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By Joseph Hartshorne

EVER since the introduction of the Siemens regenerative furnace, it has been recognized that a certain amount of gas is lost each time the furnace-action is reversed. This loss comes, first, from the gas which passes through the free connection between the stack and the gas-main, which exists during the time the reversing-valve is turning over; and, secondly, from the gas which is in the chamber and flues, from the hearth to the reversing-valve, and which flows back into the stack when the valve is reversed. The amount lost each time is, of course, small; but, since a furnace is reversed from four to six times every hour for, say, 300 days in the year, the aggregate is large enough to be well worth attention. The estimate has been published' that, in Germany alone, the loss from the first of the above causes amounts to 500,000 marks per year. The loss from the second cause is, of course, much greater. A process for saving this entire loss, in use at Teplitz, Bohemia, for about three years, would seem to be of value even in this country, where coal is cheaper and where the small economies are not watched as closely as they are in Europe. This process, invented by Mr. Adelbert Kurzwernhart, late Technical Director of the Teplitzer Walzwerk, has been worked out with thoroughness. The loss from each cause can be calculated very closely for any particular furnace, and the results to be expected from the process ascertained. It can easily be decided, therefore, whether it is worthwhile to adopt it under any given conditions. The amount of chamber-gas lost depends upon,-(1), the cubic contents of the chamber, ports and flues upon one side of the furnace, up to the reversing-valve (deducting, of course,

Mar 1, 1906

By G. R. Lehman

The Inspiration Consolidated Copper Co. had an orebody at Miami, Ariz., of close to 100,000,000 tons of low-grade copper ore, and the method of mining this ore most profitably was of great importance. The selection of a method was practically limited to a "top-slicing," a "shrinkage-stope" or a "caving" method. The "top-slicing" method would give a high extraction of the developed ore, at a high mining cost, and the "shrinkage-stope" or "caving" methods a lower extraction of the developed ore, at a lower mining cost. Ore-Drawing Tests To decide on the method to be used it was necessary to know about what extraction of the ore could be obtained by the "shrinkage-stope" or " caving " methods. As no definite information regarding the,question was available at the time, C. E. Mills, the general manager, thought that some information could be obtained by experimenting in drawing ore, covered with capping, from an experimental box. Some work had already been done along these lines by W. C. Browning for the Inspiration Copper Co. and by myself for the Live Oak Development Co. The idea was to represent as nearly as possible, in the experimental box, the conditions within an area of caved stopes of caved ore all ready for drawing. That is, the area was supposed to represent a semibroken mass with the capping above it in the same condition and ready to follow the ore downward as it was drawn out of the chutes under the ore. To represent the above condition, in the experimental box, crushed ore from the mine was placed in it to a given height, and red barren capping from the mine was placed on top of the ore. The Experimental Box The experimental box shown in Fig. 1 was made of wood and glass. The glass was used for the sides so that the drawing action of the outside row of chutes could be seen and noted, the latter being cut in the center by the glass sides. The length of the box was 30 in., width 20 in. and the

Jan 1, 1917

By C. M. Haight

THE mine blacksmith and drill-steel sharpening shop at the Franklin mine of the New Jersey Zinc Co. is on the surface, adjoining the main shaft. It is a brick building, 51 by 30 ft. inside dimensions, with a corrugated iron roof and concrete floor. About two-thirds of the steels used are brought up through the main shaft; the remainder through two auxiliary shafts. The latter are carried to the shop by team or truck. At each shaft sufficiently large stocks of sharp drills of various types are kept to replace all the dull steels that may be sent up; while at the shop enough sharp drills are kept to replace the dull steels in the stocks kept at the auxiliary shafts. Though this entails keeping a larger number of drill steels in service than might be required by other methods, there is less hurry in the sharpening shop and the steels have a longer period of rest. If a rest from use enables steel to recover from fatigue strains, this method secures that rest. The forms shown in Fig. 1 are supplied to each shift boss in books of 100. These are used to requisition sharp drills from the shaft stocks and enable the men at the tops of the shafts to sort out the required sizes and to have them ready to be sent to the various shaft stations. At one of the auxiliary shafts, the dull drills are placed on a platform from which they are dumped into the body of the wagon that takes them to the shop.

