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In this very interesting paper, Mr. Harrington mentions a considerable variety of materials suitable for use in the rock dusting of coal mines; this suggests that you may possibly be interested in same purely theoretical figures tending to show the superiority of gypsum for this purpose. Some of the gentlemen present have found difficulty in applying a thick, adherent coating of dry gypsum to the ribs and roofs of their workings, for which reason pulverized gypsum will perhaps be chiefly useful for the loading of barrier troughs. In view of the function that rock dust is expected to perform in case of a coal-dust explosion, it seems obvious that the most efficacious dust will be the one that can absorb the most heat and absorb it most rapidly. The customary rock dusting materials differ considerably in this respect, depending principally upon the facility with which they can be decomposed at the temperatures encountered in a coal-dust explosion. Such stable materials as silica, anhydrite and flue-dust vary but slightly in their heat-absorbing capacities, the specific heats of minerals in general ranging between 0.19 and 0.22; on the other hand, gypsum and limestone, as well as certain argillaceous materials such as shale, adobe, etc., are capable of absorbing additional heat through their chemical dissociation, although, as will appear later, it is questionable whether the amount of heat thus absorbed, in the case of limestone, shale, and adobe, is large enough to have any practical value. As to the temperature developed by a coal-dust explosion, the Bureau of Mines reports one test in which gold foil was melted, and others in which silver foil was melted, but not gold; hence 1832° F. (1000° C.) seems a reasonable figure to assume for purposes of calculation. Normal temperature is taken as 68° F. (20°C.). The other fundamental data required for the computations as cited by various authorities, are as follows: [Specific heats Gypsum : 0.259 Calcium sulphate, anhydrous. . .190 Limestone 0.216 Lime 0.239 Clay, shale, silica, etc. usually not exceeding 0.220 Carbon dioxide .:0.217 Steam (at atmospheric pressure)0.500 Heats of formation CaSO4+2H2O-4.606 Kg-cal. per gram molecule, or 48.2 B:t:u.' per pound of gypsum.- CaO +C0,42.5 Kg.-cal. per gram molecule, or 765 B.t.u. per pound of limestone. Latent heat of vaporization of water. from and at 100°C.. 535.9 Kg.-cal. per kilogram (964.6 B.t.u. per pound).] Computations will be based on the Fahrenheit scale and British thermal units, as probably more familiar in the coal industry. First as to the inert materials: their heat-absorbing capacity per pound is simply the product of their specific heat, say 0.22, multiplied by the assumed rise in temperature, 1764° F., or 388 B.t.u. per pound. Gypsum, CaS0, 2H.0, though apparently perfectly dry, contains 21% of combined water. When gradually heated it will have liberated three-quarters of its water freely by the time it reaches 250° F.; the remaining one-quarter is retained to a somewhat higher temperature, but the last of it will have been expelled at 482° F. For calculating the total heat absorbed in raising gypsum (or its products) to the temperature of a coal-dust explosion, no serious error will be intro-

