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By H. H. Stoek

It would permit coal mines to operate continuously instead of intermittently . Intermittent operation increases the cost per ton for mining , and makes the yearly return to labor low . These conditions contribute to serious instability and unrest in one of the fundamental industries of the country and this can be changed only by coal buyers doing their part to insure steady work . The railroads are now required to transport the maximum amount of coal during the winter months when traffic is most interfered with by bad weather and when the maximum amount of coal is used by the railroads to handle other coal . The railroads now use nearly 30 per cent of the total output of coal . About one- third of their freight traffic is hauling coal , so that economy of fuel used by the railroads will produce a considerable gross saving .

Apr 1, 1920

By R. B. Ladoo

"Present Situation:At the beginning of 1920 a general feeling of optimism was noted in many talc-producing districts. The industry seems to have recovered from the temporary depression of the first half of 1919 and many mills are running at capacity production with their entire output for 1920 contracted for. The imports of talc for 1919 were only slightly larger than in 1918 by weight and probably no more by value. Thus foreign competition has not begun to be seriously felt. Several new companies in this country have been organized, some to operate new deposits and others to continue the work done by others.An interesting phase of the present situation is the possibility of increased use of talc in paint. There is a shortage of barium sulfate used as a paint filler. Since, for some uses, talc is considered second only to BaSo4 as a filler for paint, it is possible that part of the shortage could be relieved by an increased use of talc.A series of physical tests upon all pigment materials used in the manufacture of paints is being conducted for the Paint Manufacturers Association of the United States. It is important that all types of talc be represented in these tests. Producers of finely ground talc, 200 mesh and finer, are urged to submit samples of at least two pounds each of these grades that are available to paint makers with trade name and quality data, to the Institute of Industrial Research, 19th & B Streets, N. W., Washington, D. C., where the tests are being conducted."

Jan 1, 1920

By Robert J. Anderson

"Introductory Statement.In founding any kind of castings, even with the best practice, scrap castings are produced because of rejections for certain defects. Casting los¬ses are a serious source of financial loss in iron and steel foundry practice as well as, in brass and bronze, but they are particularly serious in aluminum foundry work because of the high value of aluminum. The indications are that in many aluminum foundries in the United States, the casting losses are at times high, and in some plants they are entirely too high when compared with average practice. Of course, defective castings have a residual value for remelting, but if much machine work has been done on a casting before it is scraped, the labor costs alone may exceed the value of the metal and even that of the rough casting.In a foundry, the monetary losses incurred through the production of waster castings can be ascertained from calculations based upon adequate scrap-loss reports. Such reports, when properly kept and interpreted are a valuable aid in finding foundry costs, but they are primarily useful in diagnosing the causes for casting losses. Many aluminum foundries in the United States do not keep adequate records of strap losses; as a result the causes for defective castings can not be traced, nor preventative measures adopted. However, some of the large aluminum foundries keep excellent records, and it has been found that these involve little extra expense for clerical work. If a foundry man will study his daily production of defective and waster castings, he will be able to trace the causes or losses and then make such corrections in his plant practice as will effect a considerable reduction in these losses -- as much as 50.0 per tent in some foundries. If all the present casting losses of the United States could be reduced 50.0 per cent, by eliminating only the readily preventable defectives, a saving of several million dollars would accrue. In the aluminum-foundry industry alone, the saving would amount to about $600,000."

