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By Tell Ertl

THE Piceance Creek Basin in northwestern Colorado is believed to contain the richest large deposit of oil shale in North America. The major portion, about 1650 sq miles, is bounded by the White River on the north, the Grand Hogback, which runs from Meeker to Rifle, on the east, the Colorado River to the south, and the drainage basin of Salt and Douglas Creeks on the west. The Basin is a plateau 7000 to 9000 ft high, composed of 3000 ft of the Green River series of Eocene age and surrounded by a steep escarpment of 1000 to 3000 ft. From the escarpment the beds dip gently toward the center. Although oil shale is found in all members of the Green River series, the rich thick beds are found chiefly in the Parachute Creek member. This is normally capped by 100 to 200 ft of the Evacuation Creek, the youngest member of the Green River series. Actually the Piceance Creek Basin oil shale is not a shale, nor does it contain oil. It is magnesium marlstone holding solid organic matter capable of being broken down by heat into gases, some of which can be condensed into oil. The marlstone is resilient nonporous rock, difficult to sample by pick or hammer and moil. Many companies and individuals prospected the Colorado oil shale shortly after the first World War,' see Fig. 1, but because of the discovery of large quantities of petroleum in the late 1920's in Cali- fornia, Oklahoma, and East Texas, interest in oil shale development waned and did not revive until World War 11. In 1944 the writer, employed by the Bureau of Mines, prospected the high grade oil shale in numerous places along the southern outcrop of the Piceance Creek Basin. Several channel samples about 100 ft in length were cut, see Fig. 2. An eight-man crew needed a week to cut a satisfactory channel 80 ft long in the cliff face. The Phillips Petroleum Co., the Union Oil Co. of California and others also prospected the oil shale outcrop. In 1945 the Bureau of Mines initiated a core drilling program for the purpose of obtaining accurate samples from the Piceance Creek Basin. The U. S. Geological Survey set up a program for the geological study of the Basin that is still going on." Until the end of 1951 a total of 31 holes was drilled for core with diamond drills, and, in addition, cuttings through the oil shale have been obtained from 4 gas wells drilled by standard rotary oil well rigs. The Bureau of Mines drilled 12 of the holes, the Union Oil Company of California 8, the Standard Oil Company of California 6, the Sun Oil Company 3,

Jan 1, 1953

By P. V. Martin

SHORTLY after the middle of the nineteenth century, the invention of the regenerative open-hearth furnace and the development of the Bes-semer process stimulated a, rate of steel production whose magnitude created an unprecedented demand for pig iron. Revolutionary improvements in furnace design, auxiliary equipment, and operating technique enabled the blast furnace to keep abreast of the constantly increasing requirements of the steel mill. The development of improved blowing equipment, more adequate facilities for material handling, and particularly the general use of anthracite and coke to replace the physically weaker charcoal, led to a rapid expansion in both the height and volume of furnaces. Beyond a doubt,, however, the greatest single factor in blast-furnace improvement at this time was the use of the higher blast temperatures made available by the replacement of the recuperative iron pipe stoves by the regenerative Cowper brick stove. The increased blast tempera-ture not only resulted in greater output but also reduced fuel consumption far more than could be explained by the additional heat content of the blast. The progress of iron manufacturing was thus largely mechanical and thermal. Little attention was given tile chemistry of the process until the publication of the investigations of Sir Lowthian Bell.1 Bell's pains-taking experiments and investigations gave to the blast-furnace man his first real scientific conception of blast-furnace chemistry. Bell's recog-nition of the dual function of the carbon, the technical importance of reversible reactions and chemical equilibria, and his conception of the degree of oxidation of the carbon as shown by the analysis of the outgoing gases as a criterion of furnace efficiency, laid the foundation upon which has since been erected the structure of blast-furnace theory.

Jan 1, 1939

By Tell Ertl

THE Piceance Creek Basin in northwestern Colorado is believed to contain the richest large deposit of oil shale in North America. The major portion, about 1650 sq miles, is bounded by the White River on the north, the Grand Hogback, which runs from Meeker to Rifle, on the east, the Colorado River to the south, and the drainage basin of Salt and Douglas Creeks on the west. The Basin is a plateau 7000 to 9000 ft high, composed of 3000 ft of the Green River series of Eocene age and surrounded by a steep escarpment of 1000 to 3000 ft. From the escarpment the beds dip gently toward the center. Although oil shale is found in all members of the Green River series, the rich thick beds are found chiefly in the Parachute Creek member. This is normally capped by 100 to 200 ft of the Evacuation Creek, the youngest member of the Green River series. Actually the Piceance Creek Basin oil shale is not a shale, nor does it contain oil. It is magnesium marlstone holding solid organic matter capable of being broken down by heat into gases, some of which can be condensed into oil. The marlstone is resilient nonporous rock, difficult to sample by pick or hammer and moil. Many companies and individuals prospected the Colorado oil shale shortly after the first World War,' see Fig. 1, but because of the discovery of large quantities of petroleum in the late 1920's in Cali- fornia, Oklahoma, and East Texas, interest in oil shale development waned and did not revive until World War 11. In 1944 the writer, employed by the Bureau of Mines, prospected the high grade oil shale in numerous places along the southern outcrop of the Piceance Creek Basin. Several channel samples about 100 ft in length were cut, see Fig. 2. An eight-man crew needed a week to cut a satisfactory channel 80 ft long in the cliff face. The Phillips Petroleum Co., the Union Oil Co. of California and others also prospected the oil shale outcrop. In 1945 the Bureau of Mines initiated a core drilling program for the purpose of obtaining accurate samples from the Piceance Creek Basin. The U. S. Geological Survey set up a program for the geological study of the Basin that is still going on." Until the end of 1951 a total of 31 holes was drilled for core with diamond drills, and, in addition, cuttings through the oil shale have been obtained from 4 gas wells drilled by standard rotary oil well rigs. The Bureau of Mines drilled 12 of the holes, the Union Oil Company of California 8, the Standard Oil Company of California 6, the Sun Oil Company 3,

