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By W. S. Wright

"INTRODUCTION The Ward copper deposit was brought to the attention of the Bureau of Mines in September 1943 by John J. Knob, 217 E. Penn Street, Long Beach, N. Y. At that time all Bureau of Mines work on Seward Peninsula was being directed to the exploration of deposits of tin, a metal high on the strategic list. It was not until September 1946 that the Bureau could make a preliminary examination of the Ward prospect.ACKNOWLEDGMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual investigative work, and prepares the final report. The Metallurgical Branch, Oliver C. Ralston, chief, analyzes samples and performs beneficiation tests.Acknowledgment is extended to Robert S. Sanford, acting chief of the Alaska division, under whose supervision all exploratory work of the Territory is conducted."

Aug 1, 1947

By John Gross

The Alaska Station of the Bureau of Mines has recently conducted tests on two tailings from black sand which had been treated previously at the Station. The results of this previous treatment have be on given in a paper entitled "Recovery of Gold from Black Sand by Classifier Concentration." The gold in these tailings was intimately united with quartz, and was so finely divided that it could not be detected with the naked eye, nor even by P&nn ing unless the material was ground. Its fineness is further shown by the assºy result, which reported only lz per cent of the gold content as "metallics", Wºorea's the assay of the original sand reported 36 per cent of the gold as "metallics." The fact that the gold was in such fine particles, closely united with quartz, precluded further recovery by amalgamation without grinding. On the other hand, the small content present, as well as the lack of grinding appliances at the placer mines of Alasia, made it necessary that the material be cheaply handled if at all. With these facts in mind the experiments described below were undertake.n.

Oct 1, 1920

By E. P. Youngman

Titanium ranks as one of the more abundant elements, is widely distributed, and occurs in concentrated form in numerous deposits. This substance was discoveres 140 years ago; but despite the efforts of metallurgists and chemists to find a place for it in industry, only within the last 10 or 15 years has the increased use of titanium pigments provided any extensive outlet for titanium ores. Even to-day titanium is confined to a few highly specialized industrial applications. The metal itself is now quoted regularly in trade journale, but scarcely yet can it be said that the production or use of the metal. has progressed very far beyond the laboratory stage. Ferroalloys containing the element were largely used for a time, especially in connection with the manufacture of Bessemer steel rails; but as American rail- ways adopted open-hearth rails in preference to Bessemer rails, the demand for the alloys in the rail manufacture gradually dwindled into insignificance. New outlets for ferrotitanium have been found in the steel industry; and the production of titanium alloys, both in the United States and in Europe, has increased in recent years. By far the largest use of titanium at the present time, however, is in pigments. The manufacture of titanium white began in Norway, but at present the United States is the leading producer. One of the two companies now operating in the United States is also the leading factor in European production. Although titanium occurs, in many minerals, the principal commercial sources are rutile (the natural oxide, Ti02) and ilmenite (iron-titanium oxide, FeO. TiO2). The latter is a coal-black mineral, but it is the one used in the manufacture of the titanium white of commerce, as well as in the manufacture of ferroalloys and arc-lamp electrodes. Rutile, the natural oxide, is not pure white and, being less common in nature, costs more; it is, therefore, reserved for use in the manufacture of titanium chemicals employed in relatively small amounts in dye works and bleacheries and for sundry minor purposes. This paper summarizes the titanium industry, with special reference to its economic aspects. It is offered as a survey of current trade literature and as a digest of material in the files of the bureau and is presented in response to numerous inquiries from prospective producers as to ways and means of exploiting deposits. (At present, much of the ilmenite consumed in this country comes from overseas, principally from British India..). A forthcoming circular, devoted to deposits of titanium-bearing ores, deals with foreign and domestic sources of supply.

