Search Documents

President Heiner opened the final session of the Institute at 9:30 a.m. Frances Leonard read the report of the Auditing Committee. Motion made by Stan Shubart for acceptance of audit and approval. Seconded and carried. R. R. Williams of the Resolutions Committee presented the following resolutions to the, group for their approval: RESOLVED: That the members of the Rocky Mountain Coal Mining Institute, in convention assembled, hereby ratify and confirm all official actions of the Officers, the Executive Committee and other committees of the Institute between and including July 3, 1963 and July 1, 1964.

Jan 1, 1964

Amercable, Inc. Andalex Resources, Inc. ARCO Coal Company Behre Dolbear & Company, Inc. Colowyo Coal Co. L.P. Continental Conveyor & Equipment Company Crane & Hoist Sales Crested Butte Mountain Resort Cyprus Amax Coal Co. Energy West Mining Company The Falkirk Mining Company Fleischli Oil Co. Inc. Halbach & Braun Industries Hemscheidt Corporation GH Henley Industries Ingersoll-Rand Co. Jennmar Corporation Joy Technologies, Inc. K & P Sales Engineers, Inc. Kennametal, Inc. Kerr-McGee Coal Corporation L & H Welding & Machine Co. McLanahan Corporation National Coal Association The North American Coal Corporation Northwestern Resources Company Peabody Western Coal Company Phillips Machine Service Pincock Allen & Holt Ramsey Technology, Inc. Rust Tractor Company Salt River Project Schroeder Industries Stamler Corporation TerraMatrix TIC (The Industrial Company Wyoming, Inc.) Trapper Mining Inc. Wagner Equipment Company Western Energy Company Wheeler Machinery Company

Jan 1, 1994

By Mike Onsager

Jan 1, 2006

The Annual Meeting of The Rocky Mountain Coal Mining Institute was called to order by the President, John T. Atkins, at 2:00 p.m. Tuesday, June 26, 1984 in the Colorado Ballroom of the Marriott's Mark Resort in Vail, Colorado. There were 36 members in attendance. It was moved by Bob Diederich, seconded and carried to dispense with the reading of the 1983 Annual Meeting minutes as printed on pages 105 thru 109 of the 1983 Proceedings. In keeping with the printed agenda in the convention program/ticket booklet, the President called for reports of standing committees as follow: 1. Bylaws & Resolutions - Loren Linville, Chairman Linville noted that the committee had been working for two years on bylaws changes and concluded a corporate lawyer specializing in nonprofit organizations be engaged. He then introduced Mr. Peter B. Nagle of the Denver law firm of Sherman and Howard who outlined the major changes in converting the Institute's current status of 501(c)(6) to 501(c)(3). He pointed out that such a conversion would give the Institute a proper legal status, would give individual contributors to the scholarship or other programs a personal income tax deduction, would qualify the Institute for the postal nonprofit mailing rate and the Institute would achieve the advantage of limited liability inherent in a corportion and would insulate its members, officers and directors from liability for corporate obligations. Copies of the Articles of Incorporation as well as the Bylaws were available for all members. A discussion ensued and the following resolution was moved by Bob Diederich, seconded and carried: RESOLVED, that the unincorporated association known as the Rocky Mountain Coal Mining Institute be, and hereby is, dissolved and in its place, and to carry out its objectives, shall be formed a nonprofit corporation under the laws of the State of Colorado, which corporation shall also be known as The Rocky Mountain Coal Mining Institute, and to which shall be transferred all of the assets and liabilities of this association. FURTHER RESOLVED, that the proper officers of this association are authorized and directed to execute and file with the Colorado Secretary of State, Articles of Incorporation in a form substantially similar to those prepared for this association by its counsel, and the names of the individuals identified in such Articles of Incorporation as the initial Board of Directors of such corporation, which names were proposed and recommended by the Nominating Committee of this association, are hereby approved. FURTHER RESOLVED, that the proper officers of this association are authorized and directed to do all acts necessary or convenient to carry out the terms of the preceding resolutions. (Articles of Incorporation and Bylaws as adopted are printed following these minutes.) Additional resolutions were read by Linville as follows: Item 1: WE RESOLVE herein that in the year since the last convention of the RMCMI, the Institute and the coal industry have suffered the loss, through death, and the services of: Lloyd W. Taylor Charles T. Holland THEREFORE, BE IT RESOLVED, that we record in the minutes of the RMCMI, recognition of the passing of these members who have so greatly contributed to the advancement of the industry, both nationally and in the Rocky Mountain area, and that a copy of this resolution be sent to the next of kin as evidence of the sincere sympathy and deep regard of the members of the Institute. Item 2: RESOLVED, that in recognition of their long and faithful service to the coal industry that the status of Life Member be conferred upon: Bernard Bernstrom Roy Coulson Shirl C. McArthur Item 3: RESOLVED, that we commend and express our gratitude to our Executive Secretary, officers, chairmen and committees for an outstanding job in presenting. the 80th RMCMI meeting. Item 4: RESOLVED, that the RMCMI express its gratitude to K&P, INC. of Golden, Colorado for their generous donation of office facilities and furniture for the RMCMI office and to K&P SALES ENGINEERS, INC. also of Golden, Colorado for their assistance in telephone answering, other office procedures and the use of certain office equipment. Item 5: RESOLVED, that six scholarships be awarded annually to advance the education program of the Institute to worthy students pursuing career paths in mining or other related industry in the six states in which the Institute generally operates and has members and in accordance with the criteria set forth by the Scholarship Committee. It was moved by Jim Neal, seconded and tamed

