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By D. D. Smith, D. P. Squier, E. L. Dougherty

A system of differential equations describing the temperature behavior of fluid injected at constant surface temperature in a well is derived and .solved analytically. A formula for the fluid temperature at any time and depth is given, as well us a special formula valid for very large times. These formulas are used to calculate temperatures for several typical cases. The results indicate that, initially, the temperature of the water entering the formation is considerably lower than the injection temperature. This condition lasts for only a short period— less than three days for most cases of practical interest. Following this highly transient period, during which the temperature of the fluid entering the formation builds up to about 50 to 75 per cent of the injection temperature. the system enters a quasi-steady state in which the temperature changes are very slow. After severl years, the bottom-hole temperature will still be 50" to 100°F lower than the injection temperature, hilt the heat losses may he tolerable. INTRODUCTION Predicting the behavior of a hot-water flood requires that the temperature of the water entering the injection interval be estimated. This report describes the development and solution of a system of equations which describes the temperature behavior of the injected water in the wellbore with certain simplifying assumptions. The only previous means known to the authors for describing such a process is that of Moss and White.' Their results appear to be close to those obtained by our method in the practical cases which were compared; this agreement is largely due to the fact that in our method temperature soon approaches a quasi-steady state, as was assumed in their method throughout. However, our model covers all times, is continuous (whereas the Moss-White model depends on breaking the depth into discrete intervals) and. we feel. more closely describes the physical problem. FORMULATION OF THE PROBLEM PHYSICAL SYSTEM AND ASSUMPTIONS The injection procedure consists of pumping water at a fixed surface temperature T., down an infinitely long cylindrical well or tubing of inner radius Any material exterior to the water column such as mud, casing, or cement is regarded as part of the formation. The general behavior of the system may be described qualitatively as follows. When the hot water is first introduced into the system, the temperature difference between the formation and the water is large, resulting in a high rate of heat transfer. As a result, the temperature adjacent to the wellbore rises very quickly. Because the segment of the formation adjacent to the wellbore largely controls the heat transfer rate, the heat transfer rate will become relatively constant when this portion has reached a temperature close to that of the water opposite it. The temperature of the water and formation then increase very slowly with time. The length of the initial highly transient period and the temperature of the water at its conclusion will be functions of depth, injection rate, injection-string radius, surface injection temperature and the physical properties associated with the water-formation system. The following additional assumptions were made. 1. There is no heat transfer by radiation in the system. 2. There is no heat transfer by conduction in the vertical direction in either the injection stream or the formation. 3. The linear volumetric and mass flow rate of the water is constant throughout the injection stream. 4. No horizontal temperature gradient exists in the injection stream. 5. The product of density and heat capacity is constant for both the water and the formation, and the formation thermal conductivity is constant. 6. Initially, both the water in the wellbore and the reservoir are at a temperature given by the (constant) ambient surface temperature plus the product of depth and geothermal gradient (assumed constant). At large distances for the wellbore (r m), the formation will remain at this temperature. 7. The water temperature and the formation temperature at r — r,, are equal for all depths D. DERIVATION OF EQUATIONS The differential equation satisfied by the fluid temperature T,(D, t), which is obtained by writing a heat balance on a cylindrical differential of volume dV of the injection string between the depths D and D i dD, is

