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By Benjamin Smith Lyman

THE importance of topography to geology is so commonly underrated as to deserve to be pointed out again and again. The relation of topography to the different branches of geology may be seen best by a glance at them all. Geology is well understood to consist of the observation of facts about rocks as materials of the earth (geognosy ), and the explanation of those facts (geogeny). The facts to observe are: I. GEOMETRICAL, as (1) structure, including the dip and strike at different points, the size, shape, and position of basins and saddles; (2) vertical section, that is, the thickness of rock groups and of their parts ; (3) horizontal or geographical position. II. PHYSICAL, such as texture, whether sedimentary or crystalline ; and, if crystalline, whether granitic, porphyritic, amygdaloidal, globular, or concretionary; whether compact or granular; coarse or fine; pervious or impervious; hard or soft; firm or tender; with cleavage or without; massive or thin; the microscopic structure; also whether magnetic or not; soluble or insoluble; fusible or infusible; and the constituent minerals. III. CHEMICAL, that is, the composition of the rocks and of their minerals and their affinities. IV. PALÆONTOLOGICAL, as what kind of fossils are in the rocks,

Jan 1, 1873

ONE of the perplexing problems that face the translator of an old technical treatise is the question of terms for units of weight and measure. We have used an English word only when it is linguistically equivalent to the Italian one and is a unit of approximately the same size. Libbra and oncia thus become pound and ounce, for the actual weights were within 10 per cent of the modem Troy weights. On, the other hand, the length measures braccio, palmo, and dito, which could be rendered literally as arm, palm, and finger or digit, respectively, have no good English metrological equivalents and it has seemed best to retain the Italian words. The exact transfer of Biringuccio's weights and measures into modern terms is impossible because of the uncertainty as to his standards. Even as late as 1803, when the metric system was first introduced into Italy, practically every city had its own standards. There were, for example, at least eight different palmi, varying from 22.3 to 29.2 centimeters. The values listed below for the various units mentioned by Biringuccio are the Florentine ones, which were also used in Siena and Tuscany: [ ]

Jan 1, 1942

H. RIES, Ithaca, N. Y.-The part of Mr. Fiske's paper that interests me especially is that portion dealing with the raw materials, and the tests that were applied to the raw materials in order to determine their value in advance, if possible, because that, I believe, is a step in the right direction. For a number of years I have done my best to persuade different consumers of clay to develop standard methods for testing raw materials. We have in this country a large variety of clays which can be used for a great many different purposes, but in many cases the consumers either have no standard methods for determining the value of those clays in. advance, or if they have they do not publish them; consequently it often puts the clay miner at a disadvantage. If, for example, manufacturers of different types of refractory materials would state publicly just what physical tests their raw materials have to meet, it would, I believe, help them to find more easily the materials that they are looking for, and the clay producer would also be benefited. It would also encourage him to have his clays tested in advance, so that samples could be accompanied by certificates of physical tests that would be of convenience to the manufacturer. At the present time, in this country there are certain types of clay which seem to be rather scarce. There apparently are not many deposits of clay that are exactly suited for the manufacture of zinc refractories. So, too, there are not many deposits of clay that are suited for the manufacture of glass-pots, or the blocks for glass tank furnaces, or clays that can be used for graphite crucibles. Now, in many cases, no standard series of tests has been developed. I am also gratified to see that Mr. Fiske considers the tensile strength. tests of value. Some years ago the American Ceramic Society appointed a committee to draw up a series of recommendations covering standard tests. These recommendations were especially for the use of State geologists and the U., .S. Geological, Survey. Among the tests that were considered was the tensile-strength test, which Mr. Fiske has mentioned in his paper. Unfortunately, a majority of the committee turned it down, and the test was therefore not officially approved, but two of us, who formed the minority, believed in it. Since then the other members of the Committee have come to see that that is an important test to make and Mr. Fiske has emphasized it in his paper.

Jan 1, 1918

By P. R. Hanes

A description of the methods used in driving two tunnels, 2 miles long each, one a 9-ft. and the other a 19-ft. diameter section, for the Owyhee Irrigation Project, Oregon. One heading of the smaller tunnel was driven 1315 ft. in 73 shifts in one month and 10,966 ft. of this section completed in ll½ months using two shifts for eight months and three shifts the rest of the time. This is a good illustration of the proper use of a mechanical shovel and the importance of careful selection of supplernentary equipment to secure best results. Large cars, speedier and heavier locomotives, 36-in. gage track of 45-lb. rail, and a good switching method increased actual shoveling time and cut down muck removal period about 45 minutes from average. The larger tunnel, after trying out standard electric revolving shovels of both the rail mounting and caterpillar tread types, was excavated with a mechanical mucker. This is the first time that a tunnel of so large a section has been handled this way. This record work was accomplished without drill carriages.

