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By Eugene H. Dawson

MICA is a mineral that once was a familiar sight as fireproof windows in stove and furnace doors and as lamp chimneys and shades. Since 1878, the beginning of the electrical age, the use of mica for such purposes has gradually declined and its use in electrical equipment and appliances has developed to such an extent that the known sources of supply are scarcely equal to the demand. With the increasing capacity of electric generating units, the size of mica sheets found in nature was inadequate. However, in 1894, a process was developed whereby thin films or splittings cemented with shellac or other binders could be pressed into large sheets. 18 The introduction of radio in the early 1920s created such a heavy demand for the smaller sizes of mica that on March 22, 1938, mica was included among 23 commodities on the list of strategic materials approved by the United States Army and Navy Munitions Board. To be included in this list, the material must be one whereof the domestic supply is not sufficient to meet the demand. COMPOSITION Mica is a complex mineral composed principally of the silicates of potassium, aluminum, and magnesium. Less prevalent species contain, as essential components, lithium, vanadium, and chromium. Iron usually is present either as an essential component or as an impurity. The mica group comprises some nine different species, five of which, muscovite, phlogopite, vermiculite, lepidolite, and biotite, are widely used in industry. Lepidolite and zinnwaldite (lithium micas) and roscoelite (vanadium mica) are sources of lithium and vanadium. Muscovite, "white mica," is potassium mica. Theoretical formulas H2KAl3(SiO4)3. There are two varieties, distinguished as to color, known in industry as ruby and green. In crystals or "books," the colors each range through varying shades of red and green. However, when split into thin films, all micas, except biotite and phlogopite, are colorless and transparent. Muscovite frequently is stained red or black by thin films of iron oxide between the laminae. The staining usually is derived from magnetite, which sometimes is found as unaltered crystals.

Jan 1, 1949

R. H. SWEETSER, Columbus, Ohio.-My experience with oxygen in the blast is limited to the use of one tank of oxygen in melting out a chilled anthracite furnace. The oxygen was introduced through the peephole of the tuyeres and opened them in a very short time. We could see that an intense heat was generated just as soon as the oxygen struck the fuel. I agree with the committee in respect to many. of the things that will probably happen in the iron blast furnace, particularly as to the speeding up of the operation. There will undoubtedly be changes in the shape of the blast furnace, and if I were designing one today I should hesitate about the form to give it. Mr. Kirby suggested that the proper shape might be rectangular. Some of the men of the American Rolling Mill Co. have reached the same conclusion, as a result of Royster and Joseph finding that the combustion zone in the front of the tuyeres extended into the furnace less than 40 in. If this is correct, we might build the furnace with an elongated rectangu-ular hearth having the shorter dimension a little over 80 in. and secure. a very intense temperature in the hearth. The committee's report said, "With more oxygen available in the blast, the smelting ability of the furnace will be increased beyond the' speed of the preparing zone in the shaft." This can be controlled by providing ample facilities for getting stock into the furnace, and this will be one of the biggest changes in blast-furnace construction. The question has been raised as to finding suitable refractories to withstand the increase of hearth temperature. If the furnace can be kept full, the descending column of cold material will probably take care of the increased heat from more rapid combustion of the coke. At the Cleveland meeting, in 1912, the iron blast-furnace men listened with great interest to a paper on copper slags; from Mr. Kirby's paper, it looks as though they might again have to go to the copper men, for many of the problems of the iron blast furnace of the. future that uses oxygen may be worked out on lines of the copper blast furnace.