Jan 1, 1925

MR. HARRINGTON: I would like to ask Mr. Bottomley if they fire their shots while the men are in the mine? MR. BOTTOMLEY: No sir; the shot-firing law in our State requires the shots to be fired after the men are out of the mine. We fire more shots than we did under the hand method of loading. Where formerly four holes were drilled, now we drill eight, using the same amount of powder as we did formerly, perhaps a little more, but we use a slower grade of powder. CHAIRMAN LITTLEJOHN: Any further discussion, gentlemen? MR. GIBSON: Mr. Chairman, I would like to ask Mr. Bottomley, if, in his shot-firing system, as I understand it, he has a very high coal and is working something like eleven feet? MR. BOTTOMLEY: Something like that. MR. GIBSON: I read the article that you referred to. Did you use both the first and the second delay explo¬ders in shooting the coal? MR. BOTTOMLEY: We use the ordinary fuse. MR. GIBSON: That is what I wanted to find out; whether you use the delay exploders and the detonators. In Utah, we are getting away from the fuse altogether, because we do not think it is accomplishing anything to use the electric light on the cap, and' at the same time shooting with fuse. We are defeating the object we might gain in using the electric safety lamp. That is a point that might be discussed a little further. MR. E. H. JOHNSON, The Coloder Company: I would like-since it is a general opinion that mechanical loading breaks up the coal, to ask Mr. Bottomley, if he finds a larger percentage of small coal, or how much, through the use of the mechanical loaders? MR. BOTTOMLEY: We do not find any great difference. In fact, we have succeeded in improving our lump coal percentage, and that is important, because it is largely domestic. At first, when the machines were installed, the boys shot the coal too hard, and we fell down a little, about two or three per cent, the first month, in our lump percentage, and we tightened up a little and changed our methods in shooting and got on to the stunt of drilling more holes and getting a slower grade of powder. We could not load as much coal in one day as we could before, but we did succeed in in. creasing our lump coal percentage four and a half per cent over the hand method, and that is quite a factor-quite an important factor and since our domestic trade is over with, we loosened up on the shooting and we are running about the same as we did with the hand loading, maybe a half per cent more, or one per cent, but pretty much the same. MR. SHUBART: Your coal is very high? MR. BOTTOMLEY: Yes. MR. SHUBART: Have you tried sunbbing the coal before shooting? MR. BOTTOMLEY: No, we have not tried that. It is very hard coal to shoot; we have no defined cleavage in our coal. It is the worst coal I ever saw to shoot. We do not try to snub it. Formerly, as I said, the miners drilled four holes, pretty well up near the top, and then four holes down, within about three feet of the bottom. It is the same thing as a snub shot, and that we find is the best method for shooting the coal. We have not tried any mechanical device for snubbing as yet. SECRETARY SHUBART: At one mine I saw snubbing tried with a Jeffrey undercutter with a seven-foot Jeffrey bar. This mine, by the way, is very similar to Mr. Bottomley's condition. They have very high coal, so the snub cut is a small percentage. They cut a seven foot undercut and raise the machine on an eight inch tie and undercut five feet to give the effect of a snub cut, 14 inches at the front of the cut, and then six inches at the back of the cut. They made a very marked increase in lump. (The bug dust would be a small percentage of the total coal), and they increased the percentage of the slack at the same time. They found a decrease by reason of the easier shooting of about 15 per cent in their slack. In other words their nut and lump coal ran considerably higher and their slack decreased 5 per cent with the snubbing cut. Mr. Bottomley, I believe, understands those conditions.

Jan 1, 1926

By Thomas Foster

One of the most dreaded things which mining men sometimes have to contend with is underground mine fires, which are both dangerous and expensive. In the Reliance mines we have had considerable trouble with mine fires. We have at the present time five different fire zones, three of these zones give us considerable trouble and the other two have not given any trouble since they have been walled off. Fire Zone No. 1 comprises No. 2, 3 and 4 South Entries, about 50 acres are enclosed in this zone. Fire Zone No. 2 comprises the main drift entry from the mouth to the Old Boundary Plane and extends to the crop line, about 10 acres are enclosed in this zone. Fire Zone No. 3 comprises 1 and 2 North Entries from the main slope to the Old Boundary Plane, a distance of about 1,200 feet, about 15 acres are enclosed in this zone. Fire Zone No. 4 comprises 11/2 and 2 North Entries, a distance of 1,100 feet between New Slope and Old Boundary Plane, about 15 acres are enclosed in this zone. Fire Zone No. 5 comprises the inside end of No. 11/2 and 2 North Entries and 3 North Entry from the New Slope to 30 room, a distance of about 2,600 feet along No. 3 North Entry, about 20 acres are enclosed in this zone. The first mine fire started in No. 2 South Entry in No. 1 zone in 1914. Inside of No. 7 room on the high side of the entry, there was a soft piece of coal. There were no rooms driven in this coal and one day a fire was discovered in the solid pillar on the high side of the entry, work was started at once to load out this fire. and several places was driven into the pillar and cribs built where the coal was taken out, but this method proved a failure and a sand pack was put up along the entry between the track and the high rib. This consisted of timber set about 3 feet from the rib and 2-inch boards put behind the timber and sand or adobe put in between the boards and the ribs, and this method gave very good results except that it required close watching as the sand would settle and let the smoke out between the roof and the sand. Fire broke out in No. 3 South Entry in No. 1 zone in the summer of 1919. We sealed this fire off by building 36 fire stoppings, which also enclosed the fire in No. 2 South Entry and we have never had any trouble with fires in this zone since it was walled off. The fire started in No. 2 -zone in 1919 and has been very active ever since. When this fire was first discovered we built new stoppings in front of the old one in the room necks; we also opened up some of the room necks and loaded out part of the burning coal and rock but this did not help any, the fire, would burn out around the stoppings also burn along the roof between the top coal and the roof sometimes nearly across the entry. Several holes were drilled from the surface to the fire area and flushing the fire was tried but this was also a:\, failure, the rock above the coal was so hot that the mud would dry in the hole and fill it. In 1921 we started to take down the top coal along this entry, timber the entry and put 2-inch boards behind the timber and fill in between the coal and the boards with sand or adobe. We have at present over 1,000 feet of this work done and it has given us better results than any other method that we have tried. As the coal burns out behind the timber the weight breaks the timber and it is necessary to renew some of it. Fire broke out in No. 1 North Entry in No. 3 zone in 1922. There was a stopping in this entry that had been put in when the entry was finished some few years before. The fire burned around the stopping on the low rib of the entry, we built another stopping in front of the old one taking down the top coal and extending it up to the roof also digging in both ribs and setting the stoppings into the coal about 18 inches. This fire did not cause any trouble until June, 1924, when we discovered this fire was very active on the inside