Apr 1, 1920

By Thomas Varley

"Concentration, ore-dressing, or the dressing of minerals are common terms used in metallurgy and indicate processes of separating valuable minerals from worthless gangue. It is understood, of course, that the products from such processes, being separated from the various minerals and gangue, are ready for commercial sale or for further treatment by smelters and refineries.Gravity concentration takes advantage of the difference in specific gravity of the various constituent minerals and gangue of waste material in the ore. The two most common forms of concentration by this means are jigging and table concentration. Jigs usually are used in the separation of relatively coarse material and the tables for the finer material, the line of division in general being about 20 mesh.There are mar factors to be considered .before a decision can be made as to what method would be best adapted to the successful treatment of an ore and only by careful experiments can this be determined. Among the important factors to be considered are. The nature of the minerals present, their physical and chemical relations to the gangue material, and the gangue material itself. Perhaps the most important is the number of minerals present and their relation to each other.Metals exist in ores in three principal forms -- sulphides, oxides or carbonates, and native. Concentration by gravity methods is in general best suited to sulphide ores, although in some places considerable success has, been obtained in the concentration of oxide ores by gravity methods."

Apr 1, 1920

By T. T. Read

"Education is the one thing which is unanimously regarded as valuable. The growing complexity of modern life, with its intricate organization, the manifold kinds of mechanical equipment that are used, and the constantly growing, necessity for the speedy and accurate interchange of information and ideas, make education an asset that constantly increases in value. The number of things that may profitably be known has grown so large that the field of education has been divided, and attention is often directed to only those things that are most immediately valuable. Modern educational facilities are often directed to what may be called corrective, work; the, providing of people with information that they teed in the conduct of their daily lives, but which for various reasons they have not previously had facilities for acquiring. The value of special education in the industrial world has been so thoroughly demonstrated that far-seeing managers of mining enterprises are always interested in the educational facilities existing in the community where their work is carried on.The educational facilities of a modern community may be classified in several ways. They may be divided into;1. Facilities for general education, for the purpose of increasing the whole field of knowledge of the student.2. Facilities for special education, which are intended to remedy a specific defect, or to give proficiency in some special field. This may be divided as follows;a. Training for work, intended to fit an employee to adequately perform the task assigned to him, this ranges from brief instruction by a foreman or fellow-worker up to definite training courses in which the employee dose nothing but study for a period of several weeks or months, being paid during this period a wage that may range from a nominal amount up to practically full time salary. The student's educational preparation may already be fairly advanced. Some of the manufacturers of electric machinery maintain, a school similar to that just described for graduates of engineering colleges. In other cases the only pre-requisite may be a common school education, as in the schools for operators, maintained by the telephone companies."

Apr 1, 1920

By Arthur L. Murray

"During recent months much criticism as to the efficiency of mine labor has been heard from various, sections of the country. No doubt much of this criticism has been well founded. The present lack of efficiency and of stability is due primarily to a spirit of restlessness and partial irresponsibility engendered during the transition from war conditions to peace time conditions. This spirit or unrest not only among the laboring classes but in every branch of the human family following a period of intense nervous tension in a nation appears to be a natural sequence of war and beyond the control of man. This condition will gradually disappear, and the majority of our people will again assume their natural order of living, but labor will for a considerable period be sensitive to these influences, whether they be exerted for good or for evil. Employers of labor should take cognizance of this fact and bend every effort towards the development of measures that promote efficiency and permanence of the working force.Labor efficiency depends upon many and varied factors. Some of these factors as applied to mine labor are briefly enumerated in the following paragraph:Selection and Placement of Manpower:In the selection of men the two main considerations are physical ability and adaptability. The laws of mechanics should be applied in the selection of men as in the selection of machinery. If a machine is required for a certain class of work, the type of machine known to be mechanically fit for such work is selected. Likewise, men should be selected with regard to their physical and temperamental fitness for the kind of work expected of them."

