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By L. S. Panyity

The question of natural-gas supply is receiving careful consideration in many parts of the country, as in the winter months it is quite a problem to have on hand sufficient gas to satisfy the demand. Increasing the output of wells by the application of vacuum has been tried with various results and large companies have attempted to keep up the supply with gas compressors. The possibility of storing natural gas in the sands of exhausted gas pools has been 'tried in a few instances with satisfactory results. This method may prove of practical value in solving the problem, especially in the case of towns that formerly obtained gas from their immediate vicinity but now must search for new pools. In all cases, only part of the available supply is utilized during the warm weather, so that many wells are shut-in, yet during the winter months, the supply is not sufficient even with all the wells on the line; in such cases it would be of great value if a large volume of stored gas were on hand, obtained through wells that would have been standing idle during the summer. Idle producing wells having considerable "rock pressure" will force gas into the exhausted, or storage wells, and this gas will be used only when the regular supply falls short (Fig. I). If two gas wells of different

Jan 1, 1920

By Ernest F. Burchard

MOST of the iron ore smelted in Alabama blast furnaces is mined within Alabama, although deposits in the neighboring States of Georgia and Tennessee may be drawn upon when occasion requires. Of the four commercial kinds of iron ore, the anhydrous ferric oxide, hematite (Fe2O3) ; the hydrous ferric oxide, mostly the type commonly known as limonite (2 Fe2O33H2O) ; the carbonate, siderite (FeCO3) ; and the magnetic oxide, magnetite (Fe:3O4) ; the first two are found in abundance in Alabama, the third in less than commercial quantities, and the fourth only rarely. Both the hematite and the hydroxide are found in somewhat different forms according to their geologic environment. The Red Mountain hematite, of Silurian age, that crops out in well¬defined beds for 1.50 miles northeast-southwest and 40 miles northwest-southeast is the predominant source of ore. Only a small part of this area carries ore of commercial value; Birmingham and Gadsden are now the only centers of production. The ore is of sedimentary origin, probably altered from vast deposits of greensand mixed with calcareous, fossiliferous. marine debris. Other types of hematite not vet mined commercially are in metamorphosed rocks-red ore in slates in Columbiana Mountain and specular hematite (gray ore) in quartzite in the Talladega Hills.

Jan 1, 1938

EUGENE COSTE, ? Calgary, Alta.-Evidently in Argentine they have a petroliferous province just east of the Andes where very much the same conditions exist as are found on the east side of the Rocky Mountains and in the plains adjacent. It strikes me, though, that the same mistake is being made in Argentine in the exploration for oil as was made in Alberta, Canada; viz., drilling the wells too .near the seepages in the belt in the eastern part of the petroliferous province, too near the mountains. This same mistake was made in Alberta, with disastrous results; viz., only fissure production was found. The strata so near the mountains are tilted at a very strong angle, such as is described in this paper, and the dislocations are intense. On the other hand, we have found that when we get 100 or 200 mi. away from the mountains we get into oil and gas belts which are very prolific. So far our fields in Alberta have been gas, but in Wyoming, as you know, they get many thousands of barrels a day. I have no doubt that conditions in Argentine are exactly similar but that they have so far kept too near the mountains and that they want to explore the belts farther east to obtain better results.

Jan 4, 1919

By Eric S. Cheney

The often-heard question "How can we interest young geologists and engineers in AIME?" is virtually the same as "How can we interest young geologists and engineers in the glamorous mining industry?" Many persons would reply that AIME and industry should improve their image by various devices aimed at high school students and teachers, boy scouts, and even grade school children. For more immediate results, I suggest that we concentrate our efforts at the professional level on students already identified as geol¬ogists and engineers. Why does our glamorous profession appear distinctly unglamorous to most of the engineers and geologists currently in college and graduate school? The answers seem quite simple to me. First, the profession talks almost exclusively to itself, seldom to the engineering or geologic public, and almost never to the lay public. Second, the industry has been overly conservative in all aspects of recruiting during an especially competitive and affluent period. Consequently, mining has taken a terrific public drubbing from preservationists who still portray its leaders as robber barons. SME and AIME have, of course, various commendable programs for enticing student interest, including student membership, the low dues for this membership, the somewhat reduced prices at which students can attend AIME meetings and buy AIME volumes, and the large number of AIME Student chapters on campuses. Obviously, more active encouragements are needed.

