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By John F. Wiggert

DURING the early years of Homestake operations, shaft signaling from the cage tenders to the hoisting engineers was done by mechanical means. Small steel cables or jointed steel rods were suspended in the shaft compartments and counterbalanced with weights or springs. These cables or rod strings were connected to the mechanically operated gongs at the engineers' stations by means of bell cranks and steel wires. The system was simple and economical and served the purpose well until the mine reached a depth of 1000 ft., then the system became slow and cumbersome and required a considerable amount of muscular effort to operate it with much speed, because of the inertia of the heavy moving parts. The mechanical signaling was superseded by a simple electrical system consisting of a single pair of wires in steel conduit for each shaft compartment. In the shaft at each station a pull switch was connected to the wires. The switches were operated by means of bell cords, which extended from station to station. This electrical system was a great improvement over the mechanical one, but it had one serious drawback, which also applied to the older system; namely, the engineer did not know where a signal originated. Later on this signaling was improved to overcome this drawback, and to give the engineer a positive indication of a signal's origin. In this system a separate return wire from each pull switch is carried to an annunciator at the engineer's station, where it indicates the signal's origin. While the annunciator system used by Homestake is very safe and reliable, it has the inherent drawback of all wire-connected systems in that it is impossible to send a signal from a moving cage. A number of years ago Homestake became interested in the possibility of using some sort of radio transmission for shaft signaling. The company did much experimental work with purely radio signal transmission, but no practical way was discovered to use radio transmission in a mine shaft for signaling to or from a cage. Therefore, all efforts were directed to devising a practical way of using the hoisting rope as part of the circuit. It was realized that the return circuit from the rope would need to be through electrostatic coupling between the cage and the earth or ground sides of the shaft, because the guides would not always be wet enough to make possible good electrical contact between the cage and earth, therefore relatively high-frequency alternating current was chosen as the medium of transmission. Soon a practical system was developed for transmitting an electric current from a moving cage over an electric circuit of which the hoisting rope was a part. A high-frequency electric current is used as a carrier to transmit the signals or mes-

Jan 1, 1941

By Robert H. Richards

This is in part a review paper, indicating the various steps that have been taken in developing hindered-settling apparatus, some of the standard data that have been obtained, and some of the conclusions one is led to as to the effect of it in improving concentrating-methods and machinery, and in part it brings in some unpublished work. Causes oF Loss in ORe-ConcEntration. In making a study of the separation of valuable minerals from the waste gangue, particularly by water concentrators, it is necessary to define, first of all, what are the causes of loss that are likely to interfere with the concentration. Having made this definition, we can then study to see in what may the machines make their losses, and plan remedies for them in an intelligent way. Losses may be stated to occur as included grains, as flat or long grains, as fine free mineral, and as absolute slime. We will take these up one by one, as follows: Included Grains.—Fig. 1 shows by a set of diagrams how included grains may occur : first, where the heavy mineral grains attached to the quartz are of large size; secondly, where they are of small size; and thirdly, where very fine particles of heavy mineral are included in the quartz. We have to decide in regard to included grains whether they are rich enough to go direct to the furnace, or poor enough to throw away, or whether they lie between these two points and require recrush-ing as the only means of severing the values from the waste. This last case is the orlly one requiring special treatment at our hands. We will therefore consider that next.

Jan 1, 1911

By Charles S. Barrett

THE experiments reported in this paper have been fruitful in disclosing the mechanism of the deformation of iron in compression. They have established the nature of "deformation bands," "etch bands," or "X-bands," that have been a recognized but little understood feature in the structure of cold-worked metals since the early days of metallography, and have shown the role of the bands in the development of preferred orientations by cold-working. The work has also shown the relation of the orientation of individual grains to the preferred orientation of the aggregate. Some of the methods previously used in the determination of the indices of slip planes and slip directions are shown to be untrustworthy in the presence of deformation bands. The conclusion is reached that many slip planes and slip directions must operate during each stage in the compression of a single crystal, and that theories failing to take account of this require revision. In conducting the experiments a method of compression has been used by which extreme reductions can easily be reached, even to the limit set by the metal's capacity to deform without fracture. The work is a portion of a research program on the plastic properties of iron and steel. It is being used as a foundation for studies of orientations resulting from recrystallization and is being extended to other metals and other types of deformation. PREVIOUS WORK The previous experiments are few and have given confusing results. Ono1 compressed a polycrystalline alpha-iron specimen between two flat plates of a testing machine and found that severe deformation oriented the crystals into a duplex preferred orientation, one set of crystallites having a cube diagonal of the body-centered cubic lattice parallel to the compression axis, and another set having a cube axis parallel to the compression axis. We shall speak of this structure as a. double fiber texture of the type [111] + [100]. Wever2 also made an X-ray determination of the texture

