Search Documents

Mr. Pickett's remarks were primarily concerned with the legislative aspects of the coal industry. Mr. Pickett stated that as a result of the 1952 election, only two senators and eleven representatives are now in the legislature who have ever served under a republican administration. He said there are 425 legislative issues now on the floor of Congress concerning the coal industry, but the coal industry has difficulty in legislation, because, although there are 31 coal states, only 11 states produce more than 5,000,000 tons per year, and 11 states produce between 500,000 and 5,000,000 tons of coal a year. In these states there are 44 senators and 195 representatives, less than a majority in either house, if all could be counted on to support the coal industry. An important committee to the coal industry is tile House Ways and Means Committee, composed of 25 members, 15 Republicans and 10 Democrats. Even with the support of the senators and representatives from these 22 states, legislative action is difficult.

Jan 1, 1954

By D. C. McClure

MR. McCLURE: Mr. Chairman, you sprang a surprise on me; I really came over here for a good time. Gentlemen, I am not at all qualified to pose as an expert on pulverized fuel; I have merely been making some rather interesting observations, and unfortunately at the present time, a great deal of substantial data, the technical data, I don't happen to have with me; it is still in the process of being calculated, but I will be very glad to tell you some of the observations as I have made them, and in as truthful and complete a way as I can. The question of how we would handle fuel became a very pressing subject in this new Valmont electric plant, which is now under progress. We have studied the methods of burning fuel for a number of years on different types of stokers at the existing plants in Denver; we are burning it with a natural draft chain grate and with underfeed and with forced draft chain grates, and I am very frank to confess at the present time that I have no answer as far as stokers are concerned for a better solution of the problem of burning lignite. In other words, I could not tell you that this or that is a better type of stoker to use for that coal. However, to boil the thing down, after considerable trials, the underfed stoker was chosen as the one most adaptable for the utilizing of lignite fuel if stokers are to be used. In other words, the chain grate was put aside. I might say in support of the chain grate, the prime reason for which that type of stoker was condemned, as far as lignite goes, is the initial investment charge and the large maintenance which is involved.

Jan 1, 1923

At 10 a. m. registration was commenced and completed. At 11:30 a. m. the meeting was called to order by the President, William Littlejohn. There was no unfinished business, new business nor reports of committees. The minutes of the previous meeting, as published in the proceedings, were approved. The report of the Treasurer was referred to the Auditing Committee who were auditing the report of the previous year. At 2 p. m., President William Little- john called the meeting to order for study session. Mr. J. Samuel Pyeatt, the new president of The Denver & Rio Grande Western Railroad, ad- dressed the Institute at length, expressing his pleasure at the opportunity of meeting the coal operators, pledging his cooperation toward the solution of the mutual problems that are arising. He reviewed the change in the Western Industrial situation; explained how the revenue of The Denver & Rio Grande Western Rail- road was being received from freight rates, only twenty-four per cent above the rates of 1914, yet laborers receive 97 per cent more, supplies cost 58 per cent more, showing that no reduction in rates can be expected unless other conditions are adjusted. He gave figures to show the immense sums, aggregating ten million dollars, that have been spent on improvements in the last ten years. The railroad is improving and will continue to improve. Mr. Pyeatt feels that the serious troubles of the railroad are over and that with the cooperation of the shippers, better service and more profits are ahead. He showed the increase in rates on farm products to be only 48 per cent, as against an average in- crease in price of farm products, them- selves, of DG per cent. The position of the farmer is not as serious, nor un- fair, as has been claimed. More equitable legislation is promised, and this is needed to offset the efforts of demagogues to deceive the people as to the actual facts. Much equipment has been put into the railroad, much new and powerful equipment, and ten of the largest narrow gauge locomotives ever built have just been ordered, engines that will do the work of three of the present locomotives. This ratio of improvement will be maintained throughout the narrow guage system, and the Rio Grande will not lag behind the shippers and the operators in co- operation. The President answered Mr. Pyeatt's remarks, and then called the meeting to order for discussion. The study sessions were held; papers were read by .J. H. Emrick, "Cutter Bits"; D. A. Stout, "Experiments in Mining Methods," and Harry Petersen, "Permissible Powder and Cushion Shooting." Tuesday, February 17, 1925 The meeting was called to order Tuesday morning at 10 a.m., and papers read by: F. C. Miller, "Safety Methods With The Colorado Fuel & Iron Company"; this was supplemented by a talk by 0. C. Irwin on "Automatic Mine Fan Control," illustrated by models of the apparatus used; Samuel Tescher, "The Operation of a Gaseous Mine."

