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By Alfred H. Brooks

LESS than a decade ago the consumption of coal in Alaska was practically limited to the salmon canneries and the few lode-mines and settlements along the Pacific coast of the Ter¬ritory. The sparse population of the interior depended on the forests, that of the shores of Bering Sea and the Arctic Ocean on driftwood for fuel. All this has changed. The thousands who have sought and mined gold on the Seward peninsula since 1898 have much impoverished the long-accumulated supply of driftwood, and at the same time the constantly increasing demand for fuel, on the part of the placer-camps and steamers, has resulted in heavy inroads being made on the accessible timber of the Yukon and its tributaries. While on the one hand the immediately available store of wood has decreased, on the other the consumption of fuel because of the rapid expansion of the mining and fishery industries and the attendant growth of population has much increased. Alaska, therefore, offers a constantly growing market for coal and other fuels. As the local coal-production has been insignificant, the demand has been met by importations from Washington, British Columbia, and even from Pennsylvania and Australia. Fuel-Consumption Mr. D. H. Jarvis, Collector for Alaska, has kept systematic records of the trade of the Territory since 1903. The statistics of the coal-importations of the past two years are shown in Table I. If data were available for a longer period of years, the increase of coal-importations would be much more striking.

Jul 1, 1905

By Louis Moyd

The Concrete Research Division, U.S. Corps of Engineers, has developed a simple procedure for determining the coefficients of linear thermal expansion of rocks by means of resistance wire (SR-4) strain gauges. Gauges are cemented to the surfaces of specimens, which are then brought alternately to temperatures of 35OF and 1350F. Results are accurate to the seventh decimal place. IN the course of investigations of the thermal properties of various rocks proposed for use as aggregates in concrete structures, a relatively rapid method of determining coefficients of linear thermal expansion was required. A method which proved to be satisfactory for this purpose was developed in the petrographic laboratory of the Concrete Research Division, U.S. Corps of Engineers, at Clinton, Miss. The method is based on the fact that strain effects in a specimen can be determined by measuring variations in the resistance of an electrical conductor firmly cemented to the surface of the specimen. Equipment for the determination of strain, electrically, has been developed by the Baldwin-South-wark Division of the Baldwin Locomotive Works in Philadelphia. This equipment includes small strain gauges made of coils of resistance wire bonded between thin sheets of paper (SR-4 gauges), and a portable "Strain Indicator" which records variations in the length of the gauges in microinches per inch. Gauges of this type are now in general use for determinations of various mechanically-induced strains, but their use for the determination of coefficients of thermal expansion appears to be a new application. The advantages of the method are that the test specimens may be relatively small and require only a minor amount of preparation, that a large number of tests can be run at the same time, and that the installation and operation of the equipment is relatively simple. The method and equipment described are now in regular use for determining the coefficients of linear thermal expansion of rock samples submitted to this laboratory. Rocks which have been tested include granites, syenites, gabbros, and other igneous rocks, limestones and dolomitic limestones, sandstones, and quartzites. Specimen Preparation: To standardize the conditions of the tests, the rock specimens are sliced by diamond saw into slabs about 11/2x11/4 in. In the case of bedded or foliated rocks, three oriented slabs are cut from the same specimen, and represent, respectively, a direction in a plane of the bedding or foliation of the rock; a direction along the bedding or foliation and at a right angle to the first; and a direction across the planes of bedding or foliation. One of the large surfaces of each slab is lapped for a few minutes with No. 100 abrasive powder to remove saw scars and irregularities. The slabs are soaked in petroleum ether and then dried in an oven to remove all traces of oil picked up in the sawing

Jan 1, 1951

By Louis Moyd

The Concrete Research Division, U.S. Corps of Engineers, has developed a simple procedure for determining the coefficients of linear thermal expansion of rocks by means of resistance wire (SR-4) strain gauges. Gauges are cemented to the surfaces of specimens, which are then brought alternately to temperatures of 35OF and 1350F. Results are accurate to the seventh decimal place. IN the course of investigations of the thermal properties of various rocks proposed for use as aggregates in concrete structures, a relatively rapid method of determining coefficients of linear thermal expansion was required. A method which proved to be satisfactory for this purpose was developed in the petrographic laboratory of the Concrete Research Division, U.S. Corps of Engineers, at Clinton, Miss. The method is based on the fact that strain effects in a specimen can be determined by measuring variations in the resistance of an electrical conductor firmly cemented to the surface of the specimen. Equipment for the determination of strain, electrically, has been developed by the Baldwin-South-wark Division of the Baldwin Locomotive Works in Philadelphia. This equipment includes small strain gauges made of coils of resistance wire bonded between thin sheets of paper (SR-4 gauges), and a portable "Strain Indicator" which records variations in the length of the gauges in microinches per inch. Gauges of this type are now in general use for determinations of various mechanically-induced strains, but their use for the determination of coefficients of thermal expansion appears to be a new application. The advantages of the method are that the test specimens may be relatively small and require only a minor amount of preparation, that a large number of tests can be run at the same time, and that the installation and operation of the equipment is relatively simple. The method and equipment described are now in regular use for determining the coefficients of linear thermal expansion of rock samples submitted to this laboratory. Rocks which have been tested include granites, syenites, gabbros, and other igneous rocks, limestones and dolomitic limestones, sandstones, and quartzites. Specimen Preparation: To standardize the conditions of the tests, the rock specimens are sliced by diamond saw into slabs about 11/2x11/4 in. In the case of bedded or foliated rocks, three oriented slabs are cut from the same specimen, and represent, respectively, a direction in a plane of the bedding or foliation of the rock; a direction along the bedding or foliation and at a right angle to the first; and a direction across the planes of bedding or foliation. One of the large surfaces of each slab is lapped for a few minutes with No. 100 abrasive powder to remove saw scars and irregularities. The slabs are soaked in petroleum ether and then dried in an oven to remove all traces of oil picked up in the sawing