Jan 1, 1938

By William G. Kegel

Apart from a usable product and good mining conditions, the greatest asset for a profitable coal mining organization is an effective mine maintenance program. The first step in achieving this is to have good mechanics-or men who want to be mechanics and are interested in knowing, more about the design and control of the machines in their charge. A good mechanic's knowledge and ability result from ambition, curiosity, and determination. Starting with these qualities, the aspiring mechanic can launch his career by learning all he can about mechanics, electricity, and hydraulics. Though the path is rough, the end result is rewarding. Mining machinery probably receives as much, if not more, abuse as any other heavy equipment in use today. Considering the conditions under which much of the repair work must be done, it is essential that the mine operator has the best men and tools to perform the work. Mining machines, from their inception, have utilized the electric motor; and down through the years of mechanization, this power source has undergone many changes to better adapt it to the job. The first motors used were direct-current (d-c) motors since d-c power was the most economical power source for mining at the time of early mechanization. These motors were large open-type machines which are seldom used in modern mining. Because of the mine environment, the d-c motor has been reduced in size to better suit the application in mining machines and is now manufactured with dust-tight or explosion-proof enclosures. The d-c motor is constructed with either (or both) series and shunt fields located on the stationary part of the motor (stator) and an armature coil wound on the rotating part of the motor (rotor). Power is supplied to the armature by brushes which are held stationary and make sliding contact with the armature. The brushes requires regular and careful maintenance because worn or defective brushes will cause heat or arcing which can destroy the motor. D-c motors can be used as d-c generators when mechanical power is supplied to them by the rotating

Jan 1, 1981

By R. G. Bowman

Discussions of processes for the manufacture of white lead generally open with the statement that white lead is the oldest chemical pigment known to man. This fact is of more than historical interest; in the light of the present extensive use of white lead, it indicates that the compound possesses characteristics that make it unique among white pigments, and superior to all in its particular field. A greater variety of processes have been proposed for manufacturing white lend than for any other one chemical compound. Only a few of these processes have come into commercial use, however, and a large part of the present production here and abroad is made by the process used in ancient times. The outstanding disadvantages of the old process are that it is slow and laborious, affords no control of the product, and yields at best an impure material lacking in uniformity. Improved processes, sometimes classed all together as "quick processes," have had as their main object the shortening of the time required. Most of them accomplish this and some have yielded a superior product as well, but only two or three are now in use commercially. For centuries the manufacture and mixing of paints have been treated as an art, and the practice has been much influenced by tradition and precedent. There is a reluctance to abandon old materials for this purpose, and as few new uses for white lead have been developed, the adoption of the quick processes has been slow. The electrolytic production of white lead is not new, a large number of processes and forms of apparatus have been proposed and patented within the past 25 years, all directed toward the production of white lead, wholly or in part, by electrolysis. One or two of these processes were tried commercially but proved unsuccessful. Process The Sperry process, used by the Anaconda Lead Products Co., is the invention of Elmer A. Sperry, and was worked out to a commercial basis at the East Chicago plant. It resembles, in a general way, earlier methods, but embodies the features that make it possible to operate

