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In connection with the presentation of his paper in oral abstract, Mr. Hansell exhibited samples of briquettes, showing their porosity, and the change of surface produced by burning. Alfred H. Cowles, Sewaren, N. J.—I am familiar with this furnace, and I wish to point out that the larger it is, the greater is its efficiency, and the longer its life. In Europe, experiments have been made with small, short furnaces of this character, accommodating narrow cars; whereas Mr. Hansell says that there is in this country a furnace 180 ft. long .and 10 ft wide. The American furnaces, moreover, differ in design from those used in Europe; and we may expect from these larger furnaces not only greater efficiency, but also greater durability —the latter advantage being due to the fact that, in these large furnaces, projecting brick walls of greater thickness can be provided, to prevent the heat from attacking the sides of the cars, by means of bricks which, over-reaching these iron surfaces, furnish a protective cover to them. In other words, in these

Jan 1, 1913

Jan 1, 1934

Jan 1, 1934

Long pipelines handling suspended solids find wide use throughout the mining industry. In phosphate, iron ore, and clay mining; in hydraulic stripping of overburden; in tailing disposal; and in transferring concentrates between plants pipeline transport may prove cheapest material handling method. One drawback is necessity for providing attendance at booster stations, both for control and for protection of pumping equipment from sudden surges and failures. Thiele Kaolin Co. in Georgia has come up with an installation where instrumentation does this job automatically, efficiently, and economically.

Jun 1, 1955

By G. K. Manning, M. C. Udy, L. W. Eastwood

Those who have examined beryllium and beryllium-rich alloys under the microscope have noted the results of the difficulties encountered when preparing these materials for examination. Hard constituents are readily chipped and pulled out of the matrix, and the soft ones are easily gouged out or embedded with abrasive or other material. The matrix is easily deformed, which makes it very difficult to remove the effects of scratches. Furthermore, the matrix and some of the constituents are also readily pitted during etching, which makes the structure difficult to develop. The metallographic techniques designed to avoid these difficulties are neither radically new nor necessarily the best possible procedures. They were developed at Battelle to fill immediate requirements as part of a study of the preparation and pouring of beryllium melts as described in a separate paper. A part of the research program on the causes of gas unsoundness in beryllium castings entailed a study of the effects of such gases or gas formers as oxygen or oxides, nitrogen or nitrides, and carbon or carbides. These gases or gas formers, if dissolved in the melt, might be an important factor in the study of unsoundness caused by gas evolution in beryllium. Because it was necessary to be able to distinguish these gases or gas formers, if present as alloy constituents, from metallic phases also present as alloy constituents, a series of alloys was prepared with additions of the various possible metallic and non-metallic constituent formers. It should be emphasized that the constituents referred to as gases or gas formers are important in the study of gases in beryllium only if they form a part of the alloy, that is, if they dissolve in the liquid or solid metal. During the first part of the development of metallographic techniques, the Massachusetts Institute of Technology, unpublished report (TC 3315, Nov., 1945) by Paul Gordon, describing various microconstituents in beryllium, was quite useful. Of particular interest in this report is the confirmation of one of the conclusions drawn from the present investigation, that is, that a distinct oxide phase apparently does not occur in beryllium. The Preparation of Metallographic Specimens GRINDING PROCEDURE The original specimen is either sawed or cut on an abrasive wheel to a convenient size. For best results, the surface to be polished should not be more than about 1/4 in. square, and it is convenient to mount the specimens in bakelite to facilitate handling. Two alternative grinding procedures have been developed. As one alternative, specimens are ground successively on 120-, 240-, and 400-grit, wet-or-dry metallographic discs. The abrasive discs are revolved at 1750 rpm on a conventional pedestal grinder. The coarsest disc (120 grit) is used either wet or dry, and in most instances, it can be eliminated from the procedure. Grinding on the two finer discs (240 and 400 grit) is accompanied by the application of kerosene. The technique consists of holding an oil can, containing kerosene, in one hand and the mounted specimen in the other hand. While the grinding is being done, several drops of kerosene are applied every few seconds close to the center of the disc. Carbon tetrachloride serves at least as well as kerosene as a lubricant; perhaps it is slightly better, but it volatilizes so readily that an additional health hazard is involved. Light oils and water are not satisfactory for the finer grinding operations. The second procedure is perhaps slightly slower than the first and requires a more careful technique, but it eliminates the use of kerosene. The specimen is first ground wet on a 240-grit disc, followed by dry grinding on a 400-grit disc. Finer grinding does not appear to be necessary with either of the two alternative procedures. The pressures used throughout either grinding operation must be extremely light, that is, barely sufficient to hold the specimen in contact with the disc; otherwise, flow and chipping are almost certain to occur. In both procedures, it is essential that the discs be sharp and that they be discarded as they show evidence of becoming dull or loaded. In general, not more than four or five specimens can be ground on a disc before the disc becomes dull enough to warrant discarding it.

Jan 1, 1950

One of the results of the work of the Committee on Precious and Base Metals is that the present Bulletin is as large as some of. the annual volumes of Transactions of the Institute, and we extend our. compliments and thanks to the Committee and express to the members thereof and to. the authors, who have so bounteously given of their time and information, the. sincere gratitude of the Institute. In order to get all these papers printed and distributed to the membership in advance of the meeting, it was necessary to divide the work between two printers. This accounts for the discrepancy in the pagination of the Bulletin; and we also ask the indulgence of our readers in case errors have crept into this preliminary edition during the period of unusual pressure. Program of the Butte Meeting.-The program of the Butte meeting will include six technical sessions for the presentation and discussion of papers and five half-clay visits to mines and metallurgical works. The following program is practically in final form, with slight additions which may be necessary later. Every effort will be made to have papers presented and discussed on scheduled time, so that members who are unable to attend the entire meeting may so plan their trip as to hear and discuss papers in which they are especially interested.