Jan 1, 1984

President Robert M. von Storch called the meeting to order at 9:00 A.M., and introduced the first speaker of the MANUFACTURERS' HOUR. D. M. Stromquist, Technical Representative, Coal Chemical Sales Division, United States Steel Corporation, Salt Lake City, Utah, presented a paper, "Ammonium Nitrate and Its Use as a Blasting Agent," which was illustrated with a number of slides. (See Index.) President von Storch introduced Kenneth J. MacLeod, Socony Mobil Oil Company, Denver, Colorado, who gave a short paper on "New Greases." Following are excerpts from Mr. MacLeod's talk: The recent advances in machinery, and their continuing development present a never ending challenge to the oil companies to develop new and better oils. Over the years, industry's machinery has been pressed to meet higher production rates, which has subjected the machinery to increased speeds, temperatures and pressures. Lubrications have had to be designed for a wider range of use. The entire industry has attempted to produce a good product for this extra-duty need. Most greases have contained lead in the past, and especially the food industry has had to be most careful in the use of this around food products.

Jan 1, 1958

Pictured on these pages are the seven RMCMI Scholarship Award Winners for the 1987-88 year followed by a brief profile. Six of the winners were present as RMCMI guests at the June convention in Breckenridge, Colorado to receive their recognition plaques at the welcome session held Monday, June 27, 1988. In addition to the plaques, each winner receives $500.00 to be used toward tuition in the coming academic year. Also, as this is a continuing award, the winners from the previous year will also receive an additional $500.00 for tuition use in their senior years provided they have maintained a good academic standing and are recommended by their university. Criteria for these awards is (1) That the award be made in the spring to a sophomore student to be used toward tuition during the junior year. (2) That the recipient be both a U.S. citizen and a resident of the state involved. (3) That the recipient have good academic standing, be pursuing a degree in a mining related field and have an expressed interest in Western coal as a possible career path. The scholarship program was extended in early 1988 to include curricula other than mining department, but in the engineering disciplines, such as geology, mineral processing and metallurgy. Contributions to this worthy project are tax deductible to each individual RMCMI member. Checks payable to RMCMI Scholarship may be mailed to the RMCMI Office at 2700 Youngfield Street, Suite 100 in Lakewood, CO 80215. Profiles of the 1988 winners follow: [ ] Anthony T. Bowler University of Arizona Tucson, Arizona Tony has taken a well balanced curriculum and at the same time maintained significant progress toward a Geological Engineering degree. He is interested in computer science and programs as a hobby He is the master of several computer languages including machine language on different personal computers. [ ] Christopher Taylor Colorado School of Mines Golden, Colorado Before matriculating at Mines, Chris served four years with the U.S. Army Special Forces attaining the rank of sergeant. He is active in the military, serving in the Reserves and R.O.T.C. This duty precluded his attendance at the Breckenridge meeting. He plans to get summer work experience in mining before graduation and is interested in the managerial and technical aspects of the mining business. [ ] Laverne West New Mexico Institute of Mining & Technology Socorro, New Mexico