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By Fred P. Dewey

In my paper on the porosity and specific gravity of coke, read at the Roanoke meeting, June, 1883, and published in this volnme, an analysis by Dr. henry Froehling is reported (p. 10 of the preliminary edition of the paper, or p. 120 of this volume), as showing the composition of Fire Creek coke. This analysis WaS of coke made in beehive ovens at Low Moor, Va., from New River coal. Dr. Froehlng's analysis of the Fire Creek coke was as follows: Moisture..........0.260 Volatile matter.........0.260 Fixed carbon .........92.377 Ash 1....6.750 Sulphur..........0.535 Phosphorus.........0.0146 Both analyses are reported side by side in The Erginias for 1883, p. 99. By an error in copying, the Low Moor analysis was trans-

Jan 1, 1884

By A. D. Hodges

In 1874 my attention was called to what seemed to me an interesting and new nickel and cobalt combination found in Ludwig and Carter's copper mine, near Mason Valley, Esmeralda County, Nevada. With the assistance of Mr. A. Hebberling I made several partial analyses of the mineral or minerals. I also communicated with my friend, Professor H. B. Cornwall, of the John C. Green School of Science, College of New Jersey, who analyzed a couple of specimens which I forwarded to him. The copper ore occurs in the mine principally as carbonate and to a certain extent as silicate, the latter generally in connection with clay seams or bands. In some places, together with the copper silicate and clay, generally interstratified with them, there occurred a compact shining black mineral (a) containing nickel and cobalt. Occasionally, in cavities, in connection with (a) was found a black substance (b), either massive and in this case very similar to (a) but with driller lustre, or forming an incrustation with rough and botryoidal surface and radial-fibrous structure, or granular and earthy. A few specimens were found having on the surface very fragile black needles (c) sometimes 1/2-inch long, interspersed with needles of malachite. The mineral (a) seemed, according to the analyses, to be of nearly constant composition, and was considered by Professor Cornwall to be a chrysocolla containing nickel and cobalt—a new occurrence to

Jan 1, 1885

By Bailey, Lewis Newton

Bailey, Lewis Newton, Master Engineer, Senior Grade, 4th Regiment, U. S. Engineers, Headquarters Company, died of pneumonia at Camp Merritt, N. J., on Apr. 30, 1918. Baird, Louis, Lieut., Royal Field Artillery, British Army, died on the battlefield in 1915. Ballamy, John H., Capt., 103d Engineers, killed in action near Fismes, Aug. 9, 1918. Bowles, Martin F., 2d Lieut., Co. B, 355th Infantry, killed in action, Sept. 3, 1918. Burt, Andrew, died in active service, 1916. Cobeldick, William Morley, Royal Engineers, died from gas poisoning on Oct. 7, 1915. Dougall, Ralph, 4th University Co., Princess Patricia Regiment, killed in action early in the war. Evans, Alfred Winter, Lieut.-Col., New Zealand Rifle Brigade, D. S. 0., D. C. M., killed in action on Oct. 12, 1917.

