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By John Fulton

THE increase in the production of iron has been accompanied by a growing demand for an improved quality, and more especially at the present time, in the manufacture of Bessemer steel, which is rapidly becoming an important branch of industry. This has led the makers of pig iron to a careful investigation of the composition of the materials from which their metal is produced, the inquiry being greatly assisted by a cordial alliance of science and practice. Formerly, chemical science was held in abeyance, or admitted in a hesitating experimental way ; but now it is received as a valuable auxiliary, and its decisions are accepted as final and conclusive. It is called on to assist the iron-maker in determining the quality of his stock, and to detect the presence of injurious elements in his fuel, ores, flux, or iron. The object of this paper is to submit the method now in use at the furnaces of the Kemble Coal and Iron Company in the Broad Top coal and iron region, for removing, by a process of crushing and washing, slate and other impurities from coal, designed, when coked, for furnace fuel. It is not contemplated to claim very advanced progress in this work, believing that it is susceptible of improvement, but to show that some progress has been made in a comparatively new field, and it is hoped in the right direction, since coke is probably destined to become the principal fuel in the metallurgy of iron. The Broad Top coal region occupies an isolated geographical position, standing 25 miles east from the Alleghany field. It is associated with the latter by the structure of its coal, and more closely with the Cumberland field by a similarity in the quality of coal.

(Under. this heading will he published notes sent to the Secretary of the Institute by members or other persons introduced by members.) Member; age 31, technical graduate, 8 years' experience in copper and nickel mining, desires to make a change. No. 480. Member, age 34, married, 16 years' experience as railroad construction engineer and as superintendent of iron, chrome and manganese mines. Especially successful in rush construction work and development of new mining properties. No straight salary proposition will be considered. No. 481. Member desires change of position. Four years experience in flotation, cyaniding, and mill design and construction. Married, technical graduate. No. 482. Member, age 33, married, graduate Columbia School of Mines. Nine years' experience as engineer and mining and oil geologist; experience in Mexico, Peru and Siberia. Speaks Spanish and Russian. No. 483.

Jan 9, 1918

By T. S. Maio, J. G. Mansanti

In 1978, Ozark Lead Co. made the decision to expand the capacity of its mine/mill complex by 33%. The objectives of the expansion were to increase mine production capacity by 1.8 kt/d (2000 stpd), increase lead metal production by 21.8 kt/a (24,000 stpy), and to construct new facilities and modify existing equipment to accommodate increased production. This paper gives a brief explanation of the equipment installed and the overall production and metallurgical benefits realized from this expansion. The expansion was completed in the second half of 1980 with all equipment debugging and fine tuning completed by the first quarter of 1981. Concentrator modifications and improvements were basically restricted to four areas: materials handling, automation of the mill grinding circuit, increased flotation capacity, and concentrate dewatering.

Jan 1, 1985

By Thomas M. Drown

At the meeting of the Istitote in New York, in February, 1880," I described a process of determining sulphur iu metallic allphides, with especial reference to the determination of pyrites in coal. The procem, as then described, is as follows: A solution of sodium hydrate, of 1.25 specific gravity, is saturated with bromine. If an excess of bromiue is used it must be neutralized by the addition of a little more sodium hydrate. The pulverized mineral or coal is moistened with 25 c.e. of this solution autl heated, then hydrochloric acid is added cautiously to just acid reaction. This operation is repeated with another 25 c.c. of the alkaline solution, and again rendered acid. The mixture should be kept hot. The contents of the beaker or dish are then

