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By Alex Hay

THE Sydney coal field, the largest and most valuable in Nova Scotia, is situated on the northeastern coast of the Island of Cape Breton, extending from Mira Bay on the south to Cape Dauphin on the north, a distance of 30 miles, and has a general dip northeast under the sea. (Fig. 1.) The field embraces the mining villages of Morien, Birchgrove and Reserve and the towns of Dominion, Glace Bay, Waterford and Sydney Mines. The city of Sydney is situated about midway between the northern and southern extremities of the field and on the western fringe of the productive coal measures. Sydney harbor crosses the coal field, cutting off direct rail connection between Sydney Mines and the greater part of the field to the southeast. (Fig. 2.) The coal measures are exposed in the cliffs on the coast line, which rise to an average height of 30 ft., and are almost continuous throughout the length of the field. The portion of the coal field under land forms a small segment of a circle, the greatest distance from the coast landwards is 9 miles, and it occupies an area of 200 sq. miles. The greatest distance developed seawards from the shore by mining operations is 2 ¼ miles. The strata maintain a regularity of dip at this distance, proving a submarine area of about 70 sq. miles. How much further the coal field extends seawards is unknown, but the indications are that it extends far beyond the present economical working limit and in all probability there is a vast submarine coal field. The productive coal measures are of Carboniferous age, these being underlaid by beds of sandstone, locally classed as millstone grit, which define the southern limit of the field,, while a spur of syenitic hills cuts off the coal-bearing strata on the north. Two main anticlinal folds having a general course easterly divide the field into three basins named from north to south: Sydney Mines-Lingan, Glace Bay and Morien.

Jan 1, 1929

By Hallan N. Marsh, Bruce H. Robinson

It is generally believed that the flowing of wells through tubing instead of casing results in the conservation of gas. It is further believed that use of tubing prolongs the flowing life of a well and results in greater ultimate recovery, provided either that there are no adjacent wells, or that any adjacent wells are similarly operated. Recent experience in the flowing of Buckbee zone wells at Santa Fe Springs has not only substantiated both of these beliefs but has led to the further conclusion that the use of tubing results in a greater cumulative flowing production, ' even in a highly competitive field like Santa Fe Springs, where the wells concerned are closely offset by wells of both the same and other companies flowing through casing. Further, gas-oil ratio has been so reduced that greater ultimate recovery can be expected. In the belief that such would be the case, the majority of the Buckbee zone wells of one company were brought in through tubing, but enough wells were flowed through casing to form the basis for a comparison. For the purpose of this comparison, wells with flow strings 2½ or 3-in. dia. are designated as tubed wells, while those having flow strings larger than 3-in. dia. are designated as untubed wells. Casing used was mostly of 5 ¾-in. dia., the remainder being of 4¾-in. dia. There were 15 tubed wells and 8 untubed wells and they were scattered over the field in such a way that neither group appears to have any distinct advantage as regards location. Locations of all wells involved in the comparison are shown on Fig. 1. All the Buckbee sand wells of the company are included in the average production curves, with the exception of eight that were unsatisfactory for reasons other than the method of flowing. Findings 1. Buckbee sand wells flowing through casing larger than 3 in. had an average maximum production rate of 4670 bbl. per day, while wells flowed through straight tubing or 3-in. casing had an average maximum production of only 3300 bbl. per day. (See Fig. 2.)