Jan 1, 1926

By C. S. Barrett

THE crystal imperfections known as faults in stacking (stacking disorder) are of importance to both fundamental and applied science and are receiving increasing attention. On the theoretical side there have been recent advances in the analysis of diffraction patterns in terms of stacking faults, and on the experimental side it has been found that certain metals develop a faulted structure on cooling through a phase transformation. Beyond this, little is known of what may be called the physical and mechanical metallurgy of faulting, although there has been no lack of discussion and conjecture as to the presence of faults in metals and the effect of faults on mechanical properties and microstructures. In the close-packed metals the nature of faults can be described very simply. Face-centered cubic (FCC) crystals consist of close-packed layers of atoms, (111) planes, stacked above each other in a definite manner. If one layer is designated as the A layer, the next must be a B or a C layer; that is, every atom of the second layer lies not above the atoms of the A layer, but nestles in the hollows between these, using the hollows designated as the B positions, or the equivalent hollows designated as C. If the sequence of layers is ABCABC...., so that layers three spacings apart are directly over each other, the crystal is FCC; if CBACBA ... it is an FCC crystal that is a twin of the former; if ABAB........or BCBC..it is hexagonal close-packed (HCP). A fault is a break in the sequence, such as ABCABABC .. . which has the effect of inserting an HCP lamella into an FCC crystal. Regularly spaced faults spaced two layers apart would convert an FCC crystal entirely to HCP, or an HCP to FCC. A fault in an FCC crystal is also equivalent to creating an FCC twin of minimum thickness; in fact, the entire crystal would be converted to its twin if faults were introduced regularly. (In HCP crystals, however, twinning does not occur on the basal plane and a fault on this plane is not identical with a thin twin). Faults are one of the possible causes for annealing twins,' for the strain markings that are brought out by etching deformed metal,'," for the altered X ray reflecting power of metal at slip bands that is revealed in X ray reflection micrographs,' for the extinction of Kikuchi lines in electron diffraction patterns, and for the hardening of latent slip planes.' Since other explanations of these effects are also available," there has been no direct proof of faults from deformation; yet it has appeared likely that they would occur. Faults resulting from phase transformations in metals, however, have been clearly revealed by diffraction in cobalt" and lithium. It is to be expected that the faulting tendency is greatest

Jan 1, 1951

By V. Jares

DESPITE the fact that a combination of metals-aluminum-zinc-tin, and sometimes aluminium-zinc-cadmium-is extensively used for aluminum solders, as well as for die-castings, the constitution of these alloys has not yet been made clear. I. BINARY SYSTEMS The system aluminium-zinc is the basis of the ternary alloys under consideration. Their composition was made sufficiently clear by the investigations of Roscnhein and Archbutt,1 Bauer and Vogel,2 Sander .and Meissner,3 Hanson and Gayler4 and Isihara.5 Only the temperature of decomposition of the crystals s seems still to be doubtful, whether it is considered as a compound of Al2Zn3 (according to Bauer and Vogel) or as an intermediate phase of variant composition (according to Hanson and Gayler). This temperature is given by most of the authors, as in the neighborhood of 256° C., only Isihara giving 280° C. As its accurate determination is of special importance in the study of the ternary alloys under consideration it was experimentally controlled in the following manner: An alloy corresponding in composition to the formula Al2Zn3 was made, in which the temperature effect was found to be the greatest. This was drilled and a silver-constantan thermoelement inserted into the cavity so as to be in direct contact with the alloy. The whole was then very slowly heated and the heating and cooling curves determined. The transition temperature from the heating curve was found to be 281° C., whereas-from the cooling curve it was 252° C.

Jan 10, 1926

By C. Y. Clayton, Francis B. Foley, Muir L. Frey

DuRing the past year, we have investigated the cause of 88 per cent, of the failures by breakage near the bit end of some 1-in. hollow, hexagon, drill steel used in a metal mine. This breakage in the region of the bit end of the steel was peculiarly interesting because we have been Ied to believe that breakage is most prevalent at the shank end of drill steels near the place where the steel is gripped in the chuck of the machine. Records from the mine showed, also, that the breakage was much more frequent in the short lengths of large gage than in the longer steels; this is shown graphically in Fig. 1. Because the shorter lengths of steels are usually those that have been made from broken pieces of long steels or from steels that have worn down in service, rarely being made from new stock, those who are wont to suspect steel of tiring and crystallizing in its old age through fatigue are quite apt to see in this instance an argument in favor of their idea. As usual, a careful examination of these steels reveals defects of a character hardly to be overlooked in favor of such a cause. The steel in question was rolled with a sand core and was of the usual drill steel composition: Carbon 0.85 per cent., manganese 0.60 per cent., silicon 0.25 per cent., phosphorus 0.02 per cent., and sulfur 0.02 per cent., with the exception that in some specimens there was vanadium, not exceeding 0.20 per cent. The following lengths and gages were used: LenGth, GaGe, LenGth. GaGe, Feet Inches feet Inches Starter 2 % 7 111/16 3 2 % 8 11 4 2 % 9 1 9/16 5 2 10 1 7/16 ________6_____________115/16____________________________