Jan 1, 1953

By B. G. Klugh

The present paper represents a preliminary investigation of the ultimate structure of iron-bearing materials which have been subjected to heat treatment for the purpose of agglomerating the fines, or for chemical changes, or for both. Primarily, the object of this inquiry was to determine the relation of the microstructure of each of these materials to its specific susceptibility to the action in the blast-furnace. It is hoped that this small contribution will serve as a nucleus to a line of research that will throw some light upon the debated questions involved in blast-roasting. Thus far the investigation has been conducted along lines of analogy of known principles, rather than through the application of any well-defined system of microscopic petrography. This is obviously due to the fact that we are dealing with ma-terials which are the artificial products of a new art, rather than with the natural materials from which the essence of the pure science has been evolved. In the limited time allowed for this research, it has been conducted upon those materials the chemical content of which allows of their use commercially in the blast-furnace. The following microphotographs are arranged in the order of the degree of complete fusion to which the mass in question has been subjected, in effectively binding the particles together. A very notable fact here clearly demonstrated is that the degree of fusion to which the material has been subjected is inversely proportional to the reducibility of the product. The characteristic of the material under consideration to which reducibility is almost universally attributed call be progressively traced in the following arrangement, through the identity of the obvious microscopic constituent. Furthermore, the degree of fusion to which a bod? has been subjected is recorded in the presence of resultant products of fusion in that body. Such readjustment is generally apparent

Jan 1, 1914

By T. H. Oxnam

INTRODUCTION. THE predominating value of the ores now being treated by the Palmarejo and Mexican Gold Fields, Ltd., is silver, although some gold is also carried. The present method of treatment consists of wet-crushing and concentrating, followed by the cyanidation of the unroasted sands and slimes. The sands are treated by leaching and the so-called accumulated slimes by a system of agitation and decantation. It is only within very recent years that the cyanidation of unroasted silver-ores has been commercially successful. In fact, at the time operations were begun at the cyanide-plant at Chinipas, February, 1902, I knew of no other leaching-plant treating similar ores successfully. The cyanide treatment of the Palmarejo ores differs but little from the ordinary practice in cyaniding gold-ores; and perhaps but little, if any, new information concerning the metallurgy of silver is to be gleaned from it. PALMAREJO MINE. The Palmarejo mines are located in the southwestern part of the State of Chihuahua, Mexico, on the foothills of the Sierra Madre mountains, at an elevation of 3,200 feet. The mills, 12. miles distant, are situated on the Chinipas river, near the town of Chinipas, which is about 150 miles northeast of Agiabampo, on the Gulf of California. Supplies are shipped via this port as this route is the best and most direct to the property. The ore-bodies in the Palmarejo mines have been deposited. along a series of rock-fractures, caused by an intrusion of eruptive rock. The most important of these fractures or fissures, both in width and value, are the Prieta and Blanca veins, which.

Jul 1, 1905

By C. L. Clark, J. Russ

FOR many years attempts have been made to develop a laboratory test that would serve to indicate the proper temperatures to be used in the various hot-working applications to which metals may be subjected as they are being processed from the cast ingot to the desired finished products. That these attempts have not been very successful is indicated by the fact that most of the temperatures in use today in these operations have been developed over a period of years by trial and error. In other words, the selection of the proper temperatures for the hot-working of metals is generally an art rather than a science. Our knowledge with respect to the behavior of metals at elevated temperatures has been greatly extended during the past several years. While most of the work in this field has been done at proposed operating temperatures of equipment, rather than at processing or fabricating temperatures, one outstanding fact has been developed, which is applicable to the entire high-temperature range; that is, that the rate of deformation to which the metal is subjected is of the same order of importance as the temperature. The failure to properly recognize this fact has greatly retarded the development of a suitable laboratory test for determining hot-working temperatures. INFLUENCE OF RATE OF DEFORMATION ON HIGH-TEMPERATURE PROPERTIES It is not the intent of this paper to survey all the work that has been done on the effect of deformation rate on the properties of metals. The importance of this factor, however, was shown by Zay Jeffries1 as early as 1919, when he called attention to the existence of the so-called equicohesive temperature and to the effect of certain factors on the location of this temperature. Fig. I is a diagrammatic sketch showing the effect of temperature on the relative strength of the crystals and grain boundaries and the type of fracture that will result, depending on the location of the test, or working temperature with respect to the equicohesive temperature. Since the type fracture varies, it also follows that at temperatures below the equicohesive temperature the major deformation occurs in the grains; while at temperatures above, the deformation results either from the movement of the grains with respect to each other or recrystallization of the strained material occurs almost instantaneously, producing new crystals at the fracture. As previously indicated, it is an established fact that the position of this equicohesive temperature for any given metal is dependent on the deformation rate. For example, in 0.15 per cent plain carbon steel the location of this temperature under