Jan 1, 1932

By E. C. W. Perryman

The wide grooves formed at the grain boundaries when high purity aluminum is attacked by hydrochloric acid or sodium hydroxide have been attributed by earlier workers to the high energy of the grain boundary material. The effect has been investigated for high-purity AI-Fe alloys with up to 0.055 pct Fe as a function of iron content and heat treatment. It is shown that the explanation given above is untenable, but that the results can be explained on the assumption that iron segregates to the grain boundary in solid solution. IN 1934, Rohrmann¹ showed that aluminum of 99.95 pct purity suffered intercrystalline corrosion when immersed in 10 to 20 pct hydrochloric acid, and that the susceptibility to intercrystalline corrosion depended upon the heat treatment given. The greatest susceptibility was found for specimens quenched from a high temperature (600°C) and the lowest susceptibility for specimens cooled slowly from that temperature. Lacombe and Yannaquis2 have shown that super-pure aluminum (99.9986 pct) annealed at 600°C suffers intercrystalline attack in 10 pct hydrochloric acid and that this attack is intensified by anodic dissolution in the same solution at a current density of 10 milliamperes per sq dm. No difference in extent of intercrystalline attack was found between the 99.993 and 99.986 pct Al, which led the authors to suggest that impurities played only a secondary role in the mechanism of intercrystalline corrosion. It was found, however, that the attack at the grain boundaries depended upon the relative orientation of the grains, large differences in orientation favoring rapid attack. Boundaries where the two neighboring grains were similarly orientated showed high resistance to attack as did boundaries between grains which were in twin relationship. These observations led Lacombe and Yannaquis to suggest that the intercrystalline attack was due to lattice discontinuities present at grain boundaries. Assuming that the grain boundary is a layer three to five atoms thick and has a crystal structure which is a compromise between the two neighboring grains it is clear that the discontinuities will increase with increasing difference in orientation between the neighboring grains and hence the increasing tendency to intercrystalline attack. Roald and Streicher³ investigated the effect of heat treatment of aluminum alloys ranging in purity from 99.2 to 99.998 pct on the corrosion resistance in 20 pct hydrochloric acid and 0.30N sodium hydroxide. They found that in hydrochloric acid the intercrystalline attack appeared to be determined by the type and quantity of impurities present and by the relative orientation of the grains. No difference in the susceptibility to intercrystalline attack was observed between specimens quenched and those furnace cooled, from 575°C. In 0.30N sodium hydroxide some materials exhibited intercrystalline attack, this taking the form of V-notches. Rohrmann¹ offered no explanation for the greater susceptibility to corrosion of material quenched from 600°C. It seems possible that this difference is connected in some way with a different distribution of impurity elements in the quenched and slowly cooled specimens. The fact that Roald and Streicher8 observed no difference between quenched and slowly cooled specimens may possibly be due to differences in either rate of cooling or silicon content or possibly both. Both these would be expected to have an effect on the distribution of impurity elements. Although the rate of cooling used by Rohrmann was slightly more rapid than that used by Roald and Streicher the position cannot be clarified because Rohrmann does not give the silicon content and Roald and Streicher give the silicon contents of only a few of their alloys. That Lacombe and Yannaquis2 found no difference in corrosion behavior attributable to impurities between the two materials they used may be because both were of high purity compared with the aluminum used by Rohrmann.¹ Although they found no difference in the corrosion behavior of their two materials it is possible that the results obtained by Lacombe and Yannaquis may, nevertheless, have been influenced by impurity distribution, since, on the transition lattice theory of grain boundary structure, it would be expected that sparingly soluble impurities would tend to segregate to boundaries where the orientation difference is such that there is a greater density of atomic sites of suitable size to contain them. It was considered worth while, therefore, to examine the corrosion properties of a series of materials of differing impurity content with the objects of confirming the experimental observations made

Jan 1, 1954

By Thomas E. Garnar

Zirconium and hafnium are curious elements because they are almost always found together in nature. Zirconium was discovered by Klaproth in 1789 and isolated 35 years later by Berzelius. Because hafnium's chemical properties are so close to those of zirconium, it was not discovered until 1923 when Coster and Von-Heresey detected it using x-ray spectrographic analysis. These elements occur most commonly in nature as the mineral zircon (ZrSiO4) and less commonly as the oxide baddeleyite (ZrO2). They also are found as a variety of other silicates. Zircon was identified as a component in alluvial and beach sands in 1895, but it was not produced in any quantity until 20 years later. Zircon is always a coproduct from TiO2 mining and processing. During World War I it was produced as a coproduct of beach sand mining for titanium minerals just south of Jacksonville Beach, FL, and was patented as a refractory. It was not until the 1930s when Zircon Rutile, Ltd. began mining at Byron Bay on the east coast of Australia that zircon was first used as a foundry sand. Later in the 1940s, NL Industries, Humphreys Gold Corp., and E. I. du Pont de Nemours & Co., Inc. began production of zircon sands from fossil beaches in northeast and northcentral Florida. Baddeleyite first became available as a commercial product in 1916, but never in the quantity of zircon. Zircon holds a unique position as an industrial mineral because it is used for both its physical and chemical properties as well as an ore of zirconium and hafnium metals. Australia is the major zircon producer followed by South Africa and the US. Zircon is also produced in India, Sierra Leone, Sri Lanka, Malaysia, China, Thailand, and Brazil. Undeveloped heavy mineral beach sand reserves containing zircon are known to occur in Egypt, Malawi, Senegal, and Tanzania. Locations are shown in Fig. 1. Mineralogy Zirconium and hafnium are always present together in naturally occurring compounds. Most commonly they form as the silicate sometimes containing iron, calcium, sodium, manganese, and other elements. Less commonly they are found as oxides in combination with titanium, thorium, calcium, and iron. Zircon is the most common form. It is extremely resistant to weathering, therefore, often it is present in ancient beach sands and placer deposits. Although resistant to alteration from external sources, it is vulnerable to internal alteration as the result of thorium and uranium substituting for zirconium either in the zircon lattice or in solid solution. Alteration to the metamict state takes place as radioactive emanations from these elements disorder the crystal lattice, accompanied by hydration, reduction in specific gravity, and changes in color. The mineralogy of zircon and baddeleyite and variation of physical and chemical properties are shown in Table 1. The effects of zircon's internal alteration and darkened color can be corrected by heating to 1000°C for 30 min or so. A certain time-temperature relationship makes it possible for decolorization and reordering of the crystal lattice to take place when heating at higher temperatures for shorter periods or at lower temperatures for longer periods. After heating, x-ray diffraction patterns are sharper, the grains may be harder, and except for particles of malacon, the grains will be white or colorless in the absence of grain surface coatings. The color change is only temporary and the particles slowly darken with time. Zircon fluoresces light yellow in shortwave ultraviolet light. If exposed to ultraviolet light for extended periods of time, white (calcined) zircon turns purple. With time the induced color begins to fade and eventually disappears (e.g., calcined Florida zircon exposed to ultraviolet light for 24 hr still retains faint, but discernible, purple color after six months).

