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By J. Burns Read, S. Tour

It is the purpose of this paper to summarize, as far as possible, the metallurgical information and experience gained by the Ordnancc Department, during the war, in the manufacture of artillery cartridge cases, to describe the tests to which artillery cartridge cases were put, and to summarize the knowledge and experience gained in this testing. The authors wish to acknowledge the aid given by manufacturers, army officers, and civilian employees of the Department in obtaining data. Artillery cartridge cases are cold drawn from circular disks punched from strips of rolled brass. The rnanufacture involves from 25 to 30 main operations, which are done almost entirely on a punch press. Descriptions of the operations have appeared in various periodical:: and, therefore, will not he given here. After each cupping, or drawing, operation, except the last, the cases are annealed at from 540" to 650" C. (1000" to 1200°F.), to remove all the hardening stresses set up in the metal and to allow complete recrystallization. After each annealing, the cases are pickled in niter cake or sulfuric-acid solution and then washed in water to remove all traces of acid. In some instances, the cases arc then immersed in a cyanide-salt solution, and afterwards rinsed in water, to remove the thin layer of copper that forms on the surface of the cases during the acid pickle. The last cold-drawing operation is followcd by the heading operation which, by flattening the head of the case on the outside, causes the metal to flow on the inside to approximately the proper finished dimensions. The mouth, or open end, is then annealed at 430" to 450" ('. 1800" to 900" F.) by immersion in a salt bath or by gas flames. After being washed, the eases are tapered, when they arc ready for machining, inspection, and testing. Cartridge-case Disks Good disks of proper composition and physical properties are essential to the production of good cartridge cases. The Ordnance Department

Jan 1, 1923

By J. Burns Read, S. Tour

It is the purpose of this paper to summarize, as far as possible, the metallurgical information and experience gained by the Ordnancc Department, during the war, in the manufacture of artillery cartridge cases, to describe the tests to which artillery cartridge cases were put, and to summarize the knowledge and experience gained in this testing. The authors wish to acknowledge the aid given by manufacturers, army officers, and civilian employees of the Department in obtaining data. Artillery cartridge cases are cold drawn from circular disks punched from strips of rolled brass. The rnanufacture involves from 25 to 30 main operations, which are done almost entirely on a punch press. Descriptions of the operations have appeared in various periodical:: and, therefore, will not he given here. After each cupping, or drawing, operation, except the last, the cases are annealed at from 540" to 650" C. (1000" to 1200°F.), to remove all the hardening stresses set up in the metal and to allow complete recrystallization. After each annealing, the cases are pickled in niter cake or sulfuric-acid solution and then washed in water to remove all traces of acid. In some instances, the cases arc then immersed in a cyanide-salt solution, and afterwards rinsed in water, to remove the thin layer of copper that forms on the surface of the cases during the acid pickle. The last cold-drawing operation is followcd by the heading operation which, by flattening the head of the case on the outside, causes the metal to flow on the inside to approximately the proper finished dimensions. The mouth, or open end, is then annealed at 430" to 450" ('. 1800" to 900" F.) by immersion in a salt bath or by gas flames. After being washed, the eases are tapered, when they arc ready for machining, inspection, and testing. Cartridge-case Disks Good disks of proper composition and physical properties are essential to the production of good cartridge cases. The Ordnance Department

Jan 1, 1923

By E. E. Bach

The administration of industrial organization today embraces more than the cost of production and selling prices. Competition is deeper seated than mechanical devices, overhead charges, and a shrewd manipulation of the markets. Despite the " down-to-the-minute " equipment and the "last word in organization," it is quite evident that "capacity production" will be an unknown quantity until the workman is considered as a producer, in relation to his home, as he is now considered in relation to industry. Whether or not a man shall do an honest day's work is as much a psychological condition as it is a matter of physical strength or skill. His attitude toward his work each morning is determined, to a large degree, by the environment of his home. Whether this attitude, good or bad, obtains the day through will depend entirely upon the one fact as to whether the corporation which employs him does or does not differentiate between the mechanical factor and the human factor in industry. To be more specific, sociological work, under whatever name, should be of such a character as to influence the life of a workman in such a manner as to establish a cooperative interest in his work, foster within him a spirit of contentment in his home, lead him so to employ his leisure time that he will not lower his efficiency as a workman, destroy his domestic happiness, or endanger his standing in the community as a citizen. While no fixed rules of procedure can well be formulated for the development of the work, yet definite lines of activities will readily present themselves as applicable to the individual needs of a community. This is especially true where community influences and agencies pertaining to general welfare are easily correlated. Any definite work attempted must be determined by the type of the