Jan 1, 1951

By M. C. Udy, F. W. Boulger

AN incomplete phase diagram for the U-Ti systern was determined earlier 1 and more recently, a tentative diagram was presented for the uranium-rich end of the system.' In the present re-examination of the whole system of U-Ti alloys, high purity materials were used. Melting stock for the alloys was high purity uranium, containing about 0.09 pct C as the only appreciable impurity, and high purity iodide-process titanium purchased from New Jersey Zinc Co. Both metals were cold rolled to about 1/6 in. thickness, sheared to about I/' in. squares, and cleaned by pickling. The alloys were arc melted under a helium atmosphere in a water-cooled copper crucible. A thoriated-tungsten electrode was used. The furnace chamber was evacuated, then flushed with helium, prior to each melting. It was finally filled with stagnant helium at one atmosphere pressure. Each alloy was remelted three times after the original melting, to insure homogeneity. The alloy button was turned bottom side up before each re-melting operation. Some 22 alloys were examined. Their compositions were spaced at appropriate intervals between 100 pct Ti and 100 pct U. Analyses were made on chips taken after fabrication. The major contaminant was carbon, which varied from 0.03 to 0.08 pct. It appeared in the microstructure as titanium carbide. Alloy compositions were calculated to a carbon-free basis for consideration on the diagram. Tungsten and copper, possible contaminants from the melting operation, were generally less than 100 parts per million each. Fabrication All alloys were forged and rolled to bars approximately V8 in. square. They were clad either in SAE 1020 steel or in a 5 pct Cr-3 pct Al-Ti-base alloy, depending on the fabrication temperature. A temperature of 1800°F (980°C) was used for alloys near the compound composition. This necessitated using the titanium-base alloy, since iron reacts with titanium at this temperature, producing a low melting alloy. Other alloys were fabricated at 1450°F (790°C), using steel jackets. No iron-titanium reaction occurred at this temperature. The jackets were welded in place in an argon atmosphere. Those alloys sheathed in steel were declad and then reclad between rolling and forging operations. On the other hand, those clad with the titanium alloy were cut to a roughly rectangular shape prior to clading and were then carried through both the forging and rolling operations without opening. Those alloys near the compound composition were found to be cracked when the clading was removed. The cracked materials had been plastically deformed, however, and at least some of the cracking had OCcurred during cooling. Heat Treatment The rolled bars, after being declad and shaped to remove surface contamination, were all given an homogenizing treatment of 160 hr at 2000°F. (Samples were taken for analysis following the declading and shaping operations.) All were heat treated at the same time in one furnace, but each was sealed in a purified argon atmosphere in an individual Vycor glass tube. Argon pressure was such that it was approximately atmospheric at temperature. One end of each tube contained titanium chips and this end was heated to 1200°F (650°C) for 10 min prior to the heat treatment. This purged the atmosphere of residual reactive gases. The balance of the tube was warmed during the purge to liberate adsorbed moisture and gases, which also reacted with the hot chips. The bars were furnace cooled from the homogenization treatment. Specimens of each alloy were water quenched after 2 hr heating at 1000°, 1200°, 1400°, 1600°, 1800°, and 2000°F (540°, 650°, 760°, 870°, 980°, and 1095°C). In addition, some were treated at intermediate temperatures of 1300°, 1500°, and 1700°F (705", 815", and 925°C) and at 2150°F (1175°C). Specimens, about '/s in. cubes, were cut from the bars, sealed in individual Vycor tubes, and heat treated as described. All specimens heat treated at the same temperature were processed together. Samples were quenched by breaking the Vycor tube rapidly under water. Metallographic Examination Specimens were mounted in bakelite and ground wet on 180 grit paper held on a 1750 rpm disk. They were then ground wet by hand, using 240, 400, and 600 grit papers. The rough grinding was continued long enough to get well below the surface. Specimens were mounted separately because of the variation in the rate of etching between alloys. The specimens were polished with rouge on a 4 in., 1725 rpm wheel covered with Miracloth. Alloys on the titanium side of the compound composition were etched with a solution of 2 pct hydrofluoric acid in water saturated with oxalic acid. A few crystals of ferric nitrate were added as a bright -ener. Specimens were immersed 5 sec, polished to remove the etch, then re-etched. With the higher titanium alloys, it was often necessary to start the etch on the polishing wheel, because of the formation of a passive film. In some instances, a plain 2 pct hydrofluoric etch was satisfactory. For the alloys on the uranium side of the compound, a distinction between the compound and the uranium phase developed after standing a short time in air. This could be hastened by the application of heat, such as obtained by placing the specimen on a radiator. A deep etch was necessary to develop details in the uranium-rich phase, such as the Widmanstaetten pattern sometimes obtained by quenching y uranium. A 2 pct hydrofluoric acid solution was used for this deep etching.