Jan 2, 1926

By Harold A. Krueger

FACILITIES and mining operations of the National Lead Co., St. Louis Smelting and Refining Division, near Fredericktown, Mo., are situated in a famous mining area. Copper, lead, nickel, and cobalt have been mined here for more than 100 years, work having been started on a high sulphide copper outcrop in 1847. Lamotte sandstone is characterized by differential compaction on a rigorously eroded pre-Cambrian surface. The Bonneterre formation was therefore a good host for minerals not generally found in mineable quantities in these midwestern areas. Unusually complex minerals, however, make beneficiation difficult, and because of irregular ore thicknesses and elevations many engineers and operators have not attempted to mine the property. Others have tried who failed. This paper deals with economic, efficient, and competitive methods of mining these highly irregular orebodies, as compared to the open-stope, room-and-pillar methods normally used for horizontal-bedded lead deposits. For the purpose of this study it should be understood that the ore is found in two distinctly different types of occurrences, one to be designated as basin ore and the other as contact ore. Mining of basin ore is complicated by many faults, fractures, cross faults, and breaks. Contact ore is complex because it is found on flanks or slopes of pre-Cambrian knobs or highs. The dip of the mining floor for the latter type varies between 18" and 45". Occurrences of both types of ore are complicated by water courses or solution channels which carry unconsolidated shale, lime, sand, and dolomite. This material is also found between the bedding planes of the members of the Bonneterre formation. The water found where there are fractures, faults, and channels makes it very fluid and tacky, see Fig. 1, particularly after it has been blasted and handled by loading and hauling machines. Much of the ore can be wadded and thrown without dispersing. During early operations by the Buckeye Copper Co. in 1861 and the North American Lead Co. from 1900 to 1910, conventional narrow-gage railroad and side dump mine cars were used with hand shoveling. The complications of mining the contact ore, the only type attempted at this time, can be appreciated when it is realized that operators were obliged to use mules for haulage. Haulageways constructed on these slopes were of necessity similar to wagon trails or goat trails up the side of a mountain. In other words, it was merely a matter of going from side to side of the strike length of the slope, gaining a little in elevation on each shuttle trip. Production totaled only one to two tons per manshift. A few years later, about 1913, the property was purchased by combined Canadian interests known as the Missouri Cobalt Co., and the use of trolley locomotives was initiated. Between 1900 and 1928 a land agent using churn and diamond drilling methods prospected scattered sections of the area. In 1928 the first property was purchased by the present company, then operating as the St. Louis Smelting and Refining Co. Check drilling and prospecting was carried out by the company at various times between 1928 and 1939 to correlate the erratic mineralization. Much information about both types of orebodies was accumulated, but it was still questionable as to whether money should be invested to work these occurrences. In anticipation of high lead and copper prices, about the time World War II started, it was decided to develop and bring into production some of this ore. In 1942 No. 1 shaft was put down on the largest basin-type orebody and in 1943 No. 2 shaft was put down on contact-type ore. Operations were expanded when No. 3 shaft was completed in 1943, and progressed further in 1948, when National Lead Co. dewatered and opened No. 5 and 6 mines, old workings of the North American Lead Co. and the Missouri Cobalt Co. Because of the differential compaction of Lamotte sandstone over the pre-Cambrian porphyry, in some instances mineable thicknesses of basin-type ore occurred 20 to 30 ft above the sand. This is the exception rather than the rule, since most of the mineralization starts at the sand and is variable in thickness. The ore was attacked, therefore, by development drifts and crosscuts at the lowest possible elevation, where the ore immediately overlying the Lamotte sandstone could be drained and made accessible for mining. It was planned to connect to the drifts and crosscuts with raises to mine ore deposited 20 to 30 ft higher. The higher orebodies were thus mined as slusher levels. Slusher hoists were used to drag the ore into the raises, which were made into hoppers. The ore was then loaded into 32x32-in. ore cans, hauled to the shaft by battery locomotives, and hoisted by the conventional Tri-State method. The rate of efficiency was 5 to 6 tons per manshift underground. The contact-type ore was attacked in a similar way, except that the orebodies were not nearly so wide, so that they were more flexible for slusher loading into cans. This advantage was offset, however, by haulage complexities, since the railroad was constructed on steep slopes. Through experience and ingenuity, many improvements were made in mining both types of ores. The two levels, so-called, in the basin-type ore-bodies were connected as previously planned, more efficient locomotives replaced the older ones, and a

Jan 1, 1954

By D. J. Jr. McAdam

This paper presents stress-cycle graphs for five samples of monel metal and three high-strength aluminum alloys. These graphs are evidently curves with horizontal asymptote. The position of the horizontal asymptote can be determined with sufficient accuracy by extending the experiments to not more than 50,000,000 cycles. For some of the graphs, there is a slight downward slope between 50,000,000 and 100,000,000 cycles. The slope is so slight, however, that, extrapolation from 50,000,000 to 100,000,000 cycles gives the endurance limit with sufficient accuracy. Monel metal and duralumin are not exceptional among non-ferrous metals in endurance properties. IN Part I of this paper' a comparison was given of the results obtained in investigation of the endurance properties of non-ferrous metals in .three laboratories: the Engineering Experiment Station of the University of Illinois, the U. S. Air Service at McCook Field, Dayton, Ohio, and the U. S. Naval Engineering Experiment Station, Annapolis, Md. Part I was devoted to a discussion of the forms of the stress-cycle graphs obtained at the three laboratories. For comparison, typical graphs obtained at the three laboratories were plotted on the same semi-logarithmic scale. The typical rotating-cantilever graph for ferrous and non-ferrous metals obtained at the Naval Experiment Station was described as a curve descending with gradually decreasing slope to a horizontal line. In the reply to the discussion of Part I, however, this graph was described as a curve with horizontal asymptote. It. was also said that the ordinate of the asymptote (the endurance limit) could be determined by endurance tests of not more than 50,000,000 cycles. This description was intended to apply only within the range of ordinates used in plotting an ordinary endurance graph. It was recognized that if .extended upward beyond the usual field, the curvature of the graph would decrease until -the graph would either approach a straight a line or possibly reverse its curvature.

