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By G. J. Roe

Drawing largely on desulfurizing practices which have been developing abroad in the last several years, this paper will cover the main ways in which producing steels with low sulfur provides appreciable benefits -- beginning with improvements in ingot processing and carrying over into improved product properties, in particular cleanliness, formability, notch toughness and weldahility. Because the raw materials and fuels used in steelmaking are sources of sulfur and the removal of this element is difficult, sulfur has tended to be accepted as an unavoidable incidental contaminant of steel. Although it was early recognized that sulfur significantly affects several mechanical properties, the main concern was with its effect on hot shortness. Concentrating on countering this effect, operators have traditionally added manganese in sufficient multiples of the sulfur content to form manganese sulfide and thus avoid iron sulfide formation, the assumption being that the steel would then be acceptable in terms of both processing and mechanical properties.

Jan 1, 1972

By Rex T. Ellington

The fluidized bed is an effective method for investigating retorting phenomena and possibly a commercial means of retorting oil shale. Both were examined by Sinclair Oil (now part of Atlantic Richfield Co.) in the period 1965-1698. The results of the work show that the presence of an oxidizing environment during retorting results in loss of oil yield which indicates that vapor phase oil burns in preference to combustion of coke on spent shale. Consideration of hardware indicates that there are several possibilities for commercial embodiment. As a companion to shaft-type retorts the fluidized bed could have good potential. Realistic assessment of costs suggests that further development may have to wait commercialization of another process.

Jan 1, 1974

By M. E. Wadsworth, A. E. Lewis, R. L. Braun

Experimental results obtained in laboratory leaching studies of primary copper sulfide ore in sulfuric acid systems pressurized with oxygen are interpreted by a computerized geometric model involving the movement of a reaction zone through the ore fragments. Physical properties of the ore, including size, shape, and mineral content, are considered. The leaching mechanism involves mixed kinetics and includes a surface reaction within a moving reaction zone plus pore diffusion of dissolved oxygen through the reacted portion of the ore fragment to the reaction zone. The results are applicable to conditions that would exist in nuclear solution mining or similar processes in which the ore is converted into rubble and then inundated by a leach solution adequately supplied with oxidants. Experimental results at 90°C are correlated with the model, which includes temperature-dependent parameters.

Jan 1, 1974

By James P. Kimball

BY the term weathering of coal is meant the process of deterioration to which under various circumstances it may be exposed at ordinary temperatures, both from outward agencies on the one hand, and on the other hand from its own constitutional qualities. This process involves along with some minor qualitative changes certain quantitative changes resulting in a gradual and limited reduction in the quantity of the organic elements, and relatively a corresponding increase of its inorganic or mineral constituents as represented by its ashes, and often in an increase of the absolute weight of the coal. In common with many mineral substances, coal absorbs oxygen

Jan 1, 1880

By James P. Kimball

By the term weathering of coal is meant the process of deterioration to which under various circi~mstances it may be exposed at ordinary temperatures, both from outward agencies on the one hand, and on the other hand from its own constitutional qualities. This process involves along with some minor qualitative changes certain quantitative changes resulting in a gradual and limited reduction in the quantity of the organic elements, and relatively a corresponding increase of its inorganic or mineral constituents as represented by its ashes, and often in an increase of the absolute weight of the coal. In common with many mineral substances, coal absorbs oxygen

