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THE distinction btween price reduction as a re-sult of lowering of production cost and price re-duction through unrestricted competition cannot be made too clear, because they are often interwoven in actual experience. Take the whole population of a town whose principal industry is shoe manufacturing as a concrete example. If the manufacturer is able to cut his price per pair in half because he has found out how to make a pair at half the cost, he will com-monly let a number of his men go, because reduction in production cost usually results from substituting cheap mechanical energy for expensive human energy. These people will normally find other employment. The workmen who remain employed usually earn more in dollars than they did before, and in spending it give employment where there was less before. Mining companies that initiate considerable enter-prises in foreign lands where the economic level is low, and where most of the people are busily but in-efficiently engaged in raising enough food to support themselves and their families, often find themselves confronted with an acute labor problem. If any con-siderable number of workers leave the land to work in and about the mines, those left on the land cannot raise enough food to keep them all unless they are taught better methods of agriculture and provided with equipment that will enable them to produce more with less expenditure of effort. Add to this the fact that managers commonly find that the "natives," as our British cousins designate them, usually need more food and a better balanced diet than they have been accustomed to in order to show anything above the lowest order of efficiency in industrial work,. and it is clear that to make a new industry possible in what may be termed an economic province involves increas-ing the productivity, not only of those who are em-ployed in it, but of the whole social group. It has already been pointed out that the employ-ment of large numbers of men in automobile manu-facture is only possible because the others have in-creased their productivity enough to turn out every-thing else that is needed without the help of the auto-mobile workers.

Jan 7, 1928

By Renato G. Bautista, Robert A. Hard

A comparative study has been made of the ex-tractability of several of the transitim metals from thiocyanate sohtions using methyl isobutyl ketone as the organic solvent. Extractions were made of scandium (III), chromium (III), manganese (II), iron (III), and cobalt (II), of which only the scandium , iron, and cobalt were readily extracted. All extractions were made at pH 2 and at 25.5 °C. A series of extraction experiments was made on scandium, iron, and cobalt to determine the effect of thiocyanate cmcentration added as the ammonium and also as the calcium salt. Also determined was the effect of metal ion concentratim and ionic strength on the distribution ratio. Analyses of the organic extracts indicated the scandium and iron were extracted principally in the uncharged trithiocyanate form, while the extractable form of the cobalt contained the cobaltotetrathiocyanate anion. THE chemical separation of metal complexes in solution by solvent extraction has in recent years been developed for large scale separation as well as bench scale work in the laboratory. It has also found increased application in analytical chemistry. Its extension to extractive metallurgy as a unit operation is best illustrated in the recovery of uranium and vanadium from their leached liquor.5-8 The extractability of some thiocyanate systems have been extensively investigated. The rate earths have been separated from one another using butanol as a olvent. Scandium was effectively extracted in ethyl ether using ammonium thiocyanate as the com-plexing agent.'' Similarly, the separation of hafnium from zirconium has been reported using ether""' or hexone13 as the organic solvent. The extractability of various metal thiocyanates in ethyl ether is given by 0ck.l Sharp and Wilkinson15 prepared nickel-free cobalt slats by thiocyanate extraction. The mechanism of extraction of titanium (IV) thiocyanate with methyl isobutyl ketone was determined by elafosse.''" The characterization of cobalt (TI) thiocyanate complex using methyl isobutyl ketone as the solvent at near neutral aqueous solution and the spectrometric studies of the ex-tractable cobalt complex has been made by Hard." It is noteworthy to mention at this point that the fundamental characteristic of ketone (oxonium) solvent extraction is that the extractable species are uncharged ion pairs solvated by the ketone molecules, but probably still partially hydrated.