Jan 2, 1926

By Frank R. Milliken

This paper is a running commentary on metallurgical problems and developments, stressing ilmenite flotation, since the start of operations five years ago, at the mill of National Lead Company, Titanium Division, MacIntyre Development, Tahawus, New York. In early 1941, when world conditions threatened to cut off the supply of ilmenite (obtained largely from India) to this country, the National Lead Company started to develop and bring into production their MacIntyre Development. This operation supplied the bulk of the ilmenite used during the war period for the manufacture of the much needed titanium pigments. MacIntyre Development is at Tahawus, New York, on the headwaters of the Hud- son River in the center of the scenic Adirondack Mountains. A general description of the operation was given in the Adirondack Issue of Mining and Metallurgy for November 1943. Operating tonnages and production have increased since 1943, however. Nearly 10,000 tons of.ore and waste is broken and loaded daily in the open-pit mine. About half of this tonnage is ore, from which is produced nearly 800 tons of ilmenite concentrate and 1600 tons of magnetite concentrate daily. Ore—types From an ore-dressing standpoint, there are five rather distinct ore types and two waste-rock types in the mine. The ore types are shown in Table I. The anorthosite waste is a coarse-grained white rock, largely labradorite feldspar. The gabbro waste is generally finer grained, and contains, in addition to feldspar, 35 to 75 pct iron silicates such as hornblende, in garnet and biotite. A minor mineral mineralogically, but important metallurgically, is apatite. A few calcite

Jan 1, 1949

By MARIUS R. CIMPBELL, Edward W. Parker

DESCRIPTION. ACCORDING to the estimates prepared by the U. S. Geological Survey, the area underlain by workable coal-beds in the United States is 496,776 sq. miles. Of this total area, 480 sq. miles contain the entire anthracite coal-fields of Pennsylvania. The bituminous coal-fields are estimated to be contained in areas aggregating 250,051 sq. miles. The grade of coal between bituminous and lignite, and which is designated by the Geological Survey as " sub-bituminous," is estimated to be contained within areas aggregating 97,636 sq. miles, while the areas containing lignite aggregate 148,609 sq. miles. The coal-fields are divided, for the sake of convenience in classification, into six main provinces, as follows: 1. The Eastern. Province, containing the anthracite coal-fields of Pennsylvania and the bituminous coal-fields of the Appalachian region-namely, those of western Pennsylvania, Ohio, Virginia, West Virginia, Kentucky, Tennessee, Georgia, Alabama, and small outlying areas in North Carolina. 2. The Interior .Province, containing the bituminous coal-producing regions of Michigan, Illinois, Indiana, western Kentucky, Iowa, Kansas, Missouri, Oklahoma, Arkansas, and Texas. 3. The Gulf Province, containing the lignite-areas of Alabama, Mississippi, Louisiana, Arkansas, and Texas. 4. The Northern or Great Plains Province, containing the lignite and sub-bituminous areas of North and South Dakota, eastern Montana, and northeastern Wyoming. 5. The Rocky Mountain Province, containing the bituminous and sub-bituminous areas of western Montana and western Wyoming, Colorado, Utah, and New Mexico. 6. The Pacific Coast Province, containing-the areas of Washington, Oregon, and California.

