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By E. V. Crane

A TREMENDOUS volume of the metal rolled annually into sheets, strips and coil stock finds its way to a host of stamping and manufacturing plants which are the quantity production units of the country. Considerable in volume, too, are the rolled and extruded rods which go into forging and manufacturing plants for conversion into the same general line: those widely sold metallic necessities and luxuries of the household, the office, transportation, farming and building construction. Yet, in spite of its age and its importance, the stamping trade has been doing its "engineering" largely by trial and error. Its distinctive method is shearing out and plastically working metal to finished shape in a few quick strokes with high loads and expensive tools which are warranted only by large quantities to be produced. The principal operations have many features in common with rolling and wire-drawing methods. Combinations of stresses are different, however, and details of operations are infinite in variety. An engineering study of the subject begins with stress analysis, but must go back to metallurgy for its foundation. A grouping of pressed-metal working operations according to whether the metal is (1) sheared, (2) bent, (3) drawn or (4) squeezed has proved useful. All of these groups include instances of both hot and cold operations. For discussions of metal working properties, the division between hot and cold working is taken as the recrystallization range of temperature. This, of course, brings tin, lead and often zinc into the hot-work range at or near room temperature. The outstanding hot-working press field is in forging: particularly of brass; all of which is included in the squeezing group.

Jan 1, 1931

ALBERT J. PHILLIPS, Chairman E. H. Dix, JR., Past-chairman R. H. LEACH, Vice-chairman R. F. MEHL, Vice-chairman W. M. COME, Treasurer LOUIS JORDAN, Secretary 29 West 39th St., New York, N. Y.

Jan 1, 1937

By Francis L. Bosqui

The following paper embodies a report which I made on the filter-press treatment of slimes at the Liberty Bell mine, Telluride, Colo. At the time this report was submitted, the management deemed it wiser to defer the installation of so costly a plant as the one required, in the hope that some of the many investigators in the field might soon evolve a cheaper and more perfect method of slimes-treatment, and one better suited to the conditions at Telluride. The Liberty Bell ore consists essentially of quartz and clay, with iron pyrites disseminated through the quartz in very fine particles. There is considerable iron and manganese stain in some of the ore, the latter especially in the clays, which are sometimes quite black. Occasionally particles of galena, zincblende, gray copper and a few other minerals are seen, but they are comparatively rare, and not in sufficient quantity to affect considerations of treatment. Free gold is occasionally seen in the quartz, and one or two instances of mire silver have been observed. The milling-plant consists of an 80-stamp amalgamating mill which crushes through 20-mesh screens; 20 Wilfley concentrating tables, taking out, in iron sulphides, about 2 per cent. of the total ore crushed; and a cyanide plant consisting of two tiers of 33 ft. vats, five in each tier, fed by revolving pipe-die tributers. The slimes overflow from the upper settling tanks through gates with adjustable outlets, and thence to a large canvas-plant, which efects only a small saving. This slimes product, of which about 100 tons escape per day (or 38 per cent. of the total ore crushed), contains about 3 per cent. of dry solids. Of this approximately 93 per cent. will pass a 200-mesh screen. The slimes range in value between $3.90 and $4.87 per ton, the values being about equally distributed between gold and silver. The actual averages for ore and slimes during the years 1900-