Jan 1, 1971

Jan 1, 1955

By AIME AIME

PAST President R. C. Allen, then State Geologist of Michigan, gave George Corless his first job-tracing ?magnetic? with the dip compass in northern Wisconsin. His second job was also with a man now Past President of the Institute-"Chief" Buehler, for whom he worked at Joplin three years. Then came seven years as geologist and later as assistant manager of the Chanute Spelter Co., a subsidiary of The American Metal Co., Ltd. His entrance into the oil business was not planned. During a lull in the zinc industry in July, 1926, he stopped at Houston, after a trip to the Rio Grande Valley, and was so impressed with the city that he decided to migrate. His first job there was with the Texas Company, whose impressive building across from the Post Office caught his eye after he had mailed a letter saying that he was settling in Houston and would not be home until Christmas. Some months later, A.I.M.E. Past President Philip N. Moore learned that he was in. Houston and wrote an unsolicited recommendation that resulted in his present employment with the Humble Oil & Refining Co. Today he is superintendent of the Gulf Coast Division of its production department. The Division extends from Jackson County, Texas, to New Orleans, and includes such pools as Sugarland, Conroe, Toni Ball, Thompsons, Anahuac, and Friendswood. -

Jan 1, 1938

By J. B. Hiskey

The hydrometallurgical application of thiourea in processing precious metal ores and concentrates has reached the development stage. This paper reviews recent technical literature covering the process development of thiourea leaching. In addition, recent fundamental contributions are discussed. Most of the interest in thiourea leaching has involved treating high grade concentrates that have sufficient value to just the use of thiourea as a reagent. An important development in thiourea technology is the addition of SO2 to the leaching solution. This procedure effectively reduces the decomposition of thiourea and eliminates the problems of passive surface layers that limit the leaching efficiency. Results for the thiourea leaching of a bulk sulfide concentrate and a residue from the autoclave leaching of a smelter flue dust are also reported. As determined by a standard bottle roll cyanidation test, the bulk concentrate was extremely resistive to cyanide leaching yielding only 16% gold and 2% silver extraction in 24 hours. Leaching with a relatively concentrated thiourea solution (1MCS (NH2)2) resulted in 83% gold and 75% silver extraction in four hours. With the treated flue dust residue, gold extraction was about 60%. Gold and silver extraction with cyanide was sensitive to both cyanide concentration and oxidizing conditions. Cyanidation resulted in 59% gold extraction and 77% silver extraction in 24 hours.

Jan 1, 1985

FOREIGN WAR RELIEF COMMITTEE Chairman, MRS. JESSE SCOBEY The task of the committee since Oct. 17, 1918, has been to stimulate and foster interest in the work of the Dispensary in France, to aid and further the work, and to that end has centered on the inauguration of an "Engineers' " day, once a week, at the headquarters of the American Fund for French Wounded, where members of the Auxiliary might join in sewing for this "Dispensary of the New York Section of the Woman's Auxiliary to the A. I. M. E.," recently established at Briey, France. Letters and pledge forms asking for workers were sent to all members of the Auxiliary in New York City and vicinity, and a most gratifying response has assured the success of the undertaking. The meetings in December, pending the completion of better working facilities at Fund headquarters, were held at the home of Miss Madeline P. Stone, to whom the committee extends its grateful thanks for her hospitality large, well-equipped room at Fund headquarters has now been assigned to the committee for Tuesday of each week, from 10 a. m. to 5 p. m., with Mrs. Percy E. Barbour of the committee as director of work room. All members of the Auxiliary and others whose interests are with the mining profession will be welcome on "Engineers'" day-Tuesdays-at 73 Park Ave.