Jan 1, 1924

Past President Ralph Moore opended the meeting at 9:30 a.m. He thanked all the committees for their part in making the 1977 meeting the success is was. He then turned the meeting over to President-elect, Shirl McArthur. President McArthur called on the Auditing Committee to present its report. Gabe Ishley, Chairman, read the report and asked that it be approved. A motion was made, seconded and carried. Loren Linville gave his report on registration and new members which figures are in the Monday a.m. business meeting of the Proceedings. The Resolutions Committee was asked to give its report. William Bear, Chairman, submitted the following: (1) RESOLVED: WHEREAS, in the year since the last convention of The Rocky Mountain Coal Mining Institute, the Institute and the coal mining industry have suffered the loss through death of the services of: John A. Garcia John B. Huehes H. B. Lindeman Richard B. Miller Charles Pliley Wilford Ruff James Westfield

Jan 1, 1977

By Lyman Fearn

Men and institutions are what they are largely because of inheritance. Out of the past comes experience that enables men to build more wisely than did preceding generations. The field of possibilities has widened as the horizon of men's vision has been extended. The realization of these possibilities has depended largely on the application of men's natural endowments, brain and brawn, to the problems at hand. In the field of mechanized mining, Wyoming has a greater percentage of men with vision, who have a realization of the possibilities of mechanized mining, than any other state in proportion to tonnage production. With the introduction of mechanized mining systems have come problems that have caused the men who are connected with the safety work much thought. Discussions on mechanical drilling, cutting, loading, conveying, haulage, etc., have come in for their share of the debate. There have been a few attempts made to show that mechanical mining is safer than are the more primitive ways of doing underground work by man power. We also have a number of places in the coal producing States of the United States, where the mechanized systems have been abandoned chiefly on account of the safety element involved bringing about condemnation of the system by State inspection forces. Certain types of scraper systems have been condemned, and some have voiced opposition to long faces. This would lead us to believe that the question is still a debatable one as far as the safety element is concerned. It is only fair that we discuss the operations of mechanical systems and from the results obtained take analysis of conditions as they exist, basing our conclusions from the results obtained.

Jan 1, 1928

[ATZ, Inc. American Mining Congress Anaconda Minerals Company Andalex Resources, Inc Arapahoe Energy Consultants Atlas Powder Co Becor Western Inc. Mr & Mrs. Bernard Bernstrom Black Beauty Resouces British Mining Consultants (USA) Limited]

Jan 1, 1988

Jan 1, 1971

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Jan 1, 2000

Jan 1, 1973

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

By W. T. Ferguson

Mr. Chairman, Members of the Rocky Mountain Coal Mining Institute: It seems particularly appropriate that we come at this time to make a report on a phase of mechanical, mining of coal which had its birth in this region and was cradled and nurtured here until it assumed a lusty manhood that has made its presence felt in every coal field in this country and in foreign fields as well. More than twenty years ago shaker conveyors were introduced into the states covered by your Institute, and immediately, forward looking men saw that here were possibilities for the operator's dream of a continuous flow of coal from face to tipple, if this latest device could be made self-loading. The skill and ingenuity of men in the Rock Springs district quickly brought this about and in but a few short years .more coal was being loaded by Duckbills in this field than by any other means. Not content with this outstanding success, still other men dreamed of having this same Duckbill moved across the face under its own power, and so this same district produced the first power swing Duckbill.