Jan 1, 1945

Discussion of the paper of CHESTER W. WASHBURNE, presented at the New York meeting, February, 1915, and printed in Bulletin No. 9S, February, 1915, pp. 469 to 471. ROSWELL H. JOHNSON, Pittsburgh, Pa.-I hope that this contribution of Mr. Washburne's is only the first of a series dealing more in detail with the very important problems involved. Pores are of two kinds: Those which are entirely inclosed, so that they do not belong to a system of communicating pores tapped by the bore hole or shot hole; second, those which do so communicate. Porosity, of course, includes both. But since pores of the first class are valueless to us, we should confine our attention to the latter, for which I propose the term "effective porosity." This should be measured by the Wisconsin method, based on the quantity of fluid that can be introduced by the aid of vacuum. Another factor which requires attention in this connection is the dependence of the extractability upon the rate of loss of pressure, as affected by the number of holes, and the rapidity of their completion, the existence of uncontrolled wells, the use by other operators of vacuum pumps upon the casing head, the exhaustion of a gas field in the same reservoir prior to the discovery of the oil, etc. The extractability depends upon the pressure available for the exclusion of the oil from the reservoir into the hole. The action of gravity in bringing oil into the hole is relatively small where the pores are very small, as is so frequently the case.

Jan 5, 1915

By John Furness Park

The mining district is located in the northeasterly part of Nevada, between the Jarbidge River on the west and the East Fork of the Jarbidge on the east. The northern boundary of the district is but a few miles south of the Idaho state line—the gold-bearing area extending from this point south, for 5 or 6 miles. • The Jarbidge Mountains, in which the ore deposits occur, range from 5000 to 11,000 ft. in elevation, the most important mines being situated about 7000 ft. or higher. The town of Jarbidge lies along the Jarbidge River and is reached by stage from Rogerson, Ida., the nearest railroad point. During the summer months, the camp may be entered from the south by way of Deeth, Nev., but no regular transportation facilities are available over this route. History The mineral deposits were not discovered until 1909, when D. A. Bourne, panning along the river bank, found gold in. the gravel at the mouth of a small stream flowing into the Jarbidge. He prospected in the vicinity of this stream, later known as Bourne Gulch, and shortly after located the North Star claims. During the following spring and summer (1910), the camp of Jarbidge grew from nothing to a town of 2000 people and the hills surrounding it were practically all taken up by mining claims. Most of the work done during the first year or two consisted of trenching and open-cut prospecting. Tunneling was started on a number of claims and many veins were uncovered. Mills were built and operated on a few properties, notably the Pavlak and the North Star. These ran only a few months, however, when they were closed down because of extraction and financial difficulties. A period of development followed in which the majority of the present producing mines were opened. The Elkoro Mines Co. acquired a number of claims in 1915 and started work on the present mill in 1917. Since that time other properties have been taken over until this company is by far the largest operator in the district. Only one other company is now actively engaged in mining, the Bluster Mining & Milling Co., which has

Jan 1, 1925

By E. L. Ickes

DURing the summer and winter of 1918 eleven standard rigs were erected in the United Kingdom to test the petroleum prospects of- ten structures, eight of which were in England and two in Scotland. By the fall of 1921 ten of the wells were completed; the remaining one, the D'Arcy in Scotland, was stopped some months later. The tests were deep ones, five of the wells being 4000 ft. or more, the rest varying in depth between 1810 and 3918 ft. The total footage drilled was 40,047 ft. The holes were put down with standard or cable tools purchased in the United States (except the boilers). The larger sizes of casing, 10-in. and above, were also from America, while the smaller sizes were secured in Scotland. The Hardstoft well in England found a small production of high-grade oil and the D'Arcy well also encountered what is reported as a favorable showing at a depth of 1810 ft. The Werrington and West Calder wells had to be abandoned on account of drilling difficulties. The Apedale well encountered great thicknesses of ash in the Carboniferous and had to be abandoned on account of depth. The results might be summarized by saying that of the ten structures drilled upon, two yielded encouraging showings; three cannot be considered as having been adequately tested; and five produced dry holes, although in some of these small oil showings and gas were met. The total cost of the work amounted to about half a million pounds sterling, which sum includes the cost of all equipment, subsequently sold by the government. The work, under the superintendence of V. L. Conaghan, took place for the most part in the period immediately following the war—a period of high prices, labor and transportation difficulties, and unsettled conditions generally; factors tending to retard the work and affect the costs. The writer, as a member of the staff of S. Pearson & Son, Ltd., had charge of the administration of the work during its later stages and

