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By Fredrick D. Palmer

U.S. ENERGY: PUTTING PEOPLE FIRST Assessing Goals, Needs and Resources ?Decision-makers must balance the needs of average Americans with the need for: ?A strong economy ?A clean environment ?A secure nation ?Events of recent years ?terrorist acts, multiple energy crises and a global focus on sustainable development ?magnify the need to balance these principles ?Coal ?domestic, abundant, affordable and increasingly clean ?meets these needs like no other energy source

Jan 1, 2003

The first session of the Rocky Mountain Coal Mining Institute was called to order by John T. Maulsby, Superintendent of Maintenance and Planning, Columbia-Geneva Steel Division, U. S. Steel Corporation, Dragerton, Utah, representing the past-president. W. K. Dennison, Jr., Superintendent. Koehler line. Kaiser Steel Corporation. Raton, New Mexico, who was unable to attend. Mr. Maulsby welcomed the members and guests, and introduced the President, A. Z. Dimitroff, Mining Electrical Engineer, Health and Safety, District 1-L, U. S. Bureau of Mines. Denver. Colorado. The text of President Dimitroff's address of welcome is as follows: The President's Remarks Guests and Members of the Rocky Mountain Coal Mining Institute: The distinct honor and privilege of officially welcoming you to this, the fifty-seventh regular meeting of the Institute, is indeed a pleasure. Your officers and committees have tried to provide a varied program which I am sure should have something of interest to all of us. The theme of this meeting, "Where Do We Go From here'?", appeared rather fitting for the In¬stitute this year because, as most of you know, until only two weeks ago we thought that this is the last time we will be able to meet at the Colorado Hotel, which has been the favorite spot of most members. Your officers and many of you were literally asking just that question.

Jan 1, 1961

Meeting called to order by President Herres, eleven o'clock A. M., Monday, August 27, 1928. Address of Welcome by Mr. T. S. Taliaferro, Jr. Address by Mr. William Redshaw, Chairman of the Rock Springs Chapter of the Institute. Paper, "The Effect of Mechanical Coal Mining on Mine Safety," by Lyman Fearn, State Mine Inspector, Wyoming. Paper, "Safety," F. C. Miller, Chief Chemist, Colorado Fuel & Iron Com¬pany, Trinidad, Colorado. Afternoon session, meeting called to order two P. M. On suggestion of Mr. William Littlejohn, the President appointed a special resolutions committee, consisting of Messrs. P. J. Quealy, R. L. Hair and William Littlejohn, to draft resolutions protesting against the granting of a franchise for piping natural gas into Salt Lake City, to be sent to the City Commissioners of Salt Lake City, with carbon copy to the Utilities Commission of Utah. The Committee submitted resolutions which, upon motion of Mr. Littlejohn, and seconded by Mr. Butler, were adopted and sent by telegraph to the Utilities Commission and the City Commissioners.

Jan 1, 1928

By Lloyd Garrison

The Garrison Automatic Domestic Stoker is a device intended primarily for residences and small apartments. In the development of the device com- [ ] mercial features have been given as much consideration as have engineering features. As a result of this consideration the stoker is well within the reach of the middle class buyer as regards price, while at the same time it possesses all of the features of comfort, economy and convenience which accompanies this type of stoker. The stoker is of the over feed type and uses the natural draft of the furnace. A 1/12 H.P., 1,800 R.P.M., motor drives a small worm gear unit through [ ] grooved pulley and rubber belt, effecting a speed reduction from 1,800 to 6 R.P.M. The gear shaft drives a slide situated in the bottom of the coal hopper that causes the coal to be deposited on a link belt chain which carries it through a trough and drops it on the grate. Use of a screw feed has been purposely avoided because of

