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By Faustino Roel

AMONG the problems confronting the mining engineer in Mexico in recent years, labor conflicts have come to occupy s prominent place. Each day they have become more serious and frequently have caused- the ruin of companies. It is therefore necessary for the engineer to understand the Federal Labor Law, the rights and obligations of companies and of their workmen, and the reasons for conflicts; to keep in mind the expense which may be caused companies; and to endeavor to avoid difficulties as far as possible. Our labor legislation is primarily to protect the workman and the constant tendency of the tribunals, including the Supreme Court of Justice, is to support the work- man in his demands against employer$, even at times granting him more than he asks, with no limit other than the economic capacity of the company to com-

Jan 1, 1937

By Charles T. Holland, David A. Olsen

Considerable work has resulted in the development of a formula by which the strength of coal pillars for an L to T ratio of up to 12 may be estimated. One of the factors involved in this formula is the coefficient of friction between the coal pillar and the adjacent rock with which it is in contact. This paper presents the results of studies on sandstone, limestone, shale and coal and the coefficient of friction between coal and the other three under wet and dry conditions. With the coefficients of friction thus determined and the use of results obtained earlier by Meikle and Holland, it seems probable that coal pillar strength may be more closely estimated. Several investigators1-3 have found that the com-pressive strength of cubical coal specimens can be correlated by an equation such as

Jan 1, 1969

By P. Chiotti, G. R. Kilp

Thermal, metallographic, vapor pressure, and X-ray data were obtained to establish the phase diagram for the zinc-zzrconiz~m system. Five compounds corresponding to the stoi-chiometric formulas ZrZn, ZrZn,, ZrZn,, ZrZn,, and ZrZn14 were observed. All these compounds, with the exception of ZrZn2, which melts congruently at 1180°C under constrained zinc-vapor conditions, undergo pexitectic reactians. The temperature at which the zinc vapor pressure is I atm for a series of alloys was determined from vapor-pressure measurements. The data obtained are summarized in the construction of a I-atm-pressure phase diagram and a phase diagram corresponding to a pressure of less than 10 atm. THE purpose of this investigation was to establish the phase diagram for the zinc-zirconium system. Thermal, metallographic, vapor pressure, and X-ray data were employed in determining the phase regions. Partial investigations of this system have been conducted by Gebhardt1 and Carlson and Borders.' Carlson and Borders studied the high-zirconium region and established the existence of a eutectic at 69 wt pct Zr with a melting point of 1015°C. The terminal phases of the eutectic horizontal were shown to be an intermetallic compound ZrZn and a solid solution of ß zirconium containing 21 wt pct Zn. The ß solid solution decomposes into ZrZn and a zirconium at 750°C. The eutectoid composition is given as 15 wt pct Zn, and the solubility of zinc in a zirconium at temperatures below 750°C is indicated to be negligible. Gebhardt studied the zinc-rich region and observed a lowering of the melting point of zinc from 419.5" to 416°C and temperature horizontals at 545" and970°C. Some preliminary observations by Chiotti, Ratliff, and Kilp were reported by Hayes.2 pietrokowsky3 has reported the compound ZrZn2 to have a cubic MgCu2 structure with ao = 7.396A. MATERIALS AND EXPERIMENTAL PROCEDURES The metals employed in the preparation of alloys were Bunker Hill slab zinc or Baker analyzed reagent granulated zinc, both 99.99 pct pure and hafnium-free iodide-process crystal bar zirconium obtained from the Westinghouse Electric Corp. The zirconium contained 200 ppm Fe, 200 ppm Si, 100 ppm C, and minor amounts of other impurities. The zirconium was milled or machined into thin chips or shavings. These were cleaned with a nitric-hydrofluoric acid solution, rinsed with water, and acetone, and dried just prior to their use in alloy preparation. The granulated zinc was similarly cleaned using dilute nitric or hydrochloric acid. Weighed quantities of these materials, 20 to 30 g total, were mixed and pressed at 20,000 to 70,000 psi to give relatively dense compacts. During the early part of this investigation the pressed compacts were placed in MgO-15 wt pct MgF, crucibles which were then sealed inside of quartz ampules. The compacts were given various prolonged heat treatments prior to their use for thermal analyses, or vapor-pressure measurements. Because of expansion of the compacts and the relatively high zinc vapor pressure it was difficult to heat to the melting temperatures of the alloys without failure of the quartz ampules. Homogenization at temperatures below the melting temperature gave brittle, porous alloys unsuitable for metallographic examination. It was also difficult to prevent condensation and segregation of zinc on the colder parts of the quartz ampules during heating and cooling operations. These problems were eliminated to a great extent by the use of tantalum crucibles. Tantalum proved to be a satisfactory container with little or no reaction between the alloys and the tantalum. Small tantalum thermocouple wells were successfully welded in the bottom of these crucibles. Pressed compacts were sealed inside the tantalum crucibles by welding on preformed caps under an argon atmosphere. Heat treating and differential thermal analysis were combined into a single operation. The experimental sample assembly is shown in Fig. 1. This assembly was enclosed inside a stainless-steel tube heating chamber which could be evacuated and filled with an inert gas. The thermocouple leads were brought out of the heating chamber between two rubber gaskets used to provide a vacuum seal for the water-cooled head. Most of the compounds in this system undergo peritectic decomposition. After heating above the temperature of a particular peritectic horizontal the sample was cooled to just below the peritectic temperature and held at temperature for several hours. The sample was then reheated through the peritectic temperature and the size of the thermal arrest, if still present, compared with the one previously obtained. If the thermal arrest was not characteristic for the alloy composition being investigated its magnitude diminished and repeated cycling and annealing eventually eliminated it. The peritectic thermal arrests characteristic of a particular composition were established in this manner.

