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MR. STOUT: The picture shows the plan of the "V"-system as worked at Berwind mine, in a small strip of coal adjacent to the 4th right entry. The dotted line (indicating) show the position of the break rows as set for each of the three consecutive breaks. In two cases the break rows failed to function properly and as a result, the roof caved along the points of the "V's" as well as back along the faces a short distance. This affected the ventilation to a certain extent, but was remedied immediately by cutting through the points near the cave and setting additional timbers. At the present time we are putting in the break row of heavy red spruce props, making the row straight instead of curved as is shown in the picture; in this way we believe we can better control the breaks. The three "V" entries were driven up 14 feet wide, for a distance of 260 feet without cross-cuts. A very neat and substantial line brattice was carried up each entry as the places advanced. The principal factors in determining the success of this system are ventilation, roof control, and transportation. We are well pleased with the results from these three "V" places and now have four other places, about 500 feet to the west of these, driving at the present time in which we hope to get still better results. A MEMBER: What centers did you use there? MR. STOUT: We used 70 feet. This may be increased or decreased according to local conditions. MR. F. W. WHITESIDE (Chief Engineer, Victor-American Fuel Co.) Will you please describe roughly how your cars are handled? MR. STOUT: Cars are brought from the parting and pushed up along the faces by a storage battery locomotive. The faces are about 70 feet long and we found that five or six cars can be loaded and transported very conveniently. It is important to get a quick exchange of cars, and in this way we were able to keep the shovelers busy at all times. A MEMBER: What is the grade in your "V" entries? MR. STOUT: Five per cent in favor of the loaded trip. A MEMBER: What is the angle of your "V" faces? MR. STOUT: The angle at the throat is 45 degrees. MR. SAMUEL ANDREWS: In what direction does the air travel? MR. STOUT: The air travels down the dip entries and is deflected up the first "V" entry, and travels along the points, and returns down the last entry. There is no more difficulty in ventilating "V" faces than in ventilating rooms, providing the points are kept open. A MEMBER: What amount of air do you have in that section? MR. KAISER (Superintendent, Berwind Mine): Eighteen thousand cubic feet per minute. MR. ANDREWS: It is necessary, Mr. Stout, to brattice these places?

Jan 1, 1925

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

BENEDICT SHUBART: I am rather surprised at one statement of Mr. McKeehan, that he found it satisfactory to bond only one track. It has always been my idea of good practice to bond both tracks and cross bond frequently, so that in case of any break in the bonding of one track, which frequently occurs, there will be no interruption in the circuit.

Jan 1, 1923

By David A. Zegeer

Since 1980, more than 40 miners have lost their lives by being trapped and suffocating in stock-piles, bins, silos, and similar facilities. Mine Safety and Health Administration (MSHA) is concerned about these accidents, most of which could be prevented if management and miners appreciated the hazard. In February 1986, the coal industry had a suffocation accident that drew national attention. A group of engineers were standing on a coal stockpile. It gave way under their feet. Five of the engineers were buried in the coal and suffocated. As with all fatal accidents, MSHA investigated the cause of this tragedy. I also asked my staff to look into the history of similar accidents. I found out it is rare to have multiple fatalities due to suffocation in material. But, over the years, there has been a long series of individual fatalities from this type of accident. Here are some examples. In Oct. 1985, a coal mine employee in Virginia entered a hopper to collect a coal sample. The feeders were started while he was standing in the hopper. He sank into the coal and suffocated. In Sept. 1985, an employee at a Texas sand company climbed onto a surge pile, to check a problem with sand flow. When other employees found him, the sand had swallowed him. Only his face and one hand were showing. Though the victim's face was clear of the sand, he suffocated before rescuers could free him. Many people do not realize you can suffocate in this kind of situation, though your head is free. Every time you exhale, the material has room to shift and press harder against your chest. Then you have less room to inhale. If this goes on long enough, it gets to the point where you cannot inhale at all. That is what happened to the victim in this accident. In May 1985, a plant operator at a Wisconsin sand and gravel operation purposely slid into the drawhole of a surge pile. He tried to break up large rocks that were clogging the drawpoint. Material piled on the side of the surge pile slid down and buried him. The operator was wearing a safety belt and line. But he was covered by 3 to 3.7 m (10 to 12 ft) of material and could not be pulled free. This incident illustrates another point. A safety line can help. But it is not enough. Workers should never put themselves in a position where loose material can fall on them from above. In Jan. 1985, a young Utah coal miner was waiting for a ride home from a co-worker whose job was at the tipple. A jam developed in the coal bin. The men could not clear the jam from the outside. So the young miner jumped into the bin. He started digging with a shovel at the toe of the coal pile. It caved in on him and he suffocated. The young miner had only three months of mining experience. He had not been trained for work around the coal bin. Since 1980, 16 coal miners and 26 nonmetal miners have lost their lives in loose-material suffocation accidents. Suffocation accidents occur in many areas around mines - bins, hoppers, stockpiles, surge piles, and silos, among others. One recent accident occurred at a surface coal mine in Illinois. The victim was walking over an area that had been drilled and blasted the week before. He fell into a void that had been crusted over with earth. He too suffocated. And many materials have been involved in suffocation accidentscoal, crushed stone, sand, salt, different kinds of ore, ammonium nitrate pellets used in blasting, and a powdery byproduct of iron ore milling called calcine. In addition to fatal accidents, there are near misses. We do not know how many. Most of them are not reported. A person who gets trapped in material, but is rescued, is usually unhurt. MSHA sometimes hears about these accidents by chance, or because they are reported in the local media. We do know that near misses are happening far more often

