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The Mine Safety and Health Administration (MSHA) defines an independent contractor as “any person, partnership, corporation, subsidiary of a cor-poration, firm, association or other organization that contracts to perform services or construction at a mine.” Contractors that perform specific types of work are required to report the number of employees who work at coal mines and noncoal mines.

Sep 1, 2007

By F. P. Haver

The Bureau of Mines developed a process to extract about 90 percent of the sulfur from molybdenite flotation concentrate by compacting the concentrate with one-quarter of its weight of aluminum powder, heating it at 800° C for 30 minutes, and then allowing the product to react with water. This thermite reduction yields an impure molybdenum alloy plus aluminum sulfide. The latter readily hydrolyzes, to yield pure hydrogen sulfide which can be converted to elemental sulfur by the Claus process. At least 95 percent of the molybdenum can be subsequently recovered as 99.95-percent-pure molybdic oxide.

Jan 1, 1968

By P. A. Wasson

Drill cores from 15 holes in the West Central Mesabi Range were studied as part of the Lake Superior iron resource investigation begun in 1957 by the Bureau of Mines. Chemical, petrographic, and metallurgical analyses were made to determine grade, mineralogy, magnetic characteristics, and response to beneficiation. Data in this report were developed to provide a better under-standing of the nature and character of low-grade iron ore occurrences, to measure potential of usable ore, and to provide a basis for comparison with bank samples previously taken in the same general area. The average iron content of 4,445 feet of core was 31.8 percent. Iron oxides present were hematite, goethite, and magnetite; the gangue minerals were chiefly quartz, iron silicate, and iron-bearing carbonates.

Jan 1, 1962

By George A. Morgan

The production and processing of crude petroleum and natural gas are the dominant economic sectors of the Middle East. The 15 countries that constitute the region accounted for 28% of world crude petroleum output, 17.2% of world natural gas plant liquid production, and 5.3% of world dry natural gas production. Only Cyprus and Lebanon were not crude petroleum producers. About 66% of total world crude petroleum reserves and 31 % of total world natural gas reserves are in the Middle East. Transportation and port facilities in the region are geared to expediting efficient and rapid shipment of these materials. Export sales of these fuels provide funding for further diversification of the mineral industry. Additional development of downstream facilities for producing energy-intensive metals such as aluminum and byproducts of the fuels such as petrochemicals and fertilizers can be expected. Earnings from the industry are also channeled by several Governments in the region to mineral industry projects in Africa and elsewhere. Several countries in the region own major petroleum refineries and distribution facilities worldwide. Petroleum prices rose overall during the year owing to the invasion by Iraq of Kuwait in August 1990. Output from both countries, the fourth and fifth largest producers, respectively, in the Middle East, was negatively affected by the war. Kuwaiti crude oil wells and pipeline facilities suffered extensive war damage while exports of petroleum and petroleum refinery products by Iraq ceased owing to a U.N. embargo. The embargo also impacted Jordan, an exporter of phosphate and potash. Shipments of crude petroleum by pipeline from Iraq through Saudi Arabia and Turkey and by vessel through the Persian Gulf were terminated. However, the loss in production from Iraq and Kuwait was more than made up by accelerated output from other Middle East and world producers. Saudi Arabia, in particular, with its excess production capacity, accounted for the largest portion of the increase.

Jan 1, 1992

By Ronald D. Hill, Elmore C. Grim

1.In 1972 over 595 million tons (51+0 million metric tons) of bituminous coal were mined; 49% of this tonnage was obtained by surface mining methods. Authorities have predicted that the tonnage of surface mined coal will increase in the future, especially since oil and gas resources are becoming limited. 2. Demands for clean air have increased mining activities in the low-sulfur coal deposits in the West. Pollution problems arising from these operations will be considerably different than those found in the East. The deposits are located in arid to semi-arid regions. Coal seams are generally aquifers and are a principle source of fresh water. Therefore mining may result in alteration of groundwater distribution patterns by aquifer disruption. In general, pollution problems associated with western mining are not well characterized. 3.Since any disturbance of the surface will alter the environment in the vicinity of the disturbance, pre-mining planning is a prerequisite to any environmentally successful surface mining operation. If properly carried out, the adverse social, economic, and environmental effects of coal surface mining will be minimized. Certain land areas will be unsuitable for surface mining where: a.Reclamation is not physically or economically possible. b.Mining is incompatible with existing land use plans. c.The proposed mining area is of critical environmental concern. Core drilling is the most satisfactory method of obtaining accurate information for pre-mining planning. 4. Unaccountable strip mining in the past has created problems that are still present today. Contour mining methods that involve the indiscriminate dumping of overburden on the downslope is one of the largest single sources of sediment from strip mining. However, land disturbed by strip mining can be reclaimed. Techniques have been and are being developed by which mining and reclamation are integrated into a single operation. Mountain top removal, head-of-hollow fill, and block cutting are examples in contour surface mining. These methods drastically reduce pollution problems associated with contour stripping.