Jan 11, 1924

By A. B. Young

THE difficulties encountered in the preparation of. the lead smelter charge for the blast furnace and in the roasting and sintering of the ores, and the expert means taken for the preparation of these materials since the introduction of flotation concentrates into the lead smelter charge, have been described by W. H. Eardley1 and R. A. Wagstaff.2 FUNCTION OF ROASTERS AND BLAST FURNACES The lead smelter has first its roasters and its sintering devices, of which the primary object is the removal of sulfur from the ore or from the charge. The blast furnace follows; its function being the elimination of the gangue material left in the charge-the elimination of the insoluble, the iron, the zinc and the lime from the metallic lead. The secondary object is the separation of copper from the lead. A lead blast furnace is a sensitive apparatus. The materials composing the charge must be marshalled inn certain proportions before they will, make a fluid slag which will separate from the metallic lead. The silica, iron, lime and zinc must be put together in proportions that usually do not exist naturally in the ores, therefore fluxes are necessary. FUNCTION OF THE FLOTATION CELL The flotation cell-speaking from the standpoint of a lead concentrate-has taken over part of the work hitherto performed entirely by either gravity concentration or the lead blast furnace. It has eliminated gangue from the concentrate and separated waste products from the lead. In so far as it has done that, it has usurped some of the function of the lead blast furnace; and it is much cheaper to run a flotation cell than a lead blast furnace. The effect in Utah, and it will be similar to effects in other districts, has been to remove a great deal of the gangue by means of flotation, whereas in the old days it was eliminated by means of smelting. In this district, as in others, the insoluble content of the ores has been greatly out of proportion to the iron and lime content to make a proper slag

Jan 1, 1928

By R. W. Raymond

The sudden death of Captain Jones, September 28,1889, became known to his fellow-members on the eve of the Ottawa meeting of the Institute; and at that meeting, Mr. Charles Albert Ashburner, of Pittsburgh, expressed with unaffected feeling and unpremeditated eloquence the sorrow of all. Mr. Ashburner subsequently undertook to revise and extend, for in in the Transactions, the remarks he had made at Ottawa; but death surprised him also, in the midst of his labors; and it has become my duty and privilege to prepare from the memoranda he left behind, the present brief and inadequate notice. To me, who knew and loved them both, this task of double sorrow recalls them both, with a peculiar sense of presence and of absence. They seem to speak from another land, not far away, yet not with human voices—like an echo and its echo. William Richard Jones was born in Luzerne county, Pennsylvania, February 23, 1839. His father was Rev. John G. Jones, a Welsh minister, who had immigrated to the United States in 1832. William was the eldest son, and his father's failing health made it necessary for him to begin early the work of self-support. At the age of ten, he was apprenticed to the Crane Iron company, of Catasauqua, and in this humble capacity entered upon the profession in which he was to become famous. Unquestionably, the thorough acquaintance with all details, acquired by working his way from the bottom to the top, was one secret of the conspicuous executive ability which characterized him in the height of his career. According to a letter from Mr. J. H. Geer, Assistant Chief Engineer of the Cambria Iron Company, Mr. Jones entered the service of that company in 1858 or 1859 as a machinist, and continued to work in that capacity until July, 1862, when he enlisted as a private in the 133d Regiment of Pennsylvania Volunteers, in which he afterwards commanded a company. The regiment was mustered out of service in 1863, and Captain Jones re-enlisted in the 194th

Jan 1, 1890

By H. G. Doll

A new electrical logging method is described which measures the resistivity of small volumes of material near and behind the wall of the bore holes. The very small electrode systems used are supported in the face of the flexible insulator pad of appropriate dimension maintained in contact with the wall. The measurements are recorded simultaneously with two different electrode spacings. This method provides a very detailed record of the formations and particularly of the permeable beds traversed by the bore holes. The application of MicroLog to the location of permeable zones within compact formaltions, such as limestone, and to the determination of the amount of sand existing in sequences of thin shale and sand streaks is discussed. The possibility of quantitative determination, providing a step toward the evaluation of formation porosity and mud cake thickness, is also examined. Field examples illustrate the essential features of the method. INTRODUCTION In conventional electrical logging, the spontaneous potential (SP) log is used to delineate the permeable beds, and the resistivity logs are used primarily to provide indications concerning the fluid content of the beds. When the formations are much more resistive than the mud, as happens, for example, in limestone fields, the SP currents are short-circuited by the more conductive mud column, with the result that the SP log is quite rounded. In that case, the SP log generally gives the approximate location of the permeable formations but it cannot be used for an accurate determination of the boundaries of each permeable bed.' Solutions for the problem of obtaining a better determination of the permeable beds in limestone fields were developed from two angles. One approach consisted in improvements to the logging of the SP, as given by Selective SP logging and Static SP logging. These new methods, which have been described in an earlier paper,' give good results when the mud is not too salty, but they are still in a somewhat experimental stage, mostly because the development efforts have lately been concentrated on another approach to the problem, i.e., the MicroLog.