Jan 1, 1924

By Harry H. Angst, Reuel A. Cochrane

THE successful exploitation by opencut methods of the low-grade porphyry copper deposits is due to the economical handling of large tonnages. Large tonnages are possible only if the rock material is broken so that the large power shovels can operate with minimum delays. This is particularly true at the New Cornelia mine, where the dense, hard, tough rock material creates problems not encountered in most of the porphyry copper mines. The introduction of churn drills at the New Cornelia for primary drilling, in 1936, necessitated a complete change in the methods of breaking ground as formerly air drills had been used. The blasting operations are of particular interest because of the handling of great quantities of high explosives in safely and efficiently fragmenting the hard rock material. ROCK FORMATIONS At the New Cornelia mine the rocks are quartz monzonite with a diorite border facies intruding a rhyolitic series. Overlying these formations is a fanglomerate formation composed of boulders of monzonite, diorite, rhyolite, and other types of rock of unknown derivation. (The word "fanglomerate" is used in this paper in referring to the local conglomerate type of rock formations.) The ore body is approximately 4800 ft. long and 2800 ft. wide, and is of the disseminated type. Mineralization occurs principally the quartz monzonite and to some extent in the adjacent diorite and rhyolite. The principal ore minerals are chalcopyrite, bornite, and a small amount of chalcocite. Over a considerable area the quartz monzonite is extremely hard and siliceous in character, owing to pegmatitic zones of alteration. The hardness of the ground depends on the intensity of the silicification. In a small area in-the pit, the monzonite contains an abundance of pyrite accompanied by sericitization and is soft and easily fragmented. This is true also in the remaining oxidized portion of the ore body. The diorite and rhyolite formations, like the monzonite, vary from extremely hard to very soft material, but on the whole are easier to fragment than the monzonite. jointing is prevalent in all the rock formations and plays an important role in the blasting efficiencies. In the fanglomerate formation, numerous well-defined joints, widely spaced, tend to make the ground blocky when blasted. This is a deterrent to good fragmentation. In the other rocks the joints are more numerous and are closely spaced, except in localized areas where the formations are extremely hard. These descriptions indicate that the lowest blasting efficiency will be obtained in the harder formations, from which the major portion of the mine production is obtained; namely, the monzonite and rhyolite. All rock formations mined at the New Cornelia pit are so hard that excavation

Jan 1, 1941

The following paragraphs have been extracted from a recent publication of the U. S. Department of Commerce; Miscellaneous Series, No. 65, " German Trade' and the War, " which portrays the industrial, commercial and economic conditions of Germany, at the present time, and has been compiled largely from sources published in Germany. Iron and Steel The Krupp company, the greatest of the German munition works, was faced at the outbreak of the War with the disappearance of its great international business, but this was amply compensated by orders from Germany and her allies, and the activity of the company has been greatly extended. The general meeting of December 1914, voted an increase in the capital to 250,000,000 marks. The gross profits of the company, amounting to 61,900,000 marks in 1912-13, have been more than doubled during the war. The gross profits were 128,260,000 marks in 1914-15 and 143,360,000 in 1915-16. Large sums have been written off; 10,000,000 marks have been placed in the pension fund during the war, and 5,000,000 were appropriated for workmen's dwellings in 1915. Thirteen million marks have been devoted to war assistance in the last three years. The assets of the company were valued at 967,000,000 marks at the end of 1916. For the year 1916-17, the company paid a dividend of only 10 per cent., but set aside 85,425,000 marks for depreciation. The Bismarckhütte in Upper Silesia, capitalized at 16,000,000 marks, with a bonded indebtedness of 7,907,500 marks in 1913-14, reported 3,912,000 marks of net revenue from operation for that year. During the three years of war the revenue increased successively to 8,077,000, 11,805,000, and 16,994,000 marks. While the capital remained unchanged, and the bonded indebtedness was but slightly reduced, the dividends paid during the last four years were increased from 9 per cent. in 1913-14 to 15, 25, and 30 per cent. during the war. During the year 1916-17 the amount written off, chiefly on the works and plant account, was 10,553,000 marks, or nearly as much as the total set aside during the three preceding years. The turnover for that year reached a sum many times the amount of the capital. At the end of 1916 the company's shares were quoted at 275, as against 144 at the end of 1913.

