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By M. L. White, J. L. Shafer, C. L. Caenepeel

Often an in situ leach is the only practical economic method for copper recovery from small low grade oxide deposits. The decision to develop a copper property by an in situ blast and leach is strongly dependent on ore grade, tonnage, hydrology, and the copper extraction and acid consumption rates. The inherent leachability of the ore will in part determine the desired amount of fracturing of the ore deposit by the blast in order to obtain a copper extraction rate that is economical. For the last several years Occidental Research Corp. (ORC), has undertaken a modest effort to address the question of how to best identify and determine the information necessary to predict and control the operation of an in situ leach for the economic recovery of copper.

Jan 2, 1979

By Loyd R. Kern

A procedure for determining the behavior of a reservoir under a gas or water injection program was reported by Buckley and Levertt in 1942.1 This method, which allowed the calculation of the phase saturation distribution behind the front of a displacing fluid, has been extended to apply to a more general situation. The reservoir may initially contain flowing quantities of the displacing fluid, or the fluid in the reservoir may be above saturation pressure SO that solution effects are present. Production may occur behind the front as in the case of a well which is produced after breakthrough of the displacing fluid. The calculating procedure is simplified in that the graphical integration necessary to determine breakthrough saturation is eliminated by performing a direct integration and the graphical differentiation necessary to determine saturation distribution is eliminated by representing the displacing phase fraction of the flowing stream by an empirical equation. This representation results in simple expressions for the producing gas or water/oil ratio and cumulative production. INTRODUCTION A method for the calculation of the saturation distribution behind the front (interface between the displaced and displacing phases in a gas injection or water flooding operation) was reported by Buckley and Leverett in 1942. The method leads to a curve for the saturation distribution which is double-valued; consequently, part of' the curve was interpreted to be physically meaningless. That part of the curve which has physical significance was determined by a graphical integra-tion (material balance). In this paper it is shown that the integration may be performed analytically with a resulting equation for the saturation of the displacing phase at the front. The case in which the displacing fluid is initially flowing and the case in which the reservoir is initially above the saturation pressure so that some injected gas goes into solution are included in the integration. The calculations are considerably simplified by representing the fraction of the flowing stream which is oil by an exponential function of saturation. The methods is extended to apply approximately to reservoirs in which wells located between the injection well and the front are produced. An illustrative example utilizing the methods presented is included. RESERVOIR BELOW SATURATION PRESSURE In the case of a water flooding operation or in the case of a gas injection operation in which no gas goes into solution in the displaced oil, the equation for saturation in a linear flow system as a function of time and position as given by Buckley and Leverett is where* q = total reservoir volume flow rate, rvb/day A = cross sectional area of system, sq ft / = porosity of formation x = distance from injection point, ft t = time, days Pj = saturation of the displacing phase /dx velocity of planes of constant saturation, ft/day *The nomenclature used here is not the same as that used by Buckley and Leverett A complete nomenclature is given in Appendix A.

Jan 1, 1952

By Rossiter Raymond

JOHN BIRKINBINE was born Nov. 16, 1844, at Reading, Pa., the eldest son of H. P. M. Birkinbine, widely known as a hydraulic engineer. The family removed subsequently to Philadelphia, where, as a young man he established with his father the office now continued by his sons, after more than 60 years. His education was received at public schools, the Friends' High School in Philadelphia, the Hill School at Pottstown, Pa., and the Polytechnic College of Pennsylvania, where his studies were interrupted in 1863-4 by service in the Union Army, which included participation in the battles at and around Gettysburg. Later, he devoted two years to work in a machine shop; and subsequently he became associated with the late P. L. Weimer, under the firm. name of Weimer & Birkinbine, operating the Weimer Machine Works at Lebanon, Pa. Much of his work was in mining, metallurgy, and blast-furnace construction. As manager for the South Mountain Mining & Iron Co. he carried on experiments with various fuels for iron-ore smelting while maintaining the furnace in constant operation. The carefully recorded results obtained were widely published, and are referred to in text-books by other metallurgists as most complete. From his Philadelphia office he was sent to nearly every State, and to Canada and Mexico, for examinations, reports, constructions or improvements in iron-ore mines, blast furnaces, iron works, water supplies, hydraulic development, irrigation projects, etc., and his engineering knowledge was requisitioned by several European corporations. A number of business trips were made to Mexico, beginning with a visit to the Cerro de Mercado at Durango, before railroads were established in that portion of Mexico, to make a critical examination and report on this "Iron Mountain." Later visits covered other localities and engineering problems, familiarizing him with the major part of the iron industry in Mexico. The late disturbed political conditions in that Republic have retarded the probable enlargement, modernization, and improvement of much of the iron and steel industry of Mexico, upon which he investigated and reported for various capitalists on both continents. One interesting subject included in these reports was a proposed electric furnace, to be operated by energy from water power.

