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Article I1 of the RMCMI Bylaws reads: Section 1. Classes. The membership of the corporation shall be divided into three classs, consisting of active members, life members and senior members, who shall have such rights, privileges and qualifications as these bylaws may provide. The names of all active, life and senior members, together with current mailing addresses, follow. [Lt. Jay Abbott M. L. FOSS Co. 7458 S Jackson St Littleton. CO 80122 Lt. Ronald H. Achziger Midwest Rbr & Sply Co 6404 E 39th Are Denver, CO 80207 ]

Jan 1, 1986

By Richard M. Whiting

Thank you very much for that introduction. I spent part of my early career in the coal industry here in Colorado, and I am always happy to return. In such a beautiful setting, it seems out of place to talk about "Improving the Climate". But in our work-a-day worlds, we know the climate for the coal industry is something less than picture perfect. But unlike Mother Nature's climate, there are some things we can do about the climate for coal. Today, I want to talk to you about sonic of the activities that we are engaged in... and that you can support... to improve that climate. A number of challenges and opportunities face our industry. I will try to set the stage for this conference by briefly describing the current climate for coal - which is indeed very challenging. I will then outline some of the steps we are taking to broaden our base to include our allies in the rail and electricity industries and the public at large.

Jan 1, 2000

By T. H. Brien, O&apos

At nearly all of the copper smelters in the Southwest, at some time, calculations have been made having in view the economy of replacing fuel oil with pulverized coal as a heat-producing medium for smelting operations This matter has been, and is more so now than at any time heretofore, of very great importance. Due to the intensive development of oil-producing areas of the world and the tremendous use of fuel oil for many purposes, it seems that before many years the supply of oil will become so small as to prohibit its use for such operations as smelting. This may be caused by prohibitive prices, or even by government decree as a conservation measure. In the event that the use of fuel oil becomes out of the question, the copper companies have just two alternatives: the use of pulverized coal or electricity. The copper companies of the Southwest produced an average of 808,400,000 pounds of copper per year for the war years of 1916, 1917 and 1918. This figure is, of course, a higher one than has prevailed since the war, but at the present time nearly all of the mines and smelters are getting back to capacity. There is no doubt whatever that the consumption of copper is going to increase, perhaps for the next ten years. This means that more copper mines will be discovered and developed, and that the mines which are now producing will be called upon for a greater production. This all tends to show that the mine manager who is looking ahead must develop some substitute for fuel oil in the event of its use becoming prohibitive, and all indications seem to point in that direction. The only coal which is commercially available to the smelters in the district under discussion must come from Colorado and New Mexico. These coals are high in ash and volatile matter and comparatively low in calorific value. The proximity of the smelter to the coal mines is a large factor in determining which fuel is more economical. Most of the smelters within two or three hundred miles of the coal mines find it more profitable to burn coal, while those at greater distance find that the higher freight charges on the coal make the use of oil more economical.

Jan 1, 1923

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 Vincent R. Bovino

The future of coal mining is bright - only if we realize and then manage as though we are competing in the world marketplace. Accept it or not, our market is global. We tend to think our problems are caused by the uncontrolled foreign production of coal, and the uncontrolled drop in coal prices. I submit that our problem is not the world pricing structure - part of our problem is our on-site cost structure - our productivity. We are the world's best at getting out the tons - that is, production. Most mine managers thrive on that. What is in serious doubt is our productivity - our ability to produce tons of coal in a cost effective manner. Please think about the difference: ? Production is tons of coal. ? Producitivity is decreasing the cost per ton of coal. Our future is bright, only if we can increase our productivity by trying different and new ways to manage our businesses and our people. Unlike the easy successes during the 60's and 70's, success in the decades ahead will depend on our ability to achieve greater levels of productivity. If mining and other old line smoke stack industries are experiencing difficult times in 1986, three years into an economic recovery, what will happen when the economy cycles downward? Any operation can achieve unlimited productivity by developing the resources within their employees. As an industry, we have harvested the

Jan 1, 1986

By Circadian Technologies

Alertness levels naturally fluctuate during the day and night Basic functions ??digestion, body temperature ? follow predictable 24-hour patterns Adjustment to night work creates health challenges for shiftworkers Performance decreases during overnight and post-lunch dip hours Fatigue supercedes training & experience Fatigue is a major cause of human error