Jan 1, 1947

Jan 1, 1979

Jan 1, 1978

Jan 1, 1967

Profiled on these pages are the eight RMCMl 1998 Scholarship Award winners. Six of the eight winners were present as guests of the lnstitute at the June convention at Snowmass Village, Colorado. Each received recognition at the Institute Awards Luncheon Sunday. June 28. 1998. Each state vice president served as host for the collegiate winner and his firm provided travel and hotel expenses. In addition to receiving a plaque from the Scholarship Chairman, Jim Mattern, each winner receives $1.000 tuition credit for the coming academic year, as well as transportation, hotel lodging and meals at convention as guests of the Institute. Because this IS a continuing award, the winners from the previous year also receive a $1,000 tuition credit in their senior year if recommended by the dean of the college or university and if they remain full time students. A resident from each of the eight RMCMI member states is selected from among Board approved institutions. Criteria for these awards made annually is that the recipient (1) Is a full time sophomore student who will use the tuition credit during the junior year. (2) Be both a U.S. citizen and a resident of the member state. (3) Maintain 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 includes curricula other than in the mining departments, but in engineering disciplines, such as geology, mineral processing and metallurgy. Through annual donations of $100 or more. the Patrons of the Institute fund the scholarship program. A listing of current donors is found elsewhere in this book. Donations to this worthwhile program are payable to RMCMl Patrons and may be mailed to the RMCMl Office, 3000 Youngfield Street, Suite 324, Lakewood, Colorado 80215. Profiles of the 1998 Scholarship Winners follow. [ ] ARIZONA WINNER Christopher L. Delp University of Arizona Christopher is the son of Drusilla and John Delp of Tucson. He is pursuing a degree in Mining Engineering as a junior at the University of Arizona. He enjoys outdoor sports including skiing, mountain biking, golf, and hiking. He also enjoys reading, ghost town and old mine exploration, computer, Japanese conversation, and sketching cars and other forms of transportation. Chris hopes to attain a Masters Degree. [ ] COLORADO WINNER Matthew D. Lengerich Colorado School of Mines Matthew, the son of Judy Lengerich, Durango, Colorado and Ronald Lengerich of Redlands, California, is pursuing his degree in Mining Engineering with a 3.93 GPA. He is a member of the National Honor Society and the German National Honor Society. An avid outdoorsman, Matt also finds time to pursue music and theater. He was unable to attend convention this year as he was on a collegiate trip to South Africa. He is Co-President CSM Newman Group and Youth Leader at Christ on the Mountain Catholic Church.

Jan 1, 1998

Jan 1, 1934

Past President Shirl McArthur opened the meeting at 9:30 a.m. He called on the Auditing Committee to give its report. Stan Shubart, who checked the financia1 report of the treasurer, read the report. He asked that it be approved. A motion was made, seconded and carried. Shirl thanked all the committees for an excellent job in making this meeting a most successful one. Special thanks to Park Lamborn for a fine program and to Gussie Whiteside for all her efforts in behalf of the Institute. An increase in salary was voted for the secretary-treasurer. It was decided to return to Vail for the 1979 convention. The Resolutions Committee was called upon to give its report. Roy Coulson, Chairman, submitted the following: (I) RESOLVED, Whereas, in the year since the last convention of The Rocky Mountain Coal Mining Institute, the Institute and the coal mining industry have suffered the loss through death of the services of: O. F. Bridwell C. L. Book O. F. Lewis Frank Kolar O. H. Littrell L. B. Phillippi Weston L. Potter George C. Trevorrow

Jan 1, 1978

Jan 1, 1958

The Morning Session of the Forty-Eighth Meeting of the Rocky. Mountain Coal Mining Institute convened in the Little Theater of the Broadmoor Hotel, Colorado Springs, Colorado, at 9:30 a.m., June 3, 1952, Howard B. Crandell, President, presiding. PRESIDENT CRANDELL: Gentlemen, the meeting will come to order, and I would like to introduce to you your Chairman of this meeting, Mr. John B. Hughes, General Manager of the Union" Pacific Coal Company, Rock Springs... (Applause) CHAIRMAN HUGHES: From the activities around last night, I supposed there would be quite a few that would be unable to attend this morning. I am sorry there are not more here because I am sure we have some interesting papers. First on the program this morning is, The Effect of Continuous Mining on Today's. Coal Industry by Mr. William Wearly, Vice President of the Joy Manufacturing Company. Mr. Wearly: (Applause)

Jan 1, 1952

By M .. K. Stewart

(Here follows descriptive movie.) CHAIRMAN KNOX: Thank you very much, Mr. Stewart, for this wonderful paper and picture. We are indebted to you. It certainly is the most interesting thing I have ever seen in connection with wire rope, except paying for it. I think there are a lot of questions that could be asked to bring out some points that we are not generally understanding of. Are there any questions at this time? I know Mr. Stewart will be glad to answer them. Come up to the front, Mr. Stewart. MR. STEWART: That's all right, thanks. CHAIRMAN KNOX: If there are any questions, let us have them. (No response.) Well, we will pass on to the next paper. CHAIRMAN KNOX: Our next paper will be "Self-Preservation, with Some Comments on Mechanical Loading," by Benedict Shubart and Charles Schloss.

Jan 1, 1935