By Paul G. Shewmon

The migration of slightly solzrhle spherical particles through a solid under the infllrence of a temperature gradient is analylzed for the cases of various transport mechanisms. It is shown that the variation of the velocity of the particles with radius, r, depends on the dominant mechanism of matter transport around or through the inclusion. Thus the velocity varies as r-1 jor surface-dijf1~sion controlled migratzon. is independent of r for volume diffusion in either phase, and varies as if the rate is determined by an interfacial reaction (n is the order of the interfacia1 reaction). These same results hold tor the migration of a cvlinder of length much greater than its radius. and .for other types of potential gradients, e.g., an electrical field. These equations are combined with recent electron-microscopic ohservations to show that the rate of migratzolz of small helium-silled bubbles through copper is determined by surface diffusion of the metal atoms. With these equations and the temperature gradients attainahle in an electron-microscope joil, the dominant transpar/ mechanism (or any migrating pnrtzclos can he determined. AS a result of fission, rare-gas atoms are created in the hot fuel element of a nuclear reactor. These insoluble atoms precipitate to form bubbles of the gas in the fuel. The subsequent migration and coalescence of these bubbles is thought to play a dominant role in the swelling of fuel elements which in turn can limit the fuel-element life. As a result of this practical problem and because of the relative simplicity of the system, workers in several laboratories have imbedded rare-gas atoms in metals with the aid of an accelerator and studied the formation and behavior of the bubbles that form on annealing. Recently Barnes and Mazey have studied the migration of such helium-filled bubbles in copper foils using the electron microscope and the temperature gradient that can be induced in the foil by the electron beam. They found that the smaller bubbles moved faster than the larger ones. It is shown below that, if this is true, the rate-controlling step in their migration is surface diffusion of metal atoms instead of volume diffusion, vapor transport, or an interfacial reaction. The analysis given is in no way limited to gaseous inclusions so the variation of velocity with particle size for any relatively insoluble precipitate particles could be used to obtain information about the relative importance of surface diffusion, volume diffusion, and interfacial reaction in such two-phase systems. VOID MIGRATION IN A TEMPERATURE-GRADIENT ANALYSIS Barnes' studies indicate that helium does not dissolve or diffuse in metals to a measurable extent, so that when the voids move they must do so through the movement of metal atoms from the leading to the trailing sides of the void.' Thus voids might move by surface diffusion, diffusion of vacancies in the surrounding lattice, or vapor transport. We consider first the case of flow by surface diffusion alone. We assume that there is a force, in the sense of irreversible thermodynamics, tending to move the atoms around the bubble in a given direction. We designate this direction as the x axis and the force per atom as Fa. The net rate of flow of atoms from one side of the bubble to the other, under the influence of this force, is the surface flux, Js, times the cross-sectional area available for flow, A,. A, is taken as the circumference times the thickness of the high-diffusivity surface layer 6. Thus where 51 is the atomic volume. For bubbles to advance a distance dx, a volume equal to nr : dx must flow around the void so that The minus sign enters because the bubble moves in the direction opposite to that of the force on the atoms. Equations for volume diffusion and diffusion through the vapor can be obtained in the same manner. For vapor transport we have Ag = and the ratio of the densities of metal atoms in the gas and the solid (pg/pl) enters so that

