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By D. R. de Fontaine

By computing the values of the resolved shear stress for a great many orientations of the tensile axis on all 12 (111) <110> slip systems, Taylor and Elam&apos; were able to map out a stereogram of slip systems, given here, Fig. 1, in Diehl&apos;s notation (see, for example Hauser and Jackson&apos;). The purpose of the present note is to derive such a stereogram by mathematical reasoning and to give a simple method of defining the system with highest resolved shear stress for any direction of the tensile axis, thereby eliminating tedious computation of the Schmid factor. Let the tensile axis, of direction cosines [xyz], make the angles 0 and relative to the slip plane normal [HKL] and the slip direction [hkl] respectively. Fig. 2 shows a simple cubic cell whose edges define a Cartesian coordinate system. Let A be a unit vector of origin 0 supported by the tensile axis. Its end point [xyz] then lies on a sphere of unit radius, on the positive hemisphere of which the planes z = 0, x = y, y = z limit the so called primitive triangle of a standard [loo] stereographic projection. For any point of this triangle, the following hold: 0«2 «y *sx « 1 [l] Now, for given [xpz], the most highly stressed system will be the one for which the following expression of the Schmid factor has the largest possible value: (HKL) belonging to the form (111) and [hkl] to the form <110>, the denominator on the right hand side of Eq. [2] is equal to 1.fi.a. The unknowns H, ... h, . . . can now be determined by correctly distributing +1 and -1 to H, K, L, and +1, -1,O to h,k, 1 giving the numerator of Eq. [2] its greatest positive value (the angles 0 and cpare chosen acute) subject to the condition: Hh+Kk+Ll = 0 [3] since the slip direction must lie in the slip plane. Condition [3] can be satisfied only by having one of its terms vanish and the other two equal to +1 and -1. Taking the case of the tensile axis lying in the primitive triangle, x2y, z and therefore Hh will be chosen equal to +1 with H = h = +1 in order to retain a maximum of + signs. There remain two alternatives: either 1 = 0 or k = 0. 1) take 2 = 0 Then Kk = -1 and the numerator of [2] becomes: Retaining a maximum of + signs gives L = k = +1 and becomes: 2) take k = 0 Then L1 = -1and, likewise, the numerator of [2] becomes: xz - z2 + xy + yz [5] But the difference [5] - [4] can be written: (y - z)(x+y +z) [6] positive or zero by virtue of [I]. If [6] is positive (y > z), then the largest possible value for the numerator of [2] for any xyz inside the primitive triangle is given by [5], i.e., for: That is to say, the active slip system corresponding to an orientat:~on of the tensile axis inside the primitive triangle is:

Jan 1, 1962

By C. G. Goetzel

E. V. Crane.*—I want to ask Dr. Goetzel concerning the control of atmosphere in heating and pressing. Was the heating and pressing done in the die, or were the two kept separate there? C. G. Goetzel.—The setup used for this investigation implied heating the die to the temperature at which the work was to proceed, introducing a preformed compact into the hot die. The atmosphere was supplied through an annular chamber from which it passed through two holes into the die cavity. E. V. CRane.—The compact was not preheated? C. G. Goetzel.—The compact was not preheated. Tee Chairman.—In the course of recent studies on the effect of time of heating upon the tensile strength and hardness, I have observed that there is often a maximum in tensile strength and hardness reached before complete homogenization has been attained. The magnitude of each mechanical Property changes rapidly with time in the early stages of sintering, the more so as temperature increases. For these reasons it seems that the comparison of values obtained by heating for the same time at a series of temperatures may be deceptive. Not only may those heated at higher temperatures give higher tensile readings, but the reverse may be true if the maximum in the tensile strength versus time curve has been passed. A better basis for comparison would be that of equal degree of diffusion. C&apos; " Goetzel.—Thank you, Professor Rhines, for this interesting contribution. I would like to add here that I have noticed a similar effect with straight copper. There is, of course, the possibility that this maximum in hardness and tensile strength may be caused by work-hardening.