Jan 1, 1918

By J. Gordon Parr, G. R. Purdy

The phase boundaries of "TiNi" have been accurately determined by high-tewperature X-ray diffraction and metallo-graphic techniques. The phase (centered at 51 pct Ni) has a restricted range of homogeneity at 500°C, and a much greater range at 800°C. "TiNi" in all alloys containing less than 51 pct Ni decomposes rapidly and reversibly at 36°C to form a previously unreported phase. ThE region of the titanium nickel system corresponding to the phase "TiNi" has been the subject of several investigations.1,2,4-7 Laves and wallbaum1 reported "TiNi" as a body-centered cubic (a2) Phase, and Duwez and Taylor2 determined its para- meter to be 2.986. Duwez and Taylor also reported that "TiNi" decomposed into "Ti2Ni" and "TiNi3" on prolonged heating at 650" and 800°C, which led McQuillan3 to suggest a sluggish eutectoid reaction between "TiNis" and "Ti2Ni". Margolin, Ence, and Nielsen,' working with higher purity alloys, found no evidence of this decomposition. They showed the "TiNi" phase region extending from 49 to 54 pct*

Jan 1, 1962

By L. A. White

IN this paper it is proposed to follow the developments in the design of the lead blast furnace at Port Pirie from the time The Broken Hill Associated Smelters Pty. assumed control in 1915 to the present time, with special reference to the development of the system using two superimposed rows of tuyeres as is now in operation. Lead smelting operations first commenced in 1889, when the British Broken Hill Pty. Ltd. started its first furnace. This was followed by installing two more furnaces during the same year and another the following year. In 1892, Broken Hill Proprietary Co. Ltd. acquired the smelting works and combined operations with those at Broken Hill, New South Wales; by 1897, the whole of the smelting operations had been transferred to Port Pirie and thirteen blast furnaces were built to treat the Broken Hill ore production. In 1915, The Broken Hill Associated Smelters Pty. Ltd. took over from the Broken Hill Proprietary and have carried out operations since that time. From its inception, the present company started on a long range program of reconstruction, in which the development of the lead blast furnace has played a prominent part. A definite trend in plant development has been towards the simplification of plant control by a reduction in the number of operating units. The great advantages of technical control which resulted from the very simplified flowsheet established in the continuous refining process stimulated the desire to extend the principle to the smelting operation. Thus in the sequence of furnaces described here, it will be noted that the trend has been towards larger and, of course, fewer units. With each such development it is significant that the operating conditions and metallurgical results have shown steady improvement. Standard Furnace In 1920 there were seven furnaces operating, five of a type subsequently called the standard furnace and two of the original thirteen smaller furnaces, the latter type being used for the treatment of drosses, etc. produced from the refinery section, while the standard type carried out the main, lead-smelting operations. The standard furnace (figs. 1 and 2) had the dimensions given in table I.

