Search Documents

By Mario L. Villa

Another increase in production and the discovery of new pools arc the outstanding developments of the year 1937. Production in 1937 totaled 16,354,706 bbl., compared to 15,457,953 bbl. in the previous year, an increase of 5.8 per cent, of which 5 per cent was due to the Yacimientos Petroliferos Fiscales (Argentine Governnlent Oil Fields) and 0.8 per cent t,o private companies. Table I shows that the most important gain in output was obtained in zone B of Comodoro Rivadavia, partly offset by a 5.7 per cent decrease in the Neuqu6n district. The fields of Salta and Mendoza show an increase of 4.4 and 39.1 per cent, respectively. The determination of bottom-hole pressures was started by Yaci-mientos Petroliferos Fiscales (Y.Y.F.) in Comodoro Rivadavia and

Jan 1, 1938

By G. A. Merkt

THE Isley furnace control, here presented as a novelty in furnace construction, is, in principle, one of the oldest methods of maintaining furnace heat for industrial purposes. Records unearthed in Egyptian tombs and the primitive methods of melting metal practiced by African tribes today indicate that fanning the fire and forcing the furnace by bellows have been an effective means of regulating heat for man's work during thousands of years. Even today, these cruder forms of mechanical draft production are still nn use within the borders of this most highly developed industrial land. Stacks, as we know them, are of com- paratively recent historical age but their attractive simplicity and seeming effectiveness have made them exceedingly popular. And so we find one of the most important types of furnace the world has even known, the open-hearth furnace, duly and more or less properly equipped with a chimney. The regenerative, or reversing, type of furnace, how-ever, required another mechanism between its hearth and the stack to provide a means for alternately con-necting one side and the other of its system of regen-erative chambers and flues to the stack and to a source of fuel and air supply respectively. Various types of reversing valves were developed, some of which are re-markably well designed for maximum efficiency and ease of installation as well as operation. However, this combination has a number of inherent faults which are so difficult to correct as to make efforts in the direction of improving over-all efficiency almost futile. These inherent difficulties are as follows: (1) The necessarily high temperature at which the gases must be delivered to the stack in order to make it operative. (2) The great temperature difference incidental to the reversal of flue gas and air and consequently the large variation in preheated air and fuel delivered to the furnace dur-ing the cycle. (3) The leakages and resistances created by the reversing apparatus and the complicated flues necessary. (4) The inadequate range of control af-forded by the natural draft system, especially under adverse atmospheric conditions.

Jan 12, 1927

By Thomas Read

IN speaking of immaterial problems of industry I am using the word immaterial in its original sense, not consisting of matter; not in its derived sense, unimportant. There is nothing of a paradox in saying that immaterial problems are the most important in human life, for His a matter of everyday observation that much of the news in the daily papers, and most of the world's best literature and drama, deal with human conduct that has for its motive forces that are but little concerned with material things. The engineer's preoccupation with physical forces, in extending his control over them, has not blinded him to the impor-tance of forces that, for want of a better word, I call immaterial; but he has considered that dealing with the one is his job and the other is not. All the evidence of the past decade indicates that the latter are so in-extricably interwoven with the former in modern in-dustrial life that the engineer will have to concern himself with them whether he wants to or not. Some of the most important of the problems arising from the action of these forces relate to the mental hygiene of the workers in industry. Mental hygiene in industry was concisely defined, in terms of the best present knowledge, by Dr. C. Macfie Campbell, speaking last April before the executive com-mittee of the Associated Industries of Massachusetts, and as his statement can scarcely be bettered, I quote it below: "The term mental hygiene is apt to appear vague. The actual stuff with which mental hygiene deals may be briefly reviewed.

Jan 9, 1927

University of Alabama University, Alabama Mining and Metallurgical Society STEPHEN STILLWELL, President VINCENT ZENOBILE, Secretary GEORGE '1 BATOR, Faculty' Sponsor RAY L. FARABEE, Counselor University of Arizona Tucson, Arizona Miners' Society RICHARD BRITTAIN, President FRED W. SHERMAN, JR., Secretary J. B. CUNNINGHAM, Faculty Sponsor E. P. GARDNER, Counselor