A native American of Laguna/Navajo ethnic origin, Laverne graduated from the Sante Fe Indian School as valedictorian. She served as both secretary and president of the American Indian Science & Engineering Society. She works at the Nevada Test Site with contractors assisting project engineers in a variety of jobs. She plans to earn a dual degree in Mining and Geological Engineering then pursue a Master's degree in Mineral Economics at the University of California at Berkeley. Among her honors are a four year scholarship from Sante Fe Southern Pacific Foundation, a one year scholarship from Mobil Oil Corporation and another from Eastman Kodak.

Jan 1, 1988

PRESIDENT LITTLEJOHN: We have with us a gentleman from Utah, who is familiarly known -as the "Mudite King," Mr. Reid, of the Lion Coal Company. Here is a letter I would like to read, and probably Mr. Reid will give us an idea of his Mudite machine, or the results he is obtaining. This question was brought up in Rock Springs, Wyoming, but Mr. Reid was not there personally during the discussion, but Mr. Burnell, who is general superintendent of the Lion Coal Com¬pany, as much as he possibly could, described the system and its effects. I believe Mr. Reid will probably be able to give a somewhat clearer statement this afternoon. This letter is from the Coal Mining Inspector of the State of Utah, John Crawford. "February 10, 1925. "The Industrial Commission of Utah, Building. "Statement of John Crawford, Coal Mine Inspector, in regard to Muditing in Coal Mines: "That Muditing used in connection with our present sprinkling system in coal mines is the missing link to the system we have had heretofore, because the water applied by the former system began to dry out, in heavy air currents, the moment it was put on. Consequently the dust that had been humidified by sprinkling, came back to its natural condition, and if anything, the combustible parts of it, in my opinion, were more intensified than previous to being wetted down. "The advantages that Muditing has over the old system of sprinkling are: "1st. The dust that is on the roof, timbers and sides of the entry is washed completely off and rolled up in the Mudite solution which entirely destroys the wings, crudely speaking, of the fine coal dust. "2nd. Sprinkling with the Mudite system, the water and mud is of greater extent than could be applied with a hand hose by a sprinkler. This sprinkling can be done while the mine is in operation, just the same as if water alone was being used. "3rd. The Mudite solution, when dried out, leaves a coating which serves as an armour to the coal, so that in the event of a local explosion, the inflammable matter on the coal is non-combustible; whereas, if that same coal had been sprinkled with water only, and made free of dust, the heat would have the same effect on the coal as it has on a stove when coal is thrown into it-instantaneous combustion. "Therefore, it is my opinion that the Mudite system is the missing link to the perfecting of our sprinkling system here in Utah. "(Signed) JOHN CRAWFORD." Mr. Reid has with him a few sam¬ples of his Mudite, after it has become solidified, taken from the floor, as I understand it. It is interesting. We have a few minutes to spare to good advantage, were we to ask Mr. Reid to give us an idea of his machine, as briefly as he possibly can, and also what he thinks the effect of the Mudite is compared to dry rock dust. Mr. Reid. (Applause.) MR. W. J. REID (Lion Coal Company) : I came down here with no intention of making any talk on Mudite. However, there being so many people that have seen Mudite at Wattis