Jan 1, 1960

By R. W. Raymond

Recent literary labors have led me to the compilation of the following tables and estimates, which may possess interest for my colleagues in the Institute, and which are here submitted without comment.

By L. H. Morris, M. Mordecai

The emission of firedamp from the strata surrounding active workings of longwall coal faces normally follows a cyclic pattern associated with the mining operations being carried out on the face. Mining a coal seam disturbs the uniform distribution of overburden weight such that the working is enveloped by a region of high stress, both above and below the seam, advancing with the coal face. There is a decrease in stress as the strata is relaxed following the passage of the face (1). The paper describes experimental results obtained during the initial investigations of a study intended to examine the permeability of samples of coal measure strata under various triaxial stress conditions. Several investigators have studied the effect of stress on the permeability of rock, usually in the field of oil reservoir engineering. Two general lines of approach are evident. One used by among others Fatt and Davies (2), McLatchie et a1 (31, Brace et al (4) and Gunther (5) was to subject a rock sample to hydrostatic pressure. Gas or water would be passed through a sealed core mounted inside a high pressure hydraulic bomb. The second approach, favoured by Wilhelmi and Somerton (6) and also by Gray et a1 (7) was to employ a so-called 'triaxial' state of stress. Here radial confining pressure and axial stress are applied independently. The permeability is measured in the direction of the axial load. With the exception of Gunther who tested coals and Brace et a1 who tested a granite, the rocks used have been sandstones with permeabilities generally appreciably higher than British coal measure rocks.

Jan 1, 1971

By R. Kossowsky

In the course of a study concerned with structural stability of precipitation hardening nickel base super -alloys after exposures to elevated temperatures, some interesting effects of hydrostatic pressure treatment on Rene were observed. The evidence presented below suggests that hydrostatic pressure treatment of the solution heat-treated alloy can affect the dispersion of the y' (Ni3Al) phase upon subsequent precipitation heat treatment and long time aging. Rene 41 alloy has the following nominal weight percent composition: Al B C Co Cr Fe Mn Mo Ti Ni 1.4 0.006 0.7 11.3 19.2 1.0 0.05 9.4 3.3 balance The effect of successive pressure, precipitation heat treatment, and long time aging on the microstructure of this alloy was determined by subjecting a number of alloy buttons to five different thermopressure treatments. Pressure and precipitation heat-treatment parameters are listed in Table I. Fig. 1 shows y' morphology* of specimens in groups I and 11. The treatment results in a fine dispersion with particle size on the order of 950 and 1350A, respectively, see Table I. Fig. 2 shows the morphology of y' precipitate in