Jan 1, 1964

By Milton R. Pickus, Earl R. Parker

THE modern theories of creep¹-4 in general have been based upon the concept of generation and migration of dislocations, with the generation process normally assumed to be rate controlling. The theories are generally deficient in that they fail to take into account many factors that are known to influence creep. The influence of the state of the surface of the test specimen has been almost completely overlooked; yet the present report shows that the nature of the surface may, in certain cases, govern the creep characteristics of a specimen. In the period since Taylor" applied the concept of dislocations to a study of metals, a school of thought has developed that closely relates the plastic deformation of metals to the generation and migration of dislocations through the crystal lattice. It might be expected that the thermal energy required for the generation of a dislocation would be different from that for migration of the dislocation through the lattice. Furthermore, the activation energy for generation would be expected to vary for different parts of the solid metal. It has been predicted that dislocations would be generated most easily at external surfaces, but could also be activated at certain internal surfaces such as grain or phase boundaries. Within the body of the metal a range of values for the activation energy might be expected because of different degrees of disorder at such regions as grain boundaries, impurities, and second-phase particles. The particular value of the activation energy that was rate determining could then depend on the specific conditions of a test. If, for example, the surface atoms were by some means constrained, the generation of dislocations in the body of the metal might become the important factor. On the other hand, other conditions may favor generation at the surface. It is possible then that the creep behavior may not be completely determined by the inherent properties of the metal. Even the environment in which a test is carried out could have a significant effect. In fact it is conceivable that in order to obtain the maximum creep resistance from a given alloy, the surface atoms must be so constrained that the activation energy for generating dislocations on the surface is at least equal to that required for generation in the body of the metal. On the basis of such considerations, and in view of the limited number of publications discussing this subject, it seemed that an investigation of the influence of the state of the surface on creep might yield information of both theoretical and engineering interest. Experiments on single crystals, demonstrating a variation in the mechanical properties due to alterations in the surface layer, have been reported by several investigators.6-13 he results of these experiments have been briefly summarized;14 consequently, the earlier work will not be reviewed here. As an example of these findings the observations of Cottrell and Gibbons may be cited. They reported the critical shear stress of a lightly oxidized cadmium single crystal is greater by a factor of 2½ than a specimen with a clean surface. Materials and Methods Single crystals M in. in diam and 8 in. long were prepared from Horse Head Special zinc, melted under an atmosphere of helium in a large pyrex test tube, and drawn up into a long ½ in. diam pyrex tube by means of a vacuum pump. The cast zinc rods thus produced were cut into convenient lengths and sealed in evacuated pyrex tubes. Single crystals were grown by gradual solidification of the remelted rods. Cleaving the ends of the single crystal specimens chilled by liquid nitrogen proved a simple method for determining orientations from the exposed basal plane from the markings left on the cleaved surface that gave the slip directions with sufficient accuracy for the experimental work. The specimens chosen for the experiments were those having the angle between the basal plane and the specimen axis within the range of 15" to 65". Since zinc single crystals are quite delicate, it was necessary to devise an appropriate method of gripping the specimens in order to suspend them in the furnace and apply the load. Stainless steel collars were prepared having an inside taper, the smaller end of the taper being of such a size that the specimen could just pass through freely. The tapered hole did not extend the full length of the collar; a sufficient thickness of metal remained so that a hook could be attached to provide a means of applying the load and suspending the specimen. One of the collars was slipped over the upper end of a specimen which was supported vertically in a steel jig. The collar was then heated electrically until the end of the crystal melted and filled the collar with molten zinc. At this point the application of heat was discontinued, whereupon the molten zinc quickly solidified, due to the chilling effect of the jig. The specimen was then inverted and the second collar applied in a similar manner. The jig served several purposes: limiting the length of specimen that was melted, providing excellent alignment of the collars with respect to the specimen axis, and protecting the specimen from mechanical damage. Once the specimen was suspended in the furnace and loaded, it was desired to accomplish the surface treatment with a minimum of disturbance of the specimen. Around the specimen was a long pyrex tube, the upper portion of which was approximately 1 in. in diam, and in it was a copper coil of such a diameter to fit snugly against the tube. A specimen, approximately ½ in. in diam and 4 in. long, was suspended by means of a stainless steel rod so that it hung within the copper coil. The lower portion of the glass tube was approximately ¼ in. in diarn, and passing through it was a 5/32 in. diam stainless steel rod which hung from the lower specimen collar. This portion of the glass tube and the stainless steel rod extended through the bottom of the furnace. A T-connector, with suitable packing, was attached to the lower end of the stainless rod to provide a water-

Jan 1, 1952

Jan 1, 1958

Allan Gibb, Queensland, Australia (communication to the Secretary*):—It is gratifying that Mr. Edward Keller,' who has clone so much work elucidating the principles of copper-metnllurgy, should have subjected only that portion of our investigation relating to magnetic iron oxide to anything like adverse criticism. Situated as we were on a rnining-camp, it was impossible to undertake work that would cover all the intricate possibilities connected with the materials commonly classed as matte. We therefore began the investigation on matte produced from ores that contained no other components than the sulphides of copper and iron that would be likely to enter into the composition of matte. We were, accordingly, free from ally possibility of magnetic iron oxide entering the matte, unless it were formed in the operation itself. The work done on this subject was incomplete, and the results thereof recorded as giving only negative evidence as to the absence of magnetic iron oxide. It would have been better to have left the matter open, as " not proven." The trend of the investigation was to account for the insufficiency of sulphur in matte to satisfy the requirements of ferrous and cuprous sulphides. So far as our deductions are correct, it was unnecessary to consider the (in our samples) somewhat doubtful constituent, magnetic iron oxide. The mattes that mere investigated were among those mentioned by Mr. Keller, " which scarcely show ally magnetic property." The samples showed no such property. There was no unaccountable variation in the specific gravity, which only varied, as would be expected, with the proportion of ferrous sulphide. I have had experience in smelting ores of which the gangue was a siliceous magnetite, both in blast- and rever-beratory furuace. The mattes so produced contained magnetic