Jan 1, 1925

By Christopher Blazek

Presentation Overview ?2005 Train Derailments ?BNSF Investigation and Remediation ?BNSF Test Program ?Test Results ?BNSF Dust Control Goals ?National Coal Transportation Study ?Comparison of Different Topper Agents ?What Constitutes a Topper Program

Jan 1, 2008

By William M. Wallace

Mr. Chairman and Gentlemen: The subject, "Shake It for Results," may or may not suggest just what is to be shaken, or just what results are to be obtained. I can assure you that if you are thinking about anything outside the realm of pure mining application you have come to the wrong meeting, and if this be the case, you have come to hear a subject discussed that I am not prepared to undertake-at the moment, at least. At the very beginning of time, results were definitely obtained by shaking. If you will recall, Eve shook a certain tree of forbidden fruit-need I recount to you the results that were, and are still, being credited to that bit of engineering? To get closer to the subject at hand, it is the intent of this paper to touch generally on the shaking, principally the vibratory shaking, of materials on a piece, or pieces, of perforated metal or screen cloth. Through the evolution of such a motion we find that great strides have been made toward a highly efficient "operation which is an essential factor in the mining world of today. The object of the shaking motion is to more efficiently separate one size material from another, according to the openings in the screening medium over which it is passed. Sizing is an important operation in every ore dressing, coal prepara¬tion or other mineral-preparing plant for reducing the product to a form more concentrated or more convenient for utilization than that in which it was mined. In coal preparation, market requirements, convenience, custom, and efficiency in combustion necessitate grading mined coal by sizes. All ore-dressing or coal preparation plants therefore must have what is called screening, sizing, or grading apparatus.

Jan 1, 1941

By Michael A. Poling

Ladies and gentlemen, I appreciate this opportunity to be with you, and to share my outlook on the future of Federal coal leasing. I'm told that you wanted the best speaker on this subject in the world. Perhaps it's a reflection of these trying financial times, but I'm glad you finally agreed to settle for the best speaker your budget would afford. I have been asked to give you some insight on the status of Federal coal leasing, and how the budget problems facing the Department will affect the coal program. So I've polished up my crystal ball, and I'll try to give you a peek at the future. Before I do that, however, let me first go back in time - to when this Administration took office in 1981. We had a coal program then, after a hiatus of ten years. But that program was untested and - for reasons well known to all of you - did not work well in practice once we began operating the program. We went back to the drawing board and redesigned the program so that it can do what it is intended to do. We've made the program more predictable. That means that when future lease sales are scheduled, those sales will be reflective and reactive to the need to lease coal. On February 26, Secretary Hodel unveiled a framework for resumption of Federal leasing program activities, ending a more than two-year suspension of regional coal sales. The new program will provide the opportunity to satisfy market demand for acquiring and developing new leases, assure the government of fair market value for its coal reserves, and provide a stable supply of coal for this country's energy needs. The new program grew out of the Department's response to recommendations of the Linowes Commission and the Office of Technology Assessment, coupled with a supplemental environmental study. The Linowes Report, issued in 1984, contained 36 recommendations and three Judgments on leasing levels, tract selection, sale procedures, appraisal methods, key statutory and related factors, and organization and management of the leasing program. Major changes in the new leasing program reflect these concerns. We have developed a definition for captive tracts and devised procedures to appraise their value to the adjacent coal or mine owner. Other steps include a coal lease appraisal guide which describes our appraisal methodology and is available to the public. Improvements have also been made in the gathering of lease assignment information to help in estimating the value of potential lease tracts. To improve market analysis, a three-tiered system will be used to ensure that steps of the lease sale decision process are undertaken in the context of coal supply and demand. Regional Coal Teams will thus have the advantage of long range, regional and tract specific market studies to help them determine whether sufficient demand is expected first to warrant the initiation of activity planning, then to set regional leasing levels, and finally to actually offer specific tracts for lease sale. Sale procedures will also be improved in many ways to encourage competition, improve the chances for receiving adequate bids, and to evaluate whether bids represent fair market value. We made additional modifications to the program in response to the OTA recommendations. Regional Coal Teams have been given a larger role in recommending key decisions concerning the amounts of coal to be studied and the actual selection and scheduling of tracts for lease sale. These recommendations will be accepted unless the Secretary can cite an overriding national interest factor, or a governor's request to modify the recommendations. Smaller, more frequent sales will be held, to better judge market conditions and prevent over- or under-leasing. Public participation guidelines have been written, to document all opportunities for the public to comment at various stages in the planning process. We also decided that resource management plans prepared after the passage of FLPMA in 1976 must be completed, in order for a new round of lease sale planning to begin. The BLM will also beef up its procedures for consulting with affected Federal agencies during the planning process, to assure that the purposes and values of those agencies are considered and factored into land use decisions. To assure consistent use of an adequate data base in coal lease decision-making, Regional Coal Teams will develop standards and guidelines for data adequacy, and document the use of these standards. These procedures will also be applied to the unsuitability criteria screening process. Thus, the new leasing system announced by Secretary Hodel: is fully responsive to recommendations made by the Linowes Commission and the Office of Technology Assessment for improving environmental planning and fair market value procedures; gives the regional coal teams a major say in determining leasing levels, and on the timing,