Jan 1, 1924

By John S. Johnson, Thomas Fraser

SIZING is the process of separating mixed particles into groups of particles all of the same size, or into groups in which all particles range between certain definite maximum and minimum sizes. In coal preparation, sizing is generally accomplished by passing the coal over screens. Separation by differential settling in air or water currents has been adapted to the special field of separating very fine sizes, and these processes are in commercial use to a relatively small extent in the coal industry. Separation with screens is a very old industrial practice. Agricola described the use of screens for ore treatment in the middle ages. In the literature of the British coal industry references were made to the screening of coal as early as 1589, but the practice of extensive sizing for the market did not become general until the last half of the nineteenth century. In America, the practice of sizing developed first in the Pennsylvania anthracite region, beginning with the use of rakes' in the mine working places to recover coarse coal. This mining procedure left the fines in the mine. Preparation outside the mine started with the installation of station¬ary cast-iron plates with 4 to 6-in. square holes. The run-of-mine coal was dumped upon the platforms, the large pieces of rock were picked out by hand, and the large lumps of coal were broken with hammers. The term "breaker," which still applies to the anthracite-preparation plant, originated with this practice, but the term is no longer descriptive of the entire function of the plant. In 1884, the first power-operated anthracite coal breaker' was erected by Gideon Bart at his colliery at Wolf Creek near Minersville, Pa. This plant utilized a system of rolls for breaking the coal and revolving screens for sizing. The plant was driven by a steam engine. It 'could handle

Jan 1, 1943

By M. Muskat

A theory has been developed describing the behavior of wells and reservoirs producing by the action of bottom water drives. It is assumed that the pressures are maintained above the bubble point, and that the permeability to viscosity ratio of the water in the flooded zone is the same as for the oil in the oil-saturated pay. Accordingly, the treatment is based on the homogeneous fluid potential theory. The effect of the difference in density between the oil and water is neglected. .4fter deriving the proper potential distrihutions, the nature of the rise of the water-oil interface below the producing wells is calculated. The primary clean-oil-production phase is expressed in terms of the displacement efficiency, defined as the fraction of the pay flooded out by the rising water table at tlle time of first water entry. The variation of this displacement efficiency is calculated as a function of the well spacing, pay thickness, the ratio of the horizontal to vertical permeability, and the well penetration. The important parameter, other than the well penetration, is found to be the ratio of the well separation to the thickness of the oil pay multiplied by the square root of the ratio of vertical to horizontal permeability. It was found that the displacement efficiency continually decreases as this parameter increases, and for values of the latter >3.5, the efficiency varies inversely as the square of the parameter. It also increases with decreasing well penetration. Perhaps the most striking result of this phase of the analysis is the conclusion that in order to explain the delay in entry of water in wells producing by bottom water drives for periods longer than a few days normal production, with drawdowns large compared with the differential density head between the oil and water, it is necessary to assume that the vertical permeability is a very low fraction of the horizontal permeability. An analysis is also given of the production history after the water has broken through, on the assumption that the production mechanism and details of the flow distribution continue to be the same as during the phase of clean-oil production. As is to be expected, it is found that the water cut will increase at an accelerated rate as production proceeds. However, the initial differences between systems of different well penetrations or well spacings with respect to the total clean-oil production gradually decrease in terms of the variation of the water-oil ratio with cumulative production. In particular, by the time the water-oil ratio has reached values of the order of 5 or greater the cumulative recoveries will generally differ much less among various producing systems than their corresponding clean-oil recoveries. Introduction On the basis of elementary geological principles, one may classify effective water-drive fields in two groups. In the first, the entry of water into the oil-producing formation may be characterized as an edge-water encroachment. This term is used to suggest that the motion of the water proceeds largely in a direction parallel to the planes of stratification. This type of water intrusion occurs usually in thin producing zones and in strata lying along structural flanks of appreciable dip. In the second group—"bottom water-drive" fields—the water-oil interface lies in a plane of zero or slight inclination to the