Jan 1, 1987

By Brandon Buschmeier, Frederic Masse

"Inclusions are a type of ground improvement that provide an improvement of a soil mass by insertion of a material with better characteristics than the surrounding soils. There are primarily two types of inclusions: “Soft” inclusions which are constructed of granular material (Stone Columns, Rammed Aggregate Piers, VibroPiers...), and “rigid” inclusions which are constructed of grout inserted with or without pressure (VibroConcrete Columns, Controlled Modulus Columns, Soil Mixing Columns).While the central principle of the inclusions is similar (i.e., overall improvement of characteristics of the soil mass below the structure), the load transfer mechanism is radically different for each technique. Therefore, the applicable design methodology is specific to the type of inclusions and there exists no universal method of design which spans across all inclusions.This paper will present an in-depth comparison between the standard design methods used for “soft” granular-type inclusions (Priebe modified, Balaam & Booker, Goughnour & Bayuk...) and the methods used for “rigid” inclusions which mainly rely on finite element analysis. The paper will explain why the design for soft inclusion methods cannot be applied to rigid inclusions and vice-versa. Each design method will be reviewed in detail to better emphasize its limitations and advantages.Two case histories will also be presented; one for each type of inclusions in order to illustrate the concepts developed in the first part of the paper.1 INTRODUCTION1.1 GENERAL OVERVIEW OF GROUND IMPROVEMENT WITH INCLUSIONSThe use of ground improvement methods to provide the appropriate amount of foundation support is a growing and constantly evolving industry. Traditional structural foundation methods including ‘shallow’ and ‘deep’ foundations do not adequately address the wide range of settlement tolerances, soil conditions, and loading considerations inherent to each unique potential project. In some instances, ‘shallow’ foundation solutions are simply not feasible due to soil and loading constraints. Furthermore, ‘deep’ foundation solutions are used to ‘bridge’ the soft compressible soils, ensuring that the entirety of the load in the structure is transmitted through individual elements into competent layers below the ground surface (bedrock, dense residual soils). Highly concentrated structural loads are transferred into the individual elements by means of direct contact requiring the use of structurally rigid surficial components (structural slabs, grade beams, and pile caps).Ground improvement bridges the gap between these two traditional methods, offering adequate foundation support while using more costeffective techniques and design methodologies. Inclusions are a type of ground improvement used to provide a reinforcement of the soil mass through the vertical insertion of a material with better characteristics than the surrounding soils. Much like deep foundations, inclusions are installed through soil layers with high compressibility and/or low bearing capacity and terminated in a suitable bearing stratum. However, unlike deep foundations, ground improvement inclusions rely on a distribution of load between the soil and the inclusions. By doing so, some of the structural load is applied directly to the soil in a proportion equal to its bearing capacity and compressibility limits, while the rest of the load is shed into the vertical inclusions down to the bearing stratum. Load sharing is a critical aspect in the performance and design of the various ground improvement methods."