Jan 8, 1918

By Milton E. Wadsworth, John N. Ong, W. Martin Fassell

The temperature and oxygen concentration dependence on the reaction of sphalerite in oxygen at pressures from 6 to 640 mm Hg have been investigated in the temperature range 700° to 870°C. Sphalerite has been found to oxidize linearly over this entire temperature and pressure range. At higher rates, considerable self-heating was observed. The dependence of the oxidation rate on the oxygen concentration may be expressed by: Rate = k' where k' is the specific rate constant and 0 = K1[O2]/(1 + KI[O2]), where K1 is the equilibrium rate constant for the adsorption of oxygen on sphalerite. Values of the activation energy and the enthalpy of adsorption were found to be 60.3 and —59.6 kcal per mol, respectively. Data have been presented that indicate conditions under which either a sulphatizing or an oxidizing roast may be obtained. ROASTING processes have been employed in the metallurgy of a great number of basic metals in use today. Until recently, however, little attempt has been made to deduce the fundamental mechanism by which oxidation takes place. Structural changes upon oxidation have been investigated1 = and thorough work has been performed with regard to the reaction products and the thermodynamics of the oxidation reactions. The objective of this investigation was to determine the rate of oxidation of sphalerite and to apply the absolute reaction rate theory in the theoretilcal interpretation of the experimental results." "O Description of Apparatus The apparatus contains the following features: 1—a furnace with gas system, 2—an autographic weighing system, and 3—a temperature control system. Furnace With Gas System—The furnace was mounted by a yoke on each end and was free to travel up and down on steel guide rods, permitting the introduction and removal of samples from the apparatus with minimum difficulty. The furnace was heated by three sections of Kanthal wire wound externally on a zirconia tube and insulated with Fiber-frax. Pure gases or mixtures of gases were introduced into the lower end of the furnace through two flowmeters, a mixing chamber, and a gas-tight sparger, Fig. 1. The gaseous products of the reaction and the unused gases were prevented from escaping to the atmosphere by maintaining a small negative pressure on the system. This procedure permitted air from the outside to enter through the small an-nulus around the quartz suspension fiber and prevented the escape of the internal gases. Autographic Weighing System—The autographic weighing system consisted of an adapted gold balance, a photoelectric circuit, and a weight recorder, Fig. 2. The sample was suspended from one end of the balance beam by means of a platinum chain outside the furnace and a long thin quartz fiber on the inside of the furnace. On the other end of the balance beam, the necessary weights were added to counterbalance the sample. In addition, a calibrated chain was added to the balance which was linked directly to the weight recording unit. Control was effected by means of a photoelectric circuit." A parallel beam of light from a strong source was directed onto a small front-surfaced aluminum mirror mounted in the middle of the balance beam and then to a front-surfaced mirror mounted on the ceiling of the room. The beam was then reflected onto a front-surfaced right prism at a distance of 9 ft from the balance

Jan 1, 1957

By Albert F. J. Bordeaux

(Cleveland Meeting, October, 1912.) THE immediate vicinity of the sea-shore, affording special facility for the exportation of ores, makes it possible to work certain mines in the Vladivostok district, which, in more remote places of Siberia, would remain unproductive. Outside of the city of Vladivostok the population is small and the country is very little prospected. Additional discoveries of valuable deposits like the large body of calamine which has recently been opened in the neighborhood of earlier worked lead-silver ores, in the Tetiuhe valley, are still in the field of possibilities. For many years gold alone was produced, in part from the coastal rivers and in part from a quartz-vein on Askold island near Vladivostok. But the production is diminishing, and prospectors are looking for other rivers in the interior, such as the tributaries of the Ussuri. These rivers are now more accessible than formerly, due to the slow but gradual development, of colonization by the Russian peasants. The few natives of the country, called Orodjones, are of the Chinese race. They resemble the North American Indian and are hardy fur-hunters. They have given some attention to placers and have already shown good specimens of gold-dust from the rivers Iman, Bikin, Noto, etc. Coal-mining was begun in the Vladivostok region more than 20 years ago, but in a somewhat irregular way. The industry is not as yet important and the best coal-seams are badly prospected, or ire even neglected. Copper, lead, and iron exist in several places. The amounts give some encouragement to the anticipation that the discoveries will give rise to important metallurgical works. I here present a review of the various deposits, based upon such safe information as is in hand, when I have not drawn upon my personal observations. Fig. 1 is a snap of Eastern Siberia, showing the mineral deposits.