Jan 1, 1955

By J. Jones-Parra

In previous Technical Notes, W. R. Rose' and W. Purcell have discussed the capillary pressure data presented by Welge.' Welge obtained capillary pressure curves of the imbibition type in which it was necessary to apply to the apparent wetting phase a greater pressure than that of the non-wetting phase to complete the cycle and reduce the non-wetting phase saturation to low values. Rose suggests in his Note that conditions of equilibrium could not have prevailed, since the. non-wetting phase pressure must always be the greater. Pur-cell in his Note, proceeds to postulate a pore system consisting. of a series of "holes in a doughnut," in which he contends that under equilibrium conditions it is necessary to resort to negative capillary pressures before significant wetting phase displacement can take place. There is a remarkable similarity between the shape of the capillary pressure curve calculated by Purcell and those measured by Welge. It is the purpose of this Note to show that, because Purcell neglected to account for the behavior of the residual wetting phase saturation, his system was not in equilibrium during imbibition; and, furthermore, that if his system had been in equilibrium, negative capillary pressures would not have been possible. In Purcell's pore system, the residual wetting phase will form pendular rings at the interstitial spaces existing somewhere within the system, for example, such as those spaces between "doughnuts" as shown in Fig. 1. The true capillary pressure is that across the pendular ring interface, and for the system to be in equilibrium the pressure drop across all interfaces must be the same, including that across the interface in the tight pores A of diaphragm B (Fig. 1). As the pressure across the cell is reduced, the advancing interface will move into the pore from the diaphragm, but at each pressure, the curvature of the pendular rings must be the same as that of the advancing interface if equilibrium is to prevail. Since equilibrium conditions are the basis for the entire argument, it follows that pendular rings must grow as wetting phase enters the pore, that is, as the pressure across the cell is lowered. In Purcell's calculated curve, the residual wetting phase saturation remains constant as the capillary pressure decreases. Thus, his curve does not represent an equilibrium process.

Jan 1, 1953

By S. F. Reiter, You-Chao Liu, W. R. Hibbard

Cyril Stanley Smith in his classic 1948 Institute of Metals Lecture&apos; noted in the case of annealing twins that: "It is well known that approximately the same number of twins per grain and the same general geometry are maintained in large grains as in small ones, a fact that certainly suggests a mechanism such as the above where boundaries and twins grow proportionately together. If this view is correct, a spherical grain should have no mechanism for keeping its twins." Such a constancy of twins per grain would be of particular interest as a tool for the study of the origin of annealing twins. It has been proposed by Mathewson2 and later by Barrett3 that in face-centered cubic metals slip occurs in the {111} Plane by <112> shears which combine in pairs to produce the macroscopically observed <110> movement. This proposal is schematically inviting since <112> slip permits the atoms of one plane to move along the interatomic valleys of its neighbor rather than up the hills across the atom sites. There is strong experimental evidence? that annealing twins result from the growth of nuclei in the form of "twin faults" produced by single <112> shears. It is possible that more twin faults would form at low deformation temperatures than at high ones, because the more rigid lattice may increase the tendency to "freeze" the twin faults and prevent their dissipation in slip. This is suggested by (1) the greater resistance to slip at low temperatures and (2) greater tendency toward mechanical type twinning at low temperatures (a summary of these factors is presented by Seigle and Brick5). These considerations would suggest the following: a. Constant twin/grain ratio for specimens deformed constant amounts at a constant temperature, but annealed at various temperatures above the recrystalliza-tion temperature. b. Larger twin/grain ratios for re-crystallized specimens previously deformed constant amounts at lower temperatures. The purpose of this investigation is to test these considerations. One half in. rods of phosphorous deoxidized electrolytic copper and 70-30 alpha brass (68.36 pct Cu, 0.005 pct Pb, 0.01 pct Fe, 31.62 pct Zn remainder) were rolled to a thickness of 0.350 in., milled to specimens 0.350 X 0.437 X 2 in., and annealed at 700°C to an average grain size of 0.065 and 0.090 mm, respectively. These specimens of each metal were then rolled 50 pct reduction in thickness and annealed one hour under conditions which were all combinations of the following: Rolling Annealing Temperatures. Temperatures. °C °C -70 400 25 500 200 600 Standard metallographic techniques&apos; were used to prepare specimens. By the method of lineal analysis7 using a minimum of ten samples of fifty grains each for each specimen, the ratios of twins* per total grains, twins per twinned grain, twin families* per total grains and twins per twin family were determined. Recrystallized grain size was determined by A.S.T.M. comparison methods.8 All observations were made on the rolling plane. The results are tabulated in Table 1.