Oct 1, 1930

By Paul M. Tyler, Amy B. CLINTON

The four elements fluorine (F), chlorine (C1), bromine (Br), and iodine (I) form the most intimate family in the entire system of elements and are grouped under the name "halogens" or salt formers (by derivation from the Greek). The first member of this family, fluorine, is the most chemically active element known; and fluorspar, and to a less extent cryolite, the chief sources of fluorine, are important commercial minerals. Fluorine occurs in nature chiefly in combination with sodium as common salt, but it also appears in other natural compounds in sea water, salt-well brines, and bedded deposits. In addition to common salt, various compounds containing chlorine (chlorides) have long been consumed by industry on a large scale, and within the last two decades that element itself has come rapidly into prominence as one of the leading industrial chemicals. Bromine and iodine, the two retaining members of the family, are less abundant in nature and less readily isolated and in consequence of their relatively high price have found few industrial uses, being consumed chiefly in medicine and in photography. Bromine, however, is now entering the industrial field to a considerable extent, due to the rapidly growing use of ethylene dibromide in anti-knock compounds for gasoline. The present paper is devoted to bromine and iodine, but in order to compre- hend the physical and chemical characteristics of these two elements (and hence their potential economic significance) it is convenient to consider them as members of the family series to which they belong. The family relationship of the halogens is illustrated by the following:4 (1) The similarity in the chemical and physical properties of the elements and their corresponding compounds is such that the prop- erties of any one member of the family can be said to summarize or rather to typify the properties of all the other members, although fluorine diverges a little in some of its properties. (2) The gradual transition of chemical and physical properties is such that if the elementa are arranged in order F, Cl, Br, I the variation in any particular property in passing from fluorine to iodine nearly always proceeds in the same order, and that is the order of their atomic weight. Taxing almost any property and comparing its magnitude in passing from the element fluorine to iodine, or from the fluorides to the iodides, a similar graiation will be observed. Thus, take the melting point of the cadmium, calcium, barium, sodium, or potassium salts, in degrees.

Nov 1, 1930

By W. W. Adams

"A recent paper prepared by the writer summarized the results of an analysis of the accident records of 34 metal mines for the calendar year 1925. The present paper summarizes the results of a similar analysis of the accident records of 59 coal mines for the same year. This summary is based upon reports furnished to the Bureau of Mines, Department of Commerce, by operating companies that par¬ticipated in the National Safety Competition of 1925.The purpose of the Competition was to establish the lowest accident-severity rate, thus showing the smallest loss of time from accidents in proportion to total number of man-hours worked. The reports covered all lost-time accidents that occurred during the year, that is, all accidents that disabled an employee beyond the day or shift on which the accident occurred. Detailed information for each of the 59 coal mines is given in the appended table. Each mine employed at least fifty men underground; over half of than employed more than 200 men underground. Hence the accident records should be typical of those of large-scale mining operations in general where the company is devoting special attention to accident-prevention work. The mines covered by the reports are situated in eleven States: Alabama, Illinois, Indiana, Kentucky, Maryland, Ohio, Pennsylvania, Tennessee, Utah, Washington, and West Virginia.A tabulation of the reports covering the 59 mines showed an accident-frequency rate of 123 per million hours of ""exposure* and an accident-severity rate of 10.214 per thousand hours of exposure3. The total volume of exposure or employment was 29,117,561 hours, representing the equivalent of work of 12,000 men for three hundred 8-hour shifts. The records covered employment and accident above ground as well as underground, although they did not include stripping or open-pit mining. Accidents during the year resulted in 33 deaths, 1 permanent total disability, 28 permanent partial disabilities, and 3,510 temporary injuries. These accidents represented a loss of tine equal to 297,417 man days. In arriving at this lost-time equivalent, each fatality and permanent total disability was weighted at 6,000 lost days (see footnote 3), as specified in the scale adopted by the International Association of Industrial Accident Boards and Commissions; permanent partial disabilities were weighted according to nature of injury, in accordance with the scale adopted by the :Board; temporary injuries were weighted according to the actual number of calendar days during which the employee was incapacitated as a result of the injury."

