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By Thomas S. Carnahan

The mining property of the Utah Copper Co. is situated in the West Mountain mining district, Salt Lake County;Utah, in the Oquirrh Range of mountains. Geology In a general way the rock formation of the district consists of a series of beds of quartzite and limestone intruded by a body of monzonite porphyry roughly elliptical in shape, with an east-west axis over a mile in length and a north-south axis of about 3,000 ft. This porphyry intrusion, accompanied by strong mineralizing action and fracturing, resulted in the formation of orebodies in the adjacent sedimentary rocks, and was itself sufficiently mineralized to make it one vast orebody. The Utah Copper Co.'s mining property comprises within its boundaries practically the entire outcrop of the monzonite mass, of a commercial grade. Genesis of Porphyry Ore Following an intricate system of fracturing, mineral solutions circulated freely through the porphyry, depositing small quantities of copper and iron, and resulting in a considerable silicification of the monzonite. The quantity of copper originally deposited was undoubtedly too small to have ever given the porphyry a commercial value, had not secondary enrichment, due to the leaching of the copper from the surface of the mass and re-deposition in the sulphide zone, been active over a long period of years. A large portion of the leached material has probably been removed by erosion, but there still remains a blanket of leached and oxidized porphyry of varying thickness covering the sulphide ore, known as capping. Over certain sections of the orebody, this capping contains commercial quantities of copper carbonates, but most of it contains little or no copper.

Jan 1, 1916

By N. P. Pinto

Compacting below the recrystallization temperature was studied. Ideal density was attained at 550° to 600°C using 25 tsi. Compacts have strength and hardness higher than cold worked beryllium. The recrystallization temperature of this highly stressed metal is that of cast, cold worked beryllium and appears independent of pressing temperature. THE process metallurgy of beryllium is beset by many difficulties that hinder the production of sound beryllium shapes of controlled properties. Most of these obstacles are traceable directly to the low density, low ductility, and high affinity for oxygen of the metal. Castings are susceptible to cracking and porosity, and controlled grain size is not easily attained, yet is critical to further working. Any process must carefully avoid oxygen pickup. Conventional metallurgical processes, including melting, casting, forging, rolling, and extruding have been treated previously,'" as have the conventional powder metallurgical methods.' More recently, a method has been advanced for producing powder compacts of high density by hot pressing at 1000" to 1100°C, using pressures of 0.25 to 0.5 tons per sq in. (tsi).3 Here, Seybolt and coworkers attained theoretical density of 1.85 grams per cc using pres-sure-temperature combinations of 500 psi-1100°C, 750 psi-1075"C, and higher. The warm pressing of beryllium is a practical method for producing bars of controlled properties and appears to have certain advantages, particularly when high strength and hardness are required. Other investigators have studied the hot pressing of various pure metals, such as copper,"-" gold," iron,10-11 and aluminum." Their results indicate that ideal densities may be attained by compacting at temperatures less than 50 pct of the absolute melt-

Jan 1, 1955

By E. S. Fisher

GRAIN coarsening implies a discontinuous type of grain growth during which a few grains in a fine grained recrystallized matrix grow to large grain sizes at the expense of the matrix. Studies of this phenomenon in various metals1,2 indicate that grain coarsening may result when continuous grain growth in a fine grained matrix is inhibited by either a dispersion of very fine inclusions or by a strong texture. In the former case a period of annealing time exists prior to grain coarsening during which grain growth inhibition is gradually de- creased by dissolution or coalescence of the dispersed inclusions. This mechanism can be made to occur in uranium during anneals at high a phase temperatures. ' A study of some of the factors influencing the kinetics of grain coarsening and the coarse grain sizes in a uranium has led to a method for preparing a uranium single crystals. Previously such single crystals containing considerable substructure were prepared at this laboratory by a phase change method, similar to that described by Cahn.3 Attempts to prepare more perfect single crystals by strain-anneal techniques were unsuccessful. Cahn3- as reported his attempts to apply such techniques to uranium. He proposed that the failure of strain-anneal techniques is basically due to the many twins which