Jan 1, 1950

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who called at Institute headquarters during the period August 1, 1916 to September 10, 1916: C. L. Cantley, New Glasgow, N. S. H. M. La Follette, La Follette, Tenn. D. A. Cowell, Columbus, Ohio. Montrose L. Lee, Montevideo, Uruguay. Alexander Deussen, Houston, Texas. V. H. McNutt, Billings, Mont. Chas. E. Dutton, Goldfield, Nev. J. W. Maller, New York, N. Y. H. S. Emlaw, Grand Haven, Mich. Edwin W. Mills, Tul. Mi Chung, Chosen, J. M. Gillette, Swatsburg, N. Y. Korea. E. Gorilla, San Antonio, Texas. Francis R. Pine, Elizabeth N. J. Bertram Grant, Kingman, Arizona. Frank A. Ray, Columbus, Ohio. Ruger W. Hay, Bisbee, Arizona. John A. Rice, El Paso, Texas. C. F. Hendricks, Cobalt, Ontario. W. E. Rice, Ringwood Manor, N. J. Stanley C. Herold, San Jose, Cal. W. H. Staver, Lynchburg, Va. Lloyd Hoffman, Pottersville, N. J. Ralph H. Sweetser, Easton, Pa. Charles Hunter, London, England. Kirby Thomas, New York, N. Y. G. Jansen, Benkoelen, Sumatra. Henry Traphagen, Union Hill. T. H. Jenks, Oatman, Arizona. M. M. Valerius, Tulsa, Okla. Warren jenny, Chanaral, Chile. Wilfrid B. Wainewright, London, Eng. Walter A. Barrows, Jr., of Brainerd, Minn., has been elected president and general manager of the Thomas Iron Co., Easton, Pa., to succeed Ralph H. Sweetser, whose resignation of several months ago becomes

Jan 10, 1916

The following is an incomplete list of members and guests who called at Institute headquarters during the period June 10, 1919, to July 10, 1919. Anvil A. Anderson, Rapid City, S. D. Roy N. McBride, U. S. Army. R. Hay Anderson, Mexico City, Mex. R. S. McIntyre, Berkeley, Calif. W. A. Barnes, San Francisco, Calif. H. R. Maier, Brooklyn, N. Y. Bennett R. Bates, Denver, Colo. Wm. D. Mainwaring, Philadelphia, Pa. Harlan H. Bradt, Duluth, Minn. Wm. E. Milligan, Chrome, N. J. H. Brings, San Francisco, Calif. Willard S. Morse, Tacoma, Wash. Robert S. Burg, Ocean Park, Calif. Arthur Notman, Bisbee, Ariz. D. W. Butner, Congo Belge, Africa. P. Nugue, Chalon Sr. Saone, France. George A. Camphuis, El Paso, Tex. George A. Packard, Boston, Mass. Fred Canan, Denver, Colo. C. L. Petzel, New York City. Walter H. Coleman, Prescott, Ariz. V. Porreaud, Paris, France. Fred Crabtree, Pittsburgh, Pa. Fred S. Porter, Seattle, Wash. Ross E. Douglas, Rancagua, Chile. R. W. Prouty, Morenci, Ariz. F. A. Downes, Golden, Colo. Charles E. Prior, Brooklyn, N. Y. W. G. Eberhardt, Tucson, Ariz. Louis Ravicz, Minneapolis, Minn. Charles H. Fulton, Cleveland, Ohio. Wm. Reed, El Oro, Mexico. Wm. R. Grunow, New York City. E. J. Ristedt, Globe, Ariz. Orr R. Hamilton, Lansing, Mich. A. M. Rodgers, Middletown, N. Y. T. N. Havlin, St. Louis, Mo. J. C. Scoles, Salt Lake City, Utah. G. M. Henderson, Weston, Mass. C. E. Siebenthal, Washington, D. C.

Jan 8, 1919

The following list comprises the names of those persons who became members during the period Sept. 10, 1919, to Oct. 10, 1919. ADAMS, R. L Chief Min. Engr., Old Ben Coal Corpn., Mine 12, Christopher, Ill. Arizumi, Hiroshi The Kuhara Min. Co., Ltd., Tokyo, Japan. BAILY, T. F Pres. & Gen&apos;l Mgr., Electric Furnace Co., Alliance, 0. BALDWIN, A. J., Min. Engr Box 145, Pikeville, Kentucky. BALTZELL, WILL H., Chief Engr., Canadian Steel Corpn., Ltd., Ojibway, Essex Co., Ont., Canada. BANON, E. MAGAWLY, Examining Engr., Dawes Bros., Inc. 108 So. LaSalle St., Chicago, Ill. BARNES, W., Mech. Engr., Excavating Dept., Ruston & Hornsby, Ltd., Lincoln, England. BASHORE, E. GORGAS, Head Chem., The Babcock & Wilcox Co., Bayonne, N. J. BASS, A. L Supt., Hobson Silver Lead Co., Ltd., Ymir, B. C., Canada. BORN, SIDNEY, Chief Chem., Empire Gas & Fuel Co. & Associated Companies, 1100 Cherokee Ave., Bartlesville, Okla. BRADLEY, J. G,, Coal Operator, Pres.,& Gen&apos;l Mgr., Elk River Coal & Lumber Co., Dundon, W. Va. BENNETT, G. W., Min. Engr., Sales Engr., Taylor-Wharton Iron &- Steel Co., High Bridge,. N. J. BRUFF, CHARLES E., Member firm Bradley, Bruff & Labarthe, 85 Second St., San Francisco, Cal. COLLINS, FRANK W., Chief Engr., Bradley, Bruff & Labarthe, 85 Second St., San Francisco, Cal. CONNELL, F. M., Min. Engr., Eastern Alin. & Mill. Co., Ltd., 905 Bank of Hamilton Bldg., Toronto, Ont., Canada. CooK, HARRY H., Vice-pres., Valley Mould & Iron Corgn., 137 Shenango St., Sharpsville, Pa.