Apr 1, 1909

By Paul A. Beck

THE occurrence of the (100) [lOO] or "cube" texture upon annealing of cold-rolled copper has been much investigated.' The conditions favorable for its formation were found to be a high final annealing temperaturez or long annealing time," a high reduction of area in cold rolling prior to the final anneal,' and a small penultimate grain size." The effects of penultimate grain size and of rolling reduction were found by Cook and Richards4 to be interrelated in such a way that any combination of them giving lower than a certain value of the final average thickness of the grains in the rolled material leads to a fairly complete cube texture with a given final annealing time and temperature. Also, according to the same authors, at a higher final annealing temperature a larger average rolled grain thickness, i.e., a lower final rolling reduction, is sufficient than at a lower temperature. These somewhat involved conditions can be understood readily on the basis of recent results obtained at this laboratory. Hsun Hu was able to show recently by means of quantitative pole figure determinations that the rolling texture of tough pitch copper, which is almost identical with that of 2s aluminum: may be described roughly as a scatter around four symmetrical "ideal" orientations not very far from (123) [112]. In the case of aluminum, annealing leads to retain-ment of the rolling texture with some decrease of the scatter around the four "ideal" orientations, and to the appearance of a new texture component, namely the cube texture." A microscopic technique, revealing grain orientations by means of oxide film and polarized light, showed that the retainment of the rolling texture is achieved through two different mechanisms operating simultaneously, namely "re-crystallization in situ," and the formation of strain-free grains in orientations different from their local surroundings, but identical with that of another component of the rolling texture. Thus, a local area in the rolled material, having approximately the orientation of one of the four "ideal" components of the texture, partly retains its orientation during annealing, while recovering from its cold-worked condition, and it is partially absorbed at the same time by invading strain-free grains of an orientation approximately corresponding to that of another "ideal" texture component. The reorientation here, as well as in the formation of the strain-free grains of "cube" orientation, may be described as a [Ill] rotation of about 40°, see Fig. 1 of ref. 6. The preferential growth of grains in such orientations is a result of the high mobility of grain boundaries corresponding to this relative orientation.' " It appears very likely that in copper the mechanism of the structural changes during annealing is similar to that observed in aluminum (except for the much greater frequency of formation of annealing twins in copper). In both metals the new grains of cube orientation have a great advantage over the new grains with orientations close to one of the four components of the rolling texture. This advantage stems from their symmetrical orientation with respect to all four retained rolling texture components of the matrix; they are oriented favorably for growth at the expense of all of these four orientations. As a result, the growth of the "cube grains" is favored over the growth of the others, as soon as the new grains have grown large enough to be in contact with portions of the matrix containing elements of more than one, and preferably of all four component textures. It is clear that this critical size is smaller and, therefore, attained earlier in the annealing process if the structural units, such as grains and kink bands, representing the four matrix orientations are smaller, i. e., if the average thickness of the rolled grains is smaller. Hence, for a given annealing time and temperature, a smaller penultimate grain size and a higher rolling reduction both tend to increase that fraction of the annealing period during which the above condition is satisfied. Consequently, the percentage volume of material assuming the cube orientation increases. The same is true also for increasing time and temperature of annealing when the penultimate grain size and the final rolling reduction are constant, since the average size attained by the new grains during annealing increases with the annealing time and temperature. For the same reason, at higher annealing temperatures a given volume percentage of cube texture can be obtained with larger rolled grain thickness (larger penultimate grain size, or smaller rolling reduction) than at lower annealing temperatures. The well-known conspicuous sharpness of the cube texture may be interpreted as a result of the fact that selective growth of only those grains is favored that have an orientation closely symmetrical with respect to all four components of the deformation texture and exhibit, therefore, a high boundary mobility in contact with each. The effect of alloying elements in suppressing the cube texture, as described by Dahl and Pawlek,' appears to be associated with a change in the rolling texture. For face-centered cubic metals, such as copper, which do exhibit the cube texture upon annealing, the rolling texture is always of the type described above, i. e., scattered around four "ideal orientations" of approximately (123) [112]. The addition of certain alloying elements, such as about 5 pct Zn or 0.05 pct P in copper, has the as yet unexplained effect of changing the rolling texture into the (110) 11121 type. This texture consists of two fairly sharply developed, twin related components. In such cases, as in 70-30 brass and in silver, the annealing texture again is related to the rolling texture by a [lll] rotation of about 30°, however, because of the different rolling texture to start from, it has no cube texture component. At higher temperatures, both in brassm and in silver," grain growth leads to a further change in texture: A [lll] rotation of the same amount, but in reversed direction, back to the original rolling texture.

Jan 1, 1952

By M. J. Langley

The American Zinc Company’s mining operations in East Tennessee are located in Knox and Jefferson Counties. Mineralization occurs, intermittently, through a strike length of more than 30 miles, from near the eastern edge of Knoxville northeastward to a few miles beyond Jefferson City. The presence of zinc in these Counties has been known for well over 100 years. In 1910 it was brought to the attention of American Zinc Company that zinc sulphide deposits in the Mascot area might be attractive. Following an examination and some surface prospect drilling, the American Zinc Company of Tennessee was organized and acquired the Mascot properties in 1911. Operations began in 1913 on the basis of 1,000 tons per day mill capacity. With the successful operation of the Mascot mines, the Company undertook explorations in the area from Jefferson City southwest through Friends Station to Mascot. The efforts resulted in development of substantial tonnages of zinc ore and enabled the Company to expand the Mascot and New Market milling operations to their present capacity of 11,100 tons per day. Folded and faulted Paleozoic sedimentary rocks under- lie the mining district. The principal zinc mineralization occurs in a group of strata known as the Knox

