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By F. A. Young

A description of the dry process coal cleaning plant which has been built and operated by St. Louis, Rocky Mountain & Pacific Company at their mine at Brilliant, New Mexico, should at first be a description of the special machinery which is used in this process. This equipment consists primarily of screens for sizing the coal into six different sizes all smaller than 1 ½ inch and the pneumatic machines for cleaning each size. These machines are patented and were manufactured by Sutton, Steele & Steele of Dallas, Texas, until a few months ago when all rights of sale were acquired by the American Coal Cleaning Corporation. These screens, a plan of which is now before you, are called anti-gravity screens because the coal travels up hill. The screens which we have at Brilliant are 3 feet wide and 7 feet 4 inches long. They consist of one upper deck which slopes upward in the direction of the flow of the coal, at an angle of 12 degrees. This deck is a wire mesh screen the size of which determines the size of oversize from that screen. Under this is a lower deck with a slope of 7 degrees. This is a solid bottom and is for advancing the undersize to the next screen. On account of the difference in pitch of these decks they are about 11 inches apart at the discharge end, which allows the oversize to be taken off at one or both sides and the undersize to fall only a few inches on to the following screen. This is perhaps the most valuable point in this patent as it allows any number of screens to be placed on a-level floor, tandem in a battery without elevating or rehandling the coal in any way. The length of the screens corresponds to the proper spacing of the cleaning tables which naturally operate on the floor below. I know of no other screen which can be operated in this way. The coal is caused to travel by a reciprocating motion. A shaft as shown near the center of the screen box and under it has an eccentric at each side of the screen with connecting rods attached near the rear of the screen box. The screen box is attached to the stationary under frame by means of cast iron plates extending full width across the screen box. These are placed at an angle as shown so that the forward motion of the eccentrics causes the screen box to rise as it moves forward and the backward motion drops the screen from under the coal thereby causing it to advance. The coal advancing over the screen cloth in this rolling or jumping motion causes very perfect sizing. It should be stated here that very accurate sizing is necessary for the success of the cleaning tables. The stroke is 1 inch and the speed 350 revolutions per minute. In describing the pneumatic cleaning table, I place before you a plan furnished by the makers. The basic principle is that if a film of coal one to two inches thick and all of nearly the same size pieces is placed on a flat perforated surface and a large volume of air passed through it, the lighter particles which are the clean coal will soon find their way to the top of the film, while the heavier particles, or waste, will remain on the bottom. The machine is built with a perforated deck about 4 feet square under which is an air chamber and air duct connecting with a fan which is part of the machine. The deck of the table has a reciprocating motion the same as the screens already described, which tends to advance the product up a slight slope which is adjustable. The coal is fed at one corner of the table as shown and the deck slopes also away from the feed and at right angles to the reciprocating motion. On top of the perforated deck are riffles about 2 inches apart and running parallel to the line of reciprocating motion. These riffles are about 1/2 inch high at the fan and feed side of the table and taper to nothing at the far side. When the coal is fed on to the table, the air through the perforations tends to raise it 'and roll it over these riffles down the slope toward the clean coal discharge. The heavier particles do not get over the riffles so rapidly and the reciprocating motion is constantly pushing them

Jan 1, 1923

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

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Jan 1, 1995

[Participating Scholarship Colleges and Universities 144 Andalex Resources, Inc 91 Behre Dolbear & Company, Inc 93 Canyon Fuel Company, LLC 92 Big Sky Coal Company 114 Commercial Testing & Engineering Company 96 Continental Conveyor & Equipment Co 97 Copper Mountain Resort 108 Cove Shoe Co., Inc 110, 111]

Jan 1, 1999

Presiding: Herman Van Houten, Senior Marketing Counselor, Joy Mfg. Company, Pittsburgh, Pa., and John A. Reeves, Vice President, Mid-Continent Coal &Coke Co., Carbondale, Colorado. The Keynote Speaker, Senator Jennings Randolph from West Virginia, was unable to come due to pressing business in Washington. A film presentation on Surface Mining and Reclamation, "Energy Bridge," Courtesy of Pittsburgh & Midway Coal Mining Company, Denver, Colorado, was shown and was prefaced by comments from James V. Fisher. "Advantages of Longwall Mining in Western Coal Production" was a paper presented by David W. Wisecarver, Supervisory Mining Engineer, U.S. Bureau of Mines, Denver, Colorado. Mr. Wisecarver graduated from Virginia Polytechnic Institute in 1949. After two years with International Harvester and two years in the U.S. Army, he joined the engineering staff on a Bureau of Mines underground mining operation in Virginia for eight years where he saw duties as mine surveyor, shift boss, and assistant maintenance superintendent.