Jan 1, 1974

By P. R. Bremner

In keeping with its mission to maximize mineral and metal recovery from domestic sources, the Bureau of Mines investigated a method to extract silver from tailings not amenable to cyanidation. Results of a laboratory study on the recovery of silver from cyanide tailings containing 1.7 ounces of silver per ton by leaching with an acidic ferrous chloride-sodium chloride solution are presented. The effects of reagent concentration and reaction time on the leaching of silver were investigated. A leaching solution containing 5 wt-pct NaCI, 2.5 wt-pct FeCI2, and 1.2 wt-pct HCI (for acidity) extracted 82 pct of the silver from the tailings during a 24-hour leach. The amount of HCI consumed during the leach was 46 pounds of HCI per ton of feed. Only 23 pct of the silver was extracted by conventional cyanidation. Ninety-nine percent of the silver was recovered from the pregnant solution by cementation onto iron powder.

Jan 1, 1982

By Lloyd A. Morley, Alan M. Christman

1. Anonymous. "Getting Down to Earth," booklet 25T, James G. Biddle Co, Plymouth Meeting, Pa. (1970) pp. 1-48. 2. Anonymous. "Megger Ground Tester, Special Instructions," booklet 25-J-1, James G. Biddle Co, Plymouth Meeting, Pa. (1961) pp. 1-16. 3. AIEE Committee. "Application Guide on Methods of Substation Ground¬ing," AIEE Transactions on Power Apparatus and Systems (April 1954) pp. 271-277. 4. AIEE Committee. "Voltage Gradients Through the Ground Under Fault Conditions," AIEE Transactions on Power Apparatus and Systems (October 1958) pp. 669-692. 5. American Standards Association. "American Standard Safety Rules for Installing and Using Electrical Equipment in and about Coal Mines," U. S. Bureau of Mines Information Circular 8227 (1964). 6. Armstrong, H. R. "Grounding Electrode Characteristics from Model Tests," AIEE Transactions on Power Apparatus and Systems (December 1953) pp. 1301-1306. 7. Beck, Edward. Lightning Protection for Electric Systems, McGraw¬Hill, New York (1954) pp. 281-295. 8. Bellaschi, P. L. "Impulse and 60 Cycle Characteristics of Driven Grounds," AIEE Transactions (March 1941) pp. 123-128. 9. Bellaschi, P. L. "Lightning Strokes in Field and Laboratory," Elec¬trical Engineering, Vol. 58 (November 1939) pp. 466-468. 10. Bellaschi, P. L., Armington, R. E., and Snowden, A. E. "Impulse and 60 Cycle Characteristics of Driven Grounds-II," AIEE Tran¬sactions (1942) pp. 349-363. 11. Bewley, L. V. "Theory and Tests of the Counterpoise," AIEE Transac¬tions (August 1934) pp. 1163-1172. 12. Brereton, D. S. and Hickok, H. N. "System Neutral Grounding for Chemical Plant Power Systems," AIEE Transactions on Applica¬tions and Industry (November 1955) p. 315. 13. Bruce, C. E. R. and Golde, R. H. "The Lightning Discharge," Journal of the Institute of Electrical Engineers, London, Vol. 88 (December 1941) pp. 487-505.