Jan 1, 1880

By H. H. Kaveler

A summary of the reservoir engineering and related geologic data on the Schuler field, Union County, Arkansas, is presented here in a manner intended to interest both technical and nontechnical readers. The Cotton Valley formation and the Reynolds oolite are oil-productive formations in the Schuler field, but the Jones sand pool, at a depth of 7500 ft., developed with 146 wells on zo-acre spacing, is the reservoir of principal interest. The Jones sand sandstone reservoir is an anticlinal trap typically gas-drive or depletion type in performance. The core analyses from 88 per cent of the wells drilled, together with drilling time and electric-log data, yield an accurate estimate of the "productive" sand thickness and its areal distribution over the pool. Accurate production statistics, monthly reservoir-pressure surveys, and bottom-hole sample analyses when correlated by the "material-balance equation" show unusually good agreement with that principle. Estimates of oil initially in place made by the material-balance method and the sand-volume method are in good agreement at 116 to rzo million barrels. The reservoir-pressure history of the pool reflects the reaction of a reservoir to production, proration and secondary-recovery practices. The cost of the extensive program of reservoir study in the Jones sand pool has been estimated, in order to emphasize the value derived from such an investment through better understanding of a reservoir's reaction to production practices. Unit operation of 140 of the 146 Jones sand wells made possible an effective unitized gas-injection pressure-maintenance program. Res-ervoir-pressure decline was arrested, natural flow was maintained, and pumping and lease equipment were conserved. An increased ultimate recovery of zo million barrels beyond the estimated 34 million barrels primary recovery is indicated at present. Extension of the Jones sand unit to include the undeveloped Cotton Valley formation will permit additional recovery of otherwise uneconomic reserves of oil through wells no longer required in the Jones sand operations. Introduction The Schuler field comprises approximately 4000 acres in and about sec. 18, T. 18 S., R. 17 W. in west central Union County, Arkansas. Three reservoirs are procluctive of oil and gas: the Cotton Valley formation, the Jones sand, and the Reynolds oolite section of the Smackover limestone. The Jones sand pool is the most important reservoir from an engineering viewpoint. It possesses the traditional and somewhat classic characteristics usually associated with an anticlinal trap. Development and operations have followed the dictates of advanced engineering practices. The pool has attracted attention because of the unusually detailed reservoir data obtained, its interesting production history, and the success of the unitized gas-injection pres-sure-maintenance operation now being carried out. The purpose of this paper is to present a summary of the engineering data relating to the field, with particular reference to the more interesting general applications of

Jan 1, 1944

By H. H. Kaveler

A summary of the reservoir engineering and related geologic data on the Schuler field, Union County, Arkansas, is presented here in a manner intended to interest both technical and nontechnical readers. The Cotton Valley formation and the Reynolds oolite are oil-productive formations in the Schuler field, but the Jones sand pool, at a depth of 7500 ft., developed with 146 wells on zo-acre spacing, is the reservoir of principal interest. The Jones sand sandstone reservoir is an anticlinal trap typically gas-drive or depletion type in performance. The core analyses from 88 per cent of the wells drilled, together with drilling time and electric-log data, yield an accurate estimate of the "productive" sand thickness and its areal distribution over the pool. Accurate production statistics, monthly reservoir-pressure surveys, and bottom-hole sample analyses when correlated by the "material-balance equation" show unusually good agreement with that principle. Estimates of oil initially in place made by the material-balance method and the sand-volume method are in good agreement at 116 to rzo million barrels. The reservoir-pressure history of the pool reflects the reaction of a reservoir to production, proration and secondary-recovery practices. The cost of the extensive program of reservoir study in the Jones sand pool has been estimated, in order to emphasize the value derived from such an investment through better understanding of a reservoir's reaction to production practices. Unit operation of 140 of the 146 Jones sand wells made possible an effective unitized gas-injection pressure-maintenance program. Res-ervoir-pressure decline was arrested, natural flow was maintained, and pumping and lease equipment were conserved. An increased ultimate recovery of zo million barrels beyond the estimated 34 million barrels primary recovery is indicated at present. Extension of the Jones sand unit to include the undeveloped Cotton Valley formation will permit additional recovery of otherwise uneconomic reserves of oil through wells no longer required in the Jones sand operations. Introduction The Schuler field comprises approximately 4000 acres in and about sec. 18, T. 18 S., R. 17 W. in west central Union County, Arkansas. Three reservoirs are procluctive of oil and gas: the Cotton Valley formation, the Jones sand, and the Reynolds oolite section of the Smackover limestone. The Jones sand pool is the most important reservoir from an engineering viewpoint. It possesses the traditional and somewhat classic characteristics usually associated with an anticlinal trap. Development and operations have followed the dictates of advanced engineering practices. The pool has attracted attention because of the unusually detailed reservoir data obtained, its interesting production history, and the success of the unitized gas-injection pres-sure-maintenance operation now being carried out. The purpose of this paper is to present a summary of the engineering data relating to the field, with particular reference to the more interesting general applications of