Nov 1, 1926

By Arthur L. Murray

"Oil-shale camps are peculiarly favored, in that before they are establishes it can be ascertained with a degree of certainty, that the life of the project is not limited. Unlike camps at metal mines, where the metal content of a given area is frequently an unknown quantity until after years of development, oil-shale camps should, from the outset, be planned and. built as permanent types of camps. Where this procedure is followed camps will be established which better serve the needs of the industry and the cost of their general care and upkeep will be less.Selection of camp or townsite.The site of the camp or town' whether on company property or not, should be selected with care. It should be separate if possible from the location of the plants of the company so as to be free from noise and fumes and so as to provide a change of environment for employees in going from their work to their homes.The principal features governing the site to be selected are as follows:Drainage. The general contour of the surrounding country should be such that drainage is away from the site. The camp or town should, if practical, be situated on higher ground than that in its immediate vicinity.Soil. The nature of the soil on which the camp or town is located may bear a decided relation to health. A porous, well underdrained top soil of at least four feet in depth insures dryness and facilities the placing of foundations and the laying of water mains and sewer pipes. Such a soil also is an advantage in growing trees, shrubs and grass plots, which are a decided adjunct to making the community attractive.Enviroment. The contiguous territory should afford no unwholesome sur¬roundings such as swamps Or accumulations of stagnant water.General Considerations. The water supply to be provided and the method of disposal of wastes influence to a certain extent the location of the camp or town-site. The means of supplying water, whether by gravity or by pupping, and the disposal of sewage, whether by outfall, system, sewage disposal system through septic tanks, broad irrigation or filter beds, or cesspools will govern the location of the site topographically in relation to source of water and point of disposal of sewage.* This article was prepared as part of the paper ""Use and Supply of Water for the Oil-Shale Industry"" by J. J. Jakowsky, to be published by the Department of Metallurgical Research, University of Utah, in cooperation with the United States Bureau of Mines."

Jul 1, 1921

By Louis C. Britcha

"The Phelps lease in Jasper County, Missouri, was first examined by the Bureau of Mines3/ in December 1943, at the request of Thomas Phelps of Joplin, the lessee. Owing to urgent war requirements for zinc and lead and evidence of favorable geological conditions and past productivity of adjoining properties, it,considered justifiable to explore for extensions of known ore deposits and possible undiscovered ones. In August 1944, funds were allotted for this work, which was started January 5, 1945, under the direction of the author.The provision of facilities and storage space on the property by the lessee during drilling operations is gratefully acknowledged.The Phelps lease is on land belonging to the Rex Mining & Smelting Co. It lies immediately southeast of the city limits of Joplin, Mo. It may be reached by going cast from Joplin on paved 20th street to half a mile beyond Range Line road. Twentieth street is the northern boundary line of the property, which consists of approximately 145 acres and includes the W 1/2, NE1/4, and all of the E ½. NW1/4 except 15 acres along the west side of that quarter section, of sec. 18, T. 27 N., R. 32 W., as shown on figure 1.The property is part of a 1,000-acre tract owned by the Rex Mining & Smelting Co., Paul D. Porter, president, Joplin, Mo. The lease was acquired by Thomas Phelps of Joplin, in 1937. At present the lease is controlled by a recently formed association known as the Eureka Products Co., Charles W. Madison, manager, Kansas City, Mo.Dependable skilled mine labor is scarce in the district at present, but there seems to be enough transient mine labor for small operations. The prevailing wages of the district run from 55 cents to 95 cents per hour for various types of mine labor.Living accommodations and markets to supply all domestic requirements are available in Joplin.In its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the and that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director."

Jul 1, 1946

By R. T. Stull, L. E. Geyer

"Previous Work:As outlined in previous papers* ond clays for graphite crucibles have been tested at the plants of the Detroit Lubricator Co., and the Detroit Copper and Brass Rolling Mills, Detroit, Mich.These tests indicated that there were two American clays (Missouri pot clay and Illinois kaolin) that tested better than the Klingenberg (German) clay. Dorset (English) ball clay was tenth in the list.Making the Crucibles:After it had been determined that American clays can be used successfully in graphite crucible manufacture and service, the next step in the investigation was to determine the value of American graphites as compared to the foreign, These final tests were carried out at the plant of the Detroit Lubricator Co., through the courtesy of Mr. G. B. Duffield. The crucibles, as previously. were made at the plant of the Vesuvius Crucible Co., Swissvale, Penna., from a formula compiled by the Bureau of Mines and under the supervision of Bureau engineers.The graphites to be tested were given an initial to indicate their source. The number of crucibles made and shipped are set forth in Table 1."