Jan 1, 1977

(The following discussion took place on this screen lecture in the dark.) MR. SHUBART: Would you give us a little .explanation as to the operation of this machine and what you are doing with it? MR. TESCHER: There is a 20- horsepower motor, rheostat, crusher, and a fan mounted on one base plate and operating on one shaft. The fan is overhung on the shaft. The only bearings you have are the bearings on each side of the crusher and the motor hearings. On one side of the ma- chine there is an opening for feeding shale. The machine is operated at 1,200 revolution per minute and as the shale is pulverized, the fan automatically exhausts fine dust from the crusher from an opening in the top of the crusher. The machine pulverizes 3,000 pounds in eight hours, reducing the materid to one hundred mesh. The last ma- chine we put in has been operating continuously fifteen hours a day for the past sixty days, without repairs of any kind. PRESIDENT LITTLEJOHN: Where is the machine in operation? MR. TESCHER. At the Royal mine. We have used ordinary mining ma- chine cable in local movements of the machines. This has enabled us to have twenty-two locations throughout the mines. The mine is highly gaesous, and the machines had to be placed on intake air. MR. SHUBSRT: What type of crusher do you use? MR. TESCHER. A No. 16 Universal, operating at 1,200 revolution per minute. M. SHURART: What material do you feed to it? MR. TESCHER: We have shale three-quarters of a mile from the mine. In the winter months we have been troubled with moisture. We build a kiln and get this shale and load it into the kiln for drying and then place it into a pit car and take it into the mine. The material must be dry. We have also used slate in the mine and have had good success. The slate at the mine is fairly hard. I presume, however, that the slate will probably carry a high silica content. MR. SHUBART: Mr. Harrington claims that silica does not do the harm, as was formerly supposed. MR. TESCHER: There is still a question as to whether it is harmful or not. PRESIDENT LITTLEJOHN: Are there any of these machines in operation closer than Aguilar? MR. TESCHER: There is one at the Alamo mine. Mr. Quealy also purchased a couple of them for use at his Wyoming mines. PRESIDENT LITTLEJOHN: Are there any other questions you would like to ask Mr. Tescher regarding his rock dusting machine while it is on the table for discussion? MR. DALRYMPLE, SR.: How many men does it take to operate it? MR. TESCHER: One man operates the machine. Sometimes we put the

Jan 1, 1925

By R. Dawson Hall

R. DAWSON HALL (The Coal Age, New York City) : Mr. Chairman and gentlemen: I do not feel that I have anything in particular to say. I have not prepared anything for an occasion such as this. I just came from New York City, and as one man said to me today, "That is not any recommendation in particular." (Laughter.) In answer to your request for a few remarks of a timely character I would say: One of the possibilities in the Rocky Mountain Region coal mines is the use of steel arches, posts and straps. The timber of the region seems unusually subject to dry rot and does not last long, especially in those places as in southern Wyoming, where the mine atmosphere is likely to contain a large quantity of carbon dioxide. It is true that, in many mines, much care is taken to drive out this gas and to arrange that the timber will have the fresh air that will prolong its life, but despite such provision much timber is subjected to speedy rot. Steel has made rapid progress in England, Germany and France and is recognized as an economy, not an extravagance. Frequent replacement of rotting wood and removal of broken rock are a source of great waste, risk and inconvenience in operation that together spell great cost. The very dryness of the mines and the lack' of acid water are favorable to the use of steel where support of roof or sides is necessary.