Jan 1, 1945

By H. H. Uhlig

In our study of the mechanism of and the prevention of corrosion in stainless steels, it was considered of fundamental importance to obtain knowledge of the surface structure of such alloys. If corrosion resistance is due to a self-healing oxide layer, which like a paint film protects the underlying metal, it would be obviously relevant were the effort made to make the film less permeable and more adherent; for example, the surface might be expected to respond to an anodizing process, which is found successful in increasing the film thickness and corrosion resistance of aluminum. However, if passivity and corrosion resistance of stainless steels are due to another cause, the attack of the problem would follow another path. One of the most effective techniques for studying passivity and corrosion tendency is the measurement of the electrochemical potential. Not only can one determine by potential measurements whether a metal is active or passive, but also one can determine the degree of passivity and rate of transformation of passivity with time. Chemical media that build up or destroy passivity when in contact with the steel can also be classified by potential measurements. Something can be learned, too, of the effect of alloy additions such as molybdenum to 18-8, known to decrease corrosion of the alloy in chloride solutions. A study of alloys in previous investigations has sometimes included data on the electrochemical potentials. Tammann and Sotterl measured the electrochenlical potentials of alloys of iron-molybdenum and iron-chromium and reperted the critical concentration of molybdenum or chromium at which passivity initiates. Strauss2 made similar measurements for the iron-chromium system. The electrochemical potential3 has also been used to indicate carbide precipitated 18-8. In 18-8, heat-treated to precipitate carbide, active metal exists at the region of the grain boundaries, contrasted with passive metal within the grains, the active metal accounting for a resultant active potential. Several

Jan 1, 1940

By H. H. Uhlig

In our study of the mechanism of and the prevention of corrosion in stainless steels, it was considered of fundamental importance to obtain knowledge of the surface structure of such alloys. If corrosion resistance is due to a self-healing oxide layer, which like a paint film protects the underlying metal, it would be obviously relevant were the effort made to make the film less permeable and more adherent; for example, the surface might be expected to respond to an anodizing process, which is found successful in increasing the film thickness and corrosion resistance of aluminum. However, if passivity and corrosion resistance of stainless steels are due to another cause, the attack of the problem would follow another path. One of the most effective techniques for studying passivity and corrosion tendency is the measurement of the electrochemical potential. Not only can one determine by potential measurements whether a metal is active or passive, but also one can determine the degree of passivity and rate of transformation of passivity with time. Chemical media that build up or destroy passivity when in contact with the steel can also be classified by potential measurements. Something can be learned, too, of the effect of alloy additions such as molybdenum to 18-8, known to decrease corrosion of the alloy in chloride solutions. A study of alloys in previous investigations has sometimes included data on the electrochemical potentials. Tammann and Sotterl measured the electrochenlical potentials of alloys of iron-molybdenum and iron-chromium and reperted the critical concentration of molybdenum or chromium at which passivity initiates. Strauss2 made similar measurements for the iron-chromium system. The electrochemical potential3 has also been used to indicate carbide precipitated 18-8. In 18-8, heat-treated to precipitate carbide, active metal exists at the region of the grain boundaries, contrasted with passive metal within the grains, the active metal accounting for a resultant active potential. Several

Jan 1, 1940

R. H. THURSTON, Cornell University, Ithaca, N. Y. (communication to the Secretary): The " tri-axial diagram" was, I think, first employed by me in the work of the " U. 8. Board Appointed to Test Iron, Steel and Other Metals." A model was exhibited to the American Association for the Advancement of Science, and the diagram was first published, and the model described, in a paper presented to the same society at its Nashville meeting in 1877." The problem then presented to its inventor was to find a method of planning a research involving proportions of ternary compositions in such manner that, a limited number of such compositions being tested, the results should give the law of variation in the physical properties of all possible combinations of the three elements, and the actual numerical values of such as were important to the investigator. The investigation of the binary alloys, copper and tin, copper and zinc, and tin and zinc, had been completed and satisfactorily discussed, employing the usual bi-axial diagram, of which the ordinates represented the one, and the abscissæ the other, of the characteristic properties to be studied, the composition being commonly indicated by the abscissæ. In these cases it was easy to ascertain, by the study of a limited number of compounds, the law of variation in strength, ductility, etc., with composition; but, for a long time, the ternary alloys were not attacked, because no simple and satisfactory method presented itself of securing results significant for the whole field by the investigation of a comparatively small number of alloys. The tri-axial diagram was finally hit upon as a means of representing and interpreting results, and researches were at once begun, and in due time satisfactorily completed.