Jan 3, 1919

By G. W. P. Rengstorff

In an effort to find an oxidation-resistant alloy of molybdenum, binary and ternary alloys containing aluminum, chromium, cobalt, iron, nickel, silicon, titanium, tungsten, vanadium, and zirconium were screened. Fourteen other alloying additions were also tested. Many of the alloys were more oxidation-resistant than molybdenum, but none were entirely satisfactory. MOLYBDENUM oxidizes extremely rapidly above 1450°F in air. At 1800°F, a loss of metal at the rate of 0.1 in. in 4 hr is typical. The high speed of this oxidation may be judged by comparison with the oxidation rate of 0.1 in. per year (0.00005 in. in 4 hr), sometimes taken as the maximum permissible oxidation rate at 1800°F for a satisfactory Fe-Cr-Ni alloy. Great strides have been made in the development of coatings and cladding to protect molybdenum from oxidizing atmospheres. These developments in surface protection will undoubtedly make it possible to take advantage of the excellent hot strength of molybdellum and its alloys in many new applications. Still, even the best coating can protect molybdenum only as long as the surface layer is unbroken. Research was undertaken to determine whether an alloy of molybdenum could be found which would resist oxidation. Such an alloy would not deteriorate suddenly when the protective surface layer was destroyed in a small area. In seeking an alloy of molybdenum to resist oxidation, the physical properties of molybdenum could not be sacrificed entirely. The development of an alloy with the desired resistance to oxidation was not achieved. The information obtained on the effect of a large number of elements on the oxidation of molybdenum is, however, of value in the development of coatings. Indeed, many of the alloys tested for oxidation resistance were already known to have poor mechanical properties but were tested to aid in the development of coatings. Oxidation of Molybdenum The rapid oxidation of molybdenum is usually attributed to the volatility of Moo,,. Gulbransen and Wysong have shown that molybdenum oxidizes very slowly up to 850°F, the temperature at which the oxide film begins to evaporate. Melting as well as evaporation of molybdenum oxides promotes the oxidation of molybdenum. MoO melts at 1465°F. MOO, the oxide which is believed to form at the metal-oxide interface, combines with MoO, to form a eutectic having a melting point of 1432°F.' The liquid oxide, even if nonvolatile, could cause poor resistance to oxidation by allowing easy transport of molybdenum and oxygen ions through the oxide. Actually, a sudden increase in the rate of oxidation of molybdenum at 1460°F has been observed to coincide with the appearance of a liquid phase. The formation of a volatile oxide is not unique with molybdenum. The problem is also encountered with vanadium, tungsten, and some of the Pt-Pd group of metals. Vanadium not only forms the volatile V2O3 but, like molybdenum, forms a liquid oxide coating. Few attempts have been made, however, to prevent the rapid oxidation of these metals by alloying. Oxidation of Molybdenum Alloys At the beginning of this work, very little was known of the oxidation resistance of molybdenum alloys. It was known that molybdenum disilicide (with 37 pct Si) has extremely good oxidation resistance,' but this compound is so brittle that it has few uses. It is an effective protective coating for molybdenum when allowance can be made for its brittleness. Chromium was known to retard the oxidation of molybdenum,' but at least 50 pct Cr was necessary to have an appreciable effect. Other, unpublished, reports show that a few other alloys have been given preliminary tests, but the results have not been promising." Choice of Alloys to be Investigated An alloying element might be expected to protect molybdenum in either of two ways: Its oxide might combine with molybdenum oxide to form a stable, nonvolatile complex oxide (a molybdate); or the oxide of the alloying element might form in preference to molybdenum oxide, developing an impervious layer which would prevent the formation of a volatile molybdenum oxide. The knowledge available about the formation of molybdates was meager. Therefore, the initial study was made on alloys of molybdenum with elements having especially stable oxides. On this basis, binary and ternary alloys containing the following six elements were investigated: aluminum, chromium, titanium, zirconium, silicon, and vanadium. Nickel was also added as an alloying element. Although it does not form a more stable oxide than molybdenum, it does impart some oxidation resistance to copper and iron. Its inclusion in the study was fortunate because its alloys proved to be the most promising of those first tested. Apparently nickel formed a stable molybdate. Because nickel was effective in reducing the oxidation rate of molybdenum, the elements iron, cobalt, and tungsten were added to the list. The ten alloying elements mentioned form ten binary and 45 ternary alloying systems with molybdenum. A series of alloys was tested in each of these systems. In addition, at least one test was made on the effect of each of the following alloying elements:

