm in length. There are also

Jan 1, 1950

By J. B. Urnfileb

THE function of gas in the development and production of oil has far reaching consequences that should be emphasized. The technical aspects of the subject have recently had a great deal of attention but less thought has been given to fundamental concepts underlying oil and gas law and the many customs and practices that have grown up in the industry. I shall re- view briefly the advance in knowledge of the subject and attempt to relate these concepts to legislative, judicial and operating problems. Early writers on oil and gas in Pennsylvania noted their close association in oil pools and their contemporaneous decline in output; also, that as gas pressure decreases so does production, that new offset wells reduce the output of existing wells, and even that tubing a well lengthens its flowing life. Expanding gas was deduced as the principal expulsive force. These fundamental observations had been made at least as early as 1880.l They were treated, however, as academic considerations and did not greatly influence law or practice for many years except to instil into all operators an urgent desire to hasten offset drilling to obtain as much of the flush as possible.

Jan 1, 1932

By T. Toda, R. Maddin

A study has been made of the microstructure and mechanical properties of splat-cooled aluminum-base gold alloys with gold concentration from 0.25 to 5.0 wt pct. These alloys have been quenched from the liquid state by a torsion-catapult technique, which has made it possible to pepare specimens suitable for mechanical property measwements. From the electron micrographs it has been shown that the solid solubility of gold in aluminum can be extended to 2.5 wt pct (0.35 at. pct) by splat-cooling, while the maximum equilibrium solubility is known to be less than 0.3 wt pct (0.04 at. pct). The very fine grain size (several tenths of a micron), the extended solid solubility, and the fine dispersion of a second phase (AuAl2) contribute concurrently to a substantial strengthening effect. In Al-5 wt pct Au splat-cooled specimens of less than 50 thickness, the yield strength is 17 kg per sq mm or 6 times as large as the strength of bulk specimens. For the Al-1.0 to 2.5 wt pct Au solid solution obtained by splat-cooling, the yield strength reaches 7.5 kg per sq mm after an aging treatment (for 10 hr at 200°C), while it is 3.7 kg per sq mm for the corresponding bulk specimens. A great deal of research has been done in recent years on the structure and the properties of metals and alloys rapidly quenched from the liquid state.' The term "splat-cool" has been used with the meaning of a rapid quenching from the liquid state., The splat-cooling techniques have produced large numbers of new structures, which are expressed in terms of metastable phases,3 concentrated solid solutions,4 amorphous phases,5'6 new phases,7 and so forth. Nearly all previous studies have concentrated on the physical properties; i.e., crystallography, structure, electrical resistivity, magnetism, and so forth, of the splat-cooled metals and alloys. The mechanical strength of splat-cooled metals and alloys has hardly been investigated except for some recent work by MOSS' on A1-V alloys. The principle common to all experimental techniques developed to obtain very rapid quenching rates is based on the heat transfer by conduction. Liquid must be in good thermal contact with a substrate of high heat conductivity. Both of the published devices known as the "gun" and the "piston and anvil" techniques suffer from certain shortcomings. For example, the specimen obtained by the gun technique is very small and flaky, and hence inadequate for mechanical properties measurements. On the other hand if the material is forced to yield a continuous speci- men by the piston and anvil technique, it is probable that some plastic deformation occurs during the quench. A novel method for rapid quenching of a liquid metal or alloy, the "torsion-catapult", has been devised by Roberge and Herman9 at the University of Pennsylvania. In the apparatus the melt is thrown out of a curved furnace by a catapult and impinges on a copper substrate. The apparatus has the advantage of producing a continuous foil which is relatively large in size and of a quality suitable for the measurements of mechanical properties. The quenching rate is estimated to be of the order of l05 to l06 ºC per sec, (comparable to rates achieved by the piston and anvil technique). In selecting an alloy to be studied we were made aware of the fact that gold was believed to be "insoluble" in in and consequently age hardening in the A1-Au system appeared to be interesting. Quite recently Heirnendahl13-15 revealed that the solid solubility, as determined by transmission electron microscopy, was 0.3 wt pct Au at 640°C and 0.25 wt pct Au at 600°C, decreasing with decreasing temperature. In an A1-0.2 pct Au alloy after quenching from a solution treating temperature of 600°C the yield stress was 2 kg per sq mm, and it increased up to 6 kg per sq mm after aging for 1 to 10 hr at 200°C. The precipitation occurred in the form of platelike particles mainly on (100) matrix planes. The intermediate phase n', the equilibrium phase n (AuAl2), and lattice relationships between both precipitates and the matrix were also investigated by electron microscopy. One of the purposes of the present research is to determine whether or not the solid solubility in this system, in which gold has a very small solubility in