Jan 1, 1944

By W. R. Hibbard, J. D. Nisbet

The high temperature properties of Fe-Cr-Co-Ni base alloys and the effects of hardening element additions on these properties are rationalized on the basis of general principles of alloying. DURING the past few years the base elements in high temperature austenitic alloys have gradually been changed from iron-rich materials to nickel-rich, then to cobalt-rich and more recently to various iron, cobalt, and nickel combinations, all with an approximately constant chromium content of 20 pct. Concurrently, the hardening additions of the incongruous* elements, have been shifted from small amounts of a single element to various ratios of molybdenum, tungsten, columbium, carbon, titanium, and aluminum with the percentages of these constituents continually increasing. It has been known that the typical soft high temperature alloy (such as Inconel) consisted of face-centered cubic austenite, but the effect of varying the composition of the base elements, iron, chromium, nickel, and cobalt, has not been broadly analyzed. Therefore, it was reasoned that the first major problem in the understanding of the properties or the further development of high temperature alloys was to study systematically the effect of composition upon the mechanical properties of face-centered cubic Fe-Ni-Co-Cr austenitic solid solutions. The matrix of the strong high temperature alloys (such as Inconel X) is usually also a face-centered cubic solid solution of iron, nickel, chromium, and cobalt but with additional phases which can be generally classified as intermetallic compounds and carbides. It is usually observed that combinations of the hardening elements, tungsten, molybdenum, columbium, tantalum, titanium, aluminum, carbon, and others have been used in these strong high temperature alloys. Thus, it was reasoned that a second major problem in studying these alloys was to understand the effect on mechanical properties of adding

Jan 1, 1954

By A. L. Holley

THE application of scientific methods to the investigation of natural laws and to the conduct of the useful arts which are founded upon them, is year by year mitigating the asperity and enlarging the outcome of human endeavor. More notably, perhaps, are these the facts in that system of productive and constructive arts of, which engineering is the general name. In metallurgical engineering especially, within the period of our own recollection, how rapid has been the rate and how wide the scope of progress: the scientific discovery and mining of metalliferous veins; the economical separation and reduction of ores of every grade; the production and regulation of high temperatures; the varied improvements in the manufacture of iron, in saved heat and work, in uniformity and range of products ; and, most important of all, the creation and the utilization, to be counted by the million tons a year, of the cheap constructive steels. Wonderful as this range and degree of development may appear to the public eye, the close and thoughtful observer must, nevertheless, conclude that neither the profession nor the craft of engineering may congratulate themselves too complaisantly, but that they should rather acknowledge to each other the embarrassing incompleteness of the union between engineering science and art. There is a small school of philosophers whom we may designate as original investigators, men who come close to nature, who search into first principles, and who follow that scientific and therefore fruitful method by which the relations of matter and force are discovered, classified, and brought within the reach of practice. These wonderful - men do not indeed create the laws of nature, as they sometimes almost seem to, but they go up into the trembling mountain and the thick darkness and bring down the tables upon which they are written. * President's Opening Address. The discussion following this paper, and also the Joint Discussion of the Institute and the American Society of Civil Engineers, on the subject of Technical Education., are published in a separate volume.

Jan 1, 1876

By Eugene Stebinger

PAGE Introduction.............. 890 Position oF Montana in the Western Coal Province*..... 890 Montana's Total Coal Tonnage.........891 THe Coal-BearINg Formations,........891 General Statement............. 891 Kootenai Formation............ 895 Eagle Sandstone............896 Judith River Formation............ 896 Homethief or Lennep Sandstone.........897 Lance Formation..........• 897 Fort Union Formation............ 898 Tertiary Lake Beds............. 899 Distribution of the Coal Fields.......... 899 Classification of Montana Coals.........900 General Statement............. 900 Comparison of Chemical Analyses and Heating Values..901 DESCriPTions of the CoaL Fields.......... 905 • Fields Containing Bituminous and Higher Grade Coals..905 Bridger Field............. 905 Stillwater Field............ 906 Electric Field............ 907 Trail Creek Field...........908 Gallatin Field............909 Lombard Field...........910 Great Falls Field............ 910 Lewistown Field............ 911 Valier Field............. 912 Blackfoot Field............ 913 Fields Containing Sub-bituminous Coal.. 913 Bull Mountain Field..........913 Red Lodge Field............ 914 Missoula and Drummond Fields......... 916 Milk River Field............ 916 The Eastern Plains Region of Lignite and Sub-bituminous Coal.... 917