Jan 11, 1919

By David J. Mack

A SURVEY and critical appraisal of published information about Young&apos;s modulus was originally made by the writer because of a complete lack of information about this very important quantity in works on mechanics, physical metallurgy, physics, and other sciences. It was felt that a comprehensive summary of such information about Young&apos;s modulus might be of general interest and may suggest new problems or lines of attack on other problems that involve E. Hence this paper has been prepared even though it is only a review, with no new ideas or experimental data. The references are only those used in assembling the paper. No attempt was made to compile a complete bibliography on the subject of Young&apos;s modulus. CALCULATION OF YOUNG&apos;S MODULUS FROM THEORETICAL OR EMPIRICAL CONSIDERATIONS Many attempts have been made to compute E from theoretical considerations. The earliest calculations were probably those of Tomlenson (1883) and Southerland (1891), but Fessenden 41,42 made extensive calculations a few years later and arrived at the relationship: [2E = 78. 101 (_L V] where V is the atomic volume. In 1923, Peczalski,43 working from the same stand-point but with more information available on atomic structure, arrived at an identical relationship, which he expressed as: [E=B(m) 2] where B is a constant of value about 8 • 10 7, p is density and m is atomic weight; the atomic volume, of course, being m/p. Portevin44 immediately pointed out that while the equations of Fessenden and Peczalski were true of the common metals, they gave low values for the refractory metals with high moduli (Fig. I). He showed (Fig. 2) that much better concordance was obtained by means of an empirical equation of the form: [E _ KT&apos;Vb] where K is a constant; T the absolute melting point; V, atomic volume, and a and b constants of value approximately I and 2 respectively. This constant K in the Portevin equation is not necessarily the same for all elements, as shown by Thompson.45 Other equations for E based upon theoretical considerations have been derived by Honda and Yamada49 and Lasareff. 50 The most recent calculations of elastic moduli based upon quantum mechanics are probably those of Fuchs.46-48 He extended the method of Wigner and Seitz for calculating the lattice energy and compressibility of monovalent metals and computed the elastic constants of lithium,

Jan 1, 1945

By AIME AIME

BECAUSE of its unequalled skill, your country in- creased its production until, in 1913, it produced 40 per cent. of the world&apos;s consumption of coal, iron ore, and cast iron; 45 per cent. of the steel; and 60 per cent. of the copper. Your industrial effort, in a general manner and your mining effort in particular, has been tremendous. In the general economy of the world, you occupy an incomparable position of power and action. All your curves of production, mineralogical, metallurgical, financial, commercial, have taken terrific trigonometrical tangents and you will easily under- stand the sorry position of your competitors. I must, therefore, pay a tribute of homage arid admiration to you all who, each in his sphere, have been the artisans of such prosperity and my earnest wish is that you continue in this way.

Jan 1, 1920

By R. H. Olds, B. H. Sage

The formation volume and volume of the liquid phase of oil and gas obtained from four fields in the San Joaquin Valley have been investigated at pressures, temperature, and gas-oil ratios comparable to those encountered in underground reservoirs. All the fields covered in this investigation yielded a product of a gas-oil ratio in excess of 5000 cu ft per barrel and the gravity of the tank oil for the four fields in question varied between 52° and 63&apos; API. The results of the investigation, together with analytical data concerning the composition of the oil and gas, are submitted in tabular form. Rough correlations of the formation volume as a function of pressure, temperature, and gas-oil ratio and of the retrograde dew-point pressure as a function of gas-oil ratio, temperature, and gravity of tank oil are presented. It was not found feasible to correlate simply the formation volume of the liquid phase as a function of the applicable variable. It is desired to emphasize that these correlations are considered applicable only to the range of conditions covered in this investigation and for systems of similar nature and composition. Introduction Information concerning the physical properties of mixtures of oil and gas from particular fields have often been employed in predicting the situations obtaining in underground reservoirs. One of the earlier studies of this nature was the work of Beecher and Parkhurst,1 while a more recent study of the Dominguez Field2 presented detailed volumetric data in the two-phase as well as in the single-phase regions. Although these studies were confined to individual fields, their results proved of value in application to other fields. It has recently been shown 3,4 that it is possible in the region of low gas-oil ratios* to correlate the volumetric behavior of naturally occurring hydrocarbon mixtures from a single geographical area with sufficient accuracy to be of industrial value. For this reason it is considered of interest to submit information concerning the volumetric behavior of oil and gas mixtures from four different fields in the San Joaquin Valley and, in combination with similar published data5 concerning mixtures of oil and gas from the Paloma field in the same area, to show rough correlations between the composition and the behavior of materials from these fields. This effort seems particularly worth while since all of the

