Search Documents

By William Perry Pendley

Let us go back in time, back to when a Navy veteran from the South was President of the United States, a man from the Rocky Mountain West was Secretary of the Interior and a leading environmentalist was head of the EPA; and there followed what many perceived of as a war on the West-on our water, on our timber, on our oil and gas and mineral exploration, and on our small communities. It's easy to think that I'm talking about the administration of James Earl Carter, III of Georgia, but I'm not. I'm talking about this administration, the administration of George Herman Walker Bush of Texas. I say that as a life-long Republican who never voted for a Democrat and who worked hard to put George Bush in the Oval Office. Many of us wondered, in 1988, what Vice President George Bush meant when he said; "I am an environmentalist." Well, now we know. In his State of the Union address, which was otherwise lacking in specific detail, George Bush said two very specific

Jan 1, 1990

The twenty-fifth regular meeting of the Rocky Mountain Coal Mining Institute was called to order at 11 a. m. Monday, August 29, 1927, in the County Court House at Trinidad, Colorado, the Vice-President, F. L. Peart, presiding. After a few words from John F. Carmody, Editor of Goal Age, J. Q. McNatt, Division Engineer of the Colorado Fuel & Iron Company, read a paper on "Coal Geology." In the afternoon, Prof. C. B. Carpenter, of the Colorado School of Mines talked on the work in Fuel Engineering being developed at the Colorado School of Mines. W. C. Holman, of the Phelps Dodge Corporation, then read his paper on "Developing a Pit Car Design." L. M. Kuhns, Safety Engineer of the Gallup American Coal Company, read his paper on "Safety Methods at Gallup American No. 5 Mine." After discussion the meeting adjourned for the day.

Jan 1, 1927

PRESIDENT LITTLEJOHN: Before we open the discussion on the Utah mining laws, I want to bring out what I consider a slight misunderstanding on some of the things that I said this forenoon relative to our comparison of accidents. I did not mean to infer that we, as mine officials, are satisfied we have done the best we can to eliminate the accidents, when I was talking about a four-to- one comparison. I do not want any- one to get the idea in their heads that I do not think we are doing all we can. There is not any of us who can state that, even if we better these figures. It is the general understanding that these figures are based upon ratios per thousand man shifts and not upon the tonnage basis that we use. If it were based upon a tonnage basis, I think the figures would be pretty nearly reversed, for we are producing from two to four tons more per man than they do in Great Britain. The discussion will now be continued as I said this morning. There is a gentleman in the audience here that is as guilty of making these laws as I was, and I am quite sure when speaking he will confine himself to the subject of Utah Mining Laws and the prospective results. Before Mr. Monay starts with his paper, I want it understood that this discussion must be finished by 2:30 for the reason that we have still quite a lot of business before us this afternoon.

Jan 1, 1925

T. T. READ, BUREAU OF MINES: Mr. McAuliffe has asked a very practical question. Expressed in another way, the question is: If we have decided to use rock dust to prevent coal dust from exploding, have we got to take rock, that is, solid material,, break it up and finally grind it into dust (and fine grinding is very expensive), or can we take material that is already in a pretty fine state of subdivision and thereby save the expense of pulverizing it? Most of the preceding discussion has been from the view-point of practical experience, and I should like to suggest that we have not had enough practical experience in rock dusting to be able to answer this question, from the viewpoint of experience, with the degree of definiteness that Mr. McAuliffe desires. With your permission I will discuss the matter briefly from the theoretical standpoint, because after all the theoretical considerations, insofar as we understand them correctly, will apply to every' case, whereas in coming to a decision on this matter it will be necessary to take into consideration local conditions, which will necessarily vary in every case. Considering the matter in a rather elementary way, the first point is: What makes coal dust explode? The air of this room is full of dust at the present moment, even though we do not notice it. If you were to close up the room for a week, enough dust would settle on the floor so you could write your name on it. Of course, the dust which is in the air of this room is not coal dust but even if it were coal dust and you were to bring an open light in' here we all know that the dust would not explode. The reason for that is that the dust particles are not close enough together for the flame to propagate itself from one to the next. You will probably be able to see in the demonstration in the gallery on Saturday that the coal dust explosion is practically a very rapid burning of the dust. When you light one piece of dust it burns and gives out heat and if there is another piece of dust close enough to it so that the heat from the first piece is able to bring a second piece up to the burning temperature, then the flame will propagate itself through the mixture. But, if the particles are so far apart in the air that the' heat from one particle is dissipated before it reaches an adjoining one, and is therefore not able to bring the second particle up to the burning temperature, then the flame will not propagate. To get a coal dust explosion, it is not sufficient to have coal dust suspended in the air. The coal dust particles must be close enough together in the air so that the heat from one burning particle is able to heat the adjoining particles up to the point at which they will burn. There has been some discussion of the size of dust particles that will cause an explosion to propagate, and it has been pointed out that the minus 200-mesh dust is the most dangerous, and that particles coarser than 20-mesh will not propagate an explosion. There are two reasons for that. A large particle has very much smaller surface in proportion to its weight than a small particle has. You know the old story about the Indian who when asked how he could go around in cold weather without any clothes on said that an Indian was all face. A 200-mesh particle is almost all surface and there= fore is able to burn almost instantaneously, which means that it gives out its heat almost instantaneously, whereas a large particle with less surface in proportion to its weight burns more slowly, gives out its heat more slowly, and the heat has more time to be dissipated. The second reason why coarse dust does not easily propagate a flame is because it is so hard to make it