Jan 1, 1943

By Phillip Crowson

INTRODUCTION This discusses some of the economic risks and uncertainties which face any company investing in new mineral ventures. These differ mainly in degree rather than kind from other large capital intensive projects, except that economic risks are compounded with technical risks. Mines face a wide variety of physical risks, and in addition the ore reserves may not prove as ample, nor as amenable to treatment as the feasibility studies indicate. On the economic front, mineral projects are subject to risks of fluctuating prices and sales volumes, no matter where they are located, or how they are financed. Typically, they are heavy users of capital compared with their owners' internally generated funds. Long term debt of various types is still the favoured form of finance. A project's currencies and cost often differ from each other and from those of the parent company. Facing up to the various risks associated with fluctuating and uncertain revenues, interest rates and exchange rates are amongst the hardest tasks for natural resource companies. ATTITUDES TO THE MINING INDUSTRY Some have questioned whether the game itself is now worth playing. They have argued that the mining industry's mediocre rewards in the past decade have been insufficient, compared with the risks involved. They can see no prospect of dramatic improvement in the next decade. Demand is highly cyclical and tends to grow less rapidly than economic activity, as a whole. Barriers to entry are low in most mineral markets, but impediments to exit can be substantial. Exit is especially problematic in those minerals where there are large state shareholdings and/or where less developed countries are major producers. The consequence is claimed to be an endemic tendency to excess capacity, and prices barely adequate to cover marginal cash costs. Many of the petroleum companies that moved into mining with such high expectations in the late 1970s have retreated, often bearing the scars of heavy losses. Individual shareholders, taken collectively, place low valuations on their investments in mining companies. The price/earnings ratios of the major mineral producing companies are low compared with their historical averages and with those of other industries. PRICE: EARNINGS RATIOS (October 1988) [UK Industrials 12.0 RTZ 8.4 Cons Gold 12.2 US Industrials 13 - 13.4 Alcan Alcoa Amax Asarco Cyprus Minerals Freeport Copper Inco Inspiration Magma Copper Newmont Mining Nord Resources Phelps Dodge Reynolds Metal Canada TSE 300 10.6 Cominco 8.7 Falconbridge 5.3 Noranda 7.0 Rio Algom 7.2 Teck Corporation 17.] NOTE: Mining companies' p/e based on prospective 1988 earnings, from Kleinwort Benson Securities' weekly Mining World, October 1988. Until 1987, it was argued that share prices correctly reflected the companies' poor earnings potential. Subsequently, the argument has been that earnings have been unnaturally boosted by cyclically high metal prices. The stock market valuations, therefore, correctly reflect future earnings, or at least expected earnings. This seems to be a case of Heads, I win; Tails, you lose. The underlying analysis of metal markets appears

Jan 1, 1990

By T. P. Meloy

In a recent paper, Gaudin and Meloy1 derived a size distribution function for single, impact fracture. Mular2 extended the use of this size distribution to describe the output of carefully controlled grinding experiments. As it stands, the function is difficult to compute. Consequently, a series of tables of the function are presented below: where M(x) is the cumulative fraction finer than size x when x is particle size. Weight percents are tabulated for the single parameter, r, in three different size ranges: from 0 to 1, from 1 to 10 and from 10 to 100. Tables I, II and III are cumulative percent finer and Tables IV, V and VI are for weight percent passing screen size x, retained on the screen below. A number of conditions from the table are plotted in Figs. 1 and 2. Fig. 1 is a plot of the cumulative percent finer vs. size, and Fig. 2 is the weight per-

Jan 1, 1963

By J. J. Sense

This paper deals with the Asarco method for the determination of equipment availability. It is apparent that no single availability equation will provide all of the information necessary for the complete record of equipment availability. In the Asarco system, three separate availability records are carried on major equipment. The first is mechanical availability, the second is operational availability, and the third is a historical record of equipment use. The derivation of the three items and the definitions of the time elements used in the various availability equations are presented and discussed. The Mission unit of American Smelting and Refining Co. is located in Pima County, Ariz., approximately twenty miles southwest of Tucson. The unit consists of an open pit copper mine and concentrator. The concentrate is shipped by rail to company smelters at Hayden, Ariz., or El Paso, Tex. Mine stripping began at Mission in the fall of 1959, and construction of the 15,000 tpd concentrator was started in the spring of 1960. The first ore was treated in midsummer of 1961 and full ore production was reached in August 1961. At that time over 46 million tons of material had been moved from the pit. Current production (ore and waste) averages over 100,000 tpd. Total production to date (ore and waste) is over 120 million tons. Major equipment currently in operation at the Mission pit is as follows: 3 P & H 1800 Electric Shovels - 9 cu yd dippers 1 P & H 1900 Electric Shovel - 9 cu yd dipper 2 B.E. 190-B Electric Shovels - 9 cu yd dippers 35 Euclid LLD Trucks - 60-ton capacity 6 KW-Dart 55-T Trucks - 55-ton capacity 1 KW-Dart D-2550 Truck - 65-ton capacity 1 LeTourneau Westinghouse 65 Haulpak - 65-ton capacity 3 Euclid S-18 Scrapers - 274011 capacity 4 Caterpillar D-8 Dozers 4 LeTourneau Westinghouse Tournadozers 1 Michigan 280 Dozer 2 Caterpillar Model 12 Motor Graders