Apr 1, 1920

By J. H. Wiggins

The evaporation of crude oil without doubt causes one of the largest single losses to which the oil is subjected after it is taken from the ground. The few days during which crude oil is stored on the lease before being taken by the pipe line, causes an aggregate loss per year from evaporation estimated at 122,100,000 gallons of gasoline in the Mid-Continent field alone. This has a value, at 22 cents per gallon, of $26,880,000 and represents about 3 per cent of the total gasoline produced in the United States from all fields and all sources. The following table shows this in more detail:

May 1, 1920

By R. E. Collom

The spontaneous explosion of charges of nitroglycerin placed in deep wells situated in parts of the Ranger and Caddo fields of North Texas has aroused considerable inquiry among operators end others as to the probable agency, or combination of conditions, which causes the explosion.The method now followed, under certain physical conditions of a well, of setting a charge of nitroglycerin and allowing it to explode spontaneously was discovered locally by accident. In certain deep wells where formations, overlying productive strata, cave upon withdrawal of casing, it has been the practice to fire the shot electrically. In some of these operations the electric wires are broken or the firing system is otherwise deranged by pulling casing or the caving of hole prior to the time for firing. Sucn accidents make it necessary for the driller carefully to clean cavings out of the hole to a depth close to the top of the charge, after which in the normal practice, an attempt is made to fire the charge by dropping a ""jack-squib"", fitted with a fuse and detonator, down the well. Mr. R. L, Fowler, production manager for the Pierce Oil Corporation, reports that a delayed shot was thus successfully tired through four feet of caved material lying on top of the nitroglycerin shells.When a shot destined to be fired electrically fails, because of the above mentioned accidental conditions to the electric firing system, much time is required for the driller to run casing into the hole and clean out caved material. It was during the time of such uncompleted operations that the spontaneous explosions first noted took place. Having noted these spontaneous explosions the well shooters now intentionally place a charge in deep holes, which because of probable caves would otherwise have to be tired electrically, and wait for the charge to go off. No detonators are placed with the charge.

May 1, 1920

By Raymond B. Ladoo

[Inquiries are frequently received by the Bureau of Minas relative to occurrence, mining, treatment and utilization of the natural hydrocarbons' such as gilsonite, elaterate, wurtzilite, grahamite, and ozokerite although have been known and used for many years, they are not yet well understood and the amount of recent literature dealing with them as comparatively small. This paper is intended merely to summarize the present knowledge The natural hydrocarbons included in this series are gilsonite, elaterite, wurtzilite, glance pitch, manjak, grahamite, albertite, arid ozokerite and many other minor varieties. With the exception of ozokerite and the other mineral waxes, then all more or less resemble asphalt in that they are dark brown or black bituminous substances of organic origin, generally with a resinous luster. Ozokerite usually light an color with a waxey luster, is closely allied to the others of the series, but is usually considered separately, Unfortunately authorities differ as to nomenclature so that determinations of physical and chemical properties from different sources may riot be readily compared. Abraham Herbert, Asphalts and Allied Substances, 1918, 606 pp. has made one of the most detailed studies of these subjects in recent years, and his classification is used in the main. The following definitions are given by him]

Jan 1, 1920

By F. D. Osgood, A. C. Fieldner, W. A. Selvig

In connection with investigations being conducted by the Bureau of Mines regarding pulmonary disease which is prevalent among metal miners in certain districts , a large number of rock- dust samples have been collected , and have been examined in the Bureau's laboratories . The earlier work has been described in Bureau of Mines Technical Paper 105 , " Pulmonary disease among miners in the Joplin district , Missouri , and its relation to rock dust in mines " by A. J. Lanza and Edwin Higgins , 1915 , and in Bureau of Mines Bulletin 132 , " Siliceous dust in relation to pulmonary disease among miners in the Joplin district , Missouri , " by Edwin Higgins , A.J. Lanza , F.B.Laney , and Geo . S. Rice , 1919. The methods of collecting and examining dust samples have been greatly improved during the investigation , much valuable information having been made available by similar investigations conducted by the Miners ! Phthisis Prevention Committee , Union of South Africa . The latter are described in the " General report of the Miners ' Phthisis Prevention Committee , Johannesburg, Union of South Africa , 1916 " , and " Final report of the Miners ' Phthisis Prevention Committee , Johannesburg, Union of South Africa , 1919. " The investigations by the Bureau of Mines and the South African committee show that by prolonged inhalation of air containing minute particles of sharp and insoluble rock dust , the lungs retain sufficient dust particles to cause decided injury to the lung tissue , the injured lung becoming very susceptible to the development of tuberculosis .