Jan 7, 1915

By J. W. Robinson

The Jersey mine, owned by Canadian Exploration Ltd., has produced nearly five million tons of lead- zinc ore from a flat-lying replacement orebody. A room and pillar method of trackless mining has been used, leaving a checkerboard pattern of 40-ft wide panels, with the hanging wall supported by pillars from 20 to 40 ft in diameter. About 35% of the remaining ore reserve is tied up in pillars. The pillars in the north end of the mine are smaller than the pillars in the south end and each contains about 500 to 1000 tons of ore. The larger pillars in the south end contain from 2000 to 8000 tons of ore each. The pillars vary from 15 to 60 ft high, depending on the thickness of the orebody at any given point. They are irregularly shaped, and from 20 to 40 ft in diameter.

Jan 12, 1963

By Ilmar Stöckel, Gösta Harlin, Agne Rustan

INTRODUCTION This chapter is a continuation of the studies by Rustan and Stockel (1979, 1980) on techniques for automating ventilation in Swedish mines and construction works. The studies have been financed by the Swedish Board of Technical Development. As a result of the studies it has been recommended that a good solution to diesel exhaust emission would be automatic, step by step control of the fans near the working place. Diesel vehicles are the major polluters underground in the mines. Therefore, we have suggested that diesel vehicles regulate the fans The goal of the continued study has been to find a way for active diesel vehicles to start and stop gallery fans at both intake and return air. In this paper different methods for activating fans are discussed. The best methods are chosen and tested in the mine. In this study we have found that change of temperature is an inexpensive and effective way to start and stop crosscut fans in sublevel caving and radio signals seem to be an attractive system for starting and stopping gallery fans . This work has been done in close collaboration between LKAB in Kiruna and the University of Luleå, Divisions of Electronics and of Mining and Rock Excavation. An advisory group for the project has been established with ventilation experts from the mines, representatives of the local mine workers' unions, and authorities from the local offices of Governmental Inspection of the Workers Safety. VENTILATION SYSTEM STUDIED In the project the ventilation system at LKAB in Kiruna was studied. The mining method used is sublevel caving with 9-13 m slice height. The air above ground is heated in winter by hot water and the main fans push the air down to a main distribution level along the 4000 m long and about 100 m wide ore body. From the distribution level, air is taken through shafts down to the sublevels, where it is pushed through the levels by local gallery fans on both the intake and return sides, Fig. 1.

Jan 1, 1981

By Rip Thompson

ALTHOUGH the metallurgical treatment for the Ophir Hill tailings was developed more than 20 years ago and in the interim a vast amount of experimental work was done with later-developed flotation rea-gents, it was found necessary to revert to the original oil reagents and their combina-tions with specific chemical reagents in order to obtain results of economic value. This is of especial interest because in present ore-treatment investigations later-developed flotation reagents are used almost exclusively and the coal-tar deriva-tives, except in certain patented reagents, are virtually neglected. These coal-tar oils and derivatives still have a definite field of application, especially in the treatment of some oxidized ores when modified sulphidi-zation is desirable. The Ophir Hill tailings deposit is in Ophir Canyon, Tooele County, Utah, about 55 miles southwest of Salt Lake City and 25 miles south of the Tooele smelter of the International Smelting and Refining Co. A road good for trucks leads directly from the Ophir mill to the smelter.