Jan 1, 1881

By Fred Mosley

The present operation is located on Whitewood Creek about two miles downstream from Deadwood, South Dakota. Early day placer gold operations took place on this creek from Crook City to an area several miles upstream from Deadwood. Early discoveries were in the Deadwood area. In this particular zone, much of the early work was accomplished at stream level and at various elevations above. In the original operations, it was not possible to reach bedrock in many places due to the ground water level plus the existence of numerous large boulders in the same area. The bedrock in this area is approximately twenty feet deep, consisting of Cambrian and Ordovician sediments. Shortly after the early operations began, many small lode mines and several larger mines released mill tailings directly into Whitewood Creek. This practice continued for a full century, thereby limiting the amount of clean water available for sluicing. These tailings in the stream carried large amounts of heavy minerals along with the natural heavier minerals introduced from erosion and were immediately caught in the riffle boxes, resulting in the suspension of many small sluicing operations. No large scale sluicing or mining was ever done at bedrock level in this area, resulting in an almost virgin placer gold deposit. The old tailings cover much of the area, contributing an additional deposit carrying appreciable gold values. In recent years, a company known locally as New Era Mining Company attempted with some success to exploit the area at bedrock level. The equipment used included a Marian dragline with. a three- yard bucket, a washing trommel mounted on a 40 ft by 20 ft floating pontoon barge, together with two banks of Humphrey Spirals and a secondary spiral for collecting concentrate from the two primary

Jan 1, 1983

` LAWRENCE ADDICKS, New York, N. Y.-We have really two competitive processes for the production of electrolytic zinc. In the process used at Great Falls, the ore is roasted and the calcines leached, leaving a residue which has to be smelted; in the other method, the ore is burned, the zinc and lead fumed off, and the condensed fumes are leached. I do not think that we can yet come to any decision as to which is the better way to attack the problem. Of course if we roast first and then leach, various substances remain in the calcines which may consume sulphuric acid; whereas if we do the burning first, we obtain simply the zinc and lead oxides, with considerable sulphate, in the fume, and there is no shortage of acid. It also depends partly on the complexity of the ore. The one that Mr. Hall is treating and the ore they are treating at Great Falls are not quite alike, but I think they are sufficiently similar to make a comparison of the two methods, working in competition, on different parts of the country, very interesting. C. E. SCHWARTZ, Miami, Okla.-Mr. Hall states that the Joplin conditions are not suitable for the manufacture of electrolytic zinc. When we speak of Joplin ore in general, we consider, of course, a 60-per cent: concentrate with comparatively low iron, but if a low-grade concentrate could be made from tailings and so-called chats, then the problem would be quite different. A Joplin ore is comparatively simple to treat electrolytically, and I believe the electrolytic process would open a field for the treatment of such ores as would not be ordinarily smeltable; that is,

Jan 1, 1918

By Frank Rieber

THE study of earthquakes long ago developed the fact that by studying the travel times of the various groups of waves from the same earthquake, as received on seismographs at varying distances, major discon-tinuities in the earth's crust could be reasonably well defined. Using this original discovery, and adapting the mathematical methods originally devised in seis-mology for determining the depth below the surface at which such discontinuities occur, other investigators were able to develop a new branch of seismology which promises to be extremely useful in extending the boun-daries of our information oil local conditions below the earth's surface. As an outstanding example of the applications of this work, we have the so-called "seismo-graph" exploration of the Gulf Coastal region, which has resulted in the discovery of a large number of salt domes, from many of which oil fields may be developed. The original seismological investigations, from which different major discontinuities in the earth's crust were deduced, as well as these later successful experiments in finding salt-dome structures, involve relatively simple problems. In each case we are dealing with surface materials in which elastic waves will be propagated with a fairly definite velocity. Under this material we have something very different, in which the elastic waves will be propagated with a much higher velocity. The transition from one medium to another is like-wise relatively abrupt. For example, in. the Gulf Coastal region the sedimentary formations have a velocity of 6000 or 7000 ft. per sec., while the velocity of elastic waves in the cap rock of a salt dome" may exceed 15,000 ft. per sec. Under such conditions, de-lineation of the formation is a relatively simple matter, and, furthermore, there is very little opportunity for ambiguous results.

