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By CHRIS A. HARTNAGEL

For the second consecutive year, the production of crude petroleum in New York has fallen below the 5,000,000-bbl. Mark that had prevailed previously since 1937. In 1945, the output totaled 4,658,000 bbl., a decrease of slightly more, than one per cent from the 1944 production. This total represents 2 per cent of the stripper-well production of the United States, which in turn is I 3 per cent of the total annual yield of the nation's petroleum.

Jan 1, 1946

By Joachim J. Hauser

William F. Hosford, Jr. (Massachusetts Institute of Technology)—Dr. Hauser has used a very interesting method to study the interaction of dislocations on different slip systems, but it should be pointed out that the analysis of the experiments is subject to a serious criticism. He states that "the effect of the compression can be adequately described by one slip system." The effect of frictional constraint during the compression makes this quite unlikely. When a block of metal is compressed its lateral expansion requires a sliding of the metal over the compression platens. The role of friction in the interface between the deforming metal and the platens is to increase the normal force required for the compression. Analyses1213 have shown that, in general, the additional force, p, required for the compression is a function of l/h where is the coefficient of friction, I is the length of the speci- men in contact with the platens. For a constant COefficient of friction, isho' shows that P should increase exponentially with pl/h for both plane strain and axially symmetric compression. For a compression specimen, Fig. 7, whose cross section perpendicular to the compression axis is a rectangle whith one dimension L, much larger than the other W, a much larger force would be required for appreciable flow parallel to L than for flow parallel to U7. Therefore lateral strain in the W direction, EW, should be much greater than the lateral strain in the L direction EL. Since L/H = 14.5 for Dr. Hauser's crystals, and since no lubrication was used, it seems questionable that appreciable lengthening of the crystals could occur. Because the theories of frictional constraint have been derived for isotropic polycrystalline materials, it was decided to make experimental measurements on a single crystal. A section 3.590 in. long was sawed from an aluminum single crystal with a square section of 0.249 in., so that L/W= 14.4. This crystal was tested in compression between dry ground steel platens. Fig. 8 shows the orientation of the crystal and the axis of compression. The face for compression was chosen so that the operation of the single-slip system which would be predicted in the absence of friction would lead to a larger strain in the length direction than in the width direction. The dimensional changes of the width and length as well as the height were measured frequently during the compression with micrometers. Width strains were calculated from the average of readings near each end and at the center. A plot of the length strain, EL, against the width strain E w is given in Fig. 9. The slope indicates that the EL amounted to only 2.5 pct of cw. Other compression tests on similar crystals with shorter lengths also showed severely limited elongation. Even for a crystal with L/W = A.0, EL was only about 26 pct of cw. Because of the frequent interruptions of the tests for dimensional measurements should have decreased the frictional constraint by allowing a reseating of the platens, even smaller elongations under continuous testing seem probable. These tests on long narrow crystals show that essentially plane strain conditions prevailed. We may assume that Dr. Hauser's crystals deformed similarly. That the compression can be described by the

Jan 1, 1962

By Francis A. Thomson

DO the curricula of our mineral technology schools prepare their graduates to meet properly the full range of their responsibilities in after life? An unequivocal "no" could be returned to this question, because training and experience in professional work are quite as important as adequate college preparation. Furthermore, a had curriculum with a splendid corps of men doing the teaching and a competent body of students doing the learning will produce a better result than an ideal curriculum in the hands of unqualified teachers and poorly prepared students.

Jan 1, 1937

By William B. Plank

AGAIN the records show an unprecedented enrollment of students in the mineral technology schools of the United States and Canada. In the current year, 1938-'39, 9619 students were resident in the 53 schools of the United States arid 1014 in the six schools of Canada. These data are from my fifth study of the mineral technology schools of the United States and Canada. the last previous study having been made for the year 1936-'37. The undertaking as previously was made under the auspices of the Mineral Industry Education Division of the A. I. M. E. The data or, the various schools were collected in the same way as for former studies.