May 1, 1920

By L. C. IlsLey, E. J. Gleim

It is the firm belief of the Bureau's engineers that the introduction of electrical mining machines has done much to increase safety in mining as a whole . There can be no doubt but that the substitution of machine mining together with permissible powder for the method of " shooting from the solid " has been the means of saving the lives of many shot- firers . Machine mining also leaves the roof in a better condition as lighter charges of powder are required to bring down the coal . Thus the danger from falls of roof are lessened . It is recognized that every effort should be made to prevent all accidents due to the use of electrical machinery but it is felt that any action tending to limit the use of such machinery would be a backward rather than a forward step in the safety measures laid out to decrease the hazards in coal mining .

May 1, 1920

By A. B. Hooker, Iilsley. L. C.

"Flame safety lamps have been used for about one hundred years in coal mines where a dangerous accumulation of explosive mine gas (methane) might occur and thus render the use of ordinary unprotected flame lamps dangerous. Flame safety lamps are not only used for illumination, but also for detecting the presence of dangerous percentages of methane mixed in the air of the mine.The safety of the lamp depends chiefly upon the cooling qualities ofThe safety of the lamp depends chiefly upon the cooling qualities of the wire gauze used to permit free circulation of the air through the lamp. If one enters a part of the mine where methane is present in the air, the methane enters the lamp and coming in contact with the wick flame is ignited and continues to burn within the gauze without igniting the methane surrounding the lamp. If the air within the mine is traveling at a velocity of several hundred feet per minute the burning gases may be driven through the gauze by the air current. If the gauzes are properly designed and of the proper material, these burning gases will be so cooled as they pass through the gauze that they will not cause an ignition of the gas surrounding the lamp. In order to test the effectiveness of a given safety lamp, tests are made in moving explosive mixtures of gas and air arranged to simulate mine conditions.The Bureau of Mines investigated many features relative to the safety of flame lamps and in 1915 established an official schedule known as Schedule 7 whereby flame lamps having certain prescribed qualifications would be approved as permissible for use in gaseous mines."

May 1, 1920

By W. C. Phalan

"Prewar Conditions:Metallic magnesium may be considered a war metal, but a war metal with a future, so far as the industry in the United States is concerned. Its production in the United States prior to 1915, on a commercial scale, was negligible, but imports prior to that year may be taken as a gaze of the demand for the metal. Unfortunately, magnesium was not listed separately by the Department of Commerce prior to the war, among the importations, but was included with other metals, as follows: ""Barium, calcium, magnesium, sodium, and potassium, and alloys of which said metals are the component materials of chief value."" However, the imports of metals enumerated other than magnesium were probably small, so that the importations under the above caption may be considered chiefly metallic magnesium in one form or another and, therefore, is an approximate gage of the demand for the metal in the United States. These imports were as follows:These figures are so close that they give a good idea of the figures for the respective calendar years.Of this prewar use, it has been estimated that about 85 per cent was used annually and in approximately equal quantities in the production of (1) flash-light powder, (2) fire works, (3) aluminum casting work, and (4) nickel and nickel-copper alleys, such as monel metal, etc. The re¬maining 15 per cent was employed for general uses, such as deoxiding brass and other copper alloys in foundry work, and to a small extent in laboratory and research work."

May 1, 1920

By Oliver Bowles, J. E. Crawshow

A line of cordeau detonating fuse was placed in hole No. 2, no electric detonators being used in the hole. After 12 or 13 cases of 40 per cent nitro starch powder had been poured into the hole in loose form, it was found that a space of only 17 ft. remained for stemming. It was decided that space for an additional case of powder might be obtained by tamping the charge. The tamping was done with a heavy plunger, about 3 or 3 inches in diameter and 10 inches long, made of lead with an iron core with an iron eye in the top to which a 3/4 inch rope was attached, and weighing between 30 and 40 pounds. This weight was intended for use in sinking explosive in wet holes, and not for tamping. It is estimated that the tamping had continued at least 10 The quarry superintendent had gone a considerable distance for a box of powder, returned, and reached a point about 10 feet from the hole, minutes.