Oct 1, 1912

By O. J. Hassel, W. T. Maidens, J. H. Calbeck

The rotary gas fired reheating furnace used by the American Zinc Oxide Co. at Columbus, Ohio for Therotarygasfiredreheatingfurnacerefining lead-free zinc oxide is described. The outstanding features of this operation are that the color of the zinc oxide is greatly improved, sulphur is eliminated, and cadmium arethatrecovered without densifying the product to an objectionable degree. IN 1919 Leland S. Wemple obtained a patent for a process of reheating zinc oxide wherein the "coarsening of grain due to excessive heating was avoided." He taught in his specification that if solid carbonaceous material, such as lamp black, was added to the zinc oxide in proper amounts prior to reheating, objectionable sulphur compounds could be removed and the color would accordingly be improved and no objectionable densification would occur because of the relatively low temperature required. The situation that made this invention imperative was the newly opened zinc oxide plant of the American Zinc, Lead & Smelting Co. in Hills-boro, Ill. This was one of the early Western Type American Process zinc oxide operations. Characteristic of all of these early Western operations using Tri-State and Western ores was the great difficulty encountered in obtaining a product low enough in sulphur to compete with the Eastern Type American Process zinc oxides which were made from ores containing very low sulphur percentages. Wemple demonstrated that the refining process of his invention produced a superior color and although this was true and a most welcome feature, the primary purpose of the early refining operations at Hillsboro was to reduce substantially the high sulphur content of the crude zinc oxide. Although many and varied attempts had been made for refining zinc oxide none of the processes had a commercial history of any consequence until Wemple's invention became standard practice for the American Zinc, Lead & Smelting Co. in 1919 and their operations have been unique in that substantially all of their lead-free zinc oxide has been reheated since the first installation at Hillsboro. This process has become known in the industry as refining. The furnace developed by Wemple and continued in use by the company from 1919 until 1943 was unusual and merits some consideration by way of review in this paper. The furnace was essentially a double hearth coal-fired muffle furnace with a mechanical raking system consisting of a central shaft supporting six rabble arms in each muffle. The untreated or "crude" zinc oxide was fed onto the outer rim of the top muffle, moved to the center where it dropped to the lower muffle and progressed to the outer rim where it was discharged into an alloy screw conveyor. The retention in this furnace was extremely short, about 5 min, and the shallow zinc oxide bed on the hearths of the muffles was being continuously turned by the fast moving rabbles. Soft coal was burned on the grates below the lower muffle and the long yellow flame necessary to carry the heat around both muffles resulted in a very inefficient combustion of the fuel. The temperature of the top of the lower muffle seldom exceeded 65 °C although the oxide itself often reached 700°C before discharge. The capacity of this furnace was approximately 1/2 ton per hr. In our plant at Columbus it was necessary to keep four of these furnaces running in parallel to take care of the production because, as mentioned above, every pound of zinc oxide produced during these 24 yr passed through one of these refining furnaces. An essential part of this refining operation was the use of carbonaceous material admixed with the zinc oxide fed to the furnaces. Between 1 and 2 pct of a bran produced in the processing of cotton seed was added to all zinc oxide charged to the furnaces. The bran ignited on the top hearth and was still burning when the charge fell from the top hearth to the bottom hearth making a cascade of sparks. The rapid turning of the zinc oxide caused these particles of bran to flash on the hearths behind each rabble; but the combustion, of necessity, had to be complete by the time the charge reached the outer rim of the bottom hearth, otherwise the finished product would be contaminated with the charred particles of bran which would give the zinc oxide an unsatisfactory color. Although this operation was initiated to reduce objectionable sulphur percentages, as time went on new properties of the product were appreciated which made advisable continuing the refining process long after other methods of sulphur reduction became known in the industry. The particle size and particle size distribution, the absence of colloidal fines and perhaps a unique surface condition gave this product an outstanding performance when used in paints. The Wemple furnaces installed in Columbus in 1919 had to be rebuilt frequently and were extravagant in the use of fuel. The raking mechanism and the muffles required excessive maintenance expense and as the furnaces wore out the problem arose whether to continue along this line or to explore the possibilities of obtaining similar or better results in the simpler and more commonly used rotary furnace. To this end special research was initiated in 1941 on a small laboratory rotary

Jan 1, 1951

By John C. Branner

No precise geographic limits can be given for the zinc- and lead-region of North Arkansas. In general terms it lies N. of the Boston mountains and W. of the St. Louis, Iron Mountain and Southern railway; but the prospecting and the development of the ore-deposits have not gone far enough to outline more than vaguely the areas over which workable deposits are to be expected. The tardiness of the development of the region is due in part to its topography, as a hilly and partly mountainous country, through which there have been no railways until recently. There is no longer any doubt, however, about the existence in that region of large bodies of zinc-ores. I. General Geology. The general geology of the region is, in the main, quite simple, but that of the ore-deposits is less so. The zinc-regions of North Arkansas lie about the southern flanks of the Ozark dome. The rocks are approximately horizontal, but have a gentle southward dip away from the axis of this dome. Figs. 1, 2 and 3 show the broad features of the to-. pography and geologic structure. South of the zinc-region, the sandstones and shales of the lower Coal-Measures form the north-facing escarpment of the Boston mountains. Beneath the Coal-Measure rocks are the limestones and cherts of the Lower Carboniferous; and these rest upon Silurian and Ordovician beds. The uppermost beds (Coal-Measures) have been cut into by erosion along the mountain-slopes so that their edges or outcrops have a meandering or dendritic form. The same thing happens with the Lower Carboniferous beds; but these, haying been more or less protected by the overlying Coal-Measured, have broader bases, and cover a much larger area. In places,