Jan 1, 1964

By G. C. Wallick, W. R. Foster, J. G. Savins

The theory of the differentiation method for the Couette flow experiment is reviewed. Particular attention is given to the requirements on data analyses in the case of the class of non-Newtonian materials described as viscoplastics, i.e., materials characterized by a yield point or yield stress. Here changes in boundary conditions arise when the shearing stress attains a critical value with the result that the form of the basic integral equation for Couette flow is determined by the flow conditions existing during the measurement. INTRODUCTION In the preceding papers in this series,l,2 the salient features of the differentiation method of rheological analysis in Poiseuille-type flow were discussed. It was shown that a dual differentiation-integration method analysis of the Poiseuille flow of idealized generalized Newtonian and visco-plastic models could be used to develop a spectrum of highly sensitive response patterns in terms of certain characteristic derivative functions. These functions were shown to optimize the selection of the most appropriate functional relationship between f(p) and p from the Poiseuille flow experiment. The present paper reviews the theory of the differentiation method as applied to the equally important Couette flow experiment. We will also discuss the range of variables over which the basic integral equation for Couette flow is applicable when the non-Newtonian material is of the viscoplastic type, i.e., characterized by a yield point or yield stress. THEORY Having described the application of the differentiation method to Poiseuille-type flow in the preceding papers, we now proceed to the case where the test liquid is confined to the annular space between coaxial cylinders of length L, one of which is in motion, i.e., Couette flow, formulating the basic integral equation after the method of Mooney.3 The observed kinematical and dynamical quantities are the angular velocity O and the torque T. Here, the one nonvanishing component of the shear-rate tensor is

By Leo J. Miller

It is both an honor and a pleasure for me to be the keynote speaker for the Paul F. Kerr's Symposium on Applied Mineralogy. Professor Kerr was a man for all seasons to his students, and he treated all students as distinct individuals. Philip Bethke in his memorial to Dr. Kerr summed up our remembrance best by stating that "We have lost our most successful educator-administrator-scholar, who was our steadfast teacher-counselor-mentor-friend." His unique trait was the ability to bring out the best in a variety of individuals In order that their performance was at the peak of quality.

Jan 1, 1985

By Arthur A. Center

HIGH GRADE zinc stocks were reported short early in 1943, but not Prime Western. Maximum production of High Grade was expected to be reached before the middle of the year, and demands of new brass mills were to take all of the increase. In February three premiums (A, B, C) of 2 3/4c. per lb. of zinc in ore were announced to encourage production from high-cost mines, the number of premiums being in proportion to estimates of ore-production costs.

Jan 1, 1944

By Edward C. Mack, Ronald G. Stovash

INTRODUCTION Ronald G. Stovash General Superintendent Consolidation Coal Company Shoemaker Mine Moundsville, West Virginia Consolidation Coal Company's Shoemaker Mine is located in West Virginia's Northern panhandle near Wheeling, adjacent to the Ohio River. Steam coal is mined from the Pittsburgh #8 seam which averages 65 in. in thickness. The 10 in. of draw rock directly above the coal is taken on advancement, but remains when longwalled. The top consists of up to 12 in. of lower quality coal, and immediately over that, up to 10 ft of multi layered shales, coal, and bone. The cover ranges from 300 to 800 ft of shales and limestone. Two longwalls operate in the mine. The first longwall started in April 1975 and is retreating its eighth panel. This wall was the first to use shield supports in the United States. The second longwall started in September 1979 and is currently retreating its first 7,000 ft panel.