Jan 1, 1958

By C. S. Corbett

EARLY in the development of every oil field, the operators of relatively large tracts of land must decide upon a spacing plan for the wells to be drilled upon their respective tracts. Usually it is desirable to have a system of regular spacing laid out over the entire tract, making such adjustments as may be necessary near land boundaries. Unless the dip of the producing formation is very steep, the equilateral triangular arrangement is the one most generally preferred, for the very good reason that it gives the maximum amount of drainage area for the wells up to the limit at which mutual drainage interference begins. Assuming that the equilateral triangular pattern is to be used, there still remains to he decided the matter of distance between wells. Many variable factors enter into the problem of proper spacing, some of which are physical and some economic. It is not the purpose of this paper to discuss these factors, as that has been done in several comprehensive articles during the past few years. In the end the decision must be based upon an estimate of the relative importance of various factors which apply to the field in question and to economic conditions in the oil industry at the time the development is getting under way. Even if the best possible spacing distance should be chosen when the problem arises, changing economic conditions and variation in physical conditions in different parts of the field may cause the original choice to become more or less unsatisfactory. Obviously, it is advantageous, once a spacing plan has been adopted, to avoid alteration of it as the field becomes better known or as conditions in the industry change, and yet be able to vary somewhat, the acreage per well in extending the area of development. Or, it may be desired to provide for an ultimate spacing considerably closer than conditions seem to warrant early in the development of the field. With these contingencies in mind, it is of interest to examine the possibilities which the equilateral triangular system affords. Orientation of Coordinate System In this system the well locations may be considered as the inersectionst of three sets of coordinate lines, the lines of each set intersecting those of the other two sets at 60. For convenience in placing such a system

Jan 1, 1930

By N. K. Chen, R. Maddin, R. B. Pond

A METHOD has been described by Andrade' for obtaining very rapid grain growth so that single crystals of high melting point metals could be made with comparative ease. The furnace construction was essentially a very thin wire through which was passed an electrical current so that "a high uniform temperature" was maintained. The wire was surrounded by a fused quartz tube from which the air had been evacuated. Andrade applied this method to the growth of single-crystal wires of alpha iron, and Tsien and Chow2 prepared single crystals of molybdenum 0.25 mm diam in this way. In the present report a method is described in which the basic idea of the Andrade furnace is utilized. However, modifications are employed so that large single crystals of molybdenum or of any refractory metals can be grown. Furnace The modified Andrade furnace is shown in Fig. 1, and the detailed drawing of its construction can be seen in Fig. 2. The furnace proper consists of a 2'/2-in. diam fused silica tube, 20 in. long, which is evacuated continuously at the bottom. Two water-cooled copper electrodes hold the specimen by means of collets held in place in the electrodes by set screws. These electrodes serve also to transmit power to the specimen. The lower electrodes can be clamped to the stand, while the upper electrode is fastened in place to the bellows which in turn is further connected to one side of the lever arm, flexibly supported at the top. After the specimen is mo;nted- and the vacuum is secured, the lever arm is adjusted by means of the counter weight so

Jan 1, 1952

By W. A. Thatcher

Nearly three years of experience in Spanish Honduras has placed the writer in possession of many facts concerning its resources which may be of interest to the Institute. According to the most trustworthy surveys, Honduras is bounded on the north and east by the Caribbean Sea; southeasterly by the river Segovia (or Wanks), which flows into the Caribbean at a point called Cabo Gracias a Dios (Cape Thanks be to God), long famous as the favorite hiding-place of the celebrated pirate, Morgan ; southwardly by a corner of San Salvador, the Bay of Fonseca, and the Republic of Nicaragua; Guatemala and San Salvador form tile western boundary. It is one of the five republics composing Central America, has a population of about 310,000 and an area of 150,000 square miles, lying between the 13th and 16th degrees of N. latitude, extending from north to south 200 miles, between the Atlantic and Pacific, and 400 miles from east to west, between Guatemala and Cape Gracias a Dios. It is composed of 13 States or Departments, under one common law. The principal resources are valuable woods, hides, rubber, tobacco, coffee, fruit, cattle, silver and gold. It is of the mineral resources of the country that I will speak, calling attention to the most noted mines, and their relative position to Tegucigalpa, the capital. The introduction of foreign capital into the country dates back about eleven years, and to-day there are at least twenty-five well organized companies.