Jan 1, 2015

Remarks Of Mr. Robert W. Hunt, General Superintendent, Albany And Rensselaer Iron And Steel Company., Troy N. Y. - In discussing Dr. Dudley's two most interesting papers, I feel a natural hesitancy in disagreeing with conclusions formed after such careful and conscientious work. But I think he has made his deductions from too meagre premises. The analyses of but twenty-five samples are entirely too few to justify the establishment of so important a formula. When we consider that he indirectly proposes to regulate an interest amounting, even at the present low prices, to over $20,000,000 per annum, we may well hesitate before accepting a formula based upon the chemical and physical analyses of but twenty-five steel rails. Dr. Dudley touches the keynote in referring to the proposed labors of the Government Test Commission. They based their hopes of attaining success upon the chemical and physical analyses of a very large number of samples, and in the only branch of investigation which the short-sighted policy of Congress has allowed them to complete, i.e., chain cables, we find that a dozen, twenty-five or one hundred tests gave no satisfactory results. It was only after many hundreds that they were enabled to draw conclusions. There are so many circumstances bearing upon the life of a rail, that the task of extracting a correct result seems herculean. I presume I am right in stating that in our Northern latitudes early winter and spring months witness the breaking of the greatest number of rails, thus seeming to prove that an unstable road-bed has much to answer for. Then, again, broken and flattened wheels must be taken into account, but I am convinced that more rails have been broken by the treatment which they received before leaving the rolling-mill * The remarks of the participants in this debate have been written out by the speakers, and are here given without any attempt to retain the order of the dis¬cussion. While the report does not, therefore, preserve the vigor and spontaneity of the debate, it is believed that it gains in value by giving the matured views of the speakers. The continuation of this discussion at the Pittsburgh Meeting, May, 1879 (beginning with remarks of Mr. Cloud on page 401), is appended for convenience of reference.-T. M. D., Sec'y

Jan 1, 1879

By Hickling G.

Discussion at the Manchester Geological and Mining Society's general meeting held in Manchester, February 8th 1916, with Mr. Leonard R. Fletcher, President, in the chair, of papers previously published in Trans. Inst. Min. Engrs.,1915, vol. L, p.322 and p.328. Included are a written contribution by Ollerenshaw W. and oral discussion by the author, Gerrard J., Paton J.D., Smith S.A., Stephenson H., Dixon H.O., Pickup W., Fletcher L.R. and Atherton H.S.

Dec 1, 1916

CONCLUSIONS: Our experience, where we attempt to remove a continuous face with a seam more than six and one-half feet in thickness, has been rather disastrous. We have been able to open up faces and retreat for a distance of 75 to 100 feet in this particular character of coal, but after the supporting timbers have been removed for the second or third time we have found that the roof has a tendency to ride over the props and break off at the face of the coal support. However, where our coal is below six and one-half feet in thickness we have had very good success in handling the roof and breaking it off systematically with our break line of props, which are usually from 12 to 15 feet from the face of the coal. Our practice in to set props at about two-foot intervals in each direction and remove two sets of props, at the same time two additional sets are placed along the coal face. At all times we are very insistent that all props be removed from the gob and that entire coal be taken out so that it is possible for the roof to break freely and all come down, not having any supporting pillars in the gob. The conclusion of our experiments to date is that if all the supports beyond the breaking line of props are taken out as the long face retreats and the closer the breaking line of props is kept to the face the better the results will be. We have never felt it safe to have less than four rows of props to protect the machinery and men working along the coal face. We feel that the time element as to the rapidity with which these faces are advanced or retreated, is of vast importance, but to date have not had an opportunity or experience enough to reach any conclusion as to what time element is proper here with us. We feel that the crushing strength of the overlying strata will govern this to a large extent, and as ours varies considerably, it is going to he very difficult for us to reach a definite conclusion. My opinion is, that conditions may be such that rather than have a short face and retreat rapidly, it will be found that a longer facewith a slower retreat will work out better. Such a condition might give the overlying strata time to settle. The caving of roof or of control of this caving, with us, is quite closely associated with the ventilation. We find that the places where the strata overlying the coal are composed of shale, that the effect of the air on this is of very great importance. It is our endeavor, at all times, not only to remove obnoxious gases, but to keep a current of fresh air moving along the face and, of course, a portion of this travels over the gob and comes in contact with the roof and overlying strata. This, we find, helps materially in keeping the roof on the move. As it is our practice to keep water for sprinkling purposes at all places, we also use this water to keep the roof wet back in the gob. The effect of water on the shale is to cause it to disintegrate quite rapidly. MR. HOLMAN (Concluding): If there are any questions about this, I will be glad to answer them. I have some prints and also some pictures of the scraper loader and the shaking conveyors (distributes.) PRESIDENT MOSES: We wish to thank you, Mr. Holman, and also wish that you would thank Mr. Dupont for his paper. Are there any discussions? Do you wish to ask Mr. Holman any questions? (No response.) PRESIDENT MOSES: Mr. Holman, I would like to ask you how you take the photographs; were they taken by flashlight, or were globes used, or how were they taken, in a gaseous mine? MR. HOLMAN: Our mines being gaseous, we do not use the ordinary flashlight for taking underground photographs, but we have had considerable success, I think, with underground pictures by means of electric lights. We use 250 watt globes. We have six of these rigged up with tin reflectors, 18 inches in diameter, on standards, and we carry two or three hundred feet of wire connected with these six lights, and they can be turned on in the room where we take the photograph, by means of this extra wire. We set the kodak up and arrange the picture and take a long time-exposure. We usually take an