Jan 1, 1924

Mr. Geo. B. Pryde, Chairman; Committee on Safety, Rocky Mountain Coal Mining Institute, Rock Springs, Wyoming. Dear Mr. Pryde: In accordance with suggestion in your letter to me of June 21, 1923, Mr. Roberts, Mr. Dalrymple and I had a meeting and attached find our contribution to the proposed August report of the Committee on Safety. You will note that we have confined ourselves to matters in connection with explosions and prevention of explosions, in coal mines. If the committee is to report on general safety in coal mines, including accidents from haulage, timbering, rock falls, electricity, etc., we would like to suggest that you ask other members of the committee to specialize on one or more of these subjects. Especially we believe it would be advisable to specialize as to precautions against electrical accidents with giving of data as to maximum voltage, precautions to be taken as to gas ignitions by mining machines at faces, best methods of placing power wires underground, etc.; also give information as to up-to-date safety installations, such as whistle devices notifying of disarrangement of ventilation or devices for quick cutting off of electrical power from mines under certain conditions; also give data as to efficient safety man cars on various pitches, etc. Yours truly, D. HARRINGTON.

Jan 1, 1923

By D. J. Griffiths

Beyond doubt it is practically impossible to eliminate all chances of accidents from falls. Mother Earth is not going to give up her treasures without some sacrificing on our part. This particular question ranks among the important subjects connected with coal-mining, and has been given less attention as a factor of life- and limb-destroyer than any other cause. The single fatalities which happen create very little attention; nevertheless, when counted up at the end of the year, they outnumber the unfortunate ones that are mowed down by the wholesale by mine explosions. Fire-damp and coal dust were often considered the greatest evils in coal-mining. All records, however, prove this conclusion to be wrong. The second annual report of the Bureau of Mines gives the loss of life caused by falls of coal and roof in 1910 as 1,310, and in 1911 as 1,321. The reports of Pennsylvania mine inspectors for a period of thirty-three years show that 59.38 per cent of all the accidents underground were caused by falls of roof and coal. Also, the Bureau of Mines shows in its last issue on fatalities that accidents from fall of roof and coal killed more men than any other two causes combined, and that they account for more than half of the deaths under- ground. It seems we are getting too accustomed, taking too many things for granted, running too many risks, trusting too much for the best, and preparing too little for the worst. We must remove the cause; then the effects will cease. However, I can see that a better day is here. The main damaging factors underground are falls of roof and sides. A bad roof is tender and lacks the adhesive qualities to sustain its own weight over comparatively small areas. A roof of any character which is frequently penetrated by well-defined slips and cleats, is characterized as a treacherous roof. The carelessness of men has been one of the main causes of most of the accidents in mining as well as in any other industries. Three Grades of Miners Miners can be classified into three distinct grades, to-wit: the experienced and careful, the experienced and reckless, and the inexperienced. The accidents which the first class usually meet with occur through the carelessness of their co-workers, as well as through accidents which are termed unforeseen, such as falling roof between timbers, and between the timbers and the face of the coal. This may have 'previously given evidence of being absolutely sound and safe, but be released by invisible slips or by sudden outburst of occluded gases in large quantities, as we term big blowers or feeders,