Jan 2, 1919

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons introduced by members.) Engineer of many years' experience in mining engineering, construction, public works, contracting, water-power development and operation, having heretofore retired on a sufficient competence, wishes to have employment with thoroughly reputable concern where his experience would be of value; the question of remuneration is of secondary importance. A-2591. Engineer, in military service nearly two years, desires, when discharged, to secure permanent position offering future opportunities. Experienced as mechanical and metallurgical engineer, investigator, teacher. Technical graduate and post-graduate from two of best American schools. Ability as executive, organizer and industrial leader. Especially fitted for industrial position of administrative nature or as technical assistant to industrial manager. Salary expected $4500 to $5000. A-2619. Member A. I. M. E., age 36, twelve years' experience in smelting and hydrometallurgy of copper ores, desires research or works position with responsible company. Speaks fair Spanish. Can handle men. Will welcome difficult metallurgical problems. Salary $5000. A-2627. Mining engineer, recently discharged from the Army as Captain, Engineers, age 38, 15 years' experience in the Southwest and in Mexico in gold, silver and copper mining, engineering, surveying, sampling and assaying, with special training in prospect and mine examination and the development of prospects. Speaks Spanish; immediately available; references. A-2136.

Jan 6, 1919

THIS method of melting with a little wind furnace is called by many melting with air. It is a method that is done with little labor. First a furnace is made with crucibles and charcoal. It is small or large as you wish, without blast from bellows, but not without a draft of air which proceeds from the place where it is made and from the arrangement of the furnace.* This, after a certain period of time, has the effect of melt- [ ] gin the thing in the quantity that you wish, provided, however, that you proportion it properly to the space, to the fire, and to the air which makes the wind. In order to make this, the aforesaid furnace is first made of bricks, or it is dug out of an elevation of stone or [106V] in a wall of clay. It can also be made portable with iron bars and loam as I shall tell you. However you may make it, you must place it in a spot that is windy, for instance, in some large room or opposite doors or windows. It is made round or square as is most pleasing to him who is to make it. But here we will now say that it is to be made square for greater convenience of building with bricks. Having chosen the place, make it a half

Jan 1, 1942

The first prize of the President's Prizes has been awarded to J. J. Beeson for his paper entitled "Disseminated Copper Ores of Bingham, Canyon." When this paper-was written, Mr. Beeson was a student at Stanford University, and was president of the Stanford Geological and Mining Society. The President's prizes were established in 1915, funds being provided, at that time for three prizes of $50, $30 and $20 respectively, for the best essays, or other papers submitted in competition by Junior Members and Members of Affiliated, Student Societies. The original intention was to award all three during the year 1915, but the committee has deemed it advisable to extend the time for the second and third prizes, and the Secretary of the Institute will be glad to hear from any member who wishes to compete for one of these prizes. A competitor for the President's Prizes must be, at the time of submitting his essay, either a Junior Member or a Member of an Affiliated Student Society of this Institute. The essays must be upon some subject related to Mining, Economic Geology, or Metallurgy. I11 malting the awards, special weight will be given to originality in investigation and treatment; and to 'literary merit. As a general rule, the essays should not be less than 3,000, nor