Jan 1, 1963

J. Lainson Wills, Ottawa, Can. (Communication to the Secretary) : The localities of the Quebec and Ontario apatite deposits, and the nature of their occurrence haye been often described in the Transactions and in other publications that are readily available, and I do not, therefore, intend to discuss the many details advanced in Mr. Small's paper beyond the following two points:

Jan 1, 1893

By R. W. Gurry

When a steel in the austenitic state, with all its carbon in solution, is maintained, at constant temperature, in contact with a gas that removes the carbon from the surface, yet without otherwise altering the composition of the steel, the change in weight of the specimen, after any period of exposure, is a direct measure of the amount of carbon it has then lost. The purpose of the present paper is to show how, by application of established mathematical reasoning based on the fundamental diffusion law and on certain postulates, this loss of weight yields a complete picture of the distribution of carbon throughout a specimen of regular shape after any period of exposure, with all the accuracy required in any practical occurrence of decarburization. Precisely the same is true for the gain in weight during the reverse process of carburization, or for the gradual gain or loss of any element, so long as the steel comprises only a single phase at temperature, provided always that the experimental conditions conform to the postulates. The change in carbon content from surface to center of the specimen is always continuous, when everything is in solution, even though under the microscope the decarburized zone (or carburized rim) may appear to be sharply defined. The experimental procedure is described and some typical results are presented, which are then interpreted by application of the diffusion law. Experimental Procedure Initially an endeavor was made to follow the gain of weight during the process of carburization in a hydrogen-toluene atmosphere, but it was soon found that the specimen became coated with graphite, which could not be removed without some loss of metal; therefore it was decided to continue carburization until the steel was saturated throughout, to remove all graphite from the surface of the specimen, and then to follow the loss of weight during decarburization in a moist hydrogen atmosphere at the same temperature as that used for carburizing. The carburizing procedure has been described in an earlier paper;' it suffices to state here that the carburization lasted about I40 hr. at 760°C. (1760°F.) and 44 hr. at iiio°C. (2030°F.), these periods being long enough-—on the basis of the calculations presented later—to ensure that the specimen was about 99.9 per cent saturated at each temperature. The specimen was a cylinder about 3.8 cm. long and 0.475 cm. in diameter; the materials were carbonyl iron, a commercial low-metalloid iron, and a steel with 3.6 per cent nickel and the usual proportion of other elements. The fully carburized specimen, after cooling at the top of the furnace tube, was placed in a lathe and sandpapered to remove all graphite; then the diameter was measured with a micrometer caliper, and the initial weighing (corresponding to complete saturation) was made. By means of a

Jan 1, 1942

By R. W. Gurry

When a steel in the austenitic state, with all its carbon in solution, is maintained, at constant temperature, in contact with a gas that removes the carbon from the surface, yet without otherwise altering the composition of the steel, the change in weight of the specimen, after any period of exposure, is a direct measure of the amount of carbon it has then lost. The purpose of the present paper is to show how, by application of established mathematical reasoning based on the fundamental diffusion law and on certain postulates, this loss of weight yields a complete picture of the distribution of carbon throughout a specimen of regular shape after any period of exposure, with all the accuracy required in any practical occurrence of decarburization. Precisely the same is true for the gain in weight during the reverse process of carburization, or for the gradual gain or loss of any element, so long as the steel comprises only a single phase at temperature, provided always that the experimental conditions conform to the postulates. The change in carbon content from surface to center of the specimen is always continuous, when everything is in solution, even though under the microscope the decarburized zone (or carburized rim) may appear to be sharply defined. The experimental procedure is described and some typical results are presented, which are then interpreted by application of the diffusion law. Experimental Procedure Initially an endeavor was made to follow the gain of weight during the process of carburization in a hydrogen-toluene atmosphere, but it was soon found that the specimen became coated with graphite, which could not be removed without some loss of metal; therefore it was decided to continue carburization until the steel was saturated throughout, to remove all graphite from the surface of the specimen, and then to follow the loss of weight during decarburization in a moist hydrogen atmosphere at the same temperature as that used for carburizing. The carburizing procedure has been described in an earlier paper;' it suffices to state here that the carburization lasted about I40 hr. at 760°C. (1760°F.) and 44 hr. at iiio°C. (2030°F.), these periods being long enough-—on the basis of the calculations presented later—to ensure that the specimen was about 99.9 per cent saturated at each temperature. The specimen was a cylinder about 3.8 cm. long and 0.475 cm. in diameter; the materials were carbonyl iron, a commercial low-metalloid iron, and a steel with 3.6 per cent nickel and the usual proportion of other elements. The fully carburized specimen, after cooling at the top of the furnace tube, was placed in a lathe and sandpapered to remove all graphite; then the diameter was measured with a micrometer caliper, and the initial weighing (corresponding to complete saturation) was made. By means of a