Jan 1, 1970

By D. J. Carney, C. W. Boquist, E. C. Rudolphy

Effect of variations in sinter feed composition on sinter strength, bulk density, re-ducibility, chemical composition, and microstructure were determined by sintering experimental samples on a production sintering machine. Increasing amounts of roll scale, ore fines, return fines, and blast furnace slag were most beneficial to feed permeability, sinter bulk density, and strength. Burnt lime additions improved feed permeability but were not beneficial to sinter strength or bulk density. Sinter reducibility was adversely affected by all additives. DEVELOPMENT of methods for evaluating sinter quality, which would in some way predict the behavior of the sinter during charging and smelting in the blast furnace, has been given considerable attention in recent years. In a previous investigation at South Works of the United States Steel Corp., standard sinter sampling and testing procedures were developed.1,2 By modifying the sinter sampling device, a method of sintering experimental mix sinter samples upon a production Dwight-Lloyd sintering machine was also developed. This technique afforded a rapid and controlled method of investigating the effects of the various raw materials and additives on sinter quality and was used in this present investigation. Since the beginning of the present study in 1953, the results of numerous sinter investigations have been published, most of which were concerned with production tests of iron ore sinter, both here and abroad. Three groups of investigators reported results of experimental sinter studies that were related to this investigation. Voice et al.3 studied the effects of controlled variables on sinter quality by producing and testing experimental Northants iron ore sinter using an experimental sintering unit. Mor-rissey and Powers' determined the relationship between iron ore sinter quality and the moisture and coke content using a small laboratory sintering system. Burlingame et al.5 studied the effects of "additives" upon iron ore sinter using a laboratory sintering apparatus and laboratory grade raw materials. At South Works, it was considered desirable to study the effects of sinter mix composition and additives upon the quality of a flue dust-base sinter produced on a production sintering unit. Extrapolation of controlled laboratory test data to sintering plant operation lacking such precise control is not altogether satisfactory. Therefore, the present study was conducted in a manner which approximated production conditions as closely as possible. The raw materials used were those commonly encoun- tered in the production of flue dust and flue dust ore-type sinters and these were varied within extremes encountered in this type of sinter production. Experimental Procedure The experimental sinters were produced from 100 lb mixtures of sinter feed. The principal raw materials and additives used, their particle size, and approximate chemical composition are listed in Table I. The mixing of the raw materials was accomplished by means of a miniature single shaft pug mill shown in Fig, 1. The use of the pug mill as a mixer was decidea upon after encountering difficulty in reproducing the mixing and chopping effect of the sinter plant pug mill with other types of available small mixers. The miniature pug mill was constructed, consisting of 31/2x2x1/4 in, blades spaced 3 in. apart along a 3 ft shaft. Preliminary tests were run with this small mixer to establish the proper rotation speed and the required number of passes through the pug mill to thoroughly mix and distribute all the raw materials in a manner approximating the production Pug mill- Although the effects of varying the mosture content were determined in one particular series of tests, the amount of moisture added was changed as the composition of the experimental mix was varied. The aim in making water additions was to achieve a permeability as high as possible for each particular

Jan 1, 1956

By F. Kurata, P. C. Davis, T. L. Gore

An experimental method and apparatus for the study of the low-temperature phase and volumetric behavior of volatile mixtures are described. The phase diagrams, including the critical points, and the volumetric behavior of a natural gas and a mixture of the natural gas with methane at temperatures from -40°F to -200°F and pressures to 1.200 11si are givrn. INTRODUCTION Knowledge of the phase and volumetric behavior of mixtures of the light hydrocarbons at low temperatures is becoming increasingly important as interest in low-temperature separation processes increases. Distillation at low-lemperatures has been used for some time to recover ethane and ethylene from natural gas and refinery gas for petrochemical uses. Removal of excess nitrogen from natural gas by distillation has been proposed as a means of increasing the capacity of gas transmission lines and of improving the marketability of the gas.1,2 Evaluation of the latter process has been hampered, however, by the scarcity of data from which the phase behavior of natural gases at low temperatures might be predicted. While existing correlations of vaporization equilibrium constants may be used to predict the behavior of such mixtures at lower pressures, high-pressure computations often require knowledge of the location of the critical point of the system involved. Although correlations have been developed for the prediction of the critical temperature and pressure of certain types of hydrocar-bon systems, they do not apply to very volatile systems such as nitrogen-bear-ing natural gases. This paper describes the initial stages of an investigation of the low-temperature behavior of a numher of natural gases and other gases of commercial interest. The experimental method and apparatus are described. and the phase and volumetric behavior of a natural gas and a mixture of the natural gas with methane are presented. PREVIOUS WORK The published low-temperature vapor-liquid equilibrium data for hydrocarbons and mixtures of hydrocarbons with nitrogen and helium are listed in Table I. Most of these data are for binary systems, and the data of Stutz-man and Brown" at 100 psi are the only data on a natural gas. The data of Bloomer and Parent3 on the methafie-nitrogen system, which have been phblished since this study was completed, are a valuable addition to the knowledge in this field. Prior to the publication of these data the only published critical point data on systems having critical temperatures below the ice point were those of Ruhemann.1 on the methane-