Jan 1, 1925

By R. A. McAllister

The haulage system employed to convey coal from the face to the outside, dates back to 300 B. C., when slaves carried the mineral from the face to the consumer. The British discovered coal on their island about 800 A. D. and they were the first people to make practical use of coal and make coal mining a successful operation. The Britons carried cargoes of coal in their trading expeditions long before Columbus discovered America. The early history of mine haulage in the British mines relates to women with baskets, a practice still in use in Korean mines. Coal was discovered in America in 1679. The first mine worked in the United States was opened at Richmond, Va., in 1770. The haulage inside consisted of a crude sled loaded with, sacked coal ready for the market and drawn by a mule. The tipple consisted of the very simple operation of loading the sacked coal to the back of a lame mule, which represented the transportation system between mine and boat. The capacity of the boat was one ton and this large production of coal was intrusted to a small boy, who delivered to any place in town his bushel basket filled' with winter fuel. One daring coal operator shipped fifteen tons of coal by boat to Philadelphia and the man in charge had to seek employment to pay his board while finding customers for his fuel. A production of five tons per day would hardly attract attention to any system of haulage, add three ciphers and the importance of mine haulage is made very plain to the management. I will consider a production between 3000 and 5000 tons in eight hours and endeavor to bring out the essential features necessary to make the haulage system a regulated precise factor. There are two phases to mine haulage, the mule trip from the room to the motor or gathering party and the main haul to the outside. The motive power, whether done by mule, wire-rope or electric motor cannot be effective if left to the power alone. Conditions must offer no obstacle and it is the removal of obstacles that make the haulage system. This paper will consider a flat seam with the usual jump ups and downs or natural obstacles to be met and mastered by the successful tail-rope or electric system. The pit car is no longer a screening system scattering the fine coal from the room to the outside, adding to the costs by giving employment to road cleaners and polluting the ventilating system with a fog of coal dust. It is not a contrivance with four flat wheels and a labor killer in the room or on the tipple The large producing mine has a pit car with a tight body, roller-bearing wheels, with a self-oiling system that offers the least possible draw-bar pull to overcome the friction resistance, a hand brake conveniently placed and positive in action, a wheel base short enough to make room necks and long enough to

Jan 1, 1921

PRESIDENT MARKS: We have a letter from Mr. Frank N. Cameron, of the Utah Fuel Company, that perhaps I had better read to you. It is addressed to Mr. Shubart, Rocky Mountain Coal Mining Institute (hands letter to Secretary Shubart). UTAH FUEL COMPANY MINE SUPERINTENDENT Castle Gate, Utah, February 9, 1926 Mr. F. N. Cameron, Vice-President & General Manager, Salt Lake City, Utah. Dear Sir: It has now been about nine months since we started the system of having the fire bosses take charge of all shooting and gas inspections at the Castle Gate Mines. We had considerable trouble when we started. Like all other new systems which have been installed, this one was hard to get started and was criticised both by the miners and officials in our own organization, as well as by other organizations in the mines of this county. The older the official and miner was the stronger they seemed to be opposed to the new method. They have no arguments to offer against it, but they know it is not right "because their grandfather did not work it in that way." We know that when some of the other systems were started in the mines of this county, they were fought from all angles. The electrical shooting almost brought the miners at Sunnyside out on strike; their main argument was that they could not make a living if they had to obey the rules that the company was trying to enforce. They also claimed that they could not make enough coal for the day's work by only shooting once at the end of the shift. The same applies to the sprinkling the miners claimed that they would all die of some disease if they were forced to work in a sloppy, wet mine every day. The mining machine was another thing that was hard to install the miners claimed that the company was trying to rob the Door miner out of a chance to make living by installing mining machines to cut the coal. I do not think that the system we have at our mines is perfect-there is still room for improvement in the shooting and inspection of the mines, but I do really think that for safety and efficiency, the inspection department at our mines, working under the new system, is as good if not better than any other inspection department working under the old method in the other mines. I am giving some of the arguments in favor of the new system and would like to hear the arguments against it-if there are any. In cutting the men from monthly to day wages, I do not think it is only the company that benefits by the arrangement, but the fireboss is the one that gets the best of it by the change. How often have we heard the fireboss complain of the hours he had to put in just because he was a monthly man? Under the new wage scale he is paid for every hour he puts in the mines, and when the mines are working every day he makes considerable more than when he was being paid a monthly salary. When the mines are working slow, there is generally some work that has to be done on idle days, or in slow times the force could be cut to a point where some of the work could be done on idle days, and thus the fireboss could be given the preference in this extra work and in this way, his wage could be kept up to the standard monthly salary he was getting before. Under this arrange-