Jan 1, 1934

By L. S. Richardson, N. J. Grant

REACTIONS of oxygen and nitrogen at low pressures with titanium have recently been studied by a number of investigators.1-3 Gulbransen and Andrew' noted that the reaction with nitrogen followed the parabolic rate law whereas the reaction with oxygen deviated slightly from this law in the temperature range 300° to 800°C. In the work reported here, commercial titanium (75 A) was used as the test material. Cylinders 2.5 in. long and 0.25 in. in diameter were machined from heavier bar stock. The test pieces were given a metallographic finish, immersed for 30 min in cold concentrated HC1, washed in water, then acetone, and dried with lint-free cloth. Reaction rates were determined in a modified Sieverts type apparatus by measuring the decrease in gas pressure of the reacting gas contained in a constant volume. The amount of gas added could be measured in a calibrated gas burette to an accuracy of 0.01 mm. During the course of a run the temperature never varied by more than 10°C and then only for brief moments. After placing the specimen in the furnace, the system was first evacuated for 12 hr at room temperature, and then flushed with purified argon five times, adsorbed gases being discharged during this period from the glass system with a high frequency spark coil. The flushing and discharging were repeated at 400°C. This rather involved procedure was found necessary after a number of trial runs indicated extraneous effects traceable to the system. Reaction periods up to 2 hr were used, at initial gas pressures of 0.2 to 0.5 atm. Experimental Results Fig. 1 shows the decrease in oxygen pressure for tests at 0.5 atm at various temperatures as a function of the square root of the time. Deviations from linearity are minor and the parabolic rate law is obeyed. Fig. 2 shows the same plot for the nitrogen reaction. A definite deviation from linearity is noted; however, it is probable that the higher initial rates are caused by the presence of small amounts of oxygen contamination, the initial faster rate changing to the slower rate after about 5 to 10 min. Calculations of the rate constants were made on the basis of the latter portion of the curves. The parabolic rate law constants calculated from these curves are shown for oxygen and nitrogen in Fig. 3. In spite of some scatter the average curves are quite definite. Changes in gas pressure of the order of 20 pct did not result in a measurable change in the rate law constants. The activation energy for the oxygen reaction was calculated to be 47,400 cal per mol (above 700°C), which is not in agreement with the value quoted by Gulbransen and Andrew' for lower temperatures, their value being 26,000 cal below 600°C. The activation energy for the nitrogen reaction was calculated to be 45,400 cal per mol above about

Jan 1, 1955

The Pueblo Viejo Mine, a 7, 250 mtpd (8,000 stpd) gold-silver cyanidation plant built by Rosario Dominicana S. A., was described in Volume I of this monograph. At the time of writing that volume, Pueblo Viejo had not yet gone on-stream and operating data or costs could not be presented. Since that time this information has been obtained and several interesting modifications and an expansion have been made to the plant. Because Pueblo Viejo is the largest open-pit gold mine in the world and one of the world's leading gold-silver operations with production of approximately 31 kg (1,000 oz) gold and 125 to 155 kg (4,000 to 5, 000 oz) silver per day, the authors have updated the previous data and flow sheet. The Dominican Government, which held a 4670 interest in Rosario Dominicana S. A., completed purchase of the mine to gain full control in 1979. Rosario Resources will continue to manage the mine, at least until the end of 1980. Gold was produced at Pueblo Viejo almost 500 years ago with initial production in the year 1505. Rosario Resources became interested in the property in 1969 and found surface oxidation had rendered the upper portion of the ore body amenable to direct cyanide treatment. The treatment of the underlying gold-bearing sulfide zone is still undergoing metallurgical studies. The ore is considered to be a laterite; and because there appeared to be few boulders in the ore zone, only a 400 m (16 in. ) square grizzly was initially installed ahead of the mills when the plant went on-stream in late 1974 at a design capacity of 7,250 mtpd (8,000 stpd). Operation also proved the ore to be harder than was originally anticipated. During 1967 a 1. 25 m by 1. 5 m (48 in. by 60 in. ) jaw crusher was installed to -feed the 1, 000 mt (1, 100 st) mill bin. Minus 200 mm (8 in.) crushed ore is fed directly to two 5.5 m by 1. 8 m (18 ft by 6 ft) semi-autogenous mills re-powered with 750 km (1,000 hp) motors and 50 mm (2 in.) grates. Each mill product is screened at 13 mm (1 /2 in.) by a vibrating screen. Screen oversize from each mill is combined on a single return belt equipped with a magnetic head pulley for grinding ball removal. The non-magnetic oversize is then split into two fractions for return to the primary mills. Originally, a minus 6 mm (1/4 in ) product was made on each screen and fed to a 300 kw (400 hp) 2.6 m by 3. 7 m (8-1/2 ft by 12 ft) regrind mill. During a plant expansion in 1978, an intermediate mill of 746 kw (1,000 hp) was installed to operate in open circuit on the combined primary mill

