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By H. F. Nash

Coal is the basic necessity of our present-day civilization, and those engaged in the industry, whether miner, day-man, pit boss, tipple boss, superintendent, salesman or operator, have a direct responsibility to the public at large. Our country is blessed with a great supply of Bituminous coal, upon which it must largely depend for its industrial prosperity. Anthracite coal, in its relation to our economic situation, is a small factor, as its ratio of production to Bituminous coal is only about one-sixth. However, within the last ten years, electricity and oil have largely displaced the use of coal in industry, so that the use of Bituminous coal is decreasing, relatively, and the potential production of Bituminous coal has largely increased since the war. High wage scales and high freight rates make the delivered price of coal to the consumer so out of proportion to the cost of electricity and oil -and strikes make the supply of coal so uncertain-that industry is rapidly turning to electricity and oil. The energy in a ton of coal can be transported, by electric current, a distance of 250 miles for 78% of what it costs to ship the coal in bulk, by rail, in the East-and, for about 60% of what it costs in our section of the country. The use of fuel oil, distillate and gasoline, in industry, has increased by leaps and bounds. Especially was this noticeable during the strike this year, as the large packing plants in Kansas City, Omaha and Sioux City (that formerly used nothing but coal) are now practically all using oil. This also supplies to other industrial plants throughout our territory in Texas, Oklahoma, Kansas and Nebraska. Many railroads are using oil, as are also the smelters, cement plants, etc., etc. Ten years ago, 100% of the threshing in the state of Kansas was done with coal-today not over 25% of it is done through that means-and so it goes all along the line. The use of our coal is being yearly more restricted in industry. In the case of domestic consumption, the circle is also ever decreasing.' In small towns and on farms, kerosene, gasoline and wood are largely utilized for cooking. For the past four years, along any country road, it is a common occurrence to hear a buzz-saw cutting old fence posts or timbers taken from creek bottoms. Many thousands of tons of coal are displaced each year through the use of corn and cobs. In larger towns, gas plants have been installed, and many housewives use gas-in communities contiguous to natural gas, that is used for industrial and domestic purposes. The time has gone when industrial and domestic consumers or dealers are satisfied to buy anything that is black-competition among the coal-producing states is keen, and will become more so. Eastern and southern fields are turning out splendidly prepared coals of high quality, and with their lower freight rates to competitive territory, will entirely nullify the use. of our Western coal unless-

Jan 1, 1922

The seventh Annual RMCMI Mine Rescue Evaluation was held during the 1998 Institute convention at the Silvertree Hotel, in Snowmass Village, Colorado. The Mine Rescue committee, co-chaired by Becki Boam and Elliott Tsosie, is one of 18 committees of the Institute. In 1998 a record number of 10 teams participated in the program. The teams were from the four western states of Montana, New Mexico, Texas and Wyoming and were comprised of about eight members each. Teams participating were BHP-La Plata Mine, BHP-Navajo Mine, BHP-San Juan Mine, all from Farmington, New Mexico; Bridger Coal Company, Rock Springs, Wyoming; General Chemical, Green River, Wyoming; Jacobs Ranch Mine, Gillette, Wyoming; Powder River Coal Company-North Antelope/Rochelle, Gillette, Wyoming; Sabine Mining, Hallsville, Texas; Solvay Minerals, Green River Wyoming, and Western Energy-Colstrip, Montana. The professional evaluators provided challenging scenarios for over 90 participants and many observers. The evaluators were: Art Saenz and Tom Bass of Western Environmental Associates, Keith Mitchell and Jim Jennings of Emergency Services Detail; Mary Bailey of Mary Bailey Associates; and John Peleaux of Innovative Access. Teams are not given advance warning of what the problem will entail. They are provided the necessary details when they arrive at the scenario location and work to resolve the problem in an effective and efficient manner. [ ] Seven participants made up each team with an . eighth member as an alternate. Team trainers and other mine personnel traveled with the team from scenario to scenario providing support and encouragement. The teams were presented with four scenarios each day, involving High Angle Rescue, Low Angle Rescue/Medical, Hazmat, and Confined Space. All of the victims, except for one, were provided through the cooperative efforts of the Snowmass Fire Department, who also assisted with providing several evaluators. Snowmass Fire Department is to be commended for providing over 20 victims/evaluators each day to facilitate the evaluations. Training sessions were held Friday afternoon and Saturday evening to help the teams prepare for the scenarios. A swap meet was held Friday evening for teams to trade hats, shirts, belt buckles, stickers, etc. All mine rescue participants and spouses and registered families attended the Bar-B-Q on Sunday evening followed by an adult dance. [ ] Front row: Ray Blaisdell, Solvay; Gary Rasmussen, General Chemical; Spencer Thompson, Sabine; Jack Ervin, Western Energy. Back Row: Ken Kellywood, BHP Navajo; Jonathan Sorrell, BHP LaPlata; Elton Stanton, Jacobs Ranch; Travis Roy, Powder River Coal; Ron Neff, BHP San Juan; Steve Whaley, Bridger. Sponsors who contributed to the 1998 program financially were: Blue Mountain Energy, (Deserado Mine); Flanders Electric Motor Service, Inc.; Rocky Mountain Electric Motors, L.S.; and Western Environmental Associates. Glass trophy cups, with an etching of a Mine Rescue figure and the RMCMI Logo on cherry wood bases, were presented to the 10 team captains at the Monday Mine Rescue Awards Breakfast. Eight of the ten teams had a proficiency level of 3 and 2 teams achieved a proficiency level of 2.