Jan 1, 1957

On the following pages are abstracts of papers published by the Institute during the year 1932 as Technical Publications, Preprints, in bound volumes and in Mining and Metallurgy. For abstracts of papers that appear in bound volumes in 1932 but that were published as Technical Publications in 1930 or 1931, see the Transactions for those years. Papers that appear in this volume are not abstracted here. Many of the Technical Publications have been reprinted in bound volumes. Information regarding this disposition, and number of pages in each paper, may be found in the list beginning on page 309. Volume numbers are given as listed on page 3 and in the paragraph at the beginning of the index, page 315. The abstracts are grouped as follows: Page Page Metal Mining.................... 265 ferrous Alloys)................. 279 Milling and Concentration......... 268 Coal Division.................... 287 Iron and Steel Division............ 270 Petroleum Division............... 292 Nonferrous Metallurgy (Reduction Nonmetallic Minerals............. 299 of Ores)....................... 277 Mining Geology.................. 301 Rare Minerals and Metals......... 279 Mining Administration (Accounting, Institute of Metals Division (Found- Taxation, Industrial Relations). . 304 ing and Metallography of Non- Geophysical Prospecting........... 304 Metal Mining The Mineral Industry. By Scott Turner. (Min. & Met., June, 265. 3500 words.) Abstract of an address delivered before the Royal Canadian Institute, Toronto, April 16, briefly outlining the importance of mining in the United States, in Canada, and in the world. Comparison is made of the mineral production for 1886, 1900, 1910, 1920 and 1929, showing that in the 43 years from 1886 to 1929 that of the world increased nearly tenfold, of the United States over twelvefold and of Canada thirtyfold, but that Canada's output was equivalent to only 2 per cent of the world total and to 5 per cent of that of the United States in 1929. Statistical tables and graphs show value of production, percentage of world production contributed by Canada and the United States, etc. The mining situation in Canada is briefly reviewed: only those American engineers who have had occasion to examine the figures appreciate the rapidity of growth of Canadian mineral production. The treatment of minerals involves vast complex industries. When we are producing, say, 6 billion annually, the employment of 2 million workers provides indirect support to perhaps 10 million people. Exploiting mineral deposits is peculiar in certain ways, for the deposits are exhaustible, are of rare occurrence when measured in terms of outcrop area compared to total earth area, and may suddenly be handicapped or superseded by new discoveries; moreover, the economic position of the contained metals is 'affected by the use of scrap metal and the existence of invisible stocks. The largest and most valuable of the mineral deposits are not the metals, but rather the fuels. The record of the coal industry in recent years is one of brilliant technical achievement; its economic position is far from satisfactory. A so-called world fuel

Jan 1, 1932

By ANDREW CARNEGIE

Although the noble building provided in New York City by Mr. Carnegie for the United Engineering Society has been pushed to about half-completion, the ceremony of laying its corner-stone was not performed until Tuesday afternoon, May 8, 1906. The stone lies just back of the southeast corner of the building, on the north side-of West 39th Street. Among those present were Mr. and Mrs. Carnegie, Miss Whitfield, the sister of Mrs. Carnegie, Ralph W. Pope, Secretary of the Institute of Electrical Engineers, Frederick R. Hutton, Secretary of the. Society of Mechanical Engineers, Rossiter W. Raymond, Secretary of the Institute of Mining Engineers, Charles H. Haswell, the first Chief Engineer of the United States Navy (1836-1851), now in his ninety-seventh year, John Fritz, of the Bethlehem Steel Company, William H. Fletcher, President of the Engineers' Club, E. E. Olcott, President of United Engineering Society, and other interested friends. After an inspection of the interior of the building, the group formed about the corner-stone, which had been draped with the American flag. The exercises were opened by Mr. Olcott, who appropriately welcomed Mr. Carnegie, and briefly expressed the essential value of the building, saying, in part " The societies to be housed underneath this roof have as their aim the pre¬serving and putting in tangible form of the records of scientific accomplishments so as to avoid the repetition of mistakes. The possibility of finding the records of these results all at one center, so near the great Public Library of our city, will be an inestimable advantage to all professions. It is an occasion of no ordinary moment, therefore, when we can welcome Mr. Carnegie and have him lay for us the corner-stone of this great building which his liberality has provided." Mr. Carnegie responded in happy vein, thanking the committee for their greeting, and expressing his pleasure. in being able to do what he had done to further so worthy a cause. Among other things, he said

May 1, 1906

By Francois E. Heuze

INTRODUCTION Rock slope stability typically is governed by the geological discontinuities. This stability can be improved by drainage, unloading, adjustment in slope orientation, adjustment in slope angle, and also by reinforcement such as bolts or tendons. This paper addresses the modeling of bolt reinforcement in rock slopes. Most geological discontinuities such as joints have rough surfaces; they dilate during shear displacement. Their shear strength is characterized by two envelopes (Fig. 1); the peak envelope is distinct from the residual envelope when the joints can dilate. If the dilation is restrained transversely, such as with bolts, the normal stress will increase and the joint strength also will increase. It has been demonstrated that this increase may be considerable (Obert et al., 1976). The new normal stress at peak strength is a com- posite function of the properties of the rock mass and of the steel (Heuze, 1979). Hence, the dilation and its resultant effects on joint shear strength must be included in the analysis and design of the reinforcement. We present a model which can be used to perform such an analysis. Early studies of rock reinforcement in mining and civil applications (Lang, 1957 - Panek, 1962 - Osen and Parsons, 1966 - Lang, 19721, did not consider the specific effects of bolts on joint shear strength. In 1973, Heuze and Goodman reported direct shear tests on rough sandstone joints with bolts perpendicular to the joint plane (Fig. 2). The peak shear strength of such joints was greatly in excess of the shear strength of the unbolted joints. The excess