Jan 1, 1939

THE research and policy committee of the Committee for Economic Development, a non-profit research organization composed of leaders in industry and the professions, including such prominent figures as Dwight D. Eisenhower, Paul G. Hoffman, and Charles E. Wilson, recently published a report entitled "How to Raise Real Wages." Since its founding in 1942 the CED has initiated many objective studies on matters of national economic policy, and has gained a fair measure of prestige from its activities. The CED's latest report cites the more than three- fold rise in real wages in the United States in the past 50 years and attributes the accompanying improvement in the standard of living to the great in- crease in production per man hour. The report states that in order for production to continue rising in the future with the attendant increase in real wages four basic conditions must be manifest: (1) better methods, (2) more capital, (3) better training of workers, and (4) better management. The report cautions that although prospects for increases in output per man hour are good "it is desirable that steps be taken to encourage such a rise."

Jan 8, 1950

By L. Weaver

THE Tennessee Copper Co.'s mines are in the southeast corner of the state of Tennessee. Polk Co., in the well-known Ducktown copper basin. Their new circular production shaft will eventually be the only ore hoisting shaft, and is located for handling ore from Boyd, Calloway, Mary, and Cherokee mines. A circular, rather than a rectangular, shaft was decided upon because: 1-The circular shaft section is stronger when lined with concrete. Reinforcing steel was not required, thus reducing lining cost by one- quarter. 2-Water sealing was desired; it was thought it could best be done with a concrete lining followed by pressure grouting to eliminate water seeps. 3-The shaft labor saving equipment could best be used in a large opening, so the round section was made for economy, sinking, mucking, concreting and water sealing. Less shaft steel is used than could have been possible with steel sets. There are no posts required; center beams and Tee plate assembly placed at 10 ft hold the 100 lb steel guide rails. The shaft is 12 ft 7 1/2 in. ID of the concrete walls. This is large enough for two 10-ton hoisting skips and a ladder compartment. One of the skip compartments is for hauling equipment. The grouting equipment was a 2%xlO-in. Gardner-Denver grout pump, air powered and developing 1000 lb pressure. A grout mixer, also air driven, fed the mixed solution into a tank coupled to the pump suction. Grout materials used were mostly water and Portland cement. Some Bentonite was used to seal porous ground near the surface.

Jan 11, 1950

By R. E. Lund

Josephtown Smelter employs the St. Joe-developed electrothermic process for producing zinc metal and zinc oxide. The process uses resistance-type electric furnaces. Flow of current through the sintered ore and coke charge develops the energy required for smelting at the reaction sites. To produce zinc metal, the furnace off-Gases bubble through a large "U"-tube filled with molten zinc which condenses the zinc to liquid; the metal is then mechanically cast into slabs. To produce zinc oxide, the furnace vapors burn in air and the resultant powders are collected. The smelter comprises three distinct circuits. One circuit produces American Process zinc oxide and high grade metal; another circuit produces tailor-made alloys of controlled lead and cadmium content; the third circuit produces prime western zinc metal and feedstock which is refined into special High grade metal and French Process zinc oxide. The roasting circuit utilizes multiple-hearth furnaces for deleading the zinc concentrates; fluid bed and suspension roasters are employed for desulfurization. Sintering produces a hard, porous furnace feed. The flexible smelting process is adaptable to consuming various kinds of secondary material. Extensive residue treatment accomplishes high overall zinc recovery. Smelter by-products include sulfuric acid, cadmium, and mercury.

Jan 1, 1970

By CHARLES W. BENTON

THE following paragraphs comprise such information as the Secretary has been able to obtain concerning the members and associates whose deaths have been reported. Further particulars or corrections of errors, and biographical data concerning deceased members or associates not already noticed in this way, are solicited. Charles IV. Benton was born at Kezar Falls, Maine, Nov. 12, 1843. We have no accurate knowledge concerning the early part of his career. In 1871 he engaged with the N. Y. Honduras Rosario Mining Co., at San Juancinto, Honduras, C. A., and later was employed at the Monserrat mine at Yuscaran, and at Santa Lucia, Honduras, with the Tenero Mining Milling Co. of Pennsylvania. In 1897 he became a member of the Institute. At the time he was stricken with his last sickness he was employed at the Paymaster mine at Tucson, Ariz. He died at Fairmount, Denver, Colo., Sept. 9, 1907. William R. Boggs, Jr.-The notice in the Bulletin for January was incorrect in saying that the murder of Mr. Boggs occurred while he was employed as metallurgical. manager by Mr. W. B. A. Dingwall, at La Maroma, San Luis Potosi, Mex. Mr. Dingwall writes that in March, 1907, Mr. Boggs left him, to return to his home at Winston, N. C., whence he. subsequently went to Durango, Mex., to take, with the Topia Mining Co., a position which he occupied at the tine of his death, Nov. 17, 1907. Mr. Dingwall says that, while in his service, Mr. Boggs never had any trouble with the workmen, but was esteemed and liked by them, as by all who knew him ; and adds, injustice to the State of San Luis Potosi, that the population, even in the mining-camps of that State, is orderly and law-abiding, and that the authorities are vigilant and just. Our