Jan 1, 1951

By J. M. Flaitz, A. S. Parks

OF the various methods of sampling gas-condensate wells, a method that secures a continuous representative sample of the well stream is desirable. Such a method, consisting of a sampling tube introduced into the well tubing, has proved satisfactory. The method is sufficiently accurate for operating and engineering problems. A portable testing apparatus can be used with the sampling tube to obtain data useful in studying the economic and technical aspects of the development and operation of gas-condensate properties. INTRODUCTION The recent discovery and development of gas reserves that contain hydrocarbons that condense with reduction of temperature or pressure, or both, to form a product known as condensate, has brought many new problems to the oil and gas industries. With further discovery of deep, high-pressure fields it is presumable that many more gas fields of this type will be added to the steadily increasing number. Such gas reserves are found either associated with oil as a gas cap or in separate formations. There seems to be no positive correlation between the physical or geological nature of the reservoir, and the chemical composition or phase characteristics of its contents. Knowledge of the chemical make-up and phase behavior of gas-condensate reserves are needed to cope with many problems. A knowledge of the chemical composition and phase characteristics of the reservoir material is necessary to properly design a gasoline or recycling plant, to estimate natural gas and condensate reserves, to enable the operator to study the economic and technical aspects of various methods of operation and development, and to carry out the plan of operating subsurface and surface lease equipment. This information is often useful in questions of mineral ownership, proration, legal position, and taxation. It is the purpose of this paper to discuss methods used by the writers to determine the chemical composition and phase characteristics of the fluids produced from a condensate well. The scope of the paper includes a discussion and description of the method of sampling, the results of tests on the accuracy of the sampling method, a description of a portable testing apparatus used to examine the phase characteristics, typical results of tests on wells from several condensate fields, and some of the applications of these data to production problems. References to previous work on this subject are cited at the end of the paper. THE PROBLEM At reservoir conditions of temperature and pressure, the fluids produced from a condensate well exist in a homogeneous vaporous condition. The consequent reduction of temperature and pressure that occurs as this gas enters and flows up the well tube results in condensation of some of the hydrocarbon material to form a liquid. The relative amount of liquid condensed at any point in the flowing system

Jan 1, 1941

By Gilbert Soler

Page Introduction. By Gilbert Soler.........................657 Deoxidation of Basic Open-hearth Steel. By T. S. Washburn.............658 Slag-metal-oxygen Relationships in the Basic Open-hearth and Electric Processes. By J. S. Marsh. (With discussion)...........................672 The Total Oxygen Content of Plain Carbon Open-hearth Steel during Deoxidation and Teeming. By Michael Tenenbaum and C. C. Brown. (With discussion)......685 The Occurrence of Oxygen in Liquid Open-hearth Steel—Sampling Methods. By T. E. Brower and B. b. Larsen..........................712 Effect of Deoxidation on the Strain-sensitivity of Low-carbon Steels. By H. K. Work and G. H. Enzian. (With discussion)........................723 The Relation among Aluminum, Sulphur, and Grain Size. By C. E. Sims.......734 Some of the papers and discussions that appear on the following pages were presented at the meeting of the Iron and Steel Division in Cleveland, Ohio, on Wednesday, October 18, 1944. with L. F. Reinartz and H. K. Work as Chairmen; the remainder were scheduled for the New York Meeting of the Institute in February 1945, which was canceled.

Jan 1, 1945

R. W. NEWCOMB, New York, N. Y. (written discussion*).-0n page 1712, the middle paragraph states that, in industrial equipment, only the single-step method of automatic regulation has been applied. Quite recently, there has been developed an automatic temperature regulator, operating in conjunction with a pyrometer of the thermoelectric type, in which the control is a slow regulation, with a range capable of regulat-ing valves, dampers, rheostats, or any other rotatable member, through one or more complete revolutions. It can control two valves at the same time, with a fixed definite ratio between them. Aside from those conditions in which it is. necessary to control two valves with a definite ratio one to the other, the greatest advantage that this slow, even control will have over those controls that are either all on or all off, will be for use in connection with processes where a large temperature variation is required, extended over a considerable period of time; that is, where the temperature must be regulated along an in-creasing or decreasing time-temperature curve.

Jan 12, 1919

S. F. EMMONS RESEARCH FELLOWSHIP. The movement was started by a number of the friends and admirers of the late S. F. Emmons, Economic Geologist of the United States Geological Survey, to perpetuate his name through a fellowship to be known as the " S. F. Emmons Research Fellowship," and they have succeeded in raising some $13,000 for the purpose of carrying on research work in economic geology. The Committee in charge of this Memorial Fund has succeeded in obtaining the co-operation of Professors Kemp, of Columbia, Irving, of Yale, and Lindgren, of Massachusetts Institute of Technology, in the administration of this fellowship. These three gentlemen are respectively geologists of the institutions mentioned and are exceptionally qualified to determine in what direction the fund can be best administered. It is hoped that additional contributions will be forthcoming from many who have heard of this movement. Subscriptions are invited and may be sent to any one of these gentlemen, or to Benjamin B. Lawrence, Treasurer, No. 60 Wall Street, New York City.