Jan 1, 1913

By David Scrymgeour

All low cost coal has been mined. Engineers are searching for a safe and effective way to mine coal seams' deep within the earth. The most modern of these is the RL, an acronym for Robotic Labor. Mining robots are programmed to do specific jobs but can think on their own during an emergency. MR's, or mining robots, usually have a same basic shape. A torso is mounted on treads. Designers chose treads because it gives the robot a great deal of mobility. The torso has two arms. One arm is equipped with a human hand. The other has a human-like hand. Mining is done underground. A small robot goes around punching holes in the coal. A small charge is inserted in the hole. The MR ignites the charge with his laser. It explodes after three minutes. The MR returns to the station where his battery is recharged. Mobile cement barricades are moved between the blasting area and other working MR's. After the charge explodes the barricades are moved to another area. The MR returns and cuts the coal chunks into pieces. Another robot comes and loads the coal and carries it to the loading bin. From there it is taken to the surface where it is weighed and shipped. The whole process was done by robots. Humans just supervise but help in an emergency or malfunction.

Jan 1, 1987

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

PRESIDENT LITTLEJOHN: I have every reason to know Mr. Pryde was carrying out some experiment a while ago in some of his mines. He and I had a little correspondence on the question, and I think he may have a word or two to say about it. He has not been on his feet today at all. I will ask Mr. Pryde to tell us what he has to say. MR. PRYDE: I have not very much to say about shooting coal with permissible powder as far as slack is concerned because we are not in the commercial business. All of our coal goes to the railroad and a very large part of it is crushed for use in the stokers of the locomotives. We are on a 100 per cent permissible powder basis and as far as I am able to see, I do not believe that the percentage of slack is increasing with its use. We find it hard to convince our commercial neighbors of this fact because they are naturally very much against increasing their percentage of slack on ac- count of the low price received for this grade of coal. I, personally, believe that where a change is made from black powder to permissible powder the percentage of slack will be increased for a time because the miners have been accustomed to using black powder and they are rather suspicious about going to the permissible powder and I do not believe that we can blame them very much. So the tendency with them is to use too much powder. We have gradually overcome this, although, as I said before, we have not kept close track of the production of slack. However, we try to get as large an amount of lump coal as possible. Broadly speaking, I can say from observation that in my opinion there is very little difference in the percentage of slack with the use of the permissible powder that we have today than there was with the use of black powder. I also get this information from our mine superintendents. Mr. Peterson and the other explosive men have been very helpful to us in the use of permissible powder and I confess I have to take everything back that I said several years ago. At that time I was against permissible powder, particularly on account of the cost, but, with the newer permissible powder, we have gotten the cost down very well. I know today that the cost of permissible powder in the coal mines of the Union Pacific Coal Company is less than when we were using black powder. I know this because of the fact that we kept a record of the number of tons we got with black powder, and the number of tons we get with permissible powder compares very favorably in cost. I know this, too, because of the fact that our employes, except in the first few weeks of using permissible powder, have made no demand upon us for any in- crease ill pay to offset any added cost that might accrue in the use of permissible powder and the fact that they have asked for no increase is very conclusive proof to me that it is not

Jan 1, 1925

Mr. Shepard's paper was unfortunately delivered extemperaneously so no record is at hand. He spoke most interestingly and at length on the oil shales of Colorado, giving his opinion as to the ultimate outcome of the oil shale industry. He explained his idea that it would be built up of comparatively small plants, each of which would make the crudes, or more exactly would roughly divide the crude into its fractions, piping or shipping the fractions to a Central Refinery, using the residue for fertilizer, as it runs very high in fertilizer salts. He recommended that this plan be taken up by Coal Producers, that they consider the possibility of breaking up coal and selling its more refined products in place of selling raw coal. He spoke at length of the various outlets for products of distillation. Mr. McDermott gave a very interesting talk later on work that is being done in the Northern Colorado field along these lines. Mr. McDermott mentioned the strange fact that coaly materials such as mother of coal appeared to give just as good or better results under distillation than did lignite coal. Messrs. Randall, Howe, Goddard, Danford, and Nash added interesting data covering the use of pulverized fuel, and this data will be collected and offered to the Institute later in the form of a paper. Mr. Young spoke of the use of powdered coal in small units for small plants, mentioning the system now being offered by an Eastern Iron Works for small heating plants.

