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Joseph E. Thropp, Jr., Indiana Harbor, Ind.:—To what do you attribute the fact that in some localities the by-product coke sells at a premium over the ordinary bee-hive coke for foundry use ? If the cell-structure is preferably soft and rather thick in coke for foundry use, as I understand it, do you mean that by-product coke has soft and thick cell-walls ? William H. Blauvelt, Syracuse, N. Y.:—As I say in one of the paragraphs of my paper, the tendency seems to be towards the manufacture of foundry- and furnace-coke under somewhat different conditions. The development of the best cell-structure in coke, of course, has not reached perfection, but we are making progress, and we are inclined to believe that under ordinary conditions the best furnace-coke, that is, coke with the hard cell-wall and the well-developed cell, is produced at fast coking-time and high heats, whereas the best foundry-coke seems to be produced at somewhat lower heats. In one of our plants we are making furnace-coke in 16-hr. coking-time, and foundry-coke in 20-hr. time. Foundry-men want the strong, tough coke. I think the furnace-men present will agree that the best furnace-practice requires a hard coke, with a well-developed cell-structure. Replying to the question as to the reason for higher prices being realized for by-product foundry-coke than for bee-hive coke, of course, the immediate reason is that it suits the foundry-men better. Perhaps one cause may be that we are able, by the selection of coals, which is not usually practicable at bee-hive plants, to get a quality and analysis best suited to foundry-work, with high carbon-content, and with cell-structure and physical strength especially suited to the foundry-men's ideas.

Jan 1, 1913

By Georges Fleming

The new burden preparation plant of ARBED Luxembourg, Belval- Works, which comprises 2 large sinter strands, is equipped with a process computer connected to a comprehensive process control system. The main jobs done by the computer are the control of the raw mix composition, and thus the monitoring of the stacking of the piles at the bed-blending plant, and the optimization of the sintering process. Among the optimization criteria, quality is considered as the most important. The sinter quality, characterized by the mechanical strength and the state of oxidation, is controlled automatically. The control system which we have dev loped is highly reliable; as a result, the standard deviation of Fe++, for the control of bivalent iron, has been narrowed to 0,5 % and the standard deviation of the IS0 + 6, 3 mm index, for the control of the mechanical strength, has been kept within 1 %. Thanks to these results, the combined savings in fuel consumption at the sinter plant and at the blast furnaces have covered the total costs of the optimization project in 2 years. By applying automatic control, the optimum driving range of the sinter plant has been defined and these new guidelines are used for monitoring the sinter production.

Jan 1, 1977

RACAL COMMITTEE OF ARRANGEMENTS Henry McCormick, Chairman; David Watts, Secretary; H. H. Campbell, A S. McCreath, S H. Chauvenet, C. E. Stafford, George S. Comstock, Jones Wister, E. C. Felton, F. W. Wood, Harvey Fisher. CITIZENS' RECEPTION COMMITTEE Governor H. M. Hoyt, Hon John C. Herman, Hon Simon Cameron, Hon. J. D. Cameron, W T. Hildrup, Charles L. Bailey, W. W. Jennings, Lane S. Hart, H. U. Carter, Gilliard Dock, T. T Wierman, Jr, James Boyd, D. L. Jauss, Dr. T J. Dunott, S. C. Gilbert. William J Rose, James Lynah, Dr. H. B Buehler, William N Lamberton, John Wister, G. M. McCauley, David Fleming, John Q. Donney, M. E. Olmsted, H. S Gross, Henry Gilbert. John B. McPherson, Lyman D. Gilbert, F. W. Forman, L. S. Bent, A. J. Dull, F. R. Leib, Dr. G. W. Belly, James McCormick. The opening session of the meeting was held in the hall. of the Young Men's Christian Association, on Tuesday evening, October 25th. Mr. Jones Wister, of the Local Committee of Arrangements, introduced the Hon. John C. Herman, mayor, who, in a brief address, extended to the members present a welcome to the city, of Harrisburg ; Lieutenant Governor Stone made an address of welcome on behalf of Governor Hoyt and the Commonwealth of Pennsylvania. President Metcalf responded, on behalf of the Institute, to the cordial addresses of the mayor and lieutenant-governor. The following persons proposed for members and associates of the Institute, and recommended by the Council, were unanimously elected :* MEMBERS. William F. Aldrich, - Montevallo, Shelby Co., Ala. George H Blake, - Steelton, Dauphin Co., Pa. L. Bertram Cady, - Salisbury, N. C. John B. Church, - Pottsville, Pa. Walter S. Church, - Pottsville, Pa, Frank L Clark, - Pittsburgh, Pa. * In the following list are included those elected at a subsequent session of this meeting.