Jan 11, 1913

By S. J. Aparo

After surveying the beneficiation techniques in the Florida phosphate field, it is apparent that optimum beneficiation of this ore is a difficult task. Due to continually changing grade, size distribution and basic nature of the ore, there appears to be no universal technique nor a single reagent entirely satisfactory for achieving optimum metallurgy under these dynamic conditions. Although no major change in the basic flow sheet has been made in the last 20 years, there have been many refinements of the process in recent years which have helped increase production, improve recovery, lower unit cost of operation and make the beneficiation of lower grade deposits economically feasible. Among the significant changes is the use of larger plants and equipment which has helped to increase production significantly. The use of cyclones has facilitated and reduced the cost of slimes removal in these large plants. There have also been several new approaches to the flotation of coarse phosphate that are mentioned in the text of this paper. Lastly, significant improvements have also taken place in the area of flotation reagents.

Jan 1, 1970

By R. J. Marcotte, C. T. Eddy, R. J. Smith

The objectives of the investigation herein reported were to determine: (I) the S-curves for certain selected cast steels, (2) whether or not the published S-curves for wrought steels are satisfactory for use on cast steels of similar composition, and (3) to prepare hardenability curves of the selected cast steels. In order to make the final comparisons between cast and wrought steel more completely tangible, it was deemed advisable not only to determine S-curves for the steels submitted in the cast condition but also to roll some of the cast-steel test bars and determine comparison S-curves on such wrought material. This procedure eliminates the composition variable and makes it possible to reveal the differences resulting from plastic deformation of the cast structure in addition to providing the comparison with published data on wrought steels. Cast Steels The cast steels selected for the preparation of S-curves, or time-temperature transformation curves, were similar to S.A.E. series 1030, 2330, 4130 and 4330. Of these the 1030 was supplied by The Crucible Steel Casting Co., Cleveland, Ohio, and the other three by The Sawbrook Steel Castings Co., Lockland, Ohio. The steels were furnished in the as-cast condition. The manufacturers supplied the chemical analyses and the properties that could be obtained in the heat-treated condition—all of which is summarized in Table I. The metallographic and dilatometric procedures and equipment were in general standard. The specific technique employed was described in a report of the Steel

Jan 1, 1945

By M. A. Steinberg, J. Wulff, R. Kamm

In a previous paper1 from this laboratory, the development of a lead grid method for exploring the distribution of strain and density within metal powder compacts was described. In that work thin lead foil with rectangular holes cut at regular intervals was inserted with the powder fill, the arrangement pressed and then radiographed to permit measurement of the deformation of the lead grid. Densities at each grid element obtained in this manner were plotted as a function of the die dimensions. From such plots it was found that the densest part of a compact pressed from one side (the top) is at the top outer region and the least dense at the bottom outer region of the specimen. The axial density maximum occurs more often nearer the bottom than at the top. As a result of such exploratory measurements, it appeared reasonable to conclude that variations in density could be attributed in the main to die wall friction. Thus compacts of large diameter appeared relatively uniform in density except where the die fill had been uneven. Finally it was found that lubrication of the finely finished die cavity contributed more to magnitude and uniformity of density within the compact than interparticle lubrication. Since publication of the above results, it was found that circular-hole grids could be more accurately made and, when deformed within the powder, more readily measured and analyzed. Much of the former work was repeated and new results which include the effect of lubrication, compact height, pressure, speed of pressing and vacuum pressing are reported in the present paper. Circular-hole Grids and Analyses OF Radiographs Commercial lead sheet 0.008 in. in thickness was used in all the work reported. The 0.0938-in. diam holes were punched in the sheet on 1/8-in. centers to an accuracy of 0.001 in. The finished grid used contained eight or more holes in a row and from I to 24 rows. The lead sheet was clamped between two pairs of brass strips bolted to a small milling machine table which was itself bolted to a bench in correct position near a vise which held the punch. Travel of the lead grid in two dimensions was controlled by two steel lead screws calibrated in 0.001-in. divisions. A stripper plate was used on the punch to avoid distortion of the lead foil. A high carbon-high chromium (chrocar) one-piece steel die was used throughout the work. The die cavity was 1.125 in. in diam and the clearance between plungers and die wall was 0.001 in. The die was also used for pressing from both ends with two long plungers. Finally, lapping of die and plungers gave a surface whose rms value On an Abbot profilometer was 5 micro-in. The die walls and plungers were, except where otherwise noted, lubricated with a stearic acid suspension in benzene. This was put on in multiple layers and allowed to dry before filling the die.