Jan 1, 1952

By William Fink

ZINC is one of the effective elements introduced to enhance the strength of aluminum. This strengthening is principally attributable to the high solid solubility of zinc in aluminum and the pronounced variation of solubility with temperature. Consequently an accurate determination of the solid solubility curve is desirable. The solid solubility relations have been studied by numerous investigators. Shepherd' first established the existence of a solid solution region at the aluminum end of the diagram (y phase) by specific volume and microscopic determinations. Bauer and Vogel2 published a constitutional diagram which showed the limits of solid solubility as determined by thermal and microscopic methods. Hanson and Gayler3 presented the aluminum-zinc diagram which is now most generally accepted (Fig. 1). Chill-cast samples were given thermal treatments designed to obtain equilibrium conditions, quenched, and microscopically examined.. The solubility was placed between 15 to 20 per cent at 600 C., 20 to 22 per cent at 140° C. and 36 to 38 per cent at 270° C. Sander and Meissner4 decidedly modified the limits of they phase field of Hanson and Gayler's diagram by using similar methods on chill-cast specimens annealed for a shorter period of time. Tanabe,5 utilizing dynamic hardness, electrical conductivity and dilatometric measurements of specimens at temperature, obtained values comparable to Hanson and Gayler's at room temperature, but appreciably lower at higher temperatures. Nishimura6 concluded from age-hardening results of aluminum-zinc alloy chill castings, which had been quenched from 400° to 500° C., that the solubility of zinc in aluminum at room temperature is less than 5

Jan 1, 1932

By P. R. Sperry, P. A. Beck, Hsun Hu

As described by means of quantitative pole figures, the inside texture of highly rolled aluminum and copper strips may be approximately described by four equivalent ideal orientations near (123) [121]. If rolled in reversed passes, the surface texture of copper is also near (123) [121], that of aluminum is (100) [011]. The inside texture of highly rolled brass is (110) [112]. The surface texture is the same, if rolled in reversed passes. The surface texture of all three metals is related to the inside texture, but asymmetrical, if rolled without reversal between passes. MANY previous investigations dealing with the subject of the present work were reviewed by Wassermann.1 Barrett,2 Brick,3 and Richards.' The recent introduction of quantitative methods for pole figure determination by Decker, Asp, and Harker,5 Schulz5 and others made it possible to reinvestigate some of the finer points which the earlier more qualitative photographic methods left undecided. The rolling textures of silver and of 70-30 cartridge brass have been quite consistently characterized by the ideal orientation of (110) parallel to the plane of rolling and [112] parallel to the rolling direction. On the other hand, it has been recognized by several investigators that certain other face-centered cubic metals, such as copper and aluminum, developed rolling textures rather different from that of brass. These textures have been variously described by the following ideal orientations, singly or in combinations with each other: (110 [112]: (112) [111]; (135) [335]; (135) [211], etc. The discrepancies usually have been attributed to the lack of sharpness in the textures and to the attendant difficulty of associating "ideal orientations" with pole figures showing great scatter of orientations. It seemed desirable to investigate by the new quantitative methods to what extent the apparent lack of sharpness may have been brought about by the qualitative methods used previously, rather than by the textures themselves, and to decide, if possible. between the various ideal orientations which have been proposed. Another problem, not satisfactorily settled by earlier investigations. concerns surface textures in rolled metals. For instance, in rolled aluminum the surface texture in some cases appeared to be similar to the texture inside the sheet, whereas in other cases it was reported to be entirely different.' The conditions under which such differences may have arisen, and the possibility of the occurrence of different surface textures in other face-centered cubic metals do not appear to have been examined in detail. The present work was undertaken to investigate the above questions. Some of the results obtained have been described- riefly. Experimental Procedure Specimen Preparation: In the present investigation 2s aluminum, electrolytic tough-pitch copper, and commercial 70-30 brass were used. These materials were available in the form of cold-drawn rods. 1 in. diam for tough-pitch copper and commercial 70-30 brass and 11/2 in. diam for 2s aluminum. The cold-drawn bars were alternately annealed and rolled 30 pct lengthwise in several cycles until a penultimate thickness of 0.500 in. was reached. The intermediate and the penultimate anneals were carried out for 30 min at 380°C with 2s aluminum, and for 30 min at 550°C with 70-30 brass. For tough-pitch copper, the intermediate anneals were 30 min

Jan 1, 1953

By C. A. Gibbons

AFTER nine years of extremely de- pressed business, marked mostly A with red ink on the balance sheets of most coal companies and with an increasing internal competitive struggle for diminishing markets, somewhat of a change appeared during 1939. Shipments increased and prices generally firmed, giving the coal industry increasing optimism and encouragement for the future. Specifically, it now appears that bituminous coal production for 1939 will approximate 378,000,000 tons, and anthracite production will approximate 47,500,000 tons, bituminous production being around 14 per cent ahead of 1938 and anthracite production 12 per cent better. The curve on p. 31, showing both bituminous and anthracite production, furnished by the bituminous coal division of the Department of the Interior, shows graphically most of the 1939 monthly production and clearly illustrates the increased production.