Jan 1, 1970

By R. B. Newcombe

Despite abnormal economic conditions and the unhealthy state of the petroleum industry, 1930 closed without any marked decline in total production of oil in the Middle Western States. The most accurate figures available would indicate for this district an output of close to 25,000,000 bbl. for 1930 as compared to 26,000,000 bbl. for 1929. This can be accounted for by the settled nature of a great many of the wells producing in this area and the favorable geographical position, which affords adequate refining and marketing facilities. The only new flush production field discovered in the area was the Legrande oil pool in southeastern Hart County in western Kentucky, where wells up to 1000 bbl. initial have been reported from a shallow depth. Important extensions have been found in a number of central Ohio fields, and activity in the central Michigan area resulted in new pools along the northwest trend of the Mt. Pleasant structure. These new districts, known as the Leaton and Vernon pools, have not yet reached the scope of the Mt. Pleasant field proper, and although the structure is similar, sand conditions are not strictly analogous. Wildcatting was retarded somewhat by the scarcity of market for oil and many important wells were shut down for several months. This has not shown such a profound effect on production as the reticence of operators to drill inside proven locations. The major companies have not been able to dispose of their oil and the smaller operating units are having trouble financing their projects. The result is that oil in sight is not being produced and output is suffering accordingly. Another important effect on production was the introduction of proration by the major crude purchasers and a voluntary shut-down by Kentucky operators. This step became necessary because of the glutting of lake port refineries with Mid-Continent oil, and was not fostered by regulating state bodies, as in the case of the southwestern states. Small refining units have sprung up to meet this situation in a number of instances but they have experienced some difficulty in disposing of their product because of "dumping" tactics from other quarters. New refinery outlets on the Great Lakes and new pipe line connections should tend to alleviate this difficulty during the coming year. The

Jan 1, 1931

By Charles A. Morgan

The proms of mire drawing depends upon the property which certain metals possess, termed ductility, which is defined in Brande's Dictionary of Science as a property inconhequcnce of which metals may be drawn out at length wilhotit interrupting the continuity of their constituent parts. As ticfincd thy M. Tresca, it is the property of flowing when subjected to pressure, and ie termed by him the "flow of solids," in his paper, read before the AcaiXemy of Sciences in Paris, November, 1866 * In the simple language of the wire shop, it is that quality in certain metals that thcm to be drawn (or etretched) out througl~ a tapering hole in a metal block or die, the die being more dense and harder than the metal to be redud. It is a fact well known to tllose slrillet1 in the ai*, that to eu~xeed in drawing iron or steel wire, it is of' the utmost, importance to have tborough lubritatiun, as a lack of it woullii udu-se abrasion of the wire, or of the walls of the tapering hole in the dia or plate, and quickly put an end to the operation. In drawing coarse or large sizes of pire, say & inoh diameter, the pressure upon the sides of the tay~dng hole, where the wire comes i.u contact with the die, so great that an ordina,y labricaot is equeezed out when the nsoal rc~luctions iu size are matie, and abrasion takea place. In order to meet this diffic:ulty, and emure proper lubrication, it has been a ccmmon prtictice for yazrs to apply a paste made of rye or wheaten flour, or lime, to the surface of the wire to be drawn, and when the pnstc is dry, to smwr tl~e wire with tallow or grease; the wire is then ready to be draw, the dried pa serving fo prevent the lubricant from being presetf out in the prows. Some years since, when Bessemer metal came iargely into use material for wire, 'the writer fourid that its dmwing requid so much more power than iron wire, that he was led to institute a. series of trials to ascertain the difference in power required. It was fotind that Bessemer wire requircd from 100 to 200 per cent. more power to makc the same reduction in sizes than soft iron wire, the difference depending npou the amount of carbon and other chemical constitu-

