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By Edward Schuster, Frank Feuille

As the time allotted is short, we can present only a general idea of the oil laws in the Latin-American republics, as a supplement to Bulletin 206 of the Department of the Interior compiled under the direction of J. W. Thompson of the Bureau of Mines and entitled "Petroleum Laws of All America." We shall not discuss the European colonies in Latin-America nor the island republics. As to the countries discussed, we shall attempt to give the main features of such special petroleum legislation as has been adopted prior to the early part of this year; where no special petroleum laws exist, we must look to the mining codes for light on the petroleum policy. As the laws and regulations for the extraction of the metals are often difficult of application to, and are lacking in many essentials for, the petroleum industry, it is best for persons or companies desiring to enter, on a large scale, into the petroleum exploration and development of countries not having special petroleum legislation, to obtain a concession contract from the executive of the country under consideration, and to have the concession approved by the congress. If this concession, which would then be a special law, contains nothing contrary to the constitution of that country and does not infringe on vested rights of third parties, it should be reasonably safe. If in such country there is some doubt as to whether the petroleum subsoil is owned by the nation or the private surface owner, only public lands should be covered with the concession. Guatemala is the only republic in the group that discriminates directly against foreigners. Bolivia, Ecuador, Mexico and Venezuela require waivers of diplomatic protection.' Colombia requires foreigners to agree to be bound by its alien law. In addition,Mexico makes it unlawful for foreigners to acquire direct ownership of real estate, including mines, within a zone of 50 km. along the coasts and one of 100 km. alongitsland

Jan 1, 1923

By Charles Clayton

CAST-STEEL runners, while not interesting from a commercial standpoint, furnish valuable material for microscopic study. Foley1 found not only the usual ingot structure, but zones of Widmannstattian structure, which he explains as due to differential crystallization. The writer, in examining nickel-steel runners, found a type of pro-eutectoid ferrite that is unusual and most probably new. The runner in question was 8.75 cm. (3.5 in.) in diameter and analyzed at its center 2.69 per cent, nickel and 0.350 per cent. carbon and at its edge 2.62 per cent. nickel and 0.359 per cent. carbon. The macrostructure, which is the usual type, is shown in Figs. 1 and 2, which are a cross-section and the longitudinal surface, respectively. Slight segregation of ferrite can be seen near the center of the segment and at other points near the edges of polyhedral grains. Stead's reagent brings out the dendritic structure within the grains as shown in Figs. 3 and 4. This texture is what would be expected of such a steel. Figs. 5 to 10 show the peculiar swirls of pro-eutectoid ferrite, the finding of which prompted this paper. These swirls, or eddies, if such a term can be applied, occur in all parts of- the runner and in all parts of the individual grains. I he tipper left-hand figure shows this ferrite at a grain boundary; the middle left-hand figure shows the inner portion of a grain; and the lower left-hand figure shows these swirls at the edge of a grain which is also the outer edge of the runner. Straight-lined ferrite associated with swirls is found in the areas of Figs. 11 and 12. The texture of the carbon-bearing constituent of the runner is shown to- some extent in Fig. 12, the pearlite being very fine or sorbitic. Higher magnification does not bring out any new features either in the peculiar ferrite or in the pearlite. Figs. 13 and 14, at 240 diameters, show the curved and straight-lined ferrite.

Jan 3, 1920

By Oliver Bowles

DELICATE PLANTS are now put to bed for the winter under glass-wool or rock-wool blankets. Thus arise new and unexpected uses for non-metallic materials and rocks and, at the same time, certain unique uses are fading out; for instance, the Italians have taken steps to bar the use of salt for money in Ethiopia. Novel sources of supply find a place in the record of recent achievements as exemplified in the migration of the frontiers of industrial mineral exploitation beyond the land area of the earth to include the ocean. Salt, of course, has been recovered from the sea for years but the treatment of enormous quantities of sea water for bromine has lately added to the importance of the ocean as a reservoir of mineral wealth. Increased use of non-metallic minerals in the commercial and economic life of the country is reflected in the wide scope and activity of the Industrial Minerals Division of the Institute. The outstanding recent achievement of the Division is the publication of a 955-page volume on industrial minerals and rocks, comprising 48 commodity chapters each written by an authority on the subject.