Jan 9, 1928

By George A. Bell

THE mine and milling plant of Demonstration Gold Mines, Ltd., is near the city limits of Baguio, Mt. Province, P. I. The mine road connects with the main highway to Manila. The nearest railway point is near sea level, approximately 40 miles distant. The Baguio district is very mountainous and has one of the heaviest rainfalls in the world. It is therefore difficult to maintain roads or to impound tailings and mine dumps. All supplies are trucked into the district direct from Manila or the nearest railway point, which means uncertain deliveries and high freight rates. Installation of equipment is difficult and costly. The average elevation at the mine is 4000 ft. and the climatic conditions are ideal except for a three months rainy season. The company generates its own power for mining and milling operations with three 400-hp. Ruston Diesel engines direct connected to 250-kw. General Electric alternating current generators. Labor conditions have been excellent, although at present social security laws are causing some unrest. Labor receives a higher average wage rate in this district than other labor in the Islands. The company also furnishes free living quarters, hospitalization and work- men's compensation. Taxation has been reasonable up to the present time, but some of the new mining legislation may make it difficult to operate and pay dividends. The future depends largely upon the continuation of $35 gold and the political outcome in the Islands. HISTORY The Demonstration ore body was worked by the Igorots for many years, as evidenced by old stopes and fill encountered in present operations. Attention of Americans was first attracted soon after the Spanish- American war. During the building of the Benguet road to Baguio, the engineers and foreman became interested in the geology of the district.

Jan 1, 1939

By H. A. Dierks

PENNSYLVANIA's anthracite region lies in the heart of the richest and most densely populated area of the U. S. Nearly 70 million people live within a radius of 500 miles, in which 130,000 manufacturing plants employ more than 8 million workers. The region comprises some 3000 sq miles and contains 484 sq miles of coal measures, which folding and erosion have divided into four separate and distinct fields, known as the Northern, Eastern Middle, Western Middle, and Southern. One million people live in the anthracite region proper, and their prosperity depends to a great extent on the anthracite industry, which produces more than $200 million in new wealth for the U. S. each year. Nearly 80 pct of the tonnage shipped out of the region is handled by nine railroads, which depend on this traffic for a large part of their revenue. It follows that the economic health and the very existence 0: this industry is of real concern not only to the region itself but also to the state of Pennsylvania and the country as a whole. Anthracite mining is one of the oldest mineral industries in America. About 1760 burning rock or stone coal was discovered on the hillsides of northeastern Pennsylvania. Within a few years a systematic search for coal bed outcrops was under way, and hand mining was begun. At first production was very limited, since anthracite was difficult to burn and was not readily accepted as a fuel. Pennsylvania anthracite is one of the densest and hardest of all coals, and its content of volatile matter is low. Consequently it does not ignite easily and it burns without smoke. About 1808 Judge Fell of Wilkes-Barre burned anthracite in an open grate fireplace and demonstrated proper handling of an anthracite fire. From