Jan 1, 2010

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. C. Foote

MR. FOOTE: This paper deals with blasting and mechanical loading. The Union Pacific Coal Company does all of its blasting with permissible powder and electric shooting, but this paper deals principally with blasting in connection with mechanical loading. With the introduction of mechanical loading into the coal fields of southern Wyoming one of the main problems to be taken into consideration was the drilling and blasting of the coal. The methods used in blasting coal for hand loading were found to be ill adapted to the mechanical practice, so numerous tests were conducted from time to time to determine a system or systems whereby the coal might be blasted in a form to be easily handled by the loading units. The general practice in blasting coal for hand loading, for example in a room 24 feet wide and seven feet high with an undercut of seven feet, would be to shoot one or two strong breaking shots in the center and one on each rib. While much of the cut would be blasted down in good lump, some coal would be left hanging at the back and ribs. With hand loading, the miners would have time to pull this coal down with a pick between cars and eventually would clean up the place ready for the cutting machine. The loading machine, however, cannot get this coal down and its operation would be delayed while the men were doing the necessary pick work.

Jan 1, 1929

At the meeting of the American Institute of Mining and Metallurgical Engineers, G. S. Rice, Chief Mining Engineer of the U. S. Bureau of Mines, announced the definition of a gassy mine. This definition has been awaited with much interest, especially by the Safety Committee of the Rocky Mountain Coal Mining Institute. It applies to the whole area of all mines, any part of which is on the public domain of the United States. Consequently it will be of wide application in the western part of this country. The safety committee of the R. M. C. M. I. has been hopeful that the Institute would adopt this definition without exception as the codes of rules to be recommended at all mines in the Rocky Mountain area. The statement follows: "The U. S. Bureau of Mines believes that all coal mines are potentially gassy; but for purposes of administration in respect to prevention of explosions and fires, the Bureau recommends the following classification: "Class 1 coal mine-A practically non-gassy mine in which flammable gas in excess of 0.05 per cent cannot be found by systematic search. "Class 2. coal mine-A slightly gassy mine in which (a) flammable gas has been found, ? but in quantity less than two per cent in still air in any active or unsealed-abandoned workings; or (b) flammable gas can be found, but in quantity less than four per cent, in some place from which the ventilating current has been shut off for a period of one hour; or (c) flammable gas can be found,* but in quantity less than one-fourth per cent in a split** of the ventilating current; or (d) flamamble gas is found in quantity greater than' specified rate*** of not more than 25 cu. ft. per minute. "Class 3 coal mine- A gassy mine in which flammable gas is found in quantity greater than specified for a Class 22 coal mine. GENERAL NOTES REGARDING DECISION NO. 3 "(A) Flammable gas found in coal mines is, with rare exceptions, methane. In coal-mining fields where natural gas is found in lower geologic horizons by deep wells which pass through or nearby the coal mines, there have been rare instances of la leakage from the well. Natural gas is chiefly methane; that constituent almost always forms more than 85 per cent of the whole, but it usually contains ethane, propane and traces of butane also. Therefore if the latter gases are found in mine air it is an indication of leakage. The lower limit of explosibility of methane-air mixture when there is turbulence of five per cent and of natural-gas-air mixtures with about ten per cent ethane and associated hydro-carbon gases is 4.6 per cent. The limit therefore varies with the character of the mixture. " (B) To determine the proper classification of a coal mine, it is advisable that systematic testing and sampling be done at least three times in a period of not less than 72 hours. All tests and samples of the mine air, except one, must show an inflammable-gas content less than the maximum limit of the class to which the mine is assigned. In other words, a tolerance of one test or analysis may be permitted to provide for a mistake or a very exceptional occurrence. "(C) When a new mine is being opened in a coal field where existing mines are generally gassy, it is common sense to assume that similar conditions will be found in the new mine, and its development and equipment should be based upon the expectation that it will be assigned to Class 3."

