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By William Kent

THE dynamometer herein described is a modification of the one invented by Mr. Samuel Batchelder, of Boston, nearly forty years ago, a description of which may be found in the Journal of the Franklin Institute, 1843, vol. xxxii,.p. 277, and in the Scientific American of August 31st, 1878. The modification consists in providing a method of making an automatic record, and of indicating more minute variations of the power transmitted. The improved dynamometer was designed by the writer in 1877, and was built a few months since by the Class of 1879 of the Stevens Institute of Technology. The accompanying cut, taken from the Annual Announcement of the Stevens Institute, represents the dynamometer without the recording attachment. It consists, as shown, of two stout cast-iron frames, held together by bolts in bearings, in the top of which frames run two shafts, each carrying a pulley at its outer end and a bevel gear-wheel of 45' at its inner end. One of these shafts is the driving-shaft, connected by belt to the engine or other prime mover; the other is the driven shaft, connected by belt to the machine driven. The power is transmitted from one shaft to the other through two other bevel-wheels of 45' gearing with the first, the shaft common to them and on which they run freely being at right angles to the axis of the two shafts first mentioned, and carrying at one extremity a heavy pendulum. The bevel-wheels being connected, as shown, and the power being applied to the driving-wheel, the two intermediate wheels with their common shaft have a tendency to revolve around the driving-axis, which tendency is a measure of the force transmitted, and is resisted by the moment of the weight of the pendulum. In the Batchelder dynamometer the four bevel-wheels and their shafts are used, but

Jan 1, 1880

By William Bent

THE dynamometer herein described is a modification of the one invented by Mr. Samuel Batchelder, of Boston, nearly forty years ago, a description of which may be found in the Journal of the Franklin Institute, 1843, vol. xxxii, p. 277, and in the Scientific American of August 31st, 1878. The modification consists in providing a method of making an automatic record, and of indicating more minute variations of the power transmitted. The improved dynamometer was designed by the writer in 1877, and was built a few months since by the Class of 1879 of the Stevens Institute of Technology. The accompanying cut, taken from the Annual Announcement of the Stevens Institute, represents the dynamometer without the recording attachment. It consists, as shown, of two stout cast-iron frames, held together by bolts in bearings, in the top of which frames run two shafts, each carrying a pulley at its outer end and a bevel gear-wheel of 45° at its inner end. One of these shafts is the driving-shaft, connected by belt to the engine or other prime mover; the other is the driven shaft, connected by belt to the machine driven. The power is transmitted from one shaft to the other through two other bevel-wheels of 45° gearing with the first, the shaft common to them and on which they run freely being at right angles to the axis of the two shafts first mentioned, and carrying at one extremity a heavy pendulum. The bevel-wheels being connected, as shown, and the power being applied to the driving-wheel, the two intermediate wheels with their common shaft have a tendency to revolve around the driving-axis, which tendency is a measure of the force transmitted, and is resisted by the moment of the weight of the pendulum. In the Batchelder dynamometer the four bevel-wheels and their shafts are used, but

Jan 1, 1880

By Percival Roberts

IT may seem necessary to offer an apology for presenting for consideration a process which is conspicuous by its absence in the literature of the Institute, and which may be thought by some to belong to the past in metallurgy, and to have been already superseded. But the large capital invested in puddling calls for a careful consideration of the question whether the time has certainly arrived when the puddling furnace must be replaced by the converter and open-hearth furnace. May there not still be a place for puddled iron alongside of molten iron and steel, and is not the improvement of the puddling process itself worthy the attention of engineers equally with the Bessemer and open-hearth processes? The changes involved in the conversion of pig iron into wrought iron are well understood and need only be briefly alluded to. The patent of Henry Cort bears the date of 1784. Since that time the improvements in the process have mainly consisted in the replacement of sand by iron bottoms by Samuel Baldwyn Rogers in 1818, and the still more recent substitution of iron oxide for the refractory materials used for the rides and bridge of the hearth, which distinguishes the wet or boiling process from the dry or paddling process. Chemically, the process consists in the removal of the metalloids from the pig iron, a result effected mainly by the iron oxide. Silicon is first oxidized, then the phosphorus, and finally the carbon. The silicic and phosphoric acids produced pass into the cinder and the carbonic oxide burns as it escapes from the bath of metal. It is interesting in this connection to note the effect of temperature on the removal of the phosphorus from the iron. As is well known, no phosphorus is eliminated under the oxidizing influences prevailing in the Bessemer converter, while from 70 to 80 per cent. is removed in puddling. But we find, if in working cold short irons