Jan 1, 1981

By Thomas R. Stauffer

The principle that conventional schemes for taxing petroleum or mineral resources are "inefficient" is illustrated using simulation calculations tested against an "ideal" system. Inefficiency is defined as the relative success in maximizing expected government revenues from the resources. Most systems fail because: 1) they leave oil in limbo, i.e. unproduced because of excessive fiscal burden; or 2) they unnecessarily increase the variance in the explorationist'c, rate of return by undertaxing large fields and overtaxing smaller but infra-marginal fields. This increases his discount rate and reduces taxable surplus. An "ideal" tax system is specified which maximizes government revenues while minimizing risk to the operator. Two criteria are developed: 1) the tax falls to zero on fields which yield only the minimum necessary rate of return ("marginal" fields); and 2) the after-tax present value of all fields is the same for all fields above a threshhold size. In particular, marginal fields, while contrib- uting little to expected values, do contribute to reducing variance and hence risk praemia by distributing the exploration costs over a higher probability of successful outcomes.

Jan 1, 1982

By D. G. Westlake

The electrical resistance of a series of V-H alloys (0 to 3.5 at. pct H) has been measured over the temperature range G° to 360°. Interstitial impurities made contributions to the residual resistivity, but not the ideal resistivity. The contribution of hydrogen in solid solution is expressed by Ap = 1.12 microhm-cm per at. pct H; but the contribution of precipitated hydride was negligible. A portion of the so1vu.s for the V-H phase diagram is presented. The solubility limit is given by In N (at. pct H) = (5.828 i 0.009) - (2933 i 44)/RT. Comparison of critical temperatures joy hydride precipitation and published critical temperatures for hydrogen embrittlement suggests the two are related. ThiS study was initiated as part of an investigation of the mechanism by which small concentrations of hydrogen embrittle the hydride-forming metals at low temperatures. It has already been shown that, in the case of hcp zirconium, a reduction in ductility accompanies the strengthening resulting from precipitation of a finely dispersed hydride phase.''' Our attempts to detect a similar precipitation of a second phase at low temperatures in V-H alloys by transmission electron microscopy have been thwarted because we have been unable to prepare thin foils that are representative of the bulk material with respect to hydrogen concentrati~n.~'~ The present investigation establishes the solvus of the V-H system at subambient temperatures. Subsequently, we hope to be able to determine whether the embrittlement temperature is related to the critical temperature for precipitation of the hydride in a given V-H alloy. veleckis5 has proposed a partial phase diagram for the V-H system based on extrapolations of the pressure-composition relations he measured at higher temperatures. Kofstad and wallace' conducted a similar study of single-phase alloys but did not attempt to establish the phase diagram. Zanowick and wallace' and ~aeland' have studied a portion of the phase diagram by X-ray diffraction, but they investigated no alloys in the hydrogen concentration range 0 to 3 at. pct, the range of interest to us. EXPERIMENTAL PROCEDURE The vanadium was obtained from the Bureau of Mines, Boulder City, Nev., in the form of electrolytic crystals. The analyses supplied with them listed 230 ppm by weight metallic impurities, 20 ppm C, 100 ppm N, and 290 ppm 0. The crystals were electron-beam-melted into an ingot that was rolled to 0.64 mm. Strips, 60 mm long and 4.2 mm wide, were cut from the sheet, and both rolled surfaces were ground on wet 600-grit Sic paper to produce specimens 0.4 mm thick. They were wrapped in molybdenum foil, vacuum-encapsulated in quartz, and annealed 4 hr at 1273°K. The specimens were annealed in a dynamic vacuum of 2X lo-' Torr for 30 min at 1073°K for dehydrogenation, and charged with the desired quantity of hydrogen by allowing reaction with hydrogen gas at 1073°K for 2 hr and cooling at 100°K per hr. Purified hydrogen was obtained by thermal decomposition of UH3. Sixteen specimens were studied: two contained no hydrogen and the others had hydrogen concentrations between 0.5 and 3.5 at. pct (hydrogen analyses were done by vacuum extraction at 1073°K). Electrical resistances were measured by the four-terminal-resistor method on an apparatus similar to the one described by Horak.~ The specimen holder was designed so that both current and potential leads made spring-loaded mechanical contact with the specimen. The potential leads were 30 mm apart, and the current leads were 55 mm apart. The current was 0.10000 amp. We used the following baths for the indicated temperature ranges: liquid nitrogen, 77°K; Freon 12, 120" to 230°K; Freon 11, 230" to 290°K; and ethanol, 290" to 340°K. Temperatures lower than 77°K were achieved by allowing the specimen to warm up after removal from liquid helium. Temperatures above 77°K were measured by a calibrated copper-constantan thermocouple (soldered to the specimen holder) and below 77°K by a calibrated carbon resistor. The temperature of the bath changed less than 0.l0K between duplicate measurements of the resistance. RESULTS AND DISCUSSION Typical plots of resistivity p vs temperature T are shown in Fig. 1. In the interest of clarity, only five curves are presented and the data points have been

