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By Arline Seeger

Overview ? Lime Basics ? NLA & Its Advocacy ? State of U.S. Lime Industry ? Present & Future ? Lime?s Use in Coal?Conversion Plant

Jan 1, 2006

By C. A. Allen

When the writers were asked to prepare a paper on this subject for this meeting of the Institute there was some question in our minds as to what to say that would be of interest to the members. You all know that Utah has some wonderful seams of good coal, on which have been opened some of the most modern mines in the United States, and that her coal operators have been putting forth many efforts to reduce losses due to accidents as well as disease. While I believe that the physical condition of Utah's mines is as good as in any other state we are not unaware of the fact that a great deal can still be done and we are always willing to frankly discuss the accident situation in the state. Dr. Murray has assembled some interesting figures showing the monetary loss due to accidents and disease which I will will proceed to give you to show the necessity of continued efforts in welfare work regardless of humane considerations.

Jan 1, 1922

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

Jan 1, 1954

By I. M. Charles

Mr. Chairman and Gentlemen: At the request of our Secretary, Mr. Shubart, I am pleased to present the following brief discussion of the Alamo Washery. In order to insure an excellent and uniform preparation of nut coal, the Alamo Coal Company erected last year a modern washery at a cost of about $50,000, in which, since the completion last December, all of the nut coal shipped from the Alamo Mine, has been washed. In part of the workings of the Alamo Mine, the coal is overlaid by a lenticular strata of slate, which invariably falls when the coal is shot down and breaks for the most part into fragments of such size as pass through three-inch round perforations, and are retained on plates having one and a fourth inch round holes with the nut coal. This "draw slate" comprises the principal impurity in the Alamo coal, and to remove it, some bone and a few small fragments of sandstone from the roof and floor, the washery was designed and erected. The few impurities contained in the lamp are readily re-

Jan 1, 1926

The 77th Regular Meeting of The Rocky Mountain Coal Mining Institute convened at the Marriott's Mark Conference Center, Lionshead Village, Vail, Colorado, and was in session at 10:00 a.m. Past President, Loren V. Linville, District Sales Manager. Industrial Products Division. Uniroyal. Inc., Denver. Colorado, called the meeting to order. He introduced President, Edward F. Ziolkowski, Senior Vice President and General Manager, Energy Development Company, Hanna. Wyoming. A biographical sketch follows: Ed Ziolkowski is a 1953 graduate from the Colorado School of Mines with a degree in Engineer of Mines. His mining career began with Pickands Mathers Company in Gogibic Iron Range in Northern Wisconsin and Michigan. In 1961 he joined Texas Gulf Sulphur Company as Shaft Mining Engineer for their Cane Creek Potash Project near Moab, Utah. After serving as General Mine Foreman. Mine Superintendent and General Superintendent at Cane Creek, he was transferred in 1969 to Green River. Wyoming as Project Manager of Texas Gulf Black's Fork Trona Development. In 1971 he joined Allied Chemical Green River Works, as Resident Manager. In 1972 he joined Energy Development Company, an Iowa Public Service Company Subsidiary, as General Manager of their Coal Development. He currently is Senior Vice President and General Manager of Energy Development Company, and serves on their Board of Directors as well as the Boards of several other subsidiaries. This past April he was elected to Iowa Public Service Company's Board of Directors. Ed, his lovely wife Pat and children live in Hanna, Wyoming. He has been a member of the RMCMI since 1973. Is a staunch supporter of his community and the mining industry.