Jan 1, 1881

By George R. Cowan

A number of studies hare been reported of the effects produced in metals subjected to deformation by shock waves with maximum pressures ranging from tens to hundreds of kilobars. On the basis of the equations for the flow of mass, momentum, and energy through a stationary shock front, the macroscopic stress-strain curve for the resulting shock deformation can be calculated within narrow limits from the experimentally determined Hugoniol curve. In relatively weak shocks which are preceded by an elastic wave, the stress rises above the clastic limit only as plastic deformation proceeds cold thus the shock has a long toe. In strong shocks that override the elastic wave a high stress is applied without prior plastic deformation. A more important effect of increasing the shock pressure is the generation of shear stresses, called supercrilical shear stresses, that exceed the strength of the perfect lattice. A change in the mechanism of deformation is expected to result from the onset of supercritical shear. The shock disordering of ordered Cu3Au in strong shocks appears to be an example of such a change. It is suggested that the formation of fine twins in copper and nickel and the formation of structures which enable visible twins to be formed in the rarefaction ware, observed in copper and presumably in disordered Cu3 Au, are related to the occurrence of supercritical shear in shock dcformation. In recent years several studies1,2 have been made of the changes in structural and mechanical properties of metals produced by the passage through the metals of strong shock-compression waves ranging from about 50 to 800 kbar pressure. Recent work involving dynamic measurements of the shock compression "Hugoniot" curves 3-8 of many metals has developed techniques and provided data required to obtain the shock pressure and the (transient! plastic deformation produced in the shock-conlpression experirnents.9 Shock deformation has been found to be much more effective than slow deformation in changing the mechanical properties of metals, when the two are compared on the basis of equal plasti strain, Holtzman and Cowan9 made quantitative estimates of the shearing stress occurring in a shock front in a metal by assuming that the shearing stress is similar to that occurring in a shock front in a viscous, heat-conducting fluid, with the addition of a yield stress. Taylor's solution9 for a weak shock was used to estimate pairs of values of shearing stress and thickness of the shock front obtained by assumed choices of the ratio of effective kinetic viscosity to thermal diffusivity. It was noted from these values that. unless the shock front is extremely thin. heat conduction has slight effect, and the shearing stress is nearly independent of the mechanism of deformation. This mechanism does, however, determine the thickness of the shock front and the rate of strain. Furthermore, since the maximum possible shearing stress occurring in shocks of moderate strength does not greatly exceed the shear stress occurring in conventional slow deformation, the mechanism of deformation is not expected to be qualitatively different. The greater effectiveness of shock deformation in changing the mechanical properties of metals can be attributed partly to the fact that dislocations, when driven by near-conventional stresses, cannot keep up with the shock front, thus necessitating a higher dislocation density than required for an equivalent slow strain. The fast uni-axial strain occurring in the thin shock front would also be expected to cause a larger number of dislocation intersections to occur. In the upper range of shock pressures that have been studied the estimated values of the shearing stress exceeded the estimated shear strength of a perfect crystal. Under these circumstances it is reasonable to expect that the mechanism of deformation might be considerably different from that involved in slow deformation. Except for the observation by smith1 of twins in shocked copper, the effects of shock waves on metals did not show any obvious or large changes in properties that would indicate the onset of a change in the mechanism of deformation. The recent investigation of the effect of shock waves on ordered and disordered specimens of Cu3Au by Beardmore, Holtzman, and ever" showed a spectacular decrease in the amount of long-range order retained by initially ordered Cu3Au when the shock pressure was raised from 290 to 370 kbar. Since Dr. Holtzman and I suspected that this behavior probably was due to the onset of a shearing stress in the shock front in Cu3Au which exceeded the limiting shear strength of the perfect crystal. it was considered appropriate to examine directly the shock-front equations for a solid. and to obtain a sound estimate of the shearing stress occurring in the front using equation of state data obtained from shock studies. In this paper an estimate is made of the