May 1, 1920

By Raymond B. Ladoo

The uses of talc are many but are not, in general well known or fully developed within the last decade several companies have realized the possibilities of greatly increased use and have intelligently proceeded to develop some of the fields which seemed most promising. This has had a tendency to lift talc from the obscurity in which it had existed for years, but the work is only started and much remains to be done. Considerably more attention has been paid to the technology and utilization of talc in Germany and Austria than in this country, despite the fact that the United States produces 65 of the world's talc and Germany and Austria combined but 5.4%. In the "Bericht,uber die tatigkeit des verbends der talcum-interessenten in Oesterreich-Ungarn" (Proceedings of the Austro-Hungarian Talc Association), for the years 1912 and 1913, many notes upon new uses appeared, together with suggestions as to further development of old uses. Aside from a few notes on the use of tar in paper, little has been published in the English language upon this subject. By recent action of the Talc and Soapstone Producers Association (U.S.A.) funds for research into the properties and uses of talc have been made Available and it is hoped that markets will be materially broadened a a result of this work.

May 1, 1920

By G. St John Perrott

"The United States Bureau of Mines is cooperating with the State of Utah and the City of Salt Lake in an investigation of methods of abating the smoke nuisance in Salt Lake City. In the course of this work samples of the atmosphere have been collected and analyzed in an attempt to determine the part played by sulphur dioxide or smelter gases in polluting the air at Salt Lake City.A fairly wide-spread opinion exists in Salt Lake City that the smelters contribute appreciably to the smoke nuisance. The gases discharged from the smelter stacks are believed (1) to float over the city in a heavy blanket which prevents the smoke from rising, and (2) to unite with the water vapor in the air to form corrosive fogs injurious to health and property.The first of these theories seems untenable. If the gas did not mix with air it would sink, owing to its heavier specific gravity, and form a blanket an the earth. Actually, the gas diffuses rapidly in air and any part reaching Salt Take must he thoroughly diluted. Perhaps sulphur dioxide in sufficient concentration might aid in fog formation. The more obvious nuisance, however, would be the injury to health and vegetation.The Garfield smelter is 16 miles west of the city, The Murray smelter 8 miles south, and the Midvale smelter 12 miles south. Under normal operating conditions, a relatively small amount of solid matter is discharged from these stacks. The toxic gaseous constituent of the discharge is sulphur dioxide, it is being discharged from the smelters the year round. If they are a factor in the city's smoke problem, the concentration of this gas in the air of the city should be appreciable and should increase toward the smelters, the con centration being highest with a south or a west wind."

May 1, 1920

By J. W. Thompson

"The ordinance of March 27, 1919, contains provisions relative to the exploration for, Ind the exploitations of bauxite in the Colony of Surinam in Dutch Guiana.Permission to explore is limited to: Netherlanders; inhabitants of the Netherlands; inhabitants of Surinam; companies established in Netherlands, and companies established in Surinam.Holders of concessions for the exploitation of bauxite are limited to companies established in the Netherlands, or in Surinam, and these must reside in the Colony or must be represented the constantly.A permission or concession lapses: (a) when the holder ceases to have the required qualifications; (b) on the death of the holder where the assigns fail within one year to prove the required qualifications.Any dispute concerning the required qualifications must be decided by the Judge in the manner to be regulated by colonial ordinance.The Governor may, after consultation with the Privy-Council reserve tracts of land for the exploration and exploitation of Bauxite, either for the Government directly, or for concession under special provisions. These provisions shall be fixed by virtue of the colonial ordinances.Application for permission to explore shall be made in accordance with existing laws. Simultaneous applications, those made on the same day, must be decided by drawing lots; but an application for the concession for exploitation has preference ovor that for permission for exploration. On notice of objection to the drawing of lots, the Governor may in his discretion, declare the drawing null and void and order a re-drawing."