Jan 1, 1892

By S. R. Elliott

The principles of the caving system, as they apply to mining soft iron-ore deposits, are well known, as this method has been in use for many years. It is, however, necessary to give a general description of it before describing the Athens method. The shaft and surface equipment should be placed at a sufficient distance from the orebody, so that the caving and pulling of the surface will not disturb the operations of the mine. Levels are started at the proper intervals, and when raises are completed, slicing commences at the top of the orebody and progresses downward. The necessary precautions are taken to avoid the occurrence of large open rooms and it is customary to break sufficient capping to form a mat to prevent heavy falls of ground from crushing through to the lower sublevels and endangering the lives of the workmen. Slicing is continued, and when sufficient width and length are undercut, the capping commences to cave, and in time a settlement occurs at the surface. As soon as this caving commences, the pressure on the timber increases; after it extends to the surface, the amount of pressure has a certain relation to the depth. In other words, the pressure increases with the depth, but not in direct proportion. At great depths, such as are found at the Athens, 2500 ft. (760 m.), the pressure might be so excessive that the cost of keeping working places open would be prohibitive. The actual caving of the surface in a deep mine, with a great thickness of capping, is slow and often takes years to accomplish. After sufficient width and depth have been undercut, the capping starts to break away, but, through arching, large masses of rock fill the opening, support the capping, and retard the continuation of caving. Caving to the surface is, therefore, retarded until either a sufficient thickness of the orebody is removed, or the width and length of the undercut part have been greatly increascd. I wish to emphasize this fact of slow caving, for it is on this principle that the success of the Athens system largely depends. Assuming that work is begun at the top, in this case at an elevation of about 1500 ft. (456 m.); that there is a thick bed of sand saturated with

Jan 1, 1922

By E. G. Leonardon

THE first to appreciate and foresee the value of applying electrical measurements to structural studies was Prof. Conrad Schlumberger, Professor of Physics at the School of Mines in Paris. One of his earliest practical undertakings in this line was carried out, in the field, at Fierville-la-Campagne, Normandy, in 1912. His book, published in 1920,1 still stands as an authoritative, fundamental treatise on the use of the electric current in geological studies, in spite of the rapid evolution of geophysics during the last seven years. A remarkable feature of this book is that, even then, it stressed the role of electricity in structural investigations and made public the first successful results obtained therewith. Stratigraphic studies have been pursued continuously by Conrad Schlumberger and his associates since 1912, the only interruption being the World War. The results attained demonstrate the wide possibilities of electrical exploration in structural work. This field of activity is, at the least, as varied and valuable as the search for ore. It is curious that until very recently it has so slightly attracted the attention of geophysicists and geologists on this continent. The purpose of this paper is to present briefly some examples of the practical application of the potential methods to geological studies. These examples are chosen from a number of problems solved in the field by our firm, in the course of its consulting practice. Certain fundamental points are briefly stated before the field operations and interpretations are described.