Jan 1, 1922

By Parley Potter

GENTLEMEN OF THE COAL MINTING INSTITUTE: I was requested to write an article on mining a short time ago; however, the time has been so short that I have not had time to prepare an article as I would like to have presented it to this body. In writing this article it has not been my intention in making comparison of various mines, to favor one or discredit the other. I hope it will be considered in that light. The coal mining industry as I have seen it in the past, at present and in the future. In years gone by large tracts of coal land could be obtained at a very small cost, and as yet coal land may be purchased at a reasonable price in this country, but I believe the time is near at hand when the methods of mining will have to be changed greatly in this country. Many changes have taken place-in the last few years, some of them have been forced by law, others by the coal operators themselves, after being convinced that the changes made were for their own benefit. During my 20 years in the mines I have seen thousands and thousands of tons of coal lost that could have been saved if proper methods of mining had been used. The Room and Pillar system of mining coal is none. too good at its best ; a certain per cent of the coal is always lost, yet it is about the only system that can be used under certain conditions, but where the Longwall system can be used I believe it is the best system yet introduced. If the Longwall system is used' there is no coal lost. You get it all as you advance with the workings. Some coal operators object to the Longwall system for several reasons, and most of the reasons they advance are not founded on facts. For instance some of them claim it is too expensive. I will admit that the cost per ton is a little higher in Longwall than it is in Room and Pillar as a rule for the amount of coal' mined, but after the Room and Pillar mine is finished as a rule there are thousands of tons of good coal lost, for the simple reason that it cannot be mined at a profit. In many cases if the same mine had been operated on the Longwall system every ton of saleable coal could have been mined at a fair profit, and in the long run would have netted the owner much more money than it did under the Room and Pillar system. The Longwall system has been in operation many years in Europe and especially Great Britain, and is the most approved of systems in many countries at the present time. Millions of tons of coal have been saved by its use in those countries. It is claimed that the Armour Packing Company loses nothing but the squeal of the hog when it is killed, and doesn't allow it to squeal much. Why lose coal if the Longwall system of mining will save it? The Longwall mine is far more easy to ventilate than the Room and Pillar mine; the air has a much less distance to travel for the same amount of working face in Longwall than it has in the Room and Pillar.

Jan 1, 1921

PRESIDENT WHITESIDE: The chair will now throw the meeting open to discussion. GEO. B. PRYDE: In the old days at Rock Springs we had electric plants situated about half a mile from our mines; we had small boiler plants; we had an electric plant with about 600 kilowatt capacity. About ten years ago we discarded the old steam plants and started building towards a centralized power plant. We now have three 2,500-kilowatt turbine generators and one 1,000, and our peak load is about 7,000 kilowatts. We have had to rebuild the old power plant, scrap the old machines, and install water tube boilers. We did this as a matter of economy in a small local plant we had years ago, and it has grown to be a large central plant, supplying power for about 20,000 tons of coal daily, and distributing this power within a radius of twenty miles. We have found this method of power to be more economical than with the old plants, and the people who buy power from us in the Rock Springs field say it has been to their advantage also. We found this last year, when we had to shut down for five months, that that plant was the only plant operating in the Rock Springs field, supplying all the power, running of fans and pumping during the time the mines were shut down, and it helped the situation very much. We had an old wooden building which we had to tear down, raise the walls, and put on a steel roof; had to rebuild the boiler room and rebuild the boilers. The water situation at Rock Springs has never been very good; we get our water from wells 250 to 500 feet deep, and use one and one-quarter million gallons a week. We have two large spray ponds and we have gotten along well. There isn't any comparison between the central power station and the old method of making power. (Applause.) FRANK YOUNG: I listened with a great deal of pleasure to the paper just read, and it struck me it was remarkable how a paper prepared by anyone could be so nearly identical and coincide so very near with the experience of another. It is just like some work I have had. I had the engineering part to do for the power plant for ten years, and I think at that time we did all of the things that he mentioned in his paper. Also his analysis of the cost of power seems to me exactly right. If I had gathered the figures and made the statement myself I think it would have been very much the same as was read. The recommendation that it is better to buy