Jan 1, 1947

By R. H. Olds, B. H. Sage

The formation volume and volume of the liquid phase of oil and gas obtained from four fields in the San Joaquin Valley have been investigated at pressures, temperature, and gas-oil ratios comparable to those encountered in underground reservoirs. All the fields covered in this investigation yielded a product of a gas-oil ratio in excess of 5000 cu ft per barrel and the gravity of the tank oil for the four fields in question varied between 52° and 63&apos; API. The results of the investigation, together with analytical data concerning the composition of the oil and gas, are submitted in tabular form. Rough correlations of the formation volume as a function of pressure, temperature, and gas-oil ratio and of the retrograde dew-point pressure as a function of gas-oil ratio, temperature, and gravity of tank oil are presented. It was not found feasible to correlate simply the formation volume of the liquid phase as a function of the applicable variable. It is desired to emphasize that these correlations are considered applicable only to the range of conditions covered in this investigation and for systems of similar nature and composition. Introduction Information concerning the physical properties of mixtures of oil and gas from particular fields have often been employed in predicting the situations obtaining in underground reservoirs. One of the earlier studies of this nature was the work of Beecher and Parkhurst,1 while a more recent study of the Dominguez Field2 presented detailed volumetric data in the two-phase as well as in the single-phase regions. Although these studies were confined to individual fields, their results proved of value in application to other fields. It has recently been shown 3,4 that it is possible in the region of low gas-oil ratios* to correlate the volumetric behavior of naturally occurring hydrocarbon mixtures from a single geographical area with sufficient accuracy to be of industrial value. For this reason it is considered of interest to submit information concerning the volumetric behavior of oil and gas mixtures from four different fields in the San Joaquin Valley and, in combination with similar published data5 concerning mixtures of oil and gas from the Paloma field in the same area, to show rough correlations between the composition and the behavior of materials from these fields. This effort seems particularly worth while since all of the

Jan 1, 1947

By ALBERT P. J. BORDEAUX

THIS paper briefly describes the general outline of cyaniding silver-ores in Mexico, with special reference to personal experiments made in the Temascaltepec district. The most important papers on the subject deal with cyaniding gold-silver-ores, the gold predominating in value, so that the treatment is nearly the same as for gold-ores, the losses of silver being considered of little importance. I describe here the treatment of silver-gold-ores containing very little gold, which is more general in Mexico than elsewhere. The cyanide treatment, which was so successfully applied to gold-ores, did not succeed immediately with silver-ores on account of their varying composition. Gold occurs in nature usually in the native state, while silver occurs generally in combination with sulphur (argentite), and various combinations of sulphur, antimony, and arsenic. In former times there was a complete difference in the treatment of gold-ores and silver-ores. Amalgamation, which was successful with gold-ores, was generally inadequate with silver-ores. The usual treatment in Mexico for silver was the patio process, the theory of which was satisfactorily explained only quite recently by Mr. Ortega and others. GENERAL OUTLINE OP THE CYANIDE TREATMENT. The general tendency of the present practice is to slime the silver-ore as much as possible, and in order to obtain a higher efficiency, with less loss of cyanide, and greater speed, the following lines are observed 1. Crushing by stamps with 30- or 40-mesh screens, then crushing by Huntington or Chilean mills, through 60- or 80-mesh screens. 2. Concentration upon vanners.

Jan 1, 1910

By F. C. Canney

Geochemical prospecting seeks hidden mineral deposits by sampling for variations in the chemical composition of naturally occurring materials. Usually the samples are of soils and other products of weathering and erosion-surface materials extremely susceptible to contamination by human activities. Except when a survey is conducted well away from populated areas, contamination is an ever-present hazard. The program&apos;s success is particularly endangered when the contaminants are the elements sought; if these occur erratically throughout an area, spurious anomalies completely unrelated to mineralized areas can be formed. Evenly distributed contamination can be dangerous too, if it raises the background to such a level that true anomalies can no longer be easily detected. Suppose, for ex- ample, that in an area where the lead background is 20 parts per million the soil over a lead vein contains 1000 ppm of lead. Here the contrast would be 50 to 1, which is very satisfactory for geochemical surveying. Now if 1000 ppm of lead from some source were added evenly to the soil in this area, the contrast would be reduced to about 2 to 1, and the anomaly would no longer be readily detectable because a threshold of significance twice the value of the background is the minimum generally used for interpreting geochemical data.