Jan 1, 1983

By R. C. Rastogi, F. F. Aplan

The goal of this study is to evaluate the coal flotation process and the interaction of the chemical (reagent) and hydrodynamic (machine, operational) variables as they affect yield, flotation of various sized particles, and sulfur and ash rejection. Coal flotation is found to follow a first order process with the coal floating much faster than either pyrite or ash. This circumstance may be used to achieve gangue rejection during flotation. When floated with MZBC, cresol, or pine oil frothers, coal floats in the size sequence: 108 pm ( - 65 mesh), 589 x 808 pm (88 x 65 mesh), and 1.17 mm x: 589 pm (14 x 18 mesh). However with a substantial amount of fuel oil collector, all particles tend to float roughly in proportion to their content in the feed. An increasing aeration rate was found to be the most important variable in increasing the coal flotation rate. This increase in flotation rate, unfortunately, is also accompanied by an increase in the flotation rate of the pyrite. The rejection of pyrite during coal flotation is best accomplished at low aeration rates, low frother concentrations, and low impeller speeds.

Jan 1, 1986

By J. E. Pogue

It is the purpose of this paper to attempt to establish three theses which may be stated in advance as follows: 1. The crude oil potential is the accumulation of surplus initial production. 2. The crude oil potential is a semi-inventory and therefore is a causal factor in the price of crude petroleum. 3. The price of crude petroleum no longer correlates with above-ground inventories but does correlate with corrected inventories (i. e., above-ground storage plus the inventory equivalent of the crude oil potential). The factors and principles set forth in this study are thought to yield an approximate answer to a number of questions of active interest in the petroleum industry today, to wit: (a) How long would be required to eliminate the potential if all drilling ceased? (b) What would be the indicated crude oil production of the United States in 1931 if proration were abandoned? (c) What economic change would be necessary to warrant a higher price for crude oil? Definitions For the purposes of this study the following definitions may be stated: The crude oil potential in the United States is the quantity of oil that all the oil wells would make the first 24 hr. if permitted to flow unrestricted. The surplus potential is the above-mentioned quantity minus the volume currently produced. Initial production is the first day's unrestricted flow of an oil well. Aggregate initial production is the sum of the initials of all wells completed during a year. Surplus initial is the initial not needed to bring production into balance with demand. The surplus initial is equal to the crude oil potential minus the current rate of production. The annual production-equivalent of the crude oil potential is the volume of oil that would be produced in one year if all wells were permitted