Jan 1, 1904

By R. I. Jaffee, E. S. Bartlett, D. N. Williams

The oxidation resistance and fabricability of molybdenum powder-metallurgy alloys containing up to 20 wt pct nickel in the form of a fine dispersion were studied. The effects of dispersion distribution and of amount and type (pure nickel or nickel compounds) of additive were considered. A definite improvement in oxidation resistance was observed, but the amount of improvement fell far short of requirements for an oxidation-resistant alloy. Fabricability by hot-rolling was limited. INVESTIGATIONS at Ohio State university1 and Battelle Memorial institute2 have indicated that the attainment of a truly oxidation-resistant molybdenum-base alloy for high-temperature service, with the coincident retention of high-temperature strength and toughness, will be a difficult, if not impossible, feat. Among the most promising alloy systems studied was the molybdenum-nickel system shown in Fig. 1. Alloys in this system show good oxidation resistance at temperatures well above the normal melting point of molybdenum trioxide because of the regenerative formation of protective nickel-molyb-date (NiMoO4) on the surface of the alloy during exposure at high temperatures. Unfortunately, the required alloy content to obtain oxidation resistant molybdenum-nickel alloys far exceeds the limits of the narrow terminal solid-solution boundary, and closely approaches the peri-tectic composition involving the brittle intermetal-lic compound, MoNi. Because of the peritectic reaction, fusion alloys are characteristically brittle, since the MoNi phase, being the last to form, tends to occur as a continuous grain-boundary network around each molybdenum grain. An added problem with this system is that the protective nickel-molybdate layer formed at high temperatures is unstable, undergoing one or more allotropic modifications upon cooling. The volume changes associated with this modification during cooling are such as to cause violent expulsion of the protective molybdate coating from the surface of the piece. This is, of course, quite detrimental in material exposed to cyclic temperature during service. The research reported here resulted from an attempt to overcome the aforementioned problems associated with the molybdenum-nickel alloys primarily by controlling the amount, size, and location of the MoNi phase. By using powder-metallurgy techniques of alloy preparation and sintering the blended molybdenum-nickel powder mixtures at a temperature below the peritectic reaction temperature, molybdenum-nickel alloys with a randomly dispersed MoNi phase were produced. MATERIALS The molybdenum powder used in the preparation of alloys for this study was commercial hydrogen reduced, minus 325-mesh (Tyler) material. Master alloys, by which nickel was added, consisted of elemental carbonyl nickel powder (12 average particle size), an alloy of 50 wt pct Ni-50 wt pct Cr, and compounds of MoNi, Ni,Si, and Ni2B. The nickel-chromium powder was prepared by filing a vacuum-arc-melted ingot, separating impurities magnetically, and screening to minus 200-mesh. The MoNi powder was prepared by pulverizing a hydrogen-sintered powder-metallurgy compact to minus 325-mesh material. Further sizing of this powder for study of effects of dispersion distribution was accomplished by air classification of the minus 325-mesh powder. The Ni2Si and Ni2B powders were prepared by crushing vacuum-sintered powder-metallurgy compacts to minus 200-mesh material. EXPERIMENTAL PROCEDURE Specimen Preparation—The general procedure followed in the preparation of alloys for testing is described as follows: 1) Blending. Either hand-blending of the powders in a ceramic mortar and pestle for X 1/2 or mechanical blending was used. Hand-blending seemed preferable for optimum homogeneity. 2) Compacting. Most of the blended powders were pressed to green compacts at pressures of 15 tons per sq in. in a single-action die, although some were pressed at 80 tons per sq in. A 1 X 11/4 X 1/4-in. green compact was the standard size for oxidation test material, and 7 X 1/2 X 1/4-in. compacts were used for fabricability test specimens. 3) Sintering. All green compacts were sinteredat

Jan 1, 1959

Abdul-Ahad. A., Student, Montana School of Mines, Residence Hall Butte, Mont. '39 Abramovits, Charles, Student, Case School of Applied Science Cleveland, Ohio. '37 Abreu, Ovidio M., Student, Univ. of Nevada Reno, Nev. '38 Acker, Voscoe, Student, Agricultural & Mech. College of Texas College Station, Tex. '39 Adams, Albert, Student, New Mexico School of Mines Socorro. N. M. '38 Adams, Charles W., Student, Michigan College of Min. & Tech Houghton, Mich. '39 Adams, Hugh T., Jr., Student, Univ, of Oklahoma Norman, Okla. '39 Adams, Jack L., Student, Univ. of Oklahoma Norman, Okla. '39 Adams, Jack M., Student, Univ of Alaska College, Alaska. '39 Adams, Lewis J., Student, Agricultural & Mech. College of Texas, Box 2514, College Station, Tex. '39 Adams, Robert E., Research Engr., Battelle Memorial Inst Columbus, Ohio. '38 Adamson, George M., Jr.. Student, Univ. of Utah Salt Lake City, Utah. '39 Adkisson, J. F., Jr., Student, Agricultural & Mech. College of Texas, Box 1003, College Station. Tex. '38

Jan 1, 1939

By H. E. Lee, P. C. Feddersen

846 . . . Metals Transactions, Vol. 185 T. J. WOODSIDE*—In the paper it was stated that many of the A. S. and R. plants probably used a process patented by Roscoe Teats in 1930. I might describe