Mar 1, 1908

By Clarence Zener

THE heat-treatment of steels will not pass from the stage of an art into that of a science until the mechanism of the phase transformations associated therewith is thoroughly understood. Such an under- standing will involve two distinct types of inquiry: (I) the direction of the trans- formation, (2) the speed of the transformation. The first type of inquiry, which involves only the equilibrium relations between the various phases in steel, is the subject of the present and of a succeeding article; the second type, which involves the kinetics of transformations, will be the subject of a later article. In order that a theory of equilibrium relations may give useful information, certain experimental data must be put into the theory. It is customary for these data to be of a thermal nature. In the system discussed here in steel such thermal data are very scarce. In medium-alloy steels another type of data might possibly be used. In these steels the concentration of solute is so low that it may be possible to use the approximation of dilute solutions, an approximation that leads to linear relationships. The unknown functions, or constants, may then be determined in some cases from the binary iron- alloy system and in other cases from the ternary iron-carbon-alloy system. From the functions, or constants, so determined may then be computed the equilibrium relations in more complex medium-alloy steels. In the present article this second approach is used, the necessary experimental data being obtained from the simple binary and ternary equilibrium diagrams. FUNDAMENTAL EQUATIONS In this article are derived the equilibrium relations between the gamma, alpha and cementite phases. In these three phases all important alloying elements except carbon form substitutional solutions, each alloying atom occupying a potential site for an iron atom. Carbon, on the other hand, forms an interstitial solution. In the face-centered cubic gamma phase, the interstitial positions are at the center of the unit cube and at the centers of the cube edges. There are therefore four interstitial positions per unit cell, or one per iron atom. In the body- centered cubic alpha phase, the interstitial positions are probably at the face centers, and also at the centers of the edges, which are crystallographically equivalent to the face centers. There are therefore six interstitial positions per unit cube, or three per iron atom. In cementite, (Fe, Alloy)3C, the carbon atoms may be regarded as filling all the lattice positions of a given type. The introduction of the fundamental equations of equilibrium has presented the author with a quandary. These equations are formally so similar to other equations that have been derived1,2 for related systems that they may appear to some readers

Jan 1, 1946

By Jay J. Burns

TWO zinc concentrating mills are operated by the St. Joseph Lead Co. in St. Lawrence County, N. Y. The Edwards mill is operating at present only sixteen hours a day treating 400 tons daily. The metallurgy at Edwards presents no unusual problems therefore this discussion is mainly limited to the metallurgy of the Balmat ore. The Balmat mill has a capacity of 1,250 tons per day and the operating crew consists of three shift bosses each with five millmen per shift. Two crusher operators work on each of two shifts and one cleanup man on day shift. The repair crew is made up of a foreman and three repairmen, one of the repairmen being capable of taking over any operating job in the mill from shift boss down. Each millman is capable of handling the next job in line and several men in the yard crew are broken into handling the start-off job in the mill so that temporary shortages of men do not cause extensive overtime. Sphalerite, pyrite, and galena, the principal ore minerals, occur in a gangue of calcite, dolomite, and silicates, especially diopside, plus tremo-

Jan 1, 1947

The Garfield plant of the American Smelting & Refining Company is situated about seventeen miles west of Salt Lake City, on the Los Angeles & Salt Lake Railroad, and has freight service by the Denver & Rio Grande Western. Western Pacific and Bingham & Garfield Railways. The site lies between the picturesque Great Salt Lake, with its mountain islands and the northern point of the Oquirrh Range, which forms the western boundary of the Salt Lake Valley.