Jan 1, 1928

By W. L. Austin

The advance made in recent times in this branch of metallurgy is indicated by the attention the subject is receiving from important American copper-producing companies. Reference to the files of publications devoted to the mining industry discloses that some 20 American companies are actively investigating the amenability of their ore, or other material, to leaching methods, and that plants of varying capacities up to 10,000 tons per day arc under construction or are projected. Several leaching works are in commercial operation. It has been frequently pointed out that no method of leaching is universally applicable, for the reason that each ore differs in some particular from apparently similar ore found elsewhere, and also because local conditions are rarely the same even where the ore closely approximates in character that being worked at some other point. For this reason the older companies are approaching the matter in a conservative manner, experimentally determining for themselves the salient features in each instance. In considering a leaching proposition three factors at once fix the attention: (1) disengaging the metal from mineralized forms in which it is found in nature; (2) recovering the metal in a commercial state after it has been dissolved; (3) the apparatus best adapted to carrying out the several operations. Bringing the Metal into Solution This feature.has been found to present no serious difficulties. Numerous solvents for copper are known, and it has been repeatedly demonstrated on a commercial scale that from 80 to 90 per cent. of the metal contained in an ore can be rapidly brought into solution. It is interesting to note, however, that all of the companies above referred to have selected sulphuric acid as the basis for a lixiviant. Where oxidized ore practically free from precious metals is treated simple leaching with

Jan 1, 1915

By R. C. Palmer

THE testing of flotation oils has occupied a large part of the time of the testing departments of various companies using the flotation process in the beneficiation of their ores. The great differences in ores and iii oils has made such work necessary as it has not been possible to select the oil best suited for the purpose without trial of many kinds. In fact, individual shipments of flotation oils from the same manufacturer will often differ so radically that the mill men have been forced to test every lot of flotation oil before its use in the mills. Further, although almost every imaginable product of the distillation of wood, from alcohol to pitch, has been tested in a more or less perfunctory manner by various people, few companies have allowed the results of their tests to be made public. This work was undertaken for the purpose of obtaining reliable data regarding the value as flotation agents of a number of products that are obtained from the distillation of wood by different methods, and incidentally to determine whether some of the products not used at present could be used. Large quantities of such materials are being wasted or burned in the wood-distillation plants of the United States, and if some use other than fuel could be found for these materials, such a use would represent a distinct saving to the country as a whole, would increase the profit of wood-distilling plants now operating and perhaps make it possible for others to operate which at present cannot do so except at a loss. At the same time it was thought that if such products can be used as flotation agents, then their use would serve to increase the number of oils and other products available for flotation purposes. It was also hoped that it might be possible to discover a substitute for some of the most effective but comparatively high-priced oils which are now used for flotation

Jan 8, 1916

By T. M. Berry

FOR the past several years it has been growing practice to install circular shafts at deep mining operations. Several factors have brought this about. Throughout eastern and midwestern coal fields circular shafts have been conventional for many years. Where large bodies of coal are mined, a production shaft may have a life of 20 to 30 years. Quantity production is essential; therefore the shaft must have a large cross-sectional area for larger skips and cages. Mechanical mining has become a necessity if a company is to stay in business today. Continuous mining machines and cutting, loading, and hauling equipment must be taken in and out of the mines. If the access shaft is not large enough there will be expensive dismantling and assembling. This has become a problem at many operations, particularly in the western sections where ore was originally mucked by hand into small cars and hoisted by a skip through a narrow rectangular shaft having small compartments. Mechanical loaders must be dismantled to wheelbarrow size to go into these mines.

Jan 7, 1957

By G. S. Brooks

The tendency of the oxides of such metals as aluminum, zinc, chromium, and calcium to form compounds at high tempera tures with iron oxide is well established by past investigation. Data of this reaction, as developed in laboratory research, have been contributed by Burleigh, Hofman, and Wells, in America, and by many others abroad. A partial bibliography of the subject is appended. From these authorities we learn that the ferric oxide here has the function of an acid, giving in the case of ZnO a zinc ferrite, with a normal composition of ZnOFe2O3 This formation of zinc ferrite particularly affects the success of such processes as leaching or magnetic separation, and thus becomes practically important to the metallurgist. But the meager existing data do not entirely agree; and quantitative results from muffle-practice are conspicuously absent. Furthermore, it being of some general importance to the zinc smelter in both roasting and reduction, the following few notes of operations oil a commercial scale are contributed: I. Physical Properties of Zinc Ferrite. As formed for the most part synthetically by investigators, zinc ferrite exhibits characteristic physical properties, such as octahedral crystals, dark color, and a density over 5, together with a slight magnetic attractability. In examining with the microscope many products of mechanical muffle-roasting kilns, it is, however, impossible to find individual grains which can be identified as consisting entirely of zinc ferrite. The variety of colors, especially where each grain of blende was mechanically free from marcasite, rather conveys the impression of a partial ferritization of the grain. One side or end, for example, may often have the hard, dense surface and dark red to black color of the ferrite, while the balance shows the usual light yellowish brown of a normal iron-free blende.