Jan 1, 1880

By J. M. Locke

BRÜCKNER's revolving cylinders for roasting ores, etc., are now used at a number of the mills in Colorado and New Mexico, for the purpose of roasting and chloridizing silver ores, with highly satisfactory results, even from those cylinders of small size, erected before the many improvements of recent date. As examples of the larger improved cylinders, reference can be made to those erected at the Tennessee Reduction Works, Silver City, Grant County, New Mexico, and those which were built, in 1871, at the celebrated Caribou Silver Mill and Mines, Colorado, a mining enterprise which has proved so satisfactory as to have been lately sold to a Holland company for an enormous amount. These cylinders, as now constructed by Messrs. Lane & Bodley, of Cincinnati,, Ohio, are shown in Plate III, in which Fig. 1 is an elevation in perspective, Fig. 2 a longitudinal, and Fig. 3 a trans¬verse section. Fig. 4 is a sketch of a mill, with Brückner's cylinder. The exterior of the cylinder is a shell of boiler iron, 12 feet long by 5 feet 6 inches in diameter. The ends are partially closed with similar material, leaving in the centre a circular opening about 2 feet in diameter, bounded by a flange projecting several inches.. Upon one side is placed an opening closed by a hinged door. Upon the outside of the cylinder are bolted three bands, as shown in Fig. 1, in which the section of the first is square, and that of the third semi¬circular; the second, or middle band, is a strong spur gear. Passing through the cylinder are six pipes parallel to one another, in a plane at an angle of 15° to the axis of the cylinder; these pipes also lie in this plane at an angle of from 30° to 35° to the longitudinal, axis of the plane, as shown in Fig. 2, where the internal arrangement of the cylinder is seen, a perforated diaphragm being formed through part of the cylinder by means of perforated plates placed between

Jan 1, 1874

By J. M. Locke

Bruckner's revolving cylinders for roasting ores, etc., are now used at a number of the mills in Colorado and New Mexico, for the purpose of roasting and chloridizing silver ores, with highly satisfactory results, even from those cylinders of small size, erected before the many improvements of recent date. AS examples of the larger improved cylinders, reference can be made to those erected at the Tennessee Reduction Works, Silver City, Grant County, New Mexico, and those which were built, in 1871, at the celebrated Caribou Silver Mill and Mines, Colorado, a mining enterprise which has proved so satisfactory as to have been lately sold to a Holland company for an enormous amount. These cylinders, as now constructed by Messrs. Lane & Bodley, of Cincinnati,,Ohio, are shown in Plate 111, in which Fig. I is an elevation in perspective, Fig. 2 a longitudinal, and Fig. 3 a transverse section. Fig. 4 is a sketch of a mill, with Bruckner's cylinder. The exterior of the cylinder is a shell of boiler iron, 12 feet long by 5 feet 6 inches in diameter. The ends are partially closed with similar material, leaving in the centre a circular opening about 2 feet in diameter, bounded by a flange projecting several inches. Upon one side is placed an opening closed by a hinged door. Upon the outside of the cylinder are bolted three bands, as shown in Fig. 1, in which the section of the first is square, and that of the third semi- . circular; the second, or middle band, is a strong spur gear. Passing through the cylinder are six pipes parallel to one another, in a plane at an angle of 15" to the axis of the cylinder; these pipes also lie in this plane at an angle of from 30" to 35' to the longitudinal .axis of the plane, as shown in Fig. 2, where the internal arrangement of the cylinder is seen, a perforated diaphragm being formed through part of the cylinder by means of perforated plates placed between

