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A High-speed Dilatometer and the Transformational Behavior of Six Steels in Cooling. By Arthur L. Christenson, Edward C. Nelson and Clarence E. Jackson. (With discussion).................................606 Dilatometric Studies of the Graphitization of Cast Iron. By N. A. Ziegler. With discussion) 627 An Interferometer Type of Dilatometer and Some Typical Results. By- L. '4. WIlley and W. L. Fink. (With discussion).........................642 The meeting was held in the Pine Room of the Statler Hotel, Cleveland, Ohio, on Tuesday afternoon, October 17, 1944. The chairmen were F. M. Walters, Jr. and Howard Scott. Introduction F. M. Walters, Jr.—The principal advantages of the dilatometric method perhaps are two, as compared with the method of thermal analysis. One is that the dilatometric method can be applied with a large variety of rates of heating and cooling, whereas thermal analysis—that is, the study of the transformational characteristics by means of heat evolution—is limited to the rates of heating and cooling that reveal the evolution of heat. The dilatometer can be used for the study Of reactions at zero rates of heating and cooling; that is, isothermal reactions. As you will hear this afternoon, the rates have been pushed up as far as 500°C. a second. The other advantage is that the dilatometric method shows that a two-phase region is a two-phase region, whereas the thermal analysis merely reveals the temperature at which the rates of heat evolution are greatest.

Jan 1, 1945

By R. E. Sheppard, A. O. Martel

Zinc sinter plant fume is roasted to selectively sulfate the cadmium. Water leaching of the roasted fume recovers about 80% of the contained cadmium and produces solutions containing about 40 grams per liter cadmium and 10 grams per liter zinc. The solution is treated with sodium bichromate for lead removal. Cadmium sponge, precipitated with zinc dust, is briquetted, melted, and cast into commercial shapes. The residue from the water leach is acid leached with waste acid, solubilizing the zinc and residual cadmium. Impure cadmium sponge, precipitated with zinc dust, is separated from solution with cyclones and dewatered in a centrifuge. Air-oxidation- acid leaching of the impure sponge resolubilizes the cadmium. The resulting solution is neutralized, clarified, and treated for cadmium recovery with the water leach solution. The residue from the leached fume is water-washed and recovered in a centrifuge-thickener circuit. This residue contains lead sulfate and significant quantities of gold and silver. Manpower requirements are held to a minimum by automating operations within the Leach Plant.

Jan 1, 1973

News has just been received that Flight Commander William T. Hall, a Junior Member of-the Institute, was killed in action on Saturday, May 19, 1917. According to the' Toronto Star, Commander Hall was 24 years of age, a native of Toronto, and a grandson of the late William Kersteman. During the four years of his course in mining at the School of Practical Science, Toronto University, he passed every examination with honors. When war was first declared Commander Hall endeavored to join the artillery as an officer, and for that purpose secured a provisional lieu- tenancy with a Hamilton battery, but he did not receive an overseas appointment, and on being graduated as a mining engineer in 1915, he was offered a position in Chile, which he accepted. He left Toronto on May 27, 1915, and was engaged in Chile as a mining engineer for nearly a year. In the latter part of April, 1916, he decided to offer himself again for service at the front. He crossed the Andes and sailed for Liverpool, where he landed on May 13, 1916. On May 27, 1916, Capt. Hall was given a commission as lieutenant in the Royal Flying Corps. He went to the front on Sept. 1, 1916, and remained there continuously. On April 4, 1917, he was promoted from lieutenant to the rank of flight commander. No details of how Commander Hall came by his death have as yet been received.

Jan 1, 1918

By L. D. Lash, J. R. Ross

Scandium is a pseudo-rare earth which is truly rare and expensive. It has special properties which may make it desirable even at the present price of $2750 per lb. Recently the price was lowered from $5000 per lb which had prevailed since 1952, and it is anticipated that usage will be stimulated because of the lowered price. This metallic element is distributed widely in trace amounts in the rocks of the earth's crust. In addition to micro-amounts found in most uranium ores, concentrations of 50 to 100 ppm have been found in Colorado ferberite ore, lateritic nickel ore, heavy sandstone from Utah, Wyoming, and New Mexico, and various zircon sands and monazites from the western part of the US. Scandium has been found as an essential constituent of very few minerals, the most important being thortveitite, a scandium silicate. At the present time, this mineral commands a price more than twice that of gold.