Jan 1, 1923

By J. F. McDermott

The problem of converting our raw coal, and especially those coals that are not suited for long storage, in other words soft, into a fuel which would be at once clean; of a high B. t, u. content and low ash, is one that has occupied the minds of many able chemical engineers and hydrocarbon technologists during the past few years. Low temperature carbonization is the present outcome of this line of research, and many methods have been evolved of recent years to turn out a serviceable, useful fuel, and at the same time, save the by-products. As most of the research and data within my experience and knowledge pertains to lignite or sub-bituminous coals, I will confine my remarks to coals of that character and grade: I might say that Colorado coals, commonly called lignite, are not in reality true lignite, but are sub-bituminous, although I have in my possession an analysis of a Colorado coal which shows a moisture of 17 per cent, volatile 31.5 per cent, fixed carbon 28.8 per cent, and an ash of 22.7 per cent, and B. t. u. less than 8,000. Even this, though useless for domestic or indeed industrial purposes, could not be classified as true lignite. However, for the purposes of this paper I will refer to these coals as lignite. Two thousand pounds, or one ton, of raw lignite carries about 20 per cent moisture. This, of course, varies in some coals, but is, I believe, a fair average. For carbonization purposes this is usually dried to a 5 per cent moisture, therefore leaving but 1,700 pounds of coal to be placed in the retort. From present knowledge, and with the average process of carbonization, 70 per cent of this coal will come out carbonized, or 1,190 pounds, to which is added about 10 per cent pitch, which is fried out as the coal passes through the retort, and which is used as a binder, making a total of 1,360 pounds of coke or carbonized coal. This is usually in appearance a dark colored, rather porous coke of about the size of pea coal. It burns without smoke and have a very high B. t. u. content. According to most authorities on this subject, carbon, hydrogen, oxygen, nitrogen, sulphur and ash constitute the only elements on which carbonization value of a coal depends, and of these hydrogen is the most important. It is claimed the value of a coal for carbonization purposes may be roughly surmised from the hydrogen content. If this is promising, that is, showing an available hydrogen content of from 3 to 5 per cent, the coal should be given a careful ultimate analysis. Should the seam, as often happens in lignite coals, show varying bands of coal of different structure or appearance, samples should be taken from each band as well as a gross sample taken down the face of the seam in the usual way. This is in order to determine what part of the seam is most promising for by-product processes. A seam showing a high nitrogen content adds to the attractiveness of the coal in carbonizing as; if available nitrogen is 2 per cent or better, it should give a very high ammonia yield.

Jan 1, 1923

James Westfield, Assistant Director, United States Bureau of Mines, Washing- ton, D. C., called the second morning session of the Rocky Mountain Coal Mining Institute to order, and promptly introduced John Peperakis, Manager of the Sunnyside Operations, Kaiser Steel Corporation. Sunnyside, Utah, who spoke on "Ground Control Developments, Sunnyside Mines, Kaiser Steel Corporation." Mr. Peperakis illustrated his talk with a number of slides which were not reproduced with the printed text. (For the printed text of Mr. Peperakis' paper see index.) James J. Diamanti, President of the Car- bon Fuel Company, Helper, Utah, was introduced by Mr. Westfield, and he spoke on "Small Mine Operators Help Themselves." Questions from the floor followed Mr. Diamanti's talk.

Jan 1, 1961

Albert M. Keenan, President, Thompson Creek Coal and Coke Corporation, Denver, Colorado, opened the third session of the Fifty-ninth Regular Meeting of the Rocky Mountain Coal Mining Institute at 9:30 a.m., and introduced the first speaker of the morning. Raphael J. Moses, Attorney, Colorado Water Conservation Board, Boulder, Colorado, spoke on "The Opportunity for Coal in Colorado River Basin Development." (For the printed text of Mr. Moses' paper see index.) Stephen F. Dunn, President, National Coal Association, Washington, D. C., was introduced by Mr. Keenan, and he addressed the Institute concerning "Coal and the Washington Scene."