Jan 1, 1949

By Hubert O. DeBeck

The following descriptions and explanations apply specifically to the use of the Hotchkiss Superdip, but there are no apparent reasons why they should not apply to any magnetometer. This paper is a product of work in the practical field for several years with the Hotchkiss magnetometer, mostly on mineral deposits in the southeastern United States. The paper describes the result of an attempt to develop a practical and economical field method that approaches, as nearly as possible, the utmost accuracy of which the magnetometer is capable. As there are many published descriptions of various magnetometers and magnetic methods, it would be superfluous to describe such instruments here, but a limited bibliography on the Hotchkiss and Askania magnetometers is appended. The Hotchkiss and the vertical Askania magnetometers have, respectively, maximum sensitivities of approximately 5 and 30 gamma per instrument scale division. Purpose of New Method The purpose of the method described in the following paragraphs is to eliminate, as far as possible, all corrections of field data that cause complexities and inaccuracies in the results of magnetometer surveys. Magnetometer field observations must be corrected for periodic variations in the intensity of the earth's magnetic field, as well as for temperature variations, both of which take place during the course of a day. These variations do not seriously handicap magnetometer work on highly magnetic deposits, but it is impossible to obtain accurate results, by the conventional methods in use today, over weakly magnetic or diamagnetic deposits. This is due to the physical inability to obtain by such methods sufficiently accurate data in the field to make dependable corrections. The magnitude of the necessary corrections of field observations frequently exceeds the magnitude of local magnetic anomalies obtained over various types of mineral deposits. Therefore if these corrections are neglected or made on the basis of inaccurate data, the entire magnetic picture of the area concerned is at least distorted, and perhaps destroyed altogethcr.

Jan 1, 1934

By C. H. Benedict, H. C. Kenny

A 2000-ton ammonia leaching plant has been operated by the Calumet & Hecla Mining Co., at Lake Linden, Mich., continuousl~ since February, 1917, except from April, 1921, to April, 1922, during the period of depression following the European war. A description of this plant has been published elsewhere.1 The present article describes the operation of the plant since 1917, together with the changes in the process that have been found to be advisable. In spite of the fact that this plant and that of the Kennecott Copper Co. are the only ones operating on a large scale, much experimental work is being done on ammonia leaching, as applied to oxidized ores, and it is to aid these and other investigators that this detailed account is given. For the benefit of those unfamiliar with the original article, the following short abstract is given, as an introduction to a more detailed account of the process and the reasons for present practice. Rêsumê of Previous Article Leaching on a commercial scale began in July, 1916, and by Februsry, 1917, the plant of 2000 tons capacity was in commission. The ore treated is a conglomerate containing native copper and no sulfides or oxidized copper minerals. Before leaching, the ore is crushed by steam stamps and Hardinge pebble mills to pass a 28-mesh screen. Free copper is removed, by gravity concentration, on Woodbury jigs and Wilfley tables, and colloidal slime for oil flotation is removed by quadruplex Dorr classifiers. The leaching sand remaining contains about 2 per cent. + 28-mesh material and 15 per cent. — 200-mesh and carries from 8 to 14 lb. of copper per ton, depending on the grade of ore worked. The solvent employed in leaching is a water solution of ammonium carbonate,

