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By J. E. Metcalfe

Proceedings of the Fourth Empire Mining and Metallurgical Congress, Great Britain 1949. Part II published at the Offices of the Congress in London, England, 1139 pp. The price of these proceedings is £ 2. The parts may be purchased separately at a cost of £ 1 each.-Part I of this book covers a report of the organizing committee, the inaugural meeting and presidential address, banquet at Guildhall, welcome by Sir Richard Livingstone at Oxford. and final session. Technical session and papers are also covered in Part I. Part II covers such topics as coal, present-day trends in mineral dressing and metallurgy. Mining Engineer's Survey Manual. By J. E. Metcalfe. Published for "Mine & Quarry Engineering" by Electrical Press, London, 1951. 341 pp., illus., charts, diagrs., tables, 8 ¾ x 5 1/ in., cloth, 30s., available from Percival Marshall & Co., Ltd., London, and British Book Centre, 122 East 55th St., New York 22, N. Y. Beginning with a brief treatment of surveying fundamentals and a discussion of the correlation of surface and underground surveys, this practical manual continues with descriptions of surveying practice both above and below ground including stopes, inclined shafts; etc. Space is devoted to sampling and valuation, geological considerations, and descriptions of modern surveying instruments. The organization of survey operations is covered in the last chapter.

Jan 1, 1952

Jan 1, 1894

By George L. Porter

Mr. President and Gentlemen of the Institute of Mining Engineers: . Unofficially representing the people of the vicinage, it is my pleasant duty to welcome you to the city of Bridgeport, to the valley of the Naugatuck, to the State of Connecticut. The importance and wide-reaching influences of the investigations for which your Institute is organized, the beneficial results which have directly and indirectly blessed mankind from your and kindred studies, the distinguished position which has been achieved in the scientific world by the Institute as a society, and the personal reputation which is the proper recognition of the ability and knowledge of its individual members, assure all that in attempting to honor you we are ourselves honored. In the republic of knowledge no fictitious rewards dignify the incompetent and the ignorant—the attested success of inventions and discoveries in the workshop of nature differentiates her real citizenship. Your present place of meeting is wisely selected ; for this senti-

Jan 1, 1895

By Rossiter W. Raymond

The substance known as carbonite, or natural coke, has been several times the subject of comment before the Institute. The most important contribution hitherto made to the discussion is that of Dr. Henry Wurtz, of Hoboken,* who states, upon the strength of a chemical analysis, that carbonite is not a coke, but contains 14.08 per cent. of volatile combustible matter. In 1882 a mine was opened upon a carbonite seam, near Midlothian, Chesterfield County, Va., by Messrs. Jewett & Brother, of that place. The seam, which dips westerly at an angle of about 30 degrees, was struck at the depth of 137 feet with a vertical shaft, and followed on the dip 325 feet, at which depth gangways were opened north and sooth. For these statements (having made no personal examination of the locality), I am indebted to Mr. Albert Blair, of Richmond, and for the following section, to Mr. John Bladon, engineer at the mine. The section was taken in the face of the gangway, February 17th, 1883. It shows an aggregate thickness of 15 feet of "coke," of which about 5 feet were extracted by the system employed last winter. It is reported that under the "coke" seam there is a thick seam of highly bituminous coal, which has been extensively worked on a neighboring property, a little south of the Jewett colliery, the coal being sold for gas-waking. The carbonite is used for domestic purposes, and is said to burn

Jan 1, 1883

By R. R. Morral, F. M. Krill, K. T. Aust

THE occurrence of twins in aluminum ingots cast under certain conditions has been well established. For instance, Herenguel and Lacombe1,2 have observed a twinned columnar structure in 99.5 and 99.9 pct Al, solidified by continuous or semicontinuous casting. The structure, which they termed "basaltic," appears in the form of elongated crystalline fibers of alternating luster. Herenguel and Lacombe2 found sections of flat crystalline plates composed of twin crystal plates, in which the twin plane (111) and a [I121 direction contained in the twin plane are parallel to the principal heat gradient. This orientation relationship is different from the usual orientation texture observed in cast face-centered cubic metals, where the [100] direction is approximately parallel to the long columnar axes lying in the direction of growth." A large amount of twinning has also been observed by the present authors in semicontinuous cast aluminum of 99.2 pct purity, Fig. 1. Mondolfo4 has suggested that the twinned cast structure forms by a deformation twinning process as the result of uneven cooling stresses within the ingots. This suggestion appears to be inconsistent with the large amount of twinning observed in the semicontinuous cast ingots and with the large difference of dendritic