Jan 2, 1959

By S. C. Sun

With the aid of emulsifiers, intense high-frequency sound waves are capable of emulsifying any collector in water. The data show also that ultrasonically emulsified collectors are more effective in floating minerals than the nonemulsified collectors. THE use of ultrasonics in forming emulsions is not new. As early as 1927 Wood and Loomis reported preparation of emulsions with ultrasonics. In 1935 Rschevkin and OstrawskyV escribed the use of great ultrasonic power in producing fine emulsions of various oils and paraffin in water. Recently Oyama and Tanaka3 employed ultra-emulsification to increase the effectiveness of sodium ethyl xanthate in flotation of chalcopyrite and galena. An emulsion is a two-phase system consisting of two incompletely miscible liquids, the one being dispersed as finite droplets In the other. The dispersed liquld is known as the internal or discontinuous phase, and the surrounding liquid is termed the external or continuous phase. There are two types of emulsions; one is oil-in-water (O/W) and the other water-in-oil (W/O). The word oil refers to the liquid other than water. Circumstances exist in which the emulsion type is not clearly defined, and the internal and external phases both contain portions of the opposite phase. This is said to be a dual emulsion. Among the many hypotheses, 5a, B proposed for the formation of emulsions, the Bancroft&apos;s adsorbed film or double interfacial tension theory is widely accepted. Bancroft 7, 8 deduced that in the process of emulsification the interfacial tension between oil and water is lowered by the formation of an emulsifying film, which contains the adsorbed molecules and/or ions from the emulsifying agent and the two liquids. This film has two interfacial tensions, one with the water and the other with the oil, which are not necessarily equal. The difference in interfacial tension between the two surfaces of the film is chiefly responsible for forming different types of emulsions. For example, if the interfacial tension between water and film is less than that between oil and film, the film will become convex on the water side, thereby tending to form an oil-in-water emulsion. On the other hand, if the interfacial tension between water and film is greater than that between oil and film, the film will become concave on the water side, thereby tending to make a water-in-oil emulsion. In line with this theory, emulsifying agents soluble in water have the tendency to form oil-in-water emulsions, while those soluble in oil form emulsions of the reverse type. Apparatus and Experimental Procedure: The ultrasonic apparatus shown in Fig. 1 consisted of a hypersonic generator (A), Brush Development Co. model Bu-204; a hypersonic transducer bowl (B) whose resonant frequency is 400 kc per sec; and a round-bottomed glass tube (C) of 2.2 cm ID and 21 cm in length. The acoustical output power of the hypersonic transducer bowl was standardized with a Hewlett Packard vacuum tube voltmeter, model 41 0B, across the hypersonic generator output. The glass tube, containing the materials to be emulsified, was placed 1 cm above the central surface of the transducer bowl, which was filled with water as shown in Fig. 2. Ultrasonic emulsification was performed in three steps, although a one-step method has been used: 1) emulsifying the predetermined amounts of col-

Jan 1, 1956

By C. G. Black

The purpose of this paper is to present data obtained from an investigation conducted on the grindability of coal by the American Society for Testing Materials Tentative Standard ball-mill method. This investigation has been conducted over a period of a year, during which time several hundred tests were run on a wide selection of different coals coming from Pennsylvania, Ohio, West Virginia and Kentucky. The data herewith presented tend to show that the tentative standard ball-mill method might give results that are misleading and that a volume measure might be more indicative of the true grindability of materials of varying specific gravity. A means whereby the time element might be reduced has been studied and other phases of this work such as preparation of samples, mechanical screening, reporting results and duplicating tests have been investigated. It is hoped that all criticism offered in this paper will be taken as constructive, with the purpose ill mind of perfecting the method now tentative to show the true conditions 2nd of making optional the manner in which certain parts of the test might be conducted to meet diversified laboratory conditions. Weight and Volume The results of grindability on extraneous material from the coal scam obtained with the present tentative standard ball mill method indicate easier grinding of these materials as compared to most coals. Varying amounts of these impurities in the coal therefore may cause a raising of the grindability index and may lead to the erroneous conclusion that coals containing large amounts of these foreign materials are easier to grind. For a true comparison of grindability, it would seem necessary to grind to the same particle weight. If material were sized in a commercial mill by means of an air current set at a velocity to remove 1.60 sp. gr. float coal ground to 80 per cent minus 200 mesh, any 1.60 sink particles would be left behind, and in order to remove this 1.60 sink material by the same current it would be necessary to grind finer and produce a

Jan 1, 1936

By C. G. Black

The purpose of this paper is to present data obtained from an investigation conducted on the grindability of coal by the American Society for Testing Materials Tentative Standard ball-mill method. This investigation has been conducted over a period of a year, during which time several hundred tests were run on a wide selection of different coals coming from Pennsylvania, Ohio, West Virginia and Kentucky. The data herewith presented tend to show that the tentative standard ball-mill method might give results that are misleading and that a volume measure might be more indicative of the true grindability of materials of varying specific gravity. A means whereby the time element might be reduced has been studied and other phases of this work such as preparation of samples, mechanical screening, reporting results and duplicating tests have been investigated. It is hoped that all criticism offered in this paper will be taken as constructive, with the purpose ill mind of perfecting the method now tentative to show the true conditions 2nd of making optional the manner in which certain parts of the test might be conducted to meet diversified laboratory conditions. Weight and Volume The results of grindability on extraneous material from the coal scam obtained with the present tentative standard ball mill method indicate easier grinding of these materials as compared to most coals. Varying amounts of these impurities in the coal therefore may cause a raising of the grindability index and may lead to the erroneous conclusion that coals containing large amounts of these foreign materials are easier to grind. For a true comparison of grindability, it would seem necessary to grind to the same particle weight. If material were sized in a commercial mill by means of an air current set at a velocity to remove 1.60 sp. gr. float coal ground to 80 per cent minus 200 mesh, any 1.60 sink particles would be left behind, and in order to remove this 1.60 sink material by the same current it would be necessary to grind finer and produce a