Jan 1, 1925

By Richard L. Lawson

The coal producers of the Rocky Mountain states have led in one of America's true industry revolutions - the leaps in productivity and competitiveness that deliver coal-fired electric power to the U.S. economy at prices that are the competitive envy of the world. You are a primary reason the average price of industrial power in the U.S. - the power that creates and upholds jobs - is: ? 10 percent below the French average, where nuclear power is dominant; ? 37 percent below the average for industrialized Europe; ? 49 percent below the German average, where subsidized coal and nuclear rule; ? And 73 percent below the Japanese average where nuclear and liquified natural gas dominate. There are interests ambitious to change all of that; and they will be a subject of my remarks, some by name, rank, and affiliation. Coal-fired power plants in the Rocky Mountain states deliver some of America's lowest cost electricity; and America's coal-fired plants deliver some of the world's lowest cost electricity. Represented here in one room are producers from states that deliver more than 40 percent of America's coal and five of her top 10 producing states. You are cornerstones of America's economic strength and future growth. The theme for this meeting is "The Many Partnerships of Coal;" and, in this keynote, I'd like to offer a variation on the theme. I'd like to discuss a determined partnership that is dedicated to overturning everything you have accomplished, plus the structure of our society - very dedicated, very patient, very determined. This partnership masks itself as being in the public interest but behind the mask a political alliance of three distinct private interests can be seen: ? One is ambitious for economic reward as a right and without the trouble of effort; ? One is ambitious for economic advantage in trade without the trouble of competing; ? And one is ambitious for the power to govern people without the trouble of winning consent in elections - to change the way other people choose to live in accord with their own passionately held beliefs. The international agreement on climate is being used as an artifice to advance these interests, and the interests are making the United Nations a mechanism for achieving those objectives - for turning the screw, so to speak. The President that Americans elect this year soon will come under intense pressure from these partners to: ? First, quickly adopt policies that will raise U.S. energy prices and restrict use under the climate agreement; ? And in 1998 - if they follow their own published plans - to begin the subordination of the independence of the United States to a collective sovereignty in economic, political, legal and other matters. The Worldwatch Institute inaugurated this pressure last year with a policy monograph entitled Partnership for the Planet: An Environmental Agenda for the United Nations. This is but one indicator of the situation I ask you to consider. The pressure will increase after the election. Worldwatch is one of those intellect-oriented "public interest" groups whose work often leads to policy proposals and debate. Worldwatch gets money from the U.N. Population Fund and the MacArthur Foundation among others. And so my remarks require wading waist deep into one of the more sporting current propositions of American public policy - discussion of ambitions for and within the United Nations to achieve that which the ambitious call global governance. Since last year's media focus on the militia movement - and talk of black helicopters - any

Jan 1, 1996

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

FEBRUARY 26TH. MORNING SESSION: The sixteenth regular meeting of the Rocky Mountain Coal Mining Institute was called to order in one of the private dining rooms of the Albany Hotel, Monday morning, at 11 o'clock, with the President, F. W. Whiteside, in the chair, one hundred and one members being registered. The minutes of the previous meeting were read and approved. The Treasurer reported the finances of the Institute in excellent shape. The President appointed J. B. Marks, J. S. Veach and W. A. Ream as a Resolution Committee, and Frank A. Young, M. B. Urquhart and G. A. Murphy a Nominating Committee. There being no further business the meeting adjourned. AFTERNOON SESSION: The afternoon session was called to order in the Ball Room of the Albany Hotel, with approximately one hundred members present, President Whiteside presiding. A. L. Jones read his paper entitled, "The Power Problem of the Coal Mine," and C. E. Drennan, his paper, "Why Alternating Current." These papers were thoroughly discussed, after which the meeting adjourned. EVENING SESSION: At 6:45 p. m. two hundred and fifty-three members and invited guests met in the Ball Room of the Albany Hotel for the banquet. Harry F. Nash was toastmaster, and George Sanford Holmes the principal speaker. Following Mr. Holmes speech, H. N. Wheeler delivered his humorous oration of the "Annexation of Cuba;" following this certain members of the Institute gave an entertainment depicting a fictitious meeting of the United States Coal Commission. Chester Mott, formerly a member of the Institute wrote the words and songs of the entertainment, and directed it. After the show the assembly enjoyed a dance.