Jan 1, 1950

By Robert S. Dalzell, Ernest A. Curth

Following the introduction of shields to the U.S. longwall mining scene and the steady increase in the number of shield faces during recent years, the occurrence of longwall -ground-control -associated accidents has shown a welcome downward trend. But even though the accident experience is favorable, problems exist. New mining systems, however efficient, have run afoul of roof control. Shield faces have suffered extended stoppages because of roof cavities. Therefore, the Bureau of Mines has reviewed foreign remedial techniques to evaluate their potential for domestic application. Such technology includes cribbing, strain absorbent modules (SAM'S), inflatables, wire meshing, chemical rock stabilization, synthetic foams, and monolithic fills.

Jan 1, 1984

By W. M. Myers

THE hydraulic properties exhibited by the calcination products of certain limestones were recognized at an early datemore than 2000 years ago. It was known that calcined limestone with the addition of other minerals would react with water and produce an insoluble and stable product. This material could be cast in desired forms or could be used as a cement for the unification of other materials in large masses or for bonding brick or masonry structures. Cements are essentially mineral glues and it is their ability to unify other materials plus their fluidity when first mixed with water, enabling the mass to assume any desired shape, that has made them so extraordinarily useful to modern industry. Like other glues, cements do not exhibit their maximum strength when used alone and only when mixed with proper aggregates do their optimum properties appear. The resulting concrete, a mixture of cement, mineral aggregates and frequently of reinforcing steel, exhibits the most desirable properties of the individual constituents with regard to tensile strength, stability and permanence. The speed with which such mixtures can be -prepared and installed in place with mechanical equipment has facilitated their adoption by the engineering profession concerned with the construction industries. The development and application of improved methods of manufacture have resulted in such economies that the finished product can be sold at a remarkably low price. In addition, the necessary raw materials are of such common occurrence and wide geographic distribution that the manufacture of cement was established in 34 of the 48 states by 1946. Plants under construction will add to this number. In recent years the industry has been characterized by the development of a number of new cements designed to possess special properties essential for use in unusual environments. These have introduced the use of some new raw materials and also have complicated the processes of manufacture. In the following pages, the major varieties of cement of commercial importance are treated in the chronological order of their appearance on the market.

Jan 1, 1949

By Percy Hopkins

KIRKLAND LAKE, the second most important gold area in Ontario, is situated in the north¬eastern part of the Province, 392 miles north of Toronto by railway. It is reached by a five-mile macadam road from Swastika, a village on the Temiska-ming & Northern Ontario Railway, 63 miles north of Cobalt. Gold, was first found at Kirkland Lake in 1911 by W. H. Wright. on claim No. 1830, now a part of the Wright-Hargreaves mine. In January, 1912, the metal associated with various tellurides was found by Harry Oakes and George Tough on the Tough-Oakes property 3/4 mile east of the lake. The shipping of hand-sorted, extremely high-grade ore, valued at $350 to $450 in gold per ton, from this property created great interest and resulted in numerous other discoveries. The early developments of the area, however, were much retarded on account of war conditions, labor troubles, and owing to the ore zone being largely under the bed of Kirkland Lake or in drift-covered depressions. It was not until early in 1918, when the Lake Shore Co. found its rich orebody under the bottom of Kirkland Lake, that the various ore deposits were believed to be more or less continuous along one main vein system. From that time most of the work in the area has been done along the "main vein" with gratifying results. Production began late in 1912, and up to the end of March, 1923, the five producing mines have yielded gold, with some silver, valued at $8,379,403. The production in 1922 was $2,162,548; that of 1923 should be over $3,000,000. The same general assemblage of rocks which occurs at. Kirkland Lake extends easterly for many miles to Larder Lake and beyond; hence there is a large area containing formations favorable for gold prospecting. In this general area numerous prospects are being operated, and among the most promising ones, may be mentioned the Argonaut, Crown Reserve and Asso-ciated Goldfields near Larder Lake. A 25-mile branch railway is now being constructed across the mineral area from Swastika to Larder Lake, passing through Kirkland Lake.