Jan 1, 1942

By Ezequiel Ordoñez

The two mining districts of Pachuca and Real del Monte, well known for their antiquity and the extraordinary richness of their veins, are situated, 3 miles apart, only 62 miles north of the City of Mexico—the first being on the western, and the second on the eastern slope of the Pachuca range of mountains which bounds the great valley of Mexico. Close to the celebrated mining region of Pachuca is located the city of the same name, capital of the State of Hidalgo, at 2460 meters above sea-level and 20° 07' 35" North latitude, with 35,000 inhabitants, the majority of whom work in the mines; the remainder being Government employees, merchants, and a small number engaged in less important industries. The city extends along both sides of the canada which carries the waters of the river called "Avenidas de Pachuca," the banks of which are united by four bridges at regular intervals. The attention of the traveler approaching the city is first attracted by the appearance of the mountains, barren of vegetation, bounding the city with rocky cliffs and steep declivities, the grades of which serve as foundations to the irregular and varied groups of houses. Above these are the dumps, and, close by them, the mouths of the shafts, covered with conical tile roofs. The smoke of the chimneys, the noise of the mills and the appearance of some of the constructions reveal at first glance the industrial character of the place. At the left of the entrance to the canada, the mountain of San Cristobal, celebrated for the famous vein of Xacal, one of the richest and earliest exploited in the district, rises 450 meters above the city.

Jan 1, 1902

By T. B. Massalski, Horace Pops

Martensitic transformations were observed by optical metallography and electrical-resistivity measurements during cooling at cryogenic temperatures of the bcc pr-phase Au-Zn alloys. The com-position dependence of the MS, MF, AS , and AF temperatures have been determined. It is concluded that the martensitic platelets which grow mainly in the lengthwise direction and which are associated with a very small temperature hysteresis are "thermoelastic" martensite. In some cases the observed structure seems to have no definite crys-tallographic habit or consists of a mixture of- plates and broad transformed areas. THE majority of the bcc /3-phase alloys in systems of copper, silver, and gold with zinc and cadmium are unstable at low temperatures and undergo a transformation upon further cooling into another structure. A large number of such transformations are martensitic. The composition dependence of the Ms temperatures has been determined and reported for CU-~n,' Ag-Cd,' and AU-C~~ alloys. The 50 at. pct ordered Au-Zn p' alloy has been reported by Jan and pearson4 to transform martensitically at 58°K in connection with their study of the de Haas-van Alphen effect The p' phase in the Au-Zn system has the ordered CsC1-type structure. The phase field is shown in Fig. 1: it has the typical V shape which is characteristic of all copper-, silver-, and gold-based binary /3-phase alloys. There appears to be no a priori reason why the transformation should be limited to the equiatomic composition and the availability of a cryogenic stage for optical metallography5 has permitted studies down to the liquid-helium temperature of a series of alloys in this system. EXPERIMENTAL PROCEDURE Predetermined weights of 99.999 pct pure gold and zinc were melted and cast under a partial atmosphere of helium in sealed quartz capsules. Thorough mixing of the molten metals was achieved by vigorous shaking, followed by a rapid quench into a brine solution. All ingots were homogenized at 640°C for 4 days. The loss in weight was usually less than 0.04 wt pct and was assumed to be due to

Jan 1, 1965

Jan 1, 1955

By C. A. HEILANDG

THERE is a need for men well trained in geo- physical prospecting. Although the number of geophysicists required by the industry in the future cannot be expected to be very great, there will always be a demand for courses on the subject. A number of educational institutions are, therefore, interested in providing instruction in geophysical prospecting. Some institutions will be satisfied with courses in general geophysical prospecting designed to give the geologist fundamental concepts on the comparative merits of the methods and the interpretation of the results. Other institutions will want to give special instructions in theory, field procedure, and interpretation of any or all geophysical methods. In giving such special courses a number of problems will be faced, and it seems to me that such difficulties are easier to overcome in an engineering institution than in a university. A knowledge of basic engineering subjects, such as required of all students in an engineering school, seems to be the best foundation upon

