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By E. V. Murphree

CREATION of atomic energy, aside from its influence on war or peace, has posed these basic questions for the world: How soon can energy from atoms be harnessed to do man's daily work? How much of this power will there be, to what degree will it supplant present fuels, and what does it imply for the future of civilization? Answers to these questions may be found in part in analysis of just what atomic energy is and how far its development has come. The answers are encouraging. One of the first questions encountered in considering the application of atomic reactions is whether such reactions can be controlled. Fortunately, this has been adequately demonstrated by the operation of the Government plutonium plants at Hanford, Wash. Here nuclear reactions are carried out on a large scale involving liberation of about a billion B.t.u. per hour. This hourly heat liberation is equivalent to that obtained from about 7100 gallons of fuel oil. It has been possible to operate these plants day in and day out with the reaction controlled at the intensity desired. There should therefore be no question that, under proper conditions, reactions involving nuclear fission can be controlled.

Jan 1, 1946

By F. E. Crane, H. A. Kendall, G. H. F. Gardner

Two effects of a difference in density may be observed in miscible displacement. As the difference is increased from zero there is first a change in mode from multiple fingers to a single finger. A further increase results in a more rapid growth of the single finger. Miscible displacement with multiple fingers has been discussed by Blackwell, et al, whereas miscible displacement with a single finger has been discussed by Craig, et al. In the present paper experiments are described which bridge the gap between these extreme cases. INTRODUCTION Craig, et al,1 investigated the effect of gravity on frontal displacements for circumstances in which the gravity forces were significant. Blackwell, et a1,2 dealt with the other extreme in which gravity forces were negligible. The considerable difference between their results is illustrated in Fig. 1 where the breakthrough recoveries are plotted against the mobility ratio. The experiments described in the present paper were conducted to examine how the transition from the one extreme case to the other occurs when the gravity forces are gradually reduced. The transition is well illustrated by the production history after breakthrough. Fig. 2 shows how the number of pore volumes which must be injected at a constant rate to displace 98 per cent of the original fluid depends on the gravity force. For each mobility ratio there is a transition range, and a very significant change in the number of pore volumes occurs when this range is traversed. This range of the gravity force is physically linked with the formation of viscous fingers. A single finger is predominant for larger gravity forces; a multiplicity of fingers is formed for smaller gravity forces. Improved recovery and the occurrence of multiple fingers is concomitant with a large increase in the amount by which the fluids are mixed within the porous medium. The transition range depends on all the dimension-less groups which characterize the problem; but this dependence has not been exhaustively studied as yet and only fragmentary results are discussed in this paper.

By AIME AIME

COUNCIL PRESIDENT OF THE COUNCIL. CHARLES KIRCHHOFF NEW YORK, N. Y. (Term expires February, 1912.) VICE-PRESIDENTS OF THE COUNCIL. BENJAMIN B. LAWRENCE NEW YORK, N. Y. JOSEPH W. RICHARDS SOUTH BETHLEHEM, PA. ALBERT SAUVEUR CAMBRIDGE, MASS. (Term expires February, 1912.) S. B. CHRISTY BERKELEY, CAL. W. A. LATHROP PHILADELPHIA, PA. GARDNER F. WILLIAMS WASHINGTON, D. C. (Term expires February, 1913.)

Oct 1, 1911

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Jan 1, 1928

By Peter Stubbs

Mr. Agelopas is to be congratulated on a fine paper. Although the presentation was simple and concise, you will all appreciate that a great deal of hard work went into the development of this highly successful repair method. Earlier this year Bethlehem invited a group of our people to witness lug repairs at their Sparrow's Point plant. We have since made lug replacements on a trial basis using their method. The repaired moulds are now back in service. We will compare their performance with regular moulds and with moulds repaired by a technique developed by Dofasco weld shop personnel. I would like to explain briefly some of the various types of ingot mould repairs presently undertaken at Dofasco. The first problem will be familiar to most of you. The lower inside edge of a mould wall may be damaged by spalling, a runout or by the washing action of steel deflected from a badly worn stool cavity. We repair this type of damage by welding.

Jan 1, 1972

Jan 1, 1945

Jan 1, 1935

Jan 1, 1935

Jan 1, 1933

By Laurence W. Casteel

Indian Creek Mine, newest of the St. Joseph Lead Co. properties, is located in southeast Missouri on the flanks of a buried porphyry ridge. Here the orebodies are very irregular in size and shape and have a regional pitch of about 15°, which may vary locally from 0 to 90°. To maintain an economical grade of ore, selective mining is imperative. The room and casual pillar method is employed with 20-ft diam pillars 35 ft apart where possible. Stopes vary in height from 10 to 55 ft. All are too small to supply a loading unit continuously.

Dec 1, 1956

By Heinrich Oscar Hofman

IN THE death of Professor Hofman who was born on Aug. 13, 1852 and died on April 28, 1924, the world has lost a great metallurgist and a great author of metallurgical literature. Measured in time his life was not quite seventy-two years, but measured in work accomplished it was much longer than this. It is not surprising that Dr. Hofman became a great scholar for his father, Karl Hofman, was on the faculty of Heidelberg University, and his early days were spent in these surroundings. He studied in the University under such men as Kirchoff and Bunsen and often spoke of the intimate relations he had with them. Following his course at Heidelberg, he studied at the Clausthal Mining Academy where he graduated with honors, receiving the degrees of Mining Engineer and Metallurgical Engineer in 1877.

