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By G. W. Form, W. A. Spitzig

The effects of hydrogen and vacuum shtering treatments on the physical and mechanical properties of arc plasma-sprayed tungsten were inuestigated. Temperatures examined ranged from 3000" to 4000°F in vacuum and 2000" to 3000°F in hydrogen for both single and duplex sintering cycles. Densities of 92 pct of theoretical density were obtained when a long-time hydrogen treatment at 2000°Fpreceded sintering in vacuum at 4000°F for 4 hr. This cycle also produced the highest ualues for modulus of rupture and bend angle. The results of this investigation point out the desirability of using a low-temperature long-time hydrogen treatment prior to a high-temperature vacuum sinter for arc plasma-sprayed tungsten. ADVANCES in the development of arc plasma-generating equipment have provided a high-temperature heat source that makes the fabrication of tungsten shapes possible by a metallizing process. Tungsten in the as-sprayed condition is very brittle. It has a density between 80 and 85 pct of theoretical density, a lamellar structure with elongated pores, and a high interstitial impurity content. To improve these properties, sintering treatments can be applied to the as-sprayed material, similar to those used for the densification of compacted tungsten powder. However, in view of the differences in the density and microstructure of as-sprayed tungsten as compared with compacted tungsten, responses to sintering were expected to be different. EXPERIMENTAL PROCEDURES The tungsten powder used in this investigation had a particle size varying from 3 to 13 p with an average diameter of 8p. The impurity level was less than 0.1 pct. The arc plasma spraying was done with an F-40 Thermal Dynamics Corp. plasma jet. Spraying was performed in air and thus required cooling of the substrate by an air blast in order to minimize oxidation. The spraying parameters employed in the fabrication of all specimens are listed below: Power input, kw 12 Arc-gas flow, cfh 95N2 + 5H2 Powder feed rate, g per min 33 Powder carrier gas flow, cfh ION, Spray distance, in. 3 Traverse rate, in. per min 30 Mandrel speed, rpm 100 Nozzle orifice, in. 7/32 These values of the spraying parameters correspond to optimum conditions ascertained in a previous study. Sintering was conducted at 3000°, 3500, and 4000°F in vacuum (< 0.1 Hg), and at 2000 and 3000°F in hydrogen. Duplex sintering treatments investigated are listed in Table I together with the designations that will be used for reference throughout this paper. The samples were fabricated by spraying onto a copper mandrel which was removed prior to sintering. The specimens used for the sintering analyses had the shape of small hollow truncated cones 1 in. high with an inside diameter varying from 0.500 to 0.125 in. and a wall thickness of 1/8 in. Specimens for bend testing were taken from hollow hexagonal prisms 1-1/2 in. high with a 1-in. diam across the flats and a wall thickness of 1/8 in. The bend-test specimens were ground to the dimensions 0.085 by 0.350 by 1-1/2 in. Prior to bend testing 0.0025 in. of stock was removed from each surface by electro-polishing. Density measurements were made by the water-displacement method. In addition, a porosimeter was used to determine the amount of interconnected porosity for representative samples. Strength and ductility were determined from recorded values in transverse bending using a cross head speed of 0.020 in. per min. The load was applied at the midpoint of a 1-in. span. The deflection data reported herein refer only to the plastic portion of the total deflection. RESULTS AND DISCUSSION The as-sprayed samples had a density corresponding to 83 pct (l pct) of the theoretical density of tungsten. Fig. 1 shows a representative as-sprayed tungsten structure.

Jan 1, 1964

By W. Evans, C. E. Ells

The agglomeration of hydrogen in pure aluminum and A1-Mg alloys has been studied through use of hydrogen introduced into the metal by cyclotron proton irradiation. Both the growth and dispersal of the agglomerates have been followed by metal-lographic techniques. During the cyclotron irradiation, agglomeration occurs at temperatures i 100°C for hydrogen concentrations as low as 1 ppm. On heating at elevated temperatures, 300°C to 600°C, intragranular agglomerates first coarsen and then disperse. The agglomerates formed at grain boundaries are much larger than the intragranular agglomerates; with hydrogen concentra- tions > 10 PPm, heating for 1 hr at 500°C results in extensive grain-boundary cracking. The hydrogen agglomerates have been shown to inhibit grain growth, but no inhibition of recrystallization has been observed. The ability of hydrogen to enter aluminum at a free surface, combined with its high-diffusion rate at elevated temperatures, accounts both for growth and dispersal of the agglomerates. Irradiations at elevated temperatures give results consistent with the explanation proposed for agglomerate behavior on post-irradiation heating. 1 HE formation of hydrogen-filled bubbles, or blisters. in aluminum and its alloys has been studied for over&apos; thirty years. The work up to 1952 has been reviewed by Kostron&apos; and since then Ransley and