Jan 8, 1923

By Howard A. Meyerhoff, J. Earl Frazier

It is not known when silica sand was first noticed along the north coast of Puerto Rico, but the first mention of its occurrence was made in 1922, by N. L. Britton,1 who described its presence in isolated patches extending from Loiza westward beyond Manati. Further observations were made in 1925 and 1926 by Meyerhoff,2 who extended the known occurrences still farther westward to the low hill belt in the Quebradillas limestone immediately south of Hatillo. The extraordinary purity of the sands, which in most localities exhibit no contamination from the non-siliceous materials surrounding them, was quickly appreciated, and the feasibility of utilizing them for the manufacture of glass was investigated, initially by the Committee on Mineral Resources3 and later (1936) by the Puerto Rico Recon-structionAdministration and by H. C. Ray, mining engineer of the Insular Bureau of Mines. In 1934 samples submitted to the Hazel Atlas Glass Co., of Washington, Pennsylvania, were reported to have the composition as shown in the table on column two. Appreciation of the quality of the sand prompted geological and quantitative studies of the deposits, as well as cornmercial investigations to determine the feasibility of utilizing it locally or on the mainland for the manufacture of glass containers. Distribution of the Sands The quartz sands consistently lie within the outcrop area of the Quebradillas limestone, the youngest of the Miocene formations in the Tertiary coastal plain that fringes the northern coast of the Island. Many of the deposits are closely associated with limestone outcrops, but some appear to be embedded in lagoonal sediments at some distance from rock exposures, and at least one deposit, near Dorado, has been reworked by waves and littoral currents. With this single known exception, the deposits consist of irregular, patternless patches of white sand, which have sharply defined contacts with the surrounding material. Although patches of sand are present in a 90-km. belt that is not more than 5 km. wide, extending from Loiza to Hatillo, they attain maximum size, purity and number in the north central coastal area between Dorado and Barceloneta. Fifty separate deposits have been mapped in Lago Tortuguero and to the south of it, some as small as 50 ft. in diameter but

Jan 1, 1948

By J. Earl Frazier, Howard A. Meyerhoff

It is not known when silica sand was first noticed along the north coast of Puerto Rico, but the first mention of its occurrence was made in 1922, by N. L. Britton,1 who described its presence in isolated patches extending from Loiza westward beyond Manati. Further observations were made in 1925 and 1926 by Meyerhoff,2 who extended the known occurrences still farther westward to the low hill belt in the Quebradillas limestone immediately south of Hatillo. The extraordinary purity of the sands, which in most localities exhibit no contamination from the non-siliceous materials surrounding them, was quickly appreciated, and the feasibility of utilizing them for the manufacture of glass was investigated, initially by the Committee on Mineral Resources3 and later (1936) by the Puerto Rico Recon-structionAdministration and by H. C. Ray, mining engineer of the Insular Bureau of Mines. In 1934 samples submitted to the Hazel Atlas Glass Co., of Washington, Pennsylvania, were reported to have the composition as shown in the table on column two. Appreciation of the quality of the sand prompted geological and quantitative studies of the deposits, as well as cornmercial investigations to determine the feasibility of utilizing it locally or on the mainland for the manufacture of glass containers. Distribution of the Sands The quartz sands consistently lie within the outcrop area of the Quebradillas limestone, the youngest of the Miocene formations in the Tertiary coastal plain that fringes the northern coast of the Island. Many of the deposits are closely associated with limestone outcrops, but some appear to be embedded in lagoonal sediments at some distance from rock exposures, and at least one deposit, near Dorado, has been reworked by waves and littoral currents. With this single known exception, the deposits consist of irregular, patternless patches of white sand, which have sharply defined contacts with the surrounding material. Although patches of sand are present in a 90-km. belt that is not more than 5 km. wide, extending from Loiza to Hatillo, they attain maximum size, purity and number in the north central coastal area between Dorado and Barceloneta. Fifty separate deposits have been mapped in Lago Tortuguero and to the south of it, some as small as 50 ft. in diameter but