By Henry C. Freeman

During the early period of the construction of the Illinois and Michigan Canal, about 1838, in excavating for the canal, where the present town of Utica stands, hydraulic limestone was discovered, and its value was recognized. A kiln for calcining and a mill for grinding were erected, and the cement was used in the construction of the locks of the canal. This property was subsequently bought by the present owner, Mr. James Clark, and the work has been continued to the present time in much the same primitive manner as it was begun. The bed is exposed in the Illinois River valley by stripping off a few feet of the covering rock. It is from 4 feet to 6 feet 9 inches thick, and nearly level, dipping gently to the northeast. The Utica Cement Company's establishment, which is two miles west of Utica and two miles east of La Salle, was an outgrowth of the Illinois geological survey. The writer was in charge of the district which included La Salle county, and, in working out the details of the geology of that county, discovered, below the Utica bed, another workable hydraulic limestone, which makes its appearance in the northern bluff of the Illinois River valley, rising above the water level at the point where the company's works are established. This cement group, of which there are several thin beds, lies just below the St. Peter's sandstone, with a few feet intermediate of transition-rock, which appears to represent the Calciferous, and is exhibited in place, in concretionary form, at the top of the bluff. The hydraulic beds are very regular, and the one worked by the company is 10 feet thick; or, speaking more definitely, there are two beds, separated by 18 inches of sandstone, lying about two feet above the bottom, and the two beds are worked as one, the sandstone being first cut out and removed, to prevent mixture. In 1869 I was invited to join with a company, and to take charge

Jan 1, 1885

By F. Julius Fohs

As an industry approaches stabilization, greater and greater stress must be laid on its technologic progress, which becomes a prime aid in improving its condition. The oil industry is tending toward this stage and hence its engineers must be pressed into greater service to prevent stabilization and stagnation from becoming synonymous, and to supply, either by improvements in processes or by new machinery, a means of obtaining savings in raw and finished products. Thus profits can be assured warranting continued investment. It may be repeated, technology must apply a slight improvement here, a change there, or a complete renovation, to eliminate inefficiencies and make each dollar invested yield greater results. The profits of ycstcrday were made of rich strikes, of monopolized patents or processes, of control of prices and of markets. Sixty-five years of growth, of large investment, of healthful competition, and of expanding markets, have put the oil industry in the foremost rank of world industries. .Just as the railroads passed a similar period of expansion and growth, and arc being stabilized with reasonable profits, so the oil industry must take advantage of the efforts of its engineers and experts to promote its healthful growth and a better service to the people. Herein is attempted a review of recent progress in which is presented the advances in exploration, production engineering, transportation, refining and greater efficiency in uses of petroleum, with a view not only to stressing important new processes and methods, but also the problems that press for solution. This review can only touch outstanding developments of recent years, but the several Petroleum Division symposiums of our program will present details worthy of attention. Exploration Geology offers directly little new in the technique of oil-finding— major stress being laid on improvement in subsurface correlation by means of foraminifera1 studies, additions to the knowledge of which are being made, slowly but surely, and by means of mineral, and especially heavy mineral, determinations in well samples. The general application

Jan 1, 1927

By H. S. Martin

The Phosphate Recovery Corporation operates three flotation plants, NOS. 1 and 2 concentrators about three miles northeast of Mulberry, Florida, and No. 3 plant at Wales, Tennessee. These plants represent the first commercial phosphate flotation operation and are also believed to be the largest nonmetallic flotation operation in the world at the present time. The details of this paper will be confined to plant No. 2, this being the newest and largest concentrator in Florida, and the flow sheet being practically the same as at plant No. 1. The No. 3 plant has been operated but a short time and has been shut down since December, 1932, on account of the decrease in phosphate rock production. The phosphate washers usually are located centrally on a known deposit so that about two hundred acres of ground can be mined economically to each washer location. The washers are moved to new areas when the distance becomes too great for economical pumping. The flotation plants are built either adjacent to a washer, so that current debris may be utilized, or on the site of a former washer where there is sufficient accumulated debris available for mining, and the flotation plants must also be moved from time to time. Most of the water used in the Florida flotation plants is recovered after passing through a circulating system where most of the fine SUSpended matter is settled out, but some make-up water is obtained from deep wells near the plant. Power is obtained from the Tampa Electric Co. through the distribution facilities of the International Agricultural Corporation. Flotation concentrate is hauled from the plant by trolley over the International Agricultural Corporation's trolley system, to the drying plant at Prairie, one mile northwest of Mulberry. Ore Treated In the pebble phosphate district of Florida, the phosphate mineral, or collophane, is usually found in horizontal beds of varying thickness