Jan 1, 1914

By C. W. Vaupell

THE Huitzuco mines lie in north central Guerrero, Mexico; production has been about 90,000 flasks of quicksilver since 1873. Near-surface ores fill extinct mud geysers and the deep deposits are chambered veins, stock-works in brecciated blocks, and replacements in limestone. The epigenetic minerals livingstonite, stibnite and sulphur occur in limestone, gypsum and dolomite through a developed vertical range of 260 meters. The deepest workings expose an increased amount of stibnite, which probably indicates that the lower limit of mercury mineralization is being approached. A resurgence of heat and water formed geysers over an extended area after the period of mercury mineralization. Mud geysers, which are situated, in the outcrops, contain the secondary mercury minerals, cinnabar and barcenite in the gravel and mud filling the vents. A 150-ton flotation plant is in operation concentrating stope fills that assay 3.0 kg. of mercury per ton. In one open stope, which is more than one hectare in area and 60 m. high, 150,000 tons are available. INTRODUCTION The Huitzuco mercury mines are of interest because of the unusual occurrence of ore in extinct geyser vents and the presence of several rare mercury minerals. Some of the deposits have typical characteristics of the telethermal zone and there is a gradation towards typical epithermal mineralization in depth. Halse,1 Villarello,2 Mactear3 and Merrill4 have described the geology and the early operations in the district, and Barcena5 and Mallet6 have described the rare mercury minerals, livingstonite and barcenite, found at Huitzuco. LOCATION The village of Huitzuco lies in the north central part of the State of Guerrero, Mexico, 27 km. (16.7 miles) east of Iguala, which is the largest and most important town in the area. Iguala is served by the Mexican National Railways and also by the Mexico City-Acapulco highway. The highway is surfaced from Mexico City to Iguala, a distance of 200 km. (124 miles) by road, and there is a fairly good, level, dirt road from Iguala to Huitzuco. The elevation above sea level is about 1000 m. (3280 ft.). The climate is warm and very dry except during the rainy season, from June to

Jan 1, 1937

By E. A. Kaarsberg

The electron photomicrographs shown in this paper are of samples of the A.P.I. Reference Clay Minerals Montmorillonite No. 27 and Kaolinite No. 4 and of a shale from Spraberry Oilfield in Texas. These samples are part of a larger collection whose physical properties, composition and internal structure were previously studied by ultra-sonic and X-ray methods. ' Elastic anistropy was indicated in the montmorillonite and shale samples by sound velocity measurements parallel and perpendicular to the bedding. In the montmorillonite the velocities parallel and perpendicular to the bedding were 2.12 and 1.92 km/sec respectively, a difference of about 11%; in the shale the same velocity measurements were 4.18 and 3.75 km/sec, a difference again of about 11%. Within the bedding plane the sound velocity was also found to be independent of direction. The electron photomicrographs of the montmorillonite sample, which are shown in Fig. l(a) and (b), clearly indicate the preferred orientation of the mica-like clay particles parallel to the bedding. In Fig. 2(a) and (b) similar orientation in the shale sample can be seen although not quite as clearly. This is probably because, in addition to the clays illite and chlorite, the shale sample contains grains of quartz, calcite and dolomite which do not as readily show an alignment pattern as the clays do. This suggests that the elastic anisotropy of these two samples is derived from a preferred alignment of component mineral grains which are themselves elastically anisotropic. The bulk elastic properties of these two samples therefore appear to be much like those of mica. Velocity measurements were made on the kaolinite sample in three directions at right angles because no bedding could be discerned in it. The values ob-

Jan 1, 1967

By J. L. Brimhall, R. A. Huggins

The structure of deformed internally oxidized alloys of siluer- cotztcrining magnesium and copper-containing aluminum in was studied by thin-film transrrzissiotz electron microscopy. With low to moderate amounts of stvain, the deformation structure in t11e dispersion-hardened alloys was found to consist of a high density of dislocations arranged it a random distribution or in a very fine, but poorly defined, cell stucture, depending on the fitness of the dbsbersion and amount of deformation. 112 contrarst, both pure copper and silver show relative1y Large, distinct cell structures. The particular structures in the alloys are believed to result from particles acting as both dislocaliot~ sources and deflector-s. The Inck of a pvorzolrr~ced deformation texture tr~ regiotzs qf' seoere loctll plastic curvature after heavy deformation can also be traced to the formation of clislocntions on many slip systemes and a lack 01 local concentrations of dislocations of predominantly one sign. THE presence of fine dispersions of a second phase has long been known to have a strong influence upon the mechanical properties of solids. Until recently, the influence of particles on the deformation mechanisms has been assumed to be solely that of barriers to dislocations. This is seen in the classic models of edge dislocations being restrained by the particles.1 4 There is, however, considerable evidence that this is not their primary effect, and that the particles can have a large influence on the defect structure generated by plastic deformation. The presence of particles causes changes in the surface topography observed after deformation. In overaged precipitation-hardened materials containing hard, noncoherent precipitates, fine intersecting slip lines are found after deformation of single crystals. indicating the activation of many slip systems. This has been extensively observed in the A1-Cu systen;, both by optical microscopy and replica electron microscopy.'"13 In some of the observations. the slip lines were seen to extend between the particles. Similar observations of extremely fine slip lines or the apparent absence of normal slip lines have also been found in A~-M~."