Jan 1, 1963

By Thomas L. Garwood, F. C. Menk

IT is generally accepted that no method of coal cleaning except froth flotation is effective in cleaning dust. In the majority of coals mined in the United States the dust sues contain a high percentage of impurities, hence the removal of the dust from the coarse sizes lowers the impurity content of these sizes. Dedusted coal is desired as a means of providing a better feed to cleaning plants because of increased efficiency in I both dry and wet plants. In dry-cleaning plants, a dedusted feed makes for a pervious and uniform bed. With a dusty feed the fines tend to segregate in the feed stream and pass en masse over the air separators, causing a lack of uniform aeration and fluidity of the bed necessary to efficient cleaning. In wet-cleaning plants dedusting of the feed often decreases the sludge problem to the point of eliminating the necessity of wasting wash water. It may be advantageous to eliminate sludge-settling equipment in favor of dedusting equipment, to provide the advantages of a dedusted feed to the wet-washing process. Dedusting advantages may include: (1) the removal of fusain, especially advantageous in plants washing coal intended for metallurgical coke; (2) prevention of the gradual build-up of solids in the wash water, with a consequent variation in the washing ability of the system; (3) prevention of the loss of dust to the sludge ponds, providing instead a fuel for local consumption or special markets. DEDUSTING The practice of dedusting, sometimes called aspirating, has presented a problem in disposing of the dust and intermediate small sizes recovered in the process. It has been found that no difficulty is experienced in disposing of the intermediate sizes, since they are free of fine dust and burn freely on grates built for small coal. They handle well, flowing freely from bins and hoppers and into conveyors, and pulverize easily. They have a low angle of repose. In tests made on this size as a feed to coke ovens, the results have been excellent, in that the natural breakdown of coal in handling and shooting in the mine gives this small-size coal good coking characteristics-producing a strong, fingery coke structure. Deduster dust from Illinois coal has been

Jan 1, 1950

By André G. Journel

Geological study of the Prony Nilaterite (New Caledonia) began in 1969 and included drilling, geological mapping and laboratory studies. The deposit is the product of weathering of basic rocks. From top to bottom, the following zones can be distinguished: a compact ferruginous cover; ore associated with yellow laterite, containing 1.0-1.5% Ni and low in impurities (SiO2, Mg); an intermediate silicated ore containing 1.3-2.0% Ni and higher percentages of impurities; garnierite ore much richer in nickel (2-4%) but high in SiO, and Mg contents (Mg up to 20%) ; and parent rock, largely peridotites. Distinction between types of ore is essential because the high grade ore (silicated and granierites) is penalized for its high Mg contents that demand additional acid treatment. All studies made distinguish two types of ore, laterite and silicated.

Jan 10, 1973

The first production on the Island of Trinidad was discovered 29 years ago; 13,275 acres were proved for oil and gas to the end of 1937, and 145,076,700 bbl. was produced from 2661 wells, or 10,928 bbl per acre. The production of oil in 1936 was 13,237,030 bbl. and in 1937 a new peak of 15,498,350 bbl. was reached. During November 1937, the daily average production was 43,350 bbl., or 35 bbl. per well, while the maximum gas production was 45 million cubic feet daily. Two hundred fifty wells were completed during 1937 and 15 abandoned. At the end of last year, 800 wells had been temporarily shut down, 1235 were producing oil and gas, and 2 were producing gas only. Six hundred seventy-nine dry wells had been drilled to the end of 1937. At the end of November 1937, the following oil-producing methods were in use: 395 wells flowing, 491 pumping, 97 on air-gas lift and 252 wells miscellaneous. There were no flooding operations. The oil is produced from the Miocene and Eocene and is of both asphalt and paraffin base. The gas produced averaged approximately 1050 B.t.u. per cu. ft. with 0.8 gal. of gasoline per 1000 cubic feet.