Jan 1, 1923

By Paul Schmechel

This time of year, our lawn is host to goodly numbers of birds - robins, English sparrows, finches of various flavors and some whose names I don't know. We lure them with a feeder in our backyard and I'm sure Patti and I spend several minutes a day watching them through a picture window that overlooks their coming and going. And, while the picture window supplies us with a constantly changing view, it does not treat our winged friends nearly so kindly. You see, at certain times of the day, reflections on our window feed back to our birds a mirror image of the backyard. Lifting off from the bird feeder, they see before them what is behind them. And, not infrequently they fly straight into the window. They stop abruptly, of course. It has to be quite a shock to discover that what is behind you is not the same as what is in front. At this point, I might be tempted to say something about bird brains - except for the fact that we humans also are prone to deceptive images thrown up by the past. Today, I think we hear a great many voices painting past images as they look to the future. We hear that the price of oil soon will rise to its former elevated position; the price of copper will bounce back; a hungry world soon will escalate the demand for food and our agricultural industry will be back in the black. In fact, we can hear hope from many voices telling us that our major resource-rich, basic industries are poised to fly up. I can hope that the voices are right, but I keep thinking that those expressions come from people seeing false images. Most certainly, it is more comfortable to see the past, rather than acknowledge that the world economy is being restructured and that the restructuring is affecting the Rocky Mountain states profoundly and negatively. The worst mistake we could make may be to place too much credence in the images from our past. We can be lulled into a dangerous complacency. What we need is a tighter belt and the will to do some serious bootstrapping. Before proceeding, I would make two points: First, it is not my intent to be a prophet of doom. But I do think we need some healthy doses of realism, if we are to avoid the shock of flying into a false future. Second, by now you have detected that I have choosen to diversify the assignment you handed me on utility diversification. As I proceed, you soon will see that the roots of diversification for many utilities lie in the subject that we ponder now. We could begin in many places, but let's start with energy. It is pervasive in our businesses and industries. We all use it. And, despite conventional economic wisdom, we are using less of it. The price is down, but we have not reverted to our profligate ways. That is true whether you look at the industrial customer or the residential consumer. As a nation and as a people, we have learned to do more work with less energy. A few statistics illustrated the point. If we use 1973 as the base year, energy use in the United States has declined almost I percent. If we examine the year of peak energy use, 1979, the decline approaches 7 percent. Let's look at it another way. In 1973, for every dollar of gross national product, the United States consumed 27,100 Btu of energy. Last year, 1985, the comparable figure was 20,700 Btu - a decline of 24 percent. So, not only are we using less energy, but we are using it more efficiently. Even though the price of energy has declined, we are unlikely to use substand with natural gas and petroleum consumption. Use of natural gas has dropped almost 21 percent since 1973. Petroleum consumption has declined 1 I percent since 1973 and almost 19 percent since 1978, when the U.S. used a record quantity of petroleum. We also know there's been no appreciable change in amounts of oil and gas used since 1981. We weathered both a sharp recession and a healthy recovery without altering the amount of those fuels used. That the use of oil and gas dropped sharply, while the total use of energy merely slumped a bit is easy to explain. The use of coal, nuclear power and hydroelectricity from 1973 through 1985 increased almost 48 percent. Some people will tell you that the large decrease in the price of oil and gas will result in increased demand that will displace coal, nuclear and hydropower. In turn, demand will force the price of oil and gas upward. I doubt it. From the poking around I've done on the subject, I suspect there may be some short-term displacements, but they will be, for the most part, cancelled out by declining use among existing customers. For instance, we all know what has happened in the automotive sector. In 1973, the average U.S. automobile made 13.1 miles to the U.S. gallon of gasoline. In 1984, the most recent available statistic, the average auto made 16.94 miles to the gallon. That's a 19 percent improvement. Because annual miles driven per automobile are essentially unchanged over the period and the number of cars on the road is not increasing, we are witnessing a drop in this segment of the petroleum market. That trend will continue. Now, let's look at energy consumption patterns still another way. Between 1973 and 1985, consumption in the residential and commercial sectors of our economy increased total energy use by 11.2