Jan 1, 1967

By Colin M. Sargent

ALTHOUGH annealing twins are frequently observed in many fcc metals, their occurrence in aluminum is relatively rare. ~ahn' in his review of twinning has listed only a few references to observations of twins in aluminum, e.g., Refs. 2 and 3. They have also been shown to occur in evaporated aluminum layers.4 During the present work, several annealing twins were studied in aluminum. The specimens of 1099-grade aluminum had the following thermomechanical treatment: deformed 90 pct by rolling, partially re-crystallized, further deformed 60 pct to a final thickness of 100 p, then annealed for 24 hr at 120°C. This treatment produced several annealing twins—-about ten per electron microscope specimen. The specimens were produced by the window technique and examined in a Phillips E.M. 200 operating at 100 kv. A typical twin boundary is shown in Fig. 1. For several of the twins studied the twin plane could be tilted so that it was parallel to the electron beam, e.g., Fig. 2. The associated diffraction pattern, Fig. 3, shows the twinned relationship between the grains. The twinning plane in each case was (111). Use of a reflection common to both the twin and the matrix,* i.e., using reflecting planes parallel in the twin and the matrix, the coherent twin boundary becomes invisible and only the noncoherent segments of the stepped boundary are seen, e.g., Fig. 4. Trace analysis of the boundaries showed that the long straight portions were invariably the twin plane; i.e., these portions are coherent. The planes of the shorter segments are shown by Fig. 5 to be (551 1, (7111, and {211).

Jan 1, 1969

By J. W. Cuthbertson, R. A. Cresswell

THE constitution of Cu-rich alloys with 1.5 to 13.5 pct Sn and 0.25 to 3.0 pct Be and the precipitation-hardening characteristics of alloys with 1.5 to 13.5 pct Sn and 0.25 to 1.0 pct Be have been examined. The hardness and tensile strength of the alloys examined increase markedly after solution treatment at 700°C followed by heat treatment at temperatures between 200" and 450°C. By a combination of cold work and heat treatment, hardness values similar to those exhibited by commercial Be-Cu alloys containing 2.25 pct Be can be obtained with ternary alloys containing 9 pct Sn and 0.75 pct Be and containing 10 pct Sn and 0.5 pct Be. Marked hardening effects occur with alloys containing even less beryllium. By heat treatment alone, a hardness value of 310 diamond pyramid hardness can be obtained from an alloy containing 10 pct Sn and 0.75 pct Be. Preliminary tensile tests have shown that an ultimate tensile strength of 110,000 psi with an elongation of 23 pct is obtainable by precipitation hardening an alloy with 8 pct Sn and 0.75 pct Be. The precipitation-hardening process has been followed microscopically for certain alloys and the inference is that, while the initial hardening effect is probably explained by the precipitation of the ß phase of the Cu-Be system, further hardening, proceeding at a much slower rate, also occurs, apparently as a result of precipitation of phases of the Cu-Sn system, particularly precipitation of the 6 phase at temperatures below 350". The presence of the e phase of the Cu-Sn system in certain alloys at temperatures below 350°C has been confirmed. Tin-bronzes are widely used in engineering applications where a combination of high strength and good resistance to corrosion is wanted. The maximum strength is induced in these alloys by cold working, and it would be an advantage for many purposes if high strength could be achieved alternatively by an age-hardening process. While Cu-Sn alloys have a good fatigue resistance they can be surpassed in this respect by Cu-Be, but the use of the latter alloy is limited by its high cost. If, by adding beryllium to tin-bronze, the properties of the respective binary alloys could to some extent be combined, a most attractive alloy should result. As pointed out by Raynor,¹ beryllium is on the borderline of the zone of favorable size factors for copper, and the solid solubility of beryllium in copper is consequently much more restricted than if the size factor were strongly favorable. The size factor is sufficiently favorable, however, to permit an increase in solid solubility with rise in temperature, and there is thus a composition range in which CU- Be alloys are susceptible to hardening by precipitation heat treatment. Although the a phase of the Cu-Sn system is similarly susceptible to precipitation treatment, the time necessary to establish equilibrium in commercial alloys of this type is usually so great that age hardening becomes impracticable. The addition of beryllium to Cu-Sn alloys would appear to offer a means of conferring on the latter useful age-hardening properties. Masing and Dahl² and others have, in fact, shown that the addition of beryllium to Cu-Sn a solid solutions renders these alloys susceptible to precipitation hardening and after such hardening confers on them an encouraging improvement in physical properties. If this improvement could be achieved by the addition of substantially smaller amounts of beryllium than are customarily found in binary Cu-Be alloys, the ternary alloys should possess economic advantages which might make them more attractive than the binary alloy for some applications. Binary Systems Copper-Tin: The constitution of these alloys is now reasonably well known and is summarized in the equilibrium diagram published by Raynor.³ The following observations, due to Raynor,¹ on the structure of those phases of the Cu-Sn system that are likely to be found in the ternary alloy system will facilitate the subsequent discussion on the examination of that system. The ß phase is an electron compound at the electron-atom ratio 3:2 and has a body-centered cubic crystal structure. This phase is stable only down to 586°C, at which temperature it decomposes eutectoidally into the a and y phases. The y phase has a structure that is also based on the cubic system. This phase is stable down to 520°C, at which temperature it decomposes eutectoidally into the a and d phases. The d phase is an electron compound (Cu³¹Sn8) which has a crystal structure analogous to that of 7 brass. This phase is stable from 590" to 350°C; on prolonged annealing at the latter temperature it breaks down into a mixture of the a and E phases. The e phase is an electron compound (Cu³Sn) having the electron-atom ratio 7:4. Its structure may be regarded as a superlattice based on the close-packed hexagonal system. This phase is stable from 676°C to room temperature. The primary solid solubility of tin in copper increases to a maximum of 15.8 pct as the temperature falls from that of the peritectic reaction to 586°C. The solid solubility remains constant from 586" to 520°C. At lower temperatures the solubility decreases progressively. Below 350°C the fall in solubility is pronounced and is associated with the precipitation of the e phase. This precipitation is very sluggish and does not normally occur under service conditions. Copper-Beryllium: The Cu-Be system has been investigated by Borchers' and others. Raynor5 summarized the present state of information on it.