Jan 1, 1947

By M. Muskat

A theory has been developed describing the behavior of wells and reservoirs producing by the action of bottom water drives. It is assumed that the pressures are maintained above the bubble point, and that the permeability to viscosity ratio of the water in the flooded zone is the same as for the oil in the oil-saturated pay. Accordingly, the treatment is based on the homogeneous fluid potential theory. The effect of the difference in density between the oil and water is neglected. .4fter deriving the proper potential distrihutions, the nature of the rise of the water-oil interface below the producing wells is calculated. The primary clean-oil-production phase is expressed in terms of the displacement efficiency, defined as the fraction of the pay flooded out by the rising water table at tlle time of first water entry. The variation of this displacement efficiency is calculated as a function of the well spacing, pay thickness, the ratio of the horizontal to vertical permeability, and the well penetration. The important parameter, other than the well penetration, is found to be the ratio of the well separation to the thickness of the oil pay multiplied by the square root of the ratio of vertical to horizontal permeability. It was found that the displacement efficiency continually decreases as this parameter increases, and for values of the latter >3.5, the efficiency varies inversely as the square of the parameter. It also increases with decreasing well penetration. Perhaps the most striking result of this phase of the analysis is the conclusion that in order to explain the delay in entry of water in wells producing by bottom water drives for periods longer than a few days normal production, with drawdowns large compared with the differential density head between the oil and water, it is necessary to assume that the vertical permeability is a very low fraction of the horizontal permeability. An analysis is also given of the production history after the water has broken through, on the assumption that the production mechanism and details of the flow distribution continue to be the same as during the phase of clean-oil production. As is to be expected, it is found that the water cut will increase at an accelerated rate as production proceeds. However, the initial differences between systems of different well penetrations or well spacings with respect to the total clean-oil production gradually decrease in terms of the variation of the water-oil ratio with cumulative production. In particular, by the time the water-oil ratio has reached values of the order of 5 or greater the cumulative recoveries will generally differ much less among various producing systems than their corresponding clean-oil recoveries. Introduction On the basis of elementary geological principles, one may classify effective water-drive fields in two groups. In the first, the entry of water into the oil-producing formation may be characterized as an edge-water encroachment. This term is used to suggest that the motion of the water proceeds largely in a direction parallel to the planes of stratification. This type of water intrusion occurs usually in thin producing zones and in strata lying along structural flanks of appreciable dip. In the second group—"bottom water-drive" fields—the water-oil interface lies in a plane of zero or slight inclination to the

Jan 1, 1947

By H. S. Kalish, F. J. Dunkerley

INTRODUCTION AND PREVIOUS WORK THE determination of the low temperature tensile properties of tin and tin-lead alloys was initiated as part of an extensive research program on the phasial equilibria of tin binary systems below 13.2°C and the property changes associated therewith. A survey of the literature revealed that, although some room temperature tensile data were available for tin and a few tin-lead alloys, there existed no survey report of the low temperature tensile properties of these alloys. Accordingly, the tensile data for tin and a series of pure tin alloys containing from 0.01 to 50 pct lead were measured at eleven temperatures from -196 to +20°C and are presented here in survey form. In addition to the importance of these tensile data as a preliminary to certain fundamental research, this information promises also to be of commercial importance because of the 'extensive use now being made of tin-lead solders in refrigeration and gas liquefaction equipment. Occasional failures of the solders in low temperature service have been attributed by some metallurgists to low temperature mbrittlement, while others hold that failure results from the transformation of the tin-rich phase of the solder from the solid white (beta) to the powdered gray (alpha) form. From the data previously available in the literature, neither of these explanations can be completely corroborated. Cohen and van Lieshout1 have established the beta to alpha tin transformation at 13.2°C and have shown that strain accelerates the transformation. Further, they showed that although I pct lead retarded the transformation, it was not eliminated. It will be pertinent, then, to note whether the beta to alpha transformation of the tin-rich phase will occur in a short-time tensile test. Polanyi and Schmid2 studied the tensile . properties of tin single crystals at -185°C and report that tin is brittle at-this temperature. In 1946, Kostenets3 reported that pure tin was brittle at -196 and -253°C, while lead remained ductile at both these temperatures. He also studied the tensile properties of tin-lead alloys containing from 10 to 75 pct lead at -253, -196 and +17°C. The ultimate tensile strength increased more than two times in going from room temperature to -196°C and about three times that value on further cooling to -253°C. All the alloys were brittle at -6°C except those containing more than 75 pct lead. Even at -253°C, the 75 pct lead alloy retained 36 pct elonga¬tion in a 30 mm-ga. length. Creep is also an important phenomenon