Jan 1, 1986

By Bob Burnham

Agenda 1 Overview of forecasting process 2 Review of Pre and Post Recession Forecasts 3 US Demand/Supply Summary 4 Coal Demand by Region 5 Coal Distribution by Census Region 6 Coal Price Outlook 7 Carbon Cases 8 Takeaways

Jan 1, 2009

[Following is the Financial Report of the Treasurer from May 22, 1981 to May 21, 1982: RECEIPTS Cash on hand May 22, 1981 $21,815.81 Dues $ 6,800.00 Registrations 19,250.00 Banquet, luncheons, Buffet and Steak Fry Tickets $44,335.00 Less adjustment 831.68 43,503.32 Bank Interest and Certificate Interest 7,747.49 77,300.81 $99,116.62 DISBURSEMENTS Convention Expense - 1981 48,600.37 Convention Expense - 1982 2,146.65 Stamps & Stamped Envelopes 1,251.48 Stationery & Office Expense 1,259.22 Salary of Secretary-Treasurer 5,040.18 Social Security & Employment Tax 772.20 Proceedings $ 9,703.42 Less Advertising 2,290.00 7,413.42 Certificate Purchase 10,000.00 76,483.52 Cash on hand May 21, 1982 22,633.10 United Bank of Denver Savings Account 15,000.00 Money Market Certificates 40,000.00 Total Assets $77,633.10 AUGUSTA WHITESIDE Secretary-Treasurer Approved by Auditing Committee: Paul Hronich, Chairman Robert Anderson Allen E. Duncan Donald P. Huckeby Richard C. Mullins June 29, 1982]

Jan 1, 1982

[ADDISON, HERBERT Big Horn Collieries Co., Colo. Bldg., Denver, Colo. ALEXANDER, JOHN 825 So. Gaylord St., Denver, Colo. ALLAN, DAVID Lafayette, Colo. ALLEN, JOHN Ludlow, Colo. ALLEY, GERALD Box 1920, Denver, Colo. ALLISON, ARCHIE Box 562, Walsenburg, Colo. ALLISON, D. S 1331 Roberta St., Salt Lake City, Utah AMBLER, J. B c-o Ambler & Riter, Kearns Bldg., Salt Lake City, Utah ANDERSON, A. E 403 Ideal Bldg., Denver, Colo. ANDERSON, FRANK Crosby, Wyo. ANDREWS, SAM Box 91, Walsenburg, Colo. ANGUS, WILLIAM -o B. W. Snodgrass, 1575 Lafayette St., Denver, Colo. APPERSON, A. B Tramway Bldg., Denver, Colo. ARMSTRONG, C. D 420 U. S. Natl. Bank Bldg., Denver, Colo.]

Jan 1, 1926

PRESIDENT PRYDE: Any discussion on Mr. Poster's paper? MR. J. BEVAN: I would like to ask the gentleman how fine the dust has to be to cause an explosion? MR. T. FOSTER: According to the Bureau of Mines, it is claimed coal passing through a 100 mesh screen would be considered fine enough. That is all I can learn from the different bulletins. MR. BEVAN: Will the coal dust be that fine; going back in the empty cars on the tipple in the mine? MR. FOSTER: Possibly a great deal of it would be. MR. BEVAN: Will the coal dust be that fine, going back, in the empty the coal dust going back in the cars on the tipple, and into the mine? MR. FOSTER: In some places, they are wetting the cars at the tipple, -in the Rock Springs District, we have as the trip goes out, they have a big pipe, and they souse the car, and wet the load, and in some places, near the timbers; that helps to a certain extent. That does not absolutely eliminate it all, but it helps considerable. MR. WM. LITTLEJOHN (Utah Fuel Company) : I think we have all listened very attentively to the paper that Mr. Foster has just read. He has brought up a subject rather close to my heart, for a long time. He mentions particularly, the Scofield disaster, which happened the first of May, 1900; two hundred men lost their lives in the explosion; and I think it is generally conceded that is about the first time it had ever been brought to the attention of coal miners or operators that such a thing was possible, namely, a purely coal dust explosion. The term "Scofield disaster" is rather a mistake, in a way; while the mine that exploded at the time is in the Scofield District all right, it is now known, and probably was known at that time, as the Winter Quarters Mine, one of the mines which belongs to the Utah Fuel Company at the present time, and did at that time. This mine