Jan 1, 1981

By Goldye Leeds, Marian Balicki

A SURVEY of literature reveals the scarcity of experimental evidence relating to work hardening and reannealing of silver.'-'" With the exception of the well-known X-ray investigation of silver and other metals by W. A. Wood? the effect of progressive cold working has not been studied. The determination of thermal stability of silver in the work-hardened state by means of isochronal or isothermal annealing has been confined apparently to very high reductions only. In the survey made, no study was encountered which endeavored to produce a complete picture of the changes in various properties due to cold working and subsequent reannealing. To fill these gaps and to assemble data that could be used for the determination of activation energies and of frequency coefficients of primary recrystallization, a systematic experimental approach, which was developed by one of the authors, has been applied to pure silver. Material and Processing The silver used was Handy and Harman fine silver, with a spectroscopic analysis at the testing stage of Cu, 0.0001 to 0.001 pct; Te, 0.0001; Pb, Si, Ca, Mg, and Mn, traces. The material was supplied in the form of a rod 0.406 in. diam and was converted into test samples according to the procedure condensed in Table I. It should be mentioned that air annealing was adopted to simulate industrial practice, though it was realized that annealing in a neutral gas or in a vacuum would be preferred. The usual precautions have been taken to eliminate any structural changes and property changes resulting from the storage of the samples prior to annealing or testing. Thus the wires were kept at the fully annealed stage, and the final wire drawing, which produced the desired degree of work hardening, was done just prior to the final annealing or testing. During the short waiting period, the samples were kept in a thermosflask filled with ice. Even with these precautions some strain-age-hardening or self-annealing could occur. To test such a possibility, wires of different reductions were prepared in the manner adopted and portions of them were immediately tested. The remaining portions were similiarly tested after different periods of storage, both at room and melting-ice temperature. Within experimental error, all samples obtained from a wire of a given percentage of reduction yielded identical values. This result qualified the material for further tests and interpretations, because it showed that either strain-age-hardening and self-annealing were absent, or that these effects fully balanced each other. The final annealing was carried out in an electric resistance furnace automatically controlled to within a 10°F. It was realized that the temperature fluctuations were greater than desired for this type of work. TO diminish the errors due to fluctuations of temperature, the hot junction of the thermocouple was placed as close to the samples as possible; the time of soaking was reduced to 15 min; and the number of samples annealed at different temperatures was increased. It will be seen from Table I that some tests were performed on the same material at rising temperature. These will be discussed elsewhere. Room temperature testing was limited to the determination of some of the mechanical properties that are known to be additive in a degree sufficient to be used for indirect study of the kinetics of the reannealing process, Tensile tests, carried out on a manually operated J. Camillon machine, accurate to within permitted the determination of the ultimate stress (U.S.1 and of the 2 in. elongation, (A,). The proof stress (d,e) has been determined from a series of bend tests carried out on a Tinius Olsen Stiffness Tester by using the offset method. This involved accurate determination for each sample of load-angular deflection curves, finding a

Jan 1, 1952

By Walter Weeks

THERE is very little useful material in the litera-ture on the construction of manometers, so each experimenter must devise his own instrument. I have experimented for a number of years and have finally built one that is satisfactory. If we are to obtain accurate friction factors in mine-ventilation problems we must use accurate instruments. The most simple and convenient instrument for the mea-surement of small pressures is the inclined manometer or U-tube. By changing the angle at which the tube is set, any desired magnification of the pressure reading may be obtained. The first question in regard to the manometer is: What liquid shall be used? Alcohol, in my opinion, is the best. It does not cling to the glass and it does not attack the rubber tubes. The next problem is the setting of the instrument at the proper angle. One method is illustrated in Fig. 1. The base plate AC is made horizontal by a level bubble. The plate AB, which carries the U-tube, is hinged at A. The angle z which AB makes with the horizontal may be made any value by pinning the end B at the calculated position on the arm CD. Such an instrument may be designed to read directly in inches of water if a liquid of constant specific gravity is used. If the specific gravity varies, a calculation is necessary to convert the reading into inches of water.

Jan 1, 1923

By J. Kostuik, M. J. de Bastiani

Located in the Elliot Lake mining district of Canada, the Denison mine lies between Sudbury to the east and Sault Ste. Marie to the west. This area is overlain by Huronian sediments filling a basin in the Keewatin basement complex. Subsequent folding of these sediments developed a synclinal structure, known locally as the Quirke Lake Trough, which forms the northern portion of the now famous big Z structure, the geological trademark of this region. Plunging to the west and extending nine miles from the granite outcropping in the north to the Keewatin lava contact to the south, the syncline has dips of 10° to 45° on the north limb and 10° to 20° on the south limb.