Jan 1, 1882

By M. D. Hassialis

THE object of a technical paper is to communicate new technical knowledge, the paper being the vehicle of communication and the existence of new knowledge its reason for being. It follows that the development of information worthy of communication, the criterion being novelty, is prerequisite to exercising the privilege of communication. The act of communication is achieved when the reader perceives the nature of the new knowledge, i.e., when he understands it. A paper achieving this objective is an acceptable technical paper. Development of new knowledge has as one of its purposes the increase of the existing state of knowledge and the enjoyment of the benefits derived therefrom. Technical knowledge is a collection of facts so ordered as to make apparent, relations existing between the facts. When the interrelations have been exposed the facts have been interpreted or explained Three broad, overlapping categories of technical papers may be recognized: papers consisting of (a) a report of facts, (b) an explanation of facts, or (c) a combination of a report and an interpretation. Ideally a technical paper should belong to one of the last two categories but current practice is to accept papers belonging to any of the three categories. Based on a small sample drawn from the scientific and engineering literature, the relative frequency of the three types is a: b: c:: 20:1:14. If the sample be limited to engineering literature, the ratios become a:c::2:1; type (b) being nonexistent. This large departure from the ideal is a consequent of the

Jan 1, 1948

By P. J. Closmann

Steam zone growth as a function of time has been calculated for the case of constant rate steam injection into a preheated reservoir. To simplify the calculation a linear temperature profile has been assumed in the cap and base rock at the start of steam injection. The results indicate that at early times augmentation of steam zone growth due to preheating should be greatest. At longer times the steam zone development becomes close to that calculated with no preheating. INTRODUCTION With the increasing application of thermal recovery processes to recover viscous oil, cyclic steam injection has become important in many large-scale projects. In this process, the cycle of steam injection followed by oil production is repeated a number of times. At the beginning of the second and later cycles, steam is injected into a reservoir that has already been heated but that has lost part of its heat both in produced fluids and by conductive heat loss away from the injection zone. In such a case, the temperature level of the injection zone and the temperature distribution of the surrounding rock will affect the growth of the steam zone developed during the subsequent steam injection. Knowledge of the size of steam zone developed is important in determining the amount of oil displaced and the extent of heating in the reservoir. It is also useful to be able to compute the size of the steam zone for cases where thief zones take most of the injected steam. This paper presents a fairly straightforward method of estimating the steam zone developed in a preheated formation, based on certain simplifying assumptions. Some cases of steam injection into a reservoir at its original temperature have already been considered elsewhere.1-3 Because it is difficult or impossible to obtain an accurate representation of the temperature distribution in the reservoir some time after initial heating has taken place, in this work, a linear temperature profile in the cap and base rock is assumed (Figs. 1A and 1B). The linear profile has the advantage of yielding heat flow equations that