Jan 1, 1968

By E. T. Turkdogan, P. Grieveson

Experimental results are presented for the rate of solution of nitrogen in a iron in the temperature range 750° to 873°C and in 6 iron in the temperature range 1410° to 1470°C. It is shown that the rate controlling process is diffusion of nitrogen into the iron. The diffusiting of nitrogen in a and 6 iron is derived from the results, and the temperature dependence of the diffusivity is represented by the equation D = 7.8 x e- 18,900/RT sq cm per sec. The solubility of nitrogen in a and 6 iron, in equilibrium with 1 atm pressure of nitrogen, has been measured. Using these results and other available data, it is found that the variation of the logarithm of nitrogen solubility with the reciprocal of absolute temperature is nonlinear. In an Appendix, some results of Darken and Smith are presented for the rate of solution of nitrogen in iron using ammonia + hyidrogen mixtures. These data also support the view that diffudsion of nitrogen in iron is the rate-controlling process when ammonia + hydrogen mixtures are used. A considerable effort has been made to obtain data on the solubility1-5 and diffusivity of nitrogen in a iron6-l2 because an understanding of the effect of nitrogen on the properties of steel must be based on an accurate knowledge of the properties of nitrogen in pure iron. However, no information is available concerning the kinetics of solution of nitrogen in a and 6 iron. Recently the authors13 have investigated the rate-controlling mechanism operating in the kinetics of solution of nitrogen in y iron. This study was directed to determine the rate-controlling processes for similar reactions with a and 6 iron as well as to establish values for the solubility of nitrogen in equilibrium with nitrogen gas in a and a iron. EXPERIMENTAL The procedure used in experiments to determine the rate of solution in cylindrical iron rods was the same as that described in a previous communication.13 Ferrovac E grade iron used in all experiments contained the following impurities in weight percent: C, 0.005; Mn, 0.001; P, 0.002; S, 0.006; Si, 0.006; Ni, 0.025; Cr, 0.002; V, 0.004; W, 0.02; Mo, 0.01; Cu, 0.001; Co, 0.01; 0, 0.007. After cleaning the surface, the iron rods were treated in an atmosphere of purified hydrogen for 17 hr before the reacting gas was introduced for known experimental times. After quenching, the samples were sectioned radially and analyzed for nitrogen. In addition to experiments using rods, iron foils were used in the measurements of solution rates of nitrogen in a iron. The foils of two different thicknesses were prepared by cold rolling Ferrovac E grade iron cylindrical rod to 0.051 and 0.152 cm. Foil samples were used in a rectangular form 5 cm long and 1.25 cm wide. The specimens were thoroughly cleaned of surface oxide with fine emery cloth and degreased with carbon tetrachloride immediately before entry into the furnace. The experimental procedure was the same as that used in the study with rods. At the completion of an experiment, the foil samples of the nitrogenized iron were analyzed for nitrogen after discarding 0.3 cm from the perimeter of the specimen. Iron foils were nitrogenized and denitrogenized in the a and 6 range with a gas mixture of 95 pct N and 5 pct H for times varying from 5 min to 2 hr. Results obtained for the average composition of nitrogen in iron for these experiments are presented in Fig. 1. Prior to the denitrogenization experiments, the samples were saturated with nitrogen at 1000°C and 0.67 atm N, giving a uniform nitrogen concentration of 0.0204 pct. According to the known a-y phase boundary in the Fe-N system,14 this composition lies within the ferrite region at temperatures 750" to 850°C. Use of this initial nitrogen content insured that reaction occurred between the gas and a single solid phase, a iron. Examples of the results for the mean concentrations of nitrogen in cylindrical iron rods, 0.356 cm radius for both the a and 6 ranges are given in Fig. 2. Typical examples of the results obtained for the radial distributions of nitrogen in rods are presented in Fig. 3. It appears that the results for radial distributions can be extrapolated to constant surface compositions which agree with the equi-