Jan 1, 1938

By AIME AIME

THE Fall Meetings of the Institute of Metals Division and of the Iron and Steel Division were held in Cleveland from Tuesday, Oct. 20, to Thursday, Oct. 22, as a part of the National Metal Congress. The registration at the technical sessions was something over 450 and the attendance at the joint dinner of the two Divisions on Wednesday evening taxed the capacity of the dining room. The president of the British Institute of Metals, W. R. Barclay, consulting metallurgist to the Mond Nickel Co., Ltd.; of London, was in attendance at several of the technical sessions and was one of the after-dinner speakers at the banquet. He commented on the desirability of greater international amity and cooperation in these troubled times and of the role that technical societies, such as the A. I. M. E. and his own British Institute of Metals, can and indeed are playing in bringing this to pass, with their membership and contacts reaching to all parts of the world. He also referred to the new reciprocal membership arrangements in effect between the A.I.M.E. and the British Institute of Metals.

Jan 1, 1936

By J. B. Austin

IN developing a consistent picture of the thermal expansion of the commercial chromium steels, which cover a range of carbon contents, it is desirable to know the expansion in the limiting case of the binary, carbon-free, iron-chromium alloys. We have, therefore, determined the thermal expansion of a series of five special alloys, ranging in chromium content from 3 to 10.5 per cent, with not more than 0.03 per cent carbon, over a temperature range extending beyond the transformation region; this low carbon content enables us to draw reasonably reliable conclusions as to the behavior of the carbon-free system. Moreover, the measure-ments serve to determine the beginning and the end of the alpha-gamma transformation; and they emphasize once more the fact that a transforma-tion temperature determined by any method in which the specimen is cooled at an appreciable rate is apt to be seriously in error, particularly if the metal contains a transformation-retarding element such as chro-mium or managanese. The lag, or undercooling, observed at the ? - a transformation is explained in terms of the influence of temperature on transformation velocity; the rather unusual shape of the ? loop is attributed to a change with temperature and with composition of the distribution of chromium between the alpha-iron and gamma-iron solid solutions. The exact composition of the alloys which were obtained through the courtesy of Dr. W. Rohn, of the Heraeus Vakuumschmelze A-G., is given in Table 1. Determinations of the linear thermal expansion and of transformation temperature were carried out in the vacuum dila-tometer previously described,1 using a rate of heating and of cooling of 3.0° to 3.5° per minute unless otherwise stated. Magnetic susceptibility, which was measured in studying the rate of transformation, was determined with a magnetic balance, which also has been described.2