Jan 1, 1908

By Orville R. Lyons

THE removal of moisture from coal has been a coal-preparation problem ever since the first wet-washing preparation plant was placed in operation. Today, when most of the coal produced in the United States is wetted at the working face when mined, or is cleaned by wet methods, the removal of moisture is a necessity for any one or a combination of the following reasons; (1) to avoid freezing difficulties during shipment, (2) to increase the B.t.u. content, (3) to effect savings in freight costs, and (4) to so improve the coal that it may be used for specific purposes-for instance, in the production of briquettes or the production of metallurgical coke-or so that it can be treated by dry cleaning methods. In general, the amount of water retained by coal particles varies with the size-consist of the coal. Fine coal has a larger surface area per unit weight than does coarse coal, so its capacity for retaining moisture is proportionately greater. The removal of moisture from coarse coal is relatively easy, while the removal of water from minus 10-mesh coal or finer is a major problem, usually requiring an individual solution at each preparation plant. As a result, a multitude of methods and a variety of equipment have been designed to solve both general and specific moisture-removal problems. Definitions In order that misunderstanding may be eliminated insofar as possible, it is necessary to define the terms to be used. The moisture content of any given increment of wet, washed coal is made up of two parts, inherent and surface moisture. Inherent moisture has been defined in various ways and as yet no standard definition has been agreed upon. However, in general, it is considered as the moisture that is present in the coal in the bed. The important point to remember is that coal with any amount of inherent moisture, whether 2 or 20 per cent, will appear dry if there is no surface moisture. Also important is the fact that inherent moisture can be removed, in part, by air drying at atmospheric temperatures. Surface moisture is that attached to the surface of the coal particles or that retained in cracks and fissures other than capillary openings in the coal substance. Essentially, insofar as the bituminous coal and anthracite indus-

Jan 1, 1950

By William Y. Holland, Roger H. Cook

Dexter H. Reynolds (Chapman and Wood, Mining Engineers and Consulting Geologists, Albuquerque, N. M.)—A number of questions are raised by conclusions and inferences made in the above-mentioned paper. The more troublesome of these concern use of the various pozzolans to combat the deleterious effects of the alkali-aggregate reaction. The most alkali-reactive materials listed are opal and rocks containing opaline silica. The pozzolans mentioned specifically for use as amelioratives are opaline shales and cherts. These are stated to retard the expansion caused by the alkali-aggregate reaction. Another well-recognized pozzolan is diatomaceous earth, which consists principally of opaline silica. A pozzolan presumably owes its effectiveness to its high reactivity with the alkaline liquid phase of the concrete mix. It appears reasonable to expect that finely divided opaline silica added as a pozzolan would be more susceptible to reaction with the alkalies present than would larger particles of the same material. The authors report that work with high and low alkali cements indicates that in the presence of alkali-reactive materials, deleterious expansion depends upon the alkali content of the cement. The total effect, therefore, should be more or less independent of the amount of reactive aggregate present, and still more independent of its state of subdivision. The deleterious effects should, if anything, be aggravated by the addition of a finely divided, highly reactive pozzolan. Further, if the alkali-aggregate reaction is of great importance in the long-term soundness of concrete structures, the addition of a pozzolan to a concrete made with aggregate free from known deleterious materials would be a questionable procedure. The benefits reportedly accruing from such use of pozzolans are greater ultimate strength for a given cement content, increased resistance to deterioration by exposure to sulphate solutions and other mineral waters, and greater resistance to damage by wetting and drying and freezing and thawing. In view of the deleterious effects of highly reactive materials are these benefits ephemeral? The same considerations apply to another alkali-reactive material, chalcedony, which appears to consist of ultrafine-grained quartz, with opal absent in detectable amounts. Quartz flour is notably reactive chemically and physiologically (cf. Ref. 11 of Holland and Cook's paper), a fact borne out by its effectiveness as a pozzolan, which presumably might be expected to offset the deleterious effects of the presence of chalcedony in the aggregate. A second question of some importance concerns the reportedly highly deleterious reactivity of acidic and intermediate volcanic glasses, such as rhyolite, perlite, and pumice. Air entrainment is listed as one of the ameliorative measures to combat the deleterious effects of the alkali-aggregate reaction. The alkalic-silica gel formed by the reaction may expand into air bubbles and thus not cause appreciable expansion of the concrete mass. It would appear then that pumice and perlite, particularly perlites of the pumiceous types and other types after expansion, would also tend to counteract the expansion, since these materials consist largely of voids and air bubbles. Certainly this would be expected of structural concrete in which pumice or perlite is used as total aggregate. Finely ground pumice, perlite, and volcanic ash have been demonstrated to be active pozzolans (cf. Pumice as Aggregate for Lightweight Structural Concrete by Wagner, Gay, and Reynolds, Univ. of New Mexico Publications in Engineering No. 5, Albuquerque, 1950). In fact, the term pozzolan was first associated with finely divided pumice or volcanic ash. Such materials were used with hydrated lime as the sole cementitious agent in constructing public buildings, roads, and aqueducts by the ancient Romans. The deleterious alkali reactivity of the volcanic glass, itself containing several percent of the alkalies, apparently did not contribute to the remarkable state of preservation of those ancient structures, as exemplified by the Appian Way and the Pantheon Dome. Still a third question involves .the reactivity of constituents of concrete when exposed to various salt solutions. Resistance to. deleterious expansion and cracking as a result of contact with mineral waters and its relationship to the mineral content of the aggregate are not mentioned by the authors. Yet the phenomena pictured in Fig. 1, and especially in Fig. 2, appear very much like those caused by exposure to mineral waters. The deterioration of concretes exposed to sulphate waters is generally considered related to the chemical constituency of the cement itself, particularly to the relative amount of tricalcium alum-inate contained. Could not many of the ill effects presently blamed on alkali-aggregate reaction really have been caused by contact with sulphate or other salt-containing mineral waters? Or perhaps their use as mixing waters? May not the deleterious expansion be as much a function of the chemical makeup of the cement as it is of the mineral constituency of the aggregate? Would it not be just as important to use alkali-free mixing water as it is to use a low-alkali cement? It appears obvious that resistance of cements and concretes to sulphate and other salt solutions cannot be left out of account in discussion of deterioration of concrete structures with time. This factor may be of equal or even greater importance than the alkali-aggregate reaction, particularly for concrete subjected to wetting and drying cycles, such as airstrip paving, water-retaining dams, and highway structures. Another very important factor is called to attention on page 1022 of the article in Mining Engineering, October 1953, in that failure of concrete structures may result from poor construction practices and use of too high water-cement ratios. Both of these can contribute remarkably to decreased resistance to attack by sulphate waters, and presumably could have an equally remarkable effect upon extent of damage resulting from the alkali-aggregate reaction. From the above remarks it appears that while alkali-aggregate reaction may be an important factor in decreasing the useful. life of a concrete structure, it is not the only factor involved, and it may not be even a controlling factor. Likewise, many of the phenomena apparently associated with the alkali-aggregate reaction may have resulted from cond'itions which had little relationship to the alkali-reactivity of a constituent of the aggregate. Certainly if alkali-aggregate reactivity is a major factor in bringing about early failure, one cannot help feeling anxiety concerning the future of the many concrete structures in this country and abroad in which pumice and perlite were used as total or partial aggregates. This anxiety can only be dispelled by calling to mind that among the best-preserved relics coming down to us from ancient times are structures made with mortars containing highly alkali-reactive aggregates.