Jan 1, 1969

By W. T. Turrall, D. Porter

THE crystal laboratory, Dept. of Physics, Massachusetts Institute of Technology, was confronted with the problem of obtaining a supply of optical grade calcium fluoride (CaF2) for use in growing synthetic CaFe2 crystals. A search of the known fluorspar deposits did not indicate that any quantity of optical spar could be obtained. Even the best material had to be sorted by hand to remove impurities. The process for growing CaF2 crystals developed by Professor D. C. Stockbarger of the Dept. of Physics, M.I.T., necessitates very pure feed materials. Exclusion of impurities is required, even in amounts detectable only spectrographically. The impurities occurred as minute inclusions of SiO2, BaSO4, CaCO3, FeS2, water or air. Crystals up to 4 in. in diam and weighing several pounds are made by the Harshaw Chemical Co. in Cleveland. Since the time required to grow a 4-in. crystal is about one week, and since the cost of manufacture is high, removal of impurities by any concentration method appeared practical. The mineral engineering section of the Dept. of Metallurgy undertook to investigate the possibility of concentrating clear optical fluorspar, -4 mesh +10 mesh, from a feed containing over 99 pct CaF2. Various innovations of the known methods of concentration were considered, but in each case the minute amount of impurities associated with the crystal produced such extremely small differences

Jan 1, 1952

By Frank R. Van Horn

In the summer of 1908, R. B. Cochran, Superintendent of the Compania Metalurgica Mexicana at Sierra Mojada, Mexico, presented to the Department of Geology and Mineralogy at Case School of Applied Science an interesting series of silver-, copper-, and lead-ores from the Veta Rica mine. These ores contained several interesting minerals which were associated in a somewhat peculiar manner, so that I was impelled to make a closer study of their occurrence. The investigation has brought out several new facts concerning the geology of the district and the geological occurrence of the ores, and therefore has seemed worthy of record. Two papers have been published previously about the region, one by Chisml in 1887, and the other by Malcolmson² in 1902. These articles, however, treat of the district more from the stand-point of the metallurgist and mining engineer, and not much attention is devoted to its mineralogy and economic geology. 11. Geographical Location of the District. The Sierra Mojada is situated in the extreme western part of the State of Coahuila, near the Chihuahua boundary. It is reached best via the Mexican Central railroad from El Paso, Tex., to Escalon, Chihuahua, a distance of 494 miles. From this point, a branch line, the Mexican Northern railroad, runs 78 miles in a NE. direction to the mines, which are its northern terminus. The railroad was built about 1890, practically on account of the Sierra Mojada mining-district.

Jan 1, 1913

By J. S. Kirkaldy, W. V. Youdelis

THE occurrence of concentration distributions in rapidly cooled castings with gradients of opposite sign to those expected on the basis of the constitution diagram and diffusion controlled kinetics, has long interested metallurgists. The work on inverse segregation to 1937 has been adequately reviewed by Vaughan, and to 1949 by ell-walpole. The general conclusion for unidirectional solidification, that the enrichment of the initially solidifying regions with lower melting point compositions is due to the flow-back along interdendritic channels of normally segregated residual liquid, has a very sound experimental basis. Perhaps the best experimental work and the most complete qualitative description of the process has been given by Adams.3 The authors accordingly assume the reader's understanding of the content of this paper. It appears that one of the principal deterrents to the complete understanding of the process has been the lack of an analytical description. Although a number of workers including Masing,4-6 Sauerwald,7 and Adams3 have attempted quantitative predictions,

Jan 1, 1959

By B. K. Miller, R. S. Bradley

THE principal producing areas of fire clay in Missouri are: (I) the east central district, which includes Audrain, Callaway, Montgomery, Warren, and Boone Counties [ ] (Fig. I); (2) the St. Louis district, which includes St. Louis and St. Louis County; (3) the north central Ozark district, which includes Franklin, Gasconade, Osage, Maries, Phelps, and Crawford Counties. Most of the semiplastic[$] fire clay is found in Audrain, Callaway, Montgomery and St. Louis Counties, and in St. Louis. Flint fire clay is found in Callaway, Audrain, and Montgomery Counties and in most of the north central Ozark district. High-alumina diaspore clay is found only in the north central Ozark district, except a few deposits found in Montgomery County. This paper is concerned with the semiplastic fire clay that occurs in the east central Missouri district near Mexico, Audrain County, Missouri, which is mined by the open-pit method as practiced by the A. P. Green Fire Brick Co. About one-fourth of the semiplastic fire clay in that district is mined in shaft mines, and three-fourths in open pits.