Jan 1, 1938

By Robin P. Gardner

A radioisotope tracer method combined with a suitable back-calculation method is proposed and evaluated for the determination of model simulation parameters in open-circuit continuous ball mills. The method essentially consists of using impulse and/or step injections of short-lived radioisotopes of the naturally occurring trace elements manganese and sodium. It is evaluated here on the basis of the minimum standard deviations of the product weight-size distributions. These minimum standard deviations are taken as those predicted by a Poisson distribution of the number of particles present in size fractions of the samples taken for analysis. Previously developed tanks-in-series lumped parameter models are used in the evaluation. The results indicate that the method is very promising.

Jan 1, 1976

GENTLEMEN : Herewith are transmitted the reports of your Treasurer and the Chairmen of your standing committees on Admissions, Membership, Papers and Publications, and Library for the calendar year 1931. To these reports you are referred for further details of the year's activities. Finances.-Depressed industrial conditions prevailing throughout the year were reflected in a substantial decline in current revenue. Aside from interest on sundry special funds (but including that from the Life Membership, Library, and General Reserve Funds) total receipts amounted to $168,274, compared with $194,636 in 1930. The principal items of decrease were $17,000 in advertising income from the monthly magazine MINING AND METALLURGY, and about $9,600 in dues and initiation fees. Of this shrinkage $4,000 is accounted for by decrease in the number of new members enrolled; and $5,600 by diminished income from current dues and arrearages. This naturally has coincided with an \ increase in delinquency and "drops" or suspensions for nonpayment of dues. The decline in advertising income, amounting to 38 per cent as compared with that of 1930, in general paralleled the experience of all technical and trade publications; and it is problematical whether 1932 will show as large a return from advertising as did 1931.

Jan 1, 1932

By S. B. Christy

Jan 1, 1902

By M. V. Nevitt

THE Cr,O-type, or P-tungsten, structure having the space group (Oh2— Pm,n) is one of the most widely occurring structures found among the intermediate phases involving transition metals. Including the phases reported here for the first time, the total number of these A,B phases now known is 39. Greenfield and Beck' have correlated the lattice parameters of these phases with the Goldschmidt radius of the close-packed chains of A atoms. Laves' discussed the apparent size of the A and B atoms in this structure. Gel1er" proposed a scheme for reproducing the lattice constants of the phases by the use of a list of effective C.N. 12 radii for the component elements. Reported here is a survey of the A,B combinations which appeared favorable for the stability of the Cr,O-type phase but which, at the time the investigation was begun, either had not been reported upon or had conflicting reports as to the existence of the structure. Seventy systems were investigated, and 8 Cr,,O-type structures were found. Six of these also were reported by other investigators in the interval between the start of this investigation and its completion. This survey yielded information as to the influence of the relative sizes of the A and B atoms on the stability of the phase and, for the various families of Cr,O-type phases, the effects of the sizes of the A and B atoms on the lattice constant. Likewise, a somewhat clearer picture of the connection between the position of the A and B elements in the Periodic Table and their Cr,O-type phase-forming tendencies has become apparent. Experimental Procedure Alloys were prepared in the form of arc-melted 3-gram buttons in all cases where the vapor pressure of neither component was high enough to cause

Jan 1, 1959

By Walter H. Ortel, George B. Wallace

INTRODUCTION A greater understanding is required about the factors which control tunneling operations if we are to meet the expected demand for tunnels. Much of the needed information can best be achieved by the proper use of instrumentation and advanced engineering concepts. Tunnel measurements and their analysis may prove to be the key which will give the insight necessary to understand the relationship of rock, tunnel supports, and linings. There are three main areas which can be improved through the use of tunnel instrumentation. First, and of prime importance, is safety for men and the project. When unstable conditions occur, sets become distorted. Even without measurements, it is sometimes possible to tell when trouble is approaching. In effect, the set acts as a load cell. Distortions in the set indicate reinforcements may be required to maintain stability. Additional sets or rock bolts, if they are placed soon enough, may provide this stability. However, when large rock displacements occur in short periods of time, it could be too late. Figure 1 is an example of the difficulties encountered in stopping moving rock. To stop the movement and possible failure, large props were placed above the spring line and the massive concrete gravity buttress was constructed along the legs. Rock bolts from the buttress deep into the rock were also used in an attempt to stabilize the rock mass. However, this work is for a highway tunnel and eventually these props and buttresses must be removed.

