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By H. A. BURK

THE ores of the Tonopah, district are hard, compact and' highly siliceous. They contain from .1 to 2, per cent. of sulfide material, of which argentite is the valuable mineral; occasionally pyrargyrite is found in the richer ore. The sulfide is, chiefly pyrite with small amounts of chalcopyrite,. and sometimes sphalerite. The ore also contains a small amount of gold-about 1 per cent. by weight of the silver present. The major gangue constituent is quartz but frequently considerable rhodonite-called by the miners pink manganese-is present. For primary crushing, jaw and gyratory crushers are used. These crushers are of such capacity that, in most cases, one 8-hr. shift will supply the mill for 24 hr. The Extension Co., at the Victor ore house, passes the ore through a 13 by. 24-in. Blake type McFarland crusher set at 13 in., and at the No. 29 re house, a 14 by 24-in. Blake type Traylor crusher is used. The ore is thus crushed to stamping size in one reduction. The capacity of each crusher is about 40 tons per hr.; the power consumption is 0.6 kw. per ton.

Jan 1, 1921

By John V. Beall

Probably the only hotel in the world with near 100% occupancy at all times is the modern Hotel Indonesia in Djakarta. However, there is little gaiety among the scores of business men who occupy the hotel because they fret as days grow into weeks in seemingly interminable negotiations with government officials. As one man put it, "time is a dimension that they [Indonesians] have never grasped." But the visitors still come in droves to investigate business opportunities in this sprawling nation of tropical islands which is, with 120 million people, the fifth largest nation in the world. Approximately $300 million is being spent each year in Indonesia by foreign companies and governments. Aid grants from the latter are derived about one third from the United States, one third from Japan and the remainder from many nations. Djakarta is a far cry from pleasant colonial Batavia, as the city was called under the Dutch. The orderly colony of prewar days was managed as an agricultural and trading dependency of Holland. The Dutch did little about educating the people. The islands were controlled by the Japanese during World War II and afterwards there was a war for independence--which was attained in 1949. In the ensuing years, President Sukarno devastated the economy by squandering money on a gigantic scale. A Communist-attempted coup in 1965 resulted in a military takeover and the extermination of Communists. The new government under Suharto, which took over all power in March 1966, found itself in a situation where bare survival was the first consideration.

Jan 1, 1970

By J. Q. Ehrgott

INTRODUCTION The U. S. Army Engineer Waterways Experiment Station (WES), under sponsorship of the Defense Atomic Support Agency, has recently developed a unique dynamic high-pressure triaxial testing device (DHT). The device permits acquisition of both axial and lateral deformation data while undisturbed soil and/or rock specimens are subjected to various states of controlled impulsive-type stresses produced by varying both the axial stress and the radial stress rapidly with time. The device is used to develop controlled dynamic pressure pulses within the triaxial chamber fluid on soil or rock test specimens to 3 inches in diameter. Controlled dynamic axial pulse loads are delivered to the specimen by a piston driven by an existing pneumatic ram loader (SECO). The DHT consists of a triaxial cell and a pressure supply and decay system which permits the chamber pressure to be varied with time. Together the DHT and SECO operate in a testing program so as to provide time varying confining pressures and axial loads to test specimens at independently controlled but synchronized programmed rise, hold, and decay times. Rise time is defined as the time from zero load or pressure to peak load or pressure; hold time is the time of constant peak load or pressure; and the decay time is the time from peak load or pressure to zero load or pressure. The maximum dynamic confining pressure attainable is approximately 15,000 psi and the fastest rise and decay times are 3 millisecond (msec) and 20 msec, respectively. This paper presents a description of the DHT, the necessary support equipment, and details of the measurement system. Performance evaluation tests conducted on clay siltstone and a Cretaceous sandstone are presented since the results demonstrate some of the capabilities of the device and show some of its characteristics.