Jan 1, 1963

By Franklin P. Wood

Unnumbered ages have passed since the time when nature's laboratories were working without the aid of capital or labor unions assisted only by earth's cooling crust and old Sol's rays, to lay the prodigious coal beds of the earth and distil the oils which now furnish the basis for the world's great industries. Strangely enough rays from the same old sun probably somewhat diminished in intensity are still drawing from earth to clouds the water that will run down hill and through man-made devices produce energy to compete with that made with the products created in ages past. So now we find that within the past century vast human industries have grown up around the products of these agencies and here we are today discussing the many problems connected therewith and among the others the subject of this paper, which is essentially the relation of COAL to OIL in industry. The problems involved are those of human relationship and are not fundamentally unsolvable when engineering skill and knowledge is properly applied. The last few years has developed a brand of pessimism that is especially prevalent in the coal industry, at any rate in the west where we come in contact with it. In any general discussion with coal men, a very short time only is required to bring out the feeling or expression that the coal business is on the rocks and the reasons run the gamut of human deviltry. We have heard that in the not far distant past corn was so cheap that the farmers were compelled to burn it and thus deprive the coal mines of their well earned right to sell coal for this purpose. We have heard that the flood of oil is so vast that it was being burned in preference to coal, and to heap insult on injury that the rail- road locomotives were burning oil in order to pull coal away from the mines. We have heard that the union was responsible for all the woes to which the industry is subjected. We have heard that the family tin lizzie is so depleting the family exchequer that coal could not be purchased and if purchased could not be collected for. We have heard that producing mines are so numerous that the profits are a negligible quantity. These are but a few of the reasons assigned for making the coal producers a class of pessimists which is not good for the industry. All these reasons given and all the others must be taken collectively and these are not the cause but the effect of a rapidly changing civilization. An analogy may be found in the experience of many of us in the electric industry a few years ago. You may remember that less than 20 years ago the high efficiency Tungsten electric globe was introduced. It was so much more efficient than the old carbon lamp that only one-third of the current previously required was needed to produce the same illumination. Consternation seized the ranks of electrical men who had little or no vision, for the out- look was that so little current would be sold that everyone would be bankrupt. This limited vision, however, did not prevail, for all engaged in the industry spurred on by necessity, accomplished many of the things that we are now enjoying the fruits of be- cause the electric industry has grown and is growing by leaps and bounds and every highly efficient improvement is greeted with rejoicing. It is well known that when the old type of carbon arc lamp began to be replaced by modern units the manufacturer of carbon rods thought his doom was sealed and yet these same manufacturers have so adjusted them- selves to conditions that the dry battery business of today is of vastly greater volume and profit than was the carbon rod business of the past. Of course, there are industries that should not have survived anyway that have gone down and out to makeway for vastly improved conditions and can

Jan 1, 1925

By T. H. Butler

February 22nd, 1926. Mr. Benedict Shubart, 521 Boston Building, Denver, Colorado. Dear Mr. Shubart: At your request, am submitting to you several suggestions for the amendment of our safety code which you felt should be kept up to date. As before, am advising you that these suggestions do not have the approval of the entire Safety Committee, but rather are the individual opinions of several members who have expressed their wishes in the form of letters to me. I am particularly indebted to Mr. Dan Harrington and Mr. Wm. Littlejohn for their assistance. Would recommend the following amendment a to the various sections. Section 1. Wherever possible trolley wires should be securely hung to roof or timbers at a distance of not less than five feet and not more than six and one-half feet above rail and six inches to one side. Spacing of hangers should be from 20 to 25 feet apart. Section 2. 500 volts D. C. should not be allowed in any installations. Trolley wires should not carry a voltage of more than 250 D. C. Pumps, mining machines and other small machinery units where A. C. power is used should not carry a voltage of more than 220. Large units, such as pumps, motor genera- tor set and hoists, may use a voltage of 2,200. When power cables to operate same are of armored construction, cables should be securely buried at all crossings. Section 4. Where power lines pass through door frames or stoppings they should be properly insulated with porcelain or rubber tubing. Whenever men get on or off man-trips in vicinity of trolley wires same

Jan 1, 1926

MR. MARGOLF: Thank you very, very much Harris. There's sure a lot there to think about in terms, of our image, particularly. I think we should keep' in mind what Harris said about our history not being monolithic. Therefore our image can only be that, which is reflecting the weakest link in our industry and I think that's a burden on all of us. Perhaps to do some policing amongst ourselves to try to improve whatever might be our weakest link and thereby elevate our entire industry. Our third speaker this afternoon is another good friend of mine of long standing and I am very pleased to be able to introduce to the Rocky Mountain Coal Mining Institute Bob Golten. Bob is a graduate of the University of Michigan with a degree in Economics and Harvard Law School. His professional experience encompasses private practice in Chicago where he was born and in the federal government as a public defender in Washington, D.C. and in the Department of Justice as a tax , attorney. Some of us have come to know Bob more in his present role as the senior counsel for the I National Wildlife Federation. He's also Adjoint Professor of Law and Director of the National Wildlife Federation Resource Clinic, University of Colorado. Boulder campus. In addition, Bob has served with the Rocky Mountain Center on Environment as one of its directors for a number of years. He's very active in a number of areas that are not only civic but he does reflect what I would present by way of introduction as a perspective