Jan 1, 1998

PRESIDENT LITTLEJOHN: I have every reason to know Mr. Pryde was carrying out some experiment a while ago in some of his mines. He and I had a little correspondence on the question, and I think he may have a word or two to say about it. He has not been on his feet today at all. I will ask Mr. Pryde to tell us what he has to say. MR. PRYDE: I have not very much to say about shooting coal with permissible powder as far as slack is concerned because we are not in the commercial business. All of our coal goes to the railroad and a very large part of it is crushed for use in the stokers of the locomotives. We are on a 100 per cent permissible powder basis and as far as I am able to see, I do not believe that the percentage of slack is increasing with its use. We find it hard to convince our commercial neighbors of this fact because they are naturally very much against increasing their percentage of slack on ac- count of the low price received for this grade of coal. I, personally, believe that where a change is made from black powder to permissible powder the percentage of slack will be increased for a time because the miners have been accustomed to using black powder and they are rather suspicious about going to the permissible powder and I do not believe that we can blame them very much. So the tendency with them is to use too much powder. We have gradually overcome this, although, as I said before, we have not kept close track of the production of slack. However, we try to get as large an amount of lump coal as possible. Broadly speaking, I can say from observation that in my opinion there is very little difference in the percentage of slack with the use of the permissible powder that we have today than there was with the use of black powder. I also get this information from our mine superintendents. Mr. Peterson and the other explosive men have been very helpful to us in the use of permissible powder and I confess I have to take everything back that I said several years ago. At that time I was against permissible powder, particularly on account of the cost, but, with the newer permissible powder, we have gotten the cost down very well. I know today that the cost of permissible powder in the coal mines of the Union Pacific Coal Company is less than when we were using black powder. I know this because of the fact that we kept a record of the number of tons we got with black powder, and the number of tons we get with permissible powder compares very favorably in cost. I know this, too, because of the fact that our employes, except in the first few weeks of using permissible powder, have made no demand upon us for any in- crease ill pay to offset any added cost that might accrue in the use of permissible powder and the fact that they have asked for no increase is very conclusive proof to me that it is not

Jan 1, 1925

By D. J. Griffiths

Beyond doubt it is practically impossible to eliminate all chances of accidents from falls. Mother Earth is not going to give up her treasures without some sacrificing on our part. This particular question ranks among the important subjects connected with coal-mining, and has been given less attention as a factor of life- and limb-destroyer than any other cause. The single fatalities which happen create very little attention; nevertheless, when counted up at the end of the year, they outnumber the unfortunate ones that are mowed down by the wholesale by mine explosions. Fire-damp and coal dust were often considered the greatest evils in coal-mining. All records, however, prove this conclusion to be wrong. The second annual report of the Bureau of Mines gives the loss of life caused by falls of coal and roof in 1910 as 1,310, and in 1911 as 1,321. The reports of Pennsylvania mine inspectors for a period of thirty-three years show that 59.38 per cent of all the accidents underground were caused by falls of roof and coal. Also, the Bureau of Mines shows in its last issue on fatalities that accidents from fall of roof and coal killed more men than any other two causes combined, and that they account for more than half of the deaths under- ground. It seems we are getting too accustomed, taking too many things for granted, running too many risks, trusting too much for the best, and preparing too little for the worst. We must remove the cause; then the effects will cease. However, I can see that a better day is here. The main damaging factors underground are falls of roof and sides. A bad roof is tender and lacks the adhesive qualities to sustain its own weight over comparatively small areas. A roof of any character which is frequently penetrated by well-defined slips and cleats, is characterized as a treacherous roof. The carelessness of men has been one of the main causes of most of the accidents in mining as well as in any other industries. Three Grades of Miners Miners can be classified into three distinct grades, to-wit: the experienced and careful, the experienced and reckless, and the inexperienced. The accidents which the first class usually meet with occur through the carelessness of their co-workers, as well as through accidents which are termed unforeseen, such as falling roof between timbers, and between the timbers and the face of the coal. This may have 'previously given evidence of being absolutely sound and safe, but be released by invisible slips or by sudden outburst of occluded gases in large quantities, as we term big blowers or feeders,

Jan 1, 1913

By Graham Bright

Up until a few years ago most of the electrical equipment used in the mines of this country was developed for industrial purposes and was adapted for use in mines by slight modifications. It became apparent, however, that mining conditions differed widely from most industrial applications and it became necessary to design and develop apparatus, particularly suited for use under mining conditions. Most of the electrical apparatus used in mines today, however, does not owe its success entirely to mining development, but in many cases developments in other branches have been taken and improved upon and modified to meet mining conditions. Power Plant: In the earlier days the power plant for the production of electric power usually consisted of fairly small belt driven direct current generators operated from reciprocating non-condensing steam engines. Today where possible the mines purchase power from central stations and where not possible it is ususally produced from turbine driven plants using non-condensing turbines for the smaller plants and condensing turbines for the larger plants. The bad water conditions at many of the coal mines in this country is, responsible in a large measure for the high cost of upkeep and repairs in isolated power plants. This feature with the type of labor available makes it difficult to operate an isolated plant condensing except in the larger mines where water conditions are good and the apparatus can be taken care of. The geared turbine is a particularly simple and rugged piece of apparatus and requires very little attention over long periods of time. Hoists: The first electric hoists to be installed used various types of motors designed for railway or industrial purposes, and the control furnished was far from satisfactory. Today most of the mine hoist motors are of the alternating current type, especially designed for hoisting service. The control for motors of 200 H. P. or over is usually of the magnetic of liquid rheostat type, and as built today will operate over fairly long periods with a very moderate cost of up-keep. Hoists of 1000 H. P. or larger are usually of the direct current type using field control and receiving power from a flywheel or synchronous M. G. set. Hoists of this type have made remarkable records in regard to continuity of operation and low cost of up-keep. Where high speed operation is desired in either coal or metal mines, the D. C. equipment using field control and a separate M. G. set to supply power to the hoist motor is not only the safest and most economical but in many cases is the only type of equipment capable of satisfactorily obtaining the output required. A number of improvements have been brought out with the field control scheme in connection with the acceleration, retardation, overfeed and overwind of the hoist. With these new developments the hoist operator can no longer abuse the hoist by improper manipulation of the control handle. Until a few years ago the matter of safety devices was not given much consideration when installing hoisting equipment. At the present time the safety devices are considered one of the most important items in connection