Jan 1, 1958

By D. S. Flett, D. W. West

The solvent extraction of chromium 111 has been studied for the system Cr 111, H,SO., H,O/RNH/RNH., xylene, where the primary amine used was Primene JMT. Rate studies have shown that extremely long equilibrium times are required, ranging from 1 hr at 80°C to 20 days at room temperature. Heating the solution prior to extraction increases the rate of extraction. The variation in the amount of Cr 111 extracted is an inverse function of the acidity of the aqueous phase. Thus, the slow rates of extraction appear to be connected with the hydrolysis of the Cr I11 species. Extraction isotherms for the extraction of Cr 111 have been obtained for two sets of experimental conditions, namely at 60°C and for a heat-treated solution cooled to room temperature. The separation of Fe 111 from Cr 111 and Cr 111 from Cu 11 in sulfate solution by extraction with Primene JMT has been studied and shown to be feasible. A survey of the literature relating to the solvent extraction of chromium showed that, although many systems exist for extraction of Cr VI, only a very few reagents have been found to extract Cr 111. The extraction of Cr III by di-(2-ethyl hexyl) phosphoric acid has been reported by Kimura.' A straight-line dependence of slope —2 was observed between log D,, and the log mineral acid concentration at constant extractant concentration. Since the slope of this plot reflects the charge on the ion extracted, it must be concluded that a hydrolyzed species of Cr III is being extracted. Carboxylic acids generally do not form extractable complexes with Cr III but di-isopropyl salicylic acie does extract Cr 111. Simple acid backwashing of the organic phase, however, failed to remove the chromium. Similar difficulty in backwashing was found by Hellwege and Schweitzer8 in the extraction of Cr I11 with acetyl-acetone in chloroform. The extraction of Cr 111 from chloride solutions by alkyl amines has been reported4-' but the maximum amount of extraction achieved in these studies did not exceed 10%: From sulfate solutions, however, Ishimori" has shown that appreciable amounts of Cr I11 were extracted by amines. The amines used were tri-iso-octyl amine, Amberlite LA-1 (a secondary amine, Rohm & Haas) and Primene JMT (primary amine, Rohm & Haas). The efficiency of extraction with regard to amine type was primary>secondary> tertiary. Appreciable extraction of Cr I11 was recorded for Primene JMT as the aqueous phase acidity tended to zero. The major difficulty with Cr I11 in solvent extraction systems stems from the nonlabile nature of the ion in complex formation. This accounts for the slow rate of extraction generally experienced and the difficulty encountered in backwashing the Cr I11 from the organic phase in the case of liquid cation exchangers. Consequently, the possibility of extraction of Cr I11 as a complex anion is attractive since the backwashing problems should be minimized in this way. From published data, it appeared that the extraction of chromium from sulfate solutions of low acidity by primary amines afforded the best chance of success for a useful solvent extraction system for Cr iii This paper presents the results of a study of the extraction of Cr I11 from sulfate solution by Primene JMT and examines the application of such an extraction procedure for the recovery of chromium from liquors containing iron and copper. Experimental Chromium solutions were prepared from chrome alum in sulfuric acid and sodium sulfate so as to maintain a constant concentration of sulfate ion of 1.5 molar. Solutions of Primene JMT were prepared in xylene and the amine equilibrated with sulfuric acid/sodium sul-fate solutions, of the same acidity as the chromium solution, until there was no change in acidity between the initial and final aqueous phases. The solutions of Primene JMT conditioned in this way were then used for the equilibration experiments. Equilibrations at 25°C were carried out in stoppered conical flasks shaken in a thermostat; equilibrations at all other temperatures were carried out in stirred flasks in a thermostat. After equilibration, the phases were separated and analyzed for chromium. In the tests on the rate of extraction, small samples of equal volume of both phases were withdrawn from time to time and the chromium distribution determined. The chromium analyses were carried out either coloi-imetrically using diphenyl carbazide, or volu-metrically using addition of excess standard ferrous ammonium sulfate and back titration of the excess iron with potassium dichromate. The oxidation of Cr 111 to Cr VI in the case of the raffinate solution was effected by boiling with potassium persulfate in the presence of silver nitrate and, for the backwash solution, by boiling with sodium hydroxide and hydrogen peroxide. Results Preliminary experiments indicated that extraction results were effected by the age of the chromium solution, higher distribution coefficients being obtained with solutions which had been allowed to stand for some time. Consequently a stock solution of chrome alum, 10 m moles per 1 Cr I11 in 1.4 M Na,SO,/O.l M &SO,,