Jan 1, 1955

By D. Murgue

The circulation of air in underground workings is subject to a gradual and continuous reduction of its pressure, from intake to outlet, caused by the friction between it and the more or less rough and uneven surfaces of the passages. For comparison with the flow

Jan 1, 1894

By W. E. D. Stokes

THE application of aviation to mining and petroleum operations, on the basis of economy and attainment, has become a demonstrated fact. According to Dominion Government records, 30 Canadian companies engaged in air transportation with northland mining camps, carried 13,000 tons of freight in 1935, and in 1936 carried 16,000 tons. In addition, many mining companies used planes to transport prospectors with canoes, outboard motors, gasoline drums and supplies to remote locations, and one company maintained a plane to take radium-bearing ore from its mine on Great Bear Lake nearly 1000 miles south to the rail- way at Waterways, Alberta. Heavy pieces of mining machinery weighing 2 tons are being carried by Ford trimotor planes over the Andes, at an altitude of not less than 15,000 feet. At Bulolo, New Guinea, 17,500 tons of disassembled gold-dredging equipment has been flown over inaccessible terrain, while supplies and building materials for a community of 1000 whites have been transported by airplane. A 3 1/2-ton shaft was carried on one notable trip, while at another time an automobile, 2 tons of rice and a large safe went over the mountains in one plane. Fig. 1 shows an electric generator that was carried by plane to Bulolo. Many large American oil companies operated fleets of planes during 1936, ranging from fast, luxurious air liners for executives to elaborate geological prospecting units, ambulance planes, freight carriers and pipe-line repair crews. According to the U. S. Geological Survey, commercial firms photographed 16,291 square miles during 1935, while the Government compiled from aerial photographs by the Geological Survey in the United States 85,544 square miles. It was found that information could be determined in a fraction of the time required by surface methods. However, sounding a word of caution, a Commonwealth of Australia government report on aerial survey operations had this to say: It is necessary to repeat ad nauseam that aerial photographic survey is in no sense a substitute for geological investigation, though it is a very valuable adjunct thereto, and greatly facilitates and accelerates geological mapping. There are many details