Jan 1, 1922

By D. A. Stout

The Rouse Mine, belonging to the Colorado Fuel & Iron Company, earlier known as the Santa Clara Mine, is located at Rouse, Huerfano County, Colorado. Operations at this property started about the year 1899, after the old Rouse mine had been drowned out by a large flow of water coming from the strata underlying the Cameron seam. The present new Rouse mine was opened by a slope on what is familiarly known as the Walsen seam in the Walsenburg district. This slope has an average grade of 12 per cent bearing approximately, south 45 degrees west, and having at the present time a total length of 6300 feet. This seam has an average thickness at that property of five and one-half feet; however, there are sections of the mine where the thickness is from seven to eight feet. The mine has been developed. since the time it was opened on what is known as the Room and Pillar system ; water level entries have been driven right and left off the slope, and in some cases the rooms are driven directly up the pitch; and in other cases entries have been driven with rooms turned on water level courses. The first flow of water of which we have ally record was encountered in 1901 in what was called the "Second West Entry." This flow, however, was small, and did not require the installation of any large pump unit. From 1901 up until 1909 the flow increased normally as the field was developed. In January, 1909, the first large inflow occurred, coming from a break in the seventh west entry, making a total flow at that time of about 500 gallons per minute. This necessitated putting in larger pumps, and the first pump to be installed of the centrifugal type was a 600 gallon Worthington. By the year 1911 the water had increased, due to additional development, until it was found necessary to install an additional 600 gallon Worthington centrifugal type pump. In December, 1912, a break occurred in the eighth west entry, between the fourth and sixth cross entries, making 2000 gallons per minute. This flow decreased after a period of three weeks some 500 gallons, but on account of the quantity of water then being handled at the mine, and in view of the fact that we needed some reserve pumping equipment to take care of these flows, and additional 600-gallon Worthington centrifugal type pump was installed in June, 1913. An the latter part of 1914 a 250 gallon Reese roturbo was installed to take care of the water, which was being made in the lower workings of the slope. We found after the installation of the centrifugal pumps that the water decreased to a certain degree in the uppermost workings. This led us to believe that the field was being drained, more or less, and the head reduced ; however, our ideas in regard to this were again upset in December, 1915, when we encountered a flow in room 6 off the first cross entry on the ninth east entry. This flow was not as large as previous flows had been, but made 200 gallons per minute.

Jan 1, 1921

By B. W. Dyer

At about 8:30 o'clock on the morning of March 8, 1924, an explosion occurred in the Castle Gate No. 2 Mine of the Utah Fuel Company, Castle Gate, Utah, and 171 men lost their lives. The explosion was caused by the ignition of a comparatively small body of gas and was propagated throughout the mine by fine coal dust which had accumulated on the roof and ribs of the mine and by coal dust made by the explosion itself. Castle Gate No. 2 Mine was one of the best kept mines in the state and it was believed not only by the officials of the Utah Fuel Company, but by all others connected with the coal industry of the state that this was one of the safest mines in the entire state. The state had not been visited by a catastrophe for over twenty years and it was a general belief that the mines were kept in such condition that a catastrophe was almost impossible. During the preceding twenty years new mining officials from other fields had entered the state and seeing that sprinkling as done in Utah was far more elaborate than in most other coal mining sections of the country, caused them to believe that they were keeping their mines in an absolutely safe condition. When coal -mines suffer no mishap during a period of twenty years the general attitude relative to safety may become somewhat lax, not only with the operating officials, but also with the State Inspection Department. However, there were some who were more keen to appreciate the hazards of Utah coal dust and who predicted that if Utah mines were kept only damp but not wet, some day the state would be shocked by the news of a dreadful disaster. In a paper prepared and read before the Salt Lake City Chapter of the American Institute of Mining and Metallurgical Engineers in 1924, Mr. D. Harrington stated: "The writer had his first mining work in Utah mines spending nearly ten years in Utah, starting just after the Scofield explosion in 1900. After having been absent from the state for about eight years upon returning and spending a few days in a few properties, there appeared then to be a definite relaxation as to precautionary methods especially against dust; some of the properties which in 1900 to 1910 would have stopped work if for any reason water was not available for sprinkling purposes, were in 1918 definitely dry in many places, and in some instances there was also definite relaxation as to shooting regulations, some properties with electric shooting systems were allowing firing of certain shots while the men were in the mine. The Utah coal. dusts are too inflammable and explosive to allow of taking any chances and unless up-to-date and carefully maintained, the Utah coal mining world will hear to its dismay, that the very excellent record of the past twenty-three years as to explosions has been shattered. Hence, possibly it was not altogether a complete surprise that such a disaster occurred in Utah, but it was a surprise to many that it occurred in one of the best kept mines in the state and it was that fact that led the coal mining men of Utah to believe that the state coal mining laws should be modified.

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 J. C. Rae

A Japanese mining engineer was given a year's leave of absence by his company and dispatched on a tour of inspection of all the principal coal mining regions of the world. He visited the New Castle region of England, Wales, Scotland, France, Germany and Alsatian mines, the underseas col¬lieries at Nova Scotia and Vancouver, and our own important fields of Illinois, Pennsylvania, West Virginia, Kentucky, Colorado, Utah and Wyoming. You are probably surprised to know that after seeing all these, he pronounced the Gebo mine of the Owl Creek Coal Company as the most interesting operation he had seen. The Gebo Mine is located about three miles west of Kirby on the Chicago, Burlington & Quincy Railroad in the Big Horn Basin region of Wyoming, 500 miles north of Denver and 200 miles south of Billings, Montana. The mine is working on a coal bed five or six to eleven or twelve feet' thick, dipping 22 to 23 degrees toward the northeast. The coal occurs in what is called the Eagle formation; and is found between two massive sandstones from 25 to 65 feet thick, which, weathering into bold', gray-colored cliffs, serves as a guide to the location of the coal bed. The deepest workings have an overburden of 800 feet. Cleavage planes of the coal extend at an angle of 45 degres to the pitch, and perpendicular to roof and floor. The coal itself is generally clean and not difficult to cut. It ignites readily from spontaneous combustion, however, which circumstance makes an ever-present fire hazard which must be carefully watched and guarded against. The coal is classed as sub-bituminous with analysis about as follows: Moisture 17% Volatile Matter 33% Fixed Carbon 46% Ash 4% Sulphur, about ½ % B. t. u. value a trifle under 11,000. It is known as Owl Creek coal, is one of the best domestic and steam fuels in the West, and is very popular in Montana, Idaho, Washington, Wyoming, South Dakota and Nebraska. While the coal slacks somewhat rapidly when exposed to the weather, it stores readily for months if placed under cover. On account of the somewhat isolated position of the mine as regards manufacturing establishments, there was a decided difficulty in disposing of slack, especially during the early years of the mine (1907 to 1914), and approximately 10 per cent of the entire product had to be wasted as slack during those years. This difficulty has been largely overcome since 1914, due partly to growth of manufacturing establishments in tributary territory, and also to enlarged transportation facilities. Also largely due to its isolated position, the mine has been compelled to use an extremely large proportion of box cars, much over 50 per cent of the product (in some years 75 per cent) being shipped in box cars, which, of course, entails extensive loading equipment and increases cost of loading. The output of the Gebo Mine for 1920 was 348,000 tons, for 1921, 273,000 tons; the rate of production during the year 1922 was over 1,700 tons daily, and 2,000 tons daily in January, 1923. The mine was developed by driving three openings straight down the pitch, the main slope being 12 to 14 feet wide and 3,000 feet long. A little distance from the surface a pair of level entries were turned right and left, known as the first East and first West. From these, rooms were driven up the pitch and chute mining attempted with only indifferent success: The failure of this rise-room method of mining was attributable to several