Jan 1, 1935

By L. W. Holm

Laboratory flooding experiments on linear flow systerns indicated that high oil displacement, approaching that obtained from completely miscible solvents, can be attained by injecting a small slug of carbon dioxide into a reservoir and driving it with plain or carbonated water. Data are presented in this paper which show the results of laboratory work designed to evaluate this oil recovery process, particularly at reservoir temperatures above 100°F and in the pressure range of 600 to 2,600 psi. Under these conditions CO2 exists as a dense single-phase fluid. It was found that a bank, rich in light hydrocarbons, was formed at the leading edge of the CO? slug during floods on long cores. Formation of this bank is probably due to a selective extraction by the C02 and, it is believed, partially accounts for the attractively high oil recoveries. In crddition to the efficient displacernerlt of oil from the pores of the rock by this process, the favorable rnobility ratio related to a C0 2-water flood also contributes to high oil recovery. A further advantage of this process is noted on limestone and dolomite rock, in that the CO1 reacts with the porous medium increasing its permeability. Flooding experiments were conducted on sandstone and vugular dolomite models. The results of this experimental work show the effect on oil recovery of type of porous medium, pore geometry, flooding length, and flooding pressure. The porosity of the cores and rilodels varied from 16 to 21 per cent and their pern~eabilities ranged from 100 to 200 md. A reconstituted West Texas reservoir oil, a West Texas stock tank oil, an East Texas stock tank oil and Soltrol were used to represent reservoir oils in this study. Oil recoveries ranging from 60 to 80 per cent of the original oil in place in these cores were obtained by CO2,-carbonated water floods at pressures between 900 and 1,800 psi, compared with conventional solution gas drive and water-flood recoveries of 30 to 45 per cent on the same cores. Oil recoveries greater than 80 per cent resulted frorn f1oods at pressures above about 1.800 psi. There high recoveries were noted from both the sandstone and the irregular Porosity carbonate cores. In all floods, additional oil was recovered by a solutiorr gas drive resulting from blowdown following the flood. Oil recoveries of 6 to 15 per cent of the original oil in place were obtained during this blowdown period. This additional recovery was found to be a function of oil remaining after the flood, decreasing with decreasing oil saturation. It was also noted that highest oil recoveries by blowdown were obtained when carborlated water rather than plain water followed the CO, slug. INTRODUCTION Miscible phase or solvent flooding processes, which are designed to increase oil recovery -from petroleum reservoirs, involve the injection of small quantities of a petroleum solvent into the reservoir, followed by an inexpensive scavenging fluid which is miscible with the solvent. Essentially complete displacement of oil from the pores of reservoir rock has been obtained by this technique. CO,, although not completely miscible with most reservoir oils at moderate pressures, is highly soluble in these oils at pressures above about 700 psi; there is appreciable swelling and reduction in the viscosity of oil when CO, is dissolved in it. Therefore, CO, could be expected to perform similarly to other oil solvents as a displacing agent. CO, is also highly soluble in water at elevated pressures, so water should be a satisfactory material to drive a slug of CO, through an oil-bearing reservoir. A favorable mobility ratio would be obtained through the reduction in viscosity of the oil and the use of water as a final displacing agent. A number of investigations of the use of CO, to improve oil recovery have been reported in the literature.2,3,4,5,6 These studies, however, have been conducted on uniform porosity sandstone at relatively low temperatures and pressures. The behavior of CO1 as a flooding agent at temperatures above its critical temperature could not be predicted adequately from these studies, particularly for the case of non-homogeneous rock. The purpose of this work was to evaluate the oil recovery efficiency of a process involving the injection of a CO2 slug followed by carbonated water, at reservoir temperatures above 100°F and in the pressure range of 600 to 2,600 psi, and to compare this process with conventional water flooding. The investigations were primarily designed to provide information on the efficiency of the process in irregular porosity carbonate rock. The effects of flooding path length, the presence of free gas, the type of oil to be recovered, and the amount of solvent required were also determined. The essential results of static phase behavior studies and experimen-

By W. A. West

One who attempts to collect and classify equilibrium data from various iron-alloy systems is soon struck with the absence of any quantitative theory that can serve as a general background against which to compare and contrast results from different systems, at different temperatures, and with different concentrations. It is not necessary to wait for a perfect theory; investigation of divergences of theory from observation may prove of great value in acquiring understanding of the subject. For example, one has only to think of Raoult&apos;s law as applied to aqueous solutions. The equations developed by Zener1 represent an effort to provide such a quantitative theoretical background, and it is therefore desirable to subject this theory to such tests as can be applied. The present article is intended to be an application of available tests, and may thus be considered as a supplement to Zener&apos;s paper. It is assumed that this paper is available to the reader. The equations make it possible to calculate the effect on the equilibrium concentration of one alloying element due to the presence of one or more other elements. In particular. they are intended to give, for alloy steels, the carbon concentrations in alpha and gamma phases in equilibrium with each other, and in gamma in equilibrium with cementite. They may, however, be modified for use for carbon-free alloys. A summary is given later of the equations used in analyzing the data in this paper, and the symbols are there defined. About 125 papers have been examined for experimental data suitable for this investigation. An effort was made to look up all available reports of ternary systems including iron and carbon, as well as similar systems of higher order. Supplementary material was also obtained from a number of binary systems. A few noncarbon ternary systems were also found to which these methods could be applied. A comparatively small proportion oi the papers read provided usable material. In many systems the number of quantitative observations made in the iron-rich region is extremely small, and the smoothed curves to be found in most published phase diagrams are entirely useless for quantitative treatment. This opinion is confirmed by the authors of the series on Alloys of Iron Research, whose remarks show clearly that they have no illusions as to the accuracy of many diagrams that they present. A further difficulty arises from the fact that these equations apply only to rather low percentages of alloying elements. The result is that at the lowest concentrations, where the best agreement might be hoped for, the errors of observation become relatively very large. The experimental difficulties in measurements of this kind of equilibrium are, of course, an old story.