Jan 1, 1936

By L. G. Sprague

The fact that this latest and most modern of the Universal Atlas Cement Company&apos;s plants at Northampton, Pa., is the fifth to be built on these same properties, and their development has been coincidental with the development of the portland cement industry in the United States, makes it appropriate to sketch briefly the history of the successive steps. In 1889 the original Atlas Portland Cement Co. started its first plant at Coplay, Pa., which is just across the Lehigh River from the present operation. Here the first successful rotary kiln was operated. These kilns were 6 ft. in diameter and 60 ft. long; they used oil for fuel until 1895, when the company developed the first burner for pulverized coal. Shortly thereafter the Atlas company acquired property on the Northampton side of the river and built its plants Nos. 2, 3 and 4 within the following 10 years. During the same period the production of portland cement in the country was increasing rapidly; owing largely to the development of the rotary kiln and improved grinding machinery, which lowered the cost and improved the quality of cement. The general tendency has been to increase the length of the kiln and grind both raw material and finished product Liner. In 1930 the Atlas Portland Cement Co. and the Universal Portland Cement Co. united to form the Universal Atlas Cement Co., and the same policy of improving the product has been continued. Because of the large amount of research carried on by manufacturers and consumers, including government agencies, there is a demand for cement of different chemical and physical characteristics for different kinds of structures. Hence many engineers in recent years have been asking for cements of certain definite chemical analyses, which they think are best for their particular jobs. This has compelled the manufacturer to make several different types of cement by variations of chemical composition. These are generally made by adding silica, iron and lime to the standard mixture, which necessarily increases the cost of the product. Therefore the Universal Atlas Cement Co., in planning the modernization of its Northampton plant, gave this particular phase of the problem considerable study. Research and experimentation have developed the practicability of making a wide variety of differently proportioned raw materials for cement by a process of subtraction rather than by addition. With such process, it is possible to discard the undesirable aluminates and silicates from the ample supply of impure limestone available from the company&apos;s property rather than by adding high-grade limestone obtained from distant sources. This procedure requires mineral separation by centrifugal sedimentation and froth flotation. Since the chemical and mineral constituents of Lehigh Valley "cement rock," together with the methods of separating them, have been thoroughly described in published

Jan 1, 1948

By L. G. Sprague

THE fact that this latest and most modern of the Universal Atlas Cement Company&apos;s plants at Northampton, Pa., is the fifth to be built on these same properties, and their development has been coincidental with the development of the portland cement industry in the United States, makes it appropriate to sketch briefly the history of the successive steps. In 1889 the original Atlas Portland Cement Co. started its first plant at Coplay, Pa., which is just across the Lehigh River from the present operation. Here the first successful rotary kiln was operated. These kilns were 6 ft. in diameter and 60 ft. long; they used oil for fuel until 1895, when the company developed the first burner for pulverized coal. Shortly thereafter the Atlas company acquired property on the Northampton side of the river and built its plants Nos. 2, 3 and 4 within the following 10 years. During the same period the production of portland cement in the country was increasing rapidly; owing largely to the development of the rotary kiln and improved grinding machinery, which lowered the cost and improved the quality of cement. The general tendency has been to increase the length of the kiln and grind both raw material and finished product finer. In 1930 the Atlas Portland Cement Co. and the Universal Portland Cement Co. united to form the Universal Atlas Cement Co., and the same policy of improving the product has been continued. Because of the large amount of research carried on by manufacturers and consumers, including government agencies, there is a demand for cement of different chemical and physical characteristics for different kinds of structures. Hence many engineers in recent years have been asking for cements of certain definite chemical analyses, which they think are best for their particular jobs. This has compelled the manufacturer to make several different types of cement by variations of chemical composition. These are generally made by adding silica, iron and lime to the standard mixture, which necessarily increases the cost of the product. Therefore the Universal Atlas Cement Co., in planning the modernization of its Northampton plant, gave this particular phase of the problem considerable study. Research and experimentation have developed the practicability of making a wide variety of differently proportioned raw materials for cement by a process of subtraction rather than by addition. With such process, it is possible to discard the undesirable aluminates and silicates from the ample supply of impure limestone available from the company&apos;s property rather than by adding high-grade limestone obtained from distant sources. This procedure requires mineral separation by centrifugal sedimentation and froth flotation. Since the chemical and mineral constituents of Lehigh Valley "cement rock," together with the methods of separating them, have been thoroughly described in published

Jan 1, 1943