Jan 1, 1914

By George I. Adams

Peru is divided into three regions—the coast, the ~ierra, or high mountainous region, and the " montaiia," or forest region of the Amazon basin. The Coast.—The coast is an arid region. No rain falls excepting in the extreme northern part, which borders the Gulf of Guayaquil. There is, however, a slight precipitation in the form of mist (gcirua), which occurs on the coast hills during the so-called winter months. The aridity of the coast is due principally to the antarctic, or Humboldt, ocean-current, which, being cold and having a temperature lower than that of the land, absorbs rather than produces vapors. The coast mists occur during the season when the land is relatively cold. N ear the Gulf of Guayaquil the antarctic current diverges from the coast, so that in the Tumbes valley and adjacent country the conditions in the summer months are such as prodnce rains. In the remaining valleys of the coast, agriculture is made possible only by means of irrigation, and is accordingly very limited in extent, although rich and varied. In the northern and south-central portions of the coast, plains extend inland from the sea, while in the southern part there is a coastal plain separated from the Pacific by a range of coast hills. Between the northern and south-central plains, as well as between the south-central and southern, the foothills of the sierra descend to the seacoast. The Sierra.—The sierra embraces the high land dominated by the lofty cordilleras of the Andes. In the southern part of Peru there are two cordilleras, the western and the eastern, which enter from Chile and Bolivia respectively, and inclose between them the Titicaca Lake basin. To the north of Lake Titicaca these cordilleras unite in the knot of Vilcanota, south of Cuzco. From this knot three cordilleras, known as the western, the central, and the eastern, extend to the northward, reuniting in the

Jan 1, 1909

By Robert H. Leach

SILVER the whitest of all metals, has been used for thousands of years. Students of antiquity agree that silver, gold, copper, and their alloys were the first metals discovered by man and they have all played an important part throughout the advance of civilization. Native silver has been found in different parts of the world in varying form and size, such as clusters of fine wires in rock cavities, thin sheets along cleavage planes in veins of rocks, and pieces of irregular shape that vary in size from extremely small particles to masses weighing many pounds. Nearly pure silver is found in, the native state but the native metal is more likely to contain copper or gold. Some of the natural alloys closely approximate the compositions of synthetic alloys that are used in the arts at the present time. As these native silver alloys usually are malleable and ductile, it is evident that prehistoric man was provided by nature with metals that he could work, with the crude tools at his command, into simple ornaments or other articles. The relative scarcity of silver combined with its resistance to attack under ordinary atmospheric conditions have been important factors in determining the purposes for which man has used it. Its scarcity and indestructible character have made its possession particularly desirable, and from the earliest times its principal use has been as a measure of wealth and a medium of exchange. The comparatively high value of silver in relation to other commodities makes it possible to transport a large amount of wealth in small bulk, and silver has traveled back and forth over all parts of the world. Even when made into ornamental pieces, such as bracelets,

Jan 1, 1953

By AIME AIME

FEW men are as well known to metallurgists or steel men everywhere as this year's Chairman of the Iron and Steel Division. This is evident from the writer's experience some years ago while visiting Krupp's new open-hearth plant near Essen and the Skoda Works at Pilsen. The first question asked there was: "You know Dr. Herty?" Knowing Charlie Herty has advantages, not the least of which is (or was in 1933) a fine lunch with a plethora of good Rhine \vine at Essen and a super- plethora of Pilsener beer at Slioda.