Jan 1, 1947

By W. A. West

One who attempts to collect and classify equilibrium data from various iron-alloy systems is soon struck with the absence of any quantitative theory that can serve as a general background against which to compare and contrast results from different systems, at different temperatures, and with different concentrations. It is not necessary to wait for a perfect theory; investigation of divergences of theory from observation may prove of great value in acquiring understanding of the subject. For example, one has only to think of Raoult&apos;s law as applied to aqueous solutions. The equations developed by Zener1 represent an effort to provide such a quantitative theoretical background, and it is therefore desirable to subject this theory to such tests as can be applied. The present article is intended to be an application of available tests, and may thus be considered as a supplement to Zener&apos;s paper. It is assumed that this paper is available to the reader. The equations make it possible to calculate the effect on the equilibrium concentration of one alloying element due to the presence of one or more other elements. In particular. they are intended to give, for alloy steels, the carbon concentrations in alpha and gamma phases in equilibrium with each other, and in gamma in equilibrium with cementite. They may, however, be modified for use for carbon-free alloys. A summary is given later of the equations used in analyzing the data in this paper, and the symbols are there defined. About 125 papers have been examined for experimental data suitable for this investigation. An effort was made to look up all available reports of ternary systems including iron and carbon, as well as similar systems of higher order. Supplementary material was also obtained from a number of binary systems. A few noncarbon ternary systems were also found to which these methods could be applied. A comparatively small proportion oi the papers read provided usable material. In many systems the number of quantitative observations made in the iron-rich region is extremely small, and the smoothed curves to be found in most published phase diagrams are entirely useless for quantitative treatment. This opinion is confirmed by the authors of the series on Alloys of Iron Research, whose remarks show clearly that they have no illusions as to the accuracy of many diagrams that they present. A further difficulty arises from the fact that these equations apply only to rather low percentages of alloying elements. The result is that at the lowest concentrations, where the best agreement might be hoped for, the errors of observation become relatively very large. The experimental difficulties in measurements of this kind of equilibrium are, of course, an old story.

Jan 1, 1947

By W. C. Ellis

IN an ingot of germanium solidified progressively from the bottom by a method&apos; devised by J. H. Scaff and H. C. Theuerer, examination discloses ex- IH. C. Torrey and C. A. Whitmer, Crystal Rectifiers. p. 364. 1948. New York. McGraw-Hill Pub. Co. tensive twin relationships. A slice taken about midway in a cylindrical ingot approximately 3/4 in. in diameter and 1 1/2 in. in length, after etching and polishing to delineate different orientations, is shown in fig. la. The orientations of the regions designated with letters were determined by Laue X-ray back-reflection methods and plotted on stereograms. The orientation relationships of the designated components were determined by comparing the values for the nine angles between the three respective cube poles of each orientation with the values calculated in a formal treatment of octahedral multiple twinning in cubic crystals. Germanium, diamond cubic in structure, has the octahedral twinning habit. I am indebted to K. H. Storks for the calculation of the angular relationships of cube poles in octahedral twinning to four orders. The set of values for the nine angles is distinctive of the order of twinning. Confirmation for a multiple twin relationship is obtained from the determined indices of the mirror planes. These exist for all orders of twinning through the third and for some of the fourth." If the orientations are not those for twinning, then the nine angles for the cube poles do not correspond in value and distribution to those formally calculated. Since all nine angles must correspond in values and distribution of values to the calculated ones, the Laue method with a precision of one or two degrees is adequate to establish or deny with confidence the existence of multiple twins. Regions of the same orientation can also frequently be identified by the optical reflections. For example, the narrow twin bands in A at 2: 00 o&apos;clock have orientation B1. The interesting twin relationships shown schematically in fig. lb were found for the section in fig. la. Most of this slice was made up of orientation, A, appearing in widely separated regions. Of the four possible first order twins of A, three were present in this slice and are designated by B with subscripts. Four second order twins of A are designated by C with subscripts. It is worth emphasizing that two of these, C, and C,, are second orders of A through the first order missing in this section. Two regions, designated by D with subscripts are third order twins of A. D2 is a sixth order twin of D,. All orientations found were ascribable to multiple twinning, as if the orientations in this section originated earlier in solidification from a single nucleus. The presence of extensive multiple twinning to- gether with the absence of other orientations appears to be a characteristic result in many instances of solidification of germanium. Fertile conditions for twinning probably exist in the array of atoms in the diamond cubic structure. The high order twins in the section shown, it is reasonable to presume, are the result of progressive octahedral twinning through several generations in the material freezing earlier. Some of these generations do not appear in this section, it is suggested, because their orientations with respect to the growth direction were unfavorable for survival. The extensive twinning is probably promoted during solidification by constraint imposed by volume increase, and to an irregular growth front. Twinning may also be due, in part, to the attempt of the solidifying region to attain the orientation most favorable to the growth direction (maximum thermal gradient). The nucleus for a twinned orientation could have its origin in a "stacking fault" on the close-packed octahedral plane. Further work is being done in which the course of twinning throughout an ingot is being studied. The results appear to be important in the general theory of solidification.