Jan 1, 1971

By J. D. Bateman

At Giant Yellowknife, where high grade gold-bearing orebodies are highly irregular in shape, geology has been applied extensively to the mining of ore. The classical functions of the mine geologist in the fields of exploration and mine development have been extended to guide ore extraction, ensuring "clean" mining and effectively reducing waste dilution. THE property of Giant Yellowknife Gold M.ines Ltd. is situated west of Yellowknife Bay on the north shore of Great Slave Lake, a distance of 600 air miles north of Edmonton, Alberta. The Giant claims were staked in 1935, the company was formed in 1937, and the main orebody system was disclosed by diamond drilling in 1944 following a geological study of the property by A. S. Dadson,* Consulting Geologist for the company. Production began in 1948 at the rate of 200 tons per day and, during 1950, reached a daily rate of 425 tons. During the first 3 years of operation a total of 366,000 tons was milled with an average grade of 0.79 oz of gold per ton. Work is in progress with an expansion to 700 tons per day in view. A descriptive account of the geology and gold-bearing shear zone has appeared previously.* The rock formations in the vicinity of Yellowknife Bay have been subjected to protracted pre-Cambrian tectonic deformation culminating in a series of late faults having a cumulative horizontal displacement exceeding 11 miles. The Giant property is underlain by part of an Archean sequence, several miles thick, consisting of basic volcanic flows and minor intercalated tuffs. The volcanic succession forms the west limb of a major syncline, the flows facing east, but overturned on Giant property to dip west at 65" to 75". Orebodies are confined to shear zones up to 200 ft in width, which were formed along early thrust faults. The shear zones assume fold-like attitudes, the larger of which have an amplitude of several hundred feet. The rock formations beyond the limits of the zone of shearing do not reflect the simulated folds, the axes of which are within a few degrees of the strike of the flows. The schistosity and most of the planar elements in both the shear zones and the orebodies dip west • A. S. Dadson and J. D. Bateman: Structural Geology of Camdian Ore Deposits, Can. Inst. Min. Met. Jubilee Volume (1948), PP 273-283. at angles between 65" and 75", generally corresponding to the dip of the flows. The planar elements within the shear zone system thus dip more or less constantly west whether the shear zone is flat, vertical, or expressed as east or west dipping limbs. The shear zones reflect the deformation and alteration of the basic volcanic flows into chlorite schists which, in most places, have undergone metasomatic replacement to form chlorite-sericite-carbonate schists or sericite schists. The boundaries between the shear zones and country rock, although often gradational, usually can be defined within a few feet or even inches as they are expressed by the limits of metasomatic alteration. Orebodies may occupy a small or large proportion of the shear zone and, although they generally conform to the shape of the zone, their morphology is much more complex. Ore boundaries in some instances are sharp and can be delineated with a chalk line; but more generally, a large proportion of the ore boundaries is not visually obvious and can be determined only by the perception acquired by the geological mapping of ore or study of drill cores. Ore shoots in fold-like attitudes may transect the planar elements of the shear zone at any angle; yet the schistosity within the ore shoot may be coincident with that in the enclosing shear zone. Thus it is clear that problems may arise in the delineation of mining boundaries. Ore generally consists of 20 pct or more quartz with ferruginous carbonates in sericite schist deposited in two dominant stages. The earlier stage limits of quartz with carbonate, pyrite, and very fine-grained arsenopyrite in lenses and bands. The later stage consists of quartz-carbonate lodes, in

Jan 1, 1952

By M. Van Siclen

THE outstanding fact in connection with dust disease in. the United States at present is the growing recognition of its seriousness by state officials and by the more progressive operators of mining, metallurgical and allied industrial plants. The same may perhaps be said of labor in some. of its better organized centers, but the average independent non-. union workman continues, as of yore, to suffer the toll of disability and. even of death from dust inhalation without realization of the source of his ill-being. Progress in the betterment of the handling of sufferers from dust disease and of the conditions creating dust hazards in mining and allied industries is pursuing a course similar to that of the now widespread campaign against accidents, in which the risk is more obvious, more severe, and was naturally recognized sooner. The coming on of dust disease is generally relatively slow and its immediate effects not infre-quently masked by or attributed to other diseases. Marked exceptions to this general rule have occurred in districts where the dust is particularly pernicious, such as the Rand and Joplin; yet such exceptions, unhappy in themselves, opened the eyes of medical men, and of those in other localities charged with the responsibility for the welfare of industry, to the much more widespread if less spectacular hazard existing from the inhalation of. dust in all rock-excavating operations and all industrial operations creating inorganic dust, whether it be crushing and grinding, sand-blast-ing, granite-cutting, or what not. Advancement to date in the United States in prevention and treat-ment has been slow, yet the record shows that quantitative methods for determining the degree of hazard and means for decreasing it were being developed as far back as 25 years ago; and that more rapid progress may be looked for from now on. In 1908, in this country; F. L Hoffman?(1) discussed the mortality from consumption in dusty trades, especially brass foundries; and in 1913.E. R. Hayhurst(2) described the effects of inhalation

Jan 1, 1933

By W. J. C. Venter

The use of activated carbon to improve the selectivity in the separation of base metal minerals from bulk concentrates played an important role in the development of separation techniques employed at Tsumeb Corp.'s Tsumeb and Kombat mines. The Kombat mill fiowsheet and metallurgical data are given with particular reference made to the separation techniques using activated carbon. The mine's historical background, geology, and mining methods are described briefly.