Jan 1, 1986

BENEDICT SHUBART: I am rather surprised at one statement of Mr. McKeehan, that he found it satisfactory to bond only one track. It has always been my idea of good practice to bond both tracks and cross bond frequently, so that in case of any break in the bonding of one track, which frequently occurs, there will be no interruption in the circuit.

Jan 1, 1923

Jan 1, 2009

By C. P. Crawford

In the current issue of Link-Belt News is this quotation: "Advancing waves of other people's progress sweep over the unchanging man and wash him out." As we look over the industrial world today we are struck by the many waves which are sweeping over backward industries. Mergers are being consummated in all lines of endeavor. General Motors are making radios and the Bendix Brake Company are making airplanes. Railroads which twenty years ago were called to account by the Federal Government for their efforts to form combinations are today being ordered to combine. But what is of immediate concern to the coal industry is the fact that there is now in existence or in project a total of 3,641 miles of pipe lines to carry natural gas to most of the country's industrial centers. This is the wave of progress which is sweeping toward you and me. If we are to grasp the significance of these many changes, we must widen our vision so that we may learn some- thing from 'the other fellow's experience. The first lesson is that cost of production alone is not a measure of profit. It is an interesting fact that the production of an article represents a definite loss until that article has been sold for a price in excess of its total cost, and the money is in the hands of the producer. If this is true, then the selling price is more important than the production cost.

Jan 1, 1930

By Jason Laumb

Regional Energy Production ?Energy is a globally traded commodity and is influenced by regional and national needs as well as international trends. We can greatly expand energy export from the region. ?Significant opportunities exist for increased coal-based energy production.