Jan 1, 1932

By T. H. Butler

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

Jan 1, 1926

By Thomas Collier

MR. PRESIDENT AND CO-WORKERS IN THE COAL INDUSTRY: I was requested by our president to prepare a paper on Longwall Coal Mining, to be read before this honorable organization. There are three general systems of Longwall, Longwall advancing and Longwall retreating, and the Nottingham system which is worked in England and South Wales. In Fremont county, where I am employed, the Colorado Fuel and Iron Company are working their mines on the advancing system. The face is started generally from the bottom of the shaft or other mine opening, or, at the outside of the pillar left to support the shaft or slope-bottom and advances toward the boundary of coal area. As the roads in this system are maintained by pack walls, it is sometimes called gob-roads system, and by these means the mine is opened up rapidly and consequently early returns are secured from the capital invested. By this method, there is no expense for narrow work, and a minimum amount of timbering of the roads is required. Now what I call ideal Longwall work is where there is about eight inches of dirt mining-and four and one-half feet of coal, .and when the entries and rooms will gob themselves, so that there will be no rock or dirt to haul out to the surface. But this is not the case in the mine I am in charge of. The entries and rooms will not gob themselves, therefor we have to haul the rock and dirt to the surface, which runs up the cost of production. Now the ideal roof in Longwall is composed of tough elastic and pliable strata that yield gradually by bending when the coal is removed, and throwing a sufficient weight or roof pressure on the coal face to break the coal when the same has been mined or undercut. Timbering should be done systematically, the coal well spragged before the miner starts to undermine the coal. Cogs or cribs are alright in their place, but I am not a believer in crib in Longwall working because they are too strong for the roof and do not leave the roof to squeeze .down gradually and break the roof around the crib. Longwall work requires particular skill on the part of the miner, and a familiarity with the conditions affecting room and pillar work, and a good room and pillar mail may not be successful in. Longwall work. A good Longwall miner realizes more than any one else the importance of being regularly at his place every working day. A day lost causes his place to fall behind the others which makes his work harder, and his daily output is further reduced by the amount of small coal that is liable to result from the excessive pressure where the face falls behind. The bad results are also felt by the miner working on each side of such place, as the roof pressure is often insufficient and the coal does not break as well as when the face is kept in a uniform line.

Jan 1, 1921

By L. C. Clare

In a meeting of this kind where everyone present is connected with or engaged in coal mining, and where each one is present with the set purpose of learning new thoughts or ideas, the subject of the saving of life by any method in the industry is a vitally interesting and important one. On the cost per ton basis, it mounts to a formidable figure especially so during these days of depression and stagnant, or no business. But entirely outside of the human side of the question, to lose lives would cost more than saving them. Your insurance under haphazard safety measures would mount, loss of time due to accidents would impair efficiency among employees and the breaking of the morale of the staff, due to criticism of lax methods would cost more than an efficient safety program. Taking it for granted that most of you are looking at the question from the viewpoint of a yearly or five-year cost sheet, and that at this time you are doing all that can be done without bringing a ruinous cost upon your companies, I can offer only one suggestion: Raise the quality of your safety, or lower the cost. In this meeting, there should be no question of standing still or retreating in the quality of safety, so I will amend the suggestion with "Raise the quality and lower the cost." We have learned that when the coal beds were forming, nature sealed them in with a strata of mud that the ages have turned to shale, sealing them effectively against the deteriorating influences of the air. Mudite is carrying out nature's plan of coal preservation to the inside of the coal mine. Text books teach us that a large proportion of the vegetation that forms our present coal beds grow on what might be termed mud, later falling and being buried practically where it grew by mud, then on being subjected to heat, pressure and time, was changed to coal. The mud being subjected to the same three forces forms our present shale stratas. Now if nature saw fit to use this solidified mud as a preservative through countless centuries, isn't it reasonable to expect that occasional coatings on the ribs and roofs of entries and rooms will aid materially in preserving our coal and coal dust? Nature took mud and formed it into shale; mudite takes the shale, reduces it into dust, adds water and makes a mud, applies it to the ribs, roofs and floors of the mine in a thin coating

Jan 1, 1925

The Role of Partnerships ?Industry history ?Companies were their own kingdoms ?MSHA and NIOSH were out of touch and focused on enforcement with no direction ?Labor and management were constantly at odds with each other