Jan 5, 1917

By D. W. Fuerstenau

MEASUREMENT of zeta potentials is a useful tool to study the surface chemistry of minerals under flotation conditions.1,2 Because there is continued interest in this approach, the apparatus for obtaining zeta potentials of nonconducting solids by the streaming potential method is outlined here. Fig. 1 illustrates the streaming potential apparatus." The streaming potential cell or plug consists of two 24/40 standard ground joints (4) joined with a piece of pyrex tubing 60 mm long and 12 mm in diam (5). The electrodes are made of bright platinum disks 19 mm in diam and 1 mm thick through which 0.5-mm holes have been drilled (6). To the surface of each is welded a piece of 80-mesh platinum gauze. Each electrode is permanently mounted on the ends of the inner parts of the two standard joints by means of a platinum wire (7) which connects it to the tungsten seal at the end of the cell (8). For ease in cleaning and handling the apparatus, the streaming cell is fastened to the 500-ml reservoir flasks (1) by means of two 18/9 ball and socket joints (2). This particular arrangement permits passage of the solution in either direction through the plug of particles. Flow of solution can be stopped by a stopcock (3). One of the reservoir flasks has a large opening to permit insertion of either a thermometer or a pair of electrodes for measuring pH of solutions within the system. In making the experiments, the plug is filled with 48 to 65-mesh particles, but a layer of 28 to 35-mesh particles is placed at each electrode to prevent any of the finer particles from passing through holes in the electrodes. The assembled apparatus is shown schematically in Fig. 2. To eliminate CO2 from the solutions, all experiments are conducted in a nitrogen atmosphere. Nitrogen, used to drive solutions through the plug, is passed through a bottle of concentrated KOH solution to remove CO2 (9). A 9-liter ballast reservoir (10) is used to maintain a more nearly uniform pressure. A series of stopcocks controls the direction of flow nitrogen to the flasks (11). Tubes of as-carite prevent backflow of CO2 into the system (12). Driving pressure, which can be set at any desired value, is measured with either a water manometer (13) or a mercury manometer (14). Reservoir flasks have side arms for making pressure corrections for the difference in water levels in the flasks. Streaming potentials are measured by the circuit illustrated in Fig. 2. The electrodes from the plug are connected through mercury wells (15) to a reversing switch (16), which reverses the polarity of the electrodes depending on the direction of flow of solution through the plug. The streaming potential is measured with a Leeds and Northrup type K2 potentiometer (17). Proper choice of null instrument is important because Eq. 1 assumes that the current which escapes through the measuring instruments is negligible. An ordinary galvanometer cannot be used to determine the null point because

Jan 1, 1957

By J. O. Betterton, W. M. Spicer

The solubilities of antimony in the a and ß-forms of zirconium were determined between 750" and 1300°C. The a-phase forms by a peritectoid reaction, and the a/(a + ß) and ß/(a + ß) phase boundaries rise in temperature with in- ' creasing antimony. Impurities in the 99.95 pct zirconium were sufficient to influence the phase boundaries and the variation reported is approximate. The restricted solid solubility of the terminal zirconium phases, which is especially characteristic of this system, is thought to result from the low free energy of the Zr2Sb phase. ZIRCONIUM-antimony alloys are important in zirconium alloying studies since antimony is one of the highest valent elements which can be used to make zirconium alloys. The dilute alloys are of further interest as they have somewhat better corrosion resistance' than pure zirconium. The first investigation of the phase diagram was made by Russi and wilhelm2 who found a eutectic reaction, liquid (- 17.5 at. pct Sb) = ß zirconium (- 11 at. pct Sb) + Zr2Sb, at 1430°C'. The Zr2Sb phase was of complicated hexagonal structure, and by thermal analyses of the relatively impure alloys then available, Russi and Wilhelm found evidence for the peritectoid formation of the a-phase. EXPERIMENTAL In the present work, the phase diagram was re-investigated in the region 0 to 5 at. pct Sb and 750" to 1300°C using iodide-zirconium alloys. Details of the procedure have been described earlier. Essentially the alloys were prepared by arc casting and were then examined by the annealing and quenching method. The times of annealing varied from 1 hr at 1300°C to 30 days at 760°C. As in other zirconium phase-diagram studies1"5 the impurities in the zirconium were still sufficient to affect the results, and the experiments will therefore be described in 3 parts. The results from the first 2 parts of the work are shown in Fig. 1. Here the ß/(ß + Zr2Sb) and a/(a + ZrzSb) phase boundaries were determined with alloys made from 99.9 pct zirconium,* and cast under such conditions that the Vickers hardness of a alloys extrapolated to 95 to 110 VPN at 0 at. pct Sb. Such alloys were not suitable for investigations of the (a + ß) region, and the results shown in Fig. 1 near the (a+ ß) and (a +ß + Zr2Sb) regions were determined with purer alloys. These alloys had an extrapolated hardness range of 75 to 85 VPN and were made from 99.95 pct zirconium. A deviation from binary equilibrium occurs in Fig. 1 as indicated by the (a + ß) region of pure