Jan 1, 1983

By G. Willard Quick

FAILURES in railroad rails have been of vital concern to engineers; railroad executives, rail manufacturers and the general public for years. Failures from transverse fissures originating from internal nuclei have received particular attention in the past 20 years. Dr. J. E. Howard first reported this type of failure in 1911, as being responsible for a wreck-on the Lehigh Valley R. R. in which several lives were lost. Since then many transverse fissures have been found. In 1919, Waring and Hofammann1 etched longitudinal sections of rails in hot acid and found cracks extending both longitudinally and transversely in certain used rails as well as in some new rails.. Since then it has been thought by many that these "shatter" cracks are the nuclei from which transverse fissures subsequently develop in service. Methods for reducing the rate of cooling rails on the hot. bed have been devised to decrease the temperature gradient and consequently the stress gradient in the rails. A study of the tensile properties of rails at elevated temperatures was made by Freeman and Quick,2 who investigated the properties at temperatures through which rails pass on the cooling bed after leaving the hot saw. In their investigation a special study was made of the ductility of the steels in the temperature range 400° to 700° C. In this temperature range it was found that certain rail and other steels showed a marked decrease in elongation and reduction of area. The phenomenon was called "secondary brittleness" and the temperature range the "secondary brittle range." A tentative explanation was presented that internal failure such as "shatter cracks" and "hair cracks" in rails are the result of thermal stresses developed in the steel structure while cooling through the secondary brittle range. The investigation showed that the magnitude of the phenomenon varies for different heats, but that it did not differ for specimens from different ingots or for different rails in a particular ingot. It was also shown that annealing rail steel at a temperature either above or below the critical

Jan 1, 1932

THERE can be little doubt in the mind of anyone of the great interest which has been provoked in the mining and petroleum industry by the com-paratively new geophysical methods of prospecting, after the sessions at this year's meeting of the Institute. Not only were the sessions very well attended but every¬one seemed most attentive. Although the discussion was somewhat limited in general, that may well be at-tributed to the newness of the subject. Two sessions on this subject were planned originally, but these gave insufficient time for the presentation of all the papers prepared and a third session was abso-lutely necessary. The first meeting dealt entirely with the gravity methods and was completed in the scheduled time owing to the fact that but two of the five papers listed were read. The second session was devoted to magnetic and electrical methods, the completion of which had to be carried over into the third period of geophysics. The first session on geophysical prospecting, and in-cidentally the first scheduled Institute meeting devoted entirely to this subject, was most appropriately opened by E. L. DeGolyer, the chairman of the session. It was through the efforts of Mr. DeGolyer that the first gravity work, as applied to prospecting, was under-taken in this country. Again most appropriately, the first paper presented was given by Donald C. Barton, who carried on the first work with the Eötvös torsion balance in America and aided materially in its development. A subject, the theory of which is so difficult to understand as it is generally presented, was so clearly illustrated and ex-plained by the speaker that even a novice could grasp the fundamentals. Dr. Barton, in showing actual re-sults obtained in torsion balance surveys with the in-terpretation of the sane and later drilling records, was free in stating that there are many limitations to the field in which this and the other geophysical instruments may be successfully employed. This paper called for considerable discussion relative to the application of the torsion balance to gravity surveys over various types of structures. During the course of this discus-sion a very important point was emphasized by the chairman, namely, that for successful application of any or all of the scientific methods of prospecting, a back-ground of experience is absolutely necessary to serve as a basis for further work. This can only be secured by contributions from the results of actual prospecting work.