Jan 1, 1934

By Henry M. Howe

SECTIONS 1. INTRODUCTION.—In this investigation the meltingpoint and the specific heat of certain artificial silicates were determined by the method of mixtures, using a large platinum-ball pyrometer. The silicates were placed in platinum crucibles on the hearth of a small regenerative gas-furnace (Figs. 1 and 2), and the platinum ball was placed between them. The temperature of the furnace was usually raised very slowly, the behavior of the silicates being observed as they gradually grew hotter; and their temperature was ascertained indirectly from time to time by determining that of the platinum ball, which to that end was temporarily withdrawn from the furnace and immersed in a known weight of water in a calorimeter. The weight and specific heat of water and of platinum ball being known (the specific heat of the latter approximately), it mas possible to calculate the temperature of the platinum ball, which was assumed to have been substantially that of the silicates which surrounded it in the furnace. The specific heat of the silicates also was determined by the method of mixtures. Their temperature having been determined as just described, one of them was dropped into a known weight of water in a calorimeter, whose rise of temperature was then noted. Knowing the weight and initial temperature of the silicate, its specific heat was wily calculated. The reults obtained, especially as regards the melting-point, must be regarded as first approximations. The technical difficulties encountered were so serious as to raise doubts, now from one cause, .now from another, as to the accuracy of most of the results: hence I give but a few, those which were reached without mishap, and with proper observation of the various precautions. The difficulties encountered are referred to again in Section 6. The investigation was carried out in the metallurgical laboratory of the Massachusetts Institute of Technology, and part of. The

Jan 1, 1890

By Ilmar Stöckel, Gösta Harlin, Agne Rustan

INTRODUCTION This chapter is a continuation of the studies by Rustan and Stockel (1979, 1980) on techniques for automating ventilation in Swedish mines and construction works. The studies have been financed by the Swedish Board of Technical Development. As a result of the studies it has been recommended that a good solution to diesel exhaust emission would be automatic, step by step control of the fans near the working place. Diesel vehicles are the major polluters underground in the mines. Therefore, we have suggested that diesel vehicles regulate the fans The goal of the continued study has been to find a way for active diesel vehicles to start and stop gallery fans at both intake and return air. In this paper different methods for activating fans are discussed. The best methods are chosen and tested in the mine. In this study we have found that change of temperature is an inexpensive and effective way to start and stop crosscut fans in sublevel caving and radio signals seem to be an attractive system for starting and stopping gallery fans . This work has been done in close collaboration between LKAB in Kiruna and the University of Luleå, Divisions of Electronics and of Mining and Rock Excavation. An advisory group for the project has been established with ventilation experts from the mines, representatives of the local mine workers' unions, and authorities from the local offices of Governmental Inspection of the Workers Safety. VENTILATION SYSTEM STUDIED In the project the ventilation system at LKAB in Kiruna was studied. The mining method used is sublevel caving with 9-13 m slice height. The air above ground is heated in winter by hot water and the main fans push the air down to a main distribution level along the 4000 m long and about 100 m wide ore body. From the distribution level, air is taken through shafts down to the sublevels, where it is pushed through the levels by local gallery fans on both the intake and return sides, Fig. 1.

Jan 1, 1981

By Robert P. Roberts

In order to obtain data on the thermal effect of the blast-furnace jacket and on the water consumption in these jackets a series of tests were run on the 56 by 180 in. blast furnaces at the Great Falls Reduction Department of the Anaconda Copper Mining Co., at Great Falls, Mont. The arrangement of the jacket is shown in the transverse section of one of the furnaces (Fig. 1) on which the tests were made. The nose, spout, and breast jackets have independent water supplies and discharges. The end and side jackets are connected in pairs, as regards water supply, the feed water entering at the bottom of the lower jacket and overflowing into the bottom of the jacket immediately above it, and discharging into an independent overflow pipe for each pair of jackets. Tests were run on the main side and end jackets, the breast jacket, the spout, and the nose. Measurements were taken of the quantity of water discharged per minute and the rise in temperature of the water in its passage through the jacket. The product of these two results, expressed in the proper units, evidently gives the number of units of heat removed per minute by the water. Sufficient work was done on each type of jacket to determine its behavior under different conditions, and the results from each set of conditions were checked by repeating the work from three to six times. The method used was as follows: The overflow from the jacket to be tested was arranged to discharge at will into a barrel, mounted upon platform scales. The discharge temperature was read just before turning the water into the barrel, and just before turning it back to the sluice; if the test lasted more than a minute, additional temperature readings were taken at 1-min. intervals from start to finish. The elapsed time of running the water into the barrel was determined with a stop-watch, and this figure, combined with the in-