Jan 1, 1926

CHAIRMAN LITTLEJOHN: Some of the members will want to question Mr. Farnham on some of the things he has brought tip, so we will throw the meeting open for discussion. I am quite sure Mr. Farnham will be willing and glad to answer any questions that may be put to him. MR. HOLMAN: I would like to ask Mr. Farnham a question in regard to the Duckbill: How wide a face will it operate without moving the bill? MR. FARNHAM: The Duckbill is a device that was developed in the Union Pacific Mine at Rock Springs, within the last few months, and it is shaped something like, a dustpan, with discharge throat in the rear. They made one seven feet wide and found it was too wide, and the one they are using now is between three and four feet in width. The front section of the conveyor, which attaches to the duckbill, meshes into it to form a sliding section, and the front end of the Duckbill is pushed by the upper segments. I saw one used in a room twenty-four feet wide, and they drew it back after they cleaned out one room and pushed it forward again. MR. HOLMAN: You have no arrangement other than ratchet work? MR. FARNHAM: The ratchet is for forward working and back; the sections are made 12 or 13 feet long, and the stroke of the conveyor automatically works the ratchet; they can ratchet it back; it is a hand device. MR. HOLMAN: They just swing the end of the conveyor across the face to pick up the loose coal? MR. FARNHAM: Yes; they are also planning to use it endwise along the panel face, that and the room work both are quite new in their application, and I do not think the Union Pacific is giving out any results as yet, because the system has not been in use long. MR. HOLMAN: We are planning on putting one in very shortly. MR. HALL: I understand they can swing it over 30 degrees one way or the other, and it goes the same way easily because of the continual jar of the back and forward motion on a 60-degree swing. SECRETARY SHUBART: Take on a comparatively long conveyor, you can get quite a sweep, a large part of the circle. The Duckbill could command quite a large range. For a 12-foot entry, take a four-foot wide advance through the middle of the shot coal, with a 12-foot advance, ratchet back, swing the Duckbill to the rib and repeat; but I do not think they could get as much as 60 degree. on the end of the Duckbill without curving further back. The conveyor is light and not normally set on any permanent foundation. I saw one of Mr. McCarty's first machines, a rather rudimentary one, clean tip a 12-trot entry, 21 tons of coal, in 16 minutes, three men at the face and one at the loading end. MR. FARNHAM: The average time to clean the entries is about an hour-to clean up good-it wouldn't take but a short time; that is why they get this record of several cuts a shift. CHAIRMAN LITTLEJOHN: Are there any other questions you would like to ask Mr. Farnham? MR. HOLMAN: We were discussing this entry driving in regard to the entry loader; an entry loader in advance work, just what you have to do to place the jackbars with the sheave-blocks? Do you dig along the ribs after the coal is shot or do you have any other scheme that could be worked out to a good advantage? MR. FARNHAM: This record is a report I have just received from our Chicago office, without the full details, which I have written for. I am sorry I cannot give you the details. This was an Indiana or Pennsylvania mine, near Pocahontas, not the one where they had an accident. I assume they set the jacks ahead and swung and dumped the coal partly out with a scoop and partly by hand, but the application for that for entry driving is entirely new. The reports stated that they anticipated using that as a standard method of entry driving in the future. I will be glad to see that you get a copy of it when I get the report completed. MR. MONAY: Mr. Shubart, did you say they loaded 12 tons in 16 minutes? SECRETARY SHUBART: Twenty-one tons. MR. MONAY: How long did it take to change the machinery out of there

Jan 1, 1926

[ ]

Jan 1, 1993

"Let us not think of our departed dead As caught and cumbered in these graves of earth; But think of death as of another birth, As a new Freedom for the wings outspread, A new adventure waiting on ahead, As a new joy of more ethereal mirth, As a new world with friends of nobler worth, Where all may taste a more immortal bread." FLOYD W. PARSONS N. CHRISTENSEN JOSEPH F. PETERS GEORGE B. PARKER ROBERT WILLIAMS B. F. DEVINNY