Jan 1, 1971

By John Dresser

General THE controlling supply of asbestos for the world is obtained from southern Quebec, 150 miles or less north of the international boundary line between Canada and the United States, and about 75 miles south of the city of Quebec. The principal production is furnished by eight mines, seven of which occur within a distance of 6 miles, but there are also several smaller properties in the vicinity. The industry was begun in a small way some 35 years ago and has advanced more or less regularly ever since. The annual production now exceeds 100,000 tons and its value is about $3,000,000. It represents over 80 per cent. of the world's production. History Asbestos has been known in the eastern townships of Quebec since 1847, when attention was called to it in an official report by Sir William Logan, the first Director of the Geological Survey of Canada, but it was not until 30 years later that it came into commercial importance. The largest deposits, those of Thetford and Black Lake, were found in 1877 during the construction of the Quebec Central Railway. Work was begun upon them almost at once and has been continued ever since. The Danville mine, the next largest producer, was opened in 1879, and the slip-fiber deposits of East Broughton were located shortly afterward. For the first 15 years only the "crude" asbestos was recovered; that is, fiber long enough to be extracted by hand cobbing. Although this is still a valuable part of the production, it is now a relatively small part of the total output.

Jan 9, 1914

By John Suman

DURING the past few years the taking of cores in drilling with rotary equipment has been perfected to a remarkable degree in the Gulf Coast fields of Texas and Louisiana. Taking of cores is becoming quite a common thing, especially in the newer fields, and drillers are becoming expert in this work. The writer has seen cores 5 to 8 ft. long taken with great ease in wells as deep as 4500 ft. Coring is doing much to remove the prejudice which so many petroleum engineers seem to have against .the use of rotary drilling equipment for exploratory work. Some operators .are now claiming that when used with a reasonable amount of coring the rotary system is even more satis-factory than cable tools for exploring in certain territory. A case has recently been pointed out in the South Electra field of North Texas, where producing oil sands, passed over by cable-tool drillers, are being brought in with rotary equipment. It seems that in this particular territory the sands are rather thin. Cable-tool drilling was carried on for the most part in a wet hole and the red mud encountered in drilling caved into the hole very badly, so that the cuttings showed mostly red mud and the driller, thinking that the sand did not amount to anything, carried his water string through the sand. The later .operators, drilling into the sand with rotary equipment and coring it, found that it was well worth testing.

Jan 10, 1922

By Janshi Sen

VERTICAL-INTENSITY magnetometers, such as the Hotchkiss Superdip and the Askania vertical field balance, are now [ ] widely used, because vertical-intensity charts give definite information for the location of upper pole, dip and strike, and approximate shape of the deposit. Again, a slow and steady increase of dip over a large area indicates a large deep-lying deposit, while a large dip limited to a small area and falling away rapidly suggests a small and shallow one. The complication comes more from the richness of the ore. A large body of lean ore near the surface might produce the same vertical-intensity chart as a rich ore at depth. This paper presents a method for calculating the maximum depth of a single-pole deposit and another for a two-pole mineral body, by utilizing data of both vertical and horizontal intensities as obtained by a Thalen-Tiberg magnetometer. As shown on the left side of Fig. 1, lean ore, rich ore and a single pole produce the same magnetic field. The depth of the pole, [ ] h, can be calculated from the following relation: [h=a=tan¢=G-F h=aXFy] where G is the vertical intensity at point A due to the pole; F, the horizontal intensity of the same; and a, the distance from the point of maximum vertical intensity or the vertical projection of the pole on the surface to the point of observation A. If an entirely covered deposit is indicated by magnetic measurements and boring cost estimated from the calculated depth is so reasonable as to encourage drilling, the ore should be struck somewhere within the limit of the calculated depth by the borehole. A number of such points as A should be taken for calculation, erratic results should be rejected and the average figure used for cost estimation.

Jan 1, 1944

By C. WIFLARD HAYES

(New Haven Meeting, February, 1909.) I DESIRE to make it perfectly clear at the outset that I fully realize the hazardous nature of any attempt to estimate the quantity of iron-ore or any other mineral in the ground. I should not have had the temerity to venture upon an inventory of the iron-ore supplies of the United States except for the requirements of the Conservation Commission. During the preparation of this inventory I have been impressed by the wide diversity in estimates of those best qualified to. hold an opinion, and I am therefore prepared in advance for criticism of my figures. Inasmuch as this report was prepared in large part for unprofessional readers, I considered it necessary to classify and describe the commercial iron-ores in a somewhat elementary manner, in order to explain the reasons for the large element of uncertainty in the estimates. I have therefore given a chemical and a geological classification of iron-ores, which place the commercial deposits in six classes: (1) magmatic segregations in basic igneous rocks; (2) contact-deposits formed in connection with igneous intrusions; (3) concentration-deposits; (4) replacement-deposits; (5) bedded-deposits, and (6) gossan-deposits. The iron-ores are further distinguished under two classes available and not available. This classification is in large measure arbitrary, and it, is evident that it will vary front time to time. In the available class are placed those ores which can be worked at a profit under conditions essentially as they exist at present. Since it depends wholly on the question of costs, the various factors which affect cost will determine the classification of any particular deposit. Actual production, * Abstract of Report prepared for the Conservation Commission. t Chief Geologist, United States Geological Survey. .