Jan 3, 1928

By David White

The submission of carefully prepared estimates of the oil reserves of the United States calls for no apology or explanation. In this country, petroleum is a rapidly wasting asset and an occasional appraisal of the amount remaining in the ground is a simple business procedure to safeguard the general welfare and the prosperity of the republic. The rumored danger of failure, in the near future, of the foreign supply on which we depend in constantly increasing amounts makes the immcdiatc review of our available reserves the more imperative. The Director of the U. S. Geological Survey, in March, 1921, requested the American Association of Petroleum Geologists to cooperate in the preparation of new estimates of the oil remaining in the graund. With the members of this cooperative committee, state geologists, regional geologists, oonsulting specialists, and geologists and engineers attached to many companies worked both independently and through subcommittees. The reports for districts, counties, fields, etc., after review by local or state committees, were discussed by the joint cooperative committee in conferences that, in some instances, were attended by the original compilers of estimates for the states or smaller areas. Finally the data were reviewed and the figures revised by the joint cooperative committee, so that the totals given in Table 1 represent the opinion of the committee, which was composed of F. W. DeWolf, W. E. Wrather, Roswell H. Johnsont Wallace A. Pratt, Alexander W. McCoy, Carl H. Beal, C. T. Lupton, G. C. Matson, K. C. Heald, W. T. Thom, Jr., A. E. Fath, Kirtley F. Mather, R. C. Moore, and David White, chairman. Oil geologists and engineers understand well the speculative nature and the chances of error that must attend estimates of the petroleum in the ground when they cover not merely prospective territory, but possible territory. Neither the character nor the magnitude of the factors of uncertainty is to be disguised. Further, the inevitable differences of opinion between geologists of equal rank and experience must also bc

Jan 1, 1923

By David White

The submission of carefully prepared estimates of the oil reserves of the United States calls for no apology or explanation. In this country, petroleum is a rapidly wasting asset and an occasional appraisal of the amount remaining in the ground is a simple business procedure to safeguard the general welfare and the prosperity of the republic. The rumored danger of failure, in the near future, of the foreign supply on which we depend in constantly increasing amounts makes the immcdiatc review of our available reserves the more imperative. The Director of the U. S. Geological Survey, in March, 1921, requested the American Association of Petroleum Geologists to cooperate in the preparation of new estimates of the oil remaining in the graund. With the members of this cooperative committee, state geologists, regional geologists, oonsulting specialists, and geologists and engineers attached to many companies worked both independently and through subcommittees. The reports for districts, counties, fields, etc., after review by local or state committees, were discussed by the joint cooperative committee in conferences that, in some instances, were attended by the original compilers of estimates for the states or smaller areas. Finally the data were reviewed and the figures revised by the joint cooperative committee, so that the totals given in Table 1 represent the opinion of the committee, which was composed of F. W. DeWolf, W. E. Wrather, Roswell H. Johnsont Wallace A. Pratt, Alexander W. McCoy, Carl H. Beal, C. T. Lupton, G. C. Matson, K. C. Heald, W. T. Thom, Jr., A. E. Fath, Kirtley F. Mather, R. C. Moore, and David White, chairman. Oil geologists and engineers understand well the speculative nature and the chances of error that must attend estimates of the petroleum in the ground when they cover not merely prospective territory, but possible territory. Neither the character nor the magnitude of the factors of uncertainty is to be disguised. Further, the inevitable differences of opinion between geologists of equal rank and experience must also bc

Jan 1, 1923

By Leonard C. Grimshaw

The idea of bonding two dissimilar ferrous metals, and making use of both, is an old one. Tips have been brazed onto tool shanks for many years. The bonding of larger pieces to form whole bars and sheets has also been accomplished, but has received little attention in the technical literature, although a number of patents have been issued covering various methods for its accomplishment. There are three main motives behind the manufacture of composite steels. One is that the physical properties of one steel may supplement those of another; a useful, but at the same time, hard, brittle steel may be backed by a soft ductile one, or a stainless steel may be backed by a steel possessing greater strength. Another motive is direct lowering of cost; an expensive steel may be backed by a less expensive one, bringing down the cost of the piece as a whole. The third motive is an indirect lowering of cost, as when a useful steel is backed by a steel that is easier to machine, so that machining cost on a finished product is lowered considerably. Often more than one of these motives lead to a decision to use a composite steel. Previous Methods There are two methods in use that result in tolerably good bonds between ferrous metals: (1) the casting method, and (2) what we shall call the "heat-pressure" method. This "heat-pressure" method covers processes in which the bond is made between two prepared surfaces by heating them and then applying pressure. Usually sufficient pressure must be used to produce appreciable spread and elongation, or else we arc merely brazing and not truly welding. Casting methods for welding together ferrous metals have been used more than 74 years, and are described in the technical literature as applied