Jan 1, 1981

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

Jan 1, 1926

T. T. READ, BUREAU OF MINES: Mr. McAuliffe has asked a very practical question. Expressed in another way, the question is: If we have decided to use rock dust to prevent coal dust from exploding, have we got to take rock, that is, solid material,, break it up and finally grind it into dust (and fine grinding is very expensive), or can we take material that is already in a pretty fine state of subdivision and thereby save the expense of pulverizing it? Most of the preceding discussion has been from the view-point of practical experience, and I should like to suggest that we have not had enough practical experience in rock dusting to be able to answer this question, from the viewpoint of experience, with the degree of definiteness that Mr. McAuliffe desires. With your permission I will discuss the matter briefly from the theoretical standpoint, because after all the theoretical considerations, insofar as we understand them correctly, will apply to every' case, whereas in coming to a decision on this matter it will be necessary to take into consideration local conditions, which will necessarily vary in every case. Considering the matter in a rather elementary way, the first point is: What makes coal dust explode? The air of this room is full of dust at the present moment, even though we do not notice it. If you were to close up the room for a week, enough dust would settle on the floor so you could write your name on it. Of course, the dust which is in the air of this room is not coal dust but even if it were coal dust and you were to bring an open light in' here we all know that the dust would not explode. The reason for that is that the dust particles are not close enough together for the flame to propagate itself from one to the next. You will probably be able to see in the demonstration in the gallery on Saturday that the coal dust explosion is practically a very rapid burning of the dust. When you light one piece of dust it burns and gives out heat and if there is another piece of dust close enough to it so that the heat from the first piece is able to bring a second piece up to the burning temperature, then the flame will propagate itself through the mixture. But, if the particles are so far apart in the air that the' heat from one particle is dissipated before it reaches an adjoining one, and is therefore not able to bring the second particle up to the burning temperature, then the flame will not propagate. To get a coal dust explosion, it is not sufficient to have coal dust suspended in the air. The coal dust particles must be close enough together in the air so that the heat from one burning particle is able to heat the adjoining particles up to the point at which they will burn. There has been some discussion of the size of dust particles that will cause an explosion to propagate, and it has been pointed out that the minus 200-mesh dust is the most dangerous, and that particles coarser than 20-mesh will not propagate an explosion. There are two reasons for that. A large particle has very much smaller surface in proportion to its weight than a small particle has. You know the old story about the Indian who when asked how he could go around in cold weather without any clothes on said that an Indian was all face. A 200-mesh particle is almost all surface and there= fore is able to burn almost instantaneously, which means that it gives out its heat almost instantaneously, whereas a large particle with less surface in proportion to its weight burns more slowly, gives out its heat more slowly, and the heat has more time to be dissipated. The second reason why coarse dust does not easily propagate a flame is because it is so hard to make it

Jan 1, 1924

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

Jan 1, 1962

By Franklin P. Wood

Unnumbered ages have passed since the time when nature's laboratories were working without the aid of capital or labor unions assisted only by earth's cooling crust and old Sol's rays, to lay the prodigious coal beds of the earth and distil the oils which now furnish the basis for the world's great industries. Strangely enough rays from the same old sun probably somewhat diminished in intensity are still drawing from earth to clouds the water that will run down hill and through man-made devices produce energy to compete with that made with the products created in ages past. So now we find that within the past century vast human industries have grown up around the products of these agencies and here we are today discussing the many problems connected therewith and among the others the subject of this paper, which is essentially the relation of COAL to OIL in industry. The problems involved are those of human relationship and are not fundamentally unsolvable when engineering skill and knowledge is properly applied. The last few years has developed a brand of pessimism that is especially prevalent in the coal industry, at any rate in the west where we come in contact with it. In any general discussion with coal men, a very short time only is required to bring out the feeling or expression that the coal business is on the rocks and the reasons run the gamut of human deviltry. We have heard that in the not far distant past corn was so cheap that the farmers were compelled to burn it and thus deprive the coal mines of their well earned right to sell coal for this purpose. We have heard that the flood of oil is so vast that it was being burned in preference to coal, and to heap insult on injury that the rail- road locomotives were burning oil in order to pull coal away from the mines. We have heard that the union was responsible for all the woes to which the industry is subjected. We have heard that the family tin lizzie is so depleting the family exchequer that coal could not be purchased and if purchased could not be collected for. We have heard that producing mines are so numerous that the profits are a negligible quantity. These are but a few of the reasons assigned for making the coal producers a class of pessimists which is not good for the industry. All these reasons given and all the others must be taken collectively and these are not the cause but the effect of a rapidly changing civilization. An analogy may be found in the experience of many of us in the electric industry a few years ago. You may remember that less than 20 years ago the high efficiency Tungsten electric globe was introduced. It was so much more efficient than the old carbon lamp that only one-third of the current previously required was needed to produce the same illumination. Consternation seized the ranks of electrical men who had little or no vision, for the out- look was that so little current would be sold that everyone would be bankrupt. This limited vision, however, did not prevail, for all engaged in the industry spurred on by necessity, accomplished many of the things that we are now enjoying the fruits of be- cause the electric industry has grown and is growing by leaps and bounds and every highly efficient improvement is greeted with rejoicing. It is well known that when the old type of carbon arc lamp began to be replaced by modern units the manufacturer of carbon rods thought his doom was sealed and yet these same manufacturers have so adjusted them- selves to conditions that the dry battery business of today is of vastly greater volume and profit than was the carbon rod business of the past. Of course, there are industries that should not have survived anyway that have gone down and out to makeway for vastly improved conditions and can