Jan 1, 1899

By L. Messulam, A. S. Appleton

Iwo major studies of the Fe-Cr-C system are available in the literature. The earlier one of Kinzel and crafts&apos; forms the basis for the data most commonly quoted in works of reference (e.g., Metnls HandDook) though the later work of Bungardt el a1.&apos; is more extensive and amenable to analysis in terms of isothermal sections and so forth. However it is evident from examination of either of these studies that the delination of phase boundaries on the basis of the data obtained can only be very approximate. Indeed in several instances the data are so inconclusive that this delineation is a matter of opinion. This note is to report an analysis of experimentally determined carbon activity data in this system, which, originally intended as a means of checking the self-consistency of the data for a number of alloys, enables some conclusions to be drawn concerning the 10503C isothermal section of the iron-rich corner of the system as deducible from the data of Bungardt

Jan 1, 1967

Article IX of the Bylaws constitutes the basic instructions to the Nominating Committee The first duty of the Nominating Committee is to select a candidate for Director and President-elect It is desirable that the successive Presidents from year to year be men of differing professional interests so selected that over a period of years each major group in the Institute will be represented in the Presidency a number of times bearing some reasonable relationship to the numerical strength of that group in the Institute In Section 2 of Article IX it is stated that "a sufficient number of Directors be selected on the basis of geographical districts so that each district will have at least one representative" These districts, as now established, are shown in the accompanying map There are ten districts including the New York metropolitan district Each of these districts is entitled to one Director, except the metropolitan district which is entitled to six Each year each district, the term of whose officially recommended Director expires, shall suggest a candidate and if desired an alternate candidate to the Nominating Committee to fill the vacancy If a candidate and an alternate are suggested they should preferably have different Divisional or Branch affiliations The Chairmen of the Sections In the district shall constitute a committee to select the candidate or candidates The Sections shall rotate the chairmanship, as shown in the Appendix to this instruction It is desirable that in filling a quota vacancy in any district, the selection be made from the name or names suggested by the district

Jan 1, 1952

Geological and Natural History Survey of Wisconsin, The University of Wisconsin, Madison, Wis - E. F Bean, State Geologist. A complete list of publications of this Survey will be sent upon request Only a portion of the Bulletins and Maps fall within the scope of this directory, and most of them are available They are: Bulletin 4, Building and ornamental stones of Wisconsin (1898), $2 50, 6, Preliminary report on the copper-bearing rocks of Douglas County, and parts of Washburn and Bayfield counties (1901), 50 cents, 7, The clays and clay industries of Wisconsin (pt 1) (1901), 50 cents; 14, Report on lead and zinc deposits of Wisconsin (the report is out of print but the 18 maps which accompanied it can still be had) (1906), 20 cents (a series of six maps, supplementary to these (1909), may be had for 6 cents), 15, The clays of Wisconsin and their uses (1906), 50 cents; 16, The geology of north-central Wisconsin (1907), $2, 17, The abandoned shore lines of eastern Wisconsin (1907), 50 cents, 19, Zinc and lead deposits of the Upper Mississippi Valley (1907), 25 cents; 34, The limestone road materials of Wisconsin (1914), 50 cents, 35, Underground and surface water supplies of Wisconsin (1915), $150, 36, The physiography of Wisconsin (new edition now in press) (1916), $125, 41, A study of methods of mine assessments and valuation (1914), 50 cents; 44, Mineral land classification in parts of northwestern Wisconsin (1915), $5, 45, The peat resources of Wisconsin (1915), 50 cents, 46, Mineral