Jan 1, 1937

By H. H. Stoek, G. W. Harries

The term " Anthracite Coal-Field " is generally used to refer to a comparatively small territory lying in the eastern-central part of Pennsylvania. This territory includes about 3,300 sq. miles of area, located chiefly in five counties in which anthracite-mining is the dominant industry. Although an area of 3,300 sq. miles is embraced in the region, less than one-fifth of this area, or only 484 sq. miles, is underlain by workable coal-seams. Moreover, this prorluctive portion is not a continuous area, but consists of a number of detached basins. These are known as the Northern, containing 176 sq. miles; Eastern-Middle, containing 133 sq. miles; Southern, containing 181 sq. miles; and western-Middle,containing 194 sq. miles. From the standpoint of business and trade, the region is divided into three districts, known as (1) the Wyoming, which includes the Northern field and the small Bernice basin; (2) the Lehigh region, which includes all of the Eastern Middle field and that part of the Southern field east of Tamaqua; and (3) the Schuylkill region, which includes the WesL ern-Middle field and that part of the Southern field west of Tamaqua. The relative commercial importance of these districts at the present time is shown by the coal-shipments as given in the following table :

Jan 1, 1904

By Walter Harvey Weed

CONTENTS. [ ] INTRODUCTION. THIS paper deals with certain ore-deposits whose structural features or mineral contents (or both) result, directly or indirectly, from igneous intrusions and their after-effects. It is largely a discussion of contact metamorphic ore-deposits based upon the physical changes in rocks due to contact action. It involves a classification of ore-deposits only so far as is abso-

Jan 1, 1913

By L. C. Graton

I. INTRODUCTION. The Relations of Scale in Geologic Work. MANY features of human accomplishment rest upon the possibility of representing natural objects on a scale of different magnitude from the actual one. Most drawings, for example, are of very different scale from that of the object depicted, and indeed are useful mainly on this account. More important than the question of mere convenience, however, is that of meeting the physical limitations of vision.1 Thus, a mural

Jan 5, 1913

By George M. Fowler, Joseph P. Lyden

PaGE Scope of this Report.................................................... 206 Production of Tri-State District.......................................... 207 Historical Sketch....................................................... 207 Location and Topography............................................... 211 Geology............................................................... 212 The Tri-State District.............................................. 214 Stratigraphy........................................................... 217 General Geological Section in Tri-State Region....................... 217 Stratigraphic Section of Mineralized part of Boone Formation........... 218 Stratigraphic Section Bird Dog Well.................................. 219 Metamorphism........................................................ 220 Structure............................................................. 225 Regional.......................................................... 225 Due to Metamorphism.............................................. 229 Ore Deposits.......................................................... 231 Types............................................................ 232 Hard-ground Deposits.......................................... 232 Brecciated................................................. 232 Stratified............................................ 232 Sheet Ground............................................. 232 In Dolomite............................................... 233 In Shale.................................................. 233 Soft-ground Deposits.......................................... 233 In the District as a Whole....................................... 233 Ore Minerah and Analysis......................................... 233 Paragenesis....................................................... 234 Conclusions........................................................... 236 Structure.......................................................... 236 Genesis of the Ore.................................................. 237 Future of the District............................................... 239 Acknowledgments..................................................... 239 Discussion............................................................ 239 Scope of This Report The Tri-State district. as outlined in this paper. refers to the entire mineralized area in sout'hwestern Missouri. southeastern Kansas and

Jan 1, 1932

By J. M. Hassler

NOWHERE can there be found a more misleading statement than the old one that "Iron can be manufactured cheaper in the South." During the past decade ironmakers and users of iron have heard varied and sundry stories of the wonderful resources of the Birmingham district, including abundant ore and coal fields, cheap labor, a wonderful climate and similar industrial Utopian statements. Birmingham represents the major portion of the iron business in the South, acid as Birmingham fares so goes the iron business of the South. The intent of this paper is to shed some light on the actual conditions surrounding ironmaking in the South, especially in the Birmingham, or North Alabama, district. By a presentation of facts it is desired to point out that the "cheap iron" of the industrial South is a thing of the past, primarily because of increased labor cost and because labor is radically different in performance to what it was years ago. Also, because most of the raw materials needed in ironmaking that would be classed better than inferior are gone.