Jan 1, 1924

The 68th Regular Meeting of the Rocky Mountain Coal Mining Institute convened in Manor Vail Lodge, Vail, Colorado, and was in session at 10:00 a.m. The meeting was called to order by Past President Max A. Robb, Vice President and General Manager, U.S. Fuel Company, Hiawatha, Utah. Mr. Robb welcomed the members and guests and was pleased with the large attendance. He then introduced President Joseph E. Ward, former District Man- ager, Denver Office, Coal Division, Joy Manufacturing Co. (Retired). A brief biography follows: Mr. Ward is a transplanted Westerner, having spent the greater part of his life in the Eastern and Southern areas of this country. In 1927, he graduated from what was then the Carnegie Institute of Technology in Pittsburgh, Pa., with a B.S. degree in Mining Engineering. He dropped out of school for a period between his Junior and Senior years and worked in the coal mines in order to obtain sufficient money to complete his education. Practically all his adult life since graduation, has been spent in or around the coal mines in this country. After graduation, he worked the next 15 years of his life as an underground supervisor, first for the Hudson Coal Co., in Scranton, Pa. and later for the U.S. Steel Corporation in Birmingham, Alabama. He then went into sales, selling basically to the coal mine industry and other mining operations. The last 13 years of his business career were spent as a district manager for Joy Manufacturing CO., 10 years of which were in the Coal Division of their Denver office, covering the Rocky Mountain area. He retired in August 1970 but still retains an active interest in the Rocky Mountain Coal Mining Institute and the Rocky Mountain Coal Industry it supports. He is a widower, his wife, Thelma having died in July 1970. He has two children and six grandchildren.

Jan 1, 1972

[Adams, Dell H Consolidation Coal Co., 3300 One Oliver Plaza, Pittsburgh, Pa. Adams, Douglas K General Electric Co., P.O. Box 2331, Denver 1, Colo. Adams, Kenneth L Peabody Coal Co., 33 Carnation Dr., Belleville, Ill. Ahlborg, William Joy Mfg. Co., 580 Denver Club, Bldg., Denver, Colorado Albrechtsen, Ray H Mt. States Resources Corp., 2330 S. Main, Salt Lake City, Utah Allen, Dr. Harry C U. S. Bureau of Mines, Washington, D. C. 20242 Amerman, Richard W Utah Cons. & Mining Co., Box 155, Fruitland, New Mexico Anderson, G. A Walker Bank & Trust Co., 848 N 3rd E, Price, Utah Anderson, John S. Utah Cons. & Mining Co., 550 California St., San Francisco, Calif. Anderson, Robert Mine Safety Appliances Co., 1881 West N. Temple, Salt Lake City, Utah]

Jan 1, 1971

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

Public perceptions about coal remain neutral to negative But gains are slowly being made as the public becomes more aware of coal as ?abundant, affordable, and increasingly clean?

Jan 1, 2006

By Harold J. Rose

It is a real pleasure to attend another meeting of the Institute. This is partly because I am a Westerner by birth and training. As a young man I had personal experience with firing Colorado and Wyoming coals. The coal industry of the United States has done an outstanding job of producing coal. We can all be proud of the industry's record of continuously adopting technical improvements in coal mining. NEED FOR MORE EFFECTIVE COAL MARKETING However, it cannot be said that the industry has done an equally good job of marketing coal. There has been a rapid growth in U. S. population, and an even greater expansion of industrial demands for heat and power. Yet coal consumption for the past several years has been no greater than it was 40 years ago, in 1912 and 1913.