Jan 1, 1964

By J. E. Lamar

THAT Illinois is an important mineral producing state is well known. A value of over $237,000,000 for the mineral products in 1926 indicates the magnitude of the industries. Coal mining is the largest mineral industry, and the value of its product was about 63 per cent of the total mineral production of the state. Oil and gas constituted about 8 per cent and the non-metallic minerals about 29 per cent. This 29 per cent represents the production of a varied group of mineral industries of wide geographic distribution through the state.

Jan 1, 1929

By Frank Firmstone

Discussion of the paper of John B. Dilworth, presented at the Pittsburg meeting, March, 1910, and printed in Bulletin No. 35, November, 1909, pp. 1041 to 1043. FRANK FIRMSTONE, Easton, Pa. (communication to the Secretary*) :-Mr. Dilworth's formulas and tables are of course correct, and the extinction will occur as calculated, provided the money periodically set aside for sinking-fund be really invested. and the interest compounded as assumed in the calculation. Actually, in almost all cases, such funds are used "in the business," in which case, in addition to the periodical charges for principal of the fund, additional charges must be made at the end of each period to cover the interest and compound interest on previous charges. The periodical charge for sinking-fund thus becomes a varying and continually increasing one until the date of extinction. On many accounts it seems more natural and convenient to make the extinction by a fixed periodical charge under the legal rule for partial payments, namely, that each payment should apply first to the interest due at the date of payment;: and any remainder, after this is satisfied, be deducted from the principal before the interest for the next period is calculated. The formula below is convenient for such calculations S, Principal to be extinguished. Q, Periodical payment or charge for sinking-fund. B, Balance unpaid at date of nth payment, but before that payment is made. r, Rate of interest per period per cent. n, Number of payments or periods. Then, B=S(1+r)n-Q(1+ r)n-(1+r) Received July 27, 1910.