Jan 1, 1950

By H. H. Hausner, S. Storchheim, J. L. Zambrow

The solid state bonding of aluminum to nickel was studied as a function of temperature, pressure, and time at pressure. The initial results indicated that as the reaction conditions were varied, marked changes in tensile strength occurred. Plots of the log penetration coefficient vs the reciprocal of absolute temperature for various isobars were straight lines displaced from each other. THE techniques of bonding different metals to A each other include brazing, welding, welding by application of a molten phase, and solid state welding without any molten phase present. This last technique, the pressing of metals either at room temperature or at some temperature below the melting point of the metals to be joined, seems to offer interesting possibilities for bonding purposes. However, this technique has not been completely investigated, and very little is known about the diffusion phenomena which occur during solid state welding. Some previous work on the effect of pressure on diffusion1 was inconclusive. This paper is concerned with an investigation regarding the effect that the processing variables, such as pressure, temperature, and time at pressure, have in solid state bonding. The tests were made with aluminum and nickel and special emphasis was given to the strength of the bond between these two metals and to the intermetallic penetration rate during the bonding process. It seems that the effect of pressure on the intermetallic penetration is of particular importance for practical purposes and this effect was therefore studied in detail. Procedure Apparatus: The means of solid state bonding used for this study was that of the hot-pressing technique. This method requires the equipment pictured in Fig. 1 and involved the following procedure. The two metals to be bonded were placed in an aquadag lubricated 18-4-1 tool steel die, 16 in. high by 1.440 in. ID, between punches of 1.366 in. diameter made of the same material. A thermocouple

Jan 1, 1955

NEW YORK LOCAL SECTION Executive Committee Louis D. HUNTOON, Chairman ARTHUR S. DWIGHT, Vice-Chairman THOMAS T. READ, Secretary, Woolworth Bldg., New York, N. Y. E. MALTBY SHIPP, Treasurer GEORGE F. KUNZ W. DE L. BENEDICT Meeting, Jan. 16, .1914 A meeting of the New York Local Section of the American Institute of Mining Engineers was held at the Engineering Societies Building, 29 West 39th Street, New York City, Jan 16 1914 the Chairman, -L. D. Huntoon, presiding. Forty members weld present. In the absence of the Secretary, C. A. Bohn was appointed Secretary pro teen. N. H. Darton, Geologist of the U. S. Geological Survey, delivered an address on. The Occurrence of Gas in Coal, illustrated by lantern slides of charts, curves, and tables showing various features of gas occurrences. J. W. Richards, J. T. Beard, W. L. Saunders, L. D. Huntoon, and Mr. Darton participated in the discussion which followed the address. THOMAS T. READ; Secretary.

Jan 3, 1914

By Eugene P. Pfleider, Claus Freyberger

Generally, the different methods of financing new mining projects are not well understood by the engineers and supervisory personnel. Nor are the effects of these alternatives on depletion, taxes and profitability readily apparent to even the sophisticated management personnel without the aid of cash flow studies. Fortunately, with the advent of the computer it is possible now to simulate many different combinations of 1) equity, 2) loan and 3) production payment financing with little effort. A general computer program for cash flow analysis of mining ventures has been developed and applied as a case example to a 1967 feasibility study of the Underground Mining of Minnesota Taconite. The effects on profitability as measured both in rates-of-return and present value are presented for various financing combinations. In addition, percentage depletion rates were altered so as to measure the impact of this statuatory allowance. Based on the cost data as presented in the aforementioned 1967 feasibility study, and assuming 7% loans, the rates-of-return vary from 9. 9% to [00] % on equity variations and from 9. 9% to 11.4% on total invested funds.