Jan 1, 1965

By M. H. Shumate

Rope-type haulage has had many applications in the mining and allied industries. Records have indicated favorable results both from a standpoint of efficiency and investment. The Truax-Traer Coal Co. has used some variations of rope haulage at their mines and preparation plants. They have built a system which solves their particular problems, and have an investment which has indicated an annual savings in operating costs. Rope haulage, as applied to the mining industry, goes back many years for both underground and surface mining, or a combination of both. The Truax-Traer Coal Co. has used gravity retarding hoists as well as several variations of rope haulage, including electrical and combinations of both, but each was limited in its use and application by natural conditions and economies of the operation. Several systems of rope haulage equipment are offered by manufacturers today for handling railroad car movement on a limited or continuous basis. The portal and railroad loading facilities of Truax-Traer Coal Co.'s Burning Star Slope mine, located in Jackson County, Ill., were moved in 1960. The old location was abondoned, eliminating 3% miles of underground track haulage. The mine was converted to an all-belt system, and coal is loaded at a new raw coal plant and shipped by railroad cars to a central cleaning plant. The company wanted to operate the surface facilities as efficiently as possible, employing a minimum number of workers, using the latest type railroad car movers. The existing rope haulage facilities at several locations throughout the country were examined and considered for the Slope mine location. The application of each appeared favorable but lacked flexibility, and it was difficult to justify the capital investment. The company decided to investigate the possibility of building a system that would apply to their problem, and have an investment that could be amortized in a relatively short period. SPECIFICATIONS They employed the services of Allen and Garcia Co. of Chicago, Ill. Through combined efforts, a railroad car rope system was designed to specifications as shown in Fig. 1. The Falk Corp. of Milwaukee, Wis. built the hoist to the specifications as shown in Fig. 2. It has an all welded base and pedestals. The all welded drum is not grooved. A single helical gear was used in lieu of herring bone type. A Falk speed reducer, Unit 90Y3-A, is driven by a 25-hp 1800-rpm, 440-V ac type 'C' (high starting torque) drip-proof, Frame 324-U motor. The speed reducer shaft is equipped with a solenoid operated ac spring set shoe brake, operating on a 7-in. diam. brake wheel. The dolly car, shown in Fig. 3, was field constructed, using the trucks and frame of a railroad tank car. Truax-Traer did not alter the frame but added plates and anchors for hoist ropes and frames for 8.5 tons of concrete to be used as ballast on the car. The limit switch operating shoe was also installed and the car coupler latch mechanism overhauled. The hoist rope selected was 1% in. in diam., 6x37 improved plow steel extra flexible, right lay, regular lay, with independent wire rope core, and preformed. Wedge sockets were used to connect rope to the dolly car as shown in Fig. 4. The system employs two 30-in. and three 16-in. diam. sheaves. All are bronze bushed and equipped with grease fittings. Larger sheaves are used for directional change of hoist rope and the smaller ones as snub sheaves to correct fleet angle of rope as it approaches the hoist drum. The Trench lay cable, buried between the two tracks, is used for electrical distribution and controls between hoists and operator's cab. Foundations for the system required 187 cu yards of reinforced concrete using approximately 60 cu yd each at three locations. Four hoists are employed in the system, two for each track. A pair is interconnected electrically and when one operates, moving the cars, the tail hoist idles with brake released. The process is repeated for the reverse direction. A limit switch, mounted in the track near each end of the system, is tripped by the dolly car as it approaches the hoist. The limit switch controls movement in one direction only, protecting the dolly car and establishing positive con-