Jan 1, 1933

Reginald S. Dean (Manganese Extraction by Carbamate Solutions and the Chemistry of New Manganese-Ammonia Complexes, P. 55) was born in Rolla, Mo. and attended the Missouri School of Mines. Mr. Dean has worked as metallurgist with Western Electric Co. from 1920 to 1929 and with U. S. Bureau of Mines from 1929 to 1946 as chief metallurgist and assistant director, and has been a metallurgical consultant in Washington, D. C. since 1946. An AIME member, Mr. Dean has presented at least 50 papers before the society. Mr. Dean is a member of American Society of Metals, American Chemical Society and Electrochemical Society. C. O. Dale (Illinois Operations of the Eagle Picher Mining and Smelting Co., co-author with W. J. Rundel, P. 72) was born in Twin Bridges, Mont. and attended Montana School of Mines and received his B.S. in mining engineering in 1944. Mr. Dale was with U. S. Navy Air Corps. as an electronics technician and worked as an engineer with C. O. Dale & Sons, Anaconda Copper Mining Co. and with Eagle Picher Mining & Smelting Co. At present he is Wisconsin manager of Eagle Picher Mining & Smelting Co. The application of machinery to mining is of special interest to Mr. Dale. A member of AIME, Mr. Dale is on the Room and Pillar or Stope and Pillar Committee of Mining Subdivision for 1951 to 1952. Mr. Dale is a member of Montana Society of Engineers and Lions Club. Golfing, fishing and wood working are his hobbies.

Jan 1, 1952

The following is an incomplete list of members and guests who called at Institute headquarters between Nov. 10 and Dec. 10, 1917. Harlan H. Bradt, Duluth, Minn. Lt. Geo. H. Morgan. Albert Burch, San Francisco, Cal. F. W. Osborn, Ajo, Ariz. J. A. Daniel, Institute of Mining & Metal- J. C. Ray, 2d Lt., 0. M. C., N. A. lurgy, London. A. E. Ring, Creede, Colo. Martin Fishback, Benson, Ariz. Geo. B. Rodgers, Dobbs Ferry, N. Y. E. L. Foucar, San Francisco, Cal. Forest Rutherford, Pueblo, Colo. I. A. L. Henderson, Institute of Mining & J. G. Scrugham, Reno, Nev. Metallurgy, London. A. F. Shurick, Forest Hills, L. I., N. Y. Jerome A. Hilbert, Santa Monica, Cal. Arthur C. Spencer, Washington, D. C. B. B. Hood, Chrome, N. J. Robert C. Sticht, Mt. Lyell, Tasmania. J. C. Hoyt, Jerome, Ariz. A. Perry Thompson, San Francisco, Cal. A. F. Kennedy, Duluth, Minn. J. B. Tyrrell, Toronto, Canada. Paul S. King, Wilmington, Del. Thor. Warner, Phoenix, Ariz. Alfred C. Levis, Golden, Colo. S. F. Wellman, Cleveland, 0. A. F. Lucas, Washington, D. C. Gardner F. Williams, San Francisco, Cal. B. E. McKechnie, Sharon, Pa. W. G. Woolf, Salt Lake City, Utah.&apos; A. N. Mackay, Barranquilla, Colombia. C. W. Merrill, San Francisco, Cal. P. G. Beckett expects to be located in New York for some time, and may be addressed care of the Phelps, Dodge Corporation at 99 John Street. Corey C. Brayton and E. R. Richards have temporarily closed their San Francisco offices in order to give more time to their operations at Midvale, Utah.