Jan 1, 1937

By Richard McCaffery

WHEN we began the study of blast furnace slags we limited our work at first to a study of those slags containing only lime, alumina and silica. On our paper1 on some of the results of this first work, the solubility of sulfur in slags containing no magnesia was reported and the question of sulfur solubility and slag viscosity discussed. There has been, for a long time, a very great difference of opinion among metallurgists as to he effect of magnesia in blast furnace slags, and the literature is full if expressions of the most contrary opinions on the subject. As a result, our next publication' developed the constitution of slags considered as a four-component system, silica-alumina-lime-magnesia, and advanced an explanation of slag structure which accorded with the facts and with scientific theory. The present paper continues our study of the general subject of slags. As blast furnace slags are included in the silica-alumina-lime-magnesia system, which is a particular case of four-component solutions, we have determined that there are 22 components Table 1), which may enter into the silica-alumina-lime-magnesia system and that 10 or 12 of these components may be present in blast furnace slags which are within the ordinary ranges of composition. To cave a very definite conception of the behavior of these components in a slag, we have developed the theory of the cooling of a four-component solution from the liquid state to the solid and the conclusions that we obtained have been made use of in this paper. On account of the importance of the four oxides and 18 compounds which enter into the silica-alumina-lime-magnesia system, some method of calculating the percentages of the various compounds that are present in the slag when the percentages of the oxides are given, seemed very desirable and we develop L method later herein for doing this, and finally we give illustrations of the composition of a wide series of blast furnace slags and show some applications of these composition data.

Jan 1, 1927

By Shun-ichi Satoh

The electric arc welding of cast iron has been studied by Braune Lamberton, Schimpke, Kenyon, Gale Manufacturing Co., Wedemeyer Candy, Neese, Miller, Carter, American Welding Society, Namack Lebrun, Achenbach, Jansson, Xochendorffer and others.' The write of this paper has been able to obtain a series of cast irons, from gray tc white, without using cast-iron electrodes but by coating on wrought-iron bars mixtures of carborundum (Sic) and graphite (C). In this work, he found the curious phenomenon of barium carbonate.

Jan 1, 1929

By W. C. Clark, J. B. Schloen

Two papers have been written, previously concerning operations at the Montreal East plant of Canadian Copper Refiners Limited. The first one,' written in 1932, described silver-refinery operations at the time for producing silver and gold bullion from tankhouse anode slimes; the second,Z published in 1933, consisted of a description of the entire plant. Since publication of these papers the refinery has become the world's largest producer of refined selenium. The first selenium was produced in August 1934. Tellurium production on a commercial scale followed in October 1935. This paper will deal with selenium and tellurium production and also with present operations in the silver refinery. Blister cakes from Hudson Bay Mining and Smelting Co., Flin Flon, Manitoba, and commercial anodes from Noranda Mines Limited, Noranda, Quebec, are refined at Montreal East. Both these bullions have unusually high gold, selenium and tellurium content. The average assay of raw slimes produced from domestic and Noranda anodes is about 40 per cent Cu, 3600 oz. per ton Ag, 800 ox. per ton Au, 22 per cent Se and 3.7 per cent Te. Early Silver-refinery Operations From the start of operations in 1931 until July 1934, the raw slimes were oxidiae-roasted at 700' F. in a Nichols-Herreshoff furnace, acid-leached with tankhouse discarded foul electrolyte (20 per cent HzSOa), filtered and charged directly to the dor6 furnace for refining to dore metal. This is the customary method for treating tankhouse anode slimes but was not suitable at the Montreal East plant because of the high selenium and tellurium content of our slimes. In the acid-leaching process about 50 per cent of the selenium and tellurium in the roasted slimes was dissolved in the electrolyte. These elements were recovered with the copper as a sludge in a small electrolytic