Jan 1, 1976

The notion of wayfinding, as conceptualized by planners, geographers, and psychologists, denotes the ability of an individual to move from one point to another through physical space. In order to achieve this movement, a person relies on a cognitive map of spatial representations [Passini 1984]. Which features of this cognitive mapping will be stressed depend, in part, on the researcher's perspective. A planner, for instance, would tend to emphasize the effect of physical structures on mobility. A psychologist, on the other hand, might focus on individual differences in how human minds encompass and represent physical space [Evans et al. 1984]. There is yet another dimension to wayfinding that needs consideration, and it rests upon the idea that reality, as experienced by human beings, is mediated: "[People] have preselected and preinterpreted this world by a series of commonsense constructs ... which help them find their bearings in their natural and socio-cultural environment and to come to terms with it" [Schutz 1967]. These "common sense constructs" are arrived at socially and constitute the agreed-upon schemas that guide people's everyday activities. According to this principle, cognition is governed by some nonlogical factors that reflect not only individual procedures but collective ones as well. These group strategies, which are shaped by shared rules and values, influence "the information gathered, the ways it is processed, the inferences that are drawn, the options that are being considered, and those that are finally chosen" [Etzioni 1992]. From this perspective, cognitive maps, rather than being individual-centered templates of environmental images [Rovine and Weisman 1989] or representations of spatial relationships [Evans 1980], are partially group-centered schematic processes. As such, they are subject to reinterpretation, revision, and outside intervention [Kaplan and Kaplan 1982]. As intermediaries between the environment and behavior, cognitive maps serve as bases for decision-making. Traditionally, it has been assumed that good maps facilitate correct decisions, which in turn leads to optimal performance during wayfinding [Hunt 1984]. Given the argument that there is a social (non¬cognitive) facet to cognitive mapping, however, this image of a cognitive map as some sort of static reference construct that motivates individual action is too narrow and mechanistic. If cognition involves less a knowledge of the environ¬ment than it does the process of "giving it meaning through imposing an order on it" [Rapoport 1976], then wayfinding behavior is not j ust a function of setting and individual differences, but is also a function of one's "normative-affective" structure [Etzioni 1992]. Rapoport [1976] used such an assumption as the base for a set of hypotheses about the connection between "external demands" and "organismic factors." One significant assertion deriving from Rapoport's ideas is that environmental

Jan 1, 2000

By Gerrit V. R. Goodman, Jeffrey M. Listak, John A. Organiscak

Data on dust control practices, geology, and occupational exposures were gathered for approximately eighty underground continuous mining units. Despite silica contents in excess of 5%, nearly forty units successfully maintained silica concentrations at or below 100 µg/rn3 on a majority of occupational dust samples while the remainder had difficulty maintaining this level. These two sample sets were termed group A operations and group B operations, respectively. Analyses of productivities, geologies, and dust control parameters revealed only minor differences between these two groups. Subsequent analyses of face ventilation design showed considerable differences in silica exposure and silica content between group A and group B at the continuous mining machine and roof bolter operator occupations. These differences were minimal when using exhaust curtain ventilation with a dust scrubber', This face ventilation system may benefit operations having difficulty controlling silica dust exposure and silica dust content. Finally, the collected data showed that occupational samples from group B operations possessed generally higher silica exposures and silica content than similar samples from group A. The single head roof bolter (helper) possessed among the highest silica exposures and silica contents in both groups.

By Stephen L. Tillim

Tubular Handles can negatively affect the contents of the carpal tunnel. Years of injuries from grasping handles for tools and machines can cause carpal tunnel syndrome, tendonitis and wrist joint injuries. The can cause inability to use a hand and resulted in the longer absences from work than injuries from falls, accidents or fires.1 Cylindrical, tubular and rectangular handles are rolled flat structures. They place the hand on a rolled flat surface where the ends of the middle and ring fingers overlap the index and small fingers. They are pulled along a series of lines that contact the end joint of the index finger, the middle bones of the middle and ring fingers and the end bone of the small finger. Cylinders are pulled diagonally in the hand toward the carpal tunnel (CT) area. Gripping in this manner tenses asymmetric muscle groups in the forearm. Handles could work better if they do not place pressure on the CT and conform to the natural function or neutral hand position where the hand rests or dangles at the side of the body, the finger tips form a diagonal, the palm and fingers form a cup, the thumb rests between the index and middle fingers and the wrist is mildly extended. However, handles designed for the neutral position are pulled by diagonally oriented fingers into the valley between the thenar and hypothenar muscles where they can compress the median nerve and tendons exiting the CT. Seven principles for handles that do not place pressure on the carpal tunnel and employ optimal hand position are presented. First, handles should align the ends of the fingers parallel to the horizontal crease and not diagonally. Second, handles should extend from the cupped fingers to meet the muscles at the base of the thumb on the radial side of the hand and extend further on the other or ulnar side to meet a portion of the small muscles. Third, handles should have a recess on the proximal side to prevent contacting or placing pressure on the carpal tunnel. Fourth, handle design should be based on hand measurements in a position of function. Fifth, handles should come in sizes. Sixth, handles should be placed on tools to maintain the wrist and elbow in neutral position. The seventh is handles should support the maximum area of the hand and absorb, but not direct, vibration to the carpal tunnel. These principles led to prototypes and patents for handles for gripping, pinching and squeezing2,3,4 . The poster will illustrate and explain the principles Bonsil handles. Research, with existing tools, is needed to substantiate claims made for the Bonsil handle.