Jan 1, 1918

By Walter Renton Ingalls

The ores of zinc which are important as sources of that metal are of two classes, viz., the sulphide and the oxidized. The latter includes six varieties: zincite (the red oxide) and franklinite (the oxide of zinc, iron, and manganese), which are found abundantly only in New Jersey; and the hydrous and anhydrous carbonates, the hydrous and anhydrous silicates, which are of widespread occurrence. The hydrous carbonate is known mineralogically as hydrozincite, zinconise, or zinc-bloom; the anhydrous silicate is recognized as willemite. With respect to the anhydrous carbonate and the hydrous silicate, however, there is a confusion of name which is of old standing. Attempts to clear it away were long ago made by the mineralogists with the result that there is now a more or less national uniformity of nomenclature; but there is still an international disagreement, sometimes very perplexing and always leading to inexactness in expression, which may be considered an adequate excuse for this return to a time-worn subject. The name calamine, together with Galmei of the Germans, is commonly supposed to be derived from xadµela, which was used by the Greeks to designate the peculiar kind of ore employed with copper in their brass-making, and also the accretions which formed in the brass-founder&apos;s furnaces. Agricola, however, says that it is from calamm, a reed, in allusion to the appearance of the material, cadmia fornacum, which collected 011 the furnace-walls. But whatever the derivation of the word, it was used until within one hundred years to include all the oxidized

Jan 1, 1896

By Walter McDermott

THIS machine is an improvement on the well-known endless traveling belt used for dressing slimes in many mills ; the chief point of difference, and constituting the essential advantage of the present over the old form, is the application to the machine of a secondary agitating or shaking motion, in addition to the ordinary progressive motion of-the belt. In the machine as heretofore made, the inclined belt or apron moved slowly up against a thin stream of water and ore, depositing the concentrations carried over in a tank placed below, through which the belt travelled, of course, in a reversed position. By reference to the accompanying drawings, it will be seen that in this main principle the new modification does not differ materially; but the means by which it is carried out are essentially different. The machine consists of a substantial frame of mood, F, Figs. 41, 42, and 43, within which hang the shaking frame and rollers, B B, A, Endless apron ; B, Apron frame and rollers ; C, Driving drum ; D, pulleys; El Shaft and connecting rods; F, Wooden frame; G, Shaft of regulating Pulley ; H, Yokes. supporting the upper half of the travelling apron, A, which passes below around the driving drum, C, in the water-tank, J. On leaving the water-tank, the belt passes over the guiding and tightener pulley, G. The ends of the shaking-frame, B, are provided with iron yokes, H H, bored to admit the shafts of the end rollers, and carrying a lug, by which attachment is made to the connecting rods,

Jan 1, 1875

By L. O. Howard

THE practice of using acid-lined converters at the plant of the Old Dominion Copper Mining & Smelting Co. was discontinued early in January, 1913, and they were replaced by basic-lined converters. The new equipment consists of one electrically operated 12-ft. upright converter stand and two basic-lined shells for same. These shells are provided with twenty-four 1 1/4-in. tuyères. The mouths are 5 ft. in diameter. Owing to the fact that there is no bedding system or other large storage capacity between the mine and the smelter, the furnaces must handle as fast as produced ore and concentrates, which may vary considerably from day to day, both in tonnage and copper content. Consequently the converter is often crowded to its utmost capacity by the frequent fluctuations in the daily matte supply. From the foregoing, it will be seen that in no way can the converter be favored by running light charges or by transferring to it from other stands in operation. Neither can it regularly be allowed to cool between blows, and only occasionally can it be run at as low a temperature as might be wished. No copper precipitate or other foreign material high in copper is available to help out the tonnage. Repairs and alterations or the removal of defective tuyères must wait until such time as a slight falling off in the matte supply-allows the converting operations to ease up. These variable conditions all combine to interfere with the systematic operating of the converter.

Jan 7, 1914

By John V. Beall

Probably the only hotel in the world with near 100% occupancy at all times is the modern Hotel Indonesia in Djakarta. However, there is little gaiety among the scores of business men who occupy the hotel because they fret as days grow into weeks in seemingly interminable negotiations with government officials. As one man put it, "time is a dimension that they [Indonesians] have never grasped." But the visitors still come in droves to investigate business opportunities in this sprawling nation of tropical islands which is, with 120 million people, the fifth largest nation in the world. Approximately $300 million is being spent each year in Indonesia by foreign companies and governments. Aid grants from the latter are derived about one third from the United States, one third from Japan and the remainder from many nations. Djakarta is a far cry from pleasant colonial Batavia, as the city was called under the Dutch. The orderly colony of prewar days was managed as an agricultural and trading dependency of Holland. The Dutch did little about educating the people. The islands were controlled by the Japanese during World War II and afterwards there was a war for independence--which was attained in 1949. In the ensuing years, President Sukarno devastated the economy by squandering money on a gigantic scale. A Communist-attempted coup in 1965 resulted in a military takeover and the extermination of Communists. The new government under Suharto, which took over all power in March 1966, found itself in a situation where bare survival was the first consideration.