Jan 1, 1952

By M. Kashiwada

The zinc leach residues are introduced into waelz kiln to fume volatile metals and before the end of 1967, the waelz-fume containing zinc, lead, cadmium and indium was directly recycled back to the leaching process for the production of electrolytic slab zinc. However, since 1968, we have been recovering with success those valuable metals contained in the fume separately instead of direct leaching. According to the improved process, the waelz-fume, after being mixed with chloridizing agents, is fed into the rotary kiln to be roasted, wherein most of lead and cadmium content is collected as fume and most of zinc remains in the calcine. Zinc calcine thus obtained, containing 70 to 75 per cent zinc and, less than 1.0 per cent lead is sent to zinc plant for further recovery and the fume containing 40 to 50 per cent lead and 3 to 6 per cent cadmium is further processed to recover lead, cadmium and indium. The advantage of this process can be secured to the utmost when it is combined with the following subsequent treatments. (a) Blast furnace smelting of non-magnetic waelz slag to recover copper, silver and gold as matte. (b) Gallium recovering process from magnetic waelz slag. (c) Soda process of lead bearing cake produced after removing cadmium and indium from the said fume. Thus the extractions of zinc, lead and cadmium from leach residues account for 87 per cent, 72 per cent and 85 per cent respectively.

Jan 1, 1970

By Van Der Muelen P. A.

SOME time ago, the writer received from W. 0. Borcherdt, Manager of the, works of the Bertha Mineral Co. at Austinville, Va., several specimens of a dense yellowish slag-like material, containing cavities showing clear needle-like crystals, and representing a product formed by the fumes of zinc oxide and basic lead sulphate from the oxide furnace, attacking the firebrick lining of the flues. The matrix, which is of a greenish-yellow color, is made up chiefly of an amorphous glass, carrying numerous crystals, the latter being well-defined, clear, and transparent, but colored a very light yellow by small amounts of ferric oxide. A number of the crystals were carefully separated from the matrix and tested with the blowpipe. They have a fusibility of about 2, yield a globule of lead and a coating of lead oxide before the blowpipe on charcoal, and contain some zinc. Their hardness is 5 to 6. 1 Fig. 1. Under the microscope the crystals appear to be made up of a prism, with narrow faces, and a fairly large pinacoid, but unfortunately show no terminal faces (Fig. 1). Between crossed nicols they gave parallel extinction in. the three planes containing the crystallographic axes, and are therefore orthorhombic. The index of refraction is high. A number of the best crystals were measured on the reflection goniometer, the angles given below representing the average of measurements made on different individuals. mm = 46° 52' mb = 66° 34' a:b:c = 0.4334:1 :?