Jan 1, 1902

By H. C. Rogers

A phenomenological study of the failure of polycry stalline ductile metals at room temperature was carried out using light and electron microscopy. Tensile fractures as well as sections of partially fractured bars of OFHC copper in particular were examined. The initiation and growth of the central crack in the neck of a tensile specimen occurs by void formation. After the formation of the central crack the f'racture may be completed in either of two ways: by further void formation or by an "allernating slip" mechanism. The first leads to a "cup-cone" failure; the second, to a "double-cup" failure. In the past decade or decade and a half there has been a great deal of emphasis on the solution of the problem of the brittle fracture of metals, particularly those which normally exhibit considerable ductility such as steel. Since the problem of the fracture of metals after large plastic strains has less immediate commercial or defense significance, there has been considerably less effort expended in describing the details of the phenomenology and determining the mechanism of this type of fracture. The present research was undertaken to increase our knowledge in this area. The problem of ductile fracture has not been neglected completely, however. Ludwik1 first found by sectioning a necked but unbroken tensile specimen of aluminum that fracture began with a large internal crack which appeared to have started in the center of the neck. Examination of the fracture indicated that the crack had propagated radially with increasing deformation until a point was reached at which the path of the fracture suddenly left this transverse plane and proceeded at approximately 45 deg to the stress axis until the surface was reached. This gives rise to the commonly observed cup-cone tensile fracture. When MacGregor2 was attempting to demonstrate the linearity of the true stress-true strain curve from necking until fracture, he found that copper was anomalous in that the stress dropped off markedly from the straight line value before fracture occurred. Radiography indicated that in the copper an internal crack was formed long before the final fracture, the stress decreasing during the growth of this crack. One of the most significant advances in the understanding of ductile fracture was the result of work by Parker, Flanigan, and Davis.3 By the use of etch-pit orientations they were able to demonstrate conclusively that the fracture surface at the bottom of the cup, although on a gross scale normal to the tensile axis, did not consist of cleavage facets as had been previously supposed by many investigators. Recently, Forscher4 has shown evidence of porosity near the tensile fracture of hydrogenated zirconium which he attributes to hydride decomposition. The workers at the Titanium Metallurgical Laboratory5 have also shown evidence of porosity in a number of the commonly used metals after heavy deformation. Many metals have relatively low ductility during creep tests at high temperature. The fractures are intercrystalline, resulting from the nucleation and growth of grain boundary voids. The work in this area has been recently reviewed by Davies and Dennison.6 It is possible that some of the observations and conclusions may have a bearing on the present study? especially since at least two studies7,' have been extended down to room temperature and below using magnesium alloys. However, since magnesium does exhibit low-temperature cleavage, these results may not be pertinent to the present one. The use of the electron microscope as an aid to the study of fractures has been extensively exploited by Crussard and coworkers.9 The examination of direct carbon replicas of the fractures of a large number of metals and alloys showed that the bulk of the fracture surface was covered with cup-like indentations of the order of 1 to 2 µ in size. These frequently had a directionality by which Crussard claims to be able to tell the direction of the crack propagation. With this rather disconnected background of information, this investigation was undertaken in the hope of presenting a unified picture of the initiation and propagation of a fracture in a ductile metal. To this end all of the techniques previously used were employed simultaneously so that there might be a good correlation of the data obtained by different techniques. EXPERIMENTAL PROCEDURE The metal which was chosen as the starting material for this investigation was OFHC copper. Of the dozen or so materials considered, it best fulfilled the requirements of commercial availability in large sizes, good ductility, relatively high melting point compared with room temperature and

Jan 1, 1961

The early history of a country is linked with its topographic features. Mountains are barriers, rivers are avenues, the sea is a highway. The first Europeans to reach the northwestern corner of the American continent, now known as Alaska, came from Asia, for the Pacific Ocean provided an approach by means of the islands that like stepping-stones stretch far westward from the inhospitable shore of the mainland. The Russians crossed Siberia and explored the Arctic coast of Asia. In 1728 a band of Cossacks was driven by a storm eastward from Kamchatka, and landed in Norton Sound.* Others followed them, and settled on the islands and peninsulas of southeastern Alaska. The mountains guarding the coast discouraged any advance into the interior. Another range, the northern extension of the Rocky Mountains, barred the westward progress of the French voyageurs and the English fur-traders of the Hudson's Bay Company. After the Russians had obtained a foothold among the Indians, the viceroys of Mexico sent successive expeditions up the coast, such as that of Pérez in 1774 and of Heceta in 1775. If the English fur-traders had not interfered, the Spanish and Russian spheres of influence would have conflicted, and the contest for control might have ended in establishing a line of demarkation somewhere near the mouth of the Columbia river. The British navigator Captain James Cook landed near Sitka in 1778 while seeking a way by water to Hudson Bay. Fifteen years later his midshipman, George Vancouver, in command of another British expedition, surveyed the coast