Jan 1, 1953

By John W. Bader

Probing a mineralized area with a core drill to find out what's there is fundamentally a simple task, but a costly one. Quite commonly it costs $10, and sometimes more, to extract and assay each foot of drill core obtained. Yet, it is not unusual today to drill hundreds of holes on one mineral property. The initial objective of such probing is almost always simply to determine the potential worth of the ore- body, if any exists, and the question naturally arises: How little sampling is enough for this determination? The mathematics of statistics infer accuracy of estimates largely from the sheer number of samples taken. Mineral exploration usually involves accumulation of large numbers of samples, and thus it is usually not difficult to place narrow confidence limits on either side of the estimated average grade of a sampled orebody. The determination may, or may not, be as accurate as the derivations imply. If it is not, the fault is probably one of misapplication and not with the statistical processes themselves. Un- fortunately, indications are strong that the ordinary statistics of sampling usually cannot be applied to orebody exploration samples with actual attainment of the accuracy of estimate that they express mathematically. For this reason, a more deductive, less mathematical analysis of the sampling may well be worthwhile.

Jan 1, 1970

By Ramkrishna Agarwal

The problem of the measurement of in situ stresses in rock masses has, in recent years, become one of the prime concerns of investigators and researchers in the field of rock mechanics. Numerous instruments have been developed for that purpose and various techniques have been used to determine the absolute values of these stresses at a point.l The "stress-relief" technique has gained the widest acceptance. In its usual application it relies on one of the two following principles: (1) Measurements of the changes in a "solid inclusion" in a borehole,2 or (2) Measurements of the diametral deformation of a borehole with a free boundary." The theoretical development, in the case of the latter, is based upon an evaluation of the deformation of a circular hole in an infinite plate under the action of a uniaxial stress field. Expressions for the deformations may be obtained by using either the plain strain or the generalized plane stress theoretical approach of the classical theory of Elasticity, which assumes that the material is linearly elastic, homogeneous and isotropic. The solution for the case of a biaxial stress field is obtained by the Principal of Superposition. The circular hole becomes elliptical after deformation takes place under the action of a uniaxial or biaxial stress field applied to the plate. In the practical application of the technique, the reverse procedure is applied. A borehole is drilled in the rock and a deformation-measuring

Jan 1, 1968

By Benjamin B. Lawrence

Arthur Launcelot Collins was born at Truro in Cornmall, England, July 8, 1868. His father, J. H. Collins, is well kuown as an engineer, and his books have been widely read in this country: Arthur was the third son. Three of his brothers are engaged, as is his father, in the profession of mining engineering. His education, gained partly at St. Austell, partly at Falmouth, and partly at Nuttall's Collegiate School in Truro, England, was supervised by his father, who was then Lecturer on the Mining Sciences to the Miners' Association of Cornwall and Devon. In 1881, J. H. Collins went to Rio Tinto, in Spain, as chief chemist and metallurgist, and it was there that Arthur began his practical work in the laboratory and continued his studies in chenlistry and mineralogy. To the latter science he was deeply attached; and he never lost an opportunity of adding to his cabinet of minerals, of which he was an ardent collector. In 1883, he became assayer and general assistant to Mr. Nicol, Manager of the Peña del Hierro copper-mines, ncar Rio Tinto. Until 1885 he was associated with his father in the study of the geology of the Rio Tinto belt. In 1885 he retuined