Jan 1, 1969

By J. Campbell

The negative pressure developed within a solidifying sphere of pure iron is investigated theoretically assuming an elastic-plastic model. The maximum hydrostatic tension attainable is shown to be an order of magnitude smaller than that required for the homogeneous muclealion of pores in the liquid cove, and four orders of magnilude smaller than that predicted from) a rigid shell model. It is well-known that liquids can withstand large hydrostatic tensile stresses, or negative pressures. The various experimental investigations of the tensile strengths (often called the fracture pressures) of liquids are reviewed by Dean,1 and the theoretical attempts at estimating fracture pressures are critically assessed by wakeshima.2 Using Fisher's3 quation, the fracture pressure of pure liquid iron is about -70,000 atm, which may be too large by as much as a factor of 4, but is certainly correct to within an order of magnitude.' In view of the great importance of the problem of the nucleation of shrinkage cavities in castings it is of interest to determine exactly what tensile stresses can exist in the residual liquid in a solidifying casting; it has often been assumed that, because of the very low strengths of solid metals near their melting points, no interior stresses are developed at all. Nussey4 has determined theoretically the pressure in the liquid core of a solidifying metal sphere assuming that the solidified shell does not deform (i .e., is perfectly rigid), so that because of the contraction accompanying solidification (a) (about 3 pct for most metals) the progressive deposition of solid onto the inner surface of the shell causes the remaining liquid to be expanded to make up this difference in volume. This leads to a relation between the pressure P in the liquid, the initial pressure, PO, the bulk modulus of the liquid, K, and the inner and outer radii of the solid shell, o and b, respectively:

Jan 1, 1968

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who registered at Institute headquarters during the period Nov. 10 to Dec. 10, 1915: F. Lynwood Garrison, Philadelphia, Pa. E. Fleming l'engle, Costa Rico, C. A. William J. Lakeland, Burma, India. Fred Maccoy, El Oro, Mexico. Dwight E. Woodbridge, Duluth, Minn. 0. N. Scott, Toronto, Ont., Canada. Chester A. Fulton, Yonkers, N. Y. K. P. Swenson, Tokyo, Japan. Willet G. Miller, Toronto, Canada. - H. L. Mead, New York, N. Y. L. G. Huntley, Pittsburgh, Pa. E. DeGolyer, Norman, Okla. L. E. Howard, Lockport, N. Y. J. S. Lane, New York, N. Y. H. W. DuBois, Philadelphia, Pa. T. V. Nonactre, Argentina. Howard R. Stewart, London, England. N. H. Darton, of the U. S. Geological Survey, has returned to Washington after a long season of field work in New Mexico investigating the prospects of finding potash deposits in the Red beds.

Jan 1, 1916

By Paul Munoz

TRINIDAD, which has never been. seriously consid-ered as a large oil producer, has recently taken a new lease on its oil life through active development work being carried on by a newly organized American company that has been conspicuously successful in the short time in which it has operated on the island. From an oil operator's point of view Trinidad pos-sesses numerous natural advantages which are not found in any other oil producing country. The climate, while tropical, is healthy. The nights are always cool. Deep-water shipping ports in protected waters are available within short pipe-line distance from the pro-ducing fields. The distance from Trinidad to the At-lantic seaboard of the United States is less than from the Gulf Coast or from Mexico. The labor supply is abundant and can be had at reasonable rates. The island enjoys a good, stable government under British rule and is traversed by a net-work of excellent govern-ment roads. From a production standpoint the fields being de-veloped by Trinidad Oil Fields, Inc., the company re-ferred to above, present interesting problems which are being successfully solved. The oil sands are extremely fine; some of them having over 50 per cent passing 100- mesh screen and, with the exception of the Palo Seco field, the sands are loose, with shale-breaks and shale capping and with rock pressures running up to 600 lb. per square inch. Rotary drilling is universal, as the formations encountered are soft Tertiary shales, clays, sandy shales and sands, with occasional sandstone and lime shells, which are easily drilled with the rotary. As high as 600 ft. of hole in 24 hr. has been made in some of this company's wells. Production is at present obtained at depths ranging from 500 to 2500 ft. but further development will probably result in deeper pro-duction being obtained. The oil being produced ranges from 21 deg. to 37 deg. Bé gravity and is all asphaltic base oil.