Jan 1, 1974

By John Garcia

IN some districts of the bituminous coal field the problem of construct-ing bulkheads to seal off water under pressure is becoming increasingly important. Recently this matter has been brought very much to the front by the loss of a large Illinois mine due to failure of a bulkhead that separated it from several old, flooded mines. As this great misfortune has provoked much inquiry about proper bulkhead design, it-is felt that a description, of the successful and extensive water-sealing practice at three mines that have different natural conditions will be of considerable interest to those connected with properties having a present or future water problem and to engineers that may have to design safe bulkheads of economical construction. These three mines are the Saxton and Dresser, near Terre Haute, Ind., and the Hegeler, near Danville, Ill. All three have water conditions that make it necessary to regularly seal off all worked-out sections of the mine, and there are considerably over a hundred bulkheads in each. As far as the writers know, these three mines are the only ones in the bitu-minous coal fields of the United States with anything like so large number of water seals and experience, although a number of other mines are known to have a few bulkheads. More detail will be included herein on the Saxton mine than on the others, as the writers are more familiar with it.

Jan 1, 1937

By Clarence Zener

[ ] THE present investigation started in an attempt to understand certain details of the decomposition of austenite, and of the effect of alloying elements thereon. As the investigation proceeded it became apparent that not only these details, but all the general features of austenite decomposition, could be understood in terms of fundamental physical principles. Since the direct applicability of these physical principles has not been previously recognized, it was decided to incorporate the original results of the investigation into a review of the general subject of the kinetics of austenite decomposition. This review constitutes the present article. An extended summary of the results is given on pages 27 to 30. This article, which deals with the kinetics of phase transformations, may appropriately be considered as a sequel to two recent articles1,2 from this laboratory on the equilibrium relations in medium alloy steels.

Jan 1, 1946

By W. H. Emmons

ALTHOUGH gold is one of the rarer metals, it is widely distributed; it is found on all of the continents and in each of the grand metallogenic provinces of the earth. It is prominent particularly in the shield areas of the earth; these areas have produced a large part of the world's lode gold and in most of them gold lodes are more important than the lodes of other metals. The Scandinavian shield is the only one that has not produced much gold. Nearly all of the world's gold has been derived from lodes and from sands and gravels where gold placers formed by the destruction of lodes. The gold derived from magmatic segregations, from pegmatites and from contact metamorphic deposits is quite subordinate to that derived from auriferous lodes. The lodes include all veins and related deposits that are formed by hot waters that move along fissures or other openings and that deposit vein matter in the fissures and by replacement of the country rocks along the fissures. All of the shield areas of the earth are characterized by large areas of granitic rocks including granitic gneisses, granodiorites and other acid intrusives which here are included in the general term "granite." The granites are intruded into schists, ancient lavas and other rocks which here are designated as the "invaded" rocks. The granites are parts of what once were great batholiths: that is, they are the remaining portions of great deep-seated bodies that slope outward, have very irregular roofs and so far as known have no floors but extend downward to great though unknown depths. Some of them are scores or hundreds of miles across and contain islands or "roof pendants" of the invaded rocks at places where the roofs of the batholiths were low-that is, where erosion has not yet completely unroofed the batholiths.