Jan 1, 1926

By J. B. Forrester

In the operation of the coal mines in Utah few adverse conditions confront us. Physical conditions for the economical extraction of the coal are as near perfect as it is possible for them to be. Still several obstacles are encountered to keep up our interest and prevent us from getting in a rut. Of these I shall speak only of Burning, Wants, and Sluffing of Ribs. Should one travel the outcrop from Ivy Creek in Emery county to the Utah-Colorado line, there would be one outstanding feature indelible impressed upon one's mind. That feature is the omnipresent indications of burning in place. Viewing the eastern escarpment of the Wasatch Plateau from a distance, many splotches of dark red are plainly seen always lying above the coal floor. This stratum is a felspathic sandstone, appearing as a white line running the full length of the above escarpment and about midway between the floor of the valley and the top of the plateau. The coal bearing complex consists of shales, sandstones and coal. This complex varies from two hundred to eleven hundred feet in thickness. The number of coal seams are exceedingly variable. As a rule the argilutites form the bulk of this complex. This material is baked by the burning of the coal and the iron present is oxidized to the ferric state, coloring the shale to a dark red. This baked material forms a shingle tales that in places cover the entire complex. It is natural to expect that the most extensive burning is in the canyons facing to the south and east and on the south slopes of the ridges running to the east or west. Such, indeed, is the case. Still in this arid region many crop fires have existed upon the north slopes, especially in those canyons that face to the east. In fact today, instances are not rare where grassy north slopes, heavily timbered with balsam and fir that have attained a diameter of 14 to 24 inches, are found growing upon the disintegrated baked shingle and later development proves that the coal has been burned at least 500 feet back from the outcrop. Still these conditions are not normal. In this arid climate the south and east exposures are steep and barren, except for the scrub pine, cedar, mahogany and kindred semixerophytes. Bunch grass is also a lover of such exposures. There is very little soil found in such places; it is either blown away as fast as formed or washed away by the rare torrential rains, or the rapidly melting snow. Thus we see that the physical conditions are favorable for the starting and maintainence of outcrop fires. This brings us to the probable origin of this phenomenon. There are four probable ways' that such fires, could be started, namely:

Jan 1, 1921

By J. Kendall Hales

Jan 1, 2005

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

(Referring to map) If there are any methods to improve on this I would like to have some suggestions on it. The maps there are on a scale of one inch to two hundred feet. At the time of each extension a letter is used and a line drawn across the entry and the room. The date of the extension is given up in the margin of the map. Here is an extension made April 6th. Extension L is shown in each one of the rooms, November 29th. N-you see the two rooms have been finished down into here. 0-the last extension, has just been stopped, and the three working rooms. Now, one of the features of this plan, when the rooms have been stopped, the line is drawn straight across. When the room or entry is still going, there is a small projection beyond the line, indicating that the next cut is changed. When the distance cannot be ascertained by the engineer, he gets the distance from the mine boss or some other source which is reliable, and that is put on in a dotted line. That gives you a complete story. Anyone looking over the map can see immediately every place that was working at the time of this extension, every place that is inaccessible, and get a complete picture. The extension of the coal is put on the extension at each extension. The survey stations are put in, showing each survey point. The pillars when they are pulled-only the pillars that are pulled are cross-hatched. The whole map is in cross-hatch without any regard as to what pillars are pulled. If a little stump is left in, that is shown on the map. The engineer only shows what pillars are pulled that he has actual knowledge of, or has been given to him in detail by the mine foreman. I believe that concludes the work on the mine map, and there is certainly room for a lot of improvement on most of the mine maps which we have been getting into the office. PRESIDENT PRYDE: Does anyone want to ask any questions? Any questions about the leasing regulations? I want to say there are several leases in the Rock Springs field, and when Mr. Smith comes on one of his visits the Rock Springs Institute have asked him to address them on the leasing proposition.