Jan 1, 1930

By FLOYD T. TAYLOR

IN 1833, less than one hundred years ago, Michael Faraday discovered and stated the laws of electrolysis. His discovery formed the foundation of a new use of metals which has now reached a variety of application not ordinarily appreciated. Furthermore, things can be done with electro-deposited coatings which have thus far defied other methods. Some of the uses of electro-deposited coatings are interesting. The tonnage of metals already finding an outlet through such a channel is considerable. In general electro-deposits have two characteristics: ornament plus utility; utility plus ornament. Both these factors are usually found associated in electro- deposits. Ornament plus utility was probably the first use. For example, the silver-plating of tableware, having its real birth in Birmingham, England, about 1844. However, this same ornament plus utility retarded the development of electro-plating, because in the beginning, electro-plated articles were branded with the odium of imitation and shunned accordingly. The gold brick of the swindler may be an exception to this statement.

Jan 1, 1929

By W. W. Duecker

SULPHUR is a peculiar combination of a nuisance and a useful element. Most of the nonferrous metallic ores contain large amounts of it in the form of sulphides, which the metallurgist has wasted up the chimney, since the sulphur dioxide formed is generally too dilute to make recovery economical and practical. Iron ore does not contain much of the unwanted sulphur; in pig iron and coke it is most unwelcome. Gold metallurgists can get along nicely without sulphides in their cyanide plants and yet they find matte-a sulphur compound -an excellent collector for gold and silver in base-metal smelting. Also, sulphur appears in the non-metallics as in barite, gypsum, Glauber's salt, and celestite, all to useful purpose.

Jan 1, 1938

By E. V. Potter, H. C. Lukens

In general, during all electrowinning processes, large volumes of gas are liberated at the cathodes of the electrolytic cells. Most of this gas escapes from the electrolyte, but much of it may be absorbed or entrapped in the metal being plated. In many cases, this is not objectionable, but since it is liberated when the metal is heated, it is a potential source of trouble where the metal has to be heated or melted. Since this gas is principally hydrogen, in escaping from a melt it may cause minor explosions and scattering of the molten metal, while in other cases it has been reported to make the metal rise in the molds when cast. Therefore such metals would be more generally useful if all or most of the gas were removed before they were used. In an earlier investigation1 the gas content of electrolytic manganese was determined and methods found for removing most of it without detrimentally affecting the properties of the metal. In this paper results of a similar investigation on electrolytic chromium are presented. Apparatus The apparatus used in these investigations is essentially the same as that used in the manganese work1 and is shown in Fig I. It consists of sample chamber A, vacuum or pressure gauge B, volume gauge C, vacuum pump D, hydrogen container E, auxiliary gas chamber F, and furnace G. The pressure in the system is measured by the mercury manometer B. Changes in gas volume are measured by volume gauge C which is essentially another mercury manometer in which the volume of the mercury column is large and can be varied by raising or lowering the well H. In this apparatus the tube had a volume of 100 cc for a 60 cm length. Larger changes in gas volume can be accommodated by auxiliary containers attached to the system at F. The sample is heated by furnace G, the temperature of which is regulated within 5°C by an automatic controller. The only change in the apparatus was the sample container which was made smaller because of the chromium metal's containing more gas than the manganese metal and a smaller sample was used. Method The measurements were made as follows: The complete system when cold was evacuated and refilled with H2 until all the air was removed. It was then refilled with H2 to the desired pressure, as indicated on manometer B. The temperature was then raised to the desired value and as gas was either liberated from or absorbed by the sample, the height of well H was changed to alter the volume of the system so as to keep the pressure constant. In determining rates of liberation of gas, volume readings were taken at convenient tirne intervals depending on the rapidity with which the gas was liberated. In determining total volumes, the specimen was held at constant temperature and pressure until

Jan 1, 1949

By R. A., Pallanch

SO many variations of lead-zinc ores occur in nature that it is impossible to state any rules that will apply to the concentration of ores of this type. Some have lead and zinc in approximately equal amounts; others may have pre- dominant amounts of one or the other metal. There are gradations from all sulfide to completely oxidized minerals. Some such ores carry little pyrite, others contain much more pyrite than they do lead and zinc combined. The behavior of ores in flotation is largely a function of their lead-zinc ratios. their content of pyrite or pyrhotite, the nature of existing soluble salt conditions, the character of the gangue constituents: and the speed with which the minerals float. For the purposes of this paper only those lead-zinc ores handled commonly in present-day flotation practice will be considered. These are practically all-sulfide ores with relatively minor degrees of sulphatization or oxidation.