Jan 1, 1954

[Adams, Douglas K General Electric Co., P.O. Box 2331, Denver 1, Colo. Adams, Kenneth L Peabody Coal Co., 301N, Memorial Dr., St. Louis, Mo. 63102 Allen, Earl W Mine Safety Appliances Co., 257 Rio Grand St., Salt Lake City, Utah Allen, Dr. Harry C U. S. Bureau of Mines, Washington, D. C. 20906 Alston, George L Mine Safety Appliances Co., 201 N. Braddock, Pittsburgh 8, Pa. Archer, Bryan J., Jr Peabody Coal Co., 421 Glenwood St., Grand Junction, Colo. Arentzen, E. M Lee-Norse Co., P.O. Box 582, Charleroi, Pa. Arentzen, L. E Lee-Norse Co., 6030 W. 55th Pl., Arvada, Colo. Arentzen, Rolf F Lee-Norse Co., Box 582, Charleroi, Pa. Artis, Cliff E Big Horn Coal Co., 247 Sherman Ave., Sheridan, Wyo. Atchison, Lee Atchison Construction Co., Drawer D, Aztec, N. Mex.]

Jan 1, 1967

[Adams, Leonard E.819 Newhouse Bldg., Salt Lake City, Utah Adams, V. H422 East San Miguel. Colorado Springs, Colo. Allen, Earl W.2636 So. Gilpin St., Denver 10, Colo. Allen, Thomas State Coal Mine Inspector, State Office Bldg., Denver, Colo. Ambler, J. B P. O. Box 591, Denver, Colo. Apperson, A. B 394 Elm St., Denver 7, Colo. Arnold, G. O Phelps-Dodge Co., Dawson, New Mexico Audin, Abel Somerset, Colorado Audis, Clement, Jr. Paonia, Colorado]

Jan 1, 1948

A great many questions were asked Mr. Bright, and Mr. Bright's opinion was given on a number of subjects. He spoke at length on spring suspension of locomotives, bringing out the necessity for better spring suspension due to heavier weights and higher speeds now developed. The subject of dynamic braking was brought up, and the opinion of the engineers present was that dynamic braking was not a desirable feature except where heavy, long, adverse grade is encountered. Mr. Goddard and Mr. Bright had a spirited discussion regarding ball bearings, bringing out the opinion of the meeting that ball bearings in motors are preferable to sleeve bearings, and the few failures so far encountered are due to improper application or insufficient size of bearing. Mr. Shubart brought up the question of locomotive speed, mentioning some high speed work on main haulage, also an interesting experiment in a large Eastern mine where very slow speed, 3 1/2 miles per hour, gathering locomotives were substituted for the high speed gathering locomotives with an increase in cars gathered and a material decrease in derailment and accident. Mr. Bright mentioned the improvement in gathering reels, and Mr. Shubart mentioned the safety in the use of the concentric cable in direct current, using the outer wire as the ground wire, so that in case of accident to the cable, the ground wire acted as a protector to the live wire, materially decreasing the danger of sparking. Mr. H. I. Smith of the Bureau of Mines brought up the question of explosion proof construction, and Mr.. Bright and. Mr. Shubart explained the construction adopted by two of the larger manufacturers. Experiment has shown that the force of explosion in motors due to gas does not exceed 150 pounds per square inch. All forms of screen or baffles have proven an actual source of danger, due to the collection of dust, usually soaked in oil, forming an active means of propagating flame, together with the fact that all these appendages are frequently left off when the motors are repaired. Modern construction eliminates all openings, screens, devices for stopping or extinguishing flame. The motor is made entirely enclosed, practically air tight, all joints are ground and all openings necessary for access and attention are closed by bolted plates. The case is made stout enough to withstand any interior explosions, and ample ribbing is provided for heat dissipation. Mr. Bright was asked regarding the use of contactor control. He replied that his company is now recommending contactor controls for series and parallel starting on all locomotives of 13 tons and over, and particularly on the tandem units that are now becoming popular in coal mining work. The question of dynamic braking and reversing was brought up and Mr. Bright explained that this made a very complicated contactor installation but they had

Jan 1, 1922