Jan 5, 1917

By J. L. O’Brien, M. Suenaga, K. M. Ralls, V. F. Zackay

The effecls of aging a1 400°C on tile resistive transition at 4.2°K of a superconducling 70Zr-30Nb alloy are reporled. Microstrclural changes were studied by critical temperature, resistiue critical field, residual resistiuily, and microhardness measurements and by X-ray diffraction, optical microscoby, ad replication electron microscopy. The result of the aging treat- A defect-free Type 11 superconductor in a magnetic field above Hc1 cannot sustain a transport current runt is a fine array of w-phase pavticles with a mean center to center interparticle spacing of about 800A. At an aging time of 300 hr the maximum onset critical current density is rcached. The particle size at the maximum current density if about 4202. At times longer than 300 hr effective particle impingement leads to lower onset critical current densities. perpendicular to the applied field without power loss in the sample.'-3 This power loss is due to flux line motion caused by the Lorentz force and is manifested by a longitudinal voltage.4-6 When defects are present in the material, flux lines are pinned until the Lorentz force exceeds the "pinning force". That is, it is thought that flux lines reside in free-energy wells existing at the defects, and the critical Lorentz force is that which when integrated over distance will supply the free-energy difference necessary to move the flux

Jan 1, 1968

By H. R. Gardner

THE wide variation in tension and compression properties' which exist between the a,ß and ? phases of plutonium indicate that a study of the impact properties would give a greater insight into the variables affecting the mechanical properties and formability of plutonium. In tension the a phase is quite brittle with elongations less than 1 pct. The ß phase at normal test speeds is unusually ductile; elongations up to 621 pct have been obtained. However, the ß phase is quite sensitive to strain rate; elongations decrease rapidly as strain rate is increased. The y and 6 phases are less ductile than the ß phase, with the 5 phase the more ductile of the two. Neither are very sensitive to strain rate. Considering the brittle nature of a Pu in tension and compression and the strain rate sensitivity of ß -phase Pu, both unnotched Charpy specimens and standard V-notched Charpy specimens were fabricated for testing. In addition, since iron in amounts greater than 500 ppm forms a Pu-PlgFe eutectic network which inhibits microcracking in as-cast plutonium,' it was decided to prepare impact specimens with low and high iron contents. Chemical analysis and density data for the impact specimens are presented in Table I. A total of 55 impact specimens, 32 unnotched and 23 with the standard Charpy V-notch were tested at temperatures from —45' to 330°C. The test results for both unnotched and notched specimens are illustrated in Fig. 1.

Jan 1, 1962

By K. G. Davis, P. Fryzuk

WEINBERG,' in an investigation of solute distributions along unidirectionally solidified rods of dilute silver in tin alloys, concluded that, for rods of 2 mm diameter or larger, a very high degree of convective mixing takes place in the melt ahead of the advancing interface. Suggested causes for this mixing were (1) thermal convection, (2) convective currents set up by changes in fluid density associated with concentration gradients, and (3) currents set up by changes in volume during freezing. Evidence was presented that causes (2) and (3) were not primarily responsible for solute mixing. Further, convective mixing took place in horizontal rods with temperature gradients as low as 6°C per cm, putting doubt on the importance of thermal convection. In the present work, convective mixing is examined in melts with known initial solute distributions. The absence of a moving solid-liquid interface eliminates convection caused by volume changes on solidification. In the first experiment, three silica tubes 2 mm in diameter and approximately 20 cm long were filled with an alloy of 100 ppm Ag in tin (99.999 pct purity), placed adjacent to one another in a horizontal furnace, and solidified from one end at 1 cm per hr. A110, a Y emitter, was used as tracer. A few centimeters at the start of the rod were left un-melted, to determine the initial concentration Go. After solidification was complete, one sample was removed. The hot furnace was then brought back to