Jan 1, 1914

By Arnold Hague

At the Buffalo meeting, October, 1888, Dr. Raymond presented a paper entitled: "Soaping Geysers" (p. 449 of the present volume), in which he called attention to the use of soap by tourists to cause eruptions of several of the well-known geysers in the Yellowstone Park. Incorporated in this paper appears a communication received from me, written from camp in the Park, in reply to some inquiries on the subject. The letter discussed somewhat briefly the means employed by visitors to the Park to hasten the eruptions from hot springs and reservoirs of hot water, which remain dormant for days, or even weeks or months, at a temperature near the boiling-point, without any display of geyser-action. As the paper has called forth considerable comment, I desire to elucidate one or two points in relation to the temperature of the springs, and to answer some inquiries about the composition of the thermal waters. In the summer of 1885, a Chinaman, employed as a laundryman for the accommodation of the tourists at the Upper Geyser Basin, accidently discovered, much to bis amazement, that soap thrown into the spring from which he was accustomed to draw his supply of water produced an eruption in every way similar to the actual workings of a geyser. Tourists with limited time at their command, who had travelled thousands of miles to look upon the wonders of the Yellowstone, soon fell into the way of coaxing the laundryman's spring into action, to partly compensate them for their sore disappointment in witnessing only the periodical eruptions of Old Faithful. Successful attempts upon this spring soon led to various endeavors to accelerate action in the dormant and more famous geysers. In a short time, so popular became the desire to stimulate geysers in this way, that the Park authorities were compelled to enforce rigidly the rule against throwing objects of any kind into the springs. In connection with a thorough investigation of the thermal waters of the Yellowstone Park and the phenomena of the geysers, I undertook a number of experiments to ascertain the action of soap upon the waters and to determine, if possible, those physical conditions of various pools and reservoirs which permitted the hastening of an

Jan 1, 1889

By Henry Hibbard

AT THE beginning of a Henry M. Howe lecture it seems fitting to refer to Howe's great contributions to steel metallurgy, and particularly to the literature thereof. Most of my predecessors in this role have been able, from their association with him, to give direct testimony as to his great services; but although connected with him for years in a business way, I am less familiar with what might be called his academic side, except as .it is embodied in his utterances, written and oral. Howe was adept in his genial way in extracting information in any line which, at the time, was of interest to him. In a technical lecture one expects as a rule new knowledge-something about recent advances relating to the subject. On this occasion, however, I will ask you to go back with me to the primary department of steel lore, as the title of my lecture shows, to review the more fundamental features in that field for the purpose of seeking some gaps which we can fill and so give the subject renewed interest. In thus going back one must inevitably repeat many familiar facts, but that seems to be necessary in order to reach a clear understanding of the unrecorded matters. The full interpretation of a steel analysis is at present unattainable, though much progress toward that end has been made. The ultimate analysis, giving the percentages of the five commonly determined elements, does indeed usually give a fair idea of what the steel is, and is ordinarily enough, with knowledge of its history and physical condition, to enable it to be assigned to some purpose or use for which it is reasonably suitable. But discrepancies arise. Every maker and every user of steel knows, from at least occasional examples in his own experience, that the ultimate analysis is insufficient by itself to enable one to tell positively, from its interpretation, either the mechanical properties of the steel or its adaptability to the purpose for which it was made. Further, if, while having the specified composition, it is abnormal or unsatisfactory, why it is so. Good, bad and indifferent steels may have substantially the same ultimate analysis.