Jan 1, 1924

By Ralph Sweetser

PROGRESS in blast-furnace practice during 1922 has been in the direction pointed out in my article in the March, 1922, issue of MINING AND METAL-LURGY; this advance has been very satisfactory in spite of the difficulties caused by the great coal strike and the railroad strike. The progress, especially in increased tonnage, has been brought about, not by increasing the size of the furnaces, not by improved mechanical devices, but through the application of better blast-furnace practice; the advance has been metallurgical rather than mechanical. The increase in production per stack, has been more pronounced than in any period since the time that James Gayley began to break blast-furnace records in Pittsburgh. These big tonnages have been made in furnaces designed to make 550 to 600 tons of pig iron per day; but several such furnaces have had monthly averages of between 700 and 800 tons per day with a corresponding reduction of cost, and a reduction in the number of man-hours of labor per ton of pig iron. During this period there has been a wider acceptance of the fact that satisfactory blast-furnace results are more dependent on coke quality than on any other factor. There has always been much rivalry among blast-furnace men in making new tonnage records, and many schemes have been used for getting out big pro-duction, but the blast-furnace man cannot make the high records all by himself; it is necessary for him to have the cooperation of the entire management, and also the help of the organization that makes his blast-furnace coke. Herman Brassert has said that "there is no blast-furnace practice possible that can wholly overcome the effects of bad coke." In the past; the blast-furnace superintendent has often been under suspicion if he complained about the quality of the coke in times of unsatisfactory blast-furnace results, but it is now conceded that if the quality of the coke is not right, complaints are not necessarily made as an alibi.

Jan 5, 1923

By George H. Ashley

The present critical state of the supply, distribution, and utilization of coal and the necessity for pooling and zoning coals calls renewed attention to the lack of any fully adequate classification of coal. In the past coals have been classified as anthracite, semianthracite, semibitumi-nous, bituminous, subbituminous coals, and lignite, and a few special types, such as splint coal and cannel coal. But under the term bituminous coal are included a great variety of coals differing markedly both physically and chemically. The term subbituminous coal covers as great a range of chemical differences. In order to distinguish these varieties of bituminous coals it has been customary to designate coal by names derived from the place where mined, or by the name of the bed from which it is mined. Thus, in the market reports, coals are quoted as Pocahontas coal, New River or Sewell coal, Moshannon coal, Ohio coal, Williamson County coal, Jellico coal, and so on indefinitely, no limit being set as to the boundaries of the area to which a given name is applied. Nor is there any scale by which the coal from one place may be compared with the coal from some other district or some other bed. On the one hand, coals from the same district may be quite distinct and sell at very different prices or coal from the same bed may differ greatly in different districts; on the other hand, coals from different states may be so similar physically and chemically that one could replace the other in practical use without any appreciable difference in service. The following classification, arrived at after a careful review of a large number of systems of classification and of all of the recognized characteristics of coal, brings together all coals that so nearly resemble each other physically, chemically, and in heating qualities that any coal of a given type could replace any other coal of the same type and grade in use. Thus, if coals A and B are classed as of the same type and grade they have, so far as known to the writer, approximately the same heating value when burned under the same conditions, and the same character, length of flame, and properties affecting transportation and stocking; and if of the same grade, approximately the same percentage of impurities.

Jan 1, 1920

By John A. Church

In May, 1878, I had the honor of presenting to the Institute, at the Chattanooga meeting, some observations upon the heat of the Comstock Lode, and since then the subject has attracted some attention and criticism, in the course of which, L have observed errors of apprehension which I beg leave to correct now. Mr. John Arthur Phillips discussed it before the Geological Society, his paper being printed in the Quarterly Journal for August, 1879." His criticism is based upon that part of my paper in which I quote a number of analyses of the mine waters, to illustrate the fact that the heat does not come from the oxidation of pyrite. I pointed out that these waters contain only an insignificant proportion of sulphuric acid, and not enough to account for even one per cent. Of