Jan 1, 1971

By Frederick F. Frick

SPONGE iron as produced at Anaconda is a fine, -35 mesh, impure product, about 50 pct metallic iron, obtained from the reduction of iron calcine at a temperature of 1850°F by use of coke resulting from slack coal. The metallic iron particles are bulky and spongey and precipitate copper readily and rapidly from a copper sulphate solution. Investigation of the treatment of Greater Butte Project, Kelley, ore at Anaconda early showed the desirability of using sponge iron as a precipitant for the copper in solution resulting from desliming of the ore in a dilute sulphuric acid solution. Anaconda had done considerable work on the production of sponge iron in 1914 for use as a precipitant of copper from leach solutions. Some success and considerable experilence were attained at the time. indicating that, sponge iron might be successfully made by a modification of the process used in 1914, a batch process in which an iron calcine was reduced by means of soft coke, resulting from noncoking coal, in a Bruckner-type revolving horizontal cylindrical furnace widely used 50 years ago. The coke and calcide formed the bed in the Bruckner furnace, which was rotated at about 1 rpm. The bed was brought to a temperature of about 1800°F by means of an oil flame over the surface. Although results were reasonably satisfactory, they did not warrant full development of the process at that time. A good deal of work has been done in the last 50 years on the production of sponge iron. The objective in some cases has been the production of a precipitant for copper from solution, but the bulk of the work has been done for the production of open-hearth steel furnace stock. The production of an open-hearth stock presents two problems rather than one: first, producticon of the sponge iron, and second, what is perhaps of equal difficulty and importance, conversion of the sponge iron into a form suitable for use in the open-hearth furnace. So far as is known to the writer, none of the sponge iron processes tried in the past have proved to be economically feasible. However, Anaconda had a combination of conditions appearing to justify an attempt to produce sponge iron which would serve for the leach-precipitation-float process. It was thought that the process used in 1914, if changed to a continuous one, might work out satisfactorily. The following favorable conditions at Anaconda justified the investigation: 1—A sufficient tonnage of good grade iron calcine resulting from the roasting of a pyrite concentrate in one of the acid plants, at substantially no cost. 2—Reasonably cheap natural gas. 3-—The fact that there was no need for production of a high grade product. 4— The fact that there was no need for obtaining a consistently high reduction of' the iron in calcine. A small revolving Bruckner-type furnace about 2 ft ID by 4 ft long was set up for early pilot work at the research building. This pilot furnace showed that a satisfactory product could be obtained at reasonable cost. It also indicated a marked advantage in preceding the reduction furnace with a furnace of similar size and capacity for preheating and roasting out any residual sulphur from the feed. The small furnace was operated for several months, various details of the process were worked out. and sponge iron was produced to supply a pilot LPF plant which treated 300 lb of Kelley ore pel- hr. Later a second pilot furnace 5 ft in diam and 12 ft long inside was set up at our reverberatory furnace building. This furnace confirmed the data of the small furnace and gave a basis for design of the final plant. At Anaconda a pyrite concentrate, running about 48 pct S, is recovered from copper concentrator tailings by flotation. This concentrate is roasted to sulphur of 3 pct or less at the Chamber acid plant. The iron calcine contains about 57 pct Fe and 18 pct insoluble. The iron calcine feed, as mentioned before, is re-roasted and preheated in a reroast furnace preceding the reduction furnace. Both are of the Bruckner type. The reroasted calcine is fed into the reduction furnace at 800" to 1000°F along with 30 pct slack coal. In the feed end of the furnace the volatile is burned from the slack, giving a soft coke which readily serves for reduction of the iron. Hard metallurgical coke will not serve the purpose. since it does not reduce CO readily at a temperature of 1850°F. All indications are that the actual reduction of the iron is accomplished by carbon monoxide below the surface of the bed, which is 30 in. deep at its center. Apparently there is a constant interchange: Fe²O³ + 3CO = 2Fe - 3CO², CO² + C = 2CO Actually iron oxide is reduced by CO at somewhat lower temperature than the 1850 °F used in the process. but this temperature is necessary to obtain a satisfactory rate of furnace production. The furnace atmosphere is generally reducing, and typical blue carbon monoxide flames satisfactorily cover the bed. Gas flames from four 3-in. Denver Fire Clay Inspirator burners are played directly on the bed, which is slowly cascaded by the 1 rpm of the furnace. An excess of coke is necessary to assure maintenance of good reducing conditions in the furnace bed. Part of this coke is recovered for re-use.