Jan 1, 1926

MR. SHUBART: Mr. Miller's paper mentioned the two processes that seemed to be a success, the Smith process and the Piron process. I suppose the main difference is this, that Smith's process is to furnish domestic fuel and the by-products while the Piron process that Ford is installing is for fuel for power plants. I would like to ask Mr. Miller something about the commercial cost of the process. With the briquette you must make it cheap enough to sell. What are the commercial possibilities of Smith's briquette? MR. MILLER: It is pretty hard to say what the cost would be at this time, owing to the fact that slack has advanced double, or even more at the time I was in New York with the plant, but at that time it was costing $1.10 for the operation. You can add to that, of course, the cost of the coke. One dollar and ten cents was the entire cost of plant operation. It takes about one and one-half tons of coal to make a ton of briquettes. One dollar and ten cents takes care of all the material, cost, labor, handling, etc. Labor was much cheaper then. I would say it would cost about $2.20 now. The cost of coal is what you can buy it for on the market. I don't think, however, that the carbocoal process will ever meet with any great favor for the simple reason that it is really a prepared fancy fuel. It is going to be nice for people in offices where they want a grate or for families where they want a nice clean fuel. It leaves no stain on the fingers, no odor to it. It seems in carbonizing coal we change the carbon molecule. For instance, we are all familiar with the diamond. It is carbon, yet it requires a tremendous heat to burn a common little diamond. But you can set a piece of charcoal afire, which is also carbon, with a match. The molecular form has been changed in carbonizing coal, i. e., it is larger. Carbocoal will fire very readily, it can be started with a piece' of paper. I think the Piron process will be the process, i. e., to simply take out the tars and light oils, then fire direct-have the distillate plants right on the job. CHAIR: Can Mr. Shubart tell us something of the mechanical part of the Piron process? MR. SHUBART: The Piron process is of interest because Mr. Ford is taking it up. He has made so few mechanical mistakes it makes us feel that it is a success. Piron is a chemist of high accomplishment and reputation. The thing about the proces is its simplicity. Mr. Smith's is a very elaborate process, but Piron has gotten around all that. Piron feeds the raw coal in at about one-half inch mesh or smaller. He feeds it into a retort about 55 feet long, 16 feet wide over all. He has a hearth about 6 feet wide and the length of the retort. The base of the hearth that carries the coal is a conveyor, a flat cast iron conveyor, a very massive affair, very accurately made, so that there is no loss of coal. Between the upper and lower strands of the ' conveyor is a bath of molten lead which gives an accurate control of temperature. For best results he must have temperature of not under 800 F., not over 1,300 degrees F., about 1,100 or 1,200 F. seems to be ideal for getting greatest yield of oils and the best tars and other by-products. This lead bath has a system of flues running through it that