Jan 1, 1959

By W. G. Woolnough

Production of oil in Australia is negligible at present. A very small quantity of crude is being recovered from lean pumpers in Victoria, and a little activity is evidenced in Queensland, where two new wells were sunk during 1934. One of these, at Warooby Creek near Roma, obtained a noteworthy gas flow, but no oil production has been recorded. Geological investigation is going on in Western Australia, but no drilling activity is apparent. The "boom" in oil prospecting came to an end when the wave of depression swept over the country, and the investing public turned its attention actively towards gold. There is great activity in gold prospecting at present. I still maintain as strongly as ever that the prospects of obtaining flow oil in Queensland, Western Australia and Victoria are good, and that really scientific methods must ultimately succeed. Active and excellent geological work is being carried out in the Mandated Territory of New Guinea, and it is reported that drilling is likely to be undertaken next year. Matters in Papua are at a standstill. The question of extraction of oil from the oil shales of New South Wales and Tasmania is perennially active, and attempts to exploit this source commercially are renewed from time to time. Hydrogenation of coal is also receiving a good deal of attention.

Jan 1, 1935

By F. L. Grammer

In these day, when anthracite is less extensively used as a blastifurnace fuel than it was a generation ago, and managers endeavor to maintain regular and known ore-mixtures, the " freezing " of tuyeres, cinder-notch or iron-notch is infrequeut; and, consequently, the oil-burner or " kerosene blowpipe "* is seldom employed; and furnace-foremen have, to a considerable degree, forgotten their former cunning and persistency in the use of the drill and sledge. Still, in starting new or abandoned plants with untrained labor, and in running some of our large 100-ft. furnaces, slips, resulting in very cold furnaces, may occur, even under experienced managers. During my superintendence of the Cleveland, O., blast-furnaces, such a misfortune, owing to a dearth of trustworthy foremen, was experienced; and our electrician, Mr. Thomas Martin, proposed to open the tuyeres and cinder-notch by means of the heat of the electric arc. We have heard that the surface-cracks or marks developed in rolling heavy plates have been closed by electric welding, as by a soldering-iron, and also that an electric burner has been employed at some German blast-furnaces; but the experiment was quite novel to us; and I think it constituted one of the first, if not the very first, successful application of this device, for the purpose named, in the United States. †

Jan 1, 1902

By R. D. Fisher, A. G. Metcalfe, F. A. Crossley

AN investigation of the application of magnetic stirring to the consumable arc melting of aluminum and nickel demonstrated that grain refinement could be obtained when there was sufficient stirring force. Also, it was found that grain refinement could be obtained in aluminum by alternately reversing the polarity of the current through the magnetic stirring coil. The effect of the latter was to periodically reverse the direction of rotation of the molten metal.' Because of their promise, these findings were applied to conventionally cast aluminum. Shortly after this work was begun, Kondic2 reported experiments in which aluminum cast with 40° C (72° F) of superheat exhibited a grain size of 10 to 20 grains per cm2. When interrupted rotation was applied during solidification by mechanical means, a grain size of 800 to 1000 grains per cm2 was obtained. Magnetic Stirring Applied to Conventional Casting— The applicability of magnetic stirring to producing grain refinement in conventionally cast metal was evaluated in the following way. Three pounds of aluminum were cast into a clay-bonded graphite mold. The mold was surrounded by a magnetic stirring coil of 1000 turns. A direct current of 200 amp was passed through the casting by means of a graphite electrode which was immersed from the top. A current of 5 amp was passed through the stirring coil. The aluminum (1100 or 25) was superheated to 1600° F (871° C) and fluxed by passing chlorine gas through the melt for 2 min prior to casting. Two additional castings were made for comparison: 1) a conventional casting of metal superheated to 1600° F and 2) a similar casting through which 200-amp current was passed during solidification, but without current in the magnetic coil. Macrosections of these three ingots are shown in Fig. 1. Very remarkable grain refinement resulted in the magnetically stirred casting. It may be noted that the casting through which 200-amp current was passed has a coarser structure than the conventional casting. It would appear that this is due to the additional heat input generated by the current to the former casting. Mechanical Rotation Applied to Conventional Casting—A casting temperature of 1600° F was used throughout. Some 1 1/2 -lb castings rotated at 150 rpm were predominantly columnar with small areas of coarse, equiaxed grains close to the lower mold wall. Following these, a series of 3-lb castings was made. Macrosections of these ingots are shown in Fig. 2. The imposed rotational speed was 250 rpm. Turbulence or acceleration in the solidifying liquid was the significant factor. Fine grain size resulted in the material solidified during the period of acceleration of the liquid to the imposed rotational speed. When uniform rotational motion was achieved, the grain structure reverted to columnar. The final casting shown in the lower right-