Jan 6, 2006

By C. I. Pierce

The Bureau of Mines conducted laboratory tests to determine if ultrasonic energy could reduce either the residual water or oil content of petroleum reservoir-rock samples from Appalachian area oilfields. Brine-saturated core samples were flooded with oil to residual brine saturation and subjected to 20 kilocycles per second ultrasonic energy. Then they were flooded with brine to residual oil saturation and again subjected to ultrasonic energy. Additional water displaced as a result of the application of ultrasonic energy to the flow system ranged from 0 to 4.3 percent of the original brine and averaged 1.9 percent. The increase in oil recovery as a result of the ultrasonic energy ranged from 0 to 9.0 percent of the original oil and averaged 3.1 percent. On the basis of the tests, it appears that 20-kcps acoustic waves would not have field application for oil recovery.

Jan 1, 1968

Acid pollution from abandoned mines causes serious contamination of major streams in coal mining areas. In Pennsylvania alone it is estimated that 3000 miles of streams are devoid of fish and plant life because of coal mine effluent.1 The pollution arises because water and oxygen react with iron sulfide in the mine cavity to produce sulfuric acid and iron sulfate, which later find their way back into surface streams. Two general approaches to the problem are possible: (1) prevent the acid-forming reaction from taking place, (2) treat the acid mine water after it is formed so that it will not be harmful to the ecology when discharged into streams and other surface waters. The work described in this report belongs in the first category - it was based on the assumption that acid formation in the mine cavity can be prevented by keeping water (one of the reactants) out of the mine. This was to be accomplished by-forming a waterproof seal over the mine cavity which would prevent the seepage of surface water into the mine. It was planned to form such a seal at or near the surface of the ground by applying latex to the soil. Ideally a dilute latex would be applied to the soil and would penetrate to a depth of two to three feet below the surface where it would be coagulated by reacting with a constituent of the soil or by other means., A seal below the surface of the soil would have several advantages over a surface seal - it would not be subject to destruction by traffic, frost or vegetation and, more important, it would allow the use of the top soil for many agricultural purposes. A preliminary feasibility experiment was performed prior to application for the present grant. It showed that it was indeed possible to form a sub-surface seal by means of latex. A core of soil was obtained locally (Wayne, N. J.) by driving a 6.5 cm inside diameter steel pipe about 100 cm long into subsoil for a distance of 71 cm. The soil was retained within the pipe for this experiment. A part of the free space above the soil in the pipe was charged with water, and the seepage rate of the soil after it had become saturated was 15 ml/min under a total head (wet soil plus supernatant column of water) of 92 cm. After the supernatant water had drained completely, 100 ml of 5% rubber latex was added and allowed to seep into the soil. This was followed by additional water and the seepage rate was found to be 2 ml/min under the same head. This seepage rate remained unchanged when remeasured on the following day. Since there was no visible evidence of the latex in the collected drain water it is presumed to have been retained by the soil.

Jan 1, 1972

By Liming Yuan

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Jan 1, 2009

By J. Torma-Krajewski, M. Lehman

In 2005, NIOSH and Badger Mining Corporation entered a partnership to implement ergonomic interventions, including a systematic process, to address exposures to risk factors that may result in musculoskeletal disorders or other types of injuries/illnesses. As a result of this partnership, an ergonomics process was integrated with the existing safety and health program to promote an on-going application of ergonomic principles, and over 40 task-specific interventions were implemented during the first year of the process. This paper presents details of the process integration, and several examples of task-specific interventions that reduced exposures to risk factors.