Jan 7, 1927

By A. B. Stevens, C. J. Coberly

The absolute porosity of a rock or sand may be defined as the volume of the interparticle space expressed as a percentage of the total rock volume. The effective porosity as contrasted with the absolute porosity is the volume of the interparticle spaces which intercommunicate with passages of sufficient size to permit the entrance or recovery of gas or oil, also expressed as a percentage of the total rock volume. A knowledge of effective porosity is of prime importance in estimating the ultimate recovery to be expected from oil and gas-bearing formations. The determination of the effective porosity of a rock includes the measurement of two values: (I) the volume of the rock as a whole, and (2) the volume of the grains and sealed pore space. This paper deals with a new apparatus which has been called a "hydrogen porosimeter" for determining the volume of the grains and the sealed pore space. This volume is determined by means of the pressure relations established in the instrument by the introduction of a known quantity of hydrogen. The Hydrogen Porosimeter The apparatus used in this work consists of an upper chamber for measuring the gas, a lower chamber for holding the sample to be tested, a gage for measuring the pressures, a tank of hydrogen, and the necessary connections. (Figs. 1 and 2.) Of the several gases that might be used for this work, hydrogen has been chosen for three reasons: (1) it deviates less from the gas laws than most gases; (2) it readily penetrates the sample; (3) it is absorbed less than most gases by the solids and liquids with which it may come in contact. Method of Operation After placing the sample to be tested in the lower chamber, the apparatus is thoroughly flushed with hydrogen to remove all air from the system, which is then brought to atmospheric pressure Po. The valve connecting the two chambers is next closed and the pressure in the upper chamber is brought up to a pressure PI by admitting gas from the tank.

Jan 1, 1933

By J. King Hoyt

IN both Sweden and England rapid progress is being made in metallurgical development, and the steel industry in both countries is distinctly on the mend. There has been some industrial trouble in Sweden in the iron mines and the wood pulp mills, but at the same time all the steel works have a sufficient stock of pig iron and ore to continue their operations for many months to come. Consequently the strike, unless long protracted, will not affect the output of steel in Sweden. Several of the steel manufacturers in Sweden, most notably Forsbacka and Sandviken, have been very suc-cessful recently in securing large orders, particularly from the continent, for ball-bearing steel, both hollow and solid. Whereas some years ago they ran into-se-rious competition with the German mills, the quality of the steel from these Swedish mills is such that they are now firmly established, and are selling some of the lead-ing manufacturers of bearings on the Continent, as well as automobile manufacturers. The secret of their success seems to lie in a better selection of ores, in more careful control of blast-fur-nace operations and better equipment. Rule of thumb in steel making is taboo, and strict reliance is placed on the laboratory. They are constantly experimenting, and metallurgists and chemists are sent to different countries for study and investigation. In their native ores they have, of course, a unique advantage in pos-sessing iron ores extraordinarily free from phosphorus. At Forsbacka, they are not content with the ordinary chemical analysis of the ingot; but also test the physical properties, as well as make metallographic investiga-tions for slag inclusions, segregations and oxides. In both England and Sweden they watch the nitrogen con-tent of the steel very carefully, a feature which does not appear in the ordinary analysis. In testing carbon, they do not use the color test, but employ an electric .induction device.

Jan 7, 1928

One Hundred and Twelfth Meeting of the Institute, Monday, February 14, to Thursday, February 17, inclusive, 1916 COMMITTEE ON ARRANGEMENTS DAVID H. BROWNE, Chairman. BRADLEY STOUGHTON, Vice-Chairman. LAWRENCE ADDICKS, BURR A. ROBINSON, P. E. BARBOUR, E. M. SHIPP, G. D. BARRON, JOSEPH STRUTHERS, J. V. N. DORR, E. B. STURGIS, J. R. FINLAY 'R. H. VAIL. L. D. HUNTOON, Hotel Accommodations.-The Committee on Arrangements is canvassing a number of hotels in New York City, securing .wherever possible special rates to members and guests for the clays of the meeting. It is possible to secure good accommodations on very reasonable terms in New York City if one knows where to look for them. A list of hotels and rates will be published in the final announcement of the meeting, which will go to the members about the middle of January, in order that those who desire to secure good hotel accommodations at a reasonable mice may have the information.

Jan 1, 1916

By T. Fraser, R. L. Sutherland

Under a cooperative agreement between United States Bureau of Mines and the Truax-Traer Coal Company, some operating-scale experiments have been made with the cyclone thickener in the preparation plant of the Shamrock No. 1 mine at Kayford, West Virginia. These tests were made with a 14-in. cyclone of the type developed by the Dutch State Mines in Limburg. It was applied experimentally to the thickening of solids in washery water to obtain performance data to show the range of sizes that may be recovered and other operating characteristics that would indicate the field of usefulness of this device in coal preparation practice. This is a progress report only. It covers results obtained in a series of 17 tests of the operation of what has been considered a unit of commercial size operating on suspensions of fine coal mixed with a relatively small amount of freeimpurities. The underflow material, after further dewatering in centrifuges, is a marketable grade of coal.