May 1, 1920

By Marting J. Gavin

The twentieth century has often been spoken of as the age of petroleum, and from many viewpoints it can be justly considered so. Certainly the petroleum industry is one of enormous importance to this country, industrially, financially, and economically. The United States, however, at present producing over 60 per cent of the world's total output of petroleum, is not producing petroleum at a sufficient rate to provide for its own domestic, consumption. For several years this country has been importing increasing quantities of crude and partly refined oils from Mexico, and has been drawing heavily on domestic stocks of petroleum. Production in the United States is increasing, but it is not increasing at the same average rate as domestic consumption, nor is it probable that in the future domestic production will increase sufficiently to satisfy the demands of domestic consumption, but on the contrary, in the opinion of those best qualified to know, the peak in the curve of domestic production of crude petroleum will be reached in a comparatively few years, whereas the consumption of petroleum and its product will increase at a continually growing rate. This country, then, must turn, and as the increasing imports from Mexico indicate, is turning to other sources than the crude petroleum, produced in this country to make up the deficit between domestic production and domestic consumption of petroleum and its products,

Jun 1, 1920

By D. Harrington

The desirability of efficient control of air currents, and the necessity of supplying metal-mine workers with better and safer working conditions, has created an active interest in metal-mine ventilation, especially in recent years. This paper discusses the subject both with regard to efficiency and economy, as well as safety and health. It is based on personal observations of the writer from over four year's study of metal mines in six States, in which more than 50 mines were visited. Many of these were studied in detail; in all several thousand working places were examined, and readings taken relative to ventilation run into the tens of thousands.Object of ventilating metal mines:Whereas in coal mines ventilation is generally regarded as essential, in many metal mines, especially shallow ones, the operators pay little attention to ventilation, or ignore it altogether. Recent shortage of labor, and numerous accidents to which State compensation laws have directed attention, are causing metal-mine operators to regard ventilation more seriously, especially in deep, large mines.There is, in fact, greater necessity for adequate ventilation of metal mines than of coal mines. The latter require air currents to remove explosive gases and the fumes of explosives, but metal mines, in addition to the need of removing fumes of explosives, and occasionally explosive gases, frequently have need of removing dusts dangerous to health, reduction of high temperatures and high humidity, and removal of inert but unhealthful gases like CO2 and nitrugen. The generally accepted superior healthfulness of coal miners as compared with metal miners, is probably due in large part to the better air circulation in working places of coal mines.

Jun 1, 1920

By C. A. Allen

"The problem of signaling to the hoisting engineer from a moving cage in the shaft has been considered by many mine operators for a number of years. There are several methods in use in different mining districts, and so far as the writer is aware they have been further developed in Utah than in any other state. The latest installations are of interest because they use a very low-voltage circuit for the shaft wires and also because the wiring can be so arranged that the hoist can be stopped from the cage, if so desired.The first installation in Utah was in the shaft of the Centennial-Eureka mine under the management of C. E. Allen. It was placed in operation in the summer of 1899, end has been in continuous and satisfactory operation for 21 years. The arrangement consists or two bare wires down the shaft carrying a current at 60 volts potential, with a device on the cage for making connection between the two wires. This device is simply a short piece of wire which is thoroughly insulated from the cage and is operated by a short lever. Whenever the cage rider wishes to signal the engineer he pulls down the lever, forcing the short wire out against the two bare wires, thus making a circuit which rings the bell in the hoist-room. A similar device was planned in the Grand Central shaft at Mammoth, Utah, but was later abandoned. The cause of failure was reported to be that the shaft was very wet."

Jun 1, 1920