Jan 1, 2002

Jan 1, 1992

Jan 1, 1990

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

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Jan 1, 1997

Jan 1, 1953

By Joseph Harrington

It is sufficiently correct to say that domestic solid fuel is universally hand fired and it is almost as correct to state that a very large proportion of hand-fired domestic fires are extremely inefficient and smoky. This is particularly true with raw bituminous coal for the fuel. The smokeless and efficient firing of domestic coal affords one of the most difficult problems confronting the combustion engineer. This is due to the universally constricted combustion space in the domestic furnace, the complete ignorance regarding the laws of combustion on the part of the average person, and the fact that the laws of efficient combustion are almost completely nullified under these conditions. It is well to familiarize ones self with these laws. These are: 1. The gradual introduction of the fuel to the furnace. 2. The admission and mixing of the right quantity of air with the coal gases. 3. A temperature high enough to permit complete combustion, and 4. A furnace space of volume sufficient to permit of the combustion gases and the oxygen getting together within the confines of the furnace. Even a casual inspection of the domestic heater will show that none of these essential things are present in proper degree, and this is the reason why the problem of domestic firing presents such difficulties. I have analyzed these conditions in a paper published by the Black Diamond, and which has already had wide distribution, so that I will not repeat the rather lengthy discussion in this paper. A survey of the entire field indicates very clearly that a reversal of existing methods and equipment must be had before any real improvement can be expected. It is my firm belief that in this instance above all others it is necessary to build the efficiency and smokelessness into the equipment in such a manner that its performance will be entirely independent of both skill and interest on the part of the operative. To attempt to educate every man, woman and child who periodically throws coal into a domestic furnace would be literally impossible. Much can be done, however, if we could teach the householder the simple essentials of alternate firing, which I have explained at length in the above mentioned paper. This would go a long way toward making the domestic furnace problem more satisfactory, as well as efficient and smokeless. Many will argue, and with good reason, that the domestic fuel should be prepared coke and with this I agree up to the limit imposed by the practical considerations of quantity production, price and the possibility of marketing the by-products. It will be obvious that if enough raw coal should be processed to provide all of the required domestic fuel that the amount of by-products recovered during the coking process would be so great that there would be little or no market at any price which would justify the manufacture of coke. If the by-products were wasted they would not only be a tremendous economic loss, but the price charged for the coke would probably be so high that the market would be limited, and this would defeat the very idea of the whole thing. Much can be done, however, in advancing the use of coke, but I believe that much more extensive and careful experimentization should be had in order to determine the right size and quality of coke for the various domestic furnaces. If coke were to be developed for extensive domestic consumption it is more than probable that the coking process should and could be stopped at a point where the volatile content of the coke would be sufficiently high to permit of prompt ignition and combustion in low draft installations. If the volatile content were from five to ten per cent a very different kind of coke would be produced from that which is now produced with perhaps one per cent of volatile. A skillful manipulation of this feature would make coke adaptable and satis-

Jan 1, 1925

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

By Jerry M. Eyster

The Bush Administration is committed to reducing emissions from existing power plants Candidate George W. Bush said: The key to reducing emissions from older power plants on the federal level is to cap emissions on a level that makes sense?. And harness the power of the market place and provide economic incentives to produce better environmental results. I would want to make sure that any program we pursue does not result in excessive and unnecessary increases in electric bills.

Jan 1, 2002

President Schloss called the third session of the fifty-eighth annual meeting of the Rocky Mountain Coal Mining Institute to order at 9:30 a.m. and introduced James Westfield, Assistant Director, Health and Safety, U. S. Bureau of Mines, Washington, D. C., who presided over the session. First speaker of the session was S. L. Jewell, Vice President, Peabody Coal Company, St. Louis, Missouri, who spoke on "Our Three Main Routes From Here." (Biographical sketch of Mr. Jewell, see index.) (For the printed text of Mr. Jewell's paper see index.) Mr. Westfield introduced Marling J. Ankeny, Director, U. S. Bureau of Mines, Washington, D. C., who served as moderator on the panel, "How Do We Go From Here in Safety?"

Jan 1, 1962