Apr 1, 1911

By G. Y. Chin, M. T. Dolan, W. L. Mammel

We have obtained by computer methods the solutions of the Taylor analysis1 for axisymmetric flow in bcc metals. Four modes of slip have been treated in detail:2-4 (111), {112}(111), {123}( 111), and a mixture of all three. In addition to obtaining anisotropy of strength data for randomly oriented or textured polycrystalline material,4 we have also obtained the lattice rotation resulting from slip on the predicted systems. The patterns of lattice rotation are essential to an improved understanding of texture development during deformation. The present note shows the results of lattice rotation for 5 pct axisymmetric compression, for fifty-two axial orientations distributed at 5-deg intervals throughout the standard stereographic triangle. The data are presented in Figs. 1 to 4 for the four modes of slip. The lattice rotation is indicated by a vector, the ends of which correspond to the positions before and after the deformation. The different vectors emanated from a given orientation represent different combinations of five slip systems that satisfy Taylor&apos;s minimum shear criterion.&apos; Fig. 1 shows the results for {110}< 111> slip. They are similar to those obtained by Bishop5 for the case of (111 )(110) slip in axisymrnetric tension, since in axisymmetric flow the sense of lattice rotation for {111)( 110) in tension is the same as that for (110) (111) in compression. The pattern of lattice rotation may be divided into three regions: region A in which the rotation is toward [100]; region B, toward [lll]; and region C, toward either [ loo] or L lll]. Although some slip combinations in region C lead to [1101, the latter is not stable as continued activity of the same combinations will eventually move the axis toward [loo] or Llll]. It may also be noted that [loo] is itself not stable. However, close inspection of the vectors in region A shows that it is impossible for an axial orientation within A to rotate outside its boundary. Hence after heavy compression, all orientations from A and some from C are expected to form a diffuse band in the [100] vicinity. By far the largest region is B. Here all orientations rotate to [lll], which is a truly stable position. Thus the [111] texture component is expected to be rather sharp. For the case of (112 }( 111) slip, Fig. 2, region C is enlarged at the expense of A, with B about the same as for {110}( 111) slip. A significant difference, however, is that [loo], as well as [Ill], is now truly stable. Fig. 3 shows the results of slip on {123}( 111) systems. Region B is substantially enlarged at the expense of C, with A being intermediate in size between the {110}(111) and {112}(111) cases. Like the case of {110)( 111) slip, [100] is itself unstable. However, the lattice rotations here are confined to less than 5 deg; hence it may be considered "stable" for practical purposes. Finally, Fig. 4 shows the results of mixed slip. Here region B is the largest, and C the smallest, of all the cases considered. Both [loo] and [ill] are stable. The behavior of the three corner positions is, in fact, identical to the case of {112)( 111) slip, Fig. 2; it turns out that in these positions for the mixed slip case, all the active slip systems (based on Taylor&apos;s criterion) belong to pure {112}( 111) .4 In summing up the results for the four modes of

Jan 1, 1968

By Stephen G. Wright

Jan 1, 1985

By F. L. Wolf

THE tests here described were made to obtain information regarding costs, efficiency, etc. of baking cores in an oil-fired oven, and two electric ovens, which were installed, early in 1920, in the core room of The Ohio Brass Co. and were used almost continuously during the rest of that year. Operating costs were rather high so a complete test was undertaken early in 1921. The ovens will be referred to as Nos. 1, 2, and 3. Nos. 1 and 2 are electric ovens of different makes while No. 3 is an oil-fired oven made by the firm that made No. 2. The three are equipped with similar ventilating devices. They have full-height doors at front and rear. The cores are placed on iron racks, which are lifted by Cowan trucks and rolled into the ovens through the front doors. When baked, they are removed through the rear doors. Fig. 1 shows the general plan of the electric ovens while Fig. 2 shows the plan of the oil-fired oven. Oven No. 1 is 91 in. (231 cm.) wide, 83 in. (210 cm.) high, and 79 in. (200 cm.) deep, inside measurements. The walls are constructed in, panels about 18 in. (46 cm.) wide and 4 3/16 in. (10.6 cm.) thick, packed with blocks of insulating material and covered with sheet iron. The concrete floor on which the ovens set is 13 in. (33 cm:) thick. A recess about 5 in. (13 cm.) deep was cut in the floor to provide room for the heating units. Channels and plates supported. on I beams serve as&apos; supports for the trucks and racks. The ventilating system consists of a Sirroco No. 1 ½ fan, connected so as to draw air from the top of the-oven or from the room, through damper C, and to deliver it either to the bottom of the oven or to the floor; the delivery is controlled by the vane A. The fan and pipes are covered with ¼ n. (6.3 mm.) asbestos cement lagging.

Jan 4, 1922

By W. H. Blauvelt

The only way in which the difficult problems of classification of coal for the manufacture of by-product coke can be solved is to analyze them by the use of scientific data. It is very easy to adopt classifications for coal for the manufacture of by-product coke along certain lines; we can easily say that for a certain class of metallurgical operation coke made from bituminous coal must not contain more than so much sulfur or more than so much ash and should yield certain returns in the by-products, tar, ammonia, benzol, gas, etc. Those points we are fairly clear on and I think it is hardly worth while to discuss them because I presume that they are familiar to most of us who have any occasion either to make coke or to use it. But there is a field in the manufacture of coke which we know very little about. For example, we are operating a plant on a certain mixture of coal. Suddenly our blast-furnace man or the user of the coke tells us the coke is not as good as it was before. The coke is analyzed and the coal is analyzed. Everything seems to be about the same as it was— the ash is the same, there is no more sulfur, and so on—but the coke, for the use to which it is put, particularly in the blast furnace, is wrong. What happens? The management decide to try a slightly different coal mixture. They do not necessarily raise the total hydrocarbons, the volatile matter in the mixture, nor change the sulfur or the ash, but they do make a change which improves the value of the coke for metallurgical use. The reason for this difficulty, as I see it, is the " combustibility " of the coke—I hesitate to use the word, but it is the best one I have available. Combustibility of Coke We know now that the combustibility of coke is a very vital point in many metallurgical processes and I think one of the most notable instances of the proof of this is the experience of the Carnegie Steel Co. in the production of coke at its Clairton plant. The history of that