Jan 1, 1965

By K. A. Jackson

An analysis of the conditiom fm the dendrite-eutec-tic transition is presented which takes into account a temperature gradient. The composition and temperature in the liquid ahead of a eutectic interface growing at a particular velocity are used to determine whether dendrites can grow faster than the eutectic interface in the liquid which exists ahead of it. If the dendrites grow faster, then a mixed structure with dendrites growing ahead of the eutectic interface is expected. If the dendrites do not grow faster, then only eutectic will be present. The analysis is presented for Sn-Pb system, for which sufficient experimental data to make the analysis are available. The transition from eutectic to dendrites-plus-eutectic derived by this analysis is in good agreement with the recent experimental observations of Mollard and Flemings on Sn-Pb alloys. In alloys which grow with a lamellar eutectic structure, the lamellar structure can be grown over some range of compositions close to the eutectic composition. When the composition is too far from the eutectic composition, dendrites of one or another of the primary phases grow ahead of the eutectic interface, producing a microstructure consisting of "primary phase" interspersed with a lamellar eutectic. Hunt and Jackson' have recently predicted the range of compositions over which the eutectic phase should grow in Sn-Pb alloys, and the composition-growth rate dependence of the transition from eutectic to dendrites-plus-eutectic. This prediction was based on work on organic eutectics. The model on which the prediction was based assumed that there was no temperature gradient in the system, a condition approximately satisfied in the study of organic eutectics2-5 but not in the growth of metallic alloys. Mollard and Flemings6,7 have recently reported experimental results for Sn-Pb alloys in which they have located the transition from eutectic to eutectic-plus-dendritic growth. The experiments were performed using large temperature gradients (65 to 515 deg per cm), so that the assumption of zero gradient on which the predictions of Hunt and Jackson' were based does not apply. It is not surprising therefore that the predictions' were not born out by the experiments.7 In the present work, a modification of the model used by Hunt and Jackson is presented which takes into account the temperature gradient. The modified form of the theory predicts the transition from eutectic to eutectic-plus-dendritic growth in terms of the composition, growth rate, and temperature gradient. Good agreement with the experimental data of Mollard and Flemings7 is obtained. THE HUNT-JACKSON MODEL The model used by Hunt and Jackson' to predict the transition from eutectic to eutectic-plus-dendritic growth was based on the assumption that dendrites grow ahead of a eutectic interface only if they grow faster than the eutectic interface. Analytic expressions for the growth rate of dendrites and the eutectic in Sn-Pb alloys were obtained by fitting experimental data with equations whose form was indicated by theory.

Jan 1, 1969

By Irving Cadoff, Richard Nolder

An analysis oj a series of samples of single -crystal silicon grown on sapphire shows that ,four distinct orientation relations exist. There are at least thirteen crystallographic planes which serve as substrates ,for epitaxial growth The model which assumes that silicon substitutes for aluminium and bonds with the oxygen atoms of the sapphire to form the first later for subsequent growth can account for the epitaxial geometry in all four cases. Multiplici-ties 01 specific orientations are found which are explained by the symmetry of both the sapphire and silicon crystal structures. It was reported in the previous paper' that single-crystal silicon films can be deposited on single-crystal a A1,03 (sapphire) with a wide variety of orientations. The silicon films, however, were found to deposit in only four different orientation relationships with respect to the sapphire substrate. The X-ray data have been analyzed to determine the plane and direction of atomic fit and an atomic model to account for the epitaxial relationships at the silicon-sapphire interface has been developed. These results are described in the present paper. EXPERIMENTAL The Laue X-ray data described in the previous paper were reduced to stereographic projections in a standard manner. These data were supplemented with X-ray reflection data obtained with -& E and A Full-Circle Goniometer (Electronics and Alloys, Inc.) mounted on a Phillips diffractometer unit. The silicon films were thin enough to result in characteristic reflections from the substrate as well as the silicon. The superimposed stereographic projections were analyzed to determine the orientation relationships. Ambiguities were resolved by referring to constructed models of various lattice planes for both silicon and sapphire. These lattice models were also used to develop the model for atom fit at the interface. DATA AND ANALYSIS 1) Crystal Structures. The crystallography of silico-n, which is of the diamond cubic class with a. = 5.4~, is straightforward. The sapphire structure is more complex and generally difficult to represent in pictorial form. It is of the rhombohedra1 class but usually referred to hexagonal axes. The transformation of indices between these two systems can lead to ambiguities which will have bearing on the analysis presented herein. Therefore, the basis used in this paper is described in the appendix. Referred to the hexagonal system, the parameters of sapphire are co = 12.95.&, a, = 4.75~, c/a = 2.73. All parameters are for room temperature. Figs. 1 and 2 illustrate schematically the hexagonal unit cell model of sapphire used for this analysis. The oxygen atoms are assumed to occupy positions in an idealized hexagonal array on basal planes. Their actual positions are in a slightly distorted hexagonal array. The aluminum-atom positions are scaled to their actual positions in the lattice with respect to the basal layers of oxygen atoms. It was found that an idealized model where the aluminum atoms are assumed to lie exactly at the octahedral interstices of the oxygen lattice, similar to that used by ~ronberg,' was not adequate for this study.