Jan 1, 1940

By P. H. Mell

THE little village, from which this formation receives its name, is situated on a bluff of the Alabama River, 175 feet above water level. This bluff is a portion of high table land that begins in the western portion of Choctaw and extends through Clarke and Monroe counties. We find points on this ridge more than 100 feet higher than Tuscaloosa, and nearly as high as the Tennessee River at Tuscumbia. Through this the Alabama River cuts its way, exposing a beautiful cross-section of the strata, of which the accompanying sketch may give some idea. The fossils are found about 75 feet below the surface and 100 feet above the level of the river. There are seven distinct strata. 1. The lowest, extending from the water's edge up the bluff 80 feet, is a soft calcareous rock containing about 15 per cent. of carbonate of lime, with occasional specks of mica. In this a few Ostrea, Turritellce, and Flustrce were found, but so friable as to fall to pieces when handled. 2. Next comes a stratum varying from 2 to 8 feet, consisting of

Jan 1, 1880

By Edward Sampson, Allan B. Griggs

Surveying of many holes drilled by the U. S. Bureau of Mines in the Metaline district has shown surprising deviations. The holes start in the Ledbetter slate (Ordovician) and pass into the underlying gently dipping Metaline limestone (Cambrian) at varying depths, locally in excess of 1000 it. All holes start vertical, but one had deflected as much as 35° at a depth of only 300 it. One hole was found to be deflected 70' at a depth of 1000 ft. These deviations were not indicated to the drillers by any action of the rods or machines. Analysis of the survey data in the light of the observed geology indicates that the holes deviate most in the Ledbetter slate and scarcely at all in the Metaline limestone. The upper part of the "limestone'" in most holes is a massive rock strongly altered by hydrothermal action and essentially homogeneous. The slate is only obscurely bedded but has a cleavage, varying from slight to strong, which is unrelated to bedding. Drill holes have deflected to become nearly perpendicular to the cleavage. Several plans and cross sections are submitted showing the behavior of various holes. Introduction The Metaline district of northeastern Washington has received much attention recently and has promise of becoming even more important as a source of zinc than at present. Exploration has been conducted largely by deep diamond drilling, and in the course of this work it was found that holes became seriously deflected. This paper deals with the nature and causes of these deflections. The district lies along the Pend Oreille River in the northeastern corner of Washington, about loo miles north of Spokane, 9 miles from British Columbia, and 15 miles from Idaho. Three mines are now in operation and for a number of years have furnished a considerable production of zinc and lead. The ore contains zinc and lead in a ratio of about 31/2 to I, and occurs in the upper part of the Metaline limestone of Cambrian age, the upper member of which, where unaltered, is a rather pure limestone. This is overlain by Ledbetter slate of Ordovician age. Ore has formed by replacement of limestone, commonly 100 to 200 ft. below the slate, in areas of gentle dip, resulting in extensive tabular ore bodies. In and near ore, limestone has been intensely altered to granular dolomite and fine-grained quartz, which, where it predominates, forms "jasperoid." As part of their war program, the Geological survey and Bureau of Mines of the U. S. Department of Interior have been cooperating in an investigation of the district. The exploration by the Bureau of Mines in 1943 and 1944 was conducted largely by deep diamond drilling in which as much as 1000 ft. or more of Ledbetter slate was penetrated before the ore-bearing Metalin-2 limestone was reached. During the course of this drilling it was found that holes were seriously deflected while traversing the Ledbetter slate.

Jan 1, 1949

By Edward Sampson, Allan B. Griggs

Surveying of many holes drilled by the U. S. Bureau of Mines in the Metaline district has shown surprising deviations. The holes start in the Ledbetter slate (Ordovician) and pass into the underlying gently dipping Metaline limestone (Cambrian) at varying depths, locally in excess of 1000 it. All holes start vertical, but one had deflected as much as 35° at a depth of only 300 it. One hole was found to be deflected 70' at a depth of 1000 ft. These deviations were not indicated to the drillers by any action of the rods or machines. Analysis of the survey data in the light of the observed geology indicates that the holes deviate most in the Ledbetter slate and scarcely at all in the Metaline limestone. The upper part of the "limestone'" in most holes is a massive rock strongly altered by hydrothermal action and essentially homogeneous. The slate is only obscurely bedded but has a cleavage, varying from slight to strong, which is unrelated to bedding. Drill holes have deflected to become nearly perpendicular to the cleavage. Several plans and cross sections are submitted showing the behavior of various holes. Introduction The Metaline district of northeastern Washington has received much attention recently and has promise of becoming even more important as a source of zinc than at present. Exploration has been conducted largely by deep diamond drilling, and in the course of this work it was found that holes became seriously deflected. This paper deals with the nature and causes of these deflections. The district lies along the Pend Oreille River in the northeastern corner of Washington, about loo miles north of Spokane, 9 miles from British Columbia, and 15 miles from Idaho. Three mines are now in operation and for a number of years have furnished a considerable production of zinc and lead. The ore contains zinc and lead in a ratio of about 31/2 to I, and occurs in the upper part of the Metaline limestone of Cambrian age, the upper member of which, where unaltered, is a rather pure limestone. This is overlain by Ledbetter slate of Ordovician age. Ore has formed by replacement of limestone, commonly 100 to 200 ft. below the slate, in areas of gentle dip, resulting in extensive tabular ore bodies. In and near ore, limestone has been intensely altered to granular dolomite and fine-grained quartz, which, where it predominates, forms "jasperoid." As part of their war program, the Geological survey and Bureau of Mines of the U. S. Department of Interior have been cooperating in an investigation of the district. The exploration by the Bureau of Mines in 1943 and 1944 was conducted largely by deep diamond drilling in which as much as 1000 ft. or more of Ledbetter slate was penetrated before the ore-bearing Metalin-2 limestone was reached. During the course of this drilling it was found that holes were seriously deflected while traversing the Ledbetter slate.