Jan 1, 1925

By G. K. Burgess

(New York Meeting, October, 1913.) 1. COOLING AND HEATING CURVES BY G. V. BURGESS AND J. J. CROWE. § 22. THE results published in Professor Howe's paper 10 of our determinations on the Ac3 and Ar3 points for a series of commercial carbon steels 11 containing manganese in varying proportion, represent the average temperatures found by taking several (4 or 5) heating and cooling curves. The accompanying curves, Figs. 6 and 7, are, for each steel, the first heating and cooling curves as obtained by' the inverse-rate method of Osmond, using a cylindrical chronograph sensitive to -0.1 sec. for recording .time. Simultaneous observations were also taken by the differential method with a platinum neutral and plotted by Rosenhain's derived differential method and gave substantially the same results, the curves having sensibly the same contours in both cases.12. The observations were taken in vacuo on cylinders 5/8 by 1 in. in length bored to center with a 1/8-in. hole to receive porcelain insulated thereto-couple, and inclosed in an out- and in-glazed Berlin porcelain tube heated electrically by, platinum foil wound on the tube. The vacuum was usually better than 0.1 mm. The heating and cooling of the furnace was automatically controlled by a salt-water rheostat with shaped electrodes, giving a uniform rate of heating and cooling.

Jan 6, 1913

By John M. Kelly

New Mexico produced 39,475,388 bbl. of oil in 1944, the greatest amount in one year in the oil history of the state. This production was 593,046 bbl. or 1.25 per cent more than in 1943. New Mexico retained its position as the seventh largest oil-producing state. The maximum per well allowable on Jan. I, 1944 was 48 bbl. daily and at the end of the year it was 45 bbl. daily. Allocations as set by the New Mexico Oil Conservation Commission closely followed the recommendations made by the' Petroleum Administrator for War. The average daily pipe-line runs were within 4 per cent of the allocation. Production by counties was as fol1ows;Lea County, 33,509,548 bbl.; Eddy County, 5,504,498; Northwestern New Mexico 461, 342. Drilling activity for New Mexico in 1944 was well above that of 1943, with 362 completions. Of these, 283 were oil wells, 12 gas wells and 67 dry holes. The ratio of dry holes to producers, about I to 4, was an improvement over 1943. Wildcat drilling during 1944 was responsible for the discovery of six new fields and the extension of two present producing areas. Drilling records were established in New Mexico during 1944 with the deepest producer ever completed, the Humble Leonard Oil Company's No. I at 11,969 ft., in the Ellenburger section of Ordovician age near Jal, Lea County. The discoveries in Lea County during 1944 were as follows: West Lovington field, where Fred Turner, Jr. drilled his No. I State B .in C SE SW sec. 4-17-36 and completed it for 122 bbl. of oil in 8 1/2 hr., in the San Andreas section of Permian age. The Tonto field, where the T-exas Company completed its No. I Baskin at a total depth of 3586 ft. in Seven Rivers lime of Permian age, with an initial production of 254 bbl. of oil in 21 hours. The Drinkard area, where the Gulf Oil Corporation's Drinkard No. I flowed 782 bbl. of oil in 14 hr. from the Yeso section of lower Permian age, thus opening the first lower Permian production in the state. The total depth of this discovery was 6508 ft. and oil was 38.8" A.P.I. gravity. The Dublin area, where the Humble Oil and Refining Co. established a drilling depth record of 11,969 ft. drilling and completing its No. I Leonard Oil Co. well in the Ellenburger lime of Ordovician age. This well flowed 221 bbl. of oil per day, of 48.9º A.P.I. gravity oil. It is in sec. 12-26-37. The new pay horizon discovery of the Continental Oil Co. in the Skaggs area, where the company completed its Skaggs B-23 No. 2 in sec. 23-20-37 for 236 bbl. of oil in 21 hr. from the Wolfcamp section of lower Permian age, at a total depth of 7725 ft. This well was drilled to granite at 10,465 ft. and plugged back to the Wolf-camp for a new pay zone completion.

Jan 1, 1945

By John G. McLain

OF all the zinc that the world consumed in 1936-'38 the United States took about 31 per cent, and almost 14 per cent of the world's zinc supply in that period was used for galvanizing purposes in the United States. Further examination of the statistics shows that about 71/2 per cent (147,500 tons in 1939) of the world zinc consumption goes into the galvanizing of sheets in the United States, which is what I am going to talk about in this paper. There is nothing especially new about galvanizing; in every year since 1921 somewhere between 41 and 49 per cent of the country's zinc consumption has been used for this purpose, and yet few people not specialists in its manufacture know much about how it is made. You take an iron or steel sheet and dip it in molten zinc and there you have a galvanized sheet-that about epitomizes popular knowledge of the subject even among engineers.