Nov 1, 1923

Reduce longwall intake contamination by controlling respirable dust generated by the stage loader. Approach Install a water-powered scrubber on the stage loader immediately outby the crusher. Dusty air from the crusher is drawn through the scrubber and a clean air discharge is delivered into the primary face airflow. How It Works The contamination of intake air is a significant dust control problem often overlooked on many longwall faces. This dust source contributes to the full shift dust exposure of all face personnel, and thus can significantly affect compliance with Federal regulations. Several sources contribute to contamination; however, dust generated by the stage loader crusher is the single largest source. The breaking action of the crusher generates a tremendous quantity of dust, which mixes with the primary ventilation airstream and is carried down the entire length of the longwall face. The installation of a water-powered scrubber (see diagram) has proven effective in controlling crusher-generated dust. The scrubber is mounted immediately outby the crusher. A duct is placed over the scrubber intake and attached to a flanged opening over the crusher discharge. In

Jan 1, 1982

Develop a reliable, portable device for non-destructively testing the support integrity of a friction rock support (commonly referred to as a Split Set ). Approach The friction rock support, used to support mine roof and ribs, is a slotted tube driven into a drilled hole of smaller diameter. Upon installation, the tube is compressed radially. The amount of compression is a function of the hole diameter, the strength of the host rock, and the properties of the split set itself. A simple lightweight self-contained device was developed to determine the pull-out resistance of the friction rock supports in-situ, based on measurements of the tube's deformation. The tester measures the com-pressed internal volume of the slotted tube, which has been found to provide an estimate of the support's resistance to pull out. How It Works The tester consists of a pump and expander sections. The expander sections are made from an elastomer membrane which is stretched over two cores, each one inch in diameter and twelve inches long. The expanders are connected by a flexible coupler so that they can fit any alignment of the support.

Jan 1, 1984

By Henry E. Perlee

In a Bureau of Mines study two-dimensional mathematical equations were solved that describe the transient thermal response of a rock dust particle in a cloud of similar particles in a gas flame's preheat zone subject to a radiant field from the approaching flame. The description includes both radiant energy absorbed and emitted by the particle and thermal conduction inside the particle and into the surrounding gas environment moving relative to the particle. Two situations were studied; in one the radiant energy incident on the particle is converted to thermal energy at the particle surface, and in the other the radiant energy is converted to thermal energy uniformly over the volume of the particle. The result of the study showed that for a 10-µm-radius particle, a 200-mg 1-1 loading density, and a flame approach velocity of 30 m sec-1, the particle temperature rise was twice that previously calculated by Singer and Cook based on the model of Essenhigh and Csaba. It was further established that under the conditions examined a rock dust particle temperature never increases more than about 200 K before crossing the flame front.

Jan 1, 1976

By V. R. Spironello

Operating variables affecting the efficiency of the basic oxygen furnace (BOF) and the level of contaminating elements in the steel product were investigated by the Bureau of Mines. Steel was made in a 400-lb-capacity BOF designed to rotate on its vertical axis to increase the area of hot metal surface subject to oxygen attack. Hot metal for the BOF was made by melting pig iron and scrap in an 18-inch (ID) cupola. The variables were BOF speed of rotation, rate of oxygen flow, number of jets and angle at which they were machined into the oxygen-lance tip, temperature of hot metal, reactivity of lime, and temperature of scrap for the BOF charge. Experiments were arranged according to a two-level fractional-factorial design. The effects of the seven variables were evaluated for 13 responses. The greatest ingot yield occurred while using the larger angle lance tip and jets. The most carbon burned per unit volume of oxygen resulted from rotating the BOF and using the smaller angle lance tip. The largest sulfur transfer to the slag occurred at the higher hot metal temperature levels and higher rate of oxygen flow.

Jan 1, 1970

By John C. Feeley

The methods used and the funds available for the development and oper- ation of shall mines and the reopening of small abandoned mines frequently present problems that tax the ingenuity and resourcefulness of the mining engineer far beyond that required in the mass production from large deposits. The objective of this paper is to describe in considerable detail the means whereby engineers have solved local problems in reopening an abandoned mine at which equipment, facilities, and funds were limited... The Etowah Coal & Iron Co. Gadsden red-iron-ore mine at Gadsden, Ala., 18 of interest in this category since it is the only independent red-ore mine under active development in the State. All other red-ore mines in Alabama are owned or controlled by the large iron or steel companies. The The mine, located on the southwest end of Shinbone Ridge in the outskirts of Gadsden lies in an ares once productive. but now idle, for many years. ore is relatively highgrade compared with that in the Birmingham area, but the bed is thin and somewhat lenticular. The presence of a large blast furnace at Alabama City, 3 miles from Gadsden, and the growing scarcity of red-iron ore supplies for it offered inducements for reopening the mine in 1946. Up to the time this circular was prepared (1947) only a small quantity of ore (about 1,500 tons) has been produced and shipped to the furnace. A force of 14 men was employed in sinking the main slope and developing a third "lift" (a local term for level) 100 feet below the old mine workings.