Apr 1, 1909

By J. G. Baragwanath

CUBA'S lateritic iron ores, occurring on the northern coast of that island, though known to the Spaniards. did not receive any general attention until the close of the Spanish-American War. Preliminary studies of these deposits at that time indicated that the limonite contained small percentages of nickel and chrome, and it ryas subsequently discovered that although the average nickel content was only approximately 0.6 per certain limited areas of ore were suffiniently high in nickel to be considered commercial provided a suitable process fur its recovery could be developed. Early in 1937, Pardners Mines Corp. began a series of investigations which led to the development of such a process. Coincidentally, this company acquired option' on certain properties in the Levisa Bay and Moa Bay regions and conducted a systematic campaign of exploration by test pits and hand-auger holes in the course of which an aggregate of 90.000.000 tons of ore was developed in eight deposits.

Jan 1, 1945

By E. D. Peters

It frequently occurs in the establishment of reduction works, in an entirely new and untried mining district, that the metallurgist in charge finds considerable difficulty in determining the process best adapted to the ores which he receives for treatment. At the first glance it would seem easy enough to decide what style of furnace is best adapted for beneficiating any one class of minerals. If the ore possessed a quartzose gangue and was comparatively free from base metals, while salt could be obtained at a reasonable price, one would naturally resort to a chloridizing roasting, and pan or barrel amalgamation for the extraction of its silver contents. If galena or carbonate of lead was the prevailing mineral, and charcoal could be obtained at moderate figures, the blast-furnace would beneficiate the ores most advantageously. But if, as is usually the case in Colorado, the ores consisted of an intimate mixture of galena, zinc-blende, copper-pyrites, and noble silver minerals, associated with an overwhelming mass of siliceous heavy spar, or limestone gangue, the common reverberatory furnace can be used to the greatest advantage ; and, although the product is only a copper matte, I do not hesitate to affirm that it can be treated, and the silver, gold, and copper produced at nearly the same price for which silver and lead can be separated. In Germany, blast-furnaces are frequently used for this same purpose, both for argentiferous and non-argeutiferous copper ores; but any one who will take the trouble to examine the statistics of smelting at Fahlun, the Oberharz, and other Continental works of this description, will see that the expenses are far too great, and the production much too small to think of employing this method in our mining districts, where only the softest and most miserable kind of charcoal is obtainable. I propose in this paper to give an accurate account of the expenses incurred at the Mount Lincoln Smelting Works in treating the same kind of ore, and producing the same end-product in both blast and reverberatory furnaces. I have taken for comparison a favorable campaign of the blast-furnace, and a good average month's running of the reverberatory. In the blast-furnace estimate I have included the calcining and concentration of the matte produced during that campaign, as I always, when possible, concentrated the regulus made