Jan 1, 2006

will be held at COSMOPOLITAN HOTEL DENVER COLORADO June 3,4,5, 1931

Jan 1, 1930

By Wendy Hutchinson

Jan 1, 2007

By A. L. Jones

The subject assigned to me of "The Power" Problem of the Mine" is so broad that I have decided to confine myself to the question of the power supply itself, rather than the application of electricity throughout the property. We will look over certain economic aspects of the problem, particularly in the way it affects the mine manager or executive and his attitude toward the power plant. The accepted method of power application to the mine is by electric power, and the experience of each of you is that the job is never complete as you are always undertaking some further electrification which necessitates the stiffing up the power house to care for the additional load. The mine executive, then, is wrestling almost continuously with the problem of his power plant. Either it is overloaded and must be enlarged and rebuilt; or its operating costs are excessive; or it breaks down and limits coal output; or some one wants to sell new and improved machinery, until the manager almost hates the thought of such a restless part of his property. If he purchases power, every day new uses for it seems to be found. In many ways this unrest is due to short-sighted policy toward the problem, and the tendency when the problem of extension has to be met, to dispose of it in the cheapest way and without thought as to where the future is leading. The day when each opening had its own boiler plant, steam hoist, steam driven fans, steam pumps, steam loaders, etc., seems to be far behind us. The recognized method of power distribution today is by electric power, except for rather limited applications of compressed air; most of which is electrically compressed. During fifteen years contact with mines of Colorado and Wyoming the writer has seen nearly every mine power house double or triple in capacity or abandoned in favor of purchased power, worn. out and inefficient machinery thrown out, isolated boiler plants dropped, seam pumping at great depth changed to electric drive, all resulting in greatly reduced labor and fuel costs. Power costs, which in such isolated plants were considered normal, would be unthinkable today. One property where the main power supply was by compressed air from steam driven com¬pressors used under boilers 8.35 per cent of all the coal mined. The cost of power was 12 1/2 cents per ton of coal mined. Another property of four openings, each with its own boiler plant and usual equipment of hoists, pumps, etc., had a power cost of 10.3 cents for each ton mined; and these were days when you did not get very high prices for coal. Another property operating two mines mostly by steam used 11.1 per cent of the coal output under their own boilers and the power cost was 19.45 cents for each ton mined. Each of these properties is now electrified and power costs are from 3 to 4 cents per ton, and the fuel burned runs from 1 to 2 per cent of the output. With the broadening market and high prices for slack coal and the high prices for labor in boiler and engine rooms, the cost of steam is reaching a high figure, and efforts must be made to keep this down, by more efficient steam production and by utilizing this steam in better machinery which will increase the work done by each pound of steam. It must not be overlooked either, that the plant which is very wasteful of fuel is usually a pretty old one and one far from reliable. In a general way the more efficient the plant, the greater its reliability. Ample and reliable power supply means ability to get out coal when there is a market. The increasing use of purchased power is largely due to changing conditions which are tending constantly to push up the cost of power, unless the most efficient machinery is used and large scale production possible. The

Jan 1, 1923

By R. S. Morton

MR. CHAIRMAN AND GENTLEMEN: To be invited to address the members of The Rocky Mountain Coal Mining Institute on a particular subject is an honor I sincerely appreciate. The subject of this paper is, ?The Advantages of Having Such Men as the Fireboss Under State, Rather Than Corporation Jurisdiction." On the fireboss, primarily, depends the safety of the mine. When all the rest of the mine workers are still comfortably sleeping in the wee small hours of the morning the fireboss steals noiselessly away, from his bed to take up his daily task, a tour of inspection. He enters the mine, he inspects alone they workings that will be filled with men whose safety is in his keeping. Loyal to his fellow men and responsibilities of his position; he seeks for danger in every place, on every road and travelingway; going over caves, through dangerous places where none of the others are expected or allowed to go alone. How many of us give a thought to these dangers and the faithful work that this guardian performs for our safety. After the fireboss has made this round of inspection, he reports all the dangerous places to the foreman and enters them in the book; he is supposed to have performed his duties; he has no authority to enforce his recommendations. He has found a number of rooms that have not been timebered as they should be for the safety of the digger; he has told the diggers to they timber, up better for their own safety; he has kicked to the foreman about these same places. These conditions. continue until there is an accident. The fireboss reports, broken crossbars or bad roof on a roadway or some other danger to the foreman, but the foreman does not have it fixed, making, excuses, as he cannot put any one on that work today; or that it will stand until some idle day, and that is the way things go until the fireboss gets so he wonders what good he really is, is it any wonder it is hard to get good men to take this position of fireboss? The remainder of the shift the fireboss is used as a general roust-about, having to do such, work as building stoppings, help the timberman or track layers, pull rails out of danger in pillars, a trapper is off and he is told to trap that day, when the mine is idle he is laid off to cut expenses. That is the way the fireboss is treated. The fireboss is not merely a merely a necessity to be lightly regarded but a factor whose authority should be unquestioned. The fireboss has made his district and knows just what conditions the workings are in, and sees lots of dangers that the foreman does not. In the morn-