Jan 1, 1962

By Charles H. Morgan

THE process of wire drawing depends upon the property which certain metals possess, termed ductility, 'which is defined in Brande's Dictionary of Science as a property in consequence of which metals may be drawn out at length without interrupting the continuity of their constituent parts. As defined by M. Tresca, it is the property of flowing when subjected to pressure, and is termed by him the "flow of solids," in his paper, read before the Academy of Sciences in Paris, November, 1865 * In the simple language of the wire shop, it is that quality in certain metals that permit, them to be drawn (or stretched) out through a tapering, hole in a metal block or die, the die being more dense and harder than the metal to be reduced. It is a fact well known to those skilled in the art, that to succeed in drawing iron or steel wire, it is of the utmost importance to have thorough lubrication, as a lack of it would caws abrasion of the wire, or of the walls of the tapering hole in the die or plate, and quickly put an end to the operation. In drawing coarse or large sizes of wire, say 2/10 inch diameter, the pressure upon the sides of the tapering hole, where the wire comes in contact with the die, is so great that an ordinary lubricant is squeezed out when the usual reductions in size are made, and abrasion takes place. In order to meet this difficulty, and secure proper lubrication, it has been' a common practice for years to apply a paste made of rye or wheaten flour, or lime, to the surface of the wire to be drawn, and when the paste is dry, to smear the wire with tallow or grease; the wire is then ready to be drawn, the dried paste serving to prevent the lubricant from being pressed out in the. process. Some years since, when Bessemer metal came largely into use as material for wire, "the writer found that its drawing required so much more power than iron wire, that he was led to institute a series of trials to ascertain the difference in power required. It was found that Bessemer wire required from 100 to 200 per cent. more power to make the same reduction in sizes than soft iron wire, the difference depending upon the amount of carbon and other chemical constitu- * Interesting experiments in the flow of metals have been made, by Messrs. Hoopes Townsend, of Philadelphia, in cold-punching iron, published and illustrated in the Journal of the Franklin Institute, of March, 1878, by Mr. David Townsend.

Jan 1, 1881

By G. M. Schwartz

THERE has been considerable controversy regarding the structure and mineral constituents produced when iron ore is sintered. This investigation was undertaken in order to establish the fundamental reactions that take place in the sintering process by determining the nature of the resulting minerals. The writer's immediate interest in the subject arose mainly from the request of E. W. Davis for information based on a microscopic study of sinter submitted by him in May, 1926. In the author's preliminary work, samples of iron-ore sinter were secured from the Minnesota School of Mines Experiment Station and from commercial plants. These were polished by the usual methods for polishing opaque ores. In order to study these surfaces satisfactorily, it is necessary to magnify them rather highly, a range from 100 to 1000 dia. being used. For the higher magnifications oil-immersion lenses and an intense source of light are necessary. After the preliminary study had shown the problems involved, a series of small samples were sintered under carefully controlled conditions and with analyzed materials. Variations in the relative amounts of ore, coal and water were made in order to study the effect of each constituent. The attempt has been to arrive at a clearer understanding of the sintering process and the reactions involved without reference to any preconceived notion as to sinter. It is clear that the study of polished surfaces has yielded results not possible with thin sections alone. The thin sections made in this work were found unsatisfactory at magnification greater than 75, whereas magnifications of 1000 were easily studied with reflected light on carefully polished surfaces. A rather complete statement of observed facts is made so that the reader may form his own conclusions. The writer's interpretations are suggested.

Jan 1, 1929

EUGENE COSTE, ? Calgary, Alta.-Evidently in Argentine they have a petroliferous province just east of the Andes where very much the same conditions exist as are found on the east side of the Rocky Mountains and in the plains adjacent. It strikes me, though, that the same mistake is being made in Argentine in the exploration for oil as was made in Alberta, Canada; viz., drilling the wells too .near the seepages in the belt in the eastern part of the petroliferous province, too near the mountains. This same mistake was made in Alberta, with disastrous results; viz., only fissure production was found. The strata so near the mountains are tilted at a very strong angle, such as is described in this paper, and the dislocations are intense. On the other hand, we have found that when we get 100 or 200 mi. away from the mountains we get into oil and gas belts which are very prolific. So far our fields in Alberta have been gas, but in Wyoming, as you know, they get many thousands of barrels a day. I have no doubt that conditions in Argentine are exactly similar but that they have so far kept too near the mountains and that they want to explore the belts farther east to obtain better results.