Jan 1, 1880

By K. Barron

The glass insert stressmeter, or photoelastic stressmeter, is an instrument designed to determine stress changes occurring in rocks. It has several potential advantages over other such devices in that it is a biaxial device, it is simple and it is cheap to make. The object of this study was to assess the behaviour of the meter under biaxial loads and to examine some of the problems associated with measurement and interpretation of the fringe pattern. This assessment has been carried out by comparing theoretical and laboratory behaviour of the meter. It has been shown that: a) There are certain optimum measuring points in the meter at which measurements should be made for best accuracy. The position of the points depends on the ratio, n, of the biaxial stresses. b) The meter&apos;s sensitivity can be assumed to be independent of the rock modulus E provided that the rock modulus is < 2.5 x 106 psi and not, as previous workers have assumed, if E < 5 x 106 psi. c) There are several methods of separating the principal stresses; some of these are unsatisfactory. A new method is proposed and discussed. d) The meter sensitivity decreases as the ratio of the biaxial stresses approaches unity; the accuracy thus also decreases. e) The axes of symmetry of the fringe pattern give an excellent indication of applied stress direction. f) Laboratory calibrations are in good agreement with theory. The glass insert or photoelastic stressmeter is an instrument designed to determine stress changes occurring in rocks. It has several potential advantages over other such devices in that it is a biaxial device, it is simple and it is cheap to make. This stressmeter has been described in detail.l,2 Basically it is a hollow glass cylinder that has at one end a light source and filters producing circularly polarized light. The glass cylinder and source are grouted into a borehole in rock and the face of the cylinder is viewed through a quarter wave plate and an analyser. If, after installation, a stress change occurs in the rock, then a distinct colored isochro-matic fringe pattern is seen in the meter. The fringe order at any point in the meter can be determined by counting the fringes and measuring the fractional fringe orders by the Tardy compensation method. The relation between the fringe order at any point and the applied stress change can be determined either by calculation or by calibration. The object of this study was to assess the behavior of this stressmeter under biaxial loading conditions and to examine some of the problems of interpretation of the fringe pattern. THEORY Hiramatsu et a14 have determined the stress distribution in a hollow cylindrical inclusion in an elastic host material when subject to uniaxial stress. Using this solution, the biaxial case of stress p in the x direction and stress q in the y direction (Fig. 1) can be solved by superposition. This has been done in Appendix 1. It is shown that the principal stress difference (s1 -s2) at any point (r,?) in the cylinder is given by:

Jan 1, 1965

By W. H. Durrell

DISCOVERY of large iron ore deposits in New Quebec and Labrador is, undoubtedly, one of the outstanding mining events of the twentieth century. To give an idea of size, the present concession is almost equivalent to a strip a mile wide around the earth at the equator. Importance of this iron ore area can best be appreciated by comparison to the famous Mesabi Range. On Mesabi, the area of favorable rock is 110 miles long and from 1 to 5 miles wide, with a, productive zone about 70 miles long. On the con- cessions the area of favorable rock in the Labrador Trough is 225 miles long and from 10 to 60 miles wide. In Quebec-Labrador, exploration already discloses that the productive zone is 90 miles long, with good chances of being extended at both ends. The Mesabi is covered generally by thick over- burden, and the iron ore deposits were found by T- test-pitting and systematic test-drilling. In Labrador and Quebec, most ore has been developed from a few surface deposits, and when it is considered that at least 95 pct of the area is covered by over- burden, and that there remains thousands of square miles of favorable territory still to be explored, it can be seen that the possibilities for developing additional ore are tremendous.

Jan 4, 1954

By L. R. Velho, N. A. D. Parlee, J. Gani

THE unsteady-state type of gas-liquid metal diffusion cell1 has found considerable application.2"4 Cells of this general design can function as steady-state cells if allowed to operate long enough to reach steady state. This report tells of some success in the adaption of this type of cell for steady-state work, using the 0-Ag system in which the mass transfer of the gas "species" is basically controlled by diffusion in the liquid. The gas, e.g-., O2, is maintained in the cell tube&apos;-3 at 1 atm pressure, Fig. 1, by buret and sensitive oil manometer. The gas, after diffusing through the stagnant metal, escapes at the annular metal surface around the tube at a lower constant partial pressure, in this case that of O2 in slowly flowing air, 1 atm.

Jan 1, 1970