Jan 1, 1951

By William E. Ford, Edward Salisbury Dana

1. Normal Class (6) Zircon Type 2. Hemimorphic Class (7) Iodusuccinimide Type 3. Pyramidal Class (8) Scheelite Type 4. Pyramidal- Hemimorphic Class (9) Wulfenite Type 5. Sphenoidal Class (10) Chalcopyrite Type 6. Trapezohedral Class (11) Nickel Sulphate Type 7. Tetartohedral Class (12) Mathematical Relations to the Tetragonal System THE TETRAGONAL SYSTEM includes all the forms which are referred to three axes at right angles to each other of which the two horizontal axes are equal to each other in length and interchangeable and the third, the vertical axis, is either shorter or longer. The horizontal axes are designated by the letter a; the vertical axis by c (see Fig. 166). The length of the vertical axis expresses properly the axial ratio of a : c, a being uniformly taken as equal to unity. The axes are orientated and their opposite ends designated by plus and minus signs exactly as in the case of the Isometric System. Seven classes are embraced in this system. Of these the normal class is common and important among minerals; two others have several representatives, and another a single one only. It may be noted that in four of the classes the vertical axis is an axis of tetragonal symmetry; in the remaining three it is an axis of binary symmetry only.

Jan 1, 1922

By John W. Cloud

In 1877 the Pennsylvania Railroad Company removed an old bridge from its line at Duncannon, Pa., built intermediate piers and erected shorter spans of the Pratt truss type, which had previously been in use on another portion of the road. The design of this truss would not admit of diagonals larger than 19 inches diameter, and in order to stiffen the bridge somewhat steel rods were introduced for the main diagonals in the first and second panels, 19 inches and 18/8 inches diameter respectively. These rods were threaded without upsetting, and by the ordinary formulae the strains were of the same intensity upon both, viz., 16,000 pounds per square inch with the maximum loading. The other main diagonals in the truss are 19 inches diameter, and of iron. It was specified for the steel rods: Elastic limit,.......46,000 Ibs. Tensile strength,. .. ,. .. 80,000 lbs. Elongation,,.,.,. 20 per cent. The steel was procured without difficulty, and it allowed a factor of safety of 23/4 at elastic limit, while a similar factor of 2½ had for a long time been successfully used for iron. In the course of three years, from time to time, six of these steel rods broke, three of them being 18 inches in diameter, and three 19 inches in diameter. The broken rods were tested, and three of them analyzed at Altoona to ascertain the cause of failure, and what modifications should be made in the steel for such service. Examination showed that all the rods were broken in detail close under the nut. The threads were well cut and properly rounded at the root. testing the rods micrometer screws, reading to .0001" with c bell to signal the contact, were attached to the test pieces, and by this means the modulus of elasticity and elastic limit accurately obtained.