Jan 1, 1936

By Leonard C. Grimshaw

The idea of bonding two dissimilar ferrous metals, and making use of both, is an old one. Tips have been brazed onto tool shanks for many years. The bonding of larger pieces to form whole bars and sheets has also been accomplished, but has received little attention in the technical literature, although a number of patents have been issued covering various methods for its accomplishment. There are three main motives behind the manufacture of composite steels. One is that the physical properties of one steel may supplement those of another; a useful, but at the same time, hard, brittle steel may be backed by a soft ductile one, or a stainless steel may be backed by a steel possessing greater strength. Another motive is direct lowering of cost; an expensive steel may be backed by a less expensive one, bringing down the cost of the piece as a whole. The third motive is an indirect lowering of cost, as when a useful steel is backed by a steel that is easier to machine, so that machining cost on a finished product is lowered considerably. Often more than one of these motives lead to a decision to use a composite steel. Previous Methods There are two methods in use that result in tolerably good bonds between ferrous metals: (1) the casting method, and (2) what we shall call the "heat-pressure" method. This "heat-pressure" method covers processes in which the bond is made between two prepared surfaces by heating them and then applying pressure. Usually sufficient pressure must be used to produce appreciable spread and elongation, or else we arc merely brazing and not truly welding. Casting methods for welding together ferrous metals have been used more than 74 years, and are described in the technical literature as applied

Jan 1, 1936

Mining Methods LUCIEN EATON, Chairman GERALD F. SHERMAN, Vice-chairman CHARLES W. WRIGHT, Secretary Alluvial Mining CLINTON BERNARD CHARLES H. MUNRO CHARLES JANE N H. R. NORSWORTHY Open-cut Mining Iron MAX H. BARBER J. A. MacKILLICAN Copper MICHAEL CURLEY H. B. TEMPEST Underground Mining Iron C. H. BAXTER CARL BREWER TENNEY C. DESOLLAR Copper W. B. DALY A. H. WOHLRAB R. W. THOMAS

Jan 1, 1934

By F. P. Haver, M. M. Wong

When a mixture of chalcopyrite concentrate and lime is heated in air, the following reaction takes place: 2CuFeS2 + 4Ca (OH)2 + 8 ½ 02 ; 2Cu0 + Fe203 + 4CaS04 + 4H20. Ca (OH)2 is the only common reagent that will adequately control SO2 evolution in roasting. Other additives tried, including CaO, CaCO3, Na2CO3, NaOH, MgO, Mg (OH)2, and MgCO3, were not effective. All reacted with sulfur, but not to the extent that will be required to meet the new control regulations for sulfur oxide emissions. For example: when the concentrate was heated with the theoretical amount of limestone (CaCO3), about 55% of the sulfur was retained in the calcine; whereas use of the stoichiometric amount of Ca (OH), converted approximately 99% of the sulfur to CaSO1. In most of the experiments, Ca(OH)2 was formed by adding CaO to concentrates containing enough water to simulate filter cake from flotation circuit. This eliminated the need for drying the concentrate and utilized the heat of hydration of CaO.

Jan 6, 1972

The Johns Hopkins Press, Johns Hopkins University, Baltimore, Md The Johns Hopkins Press has issued a number of books as The Johns Hopkins University Studies in Geology Five of the studies are paleontological in character; five are on geology: No. 1, The geology of the Corocoro copper district of Bolivia, by J. T Singewald, Jr and E W. Berry, $1 50, 2, The geology and paleontology of the Huancavehca mercury district, by E W Berry and J T Singewald, Jr $1 50, 6, Contributions to the geology and paleontology of South America, by E W. Berry and F M Swartz, 3175, 7, The geology of the Island of Trinidad, B W I, by G A Waring, with notes on the paleontology by G. D Harris, $1 75, 8, Fifty years' progress in geology, 1876-1926 Papers presented at the Geological Conference during the 50th Anniversary of the Johns Hopkins University, $1 50 An additional publication on geology is. Notes on the minerals occurring in the neighborhood of Baltimore, by G H Williams, 25 cents. In the list of Doctors' Dissertations available from the University are found all theses on geology and mineralogy, about 90 in number, from 1886 on Authors of many of these have since made great names for themselves in the fields of geology and mineralogy. Most of the theses have been published as papers by other agencies and, as such, will be found under other headings in this directory