Jan 1, 1954

By J. F. Ednie

SCRAP metals to the value of more than a billion and a half dollars were recovered in the United States in 1939 for further use in industry. Few people have any true conception of the magnitude of the secondary-metal industry as related to that engaged in the production of the primary, or virgin, metals; of its importance, particularly when a shortage of primary metals exists, as at present; or of the advance that has been made in standardizing and improving the quality of its products. Of the iron and steel produced in the United States in 1939 (the data used in this article are largely taken from Bureau of Mines reports for that year) just over 50 per cent came from scrap and slightly less than 50 per cent from ore. Of the principal nonferrous metals-aluminum, anti-mony, copper, lead, nickel, tin, and zinc-63 per cent came from domestic ores and 37 per cent from scrap. Fig. 1 presents graphically the relative tonnage and value of primary and secondary production of ferrous and nonferrous metals. In this chart only purchased secondary metals are considered, the figures being exclusive of "home" or "plant" scrap which amounts to rather large figures in the iron and steel industry. Incidentally, the chart shows that from the tonnage standpoint the iron and steel industry is some twenty times larger than the nonferrous industry, though with regard to the value of the product the ratio drops to about two to one.

Jan 1, 1941

Production of crude oil in Bahrein Island during 1938 reached the new high of 8,297,998 bbl., an increase of 535,734 bbl, over the 1937 production of 7,762,264 bbl. The monthly average during 1938 was 691,500 bbl. and the daily average 22,734 barrels. To the close of December 1938, a total of 52 producing wells have been drilled. During the year 13 producing wells were completed and 11 wells were drilling or partly completed as of Dec. 31, 1938. The total footage drilled as of Dec. 31, 1938, amounted to 165,339 ft., of which 60,739 ft. was drilled during 1938. The production from the main pay comes from a depth of approximately 2200 ft. and the gravity of the oil is 33" A.P.I.

Jan 1, 1939

Production of crude oil in Bahrein Island during 1938 reached the new high of 8,297,998 bbl., an increase of 535,734 bbl, over the 1937 production of 7,762,264 bbl. The monthly average during 1938 was 691,500 bbl. and the daily average 22,734 barrels. To the close of December 1938, a total of 52 producing wells have been drilled. During the year 13 producing wells were completed and 11 wells were drilling or partly completed as of Dec. 31, 1938. The total footage drilled as of Dec. 31, 1938, amounted to 165,339 ft., of which 60,739 ft. was drilled during 1938. The production from the main pay comes from a depth of approximately 2200 ft. and the gravity of the oil is 33" A.P.I.

Jan 1, 1939

By H. F. Smiley, Fred Sehmann

The production of the North Central Texas area comes entirely from the Pennsylvanian section with the exception of one pool in Cooke County and one in Young County where oil has been, produced from the weathered surfaces of Pre-Pennsylvanian peaks overlapped by oil-bearing strata of Pennsylvanian age. In the southern part of the area the Strawn and Bend groups furnish the production, the Strawn sands being the predominating horizons at depths from 1500 to 3000 feet. In the northern part of the area including North Young, Archer, Wichita, Wilbarger, and Clay counties, the Cisco group has produced consistently for nearly 30 years from sands ranging in depth from 700 to 2500 ft. To our knowledge there are 13 separate producing sands in t,he Cisco group ranging from 200 to 1800 ft. in Wichita County. During the past three years, deeper drilling has opened three new producing horizons. A Canyon sand in Central Archer County has produced from 400 to 800 bbl. per well at a depth of 2200 ft.; and in the same pool, owned jointly by the Deep Oil Development Co. and Lindsay Drilling Co., a Strawn sand was found at 3600 ft. which produced 75 bbl. per day. In Southern Wichita County the Bend group has been found productive. A very oolitic sandy lime series from 3675 to 3942 ft. has produced in three wells drilled to date. During the past year the district has been producing under an extreme proration which accounts for the small production figures for 1932, as well as the few drilling activities at the end of the year. Table 1 presents the available drilling and production data compiled by the North Texas Oil and Gas Association.