Jan 1, 1932

By John A. E. M. Church

THE prospector's pan was the first implement used for saving gold, and its action is so effective that it has never been equalled for thorough work. Copper plates, blankets, sluices, and amalgamators of several patented designs have thrust it aside, but in spite of all the advances made there is no dispute among experienced men as to the comparative thoroughness of the work done by it and its rivals. When its rivals are doing their best, the pan can take their discarded refuse and prove their inefficiency by producing from it not only gold, but even the mercury which has been lost from the machines themselves. The trouble with the pan has always been that it was only a tool. Man was the machine that moved it. His work was high-priced, the quantity treated small, and it was impossible to use the pan for any but the richest sands. As a consequence the best gold-saving appliance known has been discarded for years and replaced by machines of inferior excellence, but which could more than make up for their limited ability in saving gold by their capacity for treating great quantities of ore. Mr. Peck is one of the old-time amalgamators of the Comstock district, and the first idea of the new machine came to him as he used to pan below the tailrace of his mill. No matter how fine the work of the mill was, the pan invariably proved that better could be done. The tailings always contained gold, silver, and mercury. This state of things is just as true to-day, after all the improvements that have been made, as it was then, and the much-vaunted method of the " Washoe process" consists in extracting 72 per cent. of the gold and silver by one operation, and then repeating this operation half a dozen times to get out about one-third of the remainder. With all the advances of twenty years in milling, there is nothing more crude in metallurgy than the treatment of tailings in many of the large mills of the West.

Jan 1, 1880

By John A. Church

Jan 1, 1880

By R. J. Wagner, Jim Douglas Jr., P. M. Blair

The calculation of the behavior of an oil reservoir during a water flood has long been an important problem to reservoir engineers. Buckley and Leverett derived the differential equation which describes the displacement of oil from a linear porous medium by an immiscible fluid, but this equation could not be solved by the methods of classic mathematics. Consequently, in order to integrate the equation over the length of the reservoir, they neglected the effects of capillary pressure. In the present paper, a numerical method has been developed for determining the behavior of a linear wafer flood with the inclusion of capillary pressure. The differential equation which was derived for the case of incompressible fluids is second order and non-linear. This differential equation was approximated by an implicit form of difference equation which is second order correct in both time and distance. An electronic digital computer was used to perform the numerical solution of the difference equation. INTRODUCTION The problem of calculating the flow and distribution of fluids in an oil reservoir subjected to a water flood has long challenged the reservoir engineer. The ability to solve this problem would provide a valuable tool for the design and study of field waterflooding programs. One of the first contributions in this field was made by Buckley and Leverett,'.' who developed a method of calculating waterflood performance in a linear reservoir. Their technique was limited by the practical necessity of excluding quantitative consideration of capillary pressure. It is the purpose of this paper to describe a method for calculating the behavior of a linear water flood with capillary pressure considered. This method, although limited to the linear case, should serve as a step toward the solution of the two- or three-dimensional waterflooding problem which would better describe actual reservoirs. The treatment of the problem has assumed that the reservoir is linear and homogeneous, that both oil and water -are incompressible, and that gravitational forces may be neglected, and that water is injected into one end of the reservoir and oil and water are produced from the other. Though these assumptions may not be directly applied to natural reservoirs, they are closely approached in many laboratory core tests. The physical problem has been represented mathematically by means of a differential equation and suitable boundary conditions. The inclusion of capillary pressure effects causes the differential equation to be second order and non-linear, and it is not amenable to solution in terms of known functions. Nevertheless, the problem may be solved by numerical methods. The authors have successfully calculated several cases from the start of water injection through to depletion of the hypothetical reservoir using realistic capillary pressure and relative permeability characteristics that were chosen so as to put the method to a test. DIFFERENTIAL EQUATION In two- or three-dimensional problems involving the two-phase flow of incompressible fluids through a porous medium, the equations describing the flow can be combined until only two dependent variables remain, the pressure in one phase, and the saturation of one phase. These variables appear in two simultaneous partial differential equations which are derived on the basis of the conservation of mass and Darcy's law as applied to two-phase flow. For a linear reservoir, this system of differential equations can be reduced to a single, nonlinear, second order, parabolic differential equation for one dependent variable, the saturation of one phase. For incompressible water and oil, it can be shown that the conservation of mass for the two phases requires that Where q, and q, are the water end oil flow rates per unit cross-section, s, and so their saturations, +, the porosity, and [ and T, dimensional space and time variables. Darcy's law, as extended to two-phase flow including the effect of capillary pressure,' is as follows:

By Louis C. Just, Robert L. Sandefur, Carl E. Williams

In 1981 Ertec Rocky Mountain, Inc. completed a significant development in contemporary planning support; MINEPAK was completed, tested on various properties and offered for license. MINEPAK was one of the first computer systems for ore body analysis and mine planning that - Was designed as an interactive and completely integrated system - Was portable so that it can run on many hardware systems - Was really user friendly - Can run on minicomputers and on some microprocessors - Was built around a data base management system MINEPAK was designed to be a completely general block modeller and it achieved that goal. Since it contained a gridded file type, surfaces could be easily modelled but the system needed extensions to allow layered deposits to be modelled with the same ease as block models. So COALPAK was designed. COALPAK is an extension as well as a modification of MINEPAK. A 'layer' file type was defined and retrofitted into the existing system, new software tools were developed for modelling layered deposits, and tools for strip mining were written.