Jan 1, 1923

By D. C. McKeehan

The use of electric power was introduced in this field in the year 1892. The initial installation being an engine-driven generator and one nine-ton haulage locomotive using 500-volts direct current. Reference to this locomotive appears in the issue of COAL AGE for February 24, 1921. For a large coal field, the conversion to electricity has been very complete, there being no compressed air machines in service and but one steam driven hoist, that at No. 1o mine and located within fifty feet of the present power plant boiler room. Two eight-ton haulage locomotives, installed in 1896 and still in use, justifies the service and the equipment. These mines used the pioneer types of electric cutting and drilling machines, the story of which is, no doubt, familiar to you. The extensive use of electric power began in 1900, when there was installed four 400 k.w., 500-volt direct current engine-driven generators. These were cross-compound machines and operated non-condensing. By 1910 the mines had developed main haulage entries of several miles in length and a working territory of about six square miles in area. The necessity of supplying adequate power at the working face required a local power supply from motor-generator sets in various parts of the mine to supplement the power furnished by the engine-driven generators. The power to these motor-generator sets was supplied by a 300 k.w. high pressure non-condensing turbo-generator delivering 2300 volts, 60 cycle, three-phase current. This marks the beginning of the use of alternating current for mining purposes. In 1913 new mines were being developed at Reliance, seven miles distant, and the plant was enlarged to accommodate a 750 k.w. low pressure, condensing turbine, utilizing the exhaust steam from the cross-compound engines and the 300 k.w. turbine. Transformers were installed for supplying Reliance with power at 13,200 volts. In the course of time the old engines began to dismantle themselves by throwing various pieces, such as cylinder heads, about the building, damaging walls and switchboards, and created a general feeling of unrest among those who had to do with power production. The limitations of the old engines that had given admirable service for ten years were recognized. The source of exhaust steam became questionable and in 1915, a 1000 k.w. high pressure condensing turbine was installed in order that a more general use could be made of motor-generator sets for the direct current supply. The plant at that time containing a 1000 k.w., a 750 k.w., and a 300 k.w., in alternating current generators, supplemented

Jan 1, 1921

By Eugene McAuliffe

The subject of my few remarks addressed to the Rocky Mountain Coal Mining Institute, "Guessing or Knowing! Which," may perhaps suggest but little to you here today. However, I am sure you will all agree with me when I say that in the conduct of a coal mining operation there should be no choice between guessing and knowing. The value of, and the results to be obtained from this Institute, its meetings and printed transactions, as well as those of other similar educational organizations, depend very largely on the mental attitude of those who constitute, through their pronouncements, the more active portion of the membership. Perhaps the most apt criticism that is now being made of the coal industry is that, to an extent possibly exceeding any other industry of similar magnitude and importance, it depends for its conduct altogether too much on "rule of thumb" and "tradition," rather than on proven practice and actual fact. The records of our coal mining association meetings bear expression of many conflicting opinions, the majority of which are sincerely put forth by those expressing same as representing the facts; the extremes expressed, however, frequently fix the question raised as one yet located in "no man's land." There are yet too many chances taken we are still "weighing pounds on railroad track scales" and measuring yards with the proverbial "bit of string." The actual expense of conducting any one of the several operations incident to the production of coal is rarely determined, and in many instances the general cost figures, prepared some weeks after the work is complete, are of that sweeping character that very little can be abstracted therefrom. Many coal companies are now making a daily cost sheet, showing the cost of labor and material in detail, as used in the several related operations,, and such is decidedly helpful, particularly to the mine superintendent and his foreman, who, without such, sail an uncharted sea; the auditor's belated monthly summary rarely ever seen by these men who are held responsible for the labor and material used. I have made reference to this situation as an accentuation of the fact that the coal industry contains more "serious minded, conscientious guessers" than does any other similar industry, although the annual cost of our product runs up well beyond the billion dollar mark, and what is more important, our industry is one that still continues to exact a heavy toll of human life. Now this brings me to the question of safety, the one question that should be, and which is, I know, uppermost in your minds. The coal mining world, engineering and operating, is now well sold on at least two things the theory of using permissible explosives and the elimination of the open light. Furthermore, the industry, particularly that portion which is located in Great Britain and the United States and Canada, are now planning vast extensions of the use of "rock" or "shale dust," both in the form of "dust barriers" and in "direct application" to entries and cross-cuts. This is well; however,, my study of past mine explosions has convinced me that the great majority of such had their very beginning in gas accumulations; frequently originating in restricted areas at the working face, in abandoned worked-out areas, or in some other certain place where ventilation is not, maintained as it should be; and that again leads me to the point where it can again be well said, that there is too much "rule of thumb," too much guessing now being done in regard to the volume of air required, and continuously furnished, in a given entry,, panel, room or area. Just to emphasize this situation, is it not a fact that the majority of mine inspectors express the ventilation conditions as measured by them, in terms of cubic feet per man employed, in each certain split, and does not the mining laws of many states yet demand a minimum of "100 or 150 cubic feet