Jan 1, 1948

By J. L. Sepulveda, R. F. Yap, R. Jauregui

INTRODUCTION The Third Theory of Comminution, oftentimes called the Bond Theory, was first published by Fred C. Bond in 1952. Since then, it has been widely used in the milling industry to size crushing and grinding equipment as well as to predict and evaluate their performance. Although two other comminution theories were advanced almost a century earlier, one by Rittinger, 1867, and the other by Kick, 1885, their use was limited because they did not agree with actual commercial comminution systems (Bond, 1961). According to Bond's Third Theory, the work input is proportional to the new crack tip length produced in particle breakage, and equals the work represented by the product minus that represented by the feed. For particles of similar shape, the crack tip length is equivalent to the square root of one-half the surface area, and the new crack length is proportional to [(1/vT - vF)]; where P and F are particles diameter of product and feed, respectively. For practical calculations, the particle diameter can be expressed in terms of the 80% passing sizes, P and F, respectively. Therefore, the work input is given by, [10 _ 10', W = Wi [7P_7F(1)] Where W = the energy input to the mill, (kwh/t) Wi = Work Index, (kwh/t) P = square sieve opening which 80% of the product passes, (microns) F = square sieve opening which 80% of the feed passes, (microns) Equation (1) is the mathematical statement of the Third Theory, or the Bond equation. Numerically, the work index is the energy required in kwh/t to reduce a given material from theoretically infinite feed size to 80% passing 100 microns. The work index of a particular material is determined in the laboratory by conducting the standard Bond grindability test. Bond developed separate tests for the rod mill and the ball mill. The simplified test method described in this paper, which is used at Anaconda Research Center to approximate the work index, is an alternative procedure to the ball mill

Jan 1, 1982

OUR 78th Annual Meeting was, technically and attendance-wise, one of the greatest to date. No one who came to New York's Hotel Statler had time to hear all 266 papers, or to attend all 70 sessions and 27 committee meetings, or to shake the hands of the more than 3000 engineers, educators, students and executives who attended-but no one was lost in the crowd. For crowds always dwindle down to groups of two and three and four, and those are the little sessions which make our meetings well worth attending. Herewith four pages of photographic highlights and sidelights on the February gathering.

Jan 3, 1950

By T. Egleston

The direct process for the manufacture of iron which is principally used in the United States, in New York and New Jersey, is called the Jersey forge, the Champlain forge, the Catalan forge, the Bloomary forge or fire, and sometimes a Forge fire. Dr. T. Sterry Hunt, who has discussed the process as applied to the beach sands of Canada as well as to ores, in the Report of the Canadian Geological Survey for 1867-69, has shown that the name of Catalan forge is incorrect, as this process in no way resembles the Catalan, but is really the old German b1oomary modified by long use in this country. Dr. Hunt gives the probable history of the introduction of the process into the United States, and a series of historic citations of great interest relating to it. Notwithstanding the improvements which have been made in the constrnction of the furnace and its greater output, the process to-day, in all its essential features, is carried out as Karsten described it. It should now be known as the American Bloomary. The name of Jersey or Champlain forge or fire is not sufficiently distinctive. The name of Bloomary, by which the process is usually distinguished, is objectionable, not because it is incorrect but because it is indefinite, as the Knobbling fires, which are a very slight modification of the Walloon process, for making blooms either from pig iron or by sinking scrap, are also called Bloomaries, and although Knobbling fires are only used in a few localities where charcoal pig is made, and special grades of charcoal-refined blooms are required, one does not, without an explanation, know whether the blooms are being manufactured from ore or pig. The name Forge fire is equally indefinite, as it might just as well apply to any of the five direct methods of making blooms which have been in use in Europe, but which have now mostly gone out of date. The name of American Bloomary, however, is the one which most completely describes it, and is the one least open to objection. The names of' German, Jersey, and Champlain bloomary are too local, and these adjectives are thought unnecessary by those who use the process, and we shall not therefore describe it under any of these names, but as the American Bloomary process.