Jan 12, 1960

By E. J. Dulis, G. V. Smith

AS reported several years ago,' nitrogen may be taken up from the atmosphere by austenitic Cr-Ni steels during creep or creep-rupture tests. This was indicated by chemical analysis and by the appearance of a new microstructural phase, or phases, tentatively identified as chromium nitride (S), at the surface or at the intergranular cracks associated with fracture. The nitrogen pickup was observed to be dependent on time, temperature, and deformation. In a more recent investigation, a sample was obtained in which there was sufficient of the precipitate to suggest that it could be readily identified by X-ray diffraction. This sample had been taken from a 1/4 in. diam creep-rupture specimen of annealed, type 304L stainless steel of the following initial composition: C, 0.03 pct; Mn, 0.65; P, 0.010; S, 0.019; Si, 0.54; Cr, 19.50; Ni, 12.02; N, 0.031; and Al, 0.005. The specimen had ruptured after 10,470 hr at 1500°F (2000 psi). In this case nitrides were distributed across the whole section of the sample, Fig. 1. The precipitate occurred both at the grain boundaries and within the grains; the latter precipitate had in some cases the appearance of pearl-ite, and in others was distinctly Widmanstatten. Chemical analysis of the sample after test showed 0.64 pct "soluble" nitrogen (soluble in 1:1 hydrochloric acid: water) and 0.18 pct "insoluble7' nitrogen (insoluble in the hydrochloric acid solution but dissolved by fuming sulphuric acid). For identification of the precipitate by X-ray diffraction, the matrix in the surface layer of the specimen was dissolved by prolonged attack in an alcoholic solution of picric and hydrochloric acids. The appearance of the specimen surface after such etching is shown in Fig. 1c. The diffraction pattern of the surface-concentrated precipitate was obtained with a recording spectrometer in both the forward and back-reflection regions (the latter by adapting a special fixture to the conventional X-ray unit). The observed X-ray diffraction lines, Table I, show the presence of Cr,N and CrN; the agreement with interplanar spacings calculated from reported data2,3 is quite good. Since it has been suggested' that CrN dissolves only in concentrated sulphuric acid, whereas Cr2N dissolves in dilute hydrochloric or sulphuric acids, an effort was made to distinguish between the two nitrides. This proved possible, inasmuch as etching in a dilute solution of hydrochloric acid gave a sample in which microscopic examination showed that much of the Widmanstatten-pearlitic precipitate within the grains had been eaten out, leaving the grain boundary precipitate in relief, and which, when examined by X-ray diffrac-

Jan 1, 1953

By Thomas L. Watson

A part of the field-seasons of 1900, 1901 and 1902 mas devoted by the writer to a study of the manganese ore-deposits of Georgia. A report embodying the results of this study is rapidly nearing completion, and when finished it will be published as a bulletin of the Geological Survey of Georgia. I believe, however, the importance of these deposits warrants a separate and earlier publication than that made possible by the Survey, in which the more important results of the study are briefly set forth. It is principally for this reason that the present paper has been prepared. Previous Work.—Some of the more important deposits of manganese occurring in the Paleozoic area of Georgia were studied to some extent previous to 1890 by Dr. Penrose;t and again in the early nineties by former State Geologist, J. W. Spencer. In a recent paper published in the Transactions, on the " Geological Relations of the Iron-Ores in the Cartersville District, Georgia," Dr. Hayes briefly mentions the manganeseores of the same district. Distribution of the Manganese-Ores.—Georgia is divisible into three geologically-distinct areas which, named in order from southeast to northwest, are (a), the Coastal Plain; (b), the Crys-

Jan 1, 1904

By Robert L. Fleischer

A well known but unexplained experimental fact is the observation1 that aluminum shows a pure <111> wire texture, in contrast with other fcc metals, which have a mixed <100> <111> texture at moderate reductions. A possibly related single crystal observation on aluminum is the following:2 under tensile deformation <111> single crystals are stable (maintain their original axial orientation), while <100> crystals are unstable at room temperature and become stable at lower temperatures. This suggests that at room temperature, as proposed by Yen and Hibbard,3 the single <111> texture obtains be- cause <100> orientations are unstable in the poly-crystal. It also implies that for wire drawing at lower temperature a <100> component of the texture might be expected since that orientation is then stable. This possibility has been examined by wire drawing at temperatures near 77°K. The apparatus was designed to be used with an existing draw-bench, a steel trough acting as die holder and containing sufficient liquid nitrogen to immerse the wire entering the die. The trough is insulated by a styrofoam container to prevent excessive boiling of the bath. The wire emerging from the die enters a polyethylene tube, into the far end of which the grips are inserted. Liquid nitrogen is funneled into the tube to maintain the low tem-