Jan 1, 1940

By William E. Hubbard

During the last decade the known reserves of petroleum in the United States have increased from about five billion to over thirteen billion barrels. From the standpoint of public welfare the existence of these known reserves presents an undeniably favorable picture, but viewed from the position of many a harassed operator the blessing has not always been considered an unmixed one. Along with this increase in excess reserves, curtailment of production has come into being as a matter of necessity and the principle of proration as a matter of equity. As a practical matter it has been considered necessary to curtail the production of old wells as well as that of new wells in a pool. The right of new pools to produce has been recognized, and the allowable for them has come partly from increased market demand and largely from the allowables already enjoyed by the developed pools. The natural result—a downward trend in daily per-well allowables—has been especially felt by Texas operators. This trend may be illustrated by Table 1, which comprises the five active areas in Texas, and from which may be noted the following: 1. The average daily allowable per well has decreased about 53 per cent in three years. 2. Of the 184,000-bbl. increase in total allowable for the five areas, 29,000 bbl. came from the increase in state demand and 165,000 from the combined allowables of the remaining pools in the state.

Jan 1, 1937

By Thomas Egleston

The adoption of the regenerative principle for burning fire-bricks, pottery, etc., has been delayed beyond what would naturally have been expected, because there bas been until recently little necessity for high heat in burning such material. But the introduction of pro-

Jan 1, 1887

By H. H. Kaveler, Z. Z. Hunter

Variation of the horizontal permeability (parallel to the bedding plane) in the vertical section of reservoir rocks has long been observed as a characteristic of a normally heterogeneous system which reservoir rock represent. The use of a recently developed water injection profile device offered opportunity to measure with a high degree of reliability the rate of inflow of water into Burbank sandstone in wells previously cored. Water injection profiles were not correlative with core permeability profiles in such wells. Apparently the vertical permeability substantially influences the flow between strata in a formation in a manner as to void the usual conclusions that have been drawn from consideration of the horizontal permeability measurements alone. The results obtained in comparing water injection profiles with horizontal permeability profiles suggest that many of the usual production operations based upon "selective" behavior or treatment of rock exposed in well bores need to he re-valuated and re-examined. INTRODUCTION Petroleum reservoir rock are heterogeneous systems. Heterogeneity exists in respect to lithologic character insofar as such rock are composed of distinguishable solid phases. Heterogeneity also exists in respect to certain properties, such as porosity and permeability, that vary due to variation of the physi-cal structure of the rock. Except in exceptional cases, both the horizontal permeability (measured parallel to the bedding planes) and the vertical permeability (measured perpendirularly to the bedding planes) exhibit significant variation in any common source of supply. The variation in horizontal permeability. as reflected by con. analyses. has drawn the greatest attention of petroleum technologists probably out of the general notion that the mass movement of fluids in a reservoir is predimonantly in the horizontal direction. Furthermore, in the usual case, the rock permeability measured in the horizontal direction is greater than that in the vertical. The variation of horizontal permeability of reservoir rock has been the basis for developing a number of operating practices and procedures intended to improve the petroleum production operation. Many such procedures are referred to as "selective" in the sense that the practice is intended to control the flow to a more. or less. permeable interval within the common source of Supply. It is often said that such practices are "tailored" to the permeability profile. The practices referred to involve, among others, the following: selective perforation of casing; selective shooting, acidizing and plugging: plugging back to intervals of low permeability; and, regulation of flow to prevent coning of water or gas, or irregular encroachment of water or gas. Certain expressed notions involving a concept of "by-passing," or "trappingl" that are held to be particularly harmful in causing the avoidable loss of recoverable petroleum have grown from observed variations in the horizontal permeability. Oftentimes estimates of the reserve of a common source of supply are tempered by conclusions relating variation in horizontal permeability to recover-ability of the oil-in-place. Certain conclusions attributed to the significance of the variation of the horizontal Permeabilitv often extend to the design and operation of pressure-maintenance projects involving both water flooding and gas-injection. Many advocate increasing the number of injection wells, advocate maintaining uniform and equidistant input-output well patterns, or advocate so-called "dispersed" gas-drive techniques rather than gas-cap injection because the permeability profile of cored wells is supposed to indicate that "by-passing" or "trapping" would otherwise exist. It is important, therefore, to have an opportunity to test whether the variation in the horizontal permeability found through core analyses of a typical reservoir rock is sufficient to establish the paths of fluid flow in a reservoir. It is particularly important to have an opportunity to determine whether flow at the sand face of a well conforms to the permeability profile as established by core analyses. In that manner, the merit of certain 50-called "selective" operating procedures and other notions may be evaluated. The purpose of this paper is to compare horizontal permeability profiles of wells in the Bartlesville (Bur-bank) sandstone with water injection profiles, for the purpose of showing that there is no correlation between the horizontal permeability of a core and the water intake characteristics of a typical sandstone. GENERAL CHARACTERISTICS OF BARTLESVILLE (BURBANK) SANDSTONE The Bartlesville sandstones of Northeastern Oklahoma are off-shore bar deposits.' Although other reservoirs had different processes associated with their deposition or with the formation of their porous, permeable structure, the l!artlesville sandstones on which these field Fields were made are, in every respect. typical petroleum reservoir rock. The permeability of the Bartlesville sandstones shows a typical variation in both the horizontal and vertical direction. Furthermore, the permeability profile logs of wells in any pool are not correlative, even as between wells as close as 660 ft and 330 ft apart.'. The same condition exists in such sand-tones as the Jones Sand at Shuler' and is the ordinary and usual characteristic of reservoir rock. THE FIELD DATA The data reported herein are those obtained from coring of nine wells on the center of ten-acre locations for the purpose of providing water-injection wells in the Bartlesville (Burbank)