May 1, 1949

By Howard E. Rollman

South Central United States, an area including Arkansas, Kansas, Louisiana, Mississippi, Missouri, Oklahoma, and Texas, is a net exporter of refractories. Nearly $45 million of these materials was shipped in 1954 from plants in the area, compared with area consumption of $18.5 million. About 88 percent of all refractories production is concentrated in Missouri. The prevalent consumption pattern, however, is one of localized shortages. For example, although Texas uses more than half of the refractories consumed in the South Central United States, production of refractories in Texas is relatively small. Also, the apparent self-sufficiency of the area is in terms of value produced rather than in terms of products consumed. Nearly all of the $6,425,000 nonclay refractories consumed in the area were shipped from other States. Local resources possibly could be developed for making refractories to serve markets that currently are being supplied from outside the area. Since other industries are growing rapidly in the area, the market for refractories is expected to continue to grow--more rapidly than the national market. The Missouri refractories industry is economically important nationally. Nearly one-fourth of the clay refractories produced in the United States are made in Missouri. Moreover, Missouri produces most of the higher grade clay refractories, about 62 percent of the high-alumina refractories, and 85 percent of the superduty refractories. The competitive position of the Missouri refractories industry is strong. The national market for clay refractories and the market in the South Central United States are expected to continue to grow. The ratio of net income to the value of refractories shipped in Missouri is larger than the national average.

Jan 1, 1960

By T. E. Gray

This report describes the preparation characteristics of the significant coalbeds in Harrison County, W. Va. It is one in a series of Federal Bureau of Mines reports planned to determine coals suitable for the production of metallurgical coke, either as mined or after beneficiation. Over 6.5 million tons of coal was produced in Harrison County, W. Va., in 1958, of which over 3.7 million tons was cleaned mechanically in seven preparation plants. All of the coal cleaned was from the Pittsburgh bed. It has been estimated that more than 1,816 million tons of coal remains in the county in beds 12 inches or more thick. The Pittsburgh and Redstone beds were selected by the Bureau for a study based on current production rates and estimated minable reserves. Sample locations were selected following a study of the literature, conferences with mining engineers and mining company officials in the field, and examination of the available sites. Six samples were collected from the Pittsburgh bed, and three samples came from the Redstone bed, Float-and-sink tests of the samples collected from the Pittsburgh and Redstone beds showed that neither coal could be upgraded to a metallurgical fuel under the standards set up for this study, even after intensive preparation. Finer crushing of the samples moderately increased the yields and slightly reduced both the ash and the sulfur contents in the 1.30-specific-gravity float fractions. Finer crushing slightly decreased the yields in the 1.58-specific-gravity float fractions, whereas it reduced the sulfur content 0.11 percent for the Redstone sample and 0.46 for the Pittsburgh sample.

Jan 1, 1961

By R. H. Storch

"A preliminary examination of the Bi-Metallic molybdenum prospect was made in October 1944, as a result of which it was recommended that a trench exploration project be undertaken on the property. This report presents the information obtained from project work done during June 1945.In its program of exploration of mineral deposits, the Bureau of Lanes has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to the national security and. economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director.With respect to this report, special acknowledgment is due S. H. Lorain, chief, Albany Division, Mining Branch, for aid in preparing the report.The property is situated in the NW1/4, sec. 26, T. 39 N., R. 29 E. about 21 miles northeast of Tonasket. Tonasket (population 643), the nearest town, is a way point on a branch line of the Great Northern Railway. The prospect is reached by a good gravel road through Havillah to Vincent's ranch, about 3 miles northeast of Havillah. From the ranch, an abandoned dirt road extends to the portal of the Moly alit, about 1 mile distant. The mine road could be kept open without difficulty if properly graded and surfaced."