By Howard Eavenson

IN a discussion in the Transactions of the Institute (vol. xl, page 835 et seq.) the writer gave some data about explosions of gas and dust in the coal mines of the United States, Canada, and Mexico, among which was a table showing all explosions in the countries mentioned, in which five or more fatalities occurred, which had been reported from Oct. 2, 1871, to Mar. 28, 1908. Since the elate of publication of this discussion, as opportunity has presented, this table has been extended by the addition of explosions occurring since that time, by including several explosions which occurred prior to 1871, and by adding to the list all explosions of gas or dust in which less than five fatalities occurred, this having been clone by a search through the various mine reports, partly by the author and partly by the Librarian of the United Engineering Societies, and by correspondence with mine inspection officials of the various States, to all of whom acknowledgment of assistance is made: The accompanying list, Table I, is believed to be as nearly correct as such a statement can be made, and, while only extending to Dec. 20, 1912, contains all of the data now available in reports. An analysis of Table I, showing the occurrence by months of all explosions of gas or dust, including those in which less as well as those in which more than five fatalities occurred, is given in Table II. The statements are frequently made, in technical papers, that the number of explosions, particularly the larger ones, is increasing more rapidly than the number of mines, and that the number of fatalities caused by mine explosions, particularly the more disastrous ones, is increasing faster, proportionally, than the production of coal. To investigate the correctness of these statements Table III was prepared, in which the number of accidents and fatalities is taken from Table I, using those in the United States only, on account of lack of other data for Canada and Mexico; the production is from the records of the U.S. Geological Survey, and the number of mines, from 1909, from the same source; previous to 1909, the number of mines, for the decennial periods, was furnished by the U. S. Census records.

Jan 10, 1914

By F. E Turton

THE town of Rancagua, at the junction of the state and Braden Copper Co. railroads, is located 82 km south of Santiago, the capital of Chile. From Rancagua 70 km to the east, situated in the Andes at an elevation of 7000 ft, is the town of Sewell, the location of a millsite. Two and one half km east of Sewell by underground railroad at an elevation of 7500 to 10,000 ft is the Teniente ore-body. The history of El Teniente dates from the eighteenth century, when according to legend a Spanish lieutenant, or teniente, a fugitive from justice, escaped to the Andes and camped at what afterwards became known as the Mineral El Teniente. This man reputedly discovered a vein of high grade copper ore. The first official records date from 1819, when some exploitation was begun, and continue until 1870. The orebody was large and of relatively low grade and was beyond the capabilities of the small groups attempting to operate it. No effort was made to erect a concentrator until William Braden became interested in the property. In 1901 Mr. Braden promoted the necessary capital for the first practical exploitation of the ore-body. Barton Sewell and E. W. Nash, both of the

Jan 1, 1953

By F. E. Turton

THE town of Rancagua, at the junction of the state and Braden Copper Co. railroads, is located 82 km south of Santiago, the capital of Chile. From Rancagua 70 km to the east, situated in the Andes at an elevation of 7000 ft, is the town of Sewell, the location of a millsite. Two and one half km east of Sewell by underground railroad at an elevation of 7500 to 10,000 ft is the Teniente ore-body. The history of El Teniente dates from the eighteenth century, when according to legend a Spanish lieutenant, or teniente, a fugitive from justice, escaped to the Andes and camped at what afterwards became known as the Mineral El Teniente. This man reputedly discovered a vein of high grade copper ore. The first official records date from 1819, when some exploitation was begun, and continue until 1870. The orebody was large and of relatively low grade and was beyond the capabilities of the small groups attempting to operate it. No effort was made to erect a concentrator until William Braden became interested in the property. In 1901 Mr. Braden promoted the necessary capital for the first practical exploitation of the ore-body. Barton Sewell and E. W. Nash, both of the

Jan 1, 1953

By AIME AIME

PRESIDENT BASSETT'S gavel called the Annual Business Meeting to order shortly after 10 a. m. on Tuesday. On motion of Eugene McAuliffe, reading of the minutes was dispensed with and Mr. Bassett read his annual report of the year's activities as follows : During the year I have visited eighteen of the twenty- seven sections, making an average of GG 2/3 per cent. The invitation to come again has always been extended, but in only one case have I been able to visit the same section twice. Chicago entertained the president twice during 1930. Mrs. Bassett accompanied me on visits to ten sections. Everywhere we have found the most cordial hospitality and a gratifying enthusiasm for the Institute. If anyone had fault to find with the management or felt dissatisfied with what was being done, it was carefully concealed. I am happy to report to you an agreeable, helpful and progressive spirit in each of the sections visited.