Jan 1, 1952

By H. B. Fuqua, B. E. Thompson

The area discussed in this paper, commonly known as the West Texas district, is easily divisible into three geologic provinces, the Midland Basin to the east, the Delaware Basin to the west and the West Texas structural platform separating these two. Production in Garza, Scurry, Mitchell, Howard, Glasscock, Irion, Reagan and central Crockett counties is associated with the east flank of the Midland Basin. That in Loving and Reeves counties is associated with the Delaware Basin. All other production and developments discussed in this paper belong to the province of the West Texas structural platform. Because of certain developments that have occurred during the past year, it has been found necessary to slightly revise one of the fields as grouped by Mr. Reith in last year's paper1. The Scarborough-Leck field has been broken down as follows (Table 1): The Leck field is shown separately because it is producing from dolomite; while the Scarborough area, producing from sand, is regrouped and designated as " Scarborough-Kermit-Halley," which includes the producing sand belt across Winkler County from Ward County to New Mexico. It is believed that this is a more logical division of Winkler County and that considerable future work will be avoided by making this change before further production figures have accumulated under the present set-up. A number of new fields are listed in Table 1, some of which may represent extensions of other produeing arras. The authors, however, are inclined to believe that they represent new fields. In either event, less work is involved ill adding two areas together, if they later prove to be one, than in attempting to separate a maze of production data into two fields after they have been erroneously carried as one for a number of years. The Howard-Glasscock field is designated in this review as the Chalk-Roberts field and the Denman production on the Howard-Mitchell County line is included in the Iatan field. Development during 1934 Development in West Texas during the year 1934 showed a marked increase over the previous year both in exploration and ill exploitation

Jan 1, 1935

By Reginald S. Dean

THE widespread occurrence of manganese in low grade oxide and carbonate ores not amenable to mechanical concentration has led to extensive investigations of hydrometallurgical methods for producing a pure manganese compound suitable for further treatment. Manganese carbonate is the preferable compound. This product when fully crystalline and of not too fine crystal size is easily filtrable and stable in air. It can be converted to other compounds such as the oxides by heating in air or can be reacted with acids for producing salts. A useful hydrometallurgical process must produce relatively concentrated solutions that can be purified easily, reagents must be cyclically used, and heat requirements must be small. Neither the ammonium sulphate nor sulphur dioxide leaching processes that have been tested extensively fulfill these 'requirements. Other hereto-fore proposed processes have obvious limitations and have not been tried on a large scale. The present process is based on the discovery by the writer of a new group of aqueous manganese-ammonia complex solutions highly concentrated in ammonia, which permit rapid solution of manganous oxide to concentrations of 80 to 100 g Mn per liter and from which a fully crystalline, easily filterable manganese carbonate is precipitated by the addition of carbon dioxide and partial ammonia removal. Although the process may be carried out with many ammonium salts, commercial advantages dictate the use of ammonium carbamate, which is obtained when CO2 is passed into concentrated aqueous solutions of ammonia. If the carbamate is used, the only reagents, ammonia and C02, are volatile and may therefore be recovered from solutions and residues by heating, thus eliminating washing and extensive evaporation. Impurities are controlled easily as most metal oxides are either insoluble in the lixiviant or fail to precipitate with the manganese carbonate. Others are controlled by sulphide addition. The process has been tested extensively on a small scale on a wide variety of ores; including Three Kids, Artillery Peak, Cuyuna, and Chamberlain; as repre-