Jan 1, 1949

PERSONAL (Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who registered at Institute headquarters during the period Oct. 10 to Nov. 10, 1914: Jintaro Kojima, Ashio, Japan. E. R. Hinckley, Seoul, Korea. J. Homer Stover, Trenton, N. J. S. A. Taylor, Pittsburgh, Pa. Kirby Thomas, New York, N. Y. Lawrence Addicks, Douglas, Ariz. Keijiro Nishio, Tokyo, Japan. Noel Cunningham, Bethlehem, Pa. Alexander K. Hamilton, Chicago, Ill. E. C. Vigeon, London, England. Harold N. Lawrie, Portland, Ore. S. E. Fairchild, Jr., Philadelphia, Pa. C. Spence Thomas, Cardiff, Wales. W. C. Schmidt, Jr., New York, N. Y. Henry Tackmann, New York, N. Y. Kenneth C. Browne, New York, N. Y. Dr. David T. Day has resigned his position with the U. S. Geological Survey and opened an office at 1331 F Street, N. W., Washington, D. C., for practice as a consulting engineer.

Jan 12, 1914

By T. Koulomzine

The theory of the Askania magnetometer, as well as a complete discussion of all factors influencing magnetometer readings, is very ably described by J. Wallace Joyce. We will assume that the reader is thoroughly familiar with this theory and we will use whenever possible the same notations for the physical values involved in the theory. On the other hand, we believe that the principal formulas of the magnetometer can be deduced much more easily by the use of differential calculus than by the methods employed by Joyce. Consequently, we are presenting herewith a resume of the theory of the vertical magnetometer in order to determine the correct formula of the temperature coefficient which we propose to compensate.

Jan 1, 1949

By Norman P. Goss

The Chairman.—Thank YOU, Mr. Goss Gentlemen, I believe we have heard one of the finest papers, especially since Mr. Goss has been very generous in his frank discussion of continuous casting. One point he has brought out which 1 think some of us have not thought through to the same extent that he has—that the continuous casting process offers the small producer an opportunity to compete with the larger, more conventional and presumably better established industries. The meeting is now open for discussion. Are there any questions concerning the first two papers? J. A. Malone.*—I should like to ask Mr. Goss whether there is any special problem involved in the first part, the upper part of the mold before he gets to the first graphite lubricant area. N. P. Goss.—You mean in the forming chamber where chilling first takes place? J. A. Malone.—Yes. N. P. Goss.—So far I have not had any trouble in this part of the setup. My only

Jan 1, 1945

By N. A. D. Parlee, I. D. Shah

ThIS reports on some work done on the solubility and diffusivity of oxygen in liquid silver. Solubility. Improvements in the measurement of the solubility of oxygen in silver and silver alloys were made because precise data were needed for calculating diffusion coefficients of oxygen in these alloys. The apparatus and the procedure used were similar to those of Parlee and Sacris.' The main improvement was in the temperature-measuring technique. A MV30 mullite protection tube containing a calibrated Pt-Pt, 10 pct Rh thermocouple was inserted in the reaction tube from the top through a vacuum-tight swage-lok fitting. The protection tube was well-immersed in the liquid silver, which was heated by induction. A Leeds and Northrup potentiometer was used in connection with the thermocouple. All runs reported were made at 1 atm. The temperature range investigated varied from 940" to 1200°C. The ternary point in Ag-0 phase diagram2 is at 939°C and 0.32 wt pct O. This point was reinvestigated using the above-described apparatus and was found to be at 939°C and 0.315 wt pct 0. It was determined by observing the sudden evolution of oxygen at this point while the solubility measurements were made. The point was easily reproducible if precautions were taken to keep the liquid silver essentially in equilibrium with oxygen and to lower the temperature very slowly. All of the results of this new solubility investigation are plotted in Fig. 1. They are represented by the "least-squares" line shown in the figure and the following equation for solubility at po2 = 1 atm: log% O =695.4/T - 1.086 This equation differs only slightly from that proposed by Parlee and sacrisl and that of Diaz, Masson, and Richardson.3 The points of Parlee and Sacris, using an optical pyrometer, are shown for comparison.

Jan 1, 1968