Jan 1, 1904

Jan 1, 1942

Jan 1, 1939

By F. Julius Fohs

WITH portions of two coal basins within its borders and a few scattered fields already developed, the question arises: What is the future of Ken-tucky as an oil-producing State? Is the long list of failures due to lack of 'commercial pools, or unintelligent prospecting? A study of its beds and irregularities of structure points not only to a large waste of development money on unpromising areas, but also to the presence of a few structures well worthy of development. The surface rocks of Kentucky show in succession more than 4,000 ft. of Paleozoic sediments and more than 2,000 ft. of Cretaceous, Tertiary, and more recent deposits. Folding and erosion have brought these beds to the surface, where they have been observed and studied: in detail by my associate, James H. Gardner, myself, and others. This has given opportunity to observe the beds offering suitable reservoirs and having the proper impermeable covering; also the mapping of outcrops and outcrop lines, taken in conjunction with available well records, indicates that certain areas are worth testing, and with even greater definiteness shows areas which should be excluded, as devoid of possibilities. West of the Tennessee River, Cretaceous, Tertiary, and Quaternary sediments occur so that all trace of ancient folding is obliterated, the sediments overlapping unconformably Mississippian rocks. This area embraces 2,000 square miles, or one-twentieth of the area of the State, the Paleozoic rocks covering the remainder. Since there is nothing upon which to base the location of tests for oil and gas in the Cretaceous-Tertiary beds of Kentucky, the Paleozoic area will be chiefly considered.

Jan 3, 1915

The Library of. the above-named Societies is open from 9 A.M. to 9 P.M. on all week-days, except holidays, from September 1 to June 30, and from 9 A.M. to 6 P.M. during July and August. The Library contains about 55,000 volumes, including sets of technical periodicals and the publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library can render valuable service through correspondence; letters requesting information will receive special attention. The Library is prepared to furnish references and copies of articles on mining, and metallurgical subjects; to determine the existence of mining-maps, and to furnish general information as to the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. The members of the Institute can be of service to the Library by forwarding copies of mining-reports, maps privately issued, and similar material, which will be classified, indexed, and made available to other members. Suggestions for additions to the Library, either by purchase or personal solicitation as gifts, will be welcomed. It is hoped that members while in the city will use the Library freely, and assurance is given that most careful service will be rendered to them.

Jan 1, 1914

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

THE present study is intended as a preliminary statistical survey of the world's production of petroleum substitutes. The information presented is admittedly deficient. It is believed, however, that the increasing importance of these substitutes, particularly with Europe at war, justifies its presentation at this time, if for no other [ ] reason than to encourage enlightened pertinent discussion. The world's production in 1939 of petroleum substitutes-of which approximately 97 per cent are direct substitutes for motor fuels-is tentatively estimated at 108,000,000 bbl., or equivalent to the combined output of crude oil in 1939 of Rumania, Mexico and Colombia. With few exceptions, these figures of production represent also actual figures of consumption. The United States, owing mainly to its output of natural gasoline, leads all countries in the production of these products, with about 53 per cent of the total. In European countries, particularly Germany, the imminence of war in 1939 forced an increase in production and improvement of methods of manufacturing motor fuels, largely from coal, with the result that this country produced in that year over 20,000,000 bbl. of substitutes. Since the beginning of hostilities, substitutes have offered more and more the means of meeting the unfavorable balance between supply and demand in European [ ] countries; the increase in production of these products being at least in part offset by the systematic bombing of synthetic plants and oil storage. The source materials and the resulting substitutes are listed in Table I. The following are the approximate gross heat equivalents of some substitutes to barrels of gasoline:

Jan 1, 1941

By W. C. Schafer

In tunneling or mining where hydraulic shields, moles, or rock boring equipment is used lasers such as those shown guide the production machine by providing a continuous and visible line and grade reference. In this application the laser may be mounted in the heading, preferably somewhere above spring line. If we view the circular heading as a compass in the vertical plane with 0º referencing at the crown of the heading and 180º on the invert, then it might be said that the laser may be mounted anywhere from 270º through 0º to 90º. The laser is generally mounted 2 to 3 ft off the wall or the crown of the heading by means of a bracket that may be attached directly to the liner plate. In cases where no liner plate is used, then brackets may be bolted directly into the ribs, or grouted directly into the rock. Once the laser is in position the beam is projected to the face. Two points must be surveyed upstream between the laser and the face which define line and grade. Targets may be suspended beneath each of these points approximately 2 to 3 ft. These targets may be circular or rectangular with a surface area which approximates 16 sq in. Each of these two targets should have a ½ to ¾ in. hole drilled directly in their center. When the laser is adjusted so that the beam passes through the holes in each of the two targets, the laser beam itself will parallel the center line of the tunnel and become a visible line and grade reference over the total beam projection.

