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By J. B. Nau

A short time ago some interesting experiments concerning a new steel-making process in the open-hearth furnace were made by the writer at the Croton magnetic mine, N. Y.

Jan 1, 1892

Jan 1, 1891

NAME "Utah" is derived from the name of the Indian tribe, variously spelled "Yuta," "Ute," "Youta." "Uta." "Eutaw," and finally "Utah." It means "in the tops of the mountains," or "on the heights." The state emblem is the "Beehive," typical of industry. State nickname is "Beehive State." AREA Utah is the tenth state in area. It contains 84.990 square miles, of which 2.806 miles are water. When admitted as a territory in 1850. Utah included all the area from the east line of California to the summit of the Rocky Mountains between the 37th and 42nd parallels, which embraced practically all of the present state of Nevada, all of western Colorado, part of Idaho and part of Wyoming, in addition to the present area of Utah.

Jan 1, 1925

Jan 1, 1916

By Quentin D. Singewald, B. S. Butler

Some of the broader relations between structure and ore deposition along the London fault, deduced from a thorough study of the geology of the eastern part of the Mosquito Range, should be of general interest to economic geologists. The first part of this paper is a generalized statement of the geology of the region in which the London fault is located; it may be supplemented by reference to several earlier publications by the writers and to the U. S. Geological Survey's Professional Paper 148, on the Leadville district. The second part deals with the structure of both the fault and the disturbed zone adjoining the fault. The third part discusses the salient features of the ore deposits, particularly emphasizing structural control. The two generalized maps are complementary to one another but contain too many data to show on a single small map. The London fault is between Leadville and Alma, and the ore deposits along it are said to lie in the Alma district. Field work in this district, during six summers since 1927, has been a part of the cooperative work of the U. S. Geological Survey, the State of Colorado, and the Colorado Metal Mining Board. The writers have made use of work by R. D. Butler, J. W. Vanderwilt and R. E. Landon. G. F. Loughlin and C. H. Behre, Jr., who have worked on the west side of the range, have contributed valuable suggestions. Mining men of the district have aided in many ways. General Geology Pre-Cambrian Rocks.—The oldest rocks in the district are schists, correlated with the Idaho Springs formation of the Front Range. Quartz-mica schist predominates, but other types occur locally; almost everywhere the rocks show considerable lit-par-lit injection. Intrusive into the schists are two varieties of granite, only one of which is widespread. It is a fine-grained, porphyritie, gray granite correlated with the Silver Plume granite of the Front Range. Near the head of Buckskin Gulch a

Jan 1, 1937

For the seventh consecutive year, the value of nonfuel mineral raw ma¬terials produced in the US set a new record, reaching almost $20 billion-up 12.7% from the previous year, according to the US Bureau of Mines. The Bureau reported that this mineral production was the basis for about $200 billion worth of processed materials of mineral origin.

Jan 5, 1979

By H. I. Smith

THE technical and safety press have devoted much space in support of or in opposition to the use of booster and auxiliary fans in coal mines. The Mine Safety Board of the U. S. Bureau of Mines has given the matter consideration, and the Mine Ventilation Committee of the A. I. M. E. is now seeking a discussion of the merits and demerits of such fans to guide it in formulating recommendations. In this paper, I will set up some principles on which I believe most engineers will agree and from which we may work toward a decision, though as to what that decision shall be there may be a difference in opinion. Before stating the points on which I believe. there is accord, I will distinguish between booster and auxiliary fans.

Jan 1, 1927

By R. F. Mehl

Jan 1, 1961

Jan 1, 1932

By H. J. French

WITHIN the past few years, particularly because of the rapid growth of the airplane industry during the war, considerable attention has been paid to the manufacture of light-wall cold-drawn seamless and welded steel tubing for structural purposes. While the manufacture of such tubing is not, in itself, a difficult matter, some difficulties have. been encountered in producing the same under specifications requiring definite physical properties. It is the purpose of this paper to describe the methods of manufacture and the properties that may be obtained by such methods for tubing coming within about ½ to 2 in. (12.7 to 50.8 mm.) outside diameter and 10 to 22 Birmingham wire gage (0.134 to 0.028 in. wall thickness). Such tubing is largely used as structural material in the aircraft industry, and it is of the utmost importance that the physical and chemical properties should be known, and also that the various factors entering into the manufacture should be under such control as to allow these properties to be varied and held within definite limits. In general, tubing may be divided into four classes: namely, specialty tubing, such as riveted-sheet or plate, lock jointed, etc.; brazed tubing; welded tubing; and seamless tubing. Welded tubing may be divided into hot product, such as lap welded and butt, welded, and cold product, such as acetylene and electric welded. Seamless tubing may be hot rolled or cold drawn.