Jan 1, 1931

By Martin Weinstein

A technique is described for preparing finegrained lead telluride by ultrasonic agitation of a solidifying melt. Material prepared by this technique is dense and chemically homogeneous. N-type PbTe, containing 0.03 mole pct PbIz, has been made and its thermoelecCric Properties have been measured as a function of temperature. For comparison, the properties of similarly doped PbTe made by cold pressing and sintering, and by extrusion, have also been measured. The ultrasonically prepared material compares favorably with the others in its thermoelectric-efficiency factor. Comparison of compressive-flow curves for the three kinds of PbTe show that the ulhasonically prepared material has much superior ductility. The cleavage strength of the ultrasonic material is related to the grain size, D, by the Petch relation:Extrapolation to infinite grain diameter yields a fracture strength of 5000 psi for single-crystal PbTe. WHEN metals and semiconductors solidify in a mold they normally assume one of three cast structures illustrated in Fig. 1.' Solidification in a casting starts at the mold walls where a large number of fine crystals of random orientation can be nucleated to form the chill zone. Because of the anisot-ropy of the growth rate, those crystals whose direction of maximum linear growth is parallel to that of the heat flow grow faster and crowd out the crystals of less favorable orientation. A second zone, having a preferred orientation, called the columnar zone, thus forms adjacent to the chill zone. The speed of growth of the columnar grains will depend, in the case of limited undercooling of the melt, on the rate at which heat can be abstracted. The columnar zone can extend to the center of the casting, Fig. l(a), but it is frequently followed, in solid-solution alloys, by another zone of equiaxed randomly oriented grains in the central portion of the casting, Fig. l(b). The equiaxed structure in Fig. l(c) represents the completely grain-refined case where the equiaxed grain size is small. The third type of structure is the most desirable because it imparts a somewhat higher strength for all except high-temperature applications, it reduces segregation of the doping constituent, and it reduces the possibility of hot tearing (the separation of grains due to the melting of a low-melting point constituent in the grain boundaries). In order to obtain fine-grained castings, the nu-cleation frequency must be increased and grain growth must be restricted. Various techniques have been employed for obtaining this end, namely: rapid cooling, vibration, and inoculation of the melt. The success of these techniques depends upon the characteristics of the metal species and on factors controlled by heat transfer through the crucible walls. Recent studies2" have shown that the application of ultrasonic energy to the solidifying ingot is an extremely powerful tool in the improvement of the crystalline structure of metallic castings. Both the mechanical properties and homogeneity of the ingots are improved. Ultrasonic oscillations may affect the crystallization process by 1) permitting subcritical nuclei to agglomerate and thus form nuclei of sufficient size to cause crystallization, 2) changing the state of surface adsorption of various catalysts found in the liquid melt, 3) breaking pieces of solid from the solidified surface near the supercooled region thereby increasing the number of possible nuclei, 4) causing temperature fluctuations to occur in certain parts of the melt thereby increasing the supercooling at specific points in the liquid, and 5) decreasing the critical nucleus size by increasing the pressure at specific points in the melt.' Various investigators have concluded that the effectiveness of the ultrasonic oscillations results from cavitation which disrupts the growing solid-liquid interface The present paper describes the application of ultrasonic oscillations to the crystallization of the semiconductor N-type PbTe. The purpose of this study is to prepare crystalline

Jan 1, 1964

By A. C. Fieldner

In November, 1926, the American Engineering Standards Committee (now the American Standards Association) called a meeting of representatives of various professional societies and industrial, educational and governmental organizations to consider what action, if any, should be taken on the classification of North American coals. This meeting was called because a system for the use classification of coal, proposed by George H. Ashley, had been referred to the committee by the Coal Mining Institute of America. This meeting, at Pittsburgh, was well attended and was definitely in favor of taking up the whole question of scientific and use classification of coals, including all the various ranks from lignite to anthracite. The American Society for Testing Materials was recommended as the sponsor organization to take charge of the work and organize the sectional committee according to the rules of the American Standards Association. The American Society for Testing Materials proceeded with the organization of the sectional committee, holding a meeting in Philadelphia, June 10, 1927. Officers were elected, regulations adopted, and general plans for carrying out the work were outlined. The total membership of 28 comprising the sectional committee consists of 8 producers, 2 distributors, 9 consumers and 9 members representing general and scientific interest. From this committee three technical committees of 10 to 12 members each were organized: Scientific Classification, H. J. Rose, chairman; Use Classification, W. H. Fulweiler, chairman; Marketing Practice, F. R. Wadleigh, chairman. The Technical Committee on Scientific Classification was requested to formulate a system of coal classification based on chemical and physical properties of coal and with reference to origin and constitution. The Technical Committee on Use Classification was charged with developing a system of classification, if possible, based primarily on the uses of coal and commercial practice; this system to be correlated with the scientific system as far as possible and desirable. The Technical Commitlee on Marketing Practice was formed to collect and collate information on commercial practice for the benefit of the other two committees. The first meetings of the technical committees were held on Nov. 17, 1927, and the first informal progress reports were submitted to the