Jan 1, 1941

By R. S. Bradley, B. K. Miller

The principal producing areas of fire clay in Missouri are: (I) the east central district, which includes Audrain, Callaway, Montgomery, Warren, and Boone Counties (Fig. I); (2) the St. Louis district, which includes St. Louis and St. Louis County; (3) the north central Ozark district, which includes Franklin, Gasconade, Osage, Maries, Phelps, and Crawford Counties. Most of the semiplastic‡ fire clay is found in Audrain, Callaway, Montgomery and St. Louis Counties, and in St. Louis. Flint fire clay is found in Callaway, Audrain, and Montgomery Counties and in most of the north centra! Ozark district. High-alumina diaspore clay is found only in the north central Ozark district, except a few deposits found in Montgomery County. This paper is concerned with the semi-plastic fire clay that occurs in the east central Missouri district near Mexico, Audrain County, Missouri, which is mined by the open-pit method as practiced by the A. P. Green Fire Brick Co. About one-fourth of the semiplastic fire clay in that district is mined in shaft mines, and three-fourths in open pits.

Jan 1, 1942

By B. K. Miller, R. S. Bradley

The principal producing areas of fire clay in Missouri are: (I) the east central district, which includes Audrain, Callaway, Montgomery, Warren, and Boone Counties (Fig. I); (2) the St. Louis district, which includes St. Louis and St. Louis County; (3) the north central Ozark district, which includes Franklin, Gasconade, Osage, Maries, Phelps, and Crawford Counties. Most of the semiplastic‡ fire clay is found in Audrain, Callaway, Montgomery and St. Louis Counties, and in St. Louis. Flint fire clay is found in Callaway, Audrain, and Montgomery Counties and in most of the north centra! Ozark district. High-alumina diaspore clay is found only in the north central Ozark district, except a few deposits found in Montgomery County. This paper is concerned with the semi-plastic fire clay that occurs in the east central Missouri district near Mexico, Audrain County, Missouri, which is mined by the open-pit method as practiced by the A. P. Green Fire Brick Co. About one-fourth of the semiplastic fire clay in that district is mined in shaft mines, and three-fourths in open pits.

Jan 1, 1942

By B. K. Miller, R. S. Bradley

THE principal producing areas of fire clay in Missouri are: (I) the east central district, which includes Audrain, Callaway, Montgomery, Warren, and Boone Counties [ ] (Fig. I); (2) the St. Louis district, which includes St. Louis and St. Louis County; (3) the north central Ozark district, which includes Franklin, Gasconade, Osage, Maries, Phelps, and Crawford Counties. [ ] Most of the semiplastict fire clay is found in Audrain, Callaway, Montgomery and St. Louis Counties, and in St. Louis. Flint fire clay is found in Callaway, Audrain, and Montgomery Counties and in most of the north central Ozark district. High-alumina [ ] diaspore clay is found only in the north central Ozark district, except a few deposits found in Montgomery County. This paper is concerned with the semiplastic fire clay that occurs in the east central Missouri district near Mexico, Audrain County, Missouri, which is mined by the open-pit method as practiced by the A. P. Green Fire Brick Co. About one-fourth of the semiplastic fire clay in that district is mined in shaft mines, and three-fourths in open pits.