Jan 1, 1983

By R. T. Hukki

This paper presents a preliminary analysis of the fundamental relationship between the net energy used and the respective product size throughout the entire range of sizes covered by crushing and grinding, and an attempt to find a sensible correlation between the existing theories. Walker, Lewis, McAdams, and Gilliland' have given the following differential equation of a general form for comminution: dE = -C§ [1] where E is the net energy required per unit weight in a certain process of comminution; x is the factor indicating the fineness of the product; n is the exponent indicating the order of the process, and C is a constant related with the material, units chosen, etc. H exponent n in the above equation is replaced by numerical figures 2, 1, and 1 1/2, the integrated form of the general equation leads to the well known fundamental theories represented by the law of von Rittinger,' law of Kick, and the third theory of comminution by Bond, respectively. The total net energies (E) from infinite feed size to a product of size x are as follows: The net energy required in a certain process of comminution is proportional to the new surface developed according to the law of von Rittinger, to the weight or size of the bodies treated according to the law of Kick, and to the length of the new cracks formed which initiate breakage according to the theory and explanation by Bond. On a logarithmic paper, where particle size is presented on the abscissa and energy consumption on the ordinate (see Fig. 21, all three relationships are represented by straight lines. The slope m of the line according to the law of von Rittinger is equal to -1.0; of Kick, 0; and of Bond, -0.5. Experimental evidence in favor of the law of Rittinger has been presented, e.g., by Gross and zimmerley5 on quartz crushed in a drop weight crusher and evaluated for surface by the method of dissolution, by Dean on magnetite crushed by a similar method and evaluated for surface by the determination of coersive force, by piret7 and co-workers on a group of minerals crushed again by a similar method as well as by compression and evaluated for surface by permeability and gas adsorption methods, and by schellinger8 on a group of minerals ground in a calorimetric ball mill and evaluated for surface by gas adsorption. Experimental evidence in favor of the law of Kick seems to be scant in the field of comminution. On the other hand, in the field of mechanical engineering Kick's law seems to be of fundamental nature in processes such as cutting, pressing, shaping, and rolling of metallic substances. Experimental evidence in favor of the third theory has been provided by Bond." To a large extent, data are based on the vast amount of grindability tests performed in the laboratories of Allis-Chalmers Manufacturing Co. In addition to the devoted proponents of one or the other of the basic theories listed above, certain investigators have indicated that one of the theories might be applied for a certain range of sizes, while another theory might be used for other sizes. In a discussion of a paper by Bond," Dobie" presented a statement at the International Mineral Dressing Congress in London (1952) indicating that 1) for large particles, the law of Kick was approximately correct; 2) for finer particles, von Rittinger's suggestion was nearer to the truth; and 3) Bond's new

Jan 1, 1961

By Pope Yeatman

THE Committee on the Elimination of Waste in Industry, of the Federated American Engineering Societies, in its report says that "Waste in -industry is attributable to four causes: 1. Low production, caused by faulty management, of materials, plant, equipment, and men; 2. Interrupted production caused by idle materials, idle plants, and idle equipment; 3. Restricted production intentionally caused by ,owners, managers, or labor; 4. Lost production caused by ill-health, physical defects and industrial accidents. The committee sent out elaborate questionnaires, and in them divided the responsibility into Manage-ment, Labor, and Outside Contracts. These question-naires showed that in the different industries examined the responsibility of Management was from 50 to 80 per cent. and of Labor from 9 to 28 per cent. The percentage of responsibility that Management was held accountable for was much larger than any of us supposed. However, when this question is studied, we realize how necessary it is to select, in the first instance, suitable personnel, in the form of directors, managers, heads of departments, experts, etc. We would like to -believe that the percentage of responsibility of Management for waste in the mining business was less than that quoted above, but there are so many mining properties started up and operated by men of no experience in such lines, and there have been so many improvements in late years in mining and metallurgical methods not taken advantage of, that we can not believe that. the percentage will vary much from that already quoted. Quoting from a report approved by the Committee on Management of the American Society of Mechanical Engineers: Management is the art and science of preparing, organizing, and directing human effort applied to control the forces and util-ize the materials of nature for the benefit of man.

Jan 3, 1922