Jan 1, 1948

By Henry Lloyd Smyth, J. Ralph Finlay

The most important area of the so-called Keewatin rocks of northern Minnesota is that which runs westerly from Lake Saganaga, near the national boundary, and finally disappears beneath the drift (or has not been farther traced), in the neighborhood of Vermilion Lake. With this belt we have a general acquaintance, extending back some four years. During the past year we have had the opportunity of studying in considerable detail a small part of it, embracing an area of about 12 square miles on the south and east shores of Vermilion Lake. In this paper we desire to record our observations and conclusions, which seem to us important. II.—Literature. Outside the Minnesota Geological Survey, the list of the investigators who have studied the geology of the Vermilion Lake area is not long. Whittlesey, in 1876,* mentioned the occurrence, in the area about Vermilion Lake, of rocks resembling the Canadian Laurentian. Chester,? in 1884, described the iron-ore at Vermilion Lake as occurring in connection with jasper and quartzite, intimately bedded with the country-rock, chiefly sericite schist, and standing in a nearly vertical attitude. The Vermilion iron-bearing rocks, and those of the Mesabi range, he says, are of the same age.

Jan 1, 1896

Jan 1, 1951

By Rudolf Gahl

Page Tests Conducted in Small Test Mill................... 577 Demonstration Tests Conducted by Minerals Separation Co....... 577 Flotation Tcsts Conducted by Inspiration Co............. 577 Sampling of Orebody........................ 578 Other Results Obtained in Small Test Mill.............. 580 Tests Conducted in Large Test Mill................... 580 Flow Sheet............................. 580 Discussion of the Value of Preliminary Table Treatment......582 Callow Flotation Installation..................... 585 Flinn-Towne ~nstallation...................... 587 Cole-Bergman Installation...................... 588 Methods Followed in Competitive Tests................ 590 Advantage of Pneumatic Flotation Machines.............. 591 Pneumatic Machines of Minerals Separation Co............. 591 Float Skimming Device......................; 594 Experimental Inspiration Flotation Machine.............. 596 Arrangement of Callow Cells in Series ................ 598 Variations of Flow Sheet....................... 599 Coal Tar as Flotation Agent..................... 600 Experience with Primary Slime.................... 602 Influence of Iron on Flotation..................... 605 Influence of Chemicals on Primary Slime............... 607 Fineness of Crushing Desired.................... 607 Operation of Large Concentrator..................... 608 Flow Sheet of Callow Sections.................... 608 Flow Sheet of Inspiration Sections.................• 609 Inspiration Flotation Machine of Steel Construction.......... 610 Minerals Separation Section..................... 613 Filter Plant............................ 613 Results Obtained in Commercial Concentrator............... 616 Tonnage............................... 616 Air and Power Consumption...................... 616 Floor Space............................ 617 Water Consumption......................... 617 Recovery............................. 618 Oil Consumption.......................... 618 Operating Costs for Flotation..................... 620 Discussion of Results Obtained.................... 620 Prospects for Futurc Development of the Flotation Process......... 621 Porous-Bottom Experiments..................... 622 Raising the Grade of Concentrates.................. 624 Recovering Carbonates by Flotation................. 624 Recovery of Silicates by Flotation.................. 627 General Theory......................... 628 Conclusion............................... 630