Jan 1, 1930

By F. B. Foley

IT is with an unusual degree of personal satisfaction that I find myself in a position to pay tribute to the memory of Henry Marion Howe. One could not have spent any length of time in the presence of Dr. Howe without profiting intellectually. I do not hesitate to say that my years of association with him were the most stimulating of all my years of metallurgical study. He always impressed one with his own eager search for knowledge. Never dependent on the written word alone he sought information from anyone whose opinion he valued. His ability to piece together bits of apparently conflicting data from various sources so as to build up a logical hypothesis was unique. A small slight man with the intellect of genius he would have gone to the top in any endeavor he undertook and it was fortunate for metallurgy that its study attracted him as it did. Howe was a modest man. I like to recall an incident which left a lasting impression with me. The lab- oratory in his home, "Green Peace," was in the basement and access was by way of stairs leading down from his secretary's room. In using these stairs my attention was attracted many times to an ordinary cardboard shoe box which reposed on the shelf above the landing. It was crudely labeled on its side in black ink "Vanity Box." My curiosity was aroused to the point that I finally asked his secretary what it was. With some amusement she took the box from its shelf on the stairway, opened it and showed me its contents—numerous letters, from the foremost men of science of every civilized country throughout the world, commending his "Metallography of Steel and Cast Iron." I recall that in reply to one who thought there was not enough of Howe's own researches in his book he wrote, "Primarily I am a writer, secondarily an investigator." Howe wrote to make his readers think. No one ever strove harder than he to be right but above all, whether his viewpoint proved ultimately to be right or wrong, he was always content if by his stand, he provoked a reader to take the next step along the path to greater knowledge. I doubt that he was ever afraid to be wrong for he was always secure in the thought that his effort was guided by a sincere search for the truth. One continually searching for truth is entitled to occasional excursions up the wrong alley. A glance backward to the metallurgical confusion of some thirty to forty years ago, or need one go back so far, provides convincing proof of what a host of companions one may have in a common acceptance of ideas which the future will prove to be wholly untenable. Well over a hundred years have passed since investigators have interested themselves in the effect of increasing the temperature of iron and steel on their mechanical properties. We are told by Charles Walrandl in "Industrial Annals" for June 11, 1822, that bend tests, conducted in a Russian steel works of Prince Demidoff, on steel bars "highly heated" and bent during cooling became brittle when bent at an iris blue color. He concluded, "That when steel is heated to a temperature between 473°F and 662°F the mettle was more brittle between these limits than at a much lower or at a much higher temperature." It was a curious bit of information recognized as true to this day and still not explained satisfactorily. In 1878 Charles Houston in Annales de Mines associated this brittleness with an increase in tensile strength at 572°F. When this relatively low temperature is exceeded it is recognized that steel becomes weaker as temperature is increased up to the melting point, where no strength of practical importance remains. It is easy to believe, in fact it goes without saying, that this weakening as the temperature of a metal is increased is the result of the motion of the atoms making up the metal, a motion which itself is evidence of the temperature increase. However, if we are considering iron or steel we find that this decrease in strength is not a steady one, for, besides the increase in strength just referred to, one comes to a temperature, the critical temperature, where results of tests indicate the metal to be extremely weak and then as temperature increases to become sensibly stronger again. This apparent anomaly was made the subject of the first Howe Memorial Lecture, delivered by Albert Sauveur in 1924. It may be of interest to review these findings of Sauveur. He used two methods of investigation. One involved the twisting of bars. The bars were heated in an

Jan 1, 1951

By C. H. Mathewson, W. R. Hibbard, Robert Maddin

A satisfactory mathematical relationship between shear, elongation and change of orientation in the axial straining of a single crystalline rod or wire may be based on a simple model in which blocks, representing glide lamellae, glide over one another and rotate so as to maintain the original fixed position of the axis as the wire elongates.' Obviously such a model gives no information concerning strain-hardening or the atomic adjustments at the sliding surfaces and their influence on the internal structure of the blocks. Moreover such an operation could be conducted with rigid blocks only by using self-aligning grips or a flexible attachment which would permit the adjacent blocks to freely assume their changing orientations. There are many unsolved problems (see Andrade2) concerning the manner in which nature departs from the simple model in permitting the essentials of slip, rotation and elongation to occur along with strain-hardening and the appearance of glide lamellae of various dimensions and special characteristics, not fully appreciated at the present time. This paper describes part of an extensive investigation on the development and characteristics of glide ellipses in single crystalline alpha brass rods and is especially concerned with the observation of cross-slip in crystals oriented wholly within the range of slip on a single system according to the generalizations first presented by Taylor and Elam in 1923.³ Experimental Procedure Half-inch rods of alpha brass (nominally 70 pet Cu, 30 pet Zn)* were converted into single crystals by melting and gradual solidification in a graphite mold according to the Bridgman method.4 In order to remove any coring, the crystals were homogenized at 800°C for 16 hr and tested by etching with a 50 pet nitric acid solution. The back-reflection Laue technique as described by Greninger6 was used for determining the orientations of the crystals. Standard stereographic operations were employed to locate the specimen axis in a triangle of the Taylor and Elam3 projection so that the slip plane and direction could be predicted. The lineage structure reported by Buer-ger6 was present in the crystals used in this investigation. However, only crystals were used in which the internal differences in orientation did not exceed two degrees. Very little is known concerning the effect of the presence of a lineage structure on the detailed mechanism of plastic deformation.