Jan 9, 1919

By H. W. Gillett

BATTELLE Memorial Institute is an endowed in stitution for scientific research in metallurgy, fuels, and allied fields, established by the will of Gordon Battelle, 2nd, as a memorial to his father, Colonel John Gordon Battelle. Before I tell you more of what Battelle Memorial Institute is, I want to go back a bit and tell you why it is. Colonel Battelle began his services in the iron and steel industry in Wheeling in 1866 and in 1883 came to Ohio, where he successively engaged in the iron and steel industry in Cincinnati, Piqua and Columbus. The family had been prominent in Ohio affairs since 1788, when Gordon Battelle's great-great-grandfather came from New England to settle in Marietta. He was one of the pioneers and a member of the famous "Ohio Company."

Jan 1, 1929

Jan 11, 1951

A-Metal Mining B-Minerals Beneficiation F-Coal H-Industrial Minerals

Jan 11, 1950

In late May, at its final session in Nairobi, Kenya, the UN Conference on Trade and Development (UNCTAD) narrowly rejected the US proposal for a new International Resources Bank suggested by Secretary of State Henry Kissinger. The proposal was defeated by a roll-call vote of 33 to 31, with most of the nay votes cast by communist countries, and with 89 of the less-developed countries abstaining or absent.

Jan 7, 1976

By Edwin S. Sperry

Metals differ widely in their behavior under the cuttingtool. Some, like iron or steel, require a slow speed and light feed, a tool shaped differently from that used for other metals,

Jan 1, 1898

By A. W. Fahrenwald

THE function of the classifier in modern fine-grinding practice is to remove a finished product from the grinding-mill discharge, leaving material that needs further comminution. The classifier, therefore, makes two products: (1) "finished" product, which overflows the rim of the classifier tank, sometimes referred to as "slimes" or as "classifier overflow," and (2) "unfinished" product, which settles to the sloping bottom of the classifier tank and is removed by dragging or raking. This product is generally referred tows "sands" or "oversize." One of the outstanding features of the closed-circuit classifier is its ability automatically to return the unfinished product of the ball-mill discharge to the feed end or scoop box of the ball mill. This is a distinct advantage because it avoids dilution of the ball-mill feed, and, furthermore, the particular method of removing the settled sand, by raking it up the inclined bottom of the classifier, gives a classifier discharge containing a minimum of water. This leads to maximum classifier efficiency, in this type of classifier, because the maximum volume of water is displaced upward by the settling sands. The closed-circuit classifier is required to deliver a finished pulp of closely specified density requirements, therefore added hydraulic water generally is not permitted.

Jan 1, 1930

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 A. F. Buddington

INTRODUCTION EVER since a genetic connection between many ore deposits and magmas began to be widely recognized, some two-score years ago, there has been much discussion of the complex and intricate problem of the genetic association of specific kinds of mineralization with specific kinds of igneous rocks. General discussions of the latter problem and pertinent data have been given by S. F. Emmons, Kemp, Lindgren, Niggli, Rastall, Spurr, Vogt, and others. In this paper no attempt is made to deal with mineral deposits genetically associated with volcanic rocks, but only with those presumed to be related to exposed intrusive masses. The writer is indebted to E. S. Bastin, F. F. Grout, Edward Sampson, and to the members of the committee in charge of the preparation of the volume, for a critical reading of the manuscript and many worth-while suggestions.

Jan 1, 1933

By Thys B. Johnson

Traditional mine planning concepts are discussed and suggestions for improvement through use of the developed model are proposed. The approach developed in this paper allows optimal planning of the complete mining-concentrating-refining system over the entire planning horizon and permits the system to dictate how and when to process a block of material, i. e., a dynamic cutoff.

Jan 1, 1969

By Oscar Harder

IT is now just a quarter of a century since Fred W. Taylor§(23) pub-lished his classical paper On the Art of Cutting Metals, describing -his researches in which he, in cooperation with Maunsel White, had developed what is essentially the modern method of heat-treating high-speed steels. Regarding this research, Dr. Sauveur, (22) in his address on Steel Wizards, Past and Present, at the annual banquet of the American Society for Steel Treating in Philadelphia in 1920 said, "The discovery of high-speed steel, or if you prefer, of the treatment imparting high-speed properties to certain steels by Taylor and Maunsel White I am inclined to consider as our one epoch-making contribution to the metallurgy of steel." It was at about that same time (1900) that Taylor exhibited high-speed steels, heat-treated by the improved process, at the World's Exposition in Paris and attracted much attention by showing that the steels would operate at such feeds and speeds that the tips of the tools were visibly red hot. This observation must have started metallurgists to wondering regarding the relative hardness of the various steels at red-heat temperatures. Considerable work has indeed been done in an effort to measure the hardness of high-speed steels and. related materials in the red-heat range, using various methods. . The results, however, have been only partly satisfactory, owing to experimental difficulties. The present investigation had as its immediate inception an address by J. V. Emmons, of the Cleveland Twist Drill Co., to the Columbus Chapter of the American Society for Steel Treating in 1931, in which he deplored the fact that comparatively little was known with regard to the hardness of high-speed steels at elevated temperatures, in spite

Jan 1, 1933