Jan 1, 1924

By S. W. Farnham

We have listened to many papers describing mechanical loaders, and systems of mining planned to increase their efficiency. We have become familiar with the various types and in a general way, their capacities and limitations. Messrs. F. E. Cash and E. H. Johnson in Bulletin 17 of the Carnegie Institute of Technology, subject Coal Mining Investigations, have a very complete review of the loading situation then. Mr. A. W. Dickinson, in a recent paper before this Institute, gave a later illustrated review of mechanical loaders. On page 28 of Cash & Johnson's paper is a list of loading machines to which might be added to bring the list down to date, the following: Under Digging and Loading Machines The Goodman Power Shovel Under Scraper Loaders The Goodman 436-G-3 125 H. P. three drum Scraper loader The Goodman 35 H. P. Entry loader and the Two Drum 125 H. P. Hoist built by Vulcan of Denver for scrapers Under Shaking Trough Conveyors The Eickhoff Conveyor The Link-Belt Conveyor The McCarty Duck-bill which is really a digging and loading element built to attach to the end of and operated by a reciprocating conveyor. The outstanding feature in this line of work in the past few years is the fact that a few very successful operations have been worked out on a large scale; the officers and staff in charge of this work have gone into details very thoroughly and altered and improved, in many cases, their mine equipment and mining methods, and by the exercise of persistent energy and intelligent effort, in the face of frequent difficulties and discouragements, they have attained results that are far ahead of the average loader operation. The coal mining industry owes much to these men for the pioneering and development of mechanical loading; their investigations in transport, shooting, shearing, snubbing, cleaning, and production costs, the results of which they have given freely and frequently to the public, are of great value. Foremost among the pioneers in this work are the Union Pacific Coal properties, the Quealy properties, the Sheridan Wyoming Coal Company and in the Central West, the Union Colliery Company of Illinois. On the other hand, in the great majority of installations, one loader, or possibly two or three loaders have been started in a given operation and through failure to make the proper effort to improve their transportation and work out the systems to utilize their loading machines, the loaders have not shown appreciable savings and in many cases, the installation has failed. It has been frequently stated in many meetings where loading has been discussed, that the idea of mechanical loading must first be sold not only to the operating staff but to the entire personnel of any company where installations are made. The problems involved in the successful application of this equipment are such that it requires enthusiastic and wholehearted teamwork on the part of everyone connected with the work and when difficulties arise, they must be ready to exercise initiative and try new ways oftentimes of overcoming impediments. The closest attention now is given to the question of economics how much will a loader reduce the cost of coal in any particular situation? Without fear of successful contradiction, I believe that experience up to date has unquestionably shown that where the shovel type of loader can be properly used, it produces in wide work, the cheapest coal of any loading device yet brought onto the market. Naturally there is a considerable difference between the results from different makes of shovels.

Jan 1, 1926

By Samuel Tescher

The operation of gaseous mines is a problem, due to the fact that we have not only the ordinary mine accidents to guard against, but have also the ever present menace of a mine disaster involving a large number of human lives, and the destruction of valuable property. In looking over the reports of mine disasters throughout the country in the past several years, we find that methane gas, coming in contact with an ignition agency of some kind, has been the source of at least 75 per cent of our mine explosions. Coal dust, of course, plays its part in propagating the explosive action throughout the mine workings and rendering it more violent and destructive; nevertheless, the initial ignition of a body of explosive gas-sometimes of very small volume-has been the primer for the large majority of our mine disasters. We find also, that the places of initial ignition are most frequently found at the working faces, or in close proximity thereto. This is mainly due to the following reasons: First-The working faces are, as a rule, the places where methane gas is most freely generated. Second: They are places that are most poorly ventilated. Third-They are the places where ignition agencies are most frequently found. The sources of ignition, as a rule, consist of naked lights, the shooting -of shots, defective flame safety lamps, and electrical arcs. The problem, then, in the operation of gaseous mines, is primarily to so ventilate the working faces that an explosive mixture is not likely to occur, and to endeavor to keep away from the working faces all sources of ignition. To do both of these things may seem impossible. Nevertheless, by working along both of these directions, a great many disasters can be avoided. The efficient ventilation of the working faces is paramount. By efficient ventilation, we mean the continuous passing of large volumes of air at the working faces. This can only be accomplished by adequate ventilating equipment, capable of being driven by at least two independent and distinct sources of power, together with large, clean, straight air courses which are free of short turns, constructed areas, and leaky doors and stoppings. In other words, furnish a suitable course for its travel through the mine. Many of us sharpen our pencils and rack our brains to properly estimate the proper size pump and pipe equipment that may be needed to handle a certain amount of water. We estimate the size of copper conductors to a nicety. We immediately rush to repair leaks in our water, compressed air or electric lines. But how many of us give serious thought to the travel of the air through our mines, the health and safety-giving fluid on which so much depends! In driving air courses, a certain economical cross-sectional area should be adopted and maintained as standard. When turns are necessary, they should be made with long radius curves, and the cross-sectional area should be increased on the curves. All entry stoppings should preferably be built of monolithic concrete, with suitable hitches into floor and ribs, and after the concrete has set, they should be examined and leaks due to shrinkage and settling should be eliminated. Overcasts and their approaches should have cross-sectional areas larger than the entries leading to them, to allow for the sudden change of direction, bearing in mind that air wants to travel in straight lines. In the early development of a property, ample provision should be made in the size of the main entry pillars to allow for the driving of additional