Jan 1, 1880

By Raymond C. Moore

The oil-producing districts of Kansas comprise the northern portion of the so-called Mid-Continent field. As shown in the accompanying map, these districts are located chiefly in the southeastern and south central parts of the state. A considerable area in southeastern Kansas, extending northward nearly to Kansas City, has long been known as oil territory, the productive wells being distributed in patches or spots of irregular size and shape, the location of which is controlled by conditions of rock structure, and by the texture and porosity of the "sands" beneath the surface. In south central Kansas, there are a number of producing fields, the location of which appears to be controlled chiefly by well-defined structure. The most important districts are those in Butler County, especially that in the vicinity of El Dorado, which was for a time the most productive district in the entire Mid-Continent field. Recently new production of importance has been brought in the vicinity of Peabody and present development is active to the north across Marion County. Tests in the western parts of Kansas have not been successful in finding new petroleum fields. Histoby The first well drilled for petroleum, in Kansas, was near the town of Paola, Miami Co., about 40 mi. southwest of Kansas City, in the summer of 1860, only a few months after the completion of the famous "Colonel" Drake discovery well in Pennsylvania. Kansas appears to be the second state to engage in a serious attempt to find oil by drilling. The Civil War caused the temporary abandonment of attempts at oil development in the state. It was in the vicinity of Paola, where numerous oil seepages had been observed, that the first well producing oil in commercial quantities was drilled,' where also gas was first piped to the city for commercial use. Prospecting spread southward into Linn County and northward into

Jan 1, 1921

By A. B. Young

The difficulties encountered in the preparation of the lead smelter charge for the blast furnace and in the roasting and sintering of the ores, and the expert means taken for the preparation of these materials since the introduction of flotation concentrates into the lead smelter charge, have been described by W. H. Eardleyl and R. A. Wagstaff.² Function of Roasters and Blast Furnaces The lead smelter has first its roasters and its sintering devices, of which the primary object is the removal of sulfur from the ore or from the charge. The blast furnace follows; its function being the elimination of the gangue material left in the charge—the elimination of the insoluble, the iron, the zinc and the lime from the metallic lead. The secondary object is the separation of copper from the lead. A lead blast furnace is a sensitive apparatus. The materials composing the charge must be marshalled in certain proportions before they will make a fluid slag which will separate from the metallic lead. The silica, iron, lime and zinc must be put together in proportions that usually do not mist naturally in the ores, therefore fluxes are necessary. Function of the Flotation Cell The flotation cell—-speaking from the standpoint of a lead concentrate—has taken over part of the work hitherto performed entirely by either gravity concentration or the lead blast furnace. It has eliminated gangue from the concentrate and separated waste products from the lead. In so far as it has done that, it has usurped some of the function of the lead blast furnace; and it is much cheaper to run a flotation cell than a lead blast furnace. The effect in Utah, and it will be similar to effects in other districts. has been to remove a great deal of the gangue by means of flotation, whereas in the old clays it was eliminated by means of sme1ting. In this district, as in others, the insoluble content of the ores has been greatly out of proportion to the iron and lime content to make a proper slag

Jan 1, 1928

By Paul B. Barton

Unconventional mineral deposits are those that differ significantly from productive deposits in mineralogy, grade, or geologic setting. Thus, the initial representatives of each deposit type are, by definition, “unconventional” until they are exploited. The “unconventional” status changes to "conventional" because of economic shifts (e.g., bulk silver ores), because of technological innovations (e.g., froth flotation), or simply through the recognition of, and production from, novel mineral concentrations. Heretofore the discovery of new deposit types has been almost entirely accidental, but the long- established concept of the geochemical cycle provides a nearly untouched opportunity and challenge for the application of geochemistry in predicting novel, potentially economic, mineral concentrations.