Jan 1, 1941

By Jan Wolski

Today's rapidly shrinking world requires a common language of measurements, a consistent system which could be used by everyone. The S.I. system of units is generally accepted as such and is already in use by a great majority of nations in the world. The change to S.I. units is also slowly taking place in U.S. engineering practice. The transition period is difficult and long because it takes time to get familiar with the new system, to start "feeling" values in new units. Instruments, formulas, computer programs, survey grids, etc. have to be converted or exchanged. The transition period should be used not only for substitution of units, but also for rationalization of presently used calculation methods. This paper examines the major parameters of mine ventilation from the above point of view and discusses a system which is much simpler and more consistent than the American Unit System still in use in the United States. In October 1979, the Society of Mining Engineers of AIME decided to introduce the S.I. unit system in all its publications including the periodical "Mining Engineering", and since February 1980 the system has been used consistently, not only in SME publications but in all conferences and meetings organized by this Society. The authors have no intention of explaining the details of the S.I. system in general. Any reader can find this information in many available publications and conversion tables, and in particular in the ASTM Standard for Metric Practice, E380-79. A comparison is made between various units used in mine ventilation from the past and those presently in use. This will allow an easy translation from one system to another, important when reading publications from abroad. S.I. and customary U.S. formulae are shown side by side for easier visualization of similarities and differences. Recommendations for the necessary steps in order to switch from American to S.I. units conclude the paper.

Jan 1, 1982

By L. C. Graton

The federal taxes on incomes and excess profits are of course heavy. In 1917, the value of the mineral production of the United States was a little in excess of $5,000,000,000. The total of federal taxes for that year, for the mineral producing companies, as computed by themselves, amounts, according to tentative compilations, to about $207,000,000, and the total for the comprehensive group of mineral and metal industries to about $766,000,000, which figures represent respectively 9.5 per cent. and 35.1 per cent. of the total tax paid by all corporations. Because of greater complexities in applying the revenue laws to mineral properties than to most other industries, opportunity is afforded for wide differences of view. The taxes indicated above, therefore, are not final and may conceivably be very materially increased. For 1918, the taxes are expected to be still greater, but no compilations are yet available. Taxes at a high rate are to continue indefinitely. The subject is clearly of gravest import to the mining industry in particular. The Commissioner of Internal Revenue, who is charged by law with the administration and collection of the taxes, is determined that these functions shall be performed in a just and businesslike way. Fairness and finality are to be the chief objectives. In view of the peculiar conditions that attach to the tax program as applied to mines and other wasting industries, like oil, gas, and timber, the Commissioner has resorted to professional advice and assistance by manning a Sub-division of Natural Resources with competent engineers, brought in from the several industries, into whose hands he has placed for solution the technical questions involved. These engineers have a two-fold duty: (1) to devote to the solution of these problems their own knowledge and experience; (2) through their acquaintance with their respective industries, and with the men engaged in those industries, to focus upon these problems, by conferences and otherwise, the best opinion of the country. The principal object of this paper is to acquaint the mining profession with the attitude of the

Jan 1, 1923

By L. C. Graton

The federal taxes on incomes and excess profits are of course heavy. In 1917, the value of the mineral production of the United States was a little in excess of $5,000,000,000. The total of federal taxes for that year, for the mineral producing companies, as computed by themselves, amounts, according to tentative compilations, to about $207,000,000, and the total for the comprehensive group of mineral and metal industries to about $766,000,000, which figures represent respectively 9.5 per cent. and 35.1 per cent. of the total tax paid by all corporations. Because of greater complexities in applying the revenue laws to mineral properties than to most other industries, opportunity is afforded for wide differences of view. The taxes indicated above, therefore, are not final and may conceivably be very materially increased. For 1918, the taxes are expected to be still greater, but no compilations are yet available. Taxes at a high rate are to continue indefinitely. The subject is clearly of gravest import to the mining industry in particular. The Commissioner of Internal Revenue, who is charged by law with the administration and collection of the taxes, is determined that these functions shall be performed in a just and businesslike way. Fairness and finality are to be the chief objectives. In view of the peculiar conditions that attach to the tax program as applied to mines and other wasting industries, like oil, gas, and timber, the Commissioner has resorted to professional advice and assistance by manning a Sub-division of Natural Resources with competent engineers, brought in from the several industries, into whose hands he has placed for solution the technical questions involved. These engineers have a two-fold duty: (1) to devote to the solution of these problems their own knowledge and experience; (2) through their acquaintance with their respective industries, and with the men engaged in those industries, to focus upon these problems, by conferences and otherwise, the best opinion of the country. The principal object of this paper is to acquaint the mining profession with the attitude of the