Jan 1, 1941

By Ralph E. Esarey, George V. Cohee

In Indiana, 349 wells were drilled for oil and gas in the year 1942. Of this number, 125 oil wells and 21 gas wells were successfully completed and 203 were dry holes. Drilling activity declined 37 per cent as compared with that of the year 1941. This reduction was brought about largely by Federal Conservation Order M-68, restricting drilling to one well on 40 acres, in order to save steel. This Order was later supplemented to permit closer spacing of wells drilled to sandstone formations in southwestern Indiana. Most of the drilling in 1942 was in the southwestern part of the state. Posey County ranked first, with 94 completions and 44 producers; Gibson County, second, with 77 completions and 38 producing oil wells and 2 gas wells. There were 58 drilling operations in the state at the end of the year. During 1942 a total of 589,734 ft. of hole was drilled, of which 231,702 ft. was wildcat footage. The total initial production of the oil wells completed was 9974 bbl. and of the gas wells, 11,148,000 cu. ft. (Table 2). Of the 349 wells completed, 122 were wildcat wells (Table 3); 26 were completed as oil wells; 17 were extensions to proven fields and 9 discovered new pools. Posey County was foremost in wildcat drilling, with 37 wells completed (Table 6). Thirty-five per cent of the wells drilled in 1942 were wildcat, as compared with 25.5 per cent in 1941. It is anticipated that the percentage of wildcat wells drilled in 1943 will be greater, although the total number ol ,wells drilled in the state will probably be less. The new discoveries in Indiana in I942 were, for the most part, one-well pools in the southwestern part—in Posey, Gibson and Spencer Counties (Table 4). Most of the development in pools took place in the . Hazelton and Kirksville pools in Gibson County, Mr. Vernon pool in Posey County and the Vernon Heights pool in Vander-burgh County. Deeper production was obtained from the Osage limestone in the Hazelton pool at a depth of 2402 ft., 650 ft. below the productive McClosky limestone. The well had an initial production of 140 barrels. Extensions to 17 pools in the southwestern part of the state were successfully completed (Table 5). An interesting development during 1942 was new production from the Devonian limestone in the Dodds Bridge pool, Sullivan County. The Ohio Oil Co. deepened one of its wells, which had been producing from a shallow sand, to the,Devonian, and it was completed for an initial production of 77 bbl. Five other Devonian producing wells were completed in that area. Crude-oil production in Indiana in 1942 was 6,609,000 bbl. (Table I). The Griffin field, Gibson and Posey Counties, which produced approximately 3,550,000 bbl., accounted for more than half of the state's production. The Mt, Vernon and New Harmony fields were next in importance of production, with 684,000 and 523,000 bbl., respectively. The price of crude oil was $1.22 a barrel for the old