Jan 1, 1983

By R. C. Allen

About four years ago the writer proposed a revision of the correlation of the Huronian formations in Michigan, and noted the bearing of the question on the correlations of the Huronian rocks in Wisconsin and Minnesota.1 Dr. C. K. Leith opposed this revision and argued for the retention of the correlations of the United States Geological Survey, published in 1911,2 for which he and Dr. Van Hise were mainly responsible. As late as June, 1917, Harder and Johnson, following Leith, thought it "premature to change radically a correlation based on years of careful field work."3 The work of Wolff on the Mesabi and Cuyuna Ranges, of Hotchkiss on the Gogebic Range (unpublished), and of the writer and assistants on the Michigan ranges, together with data developed by exploratory and mining operations, has introduced so many new facts not recognized in the scheme of the U. S. Geological Survey that the correlations of 1911 must be considered, in some important respects, obsolete. Indeed, new data are accumulating so rapidly that any classification, which for the moment may seem best to explain the facts, is almost immediately modified or refined by further observations. The problem of Huronian correlations is difficult, but interesting and important. With the aid of fossils, stratigraphers of the post-Algonkian formations have been able to show that slight disconformities mag separate strata of vastly different ages, and that within physically conformable strata may be concealed a hiatus of great magnitude. In the non-fossiliferous Huronian group, minor physical breaks in the strata are only beginning to attract attention, and it is too early to discuss what bearing these will have in correlating the formations of one area with those of another, but it is safe to say that the "lost intervals" which are not disclosed by physical relationships will remain forever lost; therefore we may not hope to discover the ultimate truth concerning the

Jan 1, 1920

By S. Inaba, K. Taguchi, T. Uenaka, I. Mizuguchi, K. Umeji, H. Isako

At Kobe Steel Ltd., various improvements in pellet quality have been carried out since beginning lime-fluxed pellet production. Especially, dolomite-fluxed pellets, developed in 1975, have superior high temperature properties. With this improvement, successful BF performance has been achieved. But, in order to achieve more successful BF performance, improvements of physical properties such as the shape factor, reposed angle, and the bulk density are desired. Now, crushed pellets have been developed for the improvement of those characters. The test operation with these new pellets in Kakogawa No. 2 BF was carried out with successful results. This report describes the development of crushed pellets and their use in BF.

Jan 1, 1986

By Toyohiko Hirota, Fukuo Itoh

Oil and natural gas aside, sea floor mineral resources currently being exploited in Japan are offshore sand and gravel and deep-sea manganese nodules. The mining of sand and gravel has already started. With regard to manganese nodules, the geophysical investigation and the study of the mining method are also underway. This report outlines the activity of a few Japanese firms, the Deep Ocean Minerals Association formed by some 30 private firms, Government agencies, a public corporation and two government research institutes. Researches on new exploration instruments, properties of deep-sea sediments and the mining method currently conducted by the National Research Institute for Pollution and Resources are described in detail.

Jan 1, 1976

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who registered at Institute headquarters during the period Apr. 10 to May 10, 1915: William W. Elmer, Tuttletown, Cal. R. R. Freeman, Jr., Wollaston, Mass. Lawrence Addicks, Douglas, Ariz. Francis R. Pyne, Elizabeth, N. J. W. F. Durand, Stanford Univ., Cal. George B. Pickett, Ophir, Colo. S. P. Cooper, New York, N. Y. R. V. Norris has been elected President of the Columbia School of Mines Alumni Association. Robert C. Sticht has been elected President of the Australian Insti¬tute of Mining Engineers.

Jan 6, 1915