Jan 1, 1965

THERE is at least one concrete indication that Soviet Russia's two most important iron ore producing centers are seriously depleted. While keeping in mind Russia's penchant for reverse propaganda, one piece of evidence indicates that Magnitugorsk in the southern Urals and Krivoi Rog in the Ukraine have been mined to a point where lower grade ores are being recovered. An article in Pravda, Soviet newspaper, by I. P. Bardin. a Russian metallurgist, says that ore presently mined must undergo an expensive enriching cycle before it can be used in blast furnaces. Com- pounding Russian metallurgical troubles is the low quality of coking coals. High ash and sulphur content typifies the coal Badin talks about. Coal from the Ukraine, Eastern Siberia, Kazakhstan, and the Far East requires extensive treatment before it can be used, according to the article in Pravda.

Jan 7, 1953

By W. White, C. S. Barrett, R. M. Mueller

THIS communication reports film-recorded low-energy (-100 kev) proton blocking patterns'-3 for hcp and wurtzite crystals. In particular the sequence of relative line intensities* (corresponding to planar blocking) of common hcp metals is compared with those of the wurtzite semiconductors CdS and CdSe. The results show that the sequence is characteristic of structure. For closely similar structures such as those of CdS and CdSe, differences of line intensity attributable to the difference in atomic number, 2, of the scattering centers may also be seen. The apparatus and techniques used in this work were identical with those reported previously in a study of cubic systems.3 All metals were given standard metal-lographic etches, and the semiconductors cleaved, immediately prior to introduction to the vacuum system. Fig. 1 shows the unit cell of the wurtzite structure, and the geometry used to obtain the [1120] and [0001] patterns of Fig. 2. The axial ratio, c/a, for all ma- terials of Fig. 2 is close to 1.63. The patterns are then directly comparable in linear dimensions inasmuch as they have been reproduced at the same overall magnification of the patterns. (Overall magnification is proportional to the product of film-to-target distance and printing magnification. Thus the 1/6-in.-diam beam passage hole in the center of the film need not appear of uniform size in the prints.) The patterns for a given orientation, though similar

Jan 1, 1970

By T. A. Rickard

Our Transactions contain two notable papers descriptive of the stamp-milling practice of the Black Hills and of Grass Valley, namely, the elaborate and complete treatise of Prof. H. 0. Hofman, on " Gold-Milling in the Black Hills,"" and the paper describing the North Star mill, by E. R. Abadie, its superintendent. Having visited and examined the stampmills of both localities, I venture to offer here such comment as more recent information or a different point of view has suggested.†

Jan 1, 1896

THE following employment items are made available to AIME members on a nonprofit basis by the Engineering Societies Personnel Service, Inc., operating in cooperation with the Four Founder Societies. Local offices of the Personnel Service are at 8 W. 40th St., New York 18; 100 Farnsworth Ave., Detroit; 57 Post St., Son Francisco; 84 E. Randolph St., Chicago 1. Applicants should address all mail to the proper key numbers in care of the New York office and include 6c in stamps for forwarding and returning application. The applicant agrees, if placed in a position by means of the Service, to pay the placement fee listed by the Service. AIME members may secure a weekly bulletin of positions available for $3.50 a quarter, $12 a year. MEN AVAILABLE Geologist-Petrographer. Experienced subsurface geology and petrographic rock and mineral identification. Desires position as either geologist or petrographer. M-682. Geologist, 36, married, employed. Nine years' experience geology connected with engineering, includes planning and supervising core drilling programs, study of stratigraphy and structure, special problems, report writing. Three years' teaching experience. Desires responsible position offering opportunity for advancement with progressive concern. Will travel part time. Available reasonable notice. M-683. Mining Executive with record of accomplishment organizing and directing efficient low cost mining and ore dressing operations available for position in the United States. Broad experience engineering, mechanized mining, flotation, safety, union labor relations and preparation of reports. Married. Employed; available upon reasonable notice. M-684.