Jan 4, 1919

By J. L. Christie, R. H. Leach

SO much has been written recently about the use of silver to replace scarce metals that certain facts about silver and its uses should be of interest. Figures for the production and use of silver, taken from the Handy & Harman annual reviews of the silver market, are given in Table 1. It will be seen that the rate of production has remained fairly constant and has been affected in recent years by the production of base metals, of which silver is a by-product. In each of the years 1937, 1938, and 1939, the U.S. Government acquisitions alone exceeded the entire world production, the difference, of course, being made up by imports of previously accumulated stocks. In 1940 and 1941 the U. S. Government acquisitions plus the United States and Canadian uses in the arts and industries exceeded the Western Hemisphere production. The U.S. Government pays a premium price for silver newly mined in the United States, at present 71.11c. compared with the price of 35'/8c. for foreign silver, with the result that the current U. S. production is not used commercially for the arts and industries. At the time this is written (June 1942) there is much uncertainty as to the future effect of this situation.

Jan 1, 1942

By John H. Walthall, Raymond L. Copson, Travis P. Hignett

In October 1942, the War Production Board requested the Tennessee Valley Authority to undertake investigations to determine the feasibility of producing alumina suitable for reduction in aluminum cells, from clays and other domestic materials, by a lime-sintering, soda-ash leaching process. The work was undertaken by the chemical engineering staff of the Authority under the general direction of the War Metallurgy Committee of the National Academy of Sciences. The investigation included small-scale tests to determine the most suitable conditions for the process, and construction and operation of a pilot plant to obtain data for evaluation of the process and for design of a plant. The results of this investigation are described in the present paper. Sources of Alumina Alumina for the commercial production of aluminum is obtained from bauxite by the Bayer process. The tremendous demand for aluminum for wartime uses is causing rapid exhaustion of the high-grade bauxite deposits in the United States. On the other hand, there is an abundance of aluminous materials such as clay and lower grades of bauxite, which are not suitable for treatment by the Bayer process because of their high silica content. The Tennessee Valley Authority has conducted research and pilot-plant work for more than 5 years on methods for the production of alumina from clay and low-grade bauxite. Particular attention has been given to the high-grade white kaolin found in Carroll County, Tennessee. Exploratory drilling has demonstrated that at least 4 1/2 million tons of kaolin containing in excess of 34 per cent AlzOI is available in this area by strip-mining methods. It has been estimated that hundreds of millions of tons of clay of similar quality occur in the Tennessee Valley region. The Process The process is illustrated in the flowsheet (Fig. I), and consists essentially of the following steps: I. Heating a mixture of clay and limestone to form a sinter containing calcium aluminate and dicalcium silicate. z. Leaching this sinter with a dilute sodium carbonate solution, to form a sodium aluminate solution and a calcium carbonate, calcium silicate residue, which is discarded. 3. Treating the sodium aluminate solution with carbon dioxide to precipitate aluminum trihydrate and regenerate the sodium carbonate solution, which is recycled. 4. Heating the aluminum trihydrate to produce alumina. The process was considered promising because of the abundance and cheapness of the two raw materials, clay and limestone; and because, as compared with an acid process, smaller amounts of critical

Jan 1, 1944

By B. Chalmers, Stefan Wojciechowski

Rotary oscillation of the mold has been used to produce mechanical stirring of the melt during unidirectional solidification. Al-Cu alloys (1 to 4 wt pct Cu) were solidified to study the influence of alloy composition, temperature at which intensive cooling was initiated, and intensity of stirring on the temperature distribution in the sample, the resulting structure, and the copper microsegregation at the columnar to equiaxed transition. The Proposed explanation for the equiaxed solidification in stirred castings consists of the melting off of dendrite fragments, their partial remelting in hotter liquid, and the subsequent growth of the surviving part when the temperature of the melt is lowered. This may result in the formation of a crystal network, which can stop the growth of the columnar crystals and produce the equiaxed zone. It has long been known and many times affirmed that ultrasonic vibrations or relative motion of liquid and solid can significantly reduce the length of the columnar zone and refine the grains in the equiaxed zone in ingots and castings. Because of the technological importance of these phenomena many investigations have been conducted in which ultrasonic energy or mechanical vibration,1-6 electromagnetic stirring,7"10'17 magnetic stirring,"'12 or mechanical stirring13'14 were used to produce the relative liquid-solid motion. More recently, the question of the importance of natural (or thermal) convection has been raised.15-l7 Several possible mechanisms have been suggested.l,8,18-20 They can be divided into two main groups. The first group includes such nucleation hypotheses as nucleation frequency enhancement due to cavitation at the mold wall or other surfaces; cavita-tion in the body of the liquid resulting from the pressure wave, or an agglomeration mechanism, which involves the formation of nuclei by the accretion of subcritical nuclei. The second group considers the grain-refining action to be due to crystal multiplication phenomena such as the removal of the dendrite fragments by viscous forces or by a high-pressure cycle following cavitation or by a melting-off process. Sbme recent investigations give good experimental support to the melting-off proposa1.21-23 The purpose of the present study was to examine the effect of mechanical stirring during the unidirectional solidification on the structure of alloy samples and on the solidification variables. The motion of the liquid was produced by rotary oscillation of the mold around its vertical axis.