Jan 1, 1930

By John D. Sullivan

MAJOR technical advances seldom occur in a single year, and this is especially true with aluminum and magnesium where marked improvements in metallurgical processes and products took place during the war years. Nevertheless, the light metals and alloys, particularly aluminum, are advancing in commercial importance and are finding their niche in industry. New applications during the year have resulted from a better over-all knowledge of properties, handling, etc., rather than from revolutionary new developments.

Jan 1, 1948

[A Aamodt, H. C., A55 C Sales, Great Lakes Carbon Corp., 18 E. 48th St., New York, N.Y. Aamot, Olav Crone, M29 2126 M4, Galveston, Texas Aaronson, Hubert I., M47 E Prin Res Engr, Ford Motor Co., Met. Dept., Sci. Lab., Engrg. Staff, P. O. Box 2053, Dearborn, Mich. Aase, Glenn D., M54 D Prin Engr, Air Pollution Control Dist., 1480 Mission St., San Francisco 3, Calif. Abbett, W. A., Jr., M56 8629 Beverly St., Duluth 8, Minn. Abbey, Robert G., M56 138 Dartmouth Rd., Bala Cynwyd, Pa. Abbott, A. G., Jr., J52 E Test, Dev Engr, Chrysler Corp. Missile Div., P. O. Box 2628, Detroit 31, Mich. Abbott, Mark L., A58 Rep, General Refractories Co., 208 S. LaSalle St., Chicago, Ill. Abbott, W. K., J58 E Dev Met, Int&apos;l Nickel Co., Inc., 67 Wall St., New York 5, N.Y.]

Jan 1, 1961

THOSE NOT MARKED ARE MEMBERS; MARKED THUS t ARE ASSOCIATES. HEAVY-FACED TYPE SIGNIFIES HONORARY MEMBERSHIP. JUNIOR MEMBERS ARE MARKED II. THE FIGURES AT THE END OF THE ADDRESS INDICATE THE YEAR OF ELECTION. AARONS, J. BOYD, Genl. Mgr., Chaffers G. M. Co., Boulder City, West. Australia. &apos;05 ABADIE, EMILE R., Min. Engr Box 291, Porterville, Tulare Co., Cal. &apos;76 ABBOTT, CLARENCE E., Genl. Supt., Iron Mines Div., 1405 Minnesota Ave., Bessemer, Ala. &apos;04 ABBOTT, J. W., Min. Engr., "St. Omer," 123 N. Grand Ave., Los Angeles, Cal. &apos;94 ABBOTT, Louis BENJAMIN, Chief Engr., Consolidation Coal Co., Elkhorn Div., Jenkins, Ky. &apos;15 ABBOTT, ROBERT R., Met. Engr., Peerless Motor Car Co., Cleveland, Ohio. &apos;12 ABE, ASAKA Yamagano G. M., Satsuma-Gori, Satsuma, Japan. &apos;14 || ABRAHAMS, A. I., Student 1391 Madison Ave., New York, N. Y. &apos;14 tACKER, E. O&apos;C., Met Bethlehem Steel Co., Bethlehem, Pa. &apos;86 ACKER, LOUIS K., JR., Min. Engr 565 Highland Place, Bellevue, Pa. &apos;08