Jan 1, 1924

By Dubois Eastman

BEHIND the contrasting liquid-fuel technologies of Germany and the United States lie the basic differences of scarcity and abundance. The chemists and engineers of each nation have developed processes that accommodate available raw materials. In the United States, processing is based on an abundant supply of petroleum, which is refined into a variety of fuels and lubricants. Germany has little indigenous petroleum but has a readily available supply of coal that can be converted into liquid fuels and lubricants. As a result, in Germany several basic processes have been developed for the conversion of coal into synthesis gas (carbon monoxide and hydrogen). In turn, this gas is processed into products. As a normal function of its researches into petroleum processing, the petroleum industry in the United States has made careful studies of various conversion and synthesis techniques. A number of oil companies are carrying out independent development programs with the aim of synthesizing hydro- carbon products that can be marketed at a price that will compete with the price of refined petroleum products. American oil companies hope to perfect synthesis processes that will directly benefit the consumer. A good example of progress in these terms is the synthesis plant at Brownsville, Texas, which is based on the conversion of natural gas to synthetic fuels and other valuable products. When this plant is operated at near capacity, it is expected that the products will be able to compete favorably for the consumer dollar. The complete gasification of coal is a technique well rooted in history. As a controlled process on a small scale, it goes back centuries. As a practical technique on a commercial scale, it dates back to 1839, when "producer gas" appeared in Germany for limited industrial use. By 1873, "water gas," or "city gas" as it is sometimes called, was being manufactured commercially in the United States for use in heaters and stoves. The water-gas process was the cornerstone for modern synthesis. To older methods that were concerned only with carbon and oxygen reactions, it added hydrogen by means of steam. Thus far the goal of conversion was to produce gas for heating, lighting, industrial use, and cooking. The long step forward to synthesis was made in 1927, when Germany started to make gasoline from coal by means of the revolutionary Bergius hydrogenation process. A year earIier, Franz Fischer and Hans Tropsch had announced their process, which finally reached the

Jan 1, 1953

Restrictions on the use of zinc will be a thing off the past in a few months. Government allocations on the metal are also expected to go by the board. Concurrently, action is also expected in reference to lead allocations. Government stockpile goals for zinc have been reached. The International Union of Mine, Mill and Smelter Workers lent support to United Steel Worker demands and at the same time put in their own bid for a 25-cent an hour increase at a meeting held in Denver. While backing the USW, the IUMMSW charged the Steel Workers with membership raiding. Iron and steel companies producing about 92 pct of steel ingots in the United States, showed nearly a 13 pct decline in net profit during 1951, compared with the previous year, despite a 22 pct increase in their combined revenue. Federal income tax rose 61 pct, to more than 012 million. New iron ore reserves are being sought in Canada by Jones & Laughlin Steel Core, The company has acquired exploration options near Petersborough on the north shore of Lake Ontario in Durham, Northumberland and Frontenac Counties. *'A fourth property is southwest of Ottawa, in the Kingston, Ontario area..

Jan 1, 1952

By J. Bruce Clemmer, P. E. Churchward, Carl Rompacek

The paper describes a cyclic method for processing manganese ores using sodium sulphate as the basic reagent. Sodium sulphate is electrolyzed in a diaphragm cell to give an anolyte sodium sulphate acid and a catholyte containing caustic soda, a part of which is carbonated in a cyclic manner to form soda and reduced ore is leached with the anolyte to dissolve the manganese and the impurities are precipitated by addition of catholyte. Manganese in the pregnant solution is precipitated as synthetic rhodochrosite with a carbonated catholyte, and sodium sulphate is regenerated. Calcining the manganese carbonate site a high-grade product and the carbon dioxide is returned to the carbonation step. the results of laboratory tests using cells equipped with synthetic fiber diaphragms and permselective membranes which permit transfer of using or cations during electrolysis are described. The article from which the above abstract is reprinted appears in Trans. AIME (1955) 203, p. 51; Journal op Metals (January 1955).

Jan 1, 1956

Jan 1, 1913

By J. M. Silliman

ISOMETRICAL drawing and clinographic projection are generally preferred to perspective drawings for representation of small objects or complicated mechanisms, as they present to the eye a sufficiently accurate picture of the object, while they possess great advantages over perspective in the simplicity and rapidity of execution, and the facility they give for taking measurements directly from the drawings.

Jan 1, 1882

By J. M. Silliman

Isometrical drawing and clinographic projection are generally preferred to perspective drawings for representation of small objects or complicated mechanisms, as they present to the eye a sufficiently accurate picture of the object, while they possess great advantages over perspective in the simplicity and rapidity of execution, and the facility they give for taking measurements directly from the drawings.

Jan 1, 1882

Jan 1, 1931

By A. L. Engel

STRICTLY speaking, ore-dressing does not commence until after the ore is in the mill bins, but where complex ores are treated and their minerals separated to make the best commercial concentrate with the lowest economical tailing, ore-dressing problems begin and often center in the mine itself. This does not refer to the grade of the ore, but rather to the frequent condition in which metallurgical results radically different from customary are obtained because of changes in the character of the ore treated. Different varieties of ore can usually be identified as coming from well-defined depths or zones in the mine, or from known sections of the orebody. Varying degrees of alteration of the ore, inclusions of harmful gangue material, or variations in the quantities of component metallic minerals are often causes of temporarily bad metallurgical results in otherwise successfully operated plants, especially those employing differential flotation to. recover several valuable minerals contained in the ore.

Jan 1, 1931

Jan 1, 1931