By H. Billmayer

This report covers the period from June 17, 1974 to February 20, 1975, and describes the work performed in compliance with the requirements of Contract No. H0346102 and Modification No. 1 thereto. The purpose of the contract was to design protective canopies for an Elkhorn Scoop, a Lee Norse Miner, a Wilcox Miner and a Wilcox Bolter; to construct mockups of the canopies; and to obtain machine operator evaluations of the canopy designs by assessing the mockups while installed on their machines in the mines. The overall program objective was to achieve protective canopy designs for the four machines which would be acceptable to the operators.

Jan 1, 1975

By R. Craig Smith

The Bureau of Mines conducted a study of production costs for the secondary lead industry and determined costs for present, pending, and proposed environmental legislation. Operating costs for smelters by capacity groups range from 16.8 to 19.6 ¢!lb of refined lead. Present regulatory compliance costs for these groups range from 2.2 to 2.4 ¢!lb. Pending compliance costs could add 3.5 ¢!lb of refined lead, and proposed regulations could add another 1.3 ¢!lb. The individual capital costs necessary to comply with pending environmental regulations are estimated to be $1.8 million for small smelters and $10.4 million for large smelters. Proposed regulations could require additional expenditures from $1.9 million for small smelters to $4.9 million for large smelters. These cost estimates, based on average 1985 dollars, indicate that pending and proposed legislation could add significantly to capital and operating costs of the secondary lead industry. These regulatory compliance costs may result in a loss of up to 40 pet of secondary lead production capacity.

Jan 1, 1987

By Thomas L. Chapman

The San Manuel is a deposit of low-grade disseminated copper ore. It was brought to the attention of the government in October 1942 through an application to the Reconstruction Finance Corporation for a development loan, supported by a report by Henry W. Nichols. Nichols' sampling of two outcrops containing copper silicate and his geologic map indicated that a minable body of copper ore might be developed. The Federal Geological Survey was requested to examine the property. The Survey mapped the geology in March 1943 and cut a few check samples, which substantially confirmed Nichols' sampling of the outcrops and a few shallow workings. The geologists of the Survey recommended some test drilling by the Bureau of Mines. The property was examined by the author and Wm. D. Hughes, associate engineer of the Bureau of Mines on March 22 and 26, 1943, and a preliminary drilling campaign was recommended. Five shallow churn-drill holes totaling 1,480 feet were put down under the supervision of Chas. A. Kumke, one of the Bureau's engineers, from November 23, 1943, to January 13, 1944. This work indicated that the deposit extended deeper than the 350-foot depth attained in the deepest hole and might have very considerable areal extent. Additional funds were allotted, and the drilling contract was extended twice to a final maximum of 17,000 feet with 2,000 feet maximum depth of hole. Drilling was continued by the Bureau of Mines until February 2, 1945, when 15,844 feet of hole had been drilled. The Magna Copper Co. took options on this and adjoining property in September 1944 and commenced drilling with two machines. It also engaged the two contract drills used by the Bureau after it stopped drilling. It exercised its options in August 1945 and organized the San Manuel Copper Corp. to operate the property. That company is continuing to explore the ore body with six churn drills. Thomas Lyon took options early in 1945 on holdings adjoining the San Manuel property on the east and is operating two churn drills. Exploration up to the completion of the last holes started by the Bureau of Mines indicated a block of ore 3,100 feet long, 400 to 800 feet wide, and 500 to 900 feet thick, and averaging about 0.8 percent copper. Subsequent drilling showed that the ore body extends considerably beyond this block. The axis of the ore body strikes about N. 61° E. Copper minerals are disseminated in hydrothermally altered quartz monzonite and monzonite porphyry. Ore outcrops in two small areas over the northeast part of the block. Elsewhere the copper-bearing rocks are capped by Gila conglomerate, which thickens toward the west and south. Drilling showed that the ore is in a thick, tabular body with a steep dip to the south. The ore body lies near the surface in the northeastern part of the block. The south side of the block is much farther below the surface than the north side. There the upper part of the copper-bearing rocks is lightly mineralized, so that the hanging wall of minable ore lies deeper than the base of the conglomerate cap, which thickens southward.