Jan 1, 1917

By K. J. Gill, P. Chiotti, J. T. Mason

Thermal, metallographic, and vapor pressure data were obtained to establish the pkase boundaries and the standard free energy, enthalpy, and entropy of formation for the compounds in the Y-Zn system. Three coinpounds with stoichiometric formulas of YZn, YZn2, and Y2Zn17 melt congruently at 1105", 1080°, and 890°C, respectively. Four compounds with stoiclziometric formulas of YZn3, YZn4, YZn5, and YZn,, undergo perztectic reactions at 905", 895", 870º, and 685ºC, respectively. Three eutec-tics exisl in this system with the .following eutectic temperatures and zinc contents in wtpct: 875ºC, 23.2 Zn; 1015ºC, 51 Zn; 865ºC, 82 Zn. The YZn, pkase undergoes an allotropic transformation. In the two phase YZn2 -YZn alloys the trans.formation gives a weak thermal arrest at 750°C, whereas in the two phase YZn2-YZn3 alloys no thermal arrest is observed and the transformation occurs over a temperature range below 750°C. At 500°C the free mzergies of formation per lnole vavy from —18,090 for YZn to —53,430 fov YZr11 and corresponding enthalpies vary from -24,050 to -92,080. The free energies and enthalpies per g atom as a function of composition show a maximum for the YZn2 phase; the 500°C values are -9580 and -13,180, vespectively. 1 HE only information found in the literature on Y-Zn alloys was the observation reported by Carlson, Schmidt. and speddingl that Y-20 wt pct Zn forms a low melting alloy. The alloy was produced by the bomb-reduction of YF3 and ZnF2 with calcium in an investigation of methods for producing yttrium metal. The solubility of yttrium in zinc has been determined by P. F. woerner2 and reported by Chiotti, Woerner, and Parry.3 In the temperature range 495" to 685°C the solubility may be represented by the relation In these equations N represents atom fraction of yttrium and T is the temperature in degrees Kelvin. The purpose of the present investigation was to establish the phase diagram for the Y-Zn system and to determine the standard free energy, enthalpy, and entropy of formation for the compounds formed. MATERIALS AND EXPERIMENTAL PROCEDURES The metals used in the preparation of alloys were Bunker Hill slab zinc, 99.99 pct pure, and Ames Laboratory yttrium sponge. Arc-melted yttrium buttons contained the following impurities in parts per million: C-129, N-12, 0-307, Fe-209, Ni-126, Mg-13, Ca < 10, F-105, and Ti < 50. Some of the alloys containing 70 wt pct or more of Zn were prepared from yttrium containing 5000 ppm Ti as a major impurity. Tantalum containers were found to be suitable for all alloys studied and were used throughout the investigation. The pure metals, total weight about 30 g, were sealed in 1 in. diam tantalum crucibles by welding on preformed tantalum covers. A 1/8 in. diam tantalum tube was welded in the base of each crucible for use as a thermocouple well. Welding was done with a heli-arc in a glove box which was initially evacuated and filled with argon. The sealed crucibles were enclosed in stainless steel jackets and heated in an oscillating furnace at temperatures up to 1150°C. Homogeneous liquid alloys were obtained within a half hr at these temperatures except for alloys containing less than 20 pct zinc. The latter alloys were held at 1000º to 1100°C for 2 to 3 days in order to obtain equilibrium. After the initial equilibrations the tantalum crucibles containing the alloys were removed from the steel containers and used directly for differential thermal analyses. Further annealing heat treatments for alloys in which peritectic reactions were involved were carried out in the thermal analyses furnace. After thermal analyses the tantalum crucibles were opened and the alloys sectioned and polished for metallographic examination. In the following discussion alloys referred to as "quenched" were obtained by quenching the sealed stainless steel jacket containing the tantalum crucible and alloy in water. The differential thermal analyses apparatus used was a modified version of the one described in an earlier paper., The graphite crucible was replaced by an inconel crucible, the nickel standard and sampie container were separated by a 1/8 in. MgO plate, no getter was used, and provisions were made to

Jan 1, 1963

By Rollin A. Pallanch

THE Midvale mill of the United States Smelting Refining and Mining Company is situated on a flat site whose elevation is 50 ft above that of the Jordan River. Tailings are impounded in the area between the river and the flat upon which the mill and railroad switchyard are located. The water supply is pumped from the Galena canal which leads from the river at a point some ten miles to the south. The mill has a present capacity of approximately 1700 tons daily. It started out originally in 1926 as a 750 ton three-unit plant. The tonnage was gradually increased to 1200 tons by 1934, and in late 1935 a fourth unit was added. The accompanying flowsheet shows the principal equipment and how it is utilized. The ore is principally sulphide with varying degrees of oxidation, with individual lots ranging widely in both precious and base metal content. In each of the four individual units of the mill there will often be mixtures of as

Jan 1, 1948