Jan 1, 1962

By G. V. Sullivan, B. E. Davis, T. O. Llewellyn

The Bureau of Mines, US Department of the Interior, conducted studies to recover phosphate from four dolomitic southern Florida deposits not currently mined. The samples contained 5.8-10.2% P205 and 1.7-4.8% MgO. Chemical analyses of sized fractions indicated that no pebble concentrate, +1.2 mm (+14 mesh) could be produced from these samples. A scheme was developed that consisted of desliming, grinding, scrubbing, and redesliming the ore to produce a flotation feed. Conventional one-step fatty acid fuel oil batch flotation tests on the samples resulted in concentrates containing 29.0-31.3% P205 at flotation recoveries ranging from 72.4 to 96.1% of the flotation feed. The MgO content of the concentrates ranged from 0.47 to 1.36%. Continuous flotation of the Manatee No. 2 sample indicated that commercial-grade phosphate concentrates analyzing 31.3% P205 and 0.55% MgO could be produced with a flotation recovery of 89.9%. The MgO content of concentrates obtained from the Manatee No. 1 and Hardee samples was 1.20 -1.36 %, respectively. Leaching with aqueous SO2 reduced the MgO content of these phosphate concentrates to 0.5 and 0.8%, but with a concomitant loss in phosphate recovery of about 10%.

Jan 1, 1985

By William C. Aitkenhead, John A. Jaekel

Uranium deposits in the Spokane Indian Reservation, as well as those around Mt. Spokane, are essentially low grade, much of the ore containing less than 0.2 pct U808. The Mining Experiment Station of the Division of Industrial Research, State College of Washington, has been engaged in intensive research on the amenability of these low grade ores to froth flotation. The results: successful flotation of autinite, chief mineral constituent. At the outset of this work the goal was a concentrate of 1 pct U308 with a 90 pct recovery from ores containing less than 0.2 pct U3O8. Most of the work has been done on argillite ore from the Midnight mine on the Spokane Indian Reservation. The goal has not been attained using this ore, but samples of the granite ore from Mt. Spokane yielded successful results. For example, a concentrate containing 11.2 pct U308 was produced from a Mt. Spokane high grade ore containing 1.27 pct U3O8 with a recovery of 97.8 pct. Another Mt. Spokane ore yielded a concentrate of 5.0 pct U3O8 from an ore containing 0.13 pct U3O8, with a recovery of 85 pct. This same ore gave a recovery of 93.5 pct when the grade of concentrate was reduced to 2.0 pct.