Jan 1, 1917

By F. L. Wolf

The catenary system of line construction possesses so many desirable characteristics from the operating standpoint that it has wide application for all types of electric traction. Many steam roads are electrifying sections of their lines, and in most cases are operating both steam and electric locomotives over the same track. This means that the overhead catenary system is subjected to the severe corrosive action of locomotive smoke, and data concerning the resistance of various alloys to this form of corrosion are very desirable from every point of view. Reliable and specific information and data on the subject of corrosion due to steam and smoke from locomotives are extremely meager and, on this account, extensive service tests, together with accelerated tests, have been made on a number of commercial metals and alloys. The observations and data recorded in this paper are the result of a preliminary test which was started in 1923 and which has been carried on to the present time. The recognition of the need for even more detailed and accurate data has resulted in the undertaking of another test which has been in progress for about a year. The result of this test will be published in due course. Some years ago The Ohio Brass Co. was asked by one of the large steam railroad companies to furnish data on construction details for a catenary system which it was considering for one of its divisions. The selection of materials which would give the necessary physical characteristics as well as withstand the severe corrosive action of locomotive gases caused electrical railroad engineers considerable concern. At that time, there were available no specific or authentic data on these important questions: no systematic investigation of the problem appeared to have been made, even though it's importance was generally recognized. Such observations as had been made were crude in that they had been limited largely to visual inspection which too frequently is most misleading. However, the scattered information which was collected gave important clues as to how best to start an investigation. Technical literature was studied, metallurgical experts were consulted, and the problem was discussed with engineers who were in close contact

Jan 1, 1930

By Stanley J. LeFond, Langtry E. Lynd

Elemental titanium has become famous as a space age metal, because of its high strength/ weight ratio and resistance to corrosion. However, the major use is in the form of titanium dioxide pigment, which because of its whiteness, high refractive index, and resulting light-scattering ability, is unequaled for whitening paints, paper, rubber, plastics, and other materials. A relatively minor use is in welding rod coatings, in the form of the mineral, rutile. United States consumption of titanium dioxide for these applications in 1973 was as follows: pigments, 891,000 st; titanium metal, 40,000 st (=24,000 st metal) ; and welding rod coatings, 10,000 st. The only commercially important titanium ore minerals at the present time are ilmenite, and its alteration products, and rutile. Titanium was discovered by Gregor in 1790, as a white oxide which he recovered from menaccanite, a variety of ilmenite occurring as a black sand near Falmouth, Cornwall. Barksdale (1966) states that the fundamental chemical reactions on which the present day titanium industry is based were known before 1800, although it was not until 1918 that these pigments were available commercially on the American market. Pings (1972) outlines the early history of the titanium industry in the United States, referring to the work of Guise (1964) and others: "Mining of titanium minerals in the United States began sometime between 1880 and 1900, in Chester County, Pennsylvania. Small quantities of rutile were also produced during the time in North Carolina and Georgia. In 1901 rutile was mined from a deposit near Roseland, Va., and was used in making titanium chemicals and for coloring ceramics. Ilmenite in the deposit was produced as a separate item in 1913, and rutile and ilmenite were obtained from this deposit through 1921. The mining of titanium bearing beach sands began in 1916 near Mineral City and Pablo Beach, Fla., for the purpose of making titanium tetrachloride to be used in tracer bullets, flares, and smokescreens. The titanium pigment industry was founded in 1918. By 1928 a large part of the domestic production of rutile, ilmenite, and zircon came from Florida. However production ceased in 1929 in Florida with the mining of newly discovered deposits in Virginia which were mined until 1968. The discovery of new deposits in Florida, and the development of better mining and concentrating methods for lowgrade sands, led to a return of activities in this area. The large deposits near Tahawus, N.Y., were brought into production in 1942 by National Lead Co. (now N L Industries Inc.), and by 1949 this company was the lead¬ing producer of ilmenite in the world. In 1948 the extensive deposits of ilmenite and ilmenite-bearing iron ores were discovered in eastern Quebec." The beginning of the modern titanium metal industry was in 1948, when E. I. du Pont de Nemours & Co. produced the first metal. U.S. Bureau of Mines reports, which gave details of the Kroll process, together with the attractive properties of the metal for