Jan 1, 1949

By C. H. Mathewson, Robert Maddin, W. R. Hibbard

A satisfactory mathematical relationship between shear, elongation and change of orientation in the axial straining of a single crystalline rod or wire may be based on a simple model in which blocks, representing glide lamellae, glide over one another and rotate so as to maintain the original fixed position of the axis as the wire elongates.' Obviously such a model gives no information concerning strain-hardening or the atomic adjustments at the sliding surfaces and their influence on the internal structure of the blocks. Moreover such an operation could be conducted with rigid blocks only by using self-aligning grips or a flexible attachment which would permit the adjacent blocks to freely assume their changing orientations. There are many unsolved problems (see Andrade2) concerning the manner in which nature departs from the simple model in permitting the essentials of slip, rotation and elongation to occur along with strain-hardening and the appearance of glide lamellae of various dimensions and special characteristics, not fully appreciated at the present time. This paper describes part of an extensive investigation on the development and characteristics of glide ellipses in single crystalline alpha brass rods and is especially concerned with the observation of cross-slip in crystals oriented wholly within the range of slip on a single system according to the generalizations first presented by Taylor and Elam in 1923.³ Experimental Procedure Half-inch rods of alpha brass (nominally 70 pet Cu, 30 pet Zn)* were converted into single crystals by melting and gradual solidification in a graphite mold according to the Bridgman method.4 In order to remove any coring, the crystals were homogenized at 800°C for 16 hr and tested by etching with a 50 pet nitric acid solution. The back-reflection Laue technique as described by Greninger6 was used for determining the orientations of the crystals. Standard stereographic operations were employed to locate the specimen axis in a triangle of the Taylor and Elam3 projection so that the slip plane and direction could be predicted. The lineage structure reported by Buer-ger6 was present in the crystals used in this investigation. However, only crystals were used in which the internal differences in orientation did not exceed two degrees. Very little is known concerning the effect of the presence of a lineage structure on the detailed mechanism of plastic deformation.

Jan 1, 1949

By T. F. Witherbee

The following calculation of heat requirement covers the working of the furnace from January 25th to February 14th, inclusive. A short time previous to the first date the furnace had been working rather badly, so that 300 lbs. of ore and 500 lbs. of limestone were taken off. Within the time mentioned the quality of the iron passed

During the year Jan. 1 to Dec. 31, 1916, 962 applications for member-ship in the Institute were received, as compared to 558 during the corresponding period in 1915. The lines along which the Committee has, worked during the year, group themselves under seven principal heads. Large Companies.-Early in the year a letter was addressed to each member of the Institute who is the executive head of an organization, pointing out to him the advantages that would accrue to that organization through having as many of its subordinate members as were qualified participating in the activities of the Institute. This was followed by a second letter to those who made no reply to the first. The response to these letters was very gratifying, 12 new members having been secured at a single plant, and smaller numbers at others. This was effectively supplemented by our President, who wrote the executive heads of some of the largest mining and smelting companies, pointing out to them the advantage to be derived from sending some of the junior members of their staff to attend the Arizona Meeting. One organization sent 24 of its younger men, many of whom were not members of the Institute, but who, subsequently sent in applications for membership. It is to be hoped that the precedent thus set' will be acted 'on in -fuller measure in succeeding years.