Jan 1, 1949

By J. E. Korski

Quebec Cartier Mining Co. operates a low-grade iron ore deposit at Lac Jeannine, Que., which is located at the extreme southwestern end of the Quebec-Labrador Trough (Fig. 1). The facilities there include one of the world's largest concentrators, a hydroelectric plant of 60,000 hp, and the modern town of Gagnon. A 191-mile railway connects the mine to the seaport situated at Port Cartier on the St. Lawrence River. The harbor in Port Cartier can accommodate both lake and large ocean- going vessels and is also the site of a major grain terminal. The concentrator in Lac Jeannine is designed to produce some 8 million tpy (tons per year) of specular hematite concentrate, containing 66% Fe, from approximately 20 million tons of crude ore. An annual stripping program of 5 to 8 million cu yd of waste rock uncovers the required ore. Approximately 100,000 tons of ore and waste are removed daily on a year-round, 24-hr-per-day basis. The open pit covers an area with maximum dimensions of 8,000 x 2,600 ft (Fig. 2). Present mining plans call for an ultimate depth of approximately 1,000 ft below original ground level. The rocks in the pit area are typical of this portion of the Grenville geological province. They consist largely of marble, quartz rock, pegmatite, iron formation, and stratigraphically older gneisses. The iron-ore formation consists of medium to coarse-grained specular hematite in a quartz host rock. The formation occurs locally in a plunging, anticlinal form. The topography in the vicinity of the mine is rolling, with maximum variations in elevation of about 400 ft. The hills are thickly wooded with birch, black spruce, and some tamarack. Lakes and muskeg areas are plentiful. Precipitation and temperature records have been kept since 1959. The annual rainfall has ranged between a low of 23 in. and a high of 42 in.

Jan 1, 1969

By K. G. Davis, P. Fryzuk

WEINBERG,' in an investigation of solute distributions along unidirectionally solidified rods of dilute silver in tin alloys, concluded that, for rods of 2 mm diameter or larger, a very high degree of convective mixing takes place in the melt ahead of the advancing interface. Suggested causes for this mixing were (1) thermal convection, (2) convective currents set up by changes in fluid density associated with concentration gradients, and (3) currents set up by changes in volume during freezing. Evidence was presented that causes (2) and (3) were not primarily responsible for solute mixing. Further, convective mixing took place in horizontal rods with temperature gradients as low as 6°C per cm, putting doubt on the importance of thermal convection. In the present work, convective mixing is examined in melts with known initial solute distributions. The absence of a moving solid-liquid interface eliminates convection caused by volume changes on solidification. In the first experiment, three silica tubes 2 mm in diameter and approximately 20 cm long were filled with an alloy of 100 ppm Ag in tin (99.999 pct purity), placed adjacent to one another in a horizontal furnace, and solidified from one end at 1 cm per hr. A110, a Y emitter, was used as tracer. A few centimeters at the start of the rod were left un-melted, to determine the initial concentration Go. After solidification was complete, one sample was removed. The hot furnace was then brought back to

Jan 1, 1965

By I. L. Greninger

THE property of the Andes Copper Mining Co. is in the central part of the Republic of Chile, Province of Atacama, 147 km. (91.5 miles) eastward by rail from the port of Chañaral. At this point the Andean system is made up of two principal ranges. The mine is on the westerly slope of the outer, or western, range, at a mean elevation of 3250 m. (10,500 ft.). A meter-gage railroad extends from the company's port at Barquito, near Chañaral, to the reduction plant at Potrerillos. This road has a total length of 151 km. (94.0 miles), of which 93 km. (57.79 miles) are owned by the Andes Copper Mining Co. The remainder of the road is owned by the state. The company operates its trains over the portion of the road owned by the state, under an agreement with the Chilean Government. The mine is connected with the reduction plant by a meter-gage railroad, 10 km. (6.214 miles) long, which extends from the coarse ore bins at the metallurgical plant to the underground storage bins at the mine. Tunnels make up 60 per cent. of the total length of this railroad. As is characteristic of the Andean region in Chile, the topography of the locality is extremely rough, and a number of points near the mine have elevations of from 15,000 to 16,000 feet.

Jan 1, 1928