Aug 1, 1946

This surveillance report summarizes data on work-related fatal and nonfatal injuries, illnesses, and hazardous exposures in the mining industry for the 10-year period 1986-1995. The term "surveillance," as used in public health, may be new to many readers of this report. With regard to occupational safety and health, the goal of surveillance is to describe the occurrence of work-related injuries, illnesses, and known hazardous exposures; to identify new hazards that may occur due to the introduction of new technology or other factors; and to assess the effects of preventive measures designed to improve worker safety and health. Surveillance provides an overall picture, which can be used to focus resources on areas most in need of prevention programs or further research. Surveillance generally requires the use of multiple sources of data, all of which have their own strengths and limitations. Surveillance in the U. S. mining industry is complicated by the fact that U.S. national data systems that provide information on mining are based on two different definitions of the mining industry. One is established by the Mine Safety and Health Administration (MSHA), the other by the Standard Industrial Classification (SIC) System [Office of Management and Budget 1987] and the 1980 U. S. Bureau of the Census (BOC) Classification System [U.S. Bureau of the Census 1982]. The mining industry as defined by MSHA is based on the regulatory jurisdiction of that agency. Reporting requirements for injuries, illnesses, and workplace exposures are stipulated under the Federal Coal Mine Health and Safety Act of 1969 and the Federal Mine Safety and Health Amendments Act of 1977. Of note is that the oil and gas extraction industry falls outside of MSHA jurisdiction. The Occupational Safety and Health Administration (OSHA) was charged with enforcement in the oil and gas industry under the Occupational Safety and Health Act of 1970. Under the SIC, the definition of mining covers the extraction of naturally occurring minerals, including liquids (petroleum), gases (natural gas) and solids (coal, metal, and nonmetallic minerals). Exploration and development of mineral properties are also included in the SIC definition of the mining industry. The SIC was developed by the Office of Management and Budget for use in classifying establishments based on the type of economic activity in which they are engaged and serves as the industry classification standard for all establishment based Federal economic statistics. This classification is important for occupational safety and health surveillance because it also serves as the industry classification system for all data on work-related injuries and illnesses collected by the U.S. Bureau of Labor Statistics (BLS). The U.S. Bureau of the Census uses an industry coding scheme similar to that used by the SIC. For the mining industry, the categorization is identical in both systems. Death certificate data made available by the National Center for Health Statistics (NCHS) are categorized under this system. Death certificate data are particularly important for surveillance of mortality from work-related illnesses. Key differences between the SIC/BOC categorization system and the MSHA system can be summarized as follows: • MSHA excludes the oil and gas industry, which is classified as part of the mining industry under SIC/BOC. • MSHA excludes work that is done off of mine property; work off of mine property is included under SIC/BOC if it is performed by an establishment falling into one of the SIC/BOC mining industry codes. • MSHA includes mine-associated mills and processing plants; these are classified under the manufacturing industry, rather than mining, according to the SIC/BOC coding structure. Since the data collected by MSHA and the data collected by BLS and NCHS using the SIC/BOC classification system are both important sources of information on the mining industry and in many cases serve different purposes, data from both systems are presented in this report. In general, data using the SIC/BOC system are comparable across U.S. industries and should be used when comparing mining to other U.S. industries. Much of the data in this report are presented in the form of frequencies or rates. A frequency provides only a count of the number of cases without providing any information about the risk of occurrence. Rates provide an estimate of the risk of injury or illness. The reader is cautioned, however, that rates based on small numbers can be unstable; thus, any inferences should be drawn with care. In this report, no rates are presented for groups in which there were fewer than three cases. The incidence of most injury and illness conditions differs by age, sex, and race. For this reason, data in many surveillance reports are adjusted for these demographic factors. It was not possible to do this for most of the rates in this report because information on demographics was not available. With the exception of the proportionate mortality ratios (PMRs), all data presented are unadjusted. A detailed account of the sources of data is in appendix A. The methods used in data selection and analysis are described in appendix B.