Jan 1, 1975

By R. G. Hall

WHEN we want to interpret some problem which faces us at the present, if that problem be a social or political movement, we turn to the pages of history for 'information. If the problem be one of science or of industry we turn to the library of the subject and endeavor to translate the present from the experience of the past. I wonder if you would bear with me for a few minutes as I look back to the time when I was going through mining school and looking forward with hope, it is true and with confidence also, but still with some trepidation and an occasional qualm, to the month of June when the class of 1897 would be hunting jobs. Those were the years 1893 to 1897. Those years saw the Treasury of the United States so empty of gold that the President had to appeal to financiers to accept the country's promises to pay in return for $100,000,000 in gold. And the invectives that were hurled at both their heads for such a betrayal of the people sound strangely similar to those you read today being daily written and screamed at another President for taking us into the League of Nations or for not issuing bonds in huge amounts for unemployment relief, or for not adopting somebody else's particular specific for the relief of hard times.

Jan 1, 1931

By G. W. Preckshot, N. G. DeLisle, C. E. Cottrell, D. L. Katz

MOST crude oils contain asphaltic substances that may be naturally or artificially precipitated. In the Greeley field, California, this asphaltic bitumen is precipitated during the flow of the oil from the reservoir to the stock tank. The mechanism of such precipitation is not well understood. This paper presents the progress that has been made by using the electron microscope as a new tool and by observing the effects of the streaming potential on the formation of bitumen particles. Crude oils at atmospheric pressure viewed in the electron microscope in very thin films under a vacuum showed no asphaltic particles. A technique of preparing slides of thin films by dilution of the oil with benzene and washing in petroleum ether was used at first, and these observations showed that the solvents caused the formation of the particles, varying from 0.01 to 0.2 micron in diameter. The electrical effects of fluids flowing through porous solid were studied, with emphasis on the formation of colloidal particles by the streaming potential. The streaming potential of crude oil flowing through sand was measured and was shown to be responsible for the formation of bitumen particles. These results bring out a new phenomenon, which may occur when crude oil flows through the porous oil reservoir.

Jan 1, 1942

By Arthur C. Forsyth, R. L. Dowdell

A search through the available literature shows that the cobalt-nickel-silicon system has not been systematically studied. This seems rather odd because all three elements are fairly abundant and have better than average corrosion resistance; however, they have high melting points, which makes experimental work difficult. Cobalt and nickel form a continuous series of solid solutions and each metal dissolves about 7.5 per cent silicon. Many ternary alloys have been studied and the results have been published in a great many different ways, but to present such data in a short but clear and understandable manner is still a problem. The following pages describe the results of the study of 76 alloys from which the partial ternary diagram (Fig. 1) of the cobalt-nickel-silicon system has been drawn. The alloys were chosen according to the plan in Fig. la by taking definite ratios of cobalt and nickel, such as 70 Ni, 30 Co or 40 Ni, 60 Co, and adding silicon in various percentages. Each section was studied in detail by means of thermal analysis and microscopic examination, but only two of these detailed sections were thought necessary in the point perspective drawing to give a comprehensive picture of the liquidus, solidus and solid transformations that take place over the temperature ranges studied. Complete thermal analyses and microscopic data are given in Table 1. Experimental Procedure The alloys were prepared from metals of commercial purity, as follows: electrolytic nickel 99.60 + 0.35 Co; chemically purified silicon 99.79 per cent plus impurities of Fe 0.027, A1 0.008, Ca 0.014, C 0.004, N² 0.10; and cobalt 98.82 per cent plus impurities of Ni 0.42, Fe 0.12, CaO 0.27, S 0.012, Mn 0.10 and SiO² 0.15. It should be noted that the largest impurity in cobalt is nickel, one of the alloying elements. The alloys were melted in a small Ajax induction furnace, the nickel and cobalt being melted first because of their better ferromagnetic

Jan 1, 1940