Jan 1, 1931

By Basil B. Zavoico

During 1938 the Russian oil industry, while able to increase its production 4.69 per cent above the preceding year, was not successful in correcting some of its basic difficulties, and the industry's position as it entered 1939 was unsatisfactory. The internal political difficulties of 1937 and 1938 took a toll in the oil industry as they did elsewhere in the U. S. S. R., further complicating the solution of the problems facing it, most important of which still remain: lack of experienced and responsible leadership, able to make quick decisions; undisciplined and migratory labor; and insufficient and often unsatisfactory quality of the various equipment needed by the industry and its ineffective distribution. Recent developments in the U. S. S. R. suggest that during 1939 the management will be granted more latitude and hence somewhat better results may be anticipated from the executive branch, provided, however, the "purges" do not recur. The labor should be better disciplined and should not shift as easily, owing to the introduction, at the close of 1938, of individual labor passports to all workers in the country, the principal purpose of which is to correct those two deficiencies. It is not anticipated, however, that the service of supply will show any appreciable improvement in 1939, partly because of inherent difficulties and partly because the manufacturers of heavy machinery are working primarily and necessarily for munitions. Production Production of crude oil during 1938 is estimated at 224,714,000 bbl., as compared with 212,742,000 bbl. in 1937, an increase of 4.69 per cent but 12.76 per cent below the planned output. While there were no major readjustments in the source of supply of crude oil, both the older districts, Baku and Grozny, were barely able to maintain their 1937 levels of production, the increased output being supplied primarily by the fields of Maikop and Ural Permian Basin districts. While exploration work was outstandingly successful in 1937, in 1938 no discoveries of any

Jan 1, 1939

By Basil B. Zavoico

During 1938 the Russian oil industry, while able to increase its production 4.69 per cent above the preceding year, was not successful in correcting some of its basic difficulties, and the industry's position as it entered 1939 was unsatisfactory. The internal political difficulties of 1937 and 1938 took a toll in the oil industry as they did elsewhere in the U. S. S. R., further complicating the solution of the problems facing it, most important of which still remain: lack of experienced and responsible leadership, able to make quick decisions; undisciplined and migratory labor; and insufficient and often unsatisfactory quality of the various equipment needed by the industry and its ineffective distribution. Recent developments in the U. S. S. R. suggest that during 1939 the management will be granted more latitude and hence somewhat better results may be anticipated from the executive branch, provided, however, the "purges" do not recur. The labor should be better disciplined and should not shift as easily, owing to the introduction, at the close of 1938, of individual labor passports to all workers in the country, the principal purpose of which is to correct those two deficiencies. It is not anticipated, however, that the service of supply will show any appreciable improvement in 1939, partly because of inherent difficulties and partly because the manufacturers of heavy machinery are working primarily and necessarily for munitions. Production Production of crude oil during 1938 is estimated at 224,714,000 bbl., as compared with 212,742,000 bbl. in 1937, an increase of 4.69 per cent but 12.76 per cent below the planned output. While there were no major readjustments in the source of supply of crude oil, both the older districts, Baku and Grozny, were barely able to maintain their 1937 levels of production, the increased output being supplied primarily by the fields of Maikop and Ural Permian Basin districts. While exploration work was outstandingly successful in 1937, in 1938 no discoveries of any

Jan 1, 1939

By I. Cadoff, J. P. Nielsen

The Ti-C phase diagram exhibits a peritectic point at 1750°C and 0.8 pct C, and a peritectoid point at 920°C and 0.48 pct C. The maximum solubility of carbon in a titanium is 0.48 pct. The 6 region containing the Tic compound (20 pct C) extends to 11 pct C at the peritectic temperature. THE interest in the Ti-C alloy system stems from the fact that carbon occurs as an impurity in titanium alloys when graphite electrodes or graphite crucibles are used in their melting. Since titanium-base alloys are still in the development stage, some virtue may be found in carbon addition to titanium. The Tic compound is currently emerging as an important powder metallurgy base constituent similar to the WC compound. Ehrlich' identified the phases and structures present in the Ti-C system. The peritectoid region of the phase diagram was investigated by Jaffee et al." A preliminary diagram based on theoretical considerations was proposed at the outset of this research." The Tic compound has been investigated extensively and has been reported on in a large number of papers. Experimental Procedure Arc-melted alloys of 24 compositions in the range 0 to 20 wt pct C were investigated using metallography, X-ray diffraction, and, for the liquidus and solidus regions, incipient and complete melting. All alloys were prepared from iodide titanium (New Jersey Zinc Co., 99.95 pct Ti minimum) and spectroscopic grade carbon (National Carbon Co.). To prevent carbon spattering during arc melting the carbon was encapsulated in titanium. For alloys containing less than 1 pct C the powder was inserted into a capsule formed by drilling a hole in the as-received rod. For higher compositions, capsules were formed from titanium sheet. Arc Melting: The charges were melted in the copper-hearth cold electrode furnace shown in Fig. 1. This furnace is similar in principle to the all-metal unit adapted for titanium melting at Battelle Memorial Institute.' The transparent pyrex walls giving unlimited visibility during operation and the multiple-