Jan 8, 1913

Howe Memorial Lecture The Howe Memorial Lecture, in memory of Henry Marion Howe, Past President of the Institute, was authorized in April, 1923, as an annual address to be delivered by invitation under the auspices of the Institute by an individual of recognized and outstanding attainment in the science and -practice of iron and steel metallurgy- or-metallography, chosen -by-the Board-of Directors upon recommendation of the Iron and Steel Division. The following were the Howe lectures and lecturers for the years indicated 1924 What is Steel'., By Albert Sauveur.

Jan 1, 1938

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Jan 1, 1907

By Henry G. Morris

The use of compressed air for the transmission of power has reached so great a development that we find numerous large establishments devoted to the manufacture of machinery for its production and application, and special periodicals published for the dissemination of information on the subject. Moreover, its employment is so general in mining operations that no apology is needed for the presentation to the Institute of such a paper as the present. The admirable articles of Mr. E. A. Rix, published in Conzpressed Air, show a wide range in the mechanical efficiency of air-compressors, varying, under different conditions, from 15 to 60 per cent.; and it is evident that any

Jan 1, 1902

W. H. PORTH, New York, N.Y.-I would like to ask what effect segregation of lead would have upon the corrosion of sheet zinc; also what effect would abnormal percentages of iron have upon the ductility of Sheet zinc? One of our difficulties seemed to be that the cells, when standing on the shelf, corroded. We have attributed this to local action in the zinc sheet. We would like to know whether the segregation of, these impurities in this sheet zinc will have any effect on the local action occur-ring in sheet zinc. Lately we have had difficulty in punching some sheet zinc, in that the sheets split in the die. The section that split seemed to have an abnormallly high percentage of cadmium and iron; would that cause it to become brittle? C. H. MATHEWSON.-Iron is one of the most unwelcome impurities when high ductility is the principal requirement in rolled zinc. High

Jan 12, 1919

Since this paper was written, some changes have taken place, materially reducing the cost of iron-making as estimated in the text. These are chiefly reductions in the prices of ore and fuel. The charcoal used is now made in bee-hive ovens, and the price is con-

Jan 1, 1895

By ROBERT B. COONS

SELECTIVE SERVICE must meet three important demands for man power: (1) Activities concerned with production of war goods. (2) The armed forces. (3) Civilian activities and institutions the continuance of which are essential to maintaining the structure of our American democracy. In the above enumeration of demands I have placed everything, including most of our most prized possessions and activities, after the demand for men for war production and the armed forces. To establish an order between the latter two is difficult. For the time being, at least, the Selective Service policy is to make sure that we avoid the risk of "too little and too late." No soldier, sailor, or marine should be sent from these shores to risk his life without the assurance of having a gun, clothes, food, and medical supplies. Therefore, the premium is now being placed on man power for war production and in our process of selection no stone is left unturned to see that our agencies are fully informed of the needs of war production. Our procedures set up recourses for employers of war-production man power so that their activities need not be disrupted, at least not until they have had time to train replacements.

Jan 1, 1942

By Oscar A. Glaeser

INDUSTRIAL relations in the United States Smelting Refining and Mining Company's Western operations covers the field of personnel and labor relations, and the principal aims are to render service to the employes of the Company and to its operating departments. Accident prevention Safety is a primary function. A safety engineer is employed at each operation. The wholehearted support of Company officials, staff, and the working force has been most successful in preventing accidents. Constant vigilance has been combined with a policy of building safety into all operating activities whether these are in the construction of a new facility, the developmnt of a mining system, or the direction of the working force. That this policy has produced results is attested to by the fact that the accident frequency rate at the Company's major mining operations in Utah has been reduced approximately 75 per cent in the ten-year period ending Dec. 31. 1946.

Jan 1, 1948

Jan 1, 1913

Jan 1, 1944

Jan 1, 1944

Jan 1, 1925

A. 0. ASHMAN, Palmerton, Pa. (written discussion *.).-Mr. Newcomb's paper has interested me greatly, as I have had numerous experiences along this line. I do not think enough emphasis can be put on his warn-ing to keep platinum couples free from contact with quartz tubes, as silica shows a tendency to alloy with platinum to a surprising degree even at low temperatures. I have frequently had evidence of silica contamination in a perfectly good tube, in which there was seemingly no possibility of a reducing atmosphere. This is rather important as it seems to be common practice to insulate, as well as protect, the wires by means of- capillary silica tubing, thus allowing the entire wire to be in contact with the silica. The best way to mount a couple in a silica protecting tube is by means of double-bore porcelain insulating tubes, the protecting tube being slightly longer than the couple so as to leave a space between the couple and the end of the tube. In this way there is no possibility of contamination from silica. In no case should silica capillary tubes be used to insulate platinum wires. Mr. Newcomb states that there is still much to be desired in pyro-meter protecting tubes; this is in keeping with my experience. From a practical standpoint there is not a satisfactory pyrometer tube on the market for high temperatures; with all clue respect to the many improve-ments and good work recently done in this line. I believe that the whole future development of pyrometry is dependent on the development of suitable refractories. With suitable refractories, for example, Darling's1 work with liquid couples could be developed to a practical basis, making possible the use of base-metal couples to replace platinum.

Jan 12, 1919

Jan 1, 1946