Jan 1, 1925

D. HARRINGTON: Owing to lack of funds, the United States Bureau of Mines have made no experiments in the Bruceton mines in the use of mudite. MR. McAULIFFE: I doubt that mudite cam be delivered at fifty cents a ton and that a mile of heading can be treated with mudite for ten dollars. You could not dig a ton of sand out of a sand hank for that money. L. C. CLARE: The tram road leading to Wattis mine crosses a shale bed and it is easy to screen the shale through a %-inch sieve and load it into a mine car. W. J. REID: A slow trip passing through a mudited entry will dislodge practically no dust, a rapid trip will make air disturbance enough to coat the cars with fine dust. MR. PRYDE: We have used mudite on stoppings around a fire in Reliance and for two months thought they were getting good results, but the fire was found to be drawing air and to be spreading. This mudite was smeared over the stoppings with a trowel. After this apparently failed we used dry adobe.

Jan 1, 1925

[ ] RMCMI PRESIDENT 1985 - 1986 ARTHUR K. NEILL on behalf of The RMCMI Board of Directors and Officers invites you and your family to attend The 82nd Regular Meeting and Convention of The Rocky Mountain Coal Mining Institute to be held JUNE 29, 30 AND JULY 1, 1986 Kalispell, Montana

Jan 1, 1985

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

Jan 1, 2006

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

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

Jan 1, 1975

By Donald P. Brown

[Mr. Brown did not make his speech available for reprint.] Productivity is the Answer - Always Was; Always Will Be When Bill Balaz invited me to speak here this morning, he asked me to examine the three most important issues Consol will face over the coming decade. There are more than three. But the more I thought about that question, the more I realized all our issues come down to only one. As I reviewed the U.S. coal industry over the past ten years, and as I thought ahead into the year2000, one thing stood out. Not markets. Not government regulations. Not record tonnages. But productivity. The recent history of American coal is a tale of productivity improvement. It is a story that needs telling. And understanding. Not just for the good of the coal industry, but for the benefit of the American economy. Americans today do not appreciate the value of productivity growth. I don't say that lightly. As I review recent debate over American industrial competitiveness, as I look at certain legislative proposals, I see disturbing trends. It's not that anyone is against productivity per se. But many people seem to fear the very processes that enhance productivity. Twentieth century America enjoyed unprecedented growth in productivity. And in personal standards- of-living. Those two go together. This century has been one of change. Demographics. Education. And technology. Many new industries-cable television, computer services, telecommunications, for example-have grown from mere dreams to billion- dollar enterprises employing tens-of-thousands. And some older industries have declined. The nature of work has changed-from manual work to know- ledge work. From agriculture, to manufacturing, to services. In the mid-1960s. AT&T employed more than one million people. These were not high-paying jobs: telephone operators, linemen and equipment assemblers. Today, the successor Bell companies and their new competitors employ no more than a few hundred thousand. Because of automation. Because of enormous gains in employee productivity.

Jan 1, 1988

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

Jan 1, 1926

Jan 1, 1985

Jan 1, 1992