Jan 1, 1923

By C. P. Besse, N. F. LeBlanc

Described in this paper are oceanographic data which should be considered by an offshore design engineer and methods for developing a design wave height from the oceanographic data. The selection of a design wave is predicated on contemplated waves which might affect the site throughout the life of the structure. Selection of a design wave height may be based on (1) arbitrarily established recurrence Frequencies of hurricanes affecting the structure (predicted wave heights are associated with the expected variations of forces resulting from these waves) and (2) a risk-type evaluation wherein all possible storms affecting the area are considered (anticipated wave heights are associated with both investment plus risk costs and expected variations of forces). It is shown how the following oceanographic predictions are integrated into design considerations: (1) a classification of storm intensity which considers all recorded storms which affected the design area, (2) the recurrence interval of storms of a given- intensity (this interval is dependent on the extent of the geographical area considered in the design problem) and (3) a forecast of all wave heights which might affect the area (geometry of a structure often necessitates consideration of waves from a multiplicity of directions). The authors believe that the described techniques can result in selecting an adequate and reasonable design wave. INTRODUCTION Since the inception of offshore operations in the Gulf of Mexico, engineers engaged in designing suuctural facilities have been plagued with the problem of selecting an adequate and reasonable design wave. In the development of any offshore structure it is mandatory that the engineer evaluate the ability of the structure to withstand the ocean waves to which it will be subjected. Selecting such design waves quite naturally necessitates a coalition of the oceanographer and the design engineer. The oceanographer must provide a detailed knowledge of scientific principles which govern the behavior of waters in the Gulf of Mexico. He should also have an adequate knowledge of the manner in which design waves are utilized by the engineer. Although the design engineer's primary responsibility is applying the oceanographer's specialized knowledge in the creation of real structures, it is important that he possess some knowledge of related oceanographic principles to reasonably evaluate and apply the recommendations of the oceanographer. In the Gulf of Mexico it is the hurricane wind waves which generally govern the design of an offshore facility. The oceanographer must therefore develop techniques for predicting the heights, periods and frequency of all hurricane waves which might affect a particular structure. From this mass of oceanographic data, the design engineer must select the design waves which will apply to his particular design. PAST STUDIES ON FREQUENCY AND AMPLITUDE OF HURRICANE WIND WAVES Past oceanographic studies on the frequency of hurricane wave heights in the Gulf of Mexico have been devoted largely to predicting the recurrence interval of hurricanes which will generate maximum significant waves of given heights. The maximum significant wave height is the average height of the highest one third of the waves in that portion of the storm producing maximum wave heights. Since these waves occur over a relatively small portion of the storm (Fig. 1) and since the paths of hurricanes vary considerably (Fig. 2), the recurrence frequency of such heights is largely a function of the extent of the geographical area considered. In establishing the frequency of maximum significant waves for the entire American Gulf coast, the major fully developed hurricanes which affected the coastline from BrOwnsville, Tex., to Key West, Fla., were considered (Fig. 2). These Storms were selected and described by C. L-

A week-long educational program and two-day symposium on applying the fluidizing reactor to the minerals industry drew more than 100 engineers to the University of Arizona at Tucson several weeks ago. The educational program, intended for engineers who will work closely with the reactor, attracted registrants from all sections of the U. S. and Canada. Meeting at the College of Mines on February 23 for a full week of intensive classwork, the engineers ploughed in with enthusiasm. Eight hours daily of lectures and laboratory work were followed by a generous helping of homework supplied by Professor Sigmund L. Smith, who directed the course. The study program was completed on Friday and the following Monday marked the start of a symposium of technical papers covering a wide variety of operations and new ideas.