Jan 2, 1917

By Alfredo O. Del Campo

Copper concentrate smelting has been the subject of significant improvements during the last three decades. Several new processes are being successfully applied at industrial scale, and probably no new copper smelter will be built with the old-fashioned reverberatory furnace. However, because of financial reasons, the existing reverberatory furnaces, which smelt a significant part of the copper produced worldwide, are likely to last at least another decade. Some improvements have been introduced in reverberatory smelting practice, the best known being the use of oxyfuel burners. However, efforts to optimize the reverberatory furnace operation through automatic control have not been reported. The complex and semi-continuous nature of the process makes it dificult to find a suitable strategy for its automatic control. Many factors, like fuel economy, productivity, boiler capacity, refractory wear, converter slag return, copper losses in discard slag, etc. are interconnected. The chosen control strategy should take into account all these factors to achieve good economic results. A detailed discussion of these problems is presented.

Jan 1, 1984

By Magnus Troilius

The following is a very rapid method for determining copper in steel. I have found it to give results very closely agreeing with those obtained by galvanic precipitation of the copper. Five grams of steel are dissolved in a mixture of 100 C.C. of water and 10 C.C. of sulphuric acid. When all is dissolved, add 2 C.C.

Jan 1, 1883

By Albert E. Wiggin, Frederick Laist

Early ill 1914 it was decided to test, on a fairly large scale, the treatment by flotation of Anaconda slime and mill tailing. For this purpose a standard-type Minerals Separation machine was installed at the Washoe Reduction Works during May and June, 1914. This was followed by the installation of a full-size Callow pneumatic machine plant. Experiments were also made, on a smaller scale, with the Froment, the Towne, the Fields, and the Anaconda flotation machines. The last-named machine was developed at this plant. In addition to the tests made in the standard-type Minerals Separation machine some tests were made using a Minerals Separation machine of the sub-aeration type. During the series of experiments a large variety of oils was tested. Experiments were also conducted using both round-table feed and tailing to determine whether it would be better to displace the round tables by flotation for the treatment of the slime, or to supplement the round tables by flotation of the round-table tailing. A series of tests was also made on the treatment of the mill tailing by grinding followed by flotation to determine the relative merits of flotation and leaching for the treatment of this product. In addition, flotation tests were made on mixtures of mill tailing and slime. The round-table feed referred to above is the total slime from the mill. It contains about 35 per cent. colloidal solids and approximately 90 to 95 per cent. of the total solids will pass through 200 mesh (0.067 mm.). It assays from 2.3 to 2.6 per cent. Cu. The mill tailing referred to above is the total discard from the mill, exclusive of the slime. It is all finer than 2 mm. and about 90 to 95 per cent. will remain on 0.25 mm. It assays about 0.60 per cent. Cu. A brief summary of the experimental flotation results follows:

Jan 1, 1917

By A. E. Wheeler, H. Y. Eagle

The copper industry in the Province of Katanga, in the Belgian Congo, which is now controlled and operated by the Union Minére du Haut Katanga, had its inception many years ago in the vision of a Scotsman, Robert Williams, now Sir Robert Williams, Baronet. He it was who personally negotiated the mineral concession with King Leopold of Belgium, sent in the prospecting parties who located most of the present mines of the company, later arranged for the Belgian participation from which the present company was formed, and has been its active mentor ever since. The idea back of his efforts was the establishment of an industry on the Congo-Zambezi divide, of sufficient importance to draw up to it the head of the Cape to Cairo Railroad, the dream of Sir Cecil Rhodes, and the consummation of which he had left as a legacy to Mr. Williams, his successor. The reports of the prospecting expeditions showed that copper in profitable quantity was there, but many difficulties lay in the way of the establishment of the infant industry. The isolated location of the mines, various tribal wars, the Boer War, and many other factors contributed to making progress very slow. However, in spite of these difficulties the railroad was finally built and a blast-furnace plant erected at Lubumbashi, near Elisabethville, the capital of the Province. Operations of this plant were started in 1911, treating high-grade oxidized ores and producing pig copper by a reducing smelting. Production has been continuous since that time and the company has grown so that at present it ranks as the largest individual copper producer in the industry. It is a fitting monument to the foresight, optimism and driving force of its founder, and the progressive policies of his Belgian colleagues. In January, 1914, the Union Miniere du Haut Katanga engaged as its consulting engineer, Archer E. Wheeler, metallurgical engineer, at that time general superintendent of the Great Falls plant of the Anaconda Copper Mining Co. Mr. Wheeler was commissioned by the Board of Directors to proceed into Katanga, and make all necessary investigations to enable him to report on a comprehensive development program, and to recommend a scheme of treatment particularly for their low grade