Jan 1, 1928

By Henry D. Hibbard

At the beginning of a Henry M. Howe lecture it seems fitting to refer to Howe's great contributions to steel metallurgy, and particularly to the literature thereof. Most of my predecessors in this role have been able, from their association with him, to give direct testimony as to his great services; but although connected with him for years in a business way, I am less familiar with what might be called his academic side, except as it is embodied in his utterances, written and oral. Howe was adept in his genial way in extracting information in any line which, at the time, was of interest to him. In a technical lecture one expects as a rule new knowledge—something about recent advances relating to the subject. On this occasion, however, I will ask you to go back with me to the primary department of steel lore, as the title of my lecture shows, to review the more fundamental features in that field for the purpose of seeking some gaps which we can fill and so give the subject renewed interest. In thus going back one must inevitably repeat many familiar facts, but that seems to be necessary in order to reach a clear understanding of the unrecorded matters. The full interpretation of a steel analysis is at present unattainable, though much progress toward that end has been made. The ultimate analysis, giving the percentages of the five commonly determined elements, does indeed usually give a fair idea of what the steel is, and is ordinarily enough, with knowledge of its history and physical condition, to enable it to be assigned to some purpose or use for which it is reasonably suitable. But discrepancies arise. Every maker and every user of steel knows, from at least occasional examples in his own experience, that the ultimate analysis is insufficient by itself to enable one to tell positively, from its interpretation, either the mechanical properties of the steel or its adaptability to the purpose for which it was made. Further, if, while having the specified composition, it is abnormal or unsatisfactory, why it is so. Good, bad and indifferent steels may have substantially the same ultimate analysis.

By Frank Firmstone

In April, 1873, No. 2 furnace at the Glendon Iron Works being out of blast, it was decided to alter it from an open to a closed top. The three side flues, through which a part of the gas was formerly taken off, were 15 feet below the top, and as, for various reasons, it was not convenient to cut new flues through the brickwork at the top, as is commonly done with closed-top furnaces, a modification of Coingt's charger was employed. This apparatus, as figured by De Vathaire,* consists of a cup or hopper, like that used with the cup and cone, and a central pipe for taking off the gas, which descends some distance into the furnace, and has a projection around it forming a seat for a ring of a triangular cross-section, which closes the opening between the cup and the central gas-pipe. The charge is put into the cup, and by lowering the ring, is thrown into the furnace, a part going outside of the ring toward the walls, and a part through the inside toward the gas-pipe. In this form the apparatus was not applicable, for: 1st. With a gas-pipe three feet in diameter, in a top eight feet in diameter, the openings left by lowering the ring would not be large enough to let lump coal pass through. 2d. For the charger to shut tight, the ring must bear equally against the projection made for it on the gas-pipe, and against the edge of the cup. This would not be difficult to effect when the apparatus is first put up, but a comparatively small change in the relative position of the parts, such as is almost certain to occur from expansion, would cause the ring to touch the pipe or the cup, whichever happened to be the lower, first, and leave a leak between it (the ring) and the other. In the plan adopted (Figs. 5 and 6, Plate I), the central opening in the ring is closed by the bottom of the gas-pipe, whereby more room is left for the passage of the stock when the charger is open, than if the pipe descended into the furnace; and the pipe, instead of being rigidly supported, rests on the ring, when the charger is closed, and follows it for two or three inches as it opens, until stopped by the counter-balance lever C. When the ring is raised to close the furnace top, it comes in contact first with the bottom edge of the gas-pipe, then both are raised together, until stopped by the ring touching the edge of the cup. In this way a good joint is made at both places.

By Joseph S. Young

During 1975, the Reclasource Corp. constructed and started up a plant for the recovery of mill scale, coke breeze, blast furnace dust; blast furnace sludge; and TOC dust, at the site of Crucible Steel, Inc., Midland, Pa. The Reclaform Process was employed as the criteria for plant design. This process takes the solid wastes (as listed above) which are commonly found in integrated steel mills, sizes them, forms them through the use of a carbonaceous binder briquetting system, and fixes the binder through a final heat treating step. Blast furnace tests have been performed on 15,000 tons of Reclaform briquets. This paper gives a brief history of the program, and describes the process and the raw materials involved. The blast furnace campaign and its major conclusions are discussed.