Jan 1, 1933

By A. D. David

The object of this paper is to reduce to the simplest possiblc discussion the recent developments in refinery technology without resorting to detailed technical descriptions of the various items. During the year 1929, the most noteworthy tendencies have been towards the installation of more flexible plants, more unified operations, more balanced performance and greater fuel economy. In no other year in the history of petroleum refining has the industry witnessed to as great a degree the crystallization of so rnany developments in almost every phase of the art. Economic pressure has been the controlling factor, supplemented however by a market demand for more volatile anti-knock gasoline and higher quality of lubricating oils, resulting from the extended use of high-compression motors. Catalytic Hydrogenation Possibly the outstanding achievement during the year has been the beginning of construction of plants by the Standard Oil Co. of New Jersey for the catalytic hydrogenation of the so-called heavier and inferior petroleum oils to produce therefrom not only high yields of anti-knock gasoline, but also lubricating oils equal in quality to the best grades obtainable. It is reported that the plants will operate at a pressure of 4000 lb. or higher and temperatures in excess of 900" F. will be used. The hydrogen required for the conversion will be produced from refinery gases. This type of processing will doubtless be an important factor in balancing future operations; in other words, it can be used to eliminate present waste products and permit production of high-grade products from low-grade crude. Improvements in Lubricating Oils Another important development during the past year has been the extended use of vacuum stills, making possible the production of lubricating oils from what was formerly classed as "fuel-oil crude," or crude from

Jan 1, 1930

By Joseph E. Pogue

New economic forces are at work in the petroleum industry. In order to visualize these forces and to see clearly their bearing upon the producer, refiner, and marketer, it is necessary, first, to go back and gain a perspective of the economic evolution of the business. Early Trend to Integration For several decades prior to 1911, the outstanding feature of the petroleum industry was a trend toward integration, culminating in a huge combine, the Standard Oil Co. An important aspect of this integrative trend, however, was its concentration upon a combination and control of refining and marketing, leaving crude oil production, for the most part, to the exigencies of small-unit competition. It is a noteworthy coincidence that during this era the law of oil and gas was formulated and applied, whereby these substances had to be reduced to possession to establish ownership; and the forces of competition in crude oil production were thereby intensified. It was to the interest of an industry, safeguarded in its control of manufacturing and markets, to have supply stimulated by legal convention as well as by individual initiative in order that the growing demand could be met without interruption. And so overproduction of crude oil during this era was no handicap, but rather an aid, to the progress of the industry. Disintegration But the idea of superintegration, despite its efficiencies, became repugnant to the temper of the times and so the Standard Oil Co. was dissolved by Court decree—disintegrated into over 30 parts. And thus, in 1911, was ushered in the second era of the petroleum industry, a period of intense competition. This era coincided with the development of automotive transportation, and a tremendous growth resulted in the effort to keep pace with the mounting demand for gasoline. An intense individualism and unbridled competition were appropriate to this period of entry