Aug 1, 1947

By Thoms L. Chapman

The San Manuel is a deposit of low-grade disseminated copper ore. It was brought to the attention of the government in October 1942 through an application to the Reconstruction Finance Corporation for a development loan, supported by a report by Henry W. Nichols. Nichols’ sampling of two outcrops containing copper silicate and his geologic map indicated that a minable body of copper ore might be developed. The Federal Geological Survey was requested to examine the property. The Survey mapped the geology in March 1943 and cut a few check samples, which substantially confirmed Nichols’ sampling of the outcrops and a few shallow workings. The geologists of the Survey recommended some test drilling by the Bureau of Mines. The property was examined by the author and W. D. Hughes, associate engineer of the Bureau of Mines on March 22 and 26, 1943, and a preliminary drilling campaign was recommended. Five shallow churn-drill holes totaling 1,480 feet were put down under the supervision of Chas. A. Kumke, one of the Bureau’s engineers, from November 23, 1943 to January 15, 1944. This work indicated that the deposit extended deeper than the 350-foot depth attained in the deepest hole and might have very considerable areal extent. Additional funds were allotted, and the drilling contract was extended twice to a final maximum of 17,000 feet with 2,000 foot maximum depth of hole. Drilling was continued by the Bureau of Mines until February 2, 1945, when 15,844 feet of hole had been drilled. The Magma Copper Co. took options on this and adjoining property in September 1944 and commenced drilling with two machines. It also engaged the two contract drills used by the Bureau after it stopped drilling. It exercised its options in August 1945 and organized the San Manuel Copper Corp. to operate the property. That company is continuing to explore the ore body with six churn drills. Thomas Lyon took options early in 1945 on holdings adjoining the San Manuel property on the east and is operating two churn drills. Exploration up to the completion of the last holes started by the Bureau of Mines indicated a block of ore 5,100 feet long, 400 to 800 feet wide, and 500 to 900 feet thick, and averaging about 0.8 percent copper. Subsequent drilling showed that the ore body extends considerably beyond this block. The axis of the ore body strikes about N. 61º E. Copper minerals are disseminated in hydrothermally altered quartz monzonite and monzonite porphyry. Ore outcrops in two small areas over the northeast part of the block. Elsewhere the copper-bearing rocks are capped by Gila conglomerate, which thickens toward the west and south. Drilling showed that the ore is in a thick, tabular body with a steep dip to the south. The ore body lies near the surface in the northeastern part of the block. The south side of the block is much farther below the surface than the north side. There the upper part of the copper-bearing rocks is lightly mineralized, so that the hanging wall of minable ore lies deeper than the base of the conglomerate cap, which thickens southward.

Aug 1, 1947

This Part is concerned with the theoretical study of UHF radio communication in coal mines, with particular reference to the rate of loss of signal strength along a tunnel, and from one tunnel to another around a corner. Of prime interest are the nature of the propagation mechanism and the prediction of the radio frequency which propagates with the smallest loss. Our theoretical results are compared with measurements made by Collins Radio Co. This work was conducted as part of the Pittsburgh Mining and Safety Research Center's investigation of new ways to reach and extend two-way communications to the key individuals that are highly mobile within the sections and haulage ways of coal mines.

Jan 1, 1974

By R. A. Guidotti

The Federal Bureau of Mines has studied the reaction of oxides of columbium, vanadium, and tantalum with ammonia in vertical, gas-solids reactors at temperatures ranging from 300° to 1,300° C with the goal of preparing nitride intermediates for subsequent preparation of the metals by a thermal-decomposition step. The best nitride conversions were obtained in nonmetal reactors. With Cb205, V2O3, and V205 , low-temperature maxima in reaction rates occurred at 800°,800°, and 450° C, respectively, during oxynitride formation (in A1203) at 1 atm of pure ammonia. Conversion of the oxynitride, in a second step, to the mononitride was optimum at 1,200° C for columbium and 1,050° C for vanadium. In the case of Ta205, the rate of reaction to form Ta3N5 (in a single step) was highest at 900° C, where the presence of up to 5 percent methane was found to be beneficial; improved results were obtained by conducting the nitriding in a rotary kiln. Optimum space velocities (in the vertical Al203 reactor) ranged from 5,280 hr-1 for Cba205 to 7,950 hr-1 for V203. Oxide particle size had little effect upon reaction rates. Under fully optimized conditions, products containing less than 1 percent oxygen were readily obtained in under 6 hours.

Jan 1, 1975