Jan 1, 1943

By George V. Cohee, Ralph E. Esarey

In Indiana, 349 wells were drilled for oil and gas in the year 1942. Of this number, 125 oil wells and 21 gas wells were successfully completed and 203 were dry holes. Drilling activity declined 37 per cent as compared with that of the year 1941. This reduction was brought about largely by Federal Conservation Order M-68, restricting drilling to one well on 40 acres, in order to save steel. This Order was later supplemented to permit closer spacing of wells drilled to sandstone formations in southwestern Indiana. Most of the drilling in 1942 was in the southwestern part of the state. Posey County ranked first, with 94 completions and 44 producers; Gibson County, second, with 77 completions and 38 producing oil wells and 2 gas wells. There were 58 drilling operations in the state at the end of the year. During 1942 a total of 589,734 ft. of hole was drilled, of which 231,702 ft. was wildcat footage. The total initial production of the oil wells completed was 9974 bbl. and of the gas wells, 11,148,000 cu. ft. (Table 2). Of the 349 wells completed, 122 were wildcat wells (Table 3); 26 were completed as oil wells; 17 were extensions to proven fields and 9 discovered new pools. Posey County was foremost in wildcat drilling, with 37 wells completed (Table 6). Thirty-five per cent of the wells drilled in 1942 were wildcat, as compared with 25.5 per cent in 1941. It is anticipated that the percentage of wildcat wells drilled in 1943 will be greater, although the total number ol ,wells drilled in the state will probably be less. The new discoveries in Indiana in I942 were, for the most part, one-well pools in the southwestern part—in Posey, Gibson and Spencer Counties (Table 4). Most of the development in pools took place in the . Hazelton and Kirksville pools in Gibson County, Mr. Vernon pool in Posey County and the Vernon Heights pool in Vander-burgh County. Deeper production was obtained from the Osage limestone in the Hazelton pool at a depth of 2402 ft., 650 ft. below the productive McClosky limestone. The well had an initial production of 140 barrels. Extensions to 17 pools in the southwestern part of the state were successfully completed (Table 5). An interesting development during 1942 was new production from the Devonian limestone in the Dodds Bridge pool, Sullivan County. The Ohio Oil Co. deepened one of its wells, which had been producing from a shallow sand, to the,Devonian, and it was completed for an initial production of 77 bbl. Five other Devonian producing wells were completed in that area. Crude-oil production in Indiana in 1942 was 6,609,000 bbl. (Table I). The Griffin field, Gibson and Posey Counties, which produced approximately 3,550,000 bbl., accounted for more than half of the state's production. The Mt, Vernon and New Harmony fields were next in importance of production, with 684,000 and 523,000 bbl., respectively. The price of crude oil was $1.22 a barrel for the old

Jan 1, 1943

By M. J. Pool, with Appendix by Larry Kaufman, R. W. Krenzer

Thermodynmic properties of the Cu-Mn system have been deterrrzined in the temperature range 973" to 1273°K by measuring the vapor pressure of manganese in equilibrium with alloys of compositions varying from 0.13 to 0.91 rnole fraction manganese using the Knudsen effusion technique. Activities of manganese calculated from the measured vapor pressures show large positive deviations. Calculated heats and entropies of mixing are positive with a maximum occurring at approximately 0. 7 mole fraction manganese. ThE investigation of thermodynamic properties of binary systems involving transition metals is of considerable interest at the present time. The incomplete subvalency electron levels of transition metals lead to unusual behavior in some alloys, and considerable information can be obtained by determining the thermodynamic characteristics of these systems and relating the thermodynamic behavior to observed physical properties. The Cu-Mn system, shown in Fig. 1,' provides an example of an alloy system in which the determination of the equilibrium phase diagram and various physical properties has received considerable attention, but very little work has been done on measurement of the thermodynamic properties. Elemental copper and manganese have comparable electronegatives, atomic sizes, and cohesive energies, but differ in crystal structure. They form a continuous series of solid solutions only at high temperatures and the structure varies in a continuous manner from fcc at the copper-rich end to fct at the manganese-rich end.' The purpose of this investigation was to measure the vapor pressure of manganese over a series of Cu-Mn alloys and from these values determine the thermodynamic properties of the binary system. Vapor pressure measurements were made in the temperature range 973" to 1273"K, remaining within the solid-solution region for each alloy studied. EXPERIMENTAL PROCEDURE The relative thermodynamic properties of solid Cu-Mn alloys were determined from vapor pressure measurements by means of the Knudsen effusion tech- nique. Several discussions of the theory can be found in the literature. In the case of copper and manganese, it is assumed that manganese is the only component subliming, so the vapor pressure of manganese over the various alloys can be determined directly by measuring the weight loss of the effusion cell. This is a valid assumption since the vapor pressure of manganese is about four orders of magnitude higher than the vapor pressure of copper in the temperature region of interest. The vapor pressure of manganese over the alloys at any given temperature is then related to the weight loss of the effusion cell per unit area per unit time. An upper limit of 1.5 x 10"s has been measured for the ratio of polyatomic to monoatomic molecules for manganese vapor in equilibrium with solid manganese at 1180°K, so it was assumed that manganese vapor is monoatomic. The effusion cells, fabricated from high-purity alumina, are 26 mm high, 18 mm OD, and have a wall thickness of 1 mm. Three different sized holes of 2.03, 2.54, and 3.18 mm diam were drilled in the lids from the inside face to minimize chipping, and the lids were then slip-cast onto the cells to provide a gas-tight seal. Alumina was selected for this particular application both because of its resistance to thermal shock and reaction with manganese vapor. In the ideal case, the orifice of the effusion cell should have a knife edge so that effusion through the orifice