Jan 1, 1930

By George A. Bell

The mine and milling plant of Demonstration Gold Mines, Ltd., is near the city limits of Baguio, Mt. Province, P. I. The mine road connects with the main highway to Manila. The nearest railway point is near sea level, approximately 40 miles distant. The Baguio district is very mountainous and has one of the heaviest rainfalls in the world. It is therefore difficult to maintain roads or to impound tailings and mine dumps. All supplies are trucked into the district direct from Manila or the nearest railway point, which means uncertain deliveries and high freight rates. Installation of equipment is difficult and costly. The average elevation at the mine is 4000 ft. and the climatic conditions are ideal except for a three months rainy season. The company generates its own power for mining and milling operations with three 400-hp. Ruston Diesel engines direct connected to 250-kw. General Electric alternating current generators. Labor conditions have been excellent, although at present social security laws are causing some unrest. Labor receives a higher average wage rate in this district than other labor in the Islands. The company also furnishes free living quarters, hospitalization and workmen's compensation. Taxation has been reasonable up to the present time, but some of the new mining legislation may make it difficult to operate and pay dividends. The future depends largely upon the continuation of $35 gold and the political outcome in the Islands. History The Demonstration ore body was worked by the Igorots for many years, as evidenced by old stopes and fill encountered in present operations. Attention of Americans was first attracted soon after the Spanish-American war. During the building of the Benguet road to Baguio, the engineers and foreman became interested in the geology of the district.

Jan 1, 1939

By George A. Bell

The mine and milling plant of Demonstration Gold Mines, Ltd., is near the city limits of Baguio, Mt. Province, P. I. The mine road connects with the main highway to Manila. The nearest railway point is near sea level, approximately 40 miles distant. The Baguio district is very mountainous and has one of the heaviest rainfalls in the world. It is therefore difficult to maintain roads or to impound tailings and mine dumps. All supplies are trucked into the district direct from Manila or the nearest railway point, which means uncertain deliveries and high freight rates. Installation of equipment is difficult and costly. The average elevation at the mine is 4000 ft. and the climatic conditions are ideal except for a three months rainy season. The company generates its own power for mining and milling operations with three 400-hp. Ruston Diesel engines direct connected to 250-kw. General Electric alternating current generators. Labor conditions have been excellent, although at present social security laws are causing some unrest. Labor receives a higher average wage rate in this district than other labor in the Islands. The company also furnishes free living quarters, hospitalization and workmen's compensation. Taxation has been reasonable up to the present time, but some of the new mining legislation may make it difficult to operate and pay dividends. The future depends largely upon the continuation of $35 gold and the political outcome in the Islands. History The Demonstration ore body was worked by the Igorots for many years, as evidenced by old stopes and fill encountered in present operations. Attention of Americans was first attracted soon after the Spanish-American war. During the building of the Benguet road to Baguio, the engineers and foreman became interested in the geology of the district.

Jan 1, 1939

By J. Mizrahi, A. Brillantshtein, A. Mitzmager, O. Schächter

The separation of synthetic mixtures of heavy minerals by hindered settling classification and jigging was comparatively tested in water and five organic heavy liquids, of various specific gravities and viscosities. It was found that in the hindered settling classification process the separation efficiency was directly proportional to the concentration criterion, the liquid viscosity being a minor factor. There is therefore a decisive advantage in using heavy liquids as classification medium. In the jigging process the advantage of using a heavy liquid is masked by the detrimental effect of a higher liquid viscosity, which, in this case constitutes an important factor. Considerable interest has been aroused lately by the development of mineral beneficiation techniques 1,2 using TBE (tetrabromoethane), a heavy liquid of specific gravity of 2.96, which has been made available for industrial use by a new process3 producing TBE directly from the Dead Sea brines at a reasonable price. Most of the applications investigated until now were based on the sink-float separation of minerals in a heavy liquid of intermediate specific gravity. The TBE can be conveniently diluted with many organic solvents, and thus sharp separations are possible in a wide range of specific gravities up to 2.96. Although this maximum specific gravity is sufficient on most cases for the elimination of the bulk of the barren gangue and the production of marketable concentrates, some practical problems came up for investigation in which the separation of two (or more) minerals, heavier than TBE, was required.* *Among the cases studied in the IMI Laboratorles which fall into this category we can mention: alluvial deposits, such as heavy minerals in sea sand, tin deposits, or ground coarse-grained rocks, such as pegmatites. In such cases where, due to the petrographic structure, further fine grinding is required in order to achieve the liberation of the heavy components, the

Jan 1, 1964