Jan 1, 1944

By Stanley D. Michaelson, Norman Weiss

This was a year of realization. Some years are for planning and development, some for designing and building, others for fulfillment. With greater hopes and plans for the future than ever before, the year 1954, nevertheless, will be remembered principally because of project completion. Among copper mines, for example, there were Silver Bell, Copper Cities, Bisbee, Yerington, and White Pine. In iron, there were the Humboldt, Coleraine, Cerro Bolivar, and Eagle Mountain. In asbestos, Johns-Manville's new mill at Asbestos, Que. In uranium, completion of the ninth mill on the Colorado Plateau-Kerr-McGee's at Shiprock, N. M. In research, 1954 marked the completion of Kennecott's Research Center in Salt Lake City, one of the historic forward strides in the science of minerals beneficiation. The year was fruitful in other directions as well. Investigations of a fundamental nature were on the upswing, and pilot plant projects have also increased in size and number. Progress in new reagents and equipment was greater than normal. It can already be conservatively predicted-from the technological point of view-that 1955 and 1956 will be tremendous years.

Jan 3, 1955

By Richard E. Chism

If internal commotion can be called life, the Mexicans have certainly lived more in the last seventy-five years than any other people. To the oppression of the Spanish viceroys succeeded the sanguinary tumults of the Revolution of Independence, after which the Supreme Congress bequeathed its heritage of uncertain power to the empire of Iturbide, the only one ever established by Americans upon American soil, with an American at its head. That shortlived reign mas followed by years of ceaseless, bloody, and, to the superficial observer, meaningless revolutions—the deeper political and ecclesiastical significance of which it is beyond the scope of this paper to discuss. Then came foreign intervention, the ill-fated Austrian's brief supremacy, and the final triumph of the patriot cause under rugged old Benito Juarez, who crowned the victory of arms by a series of reforms breaking forever the temporal power of the Church and ushering in the calmer era which has lasted from the first accession of Diaz to the present day. During all those troublous times, the revolutionary ocean, that rolled so deeply over all other relics of Spanish dominion, had left almost unaltered the ancient laws of Spain, still lifting themselves above the tide, like landmarks of a flooded world. Many of these laws were obsolete ; some were absurdly inadequate to the demands

Jan 1, 1886

By H. J. R. Way

THE work to be described was undertaken at various periods from 1937 to 1939 on the Busia gold field, in the eastern province of Uganda. It was decided to examine the possibility of reef prospection by the resistivity method, for it was not known how far the usually disintegrated nature of most reefs in the ubiquitous laterite near the surface would obscure indications obtained by resistivity traverses. The work at the commencement was therefore largely experimental, but the results obtained thereby were satisfactory, and a survey was started at the Government closed area at Amonikakine. With the limited time and resources at the writer's disposal, it was not possible to complete the survey to his satisfaction or to follow up exhaustively all the geophysical indications, but some of the results of the experimental work and the survey were of sufficient interest to be worth recording; in particular the relation between the width of reef, electrode separation and shape of the curve, and the interference effect of constant separation curves over zones of float are significant and useful. Three new veins were located, but only one contained sufficient gold to warrant detailed prospection. This was called the Geophysical reef, and was uncovered over a strike distance of 1140 ft., and there are indications that it extends over a distance of 1990 ft. These results and the recommendations consequent therefrom were embodied in a special report to the Uganda Geological Survey. HISTORY OF THE FIELD The Busia field is in the southeastern corner of Uganda near the Kenya-Uganda border, and is about 17 miles north of the northeastern corner of Lake Victoria. Gold was first discovered in the area in the stream beds by Davies1,2 in 1932. Subsequently numerous small alluvial claims were worked by prospectors and the area was prospected for reef by a company for periods varying from three to nine months, but was finally abandoned, as the results were considered unfavorable. Further prospecting by the Geological Survey in 1935-1936 under Davies3 and later under the writer4 uncovered three reefs with sufficient gold values to be of economic interest. These were finally taken over by a company known as Borderland Syndicate, which still owns the area, and from September 1937 to the end of 1941 about 13,000 oz. of gold was extracted from reefs of the area proved by the Geological Survey. Opencast mining operations are still proceeding (February 1943). The Amonikakine area lies to the immediate north of that of Borderland Syndicate. A certain amount of prospecting had been done when the writer started work there. As a result of his report, this area was taken over by another syndicate, but little further work was accomplished before it ceased operating because of difficulties of wartime working.

Jan 1, 1944