Jan 1, 1969

IT may perhaps seem to you that I have deviated from sequence by having entered into the narration of this arrangement of the bellows, but, although they are not furnaces or vessels for containing the melts, they are essential agents for bringing to port the bark of your labors. Returning to our regular pathway, and supposing that, besides making the moulds, you have melted and cast not only statues and bells but also guns, it is true that a certain procedure is required in order to finish them. For this you should have the moulds full, and they should have come out very well, for in truth reason does not allow that they turn out otherwise for one who uses precaution. [II2V] Then you have taken your casting from the pit and have freed it of clay. Since I have told you nothing beyond this, do not be dismayed if you see the castings so rough and in a form that scarcely shows what they really are, for I wish to open up part of the way into the great labor of finishing them so that it may seem to you that you have been somewhat helped by me. Therefore, when it is a gun, first see that the iron spindle that has been placed in the middle of the core is taken out. You can do this easily by striking the heel of the core, especially if the spindle had first been covered with ashes, hemp, or a little rope. Then saw off the feeding head above the mouth, using either a dun steel saw with tiny straight teeth that has been tempered with oil or some other fat, or a hay sickle whose edge is gently hit by a little hammer. Then have the clay that is attached to the curls or other bronze parts lifted away with a chisel. Then with a scouring brush and water uncover the emblems, coats of arms, borders, and cornices that you made as ornaments. Striking it with a hammer, push inwards every superfluous bit of bronze. Finally, having cleaned the bronze by washing, scraping, and cutting away every bit of clay, strike its surfaces gently with a large hammer and thus make it very smooth. Likewise finish the mouth and all its cornices as exactly and completely as possible with files and any other instrument that serves best. Then take a long, powerful tool that has some steel on the point, made like a chisel and somewhat bent, or with three points like the iron blade

Jan 1, 1942

By F. R. Wadleigh

It is generally realized and very often admitted by both producers and consumers of coal that there is great need for a revision of existing commercial classifications, and this will involve, of course, determination of a standard classification and a constant revision of marketing practices as they are affected by coal classification. I recently sent out some 200 letters to producers and consumers with a request for their views on the subject of commercial classification. Nearly all of the replies from both sides were that there was needed some change in the present method. There were three or four dissenting voices but the great majority of opinion was in favor of the formulation of some standard commercial classification. The classifications in commercial use today can best be described as a hodgepodge. They are made upon different bases, have different names and have different ways. There are, for instance, about 11 single bases of classifications as used commercially and some 17 or 18 combination bases. Then there were the Tidewater Pool Exchanges. The classification which they put in force is still used in the tidewater markets and has several different bases of its own. It will be considerable of an undertaking to bring about a change in marketing methods as affected by coal classification but it is well worth doing and I think the committee which has been appointed under the auspices of the American Society for Testing Materials realizes the importance of the subject and is on the way to at least bring about some provision for adjusting matters. By way of starting, each member of the Committee on Commercial Classification has been assigned to a general market district and each member is now engaged in collecting the commercial market practice data for submission at the next meeting of the Committee. About a year ago I made up a list of the commercial classifications in the different markets and the total was 171. The 11 single bases I found used in commercial practice were:

Jan 1, 1930