Jan 1, 1881

September 1 to 6, 1918 COMMITTEE IN CHARGE Spencer Penrose, Chairman. George M. Taylor, Vice-Chairman. A. E. Carlton, Chairman. Finance Committee J. Dawson Hawkins, Secretary DENVER COLORADO SPRINGS CRIPPLE CREEK Finance Finance Thomas B. Crowe T. B. Stearns A. E. Canton , E. P. Arthur, Jr. Richard A. Parker Spencer Penrose N. S. Greensfelder T. B. Burbridge George M. Taylor A. E. Carlton. A. L. Blomfield, Treasurer B. F. Hill Arrangement I F. G. Willis Dave G. Miller Registration Norris E. Eads Frank Bulkley Loren C. Lennox 1V. E. Ryan Geo. E. Collins Horace F. Lunt Fred Jones .1. M. Tippett F. D. Smale Entertainment J. H. Haynes F. H. Bostwick Arrangement and Entertainment L. W. Lennox F. E. Shepard George M. Taylor A. L. Blomfield M. R.. Valentine Howland Bancroft J. D. Hawkins Thomas B. Crowe B. P. Morse A. E. Carlton E. P. Arthur J. G. Perry G. H. Clevenger Etienne A. Ritter Ladies Ladies , PUEBLO Mrs. T. B. Stearns, Mrs. C. M. Taylor, Mrs. C. H. Clevenger J. F. Welborn Chairman. Chairman H. B. Carpenter Mrs. C. Loughridge Mrs. S.-Penrose Mrs. A. E. Carlton L. B. Eames Mrs. H. Bancroft Mrs. J. D. Hawkins Mrs. A. L. Blomfield F. Robinson Mrs. G. Bancroft Mrs. L. C. Lennox Mrs. J. M. Tippett . Mrs. W. D. Leonard Mrs. H. F. Lunt -Mrs. E. C. van Diest Mrs. C. Chase Mrs. E. A. Ritter Mrs. AV. Strieby Mrs. F. H. Bostwick Mrs. L. S. Harner Mrs. C. L. Bailey Mrs. F. Bulkley Miss F. Dickerman Mrs. E. P. Shove Mrs. C. L. Tutt Mrs. F. C. Peck Mrs. F. D. Pastorius

Jan 10, 1918

By Oliver Bowles

THE most important non-metallic mineral industries from a tonnage standpoint are those that are allied with the construction industries and are engaged in handling sand and gravel, crushed stone, building stone, cement, lime and gypsum. The greatest problem facing a number of these industries at this time is over-production. They have experienced un- usual, and in some instances phenomenal, growth during recent years, stinlulated by extensive highway and building construction, but in some localities expansion of producing plants has far outstripped industrial needs. The cement industry is operating at about two- thirds capacity. Over-production tends toward price- cutting and unprofitable and interrupted operation, involving maintenance expenses for idle plants and disorganization of working forces. This condition has encouraged active efforts toward reducing production costs by the introduction of labor-saving equipment. Also, there is a tendency toward the location of manufacturing plants, wherever possible, near the centers of consumption rather than at points of production of raw materials. In order to reduce overhead expense, or for other reasons, many consolidations of companies into larger units have taken place. An economic study of conditions in these industries is highly desirable. The U. S. Bureau of Mines has taken one step forward in this direction in the issuance of Economic Paper 7, entitled "Economics of New Sand and Gravel Developments." Briefly, this report emphasizes the importance of making a thorough study of all the economic factors involved before undertaking new .enterprises.

Jan 1, 1930

By J. V. Calara, J. D. Miller

The sign of the surface potential for complex non-reactive ionic solids cannot be predicted solely from consideration of the hydration energy of gaseous ions which constitute the ionic lattice. Accurate analysis of these systems must involve the hydration energy of surface ions, which requires knowledge of the crystal structure, the identification of cleavage planes, and the calculation of binding energies of surface ions. Surface binding energies for ionic solids can be determined if the Surface Madelung Constant is known. A computational technique was developed for the calculation of Madelung Constants for infinite lattices which gives excellent agreement with the values calculated by other more complicated methods reported in the literature. Extension of this technique permits the calculation of Surface Madelung Constants and binding energies of surface ions, [Aus], for semi-infinite solids. The hydration free energy of gaseous ions, [AFh], together with the calculated binding energy of surface ions, [Aus], allows calculation of the hydration energy of surface ions,[AGh], as for the case of the ionic solid, MX: [ ]