Jan 5, 2000

By E. K. Kleespies

The Bureau of Mines determined the kinetics of the reaction of titanium-iron alloys with titanium trichloride dissolved in sodium chloride to provide a basis for understanding the reactions occurring in metallurgical processes involving reduction of the metal halides or alloy refining in fused salts. The rate of the heterogeneous reaction was determined between titanium-iron alloys and titanium trichloride to elucidate the effects of alloy composition on the rate. Measurements were made in an inert atmosphere with a high-temperature thermobalance using high-purity reactants. The rates of the reactions were about 1 x 10-5 g Ti/cm2-sec, and the reaction was phase-boundary controlled. Titanium alloys of the body-centered cubic beta structure reacted faster than those with the hexagonal close-packed alpha structure. The inter-metallic compound, TiFe, reacted very slowly, whereas TiFe2 was inert. Alloys containing above 89 atomic percent iron gained weight by reacting with titanium species in the salt solution and depositing titanium in the alloy. The effect of TiCl3 concentration on the reaction rate was determined from 2 to 12 weight-percent TiC13 and at various alloy compositions. At high iron contents, above 50 atomic percent, the TiC13 concentration effect was small. At lower iron contents, the TiC13 concentration effect was greater for beta-crystalline alloys than for alpha-crystalline alloys. The temperature dependence of the reaction between titanium alloy containing 8.7 atomic percent iron and titanium trichloride was measured over the temperature range 1,062° to 1,220° K, and the energy of activation was 7.7 kilocalories for the reaction.

Jan 1, 1967

SCOPE AND APPLICATION The rules cover the installation and use of electrical equipment in coal mines.- For generating stations, substations, lines, and equip¬ment aboveground, reference is made to existing rules covering such locations, viz, the National Electrical Code and the National Electrical Safety Code and any existing State or municipal regulations. The purpose of the rules is to set forth methods for safe electrical installation. In preparing the rules five basic measures for safe¬guarding the use of electricity in mines have been followed, viz 1. Remove the contributory causes of accidents or danger. 2. Remove from the vicinity of electrical apparatus all elements susceptible to the influence of electricity. 3. Keep the electric current where it belongs, if possible; if not, limit the area of its activity by protective devices. 4. Use a. large factor of safety in the selection, installation, and in¬ spection of equipment. 5. Have full control of the operation of electrically driven machines. Each rule that is given is proposed as necessary or helpful to the accomplishment of one or more of these measures. DEFINITIONS OF TERMS USED Alive.-See definition of " live." Approved.-The term " approved " means accepted as suitable by a competent committee, board, or organization designated by those adopting the rules. Authorized person.-The term " authorized person " means a per¬son appointed or permitted by the official designated by the State mining laws as the one in charge of the operation of the mine to carry out certain duties incident to the generation, transformation, and distribution or use of electric energy in the mine, such person be-

Jan 1, 1926

By Walter L. Fisher

The public interest in the Alaskan situation is such that, with the consent of the President, I have concluded, at the request of the American Mining Congress, to make at this time a candid, if somewhat informal, expression of the views I have formed as Secretary of the Interior, under whose official supervision much of the administration of the Territory is now placed. Pressure of other matters imperatively requiring attention has prevented their presentation in as precise and comprehensive a form as I had hoped. The absence of the President from Washington has also prevented the submission to him of what I have prepared. I wish to say, however, that no one is more earnest than he in the desire to see a policy of prompt and wise development inaugurated in Alaska, and that the general policy contained in this address has been discussed with him, meets his approval, and will have his support. I have recently returned from an altogether too brief but nevertheless a most interesting and profitable visit to those portions of Alaska that are more immediately involved in the questions now under public consideration. Favored by extraordinary weather and the cooperation of steamship and railroad lines and the assistance of all of the governmental agencies, including the Revenue-Cutter Service, I visited every port in Alaska that seems likely in the near future to become an important entrance to the country. I examined all of the harbor and town sites which for this purpose have attracted any considerable public attention. I traversed the entire length of each of the three railroads that have been constructed in the Terri.tory and made a short trip from White Horse down the upper Yukon. Both before and during the journey I examined a mass of books, records,' and papers relating to the country and its resources. I had conferences with official committees representing the principal communities I visited and with numerous individuals, residents both of the coast and of the interi.or, and conferred with engineers, miners, prospectors, railroad officials, business and professional men.

Jan 1, 1911