Jan 1, 1952

S. Tandanand, Twin Cities Mining Research Center, U. S. Bureau of Mines As an addition to the fine reviews on drilling presented in the foregoing papers, we feel it would be appropriate to mention briefly some work in this area by the U. S. Bureau of Mines. The Bureau has had under way for several years at its Twin Cities Mining Research Center studies directed toward a better understanding of basic drilling mechanisms. The work includes drillability investigations with diamond rotary, and with percussive drilling systems, as well as fundamental studies of rock behavior under drill bit types of loading. Results of our work to date have contributed the following to the state of the art. MECHANISM OF ROCK FAILURE-Rock fragmentation through use of mechanical energy systems, including drilling systems, consists of two major components-machine and rock. The two components are related to each other by their functional behavior and their resultant motion which the components mutually influence. Forces in the systems are transmitted directly to the bit which in turn induces stresses in the rock. When the induced stresses exceed the strength of the rock, the rock fails resulting in penetration. Rock strength is a function of the forces applied to the rock. Stresses under a drill bit, regardless of bit configurations, are essentially compressive, resulting in a condition where the rock has the highest resistance to failure. The ratio of principal stresses induced under drill bits is an indication of the mode of failure in the rocks. Initially, compressive stresses under the drill bit cause rock to undergo inelastic deformation. The impression observed at the first stage of crater formation under the drill bit shows that rock is no longer elastic. Associated subsurface failure at this stage precedes total rupture which subsequently appears at the rock surface. Thus, explanation of crater formation, by applying theory of elasticity alone, is likely to be over-simplified. ENERGY VERSUS VOLUME OF ROCK REMOVED-Experimental results show that energy per unit volume of rock removed is constant for a particular rock and bit type. Rock offers a definite resistance to penetration, depending on the method of the energy application; this may be defined as the drilling strength of a rock. Energy consumption in a drilling system may be divided into two components: 1) Energy required to move the machine parts; and 2) energy consumption in breaking rock. Component 1 is dependent on the type of the machine. Component 2 is dependent on the strength properties of rock and the efficiency of the bit in rock cutting. The sum of the energy required in both components determines the total energy required in breaking rock. Our work in this area has included consideration of both diamond and percussive drilling systems. PENETRATION RATE-For a drilling rate expression to be useful in predicting field performance, it should include the operating characteristics of the drilling machine. Eq. 37, for example, is simply a statement of the fact that the drilling rate is determined by the power output of the machine (2pNT) and the power requirements to break the rock in the hole (AER). In order to predict the performance of a particular drill and the effect, for example, of the rotary speed, on the drilling rate, R, Eq. 37 must be modified to include the

Jan 1, 1967

By Frank R. Milliken

SCOPE THIS paper is a running commentary on metallurgical problems and developments, stressing ilmenite flotation, since the start of operations five years ago, at the mill of National Lead Company, Titanium Division, Maclntyre Development, Tahawus, New York. [ ] GENERAL In early 1941, when, world conditions threatened to cut off the supply of ilmenite (obtained largely from India) to this country, the National Lead Company started to develop and bring into production their Maclntyre Development. This operation supplied the bulk of the ilmenite used during the war period for the manufacture of the much needed titanium pigments. Maclntyre Development is at Tahawus, New York, on the headwaters of the Hudson River in the center of the scenic Adirondack Mountains. A general description of the operation was given in the Adirondack Issue of Mining and Metallurgy for November 1943. Operating tonnages and production have increased since 1943, however. Nearly 10,000 tons of ore and waste is broken and loaded daily in the open-pit mine. About half of this tonnage is ore, from which is produced nearly 800 tons of ilmenite concentrate and 1600 tons of magnetite concentrate daily. ORE-TYPES From an ore-dressing standpoint, there are five rather distinct ore types and two waste-rock types in the mine. The ore types are shown in Table 1. The anorthosite waste is a coarse-grained white rock, largely labradorite feldspar. The gabbro waste is generally finer grained, and contains, in addition to feldspar, 35 to 75 pct iron silicates such as hornblende, pyroxene, garnet and biotite. A minor mineral mineralogically, but important metallurgically, is apatite. A few calcite