Jan 1, 1976

I. PRESIDING OFFICERS. At all Business meetings of the Institute the President, or, in his absence, the Vice-President, or, in the absence of both of them, any other member of the Board of Directors to be chosen by the meeting, shall preside. At all other meetings of the Institute the President of the Council or, in his absence, one of the Vice-Presidents, if present, shall preside II. ORDER OF BUSINESS. At each Business meeting of the Institute the order of business shall be as follows 1. Reading of minutes of preceding meeting. 2 Report of the President. 3. Report of the Treasurer. 4. Report of the Secretary. 5. Election of Directors. 6. Election of Members of the Council. 7. Reports of Standing Committees. 8. Reports of Special Committees. 9. Special Orders 10. Miscellaneous business. This order of business may be changed by a vote of a majority of the Members and Associates present in person or by proxy. The usual parliamentary rules shall govern all meetings of the Institute except in cases otherwise provided by the Constitution or the By-Laws. At all sessions of the Institute other than business meetings, the order of proceedings and the time of adjournment, shall rest in the discretion of the presiding officer

Jan 1, 1917

I. PRESIDING OFFICERS. At all Business meetings of the Institute the President, or, in his absence, the Vice-President, or, in the absence of both of them, any other member of the Board of Directors to be chosen by the meeting, shall preside. At all other meetings of the Institute the President of the Council or, in his absence, one of the Vice-Presidents, if present, shall preside II. ORDER OF BUSINESS. At each Business meeting of the Institute the order of business shall be as follows 1. Reading of minutes of preceding meeting. 2 Report of the President. 3. Report of the Treasurer. 4. Report of the Secretary. 5. Election of Directors. 6. Election of Members of the Council. 7. Reports of Standing Committees. 8. Reports of Special Committees. 9. Special Orders 10. Miscellaneous business. This order of business may be changed by a vote of a majority of the Members and Associates present in person or by proxy. The usual parliamentary rules shall govern all meetings of the Institute except in cases otherwise provided by the Constitution or the By-Laws. At all sessions of the Institute other than business meetings, the order of proceedings and the time of adjournment, shall rest in the discretion of the presiding officer

Jan 1, 1923

I PRESIDING OFFICER At all business meetings of the Institute the President, or, in his absence, the First Vice-President, or, in the absence of both of them, any other Vice¬ President or Director, chosen by the meeting, shall preside At all other meetings of the Institute the President, or, in his absence, one of the Vice-presidents shall preside If none of these be present the meeting shall elect a Chairman The President shall do and perform such other duties as may from time to time be assigned to him by resolution of the Board of Directors of the Institute II ORDER OF BUSINESS At each business meeting of the Institute the order of business shall be as follows 1 Reading of minutes of preceding meeting 2 Report of the President 3 Report of the Treasurer 4 Report of the Secretary 5 Election of Directors 6 Reports of Standing Committees 7 Reports of Special Committees 8 Special Orders 9 Miscellaneous business This order of business may be changed at any meeting, by a vote of a majority of the Members and Associates present At all sessions of the Institute, other than business meetings, the order of proceedings and the time of adjournment shall rest in the discretion of the presiding officer

Jan 1, 1923

By W. H. Emmons

This paper is the third of a series treating of the relations of ores of the metals to igneous rocks. The first&apos; outlined the general problem; the second2 proposed a classification of lode ores, and showed how the distribution of the deposits is in a certain measure controlled by the contour of the roof of the parent batholith. A number of mining districts were discussed, the examples being selected chiefly from group 2 of the classification. The proposed classification of lode deposits, briefly stated, is as follows: 1. Cryptobatholithic: near hidden batholiths which have not yet been exhumed by erosion. 2. Acrobatholithic: in and near cupolas or domes of batholiths—the high points of larger underlying masses. 3. Epibatholithic: on batholiths, near their rims, but below eroded cupolas, or below the highest points of the roofs. 4. Embatholithic: among closely-spaced outcrops which probably are parts of a single bathohth. The outcrops of invaded rocks predominate. 5. Endobatholithic. in and near roof pendants of large batholiths. The invading rocks predominate. 6. Hypobatholithic: in deeply-eroded batholiths, where even roof pendants have been eroded. Deposits of certain metals on the roofs of the batholiths are much more numerous in some positions than deposits of other metals, and the horizontal zonal arrangements of lodes of different metals are shown characteristically only in certain groups. In a large measure, also, the character of the fracturing and metallization is determined by the position on the roof of the batholith. The disseminated copper ores in porphyry constitute a clearly-defined type. All the deposits of these ores, as far as known, are in group 2. They appear to have been formed only in and around small upward projections of the parent granitic masses, and not low on the walls of the

Jan 1, 1927