Jan 1, 1936

By S. H. Lorain, Norman L. Wimmler, S. Ricker, P. E. Oscarson, H. G. Iverson

This paper has been prepared with the principal objective of recording the results of the Bureau of Mines exploration of five major clay deposits in the Western Region. It is based mainly on data contained in unpublished Bureau of Mines reports. Acknowledgment is made to the Federal Geological Survey for its cooperative work with the Bureau of Mines, to the various State geological and mining departments, and other State and local agencies. Clay Exploration by the Bureau of Mines Much has been written and published on clays and clay deposits relating to their refractory, ceramic, and other qualities but such literature is lacking in analyses of the available alumina content of the clays and provides little indication of their possibilities as a source of alumina. With this new objective in view, a great many of the known clay deposits were reexamined and new ones discovered. The Bureau of Mines made preliminary examination of numerous areas in the western United States. Five of those most favorably indicated were systematically drilled, and in each a large amount of high-alumina clay has been found. These five major projects are Molalla and Hobart Butte, in western Oregon; Cowlitz-Castle Rock, in southwestern Washington; Ione, in California; and the Olson-Troy area in Idaho (Fig. I). Preliminary scout drilling was done in the Stockton deposit at Coeur d'Alene, Idaho; the White ware deposit near Lewis-town, Mont.; and 13 areas in the Spokane or eastern Washington region, where the most favorably indicated area, known as the Excelsior, is now being drilled more systematically. Preliminary drilling was undertaken in numerous areas adjacent to the major deposits and others more remote. As a result, large additional clay possibilities were found. The Clay Deposits The clay deposits under consideration are of the sedimentary or transported types, parts of which have been altered further by the agencies of weathering, ground water, or hydrothermal action. There are extensive deposits of residual clays in northern Idaho and in eastern Washington, but they have been found to be low in the available alumina and to contain much free quartz, mica, and unaltered feldspar. To be of value, they must first be subjected to beneficiation to remove these gangue minerals. The sedimentary clays have been derived largely from the decomposition, erosion, and transportation of granites, gneisses, schists, and basalts. At Molalla, some

Jan 1, 1948

By Norman L. Wimmler, H. G. Iverson, S. Ricker, P. E. Oscarson, S. H. Lorain

This paper has been prepared with the principal objective of recording the results of the Bureau of Mines exploration of five major clay deposits in the Western Region. It is based mainly on data contained in unpublished Bureau of Mines reports. Acknowledgment is made to the Federal Geological Survey for its cooperative work with the Bureau of Mines, to the various State geological and mining departments, and other State and local agencies. Clay Exploration by the Bureau of Mines Much has been written and published on clays and clay deposits relating to their refractory, ceramic, and other qualities but such literature is lacking in analyses of the available alumina content of the clays and provides little indication of their possibilities as a source of alumina. With this new objective in view, a great many of the known clay deposits were reexamined and new ones discovered. The Bureau of Mines made preliminary examination of numerous areas in the western United States. Five of those most favorably indicated were systematically drilled, and in each a large amount of high-alumina clay has been found. These five major projects are Molalla and Hobart Butte, in western Oregon; Cowlitz-Castle Rock, in southwestern Washington; Ione, in California; and the Olson-Troy area in Idaho (Fig. I). Preliminary scout drilling was done in the Stockton deposit at Coeur d'Alene, Idaho; the White ware deposit near Lewis-town, Mont.; and 13 areas in the Spokane or eastern Washington region, where the most favorably indicated area, known as the Excelsior, is now being drilled more systematically. Preliminary drilling was undertaken in numerous areas adjacent to the major deposits and others more remote. As a result, large additional clay possibilities were found. The Clay Deposits The clay deposits under consideration are of the sedimentary or transported types, parts of which have been altered further by the agencies of weathering, ground water, or hydrothermal action. There are extensive deposits of residual clays in northern Idaho and in eastern Washington, but they have been found to be low in the available alumina and to contain much free quartz, mica, and unaltered feldspar. To be of value, they must first be subjected to beneficiation to remove these gangue minerals. The sedimentary clays have been derived largely from the decomposition, erosion, and transportation of granites, gneisses, schists, and basalts. At Molalla, some