Jan 1, 1921

By D. Harrington

E. H. DENNY (United States Bureau of Mines, Denver, Colorado) In the absence of Mr. Harrington it is my privilege to read his paper, which is in his usual, forcible and sincere style, and it is within the province of this Institute, certainly, to go into it as it concerns safety and efficiency in mining. He brings out some points in his paper that, I think, are well worth the consideration of the Institute. The figures he uses were compiled by Mr. Adams, of the Bureau, and cover a five-year period. However, examination of similar Bureau figures for a ten-year period, or any other long period on other bases brings out similar results. The figures in this paper have been based on the million hours of exposure of accidents, and the figures based on three hundred working-man-day basis, or on tonnage, brings out similar results. This paper is entitled "Accident Record in Western Mines," and it is, in a way, an amplification of Mr. Harrington's letter which was read at the Glenwood Springs Meeting.

Jan 1, 1927

By Samuel Tescher

The operation of gaseous mines is a problem, due to the fact that we have not only the ordinary mine accidents to guard against, but have also the ever present menace of a mine disaster involving a large number of human lives, and the destruction of valuable property. In looking over the reports of mine disasters throughout the country in the past several years, we find that methane gas, coming in contact with an ignition agency of some kind, has been the source of at least 75 per cent of our mine explosions. Coal dust, of course, plays its part in propagating the explosive action throughout the mine workings and rendering it more violent and destructive; nevertheless, the initial ignition of a body of explosive gas-sometimes of very small volume-has been the primer for the large majority of our mine disasters. We find also, that the places of initial ignition are most frequently found at the working faces, or in close proximity thereto. This is mainly due to the following reasons: First-The working faces are, as a rule, the places where methane gas is most freely generated. Second: They are places that are most poorly ventilated. Third-They are the places where ignition agencies are most frequently found. The sources of ignition, as a rule, consist of naked lights, the shooting -of shots, defective flame safety lamps, and electrical arcs. The problem, then, in the operation of gaseous mines, is primarily to so ventilate the working faces that an explosive mixture is not likely to occur, and to endeavor to keep away from the working faces all sources of ignition. To do both of these things may seem impossible. Nevertheless, by working along both of these directions, a great many disasters can be avoided. The efficient ventilation of the working faces is paramount. By efficient ventilation, we mean the continuous passing of large volumes of air at the working faces. This can only be accomplished by adequate ventilating equipment, capable of being driven by at least two independent and distinct sources of power, together with large, clean, straight air courses which are free of short turns, constructed areas, and leaky doors and stoppings. In other words, furnish a suitable course for its travel through the mine. Many of us sharpen our pencils and rack our brains to properly estimate the proper size pump and pipe equipment that may be needed to handle a certain amount of water. We estimate the size of copper conductors to a nicety. We immediately rush to repair leaks in our water, compressed air or electric lines. But how many of us give serious thought to the travel of the air through our mines, the health and safety-giving fluid on which so much depends! In driving air courses, a certain economical cross-sectional area should be adopted and maintained as standard. When turns are necessary, they should be made with long radius curves, and the cross-sectional area should be increased on the curves. All entry stoppings should preferably be built of monolithic concrete, with suitable hitches into floor and ribs, and after the concrete has set, they should be examined and leaks due to shrinkage and settling should be eliminated. Overcasts and their approaches should have cross-sectional areas larger than the entries leading to them, to allow for the sudden change of direction, bearing in mind that air wants to travel in straight lines. In the early development of a property, ample provision should be made in the size of the main entry pillars to allow for the driving of additional

Jan 1, 1925