Jan 1, 1965

Jan 1, 1963

The object of crushing and grinding for leaching is obviously to permit contact of the solvent and mineral and subsequent removal of pregnant solution in a reasonable time. Heap leaching is the leaching of ores that have been mined and transported to prepared, relatively impervious pads for leaching by sprinkling or ponding, and percolation of the lixiviate through the ore. Dump leaching is the leaching of dumps or low-grade ore or overburden without the use of prepared pads under them. Run-of-mine material, e. g., low -grade ore from open pit stripping operations, may be leached without crushing, and a fairly high recovery made by heap leaching. An alternate method for better grade gold/silver ores is to crush to 9 to 13 mm (318 to112 in. ) size for pad heap leaching, as used by Smoky Valley Mining Company at Round Mountain, Nevada, on gold ore, and to 38 rnrn (1 -1 12 in.), which will be done by Candelaria Partners, at Candelaria, Nevada, on silver ore. Heap leaching of copper probably began at Rio Tinto, Spain, about the year 1752. This was done by the leaching of weathering piles of ore in the open air followed by iron cementation of the liquor that drained off the heaps. Its application to the low -grade southwestern United States copper ores was overlooked for many years, and low- grade ores from Sacramento Hill at Bisbee, Arizona, were the first to be heap leached in 1923. Site preparation used a half century ago is the same today. "The need for some form of waterproofing of the pad was evident. Before leaching ore was piled, the site was cleared of cactus and brush. After clearing a gentle sloping area, it was then covered with a blanket of rolled and tamped clay or slime tailing. When heaps are built, a layer of coarse fragments may be put down first to assist drainage. A second method of leaching without grinding, usually for higher grade ores, is by vat or tank leaching of material crushed to 9 to 13 mm (318 to 112 in.) size. Such a plant is considerably more expensive than a heap leaching installation but much less costly than grinding for agitation leaching, and a recovery higher than that obtained by heap leaching is to be expected. Vat leaching has been widely used by the copper industry on higher grade copper ores but has been used in only a few small operations on that size gold or silver ores. However, such a plant should be considered for a modest tonnage of a few million tons, 3 to 7 g per mt (0.10 to 0.20 oz per st), of Carlin-type leachable ores crushed to 9 mm (318 in.).

Jan 1, 1981

The 118th meeting of the Institute was under the auspices of the Institute of Metals Division and the Iron and Steel Section, and was held at Milwaukee, Wis. The opening session was a joint meeting with the American Foundrymen's Association and the American Malleable Castings Association, and was presided over by Benjamin D. Fuller, President of the American Foundrymen's Association. At this time Hon. Emanuel

Jan 12, 1918

Jan 1, 1946

By William E. Ford, Edward Salisbury Dana

I. Sul~harsenites, Sulphantimonites, etc. In these sulpho-salts, as further explained on p. 320, sulphur takes the place of the oxygen in the commoner and better understood oxygen acids (as carbonic acid, H2COs, sulphuric acid, H4S04, phosphoric acid, H3P04, etc.). The species included are salts of the sulpho-acids of trivalent arsenic, antimony and bismuth. The most important acids are the ortho-acids,

Jan 1, 1922