Jan 1, 1962

TULSA, the host of the Petroleum Division this year, is the oil metropolis of the Mid- Continent and gateway of the Southwest. It has risen in less than three decades from a dusty cattle town of less than 1000 population to its present-day status of a modern, wide-awake and prosperous city of close to 150,000, with an assessed realty valuation of approximately $100,000,000. Oil was discovered near Tulsa in 1901, and with it came th.2 development of the Mid-Continent field, one of the richest in the world. Tulsa from the start has been the center of operations, and its location on foul- and aggressive application of the airplane to oil-field requirements tends to fix this status as production is developed farther and farther afield. That Tulsa is far more than an ephemeral oil town is punched into the newcomer&apos;s- especially the Easterner&apos;s-mind, as he is whisked by taxi from the railroad station to the Hotel Mayo. The cicadalike pounding of the riveters on the steel skeletons of many skyscrapers, mounting upward to fill the gaps in an already well-developed skyline, dispels the feeling of a new atmosphere and puts him back on Forty-second Street, Michigan Boulevard or whatever his own particular "Main Street" may be along which an American city is being remade. Practically every company of any importance operating in the Mid-Con-

Jan 1, 1928

By O. J. Malacarne, D. G. Millenbruch

The use of a series of thickeners for washing of the slime fraction of a leached ore is not uncommon in the uranium industry; however, few ore processing mills have used a thickener circuit for washing leached total ore. The common practice is to wash the sand fraction in classifiers and the slime fraction only in thickeners. At the Uravan mill of Union Carbide Nuclear Co., a total ore acid leach is employed to extract uranium values from sandstone ores. These leached ores are then washed at a nominal rate of from 1000 to 1300 tpd in a series of washing thickeners. A typical screen analysis of the ore being washed in these thickeners is: 25 pct, -200 mesh; 3 pct, +35 mesh; and about 1 pct, +14 mesh. The amount of slimes (-200 mesh) will vary from 20 to 30 pct as the mill receives ore from 150 different mines. The washing liquor is acidic, from a pH of about 2 in the first thickener to 0.6 pH in the last thickener and, of course, all acid duty equipment must be used. The Uravan mill of Union Carbide Nuclear Co. is located in Montrose County, Colo. and is physically located on a canyon wall along the San Miguel River. The thickeners referred to in this paper are located on top of the mesa above the canyon. For purposes of identification, these thickeners are numbered 1 through 8 from south to north. GENERAL DESCRIPTION OF CIRCUIT The circuit utilized consists of eight wooden fir tanks, 60-ft diam by 12-ft deep, set in a line and staggered in elevation by approximately 3 ft. The washing water flows through the thickeners by gravity, while the ore pulp is pumped uphill from thickener to thickener. Adequate piping and pumping capacity are available so that any of the thickeners can be bypassed in the circuit. All the controls for the

Jan 1, 1962

By J. J. Rutledge

FULLY 60 per cent of the serious and fatal accidents in Maryland coal mines are due to falls of roof and side. Usually, the victim of the fall sustains a broken back, sometimes not only the vertebrae being fractured but the spinal cord also being severed. When the spinal cord has not been severed and yet the vertebrae have been broken or injured, it is often possible to rehabilitate the victim of the broken back. - Such accidents are classed as Permanent Total and the victim receives a certain compensation from the State Industrial Accident Commission; sometimes the amount is awarded in a lump sum, but usually it is paid weekly. When the amount allotted to the victim of such an accident has been expended, either in a lump sum or weekly payments, the victim of the accident is dependent on public charity. Some efforts have been made to physically rehabilitate the victims and make them at least partly self-supporting before the expiration of their compensation payments. The State Industrial Accident Com-mission has done some of this rehabilitation. The Maryland Bureau of Mines, in cooperation with R. C. Thompson, Supervisor of Vocational Rehabilitation, State Department of Education, and his assistants, has, through an informal cooperative arrangement, placed several of the victims in hospitals in Baltimore for treatment. Six years ago, through the efforts of the Maryland Bureau of Mines, a dozen or more broken-back victims were examined by an orthopedic surgeon and report was made to the Bureau regarding such cases and the possibility of their rehabilitation. This paper details the result of such examinations.

Jan 1, 1936