Jan 1, 1924

The tenth annual Mine Resale Evaluation was held in conjunction with the RMCMI 2001 convention at the Steamboat Springs Sheraton Resort, Steamboat Springs, Colorado June 23 through 26. The purpose of the mine rescue evaluation program is to provide an opportunity for mine rescue teams to learn new skills and improve their existing ones in a non-competitive environment. Several staged ?disaster? scenarios were held where the teams are called upon to exhibit their life saving abilities. The evaluators meanwhile are offering suggestions, both verbal and written, to help the teams better understand the situations presented them. This non-competitive environment allows the teams to work together and share their knowledge with fellow mine rescue teams providing everyone with a positive learning experience. Mine Rescue Chairman Bill Balaz, Balaz & Associates, was in charge of coordinating the events. Six teams consisting of seven to twelve members each (totaling 60 members) participated in the three-day event. Each ream was required to respond to direr different real-life scenarios plus a written general knowledge test daily. Cindy Burnham has assisted Bali, for a few years. Her responsibilities include grading all of the written tests. This year's tour professional evaluators included Art Seanz (Hazardous Ma¬terials) of Western Environmental Associates ; Guy Norton (Ropes), Guy Horton Rope Rescue; Mary Bailey (Medical), MBA Training and Morley Hense (Confined Space). Carolyn Durga, BHP Coal, also assisted in hazardous materials and medical scenarios. They each provided three different challenging mock situations per day per team. The teams had no prior knowledge of what the scenarios would be as details were provided only as they arrived. Ten volunteer victims added much drama and excitement to the event. Their realistic enactment, complete with false blood makeup and severed limbs, made for some very tense scenarios. The Mine Rescue Teams participating this year were BHP LaPlata, BHP Navjo, BHP San Juan, all from Farmington, New Mexico; Bridger Coal Co., Rock Springs, Wyoming; Sabine Mining, Longview, Texas; Solway Minerals, Green River, Wyoming and Western Energy Co., Colstrip, Montana. Many new friendships were made and much knowledge shared. A swap meet was held Saturday afternoon for the teams to exchange miscellaneous equipment, hats, shirts, etc. The trams were asked to evaluate the program and the evaluators. They responded with many positive suggestions that will help improve the upcoming events in the years to come. Culmination of the Mine Rescue program was a Tuesday morning awards breakfast where the teams were presented with trophies. Each member was also given a gold pin with the words Continuing Challenge - Ropes.' The pin was the first in a series that will be given over the next few years. The participating victims and evaluators were also commended for their outstanding efforts. Special signed "Victim" shirts were given to select volunteers. Sponsors for the Mine Rescue program were Flanders Electric Motors, Magnum Metals, Rocky Mountain Electric Motors, Sedona Consulting and Balaz & Associates. Many hours of volunteer tine and effort from various family members of participants helped make the 2001 event a huge success.

Jan 1, 2001

The morning session opened at 9:00 a.m. and was presided over by Mr. George A. Nugent, Manager Mining Division, Peter Kiewit Sons' Company, Sheridan, Wyoming. The first speaker was Mr. Jack Huebler, Vice President Research, Institute of Gas Technology, Chicago, Illinois. Mr. Huebler joined IGT in 1961 as Director of IGT's contract research program, a major part of which is IGT's extensive coal gasification work. He is also an adjunct associate professor at Illinois Institute of Technology, teaching gas utilization. Before joining IGT, Mr. Huebler spent 20 years with Surface Combustion Corporation where he was chief research engineer. He developed, designed, and constructed a wide variety of heat processing equipment and the associated chemical processes and was involved in applied research in heat treating, gas chemistry, and gas-solids reactions. He has carried out extensive research on the heat treating of ferrous metals, oil gasification and gas combustion, and has made major contributions to the development, construction, and operation of large-scale industrial furnace equipment. He received B.S. degrees in 10th chemical engineering and mathematics from the University of Michigan in 1941. He has 60 publications including 15 patents. He is also a world traveler in the field of engineering. Mr. Huebler's subject "Gasification of Western Coals." (See Index for printed text of Mr. Huebler's paper.)

Jan 1, 1972

PRESIDENT WETZEL: The meeting will come to order. We are pleased to see a few of the more hardy survived last night's-ordeal and are present this morning. The Secretary has some correspondence which he will read. SECRETARY WHITESIDE: Gentlemen, I have a couple of telegrams and a letter which I would like to read to you at this time. First, a telegram addressed to Mr. Wetzel: "Regret greatly necessity canceling my plans to be present at meeting. Appreciate your conveying my best wishes to members for successful and profitable session.

Jan 1, 1942

D. HARRINGTON: Owing to lack of funds, the United States Bureau of Mines have made no experiments in the Bruceton mines in the use of mudite. MR. McAULIFFE: I doubt that mudite cam be delivered at fifty cents a ton and that a mile of heading can be treated with mudite for ten dollars. You could not dig a ton of sand out of a sand hank for that money. L. C. CLARE: The tram road leading to Wattis mine crosses a shale bed and it is easy to screen the shale through a %-inch sieve and load it into a mine car. W. J. REID: A slow trip passing through a mudited entry will dislodge practically no dust, a rapid trip will make air disturbance enough to coat the cars with fine dust. MR. PRYDE: We have used mudite on stoppings around a fire in Reliance and for two months thought they were getting good results, but the fire was found to be drawing air and to be spreading. This mudite was smeared over the stoppings with a trowel. After this apparently failed we used dry adobe.

Jan 1, 1925

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

Jan 1, 1926

Jan 1, 1996