Jan 1, 1947

By George C. Toland, Ronald E. Versaw

Most existing impoundment ponds and dams leak effluent into the soil or rock upon which they are constructed. However, proposed environmental legislation will require very stringent control of the release of toxic effluents such as cyanide. More exacting investigation, design, and construction techniques than have been used in the past will be required to satisfy these new regulations. The types of field and laboratory investigations required to develop the data for the design of an impoundment system containing toxic effluent are discussed, together with the technical considerations necessary to design this system. Design topics include reservoir sealing with natural and man-made materials; embankment sealing; embankment design considering stability, surface hydrology, capacity, and downstream catchment basins; and special implications of cyanide effluents.

Jan 1, 1977

By L. Edeleanu

Crude petroleum is a mixture of various groups of hydrocarbons and some bodies containing oxygen or sulphur.

Jan 1, 1915

By Charles R. Simcoe

It was pointed out in a recent paper'g that the initial flow stress of as-quenched martensite is very low even in an alloy steel with an M, well above room temperature. It was also shown that the high ultimate tensile strength resulted from a very high rate of work

Jan 1, 1967

By Douglas M. Smith

Silver-gold ratios were studied at the Tayoltita epithermal vein deposit using channel sample, channel sample line, stope, ore body, and vein sample populations. The ratios are highly variable among individual channel samples (25:1 to greater than 500: 1) with both high and low values randomly distributed within ore bodies and veins. Whole vein ratios for the 14 most important ore producing structures range from 44: 1 to 105:1, and show zonal distribution relative to two small granitic stocks, low values closest to the intrusives. The zoned nature of the deposit suggests that the stocks, apophyses of an underlying batholith of late Eocene age, were the heat engines which powered the hydrothermal system responsible for ore deposition.

Jan 1, 1980

By W. C. Krumbein

GEOLOGICAL problems are approached from a geometrical (space relations) viewpoint, a kinematical (time sequence) viewpoint, or a dynamical viewpoint. The first two require sound training in conventional geology and in field methods. The third approach requires a solid foundation of chemistry, physics, and mathematics. Modern training for geologists should include close integration of basic sciences with geological principles.

Jan 1, 1941

By Edward Thomas

ROCK bolting, third great change in postwar underground mining, is inseparably tied to the other two changes: better drilling and mechanized mining. Mechanized mining provided the impetus, when conventional supports restricted maneuver-ability of equipment-while carbide-tipped bits lent the means of drilling required holes cheaply. With the need and the tools at hand development snow- balled. In just six years, from January 1948 to January 1954, some 800 mines adopted bolting for systematic support, and over 100 of these mines now use rock bolts exclusively. Simultaneously, foreign mines have adopted the idea, but to a lesser extent. What held back this major change? The concept of fastening loose material to unbroken and apparently solid material is probably as old as mining itself, and sporadic use has been reported from virtually every mining region in the world. But falls of rock have always been the greatest source of both fatal and nonfatal accidents in underground mining and miners have understandable reluctance to work under roof or back material if they even suspect that it might be hanging like a "sword of Damocles" -supported only by a thin bolt.

Jan 11, 1954

By J. C. Smock

THE magnetic iron ores of New Jersey are found in the northern part of the State, in the Highland Mountain range, which runs from the New York line on the northeast, to the Delaware River, near Easton, at the southwest. The same range continues across Orange County to the Hudson River, and towards the southwest it is known in Pennsylvania as the South Mountain. It is more properly an elevated table-land, quite deeply furrowed by several narrow, longitudinal valleys, and shorter cross-valleys or gaps. The ridges or lines of elevation, as well as the lower valleys, conform in their general direction very closely to the general trend of the whole belt or table-land, that is, from northeast to southwest. This also agrees with the prevailing strike of the rocks. This great uniformity in the altitudes of the hills and ridges, and the direction of the lines of depression corresponding to the strike of the strata, point to an original table-land, which, through the long action of denuding agents, has been quite deeply eroded, giving rise to the present surface configuration, so that some of the former and uniform features have been partially obliterated. The very few cross-valleys or depressions are much more irregular in their course, and serve as outlets through which the drainage is carried either into the Kittatinny Valley on the northwest, or to the broad, red shale and sandstone plane bounding the highlands on the southeast. The area of this highland

Jan 1, 1874