Jan 1, 1925

The eighth annual RMCMI Mine Rescue Evaluation was held during the 1999 Institute convention at the Crested Butte Marriott Resort, Colorado. [ ] Elliott Tsosie, Mary Rowell, Janna Aune, Guy Horton, Art Saenz and Bill Balaz were pleased with the 1999 Mine Rescue Program, The Mine Rescue committee is but one of 17 volunteer committees; this one co-chaired by Bill Balaz, Elliott Tsosie and Janna Aune. There were three evaluators, Art Saenz, Western Environmental; Mary Rowell, ProCare and Guy Horton, Horton Rope Rescue. Nine teams participated and brought 89 participants, 26 spouses, nine children and five teens. The teams were BHP LaPlata, BHP Navajo, BHP San Juan, all from Farmington, NM; Bridger Coal Co., Rock Springs, WY; The Coteau Properties Co., Beulah, ND; Northwestern Resources, Jewett, TX; Powder River Coal Co., Gillette, WY; Solvay Minerals, Green River, WY and Western Energy Co., Colstrip, MT. To observe were members from Centralia Mining Co., Centralia, WA. [ ] Evaluators: Mary Rowell, Guy Horton &Art Saenz The three professional evaluators provided challenging scenarios for the Mine Rescue participants on the grounds of the resort property. Some attending convention were alarmed to see stretchers with "victims" and phoned the hotel switchboard to report the catastrophe. Team members had no prior knowledge of what the scenarios might be and derails were provided only as they arrived at the scenario location, with one exception. Seven to ten or more articipants make up each team. Some teams also ring an alternate and team trainer. For identification purposes, the "victims" wore white shirts emblazoned both front and back with a red VICTIM designation. There was a staged demonstration by three response teams who had not previously worked together. This was enacted on the convention floor following a Technical Session meeting attended by about 200 members. Three response teams from BHP's Navajo and San Juan Mines together with Coteau Properties' Freedom Mine provided a demonstration of their response skills. For never having worked together before, they presented a very professional enactment. This is described at length in the Welcome Session copy. Training sessions were held Saturday and Sunday to enable the teams to prepare for the scenarios. A swap meet was Saturday evening for teams to swap hats, shirts, belt buckles, stickers etc. Each participant received a royal blue golf shirt and ivory cap with royal blue bill. Culmination of the Mine Rescue program was a Tuesday morning Awards breakfast when teams were presented with jade acrylic plaques. [ ] Teams participating in the Mine Rescue Evaluation received trophies on Tuesday morning. The captains above represent BHP-La Plata, BHP-Navajo, BHP¬San Juan, Bridger Coal Co., The Coteau Properties Co., Powder River Coal Co., Solvay Minerals, and Western Energy Co. Sponsors who contributed financially to the 1999 Mine Rescue program were Balaz & Associates, CMC, Civil Constructors, Colstrip Electric, Farmington Fire Equipment & Safety, Fisher Safety, Flanders Ellctric Motor Service, Magnum Metals, Richard Palmtag, Rocky Mountain Electric Motors, Sedona Consulting and Western Water Consultants. [ ] Evaluator Art Saenz likes to have the upper hand and will take whatever steps necessary to get it.

Jan 1, 1999

CHAIRMAN LITTLEJOHN: We have with us this afternoon, Mr. D. W. Rockey, of the Industrial Educational Organization, who would like to occupy a few minutes of our time. There is still an hour left, and there is a lot more talking to be done, and when the time is up you can go. D. W. ROC'KEY (U. S. Vocational Training Bureau, N. M.) : Mr. Chairman and Gentlemen: I am sorry to say I am not more closely connected with the coal mining game. I am interested in it because I am interested in a great deal of educational work being done in New Mexico. Two years ago, this Institute appointed an Educational Committee to investigate the opportunity for education in coal mining, and you have the report of that committee; it was issued in May 1924. Mr. Littlejohn, Mr. Moorhead of the Phelps-Dodge Corporation, Mr. Dickinson, and Mr. Miller, I think, of the C. F. C I., and Mr. Pryde, were members of that committee. They investigated the work being done in Safety, Training, First- Aid, and other topics, and made a general survey of the educational problems that might be said to be of benefit to the coal operators and to the coal miners. I believe, if I understood Mr. Moorhead correctly, while this report was accepted the committee was not discharged; but everyone seemed to be a little in doubt as to whether this activity should continue. My plea here directly is, of course, to ask that they be made a permanent committee, and asked to report to you at the next meeting in February on what has been accomplished in carrying out the program that was advised by the various companies, and what success, from a standpoint of improved work and financial return to the company, has been had. I believe that the whole trend of your discussion here has shown the need or the opportunity for improved production through education. For instance your mechanical loader the need of men who are experienced along mechanical lines, rather than the old pick and shovel methods, and the need of better understanding of your problems, just as in your safety lamp discussion that came up in the report of your Safety Committee. We have also developed a new phase, a new may of getting at some of your problems at Dawson this year, that has not been covered previously. I want to ask Mr. Holman here to tell you what is being done as a starter. Remember, we have not worked this out. He will tell yon how we are making a preliminary start in training inexperienced miners with the idea of cutting the accident record and keeping the production of inexperienced men at a higher level. If you are interested in that, I would like to suggest that this committee be requested to investigate some of these things very carefully. The State of New Mexico was willing to put five hundred or a thousand dollars into this training program as an experiment. We are willing that the Institute should have the credit for it, but we want it carefully surveyed so at your next meeting or some subsequent meeting, they can say this has been a feasible project and worthy of consideration. Mr. Holman, will yon tell us a little about this? (Applause.) MR. HOLMAN: We had an idea that by putting a green man in the mine with an experienced miner, the green man would probably learn something, and not get into trouble, etc. We decided to take a certain portion of one of our best mines, cross entry room work, and establish an underground school. We picked one of the assistant foremen who was well trained in our particular mining methods, and any green man who was employed was put into this school. He was paid a salary and he trained each and every man. Each man or two men world be working in a room and we paid them the regular contract price; they were trained how to shovel coal, pick waste and various other things. Some would stay in there a month and be transferred to other portions of the mine or other