Jan 1, 1934

By C. E. Birchenall, G. Derge

IN studying the kinetics of slag-metal reactions, it has become increasingly apparent that a complete knowledge of all aspects of interface phenomena will be required to clarify these processes adequately. A part of the data required for all oxidizing slags used in the refining of impure iron to steel is the rate of exchange of iron between the slag and metal phases. The simplest equilibrium of this type is that between liquid iron and iron silicate slag when both phases are equilibrated with the silica crucible containing them. In this study, the exchange of iron between the two liquid phases has been measured by using radioactive Fe as tracer. The observed high exchange rate indicates the ease with which such interfaces may be crossed in refining processes. The experiments required for this study involved relatively minor and normal modifications of well established techniques. Melting was accomplished by induction heating in heavy walled, fused silica, rotating crucibles." Rotation was used to minimize dilution of the slag by crucible erosion. The melting stock was ingot iron. Slags were prefused in iron crucibles using chemically pure grade oxide reagents. The special conditions applying to the active iron additions will be described for individual experiments. Suitable precautions were observed with regard to protection against radiation hazards.' Identification of Activity This particular study was initiated several years ago, but held in abeyance because the radioactive iron available at that time contained a foreign activity which concentrated in the slag so as to mask the iron activity and render the results unin-terpretable. With the benefit of experiences from other studies, radioiron of suitable purity can now be prepared. As received from the Isotope Div. of A.E.C., the unit appears to contain Fe + Fe50 and a high activity cobalt. The cobalt and iron are separated by repeated ether extractions, and the purified iron stored for sufficient time for the Fe'7 44 day half-life) to decay to negligible activity, leaving only Fe as the active isotope. This was confirmed by the absorption curves for slag and metal samples from heat No. 1. In Fig. 1 the experimentally measured points for the absorption curves of slag and metal are fitted by the calculated slope of 5.8 mg per sq cm in aluminum, which corresponds to the Mn K doublet emission resulting from the capture of an orbital electron of Fe" by the nucleus. This shows that the radioactive species are the same in both slag and metal and identifies it as Fe55 Description of Individual Heats For the first heat, the radioactive iron was contained in the prefused slag. The active Fe55 had been precipitated with carrier and was added as Fe2O3 during fusion in the iron crucible. The charge of 500 grams of ingot iron was melted, the protective iron sleeve added, rotation started, and a prefused, inactive slag was added to allow the system to approach equilibrium. After about 5 min at temperature, the wash slag was skimmed and the active slag added. Initial slag and metal samples were taken as soon as the slag was molten. Additional samples were taken at indicated intervals thereafter. Slag samples were dipped with a small iron spoon and metal samples were sucked into 1/4 in. ID silica tubes. The slag and metal samples were pulverized and mounted for radioactive counting. The slag samples were analyzed chemically for FeO. Temperature was read after the last slag sample by immersion of a Pt-Pt-Rh thermocouple protected by a fused silica sheath. Since no significant variation of rate with temperature was observed

Jan 1, 1954

By H. W. McCue, Henry Rogatz

Oil.—In the Texas Panhandle, during the year of 1941, 647 oil wells were drilled with a total daily initial production of 133,435 bb1.—that is, 145 more oil wells than in the previous year, with a decrease in total daily production of 5752 bbl. On Dec. 31, 1941, a daily allowable of 116,766 bbl., which was an increase of 27 per cent over 1940, was assigned to the field to be produced from 5182 wells. The total amount of oil produced for the year was 27,904,846 bbl., making a cumulative total of 404,657,324 bbl. during the past 20 years. Gas.—During the year, 52 gas wells were drilled, having a combined open flow of 2.62 billion cu. ft. per day—that is, 40 less than the number of wells drilled in 1940, with an increase in the open flow of 217,100,000 cu. ft. per day. The gas

Jan 1, 1942

By Henry Rogatz, H. W. McCue

Oil.—In the Texas Panhandle, during the year of 1941, 647 oil wells were drilled with a total daily initial production of 133,435 bb1.—that is, 145 more oil wells than in the previous year, with a decrease in total daily production of 5752 bbl. On Dec. 31, 1941, a daily allowable of 116,766 bbl., which was an increase of 27 per cent over 1940, was assigned to the field to be produced from 5182 wells. The total amount of oil produced for the year was 27,904,846 bbl., making a cumulative total of 404,657,324 bbl. during the past 20 years. Gas.—During the year, 52 gas wells were drilled, having a combined open flow of 2.62 billion cu. ft. per day—that is, 40 less than the number of wells drilled in 1940, with an increase in the open flow of 217,100,000 cu. ft. per day. The gas

Jan 1, 1942