Jan 1, 1952

By Vernon Taylor

CANADA'S oil production is obtained almost entirely from the Turner Valley gas and oil field, in the Province of Alberta. This field, about 30 miles southwest of the city of Calgary and approximately 115 miles north of the United States border, supplied 92 per cent of production in Canada during 1937. In 1938 considerable development took place in this field and total production for the year amounted to 6,688,716 bbl., an increase of 3,922,146 bbl. over the production in 1937, which increased the percentage of production to approximately 97 per cent of Canada's total. In the British Empire, Canada's production is thus comparable to that of Bahrein Island and Burma, each of which produced approxi-mately 7,800,000 bbl. in 1937, being second to Trinidad's production of 15,500,000 bbl. The total production of the British Empire in that year amounted to 2.07 per cent of the world's total. HISTORY Development of the Turner Valley field commenced in 1913, when a well was started near a gas seepage on the banks of the South Fork of Sheep River in the central part of the Valley. This well found small quantities of a light crude oil in beds of Upper Cretaceous age and pre-cipitated a wild boom in 1913-1914 which ended with the beginning of the Great War in 1914. A small amount of drilling was done in the years from 1914 to 1922 and a few wells found small crude-oil production in the upper sands. In 1922 a few wells were started, including the Royalite Oil Company's No. 4 well (R, Fig. 1), which became the discovery well of naphtha pro-duction from the Paleozoic limestone. In October 1924, this well was completed at a depth of 3740 ft., being approximately 300 ft, in the lime-stone, with an initial flow of 600 bbl. of 72° A.P.I. gravity naphtha and 20,000 M cu. ft. of gas per day. Intense activity was not started until the latter part of 1928, when the Okalta No. 1 well (Q, Fig. 1) was drilled, with an initial production of 500 bbl. of naphtha per day. This well was only 1 ¼ miles from Royalite No. 4, but it was approximately 1300 ft.

Jan 1, 1939

By Wesley G. Josephson

THE MINING PROPERTY of the Argonaut Mining Co., Jackson, Calif., is one of the oldest on the Mother Lode. A vein outcropping on a hill in this section could not long elude the eye of the forty-niner, so it was first discovered in 1850. From that time until 1893 the Pioneer mine, as it was then called, limped along under various poorly equipped and financed operators who tried tapping it by trenching and tunneling. Then the Argonaut Mining Co. took over the property and sank the present 65° inclined shaft in the hanging wall of the vein. The mine workings have now reached the 6000-ft. level, which is 5283 ft. vertically below the surface, or just 3 ft. over a mile. The total production of the mine is uncertain, because of lack of early records, but from 1893 to 1932 it is known to have produced in excess of $17,000,000.

Jan 1, 1932

By John Shelton

ONE of the heaviest burdens uselessly cast by our mineral land laws upon the holder of the title conveyed by a patent from the United States is due to the provision excepting known veins from land patented as placer. In many instances the expense of defending such titles from the assaults of the owners of lode locations made upon the theory that the veins so located were known to exist at the date of the placer application for patent has exceeded many times the value of the land in question. Neither the lapse of time, however long after the issuance of the patent nor repeated adjudications by the courts serve to quiet such titles or to prevent them from being questioned. In the passage of laws providing for the acquisition of title to the mineral lands of the United States, Congress provided that the title to known veins should not pass from the United States by a patent based upon a placer location. As construed by the courts, the law (Sec. 2333 R.S.U.S.) provides that the applicant for a patent upon a placer claim may, if any vein of sufficient value to justify the expenditure of money in its development is known by him to exist within the boundaries thereof, include in his patent application an application for patent upon the vein as a lode claim; and failure to do so is to be deemed a conclusive declaration that the applicant makes no claim to the vein nor to an area of surface ground extending for 25 ft. (7.6 m.) on each side of its middle or center. As to such vein and, such area of enclosing surface ground under the circumstances stated, the title remains in, the United States notwithstanding the issuance of a patent that purports to convey the entire surface of a described area and everything beneath it, excepting only the segments of veins the apices of which lie outside of such area. Such known veins with such area of enclosing surface ground are, of course, at any time, so long as they remain unlocated, subject to location and appropriation in the same manner as other veins upon the public domain. The history of the operation of this law in one district will serve to illustrate its effect generally throughout the mining regions of the United States. In the Butte district, the mineral that first attracted the atten-

Jan 8, 1919