Jan 1, 1923

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

Jan 1, 1924

PRESIDENT PRYDE: I am sure we have all listened with interest to the presentation of this subject. Anything that promises economy in coal mining today is welcomed by all of us. We will now have a discussion on this paper. If any of you gentlemen want to ask any questions, you may do so. I think we will develop something of interest and along the lines of economy. That is the first consideration of a coal mining man. MR. H. D. RANDALL: It is an interesting fact that in manufacturing we find the greatest economy results from giving a man the simplest possible act to perform, while there is nothing too complicated for a machine. If we want to put up a set screw we find it cheaper to let one man set it up and the other screw it in. The maximum economy is what we are after. Similarly, one of the points of greatest interest which Mr. Ickis has emphasized, is that this automatic equipment not merely dispenses with a manual operator, but also performs certain functions which the operator cannot do. It provides an inherent protection to the apparatus and service not possible under manual operation. We very rarely have cases of failure with these automatic equipments, .and consequently have the advantage not only of having eliminated the operator's salary, but also his mistakes. We have had a large number of these equipments in use for several years, so that their practicality is now thoroughly proven, and the trend of practice now indicates that the automatic idea will be further extended and will become universal for such classes of service. MR. D. C. McKEEHAN (Union Pacific Coal Company) : My notion of an automatic sub-station is one that does not necessarily require new equipment beyond the control equipment; so that any of you that are interested in it can take up with the manufacturers and find out how much it would cost to change any equipment. The greatest point I think is the fact it eliminates the several nationalities from operating the set, either on day shift or night shift. They can so lock the control as to make it impossible for anyone to start or stop it, except the one who has the authority. Another point I do not believe was brought out very clearly: It would be particularly advantageous to people who buy power, and if you could have several sets in parallel, it would allow you to start the shift with one set and cut in the additional sets as the shift progresses. There are various operations that stop at the end of each shift, and-one or two or three sets can be cut out, leaving the load on one set, providing the size of the copper is sufficient to supply all the points of the mine. Another point I want to bring out: In case you have quite a number of sets distributed along transmission line, the switch trips, the operation restores the service, and you may have several hundred-or in case with us, we would have several thousand-K. V. A. of Motor Generator Sets and Rotaries, that would be starting at once, and the switch would automatically trip out again. MR. RANDALL: Another form of control was described as the so-called supervisory control. This control could be started up so the starting would not be synchronous, but could be spread out over a sequence. MR. McKEEHAN: I think that is rather a theoretical consideration for coal miners. They are standing at the controller ready to shut it off unless there is some selective method of starting various sets- MR. RANDALL: I had in mind this supervisory control, one man, a central operator who would determine which station should start and he would take time enough to have his load come on gradually. He would not permit all the installations to come on simultaneously, but come on in succession: MR. McKEEHAN: You misunderstand me. Suppose we had the main switch at Rock Springs, which supplies several camps, and there are several

Jan 1, 1924

Secretary's Apology: Although every effort was made to secure efficient stenographers, the railroad conditions at the time made it impossible to get stenographers from Salt Lake City. Practically all of the discussion was therefore lost, and the Secretary's apologies are offered to those whose names and remarks we are unable to record. 'We are indebted to R. Dawson Hall of Coal Age for what we have been able to print. The question was asked why belt conveyors are not more generally used. BENEDICT SHUBART: Belt conveyors lack the ruggedness of metal conveyors and require more accurate alignment. They are much used in England though comparatively scarce here. The H. C. Frick Company's belt installation at Colonial mine is an unusual installation for unusual purposes. It is hardly main haulage, but is more comparable to railroad transportation. The belts are in long sections,, nine hundred to twenty-three hundred feet, there are no particular grades, only two turns, and the immense tonnage handled justifies a quality of installation that at this day would not prove economical in most mines. EUGENE McAULIFFE, Union Pacific Coal Co., Omaha: Was much impressed on learning at the American Mining Congress that the Hudson Coal Company had mined last year 1,500.000 tons of coal from a 36-inch bed and had transported this coal to the mine cars by scrapers and conveyors. He did not believe that because one or two percent of the men around the mines were opposed to loading machines, that it should be said that the mine workers were inimical to such labor saving means. He believes that when duly explained to them they could see the advantages of the equipment offered and would be friendly to its introduction. The Sheridan-Wyoming Coal Company at Sheridan have eight Goodman Hydraulic loaders in operation in rooms .with Joy loaders driving the headings. It is not possible for the mines which had to pay high wages to compete with those whose wage scales were lower unless by the introduction of loading machines. He received a letter from Dr. L. E. Young of St. Louis, general manager of the Union Collieries Company, that his two Goodman Hydraulic machines were loading an average of three hundred tons each daily. THE SECRETARY: H. N. Taylor, president, Sheridan-Wyoming Coal Company, said Mr. Green of the American Federation of Labor told him he would have no trouble with Union Labor, and, if any local disturbances were created, they would be stopped. The Union nationally is with the introduction of labor saving equipment. J. B. FORRESTER, General Superintendent. United States Fuel Company, Hiawatha. In his opinion metal conveyors are preferred because they can be lengthened and shortened at pleasure, and so can be operated with greater flexibility than belt conveyors. W. C. HOLMAN, Chief Engineer. Phelps Dodge Corp: The Phelps Dodge Corporation have two Jeffrey belt conveyors in tandem which obviates brushing where the coal is low. MR. E. O. WIEDERANDERS, Jeffrey Mfg. Co.: Says he has seen belt conveyors in use in England and is much taken with the idea. MR. WM. MOORHEAD, Phelps Dodge Corp.: Our conveyors are in twenty-foot sections, each with a motor. Three of them tandem make a sixty-foot face. GENERAL: There was discussion regarding the size of the coal produced by conveyors. It was said that when the Gunn-Quealy Company started their operations, the coal was very large, but now there is not so much care taken to produce large coal as the market is now demanding smaller coal. The Secretary said that the use of conveyors at the Kemmerer Coal Company's mine had almost doubled the percentage of lump coal. Mr. McAuliffe questioned

Jan 1, 1925

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

By Dickinson C.