Jan 1, 1959

By John E. Young

U.S. Steel Corp.'s Winifrede mine is operated by Lynch District in the mountainous region of eastern Kentucky. This region is characterized by narrow finger ridges and precipitous slopes, which present both an opportunity and challenge in the design and selection of coal-handling facilities for the movement of coal from the section belts to the railrod cars. Lynch District selected diesel-powered locomo¬tives and 100-ton articulated cars capable of negotiating sharp curves. The drop¬bottom mine cars are equipped with longitudinally hinged doors that are auto¬matically opened and closed. Lynch District selected a large-diameter steel-lined borehole for lowering the coal approximately 1000 ft from the seam level to the valley floor railroad load-out point. Taking advantage of gravity, the presized coal is "lowered" vertically approximately 720 ft to existing entries of a previously abandoned mine. The coal is then conveyed horizontally into storage. The coal¬handling facility from the mine-car dump to the railroad load-out point is fully automatic through use of tone control. TV cameras are installed along the facility to continuously monitor the strategic points. The diesel locomotives are either directly operated or remotely radio-controlled, depending on the functions Per¬formed. U.S. Steel Corp.'s Winifrede mine is operated by Lynch District in the mountainous region of eastern Kentucky. This region is characterized by narrow mountain ridges and precipitous slopes which present both an opportunity and challenge in the design and selection of coal-handling facilities for the movement of coal from the section belts to the railroad cars. The narrow finger ridges precluded use of under¬ground haulage and, thereby, presented the opportunity to use high-capacity equipment on the outside bench. The precipitous mountain slopes, steepest at the Wini¬frede seam horizon, presented a challenge to select a solution for lowering the coal approximately 1000 ft from the seam level to the valley floor railroad load-out point. It was evident from the start of planning that these two factors predominated; namely, rail haulage and coal lowering, and solutions to these would determine the final design of the Winifrede mine coal-handling facilities. The Winifrede mine derives its name from the Wini¬frede Seam which comprises the total reserve recov¬erable from this facility. The seam is 5 ft high with a good siltstone bottom and competent shale or sandstone roof. The seam is at an elevation of 2700 ft where the mountain ridges are long and narrow. This configuration of the reserve was ideal for conveyor belt installation to transport the coal from the working face to the outside bench. The preclusion of underground rail haul¬age permitted an opportunity to review the type of locomotive power and to select high-capacity equipment without the limitations associated with underground systems. Since the basic electrical design of the mine was al¬ternating current, with rectification to direct current for shuttle cars required only in the face areas, there was no point in bearing the burden of additional cost of dc trolley installation. And, since the haulage would re¬quire only a few tunnels to negotiate sharp points and to reach the back side of the reserves, diesel power was selected for the haulage locomotives. To provide stability on the almost continuously curv¬ing track and to provide the maximum width of haul¬age equipment, both locomotives and mine cars, stan¬dard railroad gage was chosen to offer the largest choice of equipment. The decision was made to select a standard 45-ton railroad diesel locomotive but to lower the cab height to reduce tunnel excavation requirements. The mine car was the next challenge. Past experience in Lynch operations indicated that drop-bottom cars would be a successful application with the free-flowing coal. The search was for a drop-bottom car within the dimensions of the locomotive to discharge the coal in the shortest time. Numerous types were considered and visits made to various sites to observe cars in operation.

Jan 1, 1972

By C. L. HUSTON

MY ANCESTRAL connection with the manufacture of boiler plate runs back through four generations, and my personal acquaintance with the practice reaches back to the time, in my ,boy- .hood days, when iron plates' were made in a mill operated entirely by water power. -The mill originally was driven by an old-fashioned "'breast" water wheel 20 ft. in diameter and with a20-ft. face, geared direct to the roll train. When the mill slowed up and there was danger of its stalling, the men would jump upon the rim and help the wheel around with their weight, to prevent a "sticker." Later, as large plates were called for, a flywheel was set out of line so that it could' be speeded up by gears from the water wheel and connected back again,. by reducing- gears, to the roll train. The flywheel, with its cast-iron rim and wooden spokes, made 90 r.p.m. and the roll train 45 r.p.m. In 1870, our company installed our first steam-driven plate mill two-high rolls, 84 in. long. In these early mills the hot metal was manipulated by hand.

Jan 1, 1920