Jan 1, 1941

By Paul Weir

During the past decade, methods of producing bituminous coal in the state of Illinois, which ranks third in production among the states in which bituminous coal is mined, have undergone great changes. From less than one million tons in 1923, the strip-mine production has gradually increased to a high of 11,725,870 tons in 1937. From a negligible amount prior to 1927, the amount of coal mechanically loaded underground had increased to a high of 28,374,362 tons in 1937. The amount manually loaded in 1937 reached a low of 12,332,023 tons. In this same year, this state ranked first in strip-mine production, also in mechanically loaded production. For this reason a study of the influence of mechanization on location of production in Illinois may be helpful in anticipating what may happen in other producing states. The reason for the changes in methods lies in the differences in costs of production. The Bureau of Research and Statistics of the National Bituminous Coal Commission has made public the following costs of production by various methods in the state of Illinois (district 10) for the last nine months of 1937: all mines, $1.7602 per ton; strip mines, $1.4319; mechanical loading mines, $1.7457; hand loading mines, $2.1793; all underground mines, $1.8703. These are weighted averages for the entire district. Inasmuch as production in 1937 was reported from 58 counties scattered over two-thirds of the area of the state and from five different seams varying in thickness from less than 3 ft. to as much as 12 ft., it is apparent that the location of production must be influenced by the extent of mechanization possible in the various producing counties. SHIFT in Production The term "mechanization" is commonly used to designate the coal-loading operation. However, in a broader sense it embraces the use of any and all mechanical and electrical equipment on the surface and underground. Strip mining is an intensive form of mechanization. The mechanical cleaning of coal is a form of mechanization. Cutting machines and motor haulage likewise are forms of mechanization, hence

Jan 1, 1940

By H. T. Clark, H. K. Work

The instrument for the rapid determination of carbon in steel, described in this paper, was developed originally to facilitate the operation of the pilot-sized open-hearth furnace in the Jones & Laughlin Research and Eevelopment Laboratory. In this small furnace, with its shallow bath, the drop in carbon is accelerated, and a rapid, reliable test for carbon content is indispensable. This problem becomes rather acute when it is desired to finish heats at a carbon content higher than can be estimated with any degree of accuracy by the fracture test. Several independent methods for determining carbon were investigated, therefore, and it was found that a relatively simple magnetic device could be made to give reproducible results. A laboratory instrument was designed and set up for the use of the furnace operators. It was tested exhaustively in the laboratory and was used with considerable success for following the carbon content in the furnace bath. As soon as sufficient data had been compiled to indicate that the instrument might have a wider application, a more rugged model was constructed and placed in the mill to be tested on commercial heats. Finally, about a year ago, instruments were furnished to the plant open-hearth shops, and these have been in use since that time. As a matter of convenience, the instrument has been named the "Carbanalyzer," and will be referred to by this designation in the following pages. $ Eaklier Investigations While by far the greatest number of magnetic investigations in which the carbon content of ferromagnetic materials was considered have had to do with the evaluation of the magnetic properties of steels of known

Jan 1, 1940

By Allen D. Garrison

The chemistry of clays and shales has been assuming increasing importance in the petroleum industry, and two factors have greatly influenced this trend. The first has been the growing evidence that the marine shales are source beds, and that the petroleum compounds have migrated to the sand reservoirs overlying or underlying these shales: the second has been the demand for drilling fluids better adapted to penetrate these marine shales without difficulty and expense. Origin and General Composition of Clays and Shales Clays, shales and surface soils are all closely related materials. They are mixtures of finely divided compounds formed during the weathering of the solid crust of the earth. Their nature is essentially colloidal; that is, their behavior is determined by the state of division of the materials and the surface reactions of the smallest grains. Many of their chemical changes affect only the exposed areas and do not involve the interior of the grains of matter. The extent of these reactions is more nearly proportional to the area of the substances than to their mass, therefore it is possible for a small amount of a material in an extremely fine state of division to completely dominate the character of the mixture. More than 83 per cent of the crust of the earth is composed of three elements—oxygen, silicon and aluminum. Consequently, the corrosion products of the crust are predominantly aluminosilicates, or compounds of aluminum, silicon and oxygen. If we add the compounds of six elements—iron, calcium, sodium, potassium, magnesium and hydrogen—more than 98 per cent of the crust has been accounted for. These six elements, together with the first three, also appear in soils, clays and shales. But direct chemical analysis is of little value in describing the nature of such materials. Many chemical individuals may be present in variable amounts, and the extreme subdivision of any one of the individuals may contribute qualities that dominate the mixture.