Jan 8, 1961

By E. H. Rennhack

THE presence of sufficient quantities of the inter- stitial elements, carbon, oxygen, and nitrogen is known to decrease sienificantly the room-temperature impact resistance of titanium. Hydrogen does not appear to affect impact strength unless present

Jan 1, 1959

Maryland was the third state to produce coal, and from the available information a small amount was mined each year after 1888, some of it being used locally but probably the larger portion being floated down the Potomac River. In 1798 some coal was used in the arms plant at Harper's Ferry, and while many of the records of this plant have disappeared, we know the tonnages delivered here from 1818 to 1837, the latter date being five years before the date usually given as the start of shipments. These data are shown in Table 54. In addition, some coal was used in an iron plant above Harper's Ferry, but the amount is not known. All of the coal to these plants came down the river, and for 1826-1830, both inclusive, some old canal records show coal passing through the canal at Great Falls, but practically all of the Cumberland coal used around Washington prior to 1842 was floated down the Potomac River during high water, and even at those times it was a precarious and dangerous business. After 1842, when the Baltimore & Ohio Railroad reached Cumberland, the records of shipments are unusually complete. The canal was completed to Cumberland in 1850, but its useful life terminated with the Civil War. The production records of this field are the most complete of any of the early coal mining states.

Jan 1, 1942

By Peter J. Conroy, Lewis V. Wade

Old Ben Coal Co. successfully completed the fit longwall panel in Illinois. The panel was mined wing shield supports and was part of a cooperative agreement with the US Bureau of Mines. This paper describes the rock mechanics studies which were performed to monitor: the performance of the supports, the stress changes in the coal and floor, convergence in entries, and caving mechanism of the roof. From this study, maximum support loads were obtained as well as the stress distribution in the panel, floor and adjacent pillars.

Jan 1, 1981

By W. T. Nightingale

The three gas-producing "pools" discussed in this paper are in Sweet-water County, southwest Wyoming, and Moffat, County, northwest Colorado. Hiawatha, North Baxter Basin and South Baxter Basin gas fields became economically important in 1929 when a 330-mile gas line connected them with Salt Lake City, Ogden and towns en route. This development immediately focussed attention on the gas-producing fields and the efforts of the producing company to develop them in an orderly, economical manner. Several outstanding interests were acquired and working agreements made with others. Thus the interference of natural drainage areas was avoided, the pernicious practice of drilling direct

Jan 1, 1930

By T. A. Kauppila, V. Rajaram, R. L. Bolmer

With steadily increasing prices for imported oil, commercial production of oil from oil shale can become a reality in the near future. Presently we are importing about 43% of our oil needs and this reliance on foreign oil can be reduced by utilizing the vast resources of oil shale in the western US. The oil shale resources in Colorado, Utah, and Wyoming, averaging 0.06 m3/ton (15 gal per st) and occurring in beds at least 3 m (10 ft) thick, are estimated at 293 Gm3 (1842 billion bbl) of which only 97 Gdm3 (610 billion bbl) are recoverable with current technology. The full potential of this vast resource can be realized only if significant steps are taken toward improving mining and retorting technology and solving environmental problems. Oil shales with a grade of 0.08-0.10 m3/ton (20-25 gal per st) are amenable to mining and surface retorting; whereas lower-grade oil shales may be recovered by in situ retorting.

Jan 4, 1978

By E. C. Herkenhoff

THIS subject may be controversial. Personal preferences influence the final selection of cyclones, and side issues such as costs, floor areas, head room, and ease of replacing worn parts all enter the picture, but the following comments and data should apply to most cyclone selection problems. Broadly, the uses for cyclones in wet classification may be divided into three fields: 1) Open circuit operation, for two products, in which feed rate and sizing vary and the products vary. For example, feed may be divided into a sand product and a slime product. 2) Open circuit operation, for two products, in which feed varies, one product to have constant sizing. This calls for adjustment in either the apex or the vortex aperture. 3) Closed circuit operation, the finished product to have constant sizing. Most classification jobs fall in this category.

Jan 8, 1957

The library of the above-named Societies is open from 9 A.M. to 10, P.M. except on holidays. It contains about 70,000 volumes and 90,000 pamphlets, including sets of technical periodicals and publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library, through its Library Service Bureau, can render valuable service through correspondence; letters requesting information will receive especial attention: The Library is prepared to furnish references and photographic copies of articles on mining and metallurgical subjects; to determine the existence of mining maps, and to furnish general information on the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape.