Jan 1, 1942

[HORACE MOSES President Gamerco, New Mexico BENEDICT SHUBART Secretary-Treasurer 521 Boston Bldg., Denver, Colorado ROBT. L. HAIR Vice-President for Colorado VIRGIL M. McKNIGHT Vice-President for New Mexico A. E. GIBSON Vice-President for Utah THOS. FOSTER Vice-President for Wyoming EXECUTIVE BOARD COLORADO: J. B. DICK Walsenburg C. M. BILLINGTON Lafayette NEW MEXICO: W. C. HOLMAN Dawson ROBT. WYPER Gallup UTAH: R. R. KIRKPATRICK Sunnyside GEO. A. SCHULTZ Latuda Wyoming: EDWARD BOTTOMLEY Kleenburn QUINCE RICE Superior]

Jan 1, 1926

Jan 1, 1951

Thomas J. LIEN RMCMI PRESIDENT 1997-1998 on behalf of the RMCMI Board of Directors and Officers of The Rocky Mountain Coal Mining Institute cordially invites you and your family to attend the 94TH Regular Meeting and Convention to be held June 27 thru June 29, 1998 Snowmass Village, Colorado

Jan 1, 1997

Past President, A. Z. Dimitroff, Supervising Mining Health and Safety Engineer, Health and Safety, District H., U. S. Bureau of Mines, Denver, Colorado, opened the Fifty-eighth Annual Meeting of the Rocky Mountain Coal Mining Institute at the Hotel Colorado in Glenwood Springs, Colorado, at 10:30 a.m. His introduction of President Charles M. "Dock" Schloss follows: It is indeed a pleasure to call the meeting to order and to welcome you to this, the 58th regular meeting of the Institute. This morning I have the pleasant assignment of presenting to you a person who has been so active in the Institute, and has worked so closely with many of you, that I am sure most of you have known him much longer than I have.

Jan 1, 1962

PRESIDENT WHITESIDE: I am sure we are very grateful indeed for this very interesting talk that Mr. McClure has given us. If anyone has any questions to ask Mr. McClure I am sure he will be glad to answer them at this time. MR. WEITZEL: I want to ask Mr. McClure whether in the instance he described by-passing the drier, whether there was any rest period between the crusher and the furnace, whether the powdered coal that was not dry was allowed to rest in the pipe or was blown directly into combustion chambers. MR. McCLURE: Yes, it moved directly; there might have been some difference had we given it an opportunity to rest. We just had to get in and get out so as not to interfere with operations. MR. WEITZEL: Your idea is, even though you did use a high moisture lignite, you could store it under water if you eliminated surface moisture later. That is a new idea to me; I always had thought that you had to reduce the moisture down under 2 per cent, and to try to store it with anything more than that, any higher moisture, you would have to break the stuff loose again, as it gets so hard it won't move. MR. McCLURE: It might develop I am absolutely wrong; I am just saying what I observed, and I may have had some unusual condition, which I did not detect; something may actually develop which will make my statement of drying lignite entirely wrong. It was quite a surprise to me, surprise to every-

Jan 1, 1923

The Sixtieth Regular Meeting of the Rocky Mountain Coal Mining Institute convening at the Stanley Hotel in Estes Park, Colorado, was declared in session at 10:10 a.m. by Past President Mike Zakotnik, Jr., General Superintendent, The Kemmerer Coal Company, Frontier, Wyoming. Mike introduced Claude P. Heiner, President, Minerals and Development Corporation, Salt Lake City, Utah; and President of the Rocky Mountain Coal Mining Institute. President's Address Members of the Rocky Mountain Coal Min- ing Institute, guests, visitors and friends: I feel this is a distinct honor to talk to you on the occasion of this 60th regular meeting of the Institute. I once assumed this would be the Institute's 60th birthday, but later found that the first meeting was held in the State Capitol at Denver on November 12, 1912, at which time a comparatively small group of operators duly organized the Institute; a Mr. Weitzel of Colorado Fuel & Iron Company was then elected president and our late and dearly remembered Fred W. Whiteside, whose wife Gussie now carries Fred's work forward, was elected secretary. From Fred's records, early meetings were held semi-annually at rather irregular intervals, so that this 60th meeting is approximately the 52nd birthday of the organization and I am number 44 to serve as president. This latter development, I am sure, was conjured up last year by certain members at Glenwood Springs when I was absent. Anyway, I am honored and trust 'that these sessions will be both interesting and instructive in helping us on our way in the coal business.