Jan 1, 1970

By Reger, B. David

FOR many years, the belief that the so-called "Clinton" sand of Ohio might produce. oil and gas, if it could be reached, has been prevalent in West Virginia. To test this theory, many hundreds of thousands of dollars have been spent and several extremely deep wells, including the deepest boring of the world, have been sunk at various points. With the exception of one well now completed through the sand and the possible exception of another still in progress, all of these wells failed to reach the goal, either through failure of funds or through drilling accidents. REVIEW OF DEEP DRILLING The subject of deep-sand oil and gas in West Virginia has already been discussed by the author1 and by White.2 In these papers, it was shown that the Upper and. Middle Devonian shales, lying between the Berea oil sand (basal Mississippian) and the Oriskany sandstone (Lower Devonian), thicken steadily from eastern Ohio across northern West Virginia and Pennsylvania; but it was stated that the same rate of thickening did not occur in that part of West Virginia south of the Great Kanawha River and in the adjoining portion of Kentucky. In spite of this great eastward thickening, the fact that both the Oriskany and "Clinton" sands, the latter of which is equivalent to the White Medina of New York, exist in great thickness all along the Appalachian Mountains farther east, was held as proof of their probable presence in the deep Appalachian basin.

Jan 3, 1925

Works Manager or General Superintendent.-Technical graduate, for position with a company whose works consist of a large machine shop and foundry. This company manufactures well-known power plant equipment. Location, Pennsylvania. Salary, $5000-$8000 per year. R-871. Motion Study Engineer with extensive experience in shop operation and motion study. Must have sufficient technical experience to recognize inefficiency and waste in plant. Salary, $175-$200 per month. Location, New Jersey. R-876. Metallurgical Engineer.-Technical graduate with at least 2 or 3 years&apos; practical experience in the operation of zinc smelters. Duties will be to take charge, under the guidance of -the superintendent of the smelter, of the operating end of the furnaces, and the roasting kilns, as well as the mix room and ore crusher. Man desired should not be over 30 years of age and should be progressive and able to handle men. Salary, $250 per month. Location, Oklahoma. R-877. Private Secretary to Vice-president in charge of development department and laboratories of large manufacturing plant; must be technical man of good personality, and A-1 in every respect, as position is an important and responsible one. Location, Ohio. R-896. Sales. Engineer familiar with his local territory, particularly with the fanning trade. Should have had at least 2 years&apos; experience in selling tractors; and in any event, must have had at least 5 years&apos; experience in selling machinery. High grade, energetic, and capable; man who is not satisfied with less than $3000 per year and who can earn up to $7000. Location, Iowa. R-897.

Jan 8, 1919

By Haim Chiswik

IN recent years considerable attention has been devoted to the devel-opment of new commercial uses for silver, chiefly because of lowered prices and large stocks of the metal. This has led to increased interest in the phase diagrams of silver alloys. The silver-lead diagram is reported&apos; to be of the simple eutectic type, but no measurements of the solubility of lead in silver have been made. The solubility of silver in lead has been estimated2 from diffusion experiments and resistance measurements to vary with temperature from 0.09 to 0.18 atomic per cent (0.05 to 0.10 weight per cent). Silver-rich silver-lead alloys have recently been recommended as high-strength bearing metals.3 The silver-bismuth diagram is similar.&apos; The solubility of bismuth in silver has been estimated to be about 5.5 weight per cent on the basis of X-ray work.4 Matthiessen5 found a solubility of silver in bismuth from 0.25 to 0.50 per cent by conductivity measurements. Silver and thallium form the same type of diagram,1 with no data on their mutual miscibilities. We have studied the first two of these diagrams by X-ray methods, verifying their main features and determining the solubilities of lead and bismuth in silver at several temperatures. We also determined the solubility of thallium in silver at one temperature. The solubilities of silver in lead and in bismuth were found to be too low to be detectable.