Jan 1, 1970

By AIME AIME

AT A meeting of the Boston Local Section of the Institute, on Oct. 3, approval was voted to the work done by its representatives on the Committee opposing the passage of a bill by the, Massachusetts Legislature to license engineers. The report is as follows: The Joint Committee on Licensing of Engineers, which included a Committee of the Boston Society of Civil Engineers and representatives of seven other societies,* submitted to the members of the respective societies, on Jan. 8, 1921, a report in which it was stated that on Jan. 4, 1921, a petition was filed in the Legislature of Massachusetts by the Boston Chapter of the American Association of Engineers accompanied by a bill to provide for the registration of professional engineers and land surveyors. This report also stated that at a meeting of this committee, held on Jan. 7, 1921, it was voted:

Jan 1, 1921

By C. Land, R. Hultgren

Heat contents of four Cr-Ni alloys were determined in a diphenyl ethev calorimeter. Aside from ferromagnetic effects, Kopp's law of additivity of heat capacities is approximately fol-lowed, in disagreement with earlier results of A. W. Foster. In 1934 Foster1 reported heat-capacity measurements of dilute solutions of chromium in nickel, primarily as a study of the effect of alloying on the ferromagnetic Curie temperature. He found that, apart from the Curie temperature effect, the general level of heat capacities was reduced 10 pct by the addition of 1 pct Cr; 20 pct by the addition of 2 pct Cr. His measurements of pure nickel essentially agreed with accepted values. These results indicate that small amounts of dissolved chromium cause an increase in the Debye temperature of nickel, presupposing a change of frequency of interatomic bonding vibrations which is much larger than should be expected. If Foster's results were verified, therefore, they would have important implications for bonding theory. The only other heat-capacity measurements in this system seem to be those of Taylor and Hinton,' who studied anomalies which they attributed to super-lattice formation at 25 at. pct Cr. At temperatures above the anomaly, Taylor and Hinton found heat capacities at this composition were quite normal, approximately obeying Kopp's law of additivity. EXPERIMENTAL WORK In order to verify or disprove the remarkable results of Foster, the heat contents of four dilute solid solutions of chromiunn in nickel were measured in a diphenyl ether calorimeter. This instrument, described elsewhere,, operates on the principle of the Bunsen ice calorimeter, but uses diphenyl ether as the working substance. Diphenyl ether melts at the convenient temperature of 26.S°C and supplies a more sensitive measure of heat than ice. The hot sample, in an atmosphere of argon, is dropped from a furnace at a measured temperature into a chamber which is surrounded by a mixture of solid and liquid diphenyl ether. The heat from the hot specimen melts some of the solid without chang- ing the temperature of the calorimeter. The amount of solid melted, and therefore the number of calories released by the specimen, is measured from the increase of volume of the mixture, which pushes mercury down a graduated capillary tube. The apparatus has been standardized against the known heat content of pure platinum. Heat loss during the dropping of the specimen was estimated by comparing the heat content of an empty platinum capsule with a solid platinum ball of the same radius and degree of polish of the surface. Repeated tests demonstrate the precision of measurement to be closer than *0.3 pct. Smoothed experimental results are listed in Table I. The tabulated values for pure nickel are taken from kelley, several measurements were made which agreed closely with this tabulation. For chromium, however, no similar agreement was found. The values tabulated were taken from a thorough study of chromium with the diphenyl ether calorimeter which will be published elsewhere.= Suitable plots of the data showed the expected ferromagnetic anomalies in the low-chromium alloys, while the 11 pct alloy shows no ferromagnetic anomaly, but a different, small anomaly below 900°K. This is perhaps the same anomaly found in CrNi, which was once attributed to superlattice formation,' but is probably due to some other cause, such as antifer-

Jan 1, 1960

By Thunaes, Arvid

Pilot plant test work in 1942 and 1943 showed that by a combination of desliming, fine-size classification, and Sullivan deck concentration it is possible to recover heavy minerals such as cassiterite at least as fine as 10 microns in size. This appreciable improvement in gravity concentration practice has been substantiated by several full-sized plants.

Jan 1, 1950