Jan 1, 1964

By D. Harrington

At the time of mine accidents one frequently hears the expression "there will be accidents as long as there are mines", or it may be varied to state that the accident in question was unavoidable, or something similar indicating inability to prevent accidents. However, it is the opinion of the writer, after over twenty-one years experience in both coal and metal mining, seven years being spent wholly in safety work, that by far the greater number of all accidents is due to carelessness or negligence. This carelessness or negligence may be on part of the victim of the accident or of one of his companions, or on part of his employer or possibly even of the inspector or safety man, and in some cases all of these agencies are involved. It manifests itself in various guises, one of the most serious being violation of state mining laws or regulations or of mine rules, and frequently the rules of ordinary common-sense. The cause very frequently is that trait in human nature to "take a chance" and it has been the writer's observation that the worst offender is the old-time miner who has come safely through many years experience, who was mining when the "safety man was a baby", and who clings to old-time ideas and practices and has "no use" for "newfangled" present-day "notions". Unquestionably, there are accidents, wholly unavoidable and many are caused by ignorance and by the new-comer in mining, yet as previously indicated, the writer's observation is that the old-timer is by far the worst offender, bringing grief to himself, companions and employer. Of the numerous manifestations of carelessness and negligence in connection with mine accidents, which have come to the notice of the writer, only one will be treated in this paper, viz: Violation of State Mining Law, and mention will be made only of explosions and major accidents in coal' mines with which the writer came in personal contact as investigator. In most cases, in addition to mine inspection after the accident, the writer heard the evidence given at Coroner's inquest and thus was enabled to for¬mulate fairly definite impressions as to events and conditions leading up to the occurrence.

Jan 1, 1922

Pictured on these pages are the six RMCMI Scholarship Award Winners for the 1985-86 year followed by a brief profile. Five of the winners were present as RMCMI guests at the June convention at Tamarron to receive their recognition plaques at the welcoming session held Monday, July I, 1985. In addition to the plaques, each winner will receive $500.00 to be used toward tuition in the coming academic year. Also, as this is a continuing award, the winners from the 1984-85 season, will also receive an additional $500.00 for tuition use in their senior years provided they have maintained a good academic standing. Criteria for these awards is (1) 'That the award be made in the spring to a sophomore student to be used toward tuition during the junior year. (2) That the recipient be both a U. S. citizen and a resident of the state involved. (3) That the recipient have good academic standing, be pursuing a degree in a mining related field and have an expressed interest in Western coal as a possible career path. Contributions to this worthy project are tax deductible to each individual RMCMI member as well as firms, businesses and corporations. Checks payable to RMCMI Scholarship may be mailed to the RMCMI Office at 777 Nile Street in Golden, CO 80401. Profiles of the 1985 winners follow: [ ]BEVERLY MOON Colorado School of Mines Beverly is a resident of Greeley, Colorado. She maintains a 3.1 grade average at the Colorado School of Mines and was on the Dean's List in 1983. In addition she also appeared on the Academic Roll in 198 1 and 1984. She participates in the Society of Women Engineers, and this summer Beverly is working for North American Coal Corporation's Coteau Properties, outside of Beulah, North Dakota, as an Engineer's Assistant. [ ]DEE BRAY Montana College of Science and Technology Dee comes from a small ranch outside of Hall, Montana and is currently pursuing a degree in Mining Engineering at Montana Tech. This summer he is working for North American Coal where he was selected out of more than a dozen applicants for his position. As a side note, Dee's brother, Dean Bray, is also a Mining Engineer, a Montana Tech Grad, and works for Consol at the Glen Harold Mine in North Dakota.