Jan 1, 1939

By J. Morgan Clements

Petroleum has been known in Japan since at least 668 A. D., for a picture shows the presentation, during that year, to the Emperor Tenchi (Tenji) of "burning water" and ('burning earth" by his subjects from Echigo Province, which today is the largest producer of petroleum in Japan. The burning water was doubtless petroleum and the burning earth either bituminous shale or oil-soaked earth or rock from near the oil seepages. The early methods of getting the oil were simple and similar to methods used today in Japan and in China. Where the seepages occurred, trenches or shallow wells were dug along the seepages and allowed to fill with oil, which was then bailed out; in some cases, they filled with oil and water and overflowed. During the 300 years following 1500 A. D., the use of petroleum in Echigo Province seems to have increased considerably, as compared with earlier centuries, and records show that in 1818 the depth of the wells had been greatly increased. Doubtless, they passed through the seepages and tapped the shallow oil-bearing strata; probably some of these deeper wells were dug before that time. The real value of petroleum was not recognized until early in the Meiji era, which began in 1868, when the Japanese learned that the kerosene that was being imported was derived from petroleum. Guided solely by information obtained from books, they refined the oil and increased the depth of their wells in order to increase the production. The deepest well, dug by hand, about this time was 894 ft.' (273 m.) and by 1874 the recorded production reached 3499 barrels. In 1876, Benjamin Smith Lyman prepared geological maps of the Echigo oil field, which were the first of such geological maps made in Japan, and based on these a more enlightened development of the oil fields began; the Japanese, however, still dug the wells by hand. Toward the end of the '80s) an American well-drilling outfit was secured, but the efforts to use it failed from lack of experience by the operators. In 1888, a complete well-drilling outfit was purchased and American oil-well

Jan 1, 1923

By W. A. Mudge, Paul D. Merica

One of the most prominent features of our present-day industrial development is the ever-increasing demand put upon materials of construction. Engineering ingenuity, within the past 25 years, has been unusually active, and in some fields at least engineers frankly say that engineering design has progressed as far as the limitations imposed by the properties of the present materials of construction will permit. Consequently, they are today demanding improvement in their working materials and seeking new ones, through the aid of which the present limitations of design may be overcome. The activity of this search is evident in all fields, but it is particularly so in that of structural materials required to be resistant to corrosion. The corrosion resistance of metals and alloys is never absolute and all-inclusive; a particular alloy will withstand some corrosive conditions well and fail utterly under others. Furthermore, other properties, physical and mechanical, required in conjunction with corrosion resistance vary considerably for different commercial applications. One wants a soft, ductile sheet metal resistant to atmospheric corrosion; another, a high-strength alloy resistant to sulfuric acid. The last decade has witnessed active and definite progress in the development of high-strength, corrosion-resisting alloys. In June, 1924, a symposium by the American Society for Testing Materials, on Corrosion-resistant, Heat-resistant and Electrical-resistance Alloys, disclosed no less than 60 commercial alloys the properties of which were described as being suitable for industrial service where corrosion resistance was a feature. Today the number of these alloys has been doubled, at least. In addition, economy in design and construction through decreased weight has given considerable impetus to the improvement of alloys of which the mechanical propprties may be improved by heat-treatment.

Jan 1, 1935