Jan 1, 1926

it may be clearly seen that one of the most rapidly increasing items in mining operations is the cost of the timber alone, to say nothing of the cost of installation. Consequently, any practical means that may be used to lengthen the life of mine timber will greatly tend to decrease mining costs and result in important economies in operation. The four principal agents by which mine timbers are destroyed are, decay, insect attack, fire and mechanical abrasion. Decay and insect attack are credited with more than 50 per cent of the total amount of timber destroyed in the mines. Numerous methods may be used to conserve mine timbers, such as better selection, preparation, storage and segregation. It frequently happens that good timber goes into places where poor timber would do as well, and timber of inferior quality is sent into places where only the best grade should be used. However, the most effective method of conservation is by treatment with some standard preservative to prevent decay. Some of. the benefits to be noted from the use of preserved timbers are; the reduction in operating costs by decrease in timber purchases; cuts down interference with mining operations due to timber failures on main haulageways; prevents excessive falling of roof in entries by maintaining timber in sound condition; conserves timber supplies and makes possible the utilization of inferior woods; reduces the danger of mine accidents; improves mine ventilation; lessens fire hazard. Our experience thus far with preservatives, while not of a sufficient period of time to establish just what length of life we may obtain from timber so treated, results obtained during the past four years indicate that the intelligent use of preservatives will effect sufficient economies in mine timber costs to justify the expenditures made for this purpose. MR. BAKER (Concluding): Now, if there are any questions you gentlemen would like to ask about our particular operations, I will attempt to answer them. J. H. EMRICK (Sullivan Machinery Company, Denver, Colo.) ; I was wondering how much penetration you get. MR. BAKER: We get between one-sixteenth and one-eighth of an inch; it is a dipping process. With pressure treatment you get-a greater absorption; that is, better than one-sixteenth of an inch. As long as there is no mechanical abrasion, it seems to serve the purpose. MR. EMRICK: Does that apply to the condition of the timber before it is treated? If it is perfectly dry, will it absorb more treatment than if it is partly green? MR. BAKER: Certainly; one of the things we do is to have it thoroughly seasoned before it is put into the preservative. We put some green timber into the mine once, and the fungus went after it right away. MR. EMRICK: What was the difference in the depth reached by the preservative? MR. BAKER: It hardly penetrated at all when it was green. It has to be sound and well seasoned. MR. EMRICK: How long was the timber dipped or treated? MR. BAKER: According to the seasoning. If it was well seasoned, it was left in the hot bath for an hour; if not so well seasoned, it was left for about a couple of hours. C. M. BILLINGTON (General Superintendent, Rocky Mountain Fuel Company, Lafayette, Colo.): Have you found it necessary to treat timber that has been charred? MR. BAKER: No. However, I suppose it has the sane effect; in lots of places they char timber for the purpose of treatment. MR. BILLINGTON: Have you ever tried lime and salt? MR. BAKER: No, this is the only thing we have tried, the creosote and the Aczol; the Aczol is a foreign product. WM. LITTLEJOHN: Which I is preferable, the Aczol or the creosote? MR. BAKER: I couldn't say as to that. MR. LITTLEJOHN: Have you had any tests as to the value of either? MR. BAKER: We have had some of the Aczol timbers in service for a little over four years; we have had some creosote timbers in service

Jan 1, 1926

CHAIR: I see a great many safety men in the audience and I hope you will all take part in using up the time that we have left. The point brought up by all was the necessity of education. It is very hard to know just how this is going to be done. We get very little encouragement to do this. At a recent meeting at Rock Springs, 100 in attendance, and most of them mine officials. Another condition which contributes to accidents is the labor turnover in many of our States. With many companies I am told from actual statistics the labor turnover is 125 per cent. Each field has different mining conditions so that men coming from one field are not always familiar with the mine conditions in the field they come to. These are conditions which have to be overcome. WM. LITTLEJOHN: Mr. Harrington brought up the subject of sprinkling. I will try to tell what we are doing at the Utah Fuel Company camps. Our dust at Castle Gate is the most inflammable gas that has yet been tested at the Pittsburgh station of the Bureau of Mines, so it is up to us to use every precaution to keep it down. I will try to tell what we are doing regarding sprinkling from tanks. We now have in operation two tanks in our locomotive roads, one in Castle Gate, one in Sunnyside. These tanks are something like 500-gallon tanks with pump on one end of truck which gets its power from the power wire and has a half circle perforated pipe on the other end of tank. This is simply hooked on to the locomotive. When the pump is started up it throws a fine spray of water all around which wets the roof, the sides and floor. We found this very successful from an economical as well as a working standpoint. A roadway that we probably would have had to pay a man at least two shifts for, covering the full distance, with the ordinary hose and spray, we can do in half a day and do it more thoroughly. We are also figuring on at the present time using the same system on rope haulage ways, which of course will have to be run by a reel from the feed lines, handling say four hundred feet each way before reconnecting. We haven't got it finished, but are working on it at the present time. MR. COLBURN: I would like to say a few words -about this question of education. Education was mentioned by all three sections of the Safety Committee. Education regarding safety might be divided into two branches. One branch is for the official at the mine to keep him acquainted with the latest developments in safety equipment and safety methods. The other part of education is for the workmen. The United States Bureau of Mines is co-operating in both directions. Safety Clubs are organized around the Bureau of Mines First Aid Training, but it is the idea to expand those clubs and teach the miner the advantage of such-things as the closed safety lamp, and also the regulations that have been made for his safety. In Illinois we can't operate with the closed lamp, because the miners in that section of the country are not educated to the advantages of the safety lamp. Another form of education has been taken up by the National Safety Council, consisting of voluntary organizations similar to the Institute, to which all mining men are invited to attend. Such conferences nave been held in the Lake Superior district, in Butte, and in Globe, Arizona, this year. These are to be extended throughout the coal mining regions. CHAIRMAN PRYDE: The Union Pacific Coal Company has also built two tank cars of 600 gallons capacity each. The tanks are connected with hose, so that water can flow from one tank to the other. A centrifugal pump is mounted on a truck, and connected to the front tank. This pump takes its power from the trolley wire. The discharge from the pump is perforated, so that it sprays the floor and sides of the entries. We expect to use this water train on main haulage ways where we have no sprinkling line.