Jan 1, 1982

By J. J. Welch

The thought and practices in the field of accounting in the past two or three years are undergoing far-reaching changes, but more important than this is the changing viewpoint of business managers toward accounting reports and statistics. Accounting is no longer considered a necessary burden of business, for progressive managers and operating officials everywhere look upon it as a service. A service of supplying operating men and executives with information on their affairs which enables closer and more effective supervision, to the end that business may be conducted more satisfactorily and more profitably. This service is the real function of accounting in business management. Of the many treatises on accounting published in recent years, the great majority deal with principles and procedures, and were written purely from the accountant's point of view, thus they appeal, and are of interest, chiefly to accountants. Recently, however, the interest displayed by the operating man, be he president, general manager, superintendent, mine foreman or potential mine executive, calls upon the accounting department to serve him in furnishing him with figures showing the financial position and economic progress daily. In order to effectively render this service the necessary co-operation between management, operating and accounting -forces must exist. Satisfactory services may be developed only on a basis of close contact and pulling together between these departments. It is not a one-man job, the responsibilities necessarily rest on all. This co-operation contemplates:

Jan 1, 1932

By F. T. Baker

The Primero mine, operated by the Colorado Fuel & Iron Company, is located 17 miles west of Trinidad, Colorado, in Las Animas County. Unusually bad roof conditions, along with heavy side pressure and other conditions causing rapid decay of timbers, all combine to create a very serious timbering problem. The height of the coal averages six feet six inches. It is a heavy coking coal and has a tendency to become easily crushed and broken down in the seam. The seam lies about 35 feet below the sandstone and the intervening formation is composed of loose shaly rock, and as the coal is extracted, the air slackens this rock to such an extent that within 24 hours, roof falls varying from five to fifteen feet in height are likely to occur. Under these conditions it is necessary to use cross bar sets in both rooms and entries, and they must be spaced no further apart than three and one-half foot centers, and be maintained within a distance of three feet of the face. Rooms are spaced on fifty footcenters, and cannot with safety be driven to exceed 14 feet in width, and 200 feet in length. The large pillar must be maintained to protect from side pressure, and the rooms must be driven up and retreated with as quickly as possible to avoid the squeeze caused by the intense side and roof pressure. Best results in extraction have been obtained by driving rooms for only a distance of 150 feet. Under these circumstances, it is readily seen that timbers of small diameters cannot be utilized in timbering any development work of a permanent nature. Entries are driven nine feet wide, and special peeled piling with an average diameter of 12 inches are most commonly used. It, is necessary to use lagging between each set of crossbars . Conditions such as these necessitated an immense expenditure for mine timber. In addition to ordinary seven and eight foot props, we used a yearly average of 65,000 feet of heavy peeled piling, averaging in diameter from 10 inches to 12 inches. Annual expenditures for timber of all classes was in excess of $60,000.00. Timber costs per ton averaged around 29 cents. In view of these exceptionally severe timber conditions at Primero, the company, in 1920, had a survey made with a view of providing some remedy to this problem. A comparison of the life of main entry timber at other bituminous mines was made, and an average life of four years was established. The actual data collected at Primero indicated an average of less than two years in the manway or "return" airways, and up to five years on the haulageways or "intake" airways. While some of this timber will stand up for a much longer period than this, a close inspection will reveal in most cases that its period of usefulness is spent. It is very essential when discussing the life of timber, especially that used on, main haulageways and aircourses, that a distinction be made between the point of service, that is, the point where it is sound, serviceable and able to carry weight, and the point of breakdown or failure, where it is no longer sound and able to carry weight. In figuring the life of timber, the point of service only should be considered as timber will frequently stand for a considerable length of time when it is entirely decayed and unserviceable. The larger part of the timber used for our permanent work was Alpine Fir, or what is locally termed Red Spruce, and the supply of this I is gradually becoming depleted and has to be obtained at a point so distant

Jan 1, 1926