Jan 9, 1918

By Oliver B. Hopkins

During the year 1936, a new high record was established for Peruvian production, the total amounting to 17,594,689 bbl., which brought the cumulative production of the country up to 205 million barrels. The 1936 figure represents an increase of 530,288 bbl. over that of 1935. The property of the International Petroleum Co. contributed 369,577 bbl. of this increase and the Lobitos property 158,233. Exploration work in the country was continued. The Selden Breck Co. examined a strip of the National Reserve in eastern Peru from Tambo del Sur to the Rio Pachitea. This company was granted a concession for a term of four years embracing approximately 50,000 acres near the confluence of the Rio Pachitea and the Rio Ucayali. During the year, the Peruvian Government commenced drilling a well on one of the reserved zones at Zorritos. At the end of the year, this well had reached a depth of 1300 feet. La Rrea-Parinas Estate.—Production on the La Brea-Parinas Estate of the International Petroleum Company, Ltd., reached an all-time high in 1936 of 15,126,491 bbl., an increase of 369,577 bbl. over the 1935 record. The total production from 1890 to 1936 was 163,668,014 barrels.

Jan 1, 1937

WILLIAM YOUNG WESTERVELT, Chairman, Representing A. T. M. E. and M. and M. Soc. of Am. ALFRED G. WHITE, Secretary, Representing U. S. Bureau of Mines. W. 0. HOTCHKISS, Representing Association of American State Geologists. DAVID WHITE, Representing U. S. Geological Survey. The organization and purpose of the War Minerals Committee was explained in a special war notice in the-August Bulletin. The first work of this Committee is to secure and condense information as to the relative importance of different properties from the standpoint of domestic mineral production. When the possibilities of ore deposits are known, involving, in some cases, further examination through the voluntary services of, Engineers and Geologists, then the necessary policy required to stimulate such development can be determined. Proper recommendation has been and will be made to .the various agencies controlling the situation during the war. This will insure a complete presentation of the needs of the situation. Every legitimate effort will be made to stimulate the production of domestic minerals and to put the industries on a permanent basis. The following information forms indicate the type of information required by the Committee. Engineers and Geologists can assist in one of several ways in furnishing information to the War Minerals Committee:

Jan 10, 1917

By Peter N. Calder

This paper deals with the reinforcement of igneous rock slopes at three open pit iron ore trines in northern Canada. The pits involved utilize overall slope angles in excess of 60º with ultimate depths in the order of 250 m. Three case studies are described. The first concerns the reinforcement of a 300,000 Ton undercut rock wedge, approximately 70 m in height. This was accomplished using 20 cm diameter steel bales, installed in 25 cm diameter vertical holes, and a cement-sand grout. The second involves the reinforcement of a 40 m wide diabase dyke which had been continuously failing as the pit deepened. A unique form of rock reinforcement was used in that the entire mass of the undercut dyke was not pinned to the wall. Rather an interlocking effect between individual blocks within the dyke was relied upon. A third concerns the reinforcement of a berm which was undercut by the contact between the ore and waste. This reinforcement was also accomplished using a combination of steel bales, rods and cement grout.

Jan 1, 1982

By B. Das, V. Hucka

In light of the present energy crisis, coal appears now as the only reliable source of energy. The production of coal is expected to regain a rising trend after the latest slump. Aside from the competitive price with natural gas and oil, the other retarder of coal production is its environmental pollution effect. Gasification of coal has been advanced as the partial solution to the energy-ecology crisis. All the Advantages In situ gasification of coal may be considered a further step in this direction. It carries all the advantages of normal coal gasification as a stable source of energy; it is clean to handle and nonpolluting of the environment. It partially and sometimes fully does away with mining, makes uneconomical low grade coal and lignites economical and places some formerly unworkable seams within the scope of modern technology. The seams posing problems for mining due to tectonic disturbances may be converted into gas in situ. Low grade coals, such as lignites, which otherwise would be left in nature as uneconomic wealth, may be exploited by underground or in situ gasification. Thus, in situ gasification is likely to increase the exploitable reserves of coal and may reduce the cost of production. An additional merit of this method is that coal substance never reaches the surface and there is no problem of cinder disposal.

