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By W. B. Weeks, H. K. Shearer

The year 1937 brought to south Arkansas increased drilling activity and production. Oil production amounted to 12,159,440 bbl., an increase of 1,504,500 bbl., or 14.1 per cent over 1936. This was the largest production since 1931, and the first annual increase since 1925, when the deeper sands at Smackover were developed. There were 177 wells completed during the year, with 103 oil wells, 6 gas wells, and 68 dry holes, an increase of more than 100 per cent over 1936. Of the 56 wildcat wells drilled, 52 were dry and 4 produced oil. Two new fields, one important extension and three minor extensions were discovered. The trend toward deeper drilling is shown by the fact that 97 wells were more than 5000 ft. deep, including 80 over 6000 ft. and 13 over 7000 ft., although the depth record of 7973 ft., made in 1935, was not exceeded. Geological Section Deeper and more extensive drilling during the past few years, not only in south Arkansas but also in adjacent parts of north Louisiana and east Texas, has furnished much important geological information and has brought out some very unexpected facts in regard to structural and depositional conditions in the series of formations laid down in the interval between the end of the Pennsylvanian and early Cretaceous time. It is now evident that an important basin of salt deposition existed in the Arkansas-Louisiana-Texas area, but it is still an open question whether this salt basin was contemporaneous and continuous with the even larger Gulf Coast salt basin extending from Mississippi to Mexico. The accompanying columnar section (Fig. 1) shows the producing zones and names that have been applied to the several subsurface formations, most of which have no outcrop equivalents. This is for the convenience of readers unfamiliar with recent developments, but the correlations and nomenclature cannot yet be considered final. These formations will be discussed in more detail in various papers to be published in the near future.

Jan 1, 1938

By N. E. Maccallum

Almost half a century has passed since the Siemens brothers, after tedious and costly experiments, finally began the manufacture of open-hearth steel. The furnace of that time was very small, having a hearth-capacity of from 