Jan 1, 1970

By J. R. CAIN

SAMUEL L. HOYT, ? Nela Park, Cleveland, Ohio (written discussion?). The work that Dr. Cain is doing on gases in steel should have a highly important bearing on investigational work in connection with steel-making practice. We found, for example, in our work in connection with the use of manganese in open-hearth practice that we needed expressions for the manganese efficiency and the "condition" of the steel. To get these figures we assumed that we would need to know the amount of FeO at different stages of the heat and the amounts of the gases present. This required simultaneous analyses of our samples for FeO and the gases and Dr. Cain seems to be the only investigator who has considered the analytical work from this point of view. That he has done so is very encouraging and it is to be hoped that his work will solve the mys-teries now surrounding this neglected phase of steel metallurgy. Those interested in the Ledebur method for use in connection with the efficiency of manganese as a "deoxidizing " agent will he disappointed to learn that more recent work at the Bureau indicates that Ledebur determinations are not reliable. The principal source of error seems to be due to the partial reduction of the ferrous oxide by the carbon present in the steel. However, it seems like an unnecessary criticism of the Ledebur method to state (p. 1319) that it proved of little value because it showed little differences in oxygen for a series of steels treated with ,various reagents and showing variations in physical properties and free-

Jan 12, 1919

(Butte Meeting, August, 1913.) IN metallurgical circle it is. known widely, but somewhat vaguely, that the ease of reduction of metallic .oxides. depends largely on the way they have been prepared. It is likewise known that. different forms of carbon have different and greatly varying reducing powers. It is the purpose of, this paper to show somewhat more definitely and scientifically these facts. Sonic years ago the writer published an account of pyrometric determinations of the reduction temperature of zinc oxides variously prepared and of several kinds.1 In said paper it was shown that the temperature at which zinc oxide evolves zinc according to the equation, ZnO+C? Zn+CO depends upon the nature of -the two reacting bodies. The determinations bad a range of accuracy of from 2°to 6°C.,whereas differences were found to, amount to an extreme of 90° C. So the differences are real ones and must have a definite cause. The equation of boiling water, (H2 O)4 = 4 (H20) has a fixed temperature for? equilibrium of 100° C. at 760 mm. pressure. In general, all equations reacting in the liquid or the gaseous phase have well-defined constant physical conditions which govern the equilibrium point and reaction velocities.

Jan 7, 1913

The Institute conducts jointly with the American Society of Civil Engineers, American Society of Mechanical Engineers and American Institute of Electrical Engineers, certain activities as listed below, and is joint owner with them of certain properties. United Engineering Trustees, Inc. When Mr. Carnegie made. his gift ?for the erection of a suitable home? for the engineering societies,

Jan 1, 1943

By Persifor Frazer

The section along the left bank of the Susquehanna, in Lancaster County, from Falmouth to the Maryland line, which the writer made in 1877 to accompany his report on that county, was redrawn by Professor Lesley, as stated in the prefatory'letter to Vol. CCC. (p. x.).* As then stated, neither the numerous data, nor the general features of the structure obtained by the writer, were changed ; but enough was done to make a discrepancy between the text and the section as given; and some important points were made less clear in the published section than they were in the MS. map. Amongst other portions of the section, that between the railroad stations, 1190 to 1224, gives the impression on the published maps of a much too definite superposition. A few words will be devoted to this region in the following communication. There is absolutely no room to doubt the structure for about four miles on .each side of the Tocquan axis. The dips are gentle, and in opposite directions, and the lithological characters constant within ordinary limits of variation, nor do these characters resemble those of the rocks which flank these gneisses and mica schists to the northwest and the southeast. For the same reasons it is evident that the rocks which occur within these eight miles or so, represent an horizon below the basement of the fossiliferous or palaezoic series. Not only have no fossils been found, but their lithologieal characters are unmistakably eozeic. But on the upper and lower margins of this

Jan 1, 1884

By Charles P. Williams

THE determinations of the specific gravities of a number of samples of lead produced in Missouri, which form the subject of this note, were undertaken with the view of ascertaining if any approximation to the purity of such leads could be reached in this manner. The results would seem to indicate that, whatever value the method may have in the case of the crude and more impure

Jan 1, 1877

By L. Delatour, K. Voltaire

This paper presents various aspects of the legal and economic settings that govern the exploration for mineral resources in Haiti.

Jan 1, 1980