Jan 1, 1954

Since 1571, when the Institute was founded, many of the most important papers in the English language, on the various phases of mining and metallurgy, have appeared as Institute publications. As members of the Institute regularly receive the publications in which they are interested, this discussion is primarily for nonmembers who wish to know of them. The Institute has several means of issuing papers which have been submitted and accepted. The monthly journal, Mining and Metallurgy, is the magazine of the Institute. In it appear notices and reports of official business as well as many papers and contributions which do not appear otherwise. The annual subscription price of the magazine to nonmembers is $3 per year; Canadian and foreign postage $1 extra; single copies 50 cents; back issues $1 each. Many papers are published separately each year. They are issued in one or the other of two numbered series; namely, Technical Publications and Contributions, and of the latter there are four forms: Preprints, Mimeographs, Reprints, and Unpublished Manuscripts. A Technical Publication or Contribution (in any form) is issued by the Institute when it is listed in Mining and Metallurgy. Technical Publications are sent automatically to members who have asked in advance for papers on a given subject. All members are entitled to a copy of every paper in either series, except when a Contribution is an Unpublished Manuscript. Con¬tributions in the form of Unpublished Manuscripts are filed in the Engineering Societies Library and copies of some of these papers may be found in a few selected libraries throughout the country.

Jan 1, 1933

By AIME AIME

UNTIL recently, practically all geophysical prospecting in Australia was conducted by government departments, either by the Aerial, Geological and Geophysical Survey of Northern Australia or the New South Wales Department of Mines. At present, in addition, the Shell company is carrying out an extensive geophysical campaign in South West Queensland. The Northern Australia Survey has now been in operation for over six years, its work being carried out principally in the northern and central parts of Australia over an area of about a million square miles. At present this Survey is being brought to a conclusion but it appears certain that the geophysical section will be transferred to a Commonwealth Government department on a permanent basis. At present the officers of the Geophysical Section are preparing or have issued some 150 reports on their field work and also a special technical report on the geophysical practice of the Survey.

Jan 1, 1942

By J. R. Linney

A HISTORY of the ore-mining and iron-smelting industry of the Adirondacks comprises a century and a half of pioneering by rugged individualists, both men and women. By geographical location, the climate is most severe-long, cold winters with heavy snowfall, and short seasons of vegetation growth; this, together with its remote location from large centers of population, adds considerably to the difficulties of conducting mining operations in this area.

Jan 1, 1943

By P. H. Griffin

WHEN a subject, such as the manufacture and service of chilled car wheels, as has been fruitlessly discussed for ten or fifteen years, it is difficult to revive interest and action by the mere repetition of statements and arguments that have been made before. And when a situation involves serious responsibilities for conditions that have grown up under circumstances beyond the control of any particular individuals or authority, it is even more difficult to deal with. But there is one phase of every subject that need not involve these particular points if presented in a, proper manner; and that is, " the future state." I will try to present the subject of this communication from the latter standpoint and with the hope that all of those interested will feel disposed to give the matter attention from the basis that it is a, vitally important one to all that travel on railroads, whether as employees or officials, or as dependent on those in charge of the operation, or in the matter of materials and equipment used. The conditions of chilled wheel service have been changed so radically in the past ten or fifteen years by the use of freight cars of 40 and 50 tons capacity, that it is fair to say in the interest of all concerned in the use and in the manufacture of such wheels, that the increased strains and loads have been quite sufficient to account for much of the service results that have transpired. That proper provision was not made for increased possibilities of strength and wear, in fact that previous factors of the kind were allowed to deteriorate, is no proof that such wheels cannot be made equal to heavy service conditions as shown in the data given herein.

Jan 10, 1913