Jan 1, 1940

By John J. Borkert, Carl E. Gerity

In situ mining offers a new and proven method of exploiting sedimentary uranium deposits. The feasibility and economic evaluation of exploiting a uranium reserve by either open pit or underground mining should also include a similar study for in situ mining. This report compares the economics of mining several hypothetical uranium deposits at various depths, grades and reserve sizes by open pit and in situ mining. The evaluation process evolved establishing, where possible, common geological and logistical parameters to both methods of mining. The various assumptions that are unique to either open pit or in situ mining were also drafted, where possible, as equal and common functions to be used in each economic evaluation of the reserve models. After the various parameters were defined, they were programmed to an economic analysis of the various hypothetical uranium deposits by the selected mining method. From the vast array of cost evaluations, total capital and operating cost per pound U308 produced, DCF-ROI, and total net profits before State and Federal taxes were selected as the most meaningful results to compare. From the various geologic parameters used, it was determined that the economic viability of a mining venture is most sensitive to a depth-grade thickness ratio. The three selected evaluation products were plotted against the various depth-grade thickness ratios of the hypothetical uranium deposits. The results of the economic cost analyses show in situ mining generally to be a better method to maximize total net profits and to maximize return on investment.

Jan 1, 1979

By Clemens Jones

An interesting paper by J. E. Merion and Edward Hart, in Volume I., No. 2, of the Journal of Analytical Chemistry, on the Decomposition of Blast-Furnace Cinder by Acid, describes a plan of sampling the cinder by means of a previously-heated iron bar thrust into the cinder car or into the cinder at the notch, and then allowed to cool, thus chilling the cinder which adheres to the bar, and rendering it decomposable by hydrochloric acid, of 1.12 sp. gr. A short series of results is given, from which the deduction follows that blast-furnace cinder " is decomposed perfectly when chilled." Where many silica determinations are to be made, this method, if reliable, would effect notable economy of time and reagents. The conversion of insoluble silicates by fusion with an alkaline carbonate, together with the subsequent solution, evaporation, drying, etc., is destined to remain the standard method. But all fusionmethods are time-consuming and expensive. Chilling appears to render the supplementary method available for all practical purposes, in the determination of silica in cinder. But, with a view of securing more evidence on the subject, and in view of the fact that uniform results were not obtained by employing this method, it was decided to test the method in the laboratory of the Thomas Iron Company where a large number of silica determinations are made. The experience met with may not be devoid of value, both theoretical and practical. Mr. Iles&apos;s paper, in the Chemical News, Volume L., 1881, doubtless suggested to several chemists, connected with iron metallurgical

Jan 1, 1888

By Thomas A. Wright

No symposium on die casting could be complete without consideration of the methods of formula and impurity control. No consideration of control would be complete without discussion of that new tool of the analytical chemist and inspector, the quartz spectrograph. Just as there is an increased appreciation of the possible applications of the die-casting process and of die castings, so too is there, slowly but surely, of the spectrograph. At present the role of the instrument might well be compared with that of brass or magnesium die castings. Neither is as widely understood or known as they will be. Product specifications are increasing and are getting more explicit and often more rigid. The designer, metallurgist and production engineer or superintendent will be forced to depend more and more on the chemical laboratory. Sampling, as well as analyses, testing and inspection problems will grow. The chemical laboratory must meet its increased responsibility and use of the spectrograph will become more common. Advantages of increased precision, greater speed, lessened labor and often lower costs cannot be ignored. It will be the purpose of this paper in part to outline the respective fields of chemical and spectrographic analyses and to indicate where one may overlap the other and in part to indicate certain possible sources of contamination of zinc-base die-cast alloys in particular. COMPOSITION Aluminum.-Aluminum die castings are expected to conform to the specifications of the American Society for Testing Materials1† and the Society of Automotive Engineers2. The A.S.T.M. has recognized seven

Jan 1, 1935