Jan 1, 1933

[United Engineering Society WALTER H. ALDRIDGE J. VIPOND DAVIES J. V. N. DORR Engineering Societies Library Board SYDNEY H. BALL ALEXANDER C. HUMPHREYS GEORGE C. STONE JOHN H. JANEWAY Engineering Foundation Board H. M. BOYLSTOX J. VIPOND DAVIES GALEN H. CLEVENGER]

Jan 1, 1928

By W. R. Shimer

(New York Meeting, October, 1913.) THE investigation herein described was carried out for the purpose of studying, both by chemical and metal-lographical means, the extent of over-oxidation of steel that can be accomplished by excessive over-blowing in a Bessemer converter. In addition there are appended some results of basic. open hearth and crucible steels. Remarks on Chemical Methods. The test block used was hemispherical in shape, 4.5 in, in diameter and 2 in. thick. Drillings for analysis were obtained by drilling through the entire solid part of the. block, carefully avoiding all cracks anti blow-holes and mixing these drillings thoroughly. Drillings were carefully examined for scale and the finest were gone over with a microscope to be sure all scale from whatever source had been. removed. Oxygen was determined by the well-known method of Ledebur, modified according to Cushman,1 with, however, the removal of the preheating tube, which was found unnecessary. This method has been found to give concordant results. Blanks run from 0.0003 to 0.0006 g. Duplicate determinations varied not more than 0.001 to 0.003 per cent. It seems to be generally supposed that the hydrogen method gives only that oxygen which is combined with iron. Whether this be true or not, the content of oxygen existing as iron oxide no doubt predominates sufficiently, so that the result obtained is sufficient to indicate whether the steel is over-oxidized or not.

Jan 9, 1913

By H. M. Hobart

This paper deals principally with investigations undertaken by the Welding Research Sub-committee of the Welding Committee of the Emergency Fleet Corporation. The general object of the investigations has been to extend the use of welding in the construction of merchant ships and, specifically, to provide a definite basis for obtaining the greatest economy and efficiency in employing welding in place of riveting in the construction of the hulls of such ships. Composition of_ Ship-plate Steel The chemical composition of the steel employed in such hull construction varies with the thickness of the plates. Through the courtesy of Mr. H. Jasper Cox, of Lloyd's Register of Shipping, the following information may be given concerning the kind of steel plate employed in American shipyards in 1918 for the hull construction of merchant ships. Lloyd's requirements do not relate to the chemical composition. They require a tensile strength of 58,000 lb. per sq. in. (40.75 kg. per sq. mm.) for their lower limit and 72,000 lb. per sq. in. (50.59 kg. per sq. mm.) for their upper limit. For the information of the Committee, Lloyd's obtained from their surveyors at various works data of the carbon content, which is as follows: Works Carbon Content for Plates 1/4 In. Thick 1 In. Thick A..................... 0.14 0.23 B..................... 0.14 0.25 C2.................. 0.19 0.25 D................. 0.20 0.30 E Upper limit..... 0.35 Lower limit..... 0 24 0.29 Upper limit,.... 0.25 0.30 Lower limit..... 0.21 0.27 Upper limit..... 0.25 0.35 Lower limit..... 0.22 0.28

Jan 1, 1920

By W. A. STERLING

IN the opencut iron mines of the Mesabi Range in Minnesota, the trend in mining is in the development of mining equipment and mining methods which will move surface overburden and ore-bearing materials with less labor and at a cheaper cost. This is a must for most of the independent operators. Their reserves of direct-shipping ore are extremely small and their operations are being conducted in small, or intermediate pits, with a high stripping ratio in the outer fringes, or shore lines of older pits. and in ore bodies passing from direct shipping to the washing and the intermediate, or retreat ore state. The trend is toward deeper stripping, longer and steeper hauls, and the necessity of moving a total of from three to five or six tons of overburden and ore material for each ton of shipping-grade ore produced. This naturally calls for greater production, with larger shovels, or draglines. cheaper drilling and blasting costs through the drilling of larger-diameter blastholes, and cheaper haulage through the use of trucks of larger capacity and more extensive use of belt-conveyor systems. This trend is notable both in stripping and mining.

Jan 1, 1948