Jan 1, 1948

By W. H. Bassett

W H. BASSETT was elected first vice-president at . the executive session of the new Board on Tues- day afternoon. Karl Eilers, H. Foster Bain, Thomas T. Read, and H. A. Maloney were respectively re-elected as treasurer, secretary, assistant secretary and assistant treasurer. The new Executive Committee will consist of W. H. Bassett, Chairman, and Richard Peters, Jr., H. C. Bellinger, E. De Golyer, Edgar Rickard. The Finance Committee will be J. V. W. Reynders, Chair- man, Henry Krumb and H. G. Moulton. George D. Barron was reappointed Chairman of the Admissions Committee, and F. Julius Fohs put in charge of the Papers and Publications Committee.

Jan 1, 1929

By Walter Crafts

STRUCTURAL steels containing chromium have become widely used in the last 20 years. In the earlier part of this period the major applications were in chromium-molybdenum aircraft tubing and similar special high-strength steels. During the past 10 years there has been a notable expansion in the use of chromium-bearing steel for structural purposes when welding was utilized for fabrication. The chromium-bearing steels introduced by Saklatwalla1 (chromium-copper), Kinzel2 (chromium-manganese-silicon), and Schultz3 (chromium-copper) are being extensively used at the present time.

Jan 1, 1939

By C. W. Dunham

DESIGN of the structures for the Morenci Reduction Works involved many interesting problems. Naturally, the chief purpose of these structures is to house and support the equipment and other things necessary for or incidental to the conduct of production. hence most of the features of the design were developed to suit these particular conditions; however, several are so generally applicable as to warrant description.

Jan 1, 1942

By James A. Soles

Concrete is a complex, multicomponent mass whose stability is dependent on three principal variables: quality of the mix, its composition, and environment of the site. The aggregate is only one component, but its constituent minerals may react in unfavorable regimes and, given sufficient time, destroy the concrete. Therefore, besides ensuring that a concrete will meet the strength requirements of a structure, the concrete engineer must be confident that the mortar and aggregates will resist destructive processes. This paper reviews the principal causes and effects of aggregate instability, notes reactions of certain phases, and suggests precautionary measures that can be taken to extend the useful life of concrete structures.

Jan 1, 1984

Elected Died 1895 *ABBOTT, AI ATTHUR 1908 1882 *ABBOTT, ARTHUR V 1906 1905 * ABE, MASAYOSHI 1909 1903 * ADAMS, CHARLES C. 1905 1906 * ADAMS, JOHN C. 1913 1905 * ADAMS, WILLAMS 1909 1903 * ADAMS, W. EDWARDS 1910 1884 *ADDY, MATTHEW 1896 1906 * AFFLECK, WILLIAM A. 1911 1889 * AKERS, WILLIAMS 1906 1905 * ALABASTER, RUPPERT C. 1911 1899 * ALBERGER, LOUIS R. 1911 1894 *ALLEN R B 1896 1905 * ALLEN, R. SCOTT 1906 1874 * AMIOT, H. 1892 1886 *AMSLER, CARL 1894 1898 ** ANFERSON, JOHN w. 1905 1895 *ÅNGSTROM, CARL 1901 1887 * ARCHBALD, JAMES 1910 1900 * ARLETT, GEORGE H 1906 1895 *ARMSTRONG, JOHN F 1898 1882 *ARNOLDS, HUGO 1886 1875 *ASHBURNER, CHARLES A 1889 1872 *ASIIBURNER, WILLIAM 1887 1883 *ATKINS, C M , JR 1885 1905 * AUSTEN, PETER T 1907

Jan 1, 1917