Jan 1, 1985

By R. S. Morton

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

Jan 1, 1921

PRESIDENT LITTLEJOHN: The paper of Mr. Emrick will now be open for discussion for about twenty minutes. The meeting is now open for discussion. MR. EMRICK: There is some question that may have occurred to you at different times, that is how are you going to tell when the bits are properly made? A fairly good rule to go by is when the used bits come out of the mine, if half of them are bent and half of them are broken, the average is pretty good MR. GEO. B. PRYDE (Union Pacific Coal Company): I would like to ask Mr. Emrick if he has any figures as to the saving of Dower with the different styles of its. MR. EMRICK: I suppose you mean chisel point bits and pick point bits? MR. PRYDE: Yes. MR. EMRICK: So far as I have been able to learn, the only reason why chisel point bits are used is to prevent coring that might be done by the cutter chain. The pick point bit, of course, is the proper thing to use. It can be used when the position of the cutter links in the cutter chain is right. I do not know of any figures which give power consumption ratings on the use of pick point and chisel point bits, but there are tests and ratings, etc., which have been taken- which have been tested as against different bits, which have been given proper clearances against bits not having been given proper clearances, and they will run,-in their saving in power, they will run 20 to 25 per cent. MR. A. C. WATTS (Chief Engineer, Utah Fuel Company) : I would like to ask Mr. Emrick if he has any record showing the saving in power on using the alloy steel chisel bits. I know that several experiments have been made; I do not recall the figures now, but we had a very decided saving in power. MR. EMRICK: I haven't any of the records. Do you think that is because of the steel that has been used? MR. WATTS: Well, they were all sharpened by the same man and used in the same machine, and at the same shop. I do not know the composition. It is "Red Star" Vanadium that I had in mind. MR. EMRICK: I have not seen any records. Some companies are using the tool steel bits because they stand up a little bit better. MR. BENEDICT SHUBART (Secretary) : I was going to ask Mr. Emrick about that question. There is one company that does not recommend tempering the bits. They recommend using not exactly self-hardening steel, but one that is bard enough without quenching-they use 80-90-point car- bon but about a 70-point manganese, not exactly self-hardening steel, but they do not temper this at all. Will Mr. Emrick state if a steel of that kind could be worked in the bit sharpening machine that his company makes, as it

Jan 1, 1925

Briefly, the machine consists of a steel frame mounted on roller bearing wheels and axles, an electric motor, a fully enclosed speed reduction gear unit, a specially designed centrifugal pump driven through a friction clutch and silent chain, a mixture tank and agitators, and all necessary operating and control mechanism. The wheels are mounted on solid roller bearings made of special roller bearing steel, and are cast with deep chilled threads. The axles are of high carbon axle steel. A General Electric Company motor, of special design to exclude dirt and moisture, is used. It has an unusual overload capacity and a maximum torque at starting speed. Special arrangement can be also made for storage battery operation. The motor drives from one end, through a flexible coupling, to the speed reduction unit, and from the opposite end, through a similar coupling, to the pump clutch. The design of the flexible couplings is such that the drive is reversible. The speed reduction gears are enclosed in an oil and dust proof housing. All spur gears, as well as the main drive clutch, are made of steel forgings, with accurately cut teeth. An aluminum bronze worm wheel and special heat treated alloy steel worm provide the speed reduction for the traction drive. The worm shaft is mounted on Hyatt roller bearings and the thrust is taken in each direction by ball thrust bearings. The main drive shafts are of special alloy steel and operate in Hyatt roller bearings. The slow speed shafts run in extra large bronze bushings. Ample and constant lubrication is provided by splash from the gears running in oil. The Mudite pump is of special de- sign. A renewable wearing plate protects the pump casing from the natural wear of the mixture. The open runner is mounted on an extra large shaft which runs in a Hyatt roller bearing on the pump end and in Timken roller bearings on the outboard end. A special cage prevents water and grit from reaching the pump bearing. All thrust from the runner is taken on the Tim- ken bearings and these bearings also provide for the accurate and easy adjustment of the runner. The pump is driven by a silent chain, which operates on cut steel sprockets, from a friction clutch. The clutch is designed to secure long wearing qualities with minimum attention and its adjustment is easily effected. It is mounted on Hyatt roller bearings and the clutch drive shaft also runs in the same type of bearings. The pump discharges through a nozzle, which is adjustable, and controlled by the operator. The mixture tank is of approximately 650 gallons capacity. It is provided with a mixing well constructed of perforated plate screen to prevent large hard particles from getting into the valve or pump. The tank is filled through an opening in the top directly into the mixing well. On a shaft running longitudinally through the tank are arms so arranged that the mixture is thoroughly mixed and kept in continuous circulation from end to end. This shaft is driven from the speed reduction unit by a steel roller chain operating on cut sprockets. The traction drive is taken from the worm wheel shaft through steel roller chains of extra large size that run on cut steel split sprockets on both axles. An idler sprocket provides for easy chain adjustment. The axles are mounted in solid roller bearings in fully-enclosed dust proof housings, which support the frame through coil springs. These springs eliminate twisting strains on the frame on account of track irregularities and also relieve the working mechanism from road shocks. The speed reduction from the motor to the wheels is such that it gives an operating speed of approximately ninety to one hundred thirty feet per minute. The brakes are of the conventional shoe type and engage the wheels on both axles. They are operated by a hand wheel conveniently located and

Jan 1, 1925

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