Jan 1, 1923

forated, allowing the completion of the removal of wash water. When discharged into the washed nut bin, the coal is moist but carries so little water as to not be objectionable to the trade, nor to give any difficulty from freezing during the coldest weather. The rock and bone from the primary jigs is elevated to a 15-ton bin by means of a single strand scraper conveyor 40 feet center to center operating on a 45 degree incline, carrying 12" x 5" scrapers every two feet. This conveyor travels at a speed of 100 feet per minute and has a capacity of 17 tons per hour. From this bin, this material falls into the third or rewash jig similar in all respects to the first two, which discharges the rock waste directly into a 15-ton refuse bin below and the bone into a short dewatering conveyor which delivers into a similar 15-ton bin from which the bone is taken to the powerhouse. The oversize and water from the shaker screen, the water from the dewatering conveyor for both the washed nut and bone, and the sludge and wash water from the three jigs, are delivered by launders to the first compartment of a three-compartment settling tank. Most of the coarser broken coal is deposited in this tank, from which is it continually removed by a bucket elevator carrying 8" x 5" perforated buckets operated on a 60 degree incline at 200 feet per minute, capable of delivering 25 tons per hour to the 50-ton washed coarse slack bin. The water passes successively through the three compartments of the settling tank and from thence through a six-inch pipe to a centrifugal pump, circulating 900 gallons per minute against a 32-foot head. A four-mesh screen 30" x 72" in the third compartment of the settling tank removes the chips of wood, paper, and the other trash, which otherwise would accumulate in the water. Water is provided from the camp water system, deriving water from the well located in an arroyo bed. During the summer months just passed, the water used, has been 108 gallons per ton of raw nut, or 146 gallons per ton of washed nut. The water meter had not been installed last winter, but it is estimated that operating at capacity, the washery will be found to require only about 75 to 100 gallons per ton of raw nut. It has not been found necessary, nor advisable, to attempt to dry the sludge from the settling tank, nor to save the water from leakage of the tanks and bins. The sludge from the jigs is washed into the settling tank and the sludge from the settling tank is washed through a tile drain to the arroyo. The jigs, shaker screen, circulating pump, washed slack elevator, and the rock handling conveyor, are all driven from line shafts driven by one 40 H. P. motor, each jig driven through a clutch. The belt conveyor and the washed nut conveyor, have separate motor drives of five and seven and a half H. P. respectively. The washer is housed in a corrugated iron building, which is partially heated by steam coils. One attendant is required for operation, regulating the feed of the jigs, the supply of water, removal of the rock, and oiling and maintaining the machinery. The rewash jig is operated only intermittently. About eleven per cent by weight of raw nut is removed as waste and four per cent goes to the washed slack bin. No control analyses of the products have been made; the efficiency of the plant being determined only by the physical appearance of the products; but the washery has been a source of pride and satisfaction to all those connected with it. As mentioned before, it has caused no interruption of operation and it has assisted materially in creating an unprecedented demand for ALAMO nut. MR. CHARLES: If there are any questions, I shall be pleased to endeavor to answer them. MR. LITTLEJOHN: Mr. Charles, do I understand it is the nut only that is washed there? MR. CHARLES: Yes, sir. MR. LITTLEJOHN: What did you say the size was? MR. CHARLES: Through three inch round perforations, retained on

Jan 1, 1926

PRESIDENT MOSES: I thank you, Mr. Emrick. Mr. Shubart would like to supplement your paper with another article. SECRETARY SHUBART: My paper really should not supplement Mr. Emrick's paper, because I secured some data from him, I knew Mr. Emrick had had a great deal of experience in shearing and I thought he could give you some useful data. (Here Mr. Shubart read the following:) "For the past two years, there has been considerable discussion among coal mining men concerning the advantages of a shearing cut in addition to the undercut, in mine work. We have had a number of requests for information on sheared coal. We were asked questions like these: What percentage increase in lump can be obtained from sheared coal? What has been the experience of mine men who have employed the shearing cut? Is the shearing cut a means of increasing the lump content? If so, is it increased to such an extent as to warrant the installation of shearing machines? Upon investigation it was found that no one could give us any definite information on the subject as no one had weighed separately the grades of coal produced from' the shearing cut. With a view of getting this information first-hand, the Goodman Manufacturing Company built up a shearing machine to be used in experimental work only. The officials of the Troy Coal Company were eager to share in the expense of obtaining this information, so that in May of this year we shipped to their mines our first type 319 shearing machine. The Troy Coal Company operates a mine at Troy, Illinois, in the No. 6 seam and produces about 275 tons daily. The coal seam averages five and one-half feet in thickness. Previous to the arrival of the shearing machine the coal was undercut six feet deep by a' Goodman Shortwall Machine. To break down the coal required two shots in the entries and three in the rooms. The percentage of lump measured over two-inch screens, averaged 58.2 per cent. The conditions of the mine were very favorable for obtaining accurate weights on the amount of lump and slack coal run over the shaker screens. The shearing machine easily cut the entire tonnage of the mine so that all coal dumped into the railroad cars had been produced from a shearing cut, in addition to an undercut. Accurate records were kept of the railroad weights and front this data the percentages of lump and slack were computed. During the month of June the percentage of lump produced over two-inch shaker screens was 69.9 per cent. This result demonstrated that the introduction of the shearing cut had increased the percentage of lump twenty per cent. The entries were driven ten feet wide and the rooms thirty feet wide The shearing cut was made near the center of the face in all places. A hole was drilled in each rib and the coal shot down with one-half the powder required when the places had been undercut only. The coal was broken down to the back of the cut so that very little pick work was necessary to load it out. The benefits derived from the shearing cut were as follows: 1. Increased percentage of lump, thus increasing the average price of coal per ton. 2. Preservation of a tender top due to the decreased amount of explosive used. 3. Facilitated handling of coal by the miner thus increasing the tonnage per man. 4. Eliminated coal yardage in entries and crosscuts of ten feet or less in width for the reason that the shearing cut provides a loose end from which to shoot the coal. This applies to the union fields only, as the non-union mines do not pay for coal yardage. Based on a price of $2.50 for lump coal and $1.25 for slack coal, the average price per ton was increased

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