Jan 4, 1959

By George S. Rice

The extremely valuable papers and discussions on coal-cluat explosions by Bache,' Eavenson, Shurick, Mannakee,* and Raymond are of unusual interest to me, since it has been my duty to carry on investigations on this and allied subjects for the Technologic Branch of the United States Geological Survey during the past year, and to make a series of coal-dust tests in the explosion-gallery at Pittsburg during a short periocl when its use could be diverted from the pressing work of testing explosives. In several of the discussions mentioned, it has been assumecl that the Technologic Branch of the Survey mas not paying attention to certain phases of the general problem, or to the specific question of temperature and humidity of mine-air in its effect upon the explosibility of coal-dust. This assumption is not correct, since from the time of the establishment of the " Mine-Accident Division," with its subdivisions of explosives, rescue-work, and mine-investigation, the mining engineer.; of the last-named section have made the subject one of chief consideration. Their general duties, including mine-sampling for governmeilt purposes, emergency-calls for rescue-work, and esplosion investigations, have prevented undivided attention, but all of them have been supplied with instruments for such determinations, and special report-forms have been in use and a great many observations made in mining-districts to which the mining engineers have gone. With the idea of obtaining a uniform system of reporting these data, and in the hope that the work may be of service to mining engineers in the field, the collecting blanks in use are shown in Forrns 1 and 2.

Jan 1, 1911

By William Griffith

THE purpose of this paper is to make public record of new information in regard to the sustaining power of artificial mine-roof supports (not timber props) the result of investigations recently made in the anthracite coal fields of Pennsylvania. First.-By the "Scranton Mine Cave Commission," appointed to investigate the mining conditions under the City of Scranton. Second.-By the "Pennsylvania Mine Cave Commission," appointed by the Governor to investigate the general subject of mine caves in the anthracite region of Pennsylvania. Third.-By the personal researches and tests made by the author in an effort to secure a better artificial mine-roof or surface support. During the progress of the work of the Scranton Mine Cave Commission, the Engineers for the Commission, Messrs. Conner and. Griffith, being aware of the general lack of exact information in the engineering profession as to the strength of the ordinary artificial mine-roof or surface support, and particularly the stronger kinds, such as mine cogs, rock piers, etc., had tests made at the. Fritz Engineering Laboratory at Lehigh University, to determine the sustaining power under various compressions of the several kinds of artificial mine supports in use in the anthracite region of Pennsylvania. A report of these tests was included in the report of this Commission, which was published as Bulletin No. 25 of the United States Bureau of Mines, Washington. A similar series of tests, more extensive and more elaborately-planned, were subsequently made for the Pennsylvania Mine Cave Commission at the U. S. Government Testing Laboratory at Pittsburgh, Pa. The report of this Commission was made to the Governor, but has not yet been published.

Jan 10, 1917

By A. J. Lanea

INDUSTRIAL MEDICINE bids fair to become one of the most important and highly developed branches of medical science. Mining companies, even in remote districts, have developed large and efficient medical organizations that comprise the best types of physicians and surgeons. Not infrequently, however, company medical departments have been influenced too much by local conditions-including the compensation laws, which differ widely in the various states. The possibilities of industrial medicine are just beginning to be generally understood, and the variations in the organization and aims of medical departments of mining companies are no more pronounced than in industry as a whole. The industrial physician should be as much a part of the organization as any other official and he should know intimately the various types and phases of work in the plant and should look at his work from the viewpoint of the needs and requirements of his particular industry and company. He should not-be on the outside looking in, but on the inside, working hand in hand with the superintendent, manager, foremen, employment director, safety director, and anybody else with whom in his work he might associate. In any industry it is essential that the doctor be-familiar with working conditions. The mine doctor who never goes underground must remain ignorant of the factors causing many of the disorders he treats as well as miss the best opportunity of gaining the respect and cooperation of the men he. serves. If the mine doctor remains unfamiliar with underground working conditions he bars himself from valuable preventive medical work. It is estimated that the time lost by industrial workers, as a whole, because of illness is about four times as great as that lost because of accidents. While the effort to determine the responsibility of working conditions for illness is often futile, there is a wide field, both for study and practice, in the lessening of sickness among industrial workers. The first step in this direction must be a knowledge of the factors involved.

Jan 2, 1921