Jan 1, 1977

By W. Mostowitsch, H. O. Hofman

In our investigation of the Behavior of Calcium Sulphate at Elevated Temperatures with Some Fluxes,' we incidentally studied the decomposition of ferric oxide when heated in a current of dry air. We found that at 1,500° C., with 15-min. periods of heating, Fe²,O³, hardly changed in weight, the greatest loss being 0.23 per cent., and we therefore concluded that the compound remained unchanged at 1,500° C. in a current of dry air. In a more recent experiment we heated Fe²,O³, in a current of dry air and found that there was a decided loss in weight. A new investigation upon the behavior of Fe², O³, using a larger amount of substance and heating for a longer period of time, revealed the fact that a measurable dissocia-

Jan 1, 1910

By A. M. Mirani

The Mine Planning System consists of two parts: 1. A Sales Forecast (Sales Planning) 2. A Production Planning. The mathematical methods of the sales forecast are the exponential smoothing and a method with Markov-Chains. By these methods the quantity of material (ore, coal) will be calculated for the time planned. These quantities constitute the points in the production-planning. In the production-planning , special kinds of networks are used for calculating the resources-equipment required, labor and costs. A special routine optimizes the sequence of the mining areas within the mine on the basis of the lowest costs. The resources can be limited. The activities will be shifted when the demand exceeds this limit. The basis of the production-planning are computer files, in which the geological data and economical evaluations are stored.

Jan 1, 1969

By Rudolf Kudlich

The problem of eliminating the hazards of hoisting in mines has been with us since the industry passed its earliest stages, when coal and ore could be won from surface working and tunnels. At first, safety devices were introduced as means of decreasing the amount of labor necessary to produce the mineral, or to increase the amount that could be obtained from a certain opening. For example, crude ladders replaced winding footpaths or steps cut into the walls of the pit or shaft, decreasing the distance it was necessary to carry the product to the surface and eliminating, to some extent, the hazard introduced by the precarious footing afforded by such paths and steps. Latcr, instead of being carried from the pit on the backs of men, the product was hoisted in buckets or baskets on a rope passing over a pulley or around a windlass. Thus the capacity of the pit was considerably increased, and the hazard due to making many trips up and down the shaft was eliminated. From such beginnings accident prevention in mine hoisting advanced with the importance of the industry, until at present hoisting compares favorably with other branches of the mining industry with reference to safe practices. As in the other branches, this progress has been accomplished along two general lines—by legislation, rules, and education, and by the installation of safety devices. Though due credit must be given the former, it is not so satisfactory as the latter. Legislation, to be effective, requires a policing and inspection system to guarantee enforcement, such as we cannot hope to inaugurate. Rules may be satisfactory so long as the employer controls the labor market, and dismissal or some other form of discipline is an effective means of insuring obedience to the rules; but where labor demand is in excess of the supply, or where labor organizations are in control, such measures are not effective. An educational campaign will draw attention to hazards and may awaken a desire to avoid accidents by exercising the proper care. It is necessary, therefore, to place our reliance mainly on mechanical devices to prevent accidents, and to depend as little as possible on laws,

Jan 1, 1923

By Rudolf Kudlich

The problem of eliminating the hazards of hoisting in mines has been with us since the industry passed its earliest stages, when coal and ore could be won from surface working and tunnels. At first, safety devices were introduced as means of decreasing the amount of labor necessary to produce the mineral, or to increase the amount that could be obtained from a certain opening. For example, crude ladders replaced winding footpaths or steps cut into the walls of the pit or shaft, decreasing the distance it was necessary to carry the product to the surface and eliminating, to some extent, the hazard introduced by the precarious footing afforded by such paths and steps. Latcr, instead of being carried from the pit on the backs of men, the product was hoisted in buckets or baskets on a rope passing over a pulley or around a windlass. Thus the capacity of the pit was considerably increased, and the hazard due to making many trips up and down the shaft was eliminated. From such beginnings accident prevention in mine hoisting advanced with the importance of the industry, until at present hoisting compares favorably with other branches of the mining industry with reference to safe practices. As in the other branches, this progress has been accomplished along two general lines—by legislation, rules, and education, and by the installation of safety devices. Though due credit must be given the former, it is not so satisfactory as the latter. Legislation, to be effective, requires a policing and inspection system to guarantee enforcement, such as we cannot hope to inaugurate. Rules may be satisfactory so long as the employer controls the labor market, and dismissal or some other form of discipline is an effective means of insuring obedience to the rules; but where labor demand is in excess of the supply, or where labor organizations are in control, such measures are not effective. An educational campaign will draw attention to hazards and may awaken a desire to avoid accidents by exercising the proper care. It is necessary, therefore, to place our reliance mainly on mechanical devices to prevent accidents, and to depend as little as possible on laws,

Jan 1, 1923