Jan 8, 1973

Those familiar with the war in France at first hand know that in these last two years the weight of the suffering has fallen upon the families of the well-to-do classes; those who before the war lived in comparative ease and comfort, with every prospect of educating their children as their parents and grandparents had been. Thousands of the men in these families have been killed, "officiers d'élite," and the small pensions accorded the widows permit them only to house and feed their children HELÈNE JOURNÈS. and give them a common-school education. The pension for a lieutenant's widow is $245 a year; for 'a captain's, $345; for a colonel's $575; and so on. At present, it requires three francs a day to provide food for one person in cities, and conditions are not improving. The American Ouvroir Funds, 681 Fifth Ave., New York City, has tried for nearly two years to have individual Americans give individual children a "bourse," or purse, as it is called, of from $150 to $250 a year, so that they may enter such educational institutions as the Lycées, the Polytechnique, Beaux Arts, St. Cyr, etc. The war relief societies of these military schools furnish photographs and histories of children under their care and on their lists.

Jan 12, 1918

By T. P. Oxford, G. Y. Onoda, E. D. Whitney

Disposal of phosphatic clay waste slurry has been a problem since the advent of hydraulic processing of phosphate rock in Florida. Alternatives to the present practice of storing slimes behind earthen dikes have been earnestly sought for more than a quarter of a century. Seepage dewatering is a promising technique intended to increase waste clay solids content to a level sufficiently high to permit clay disposal in mine cuts, in lieu of above-grade impoundment. An experimental array of vertical seepage columns containing mine tailings sand was constructed. Significant improvement in waste clay dewatering relative to that occurring in a control test was observed when approximately 1800 m3 of waste clay was disposed of in the presence of the seepage aids.

Jan 1, 1983

By R. V. Whetsel, V. R. Garfias

It is estimated that during 1936 world consumption of petroleum, its products and related fuels reached an all-time peak of 1,757,778,000 bbl., an increase of 143,000,000 bbl. over 1935. As indicated in Table 1, world output of petroleum and related fuels exceeded demand by 92,510,000 bbl. during the year, as compared to an excess output of 88,000,000 bbl. during 1935. Production within the United States exceeded domestic demand by approximately 51,000,-000 bbl. in 1936, as compared to an excess output of 53,000,000 bbl. in the previous year. Outside the United States, production exceeded demand by 41,510,000 bbl. in 1936 and by 35,000,000 bbl. in 1935, indicating that foreign output is making no progress toward curtailment in line with demand. Table 1 also combines excess production in the United States with the favorable balance of exports over imports, showing that stocks in the United States were reduced by 23,400,000 bbl. in 1936, as compared to 22,447,000 bbl. in the previous year. In the rest of the world, excess output over demand combined with the excess of imports over exports from the United States indicates an unfavorable balance of approximately

Jan 1, 1937

By John Cogan, P. M. Gomez

A typical problem in applied rock mechanics is an accurate prediction of support requirements for deep rock cuts. This paper presents experience with this problem as obtained from excavations for a powerhouse at the Pine Flat Dam near Fresno, California. The project, sponsored by the Kings River Conservation District is still under construction. Highly jointed and weathered rock was discovered during initial excavation. Wedge failures along clay filled joints and bedding planes presented potential support problems. Detailed mapping of joints and beds was undertaken to establish basic patterns of all rock discontinuities including mean orientations and an estimate of orientation variations. Rock bolting patterns were devised to meet these patterns as excavation proceeded. Shear friction angles across joints and beds were estimated from rock wedge fallouts. Friction angles as low as 27º were identified on highly weathered joints. Weathering strongly influenced stability conditions. Examples of bolting patterns to stabilize critical slopes are presented.

Jan 1, 1982

By Richard E. McElvain

The mining and other industries have grown and changed with- respect to their requirements for slurry pumps capable of handling high percentages of abrasive materials. Greater solids concentration, higher heads and pressures, and increased flow arc not possible. Today's equipment delivers up to three times the flow-tonnage and 1.3 times the head per stage as compared with pumps of ten years ago. This results in four times the requirement in size and energy. The new centrifugal pumps are capable of handling these requirements at pressures up to 4826 kPa (700 psi), with 6895 kPa (1000 psi) or more being considered for future systems. The latest pumps, functioning at four times the operating requirement on flow-head, weight eight times more than the previous equipment. Efficiency is increased slightly, to about 75 % to 85%. A testing program on equivalent units has confirmed that the added strength and specific design of heavy-duty pumps can meet demanding engineering objectives. Operating life on difficult-to-pump materials is increased from 500 to over 5000 hours of continuous operation; the ten-fold increase in pump operating time is a major design objective.

Jan 12, 1976