Discussion at the The Midland Counties Institution of Engineers' general meeting held in Nottingham on 6th May 1916, on the paper published in Trans. I.Min.E., vol.XLVIII, 1914, p.400, included brief oral contributions by Bragge G.S. and Hepplewhite W.H. with the author's responses regarding leakage and boring of cement into the coal

Dec 1, 1916

Frank Clemes Smith, Deadwood, 8. D. (communication to the Secretary): The reading of Mr. Chance's interesting paper suggests a few ideas relative to his discussion of certain Black Hills gold-ores. Mr. Chance refers to his examination, in 1897, of " the (Carboniferous) limestone plateau-country which encircles the central area of the Black Hills," and says that " it had been generally assumed that the mineralization of this formation was confined to the northern area;" further, that he "found, however, a general mineralization, extending in zones or belts throughout the region," and that the ores, being more or less specially

Jan 1, 1900

John Birkinbine, Philadelphia, Pa.: We have in the Institute two Dudleys—Dr. Charles B. Dudley, who has so thoroughly studied the chemical composition and physical behavior of rail-steel, and Dr. P. H. Dudley, whose investigations and

Jan 1, 1900

Discussion at the Midland Institute of Mining, Civil, and Mechanical Engineers' general meeting held in Leeds, March 21st, 1916, with T. Beach, vice-president, in the chair, of a paper published in Trans. Inst. Min. Engrs., 1916, vol. L., page 509, comprised a written contribution by O'Shea L.T.

Dec 1, 1916

Marius R. Campbell, Washington, D. C. (Communication to the Secretary): Having spent considerable time in a systematic study of this field,'both as regards the details of its structure and stratigraphy and the broader question of its relation to the Appalachian basin, I wish to add a word concerning the correlations made by Mr. Hodge in his paper. From A commercial standpoint, the question of correlation, even along the strike, is of little or no importance, for the variability is such that each opening should be tested individually, regardless of the horizon at which it appears; but these correlations assume an entirely different aspect when their scientific bearing is considered; they then become of vital importance, and, before being accepted, should be subjected to the most rigid scrutiny and severe tests. Mr. Hedge states positively that the Imboden seam of coal is equivalent to the Elkhorn coal of Pike and Letcher counties, Kentucky. In the writer's opinion, such equivalency is, at the utmost, only a possibility. This correlation has been generally adopted by the geologists of the Kentucky Geological Survey, but the writer has been unable to find on what grounds they base the statement. The evidence of identity seems to be in the character of the coal, as both seams furnish fine coking coal; also, in the similarity of the interval between them aid the " Bee Rock," or top of the great conglomerate. It is probably an easy matter to determine the thickness of this interval on Elkhorn creek, and we will assume that the measure of 300 to 350 feet is correct. In the Big Stone Gap field, the question of measuring the interval between the Imboden and the " Bee Rock " is exceedingly difficult. The line of outcrop of this mass of strata is along the northern base of Stone mountain, and, in the uprising of the great arch, the strata on its flanks have been thrown into many minor folds, and, in places, have been broken by local faults. This complicated structure, together with the absence of ally well-marked stratum, renders it exceedingly difficult to obtain a correct measure of the intervening sandstones and shales. The interval of 300 to 350 feet, assigned by Mr. Hodge, is mani-

Jan 1, 1893

By Black J.

Further discussion at the The Midland Counties Institution of Engineers' general meeting held in Nottingham on 6th May 1916, on the paper published in Trans. I.Min.E., vol.L, 1915, p.449, included brief oral contributions by Bragge G.S., Hepplewhite W.H. and Binns G.J.

Dec 1, 1916

Discussion continuing that published in Trans.I.MIn.E ., 1915, vol.L, p.449 and 1916, vol.LI, p.166, included contributions by Smith W., McLaren R., Gibson J., McCreath W., Sneddon J.B., Kirkpatrick J. and Mowat D.M. and a written response by Black J.N.

Dec 1, 1916