Jan 1, 1932

By T. Sterry Hunt

I HAVE in a previous communication called the attention of the Institute to the geognostical relations of the crystalline iron ores belonging to the Eozoic rocks of North America, at which time I noticed (1) those associated with the gneisses of the Laurentian series, (2) those of the crystalline schists of the Huronian, as seen in Northern Michigan and in many localities along the Appalachians ; (3) those of Southeastern Missouri associated with petrosilex porphyries and schistose rocks, and presumed to be nearly of the same age with those of the Huronian schists; and (4) the highly titaniferous ores of the Norian or Labradorian series from Essex County, N. Y., and from various parts of Canada. It may here be remarked that, although the presence of titanium is most marked in the Norian ores, this objectionable element is sometimes found in the schistose ores of the Huronian, and to a lesser extent in certain Laurentian magnetites. The ores of each of these geological divisions have their individual peculiarities, which serve to distinguish them to such a degree that the magnetites and specular ores of the Laurentian are as dissimilar to those of the Huronian as are the crystalline silicated rocks of the two series. As it happens that these mineralogical dissimilarities correspond to differences in composition and in adaptability to different processes of manufacture, which, in the present condition of the iron industry, are objects of special consideration to metallurgists, it will be seen that these geognostical distinctions become of great practical importance. During the past year I was desired by the Geological Commissioners of Pennsylvania to devote a few weeks to certain geological studies in the eastern part of the State, in the course of which I was enabled to make, with regard to its crystalline iron ores, some observations to which I desire to call the attention of the Institute. I may mention, in passing, that the great South Mountain belt, from the Schuylkill to the Delaware, is composed of Laurentian rocks, in which are found the characteristic ores of the series like those of the Highlands of New Jersey and New York, and of the Adiron-

Jan 1, 1876

By Max W. Ball

An intelligent discussion of the oil situation and its needs, whether from the standpoint of the prospector, the operator, the engineer, or the public administrative officer, must be founded upon a knowledge of the law under which oil lands are obtained. A consideration of new legislation must be prefaced by an understanding of the present law and its results. This paper undertakes to present no new remedy for the ills of the present situation, no new solution of the problems the oil business is facing. It attempts merely to summarize the present law, its provisions, its origin, its development, and its effects. The discussion does not pretend to be exhaustive from a legal standpoint. It aims to avoid legal intricacies which tend to. confuse rather than clarify. It seeks but to present the essentials of the existing situation. The title to government lands known to contain valuable deposits of petroleum may be acquired only under the terms of the placer law as embodied in Section 2329 et seq. of the Revised Statutes. As a preliminary to considering the desirability of this situation it is profitable to examine into its origin. Origin of the Law Congress has left no room for doubt as to the legal applicability of the placer law to oil lands. The Act of Feb.11, 1897(29 Stat., 526), provides: "that any person authorized to enter lands under the mining laws of the United States may enter and obtain patent to land containing petroleum or other mineral oils, and chiefly valuable therefor, under the provisions of the laws relating to placer mineral claims.' . The immediate cause for the passage of this Act was stated in a brief report in the, House of Representatives (there was no debate in the Senate) to be a decision of the Department rendered Aug. 27, 1896 (Union Oil Co., 23 L. D., 223), directing the cancellation of an oil placer entry on the ground that land containing petroleum cannot be located and entered as a placer mine. The report of the Public Lands Committee of the House contains the following interesting statements Congressional Record, vol. xxix, p. 1409):

Jan 1, 1915

By William P. Blake

The Rainbow Lode is situated at Walkerville, in the Summit Valley mining district, Silver Bow County, Montana Territory, about one mile from Butte City. It was so named ill 1876 by Mr. J. E. Clayton, in recognition of the broadly-sweeping curve of the outcrop across the rounded surface of the eastern slope of a granitic mountain, at an elevation of about 6000 feet above the sea-level. It is on the western side of the range which divides the waters of the Missouri from those of the Columbia. History.—The history of the district is an instructive one. The water-courses and flanks of the hills were worked for years for placer gold. Millions of dollars' worth of low-grade gold have been washed out of the surface gravels below the veins of the district. Missoula Gulch and Silver Bow creek, just below Butte, are noted for their rich placers, and they continue to yield largely, producing within narrow limits from $50,000 to $100,000 dollars' worth of golddust yearly. It is ragged vein-gold, and evidently is near its parent source. It is no doubt derived from the disintegration of the veins of the district, and this conclusion was soon forced upon the miners. The veins which were seen outcropping boldly upon the slopes above them were located, and prospecting commenced. These outcrops were found heavily stained and blackened with oxide of manganese, and were porous and honey-combed in places, showing that the quartz was formerly filled with pyritous ores, and that these ores had decomposed and dissolved away, leaving, however, portions of the precious metal behind, especially at and near the surface of the ground. Assays of the croppings gave variable and often contradictory results; but the fact. that these were the outcrops of lodes bearing gold and silver in depth was patent to any experienced observer of mineral veins. The lodes of the district were first brought prominently to notice by Mr. Clayton in 1876, and in October of that year the Alice mine, upon the central portion of the lode, was opened by Mr. Marcus Daly, now so well known as the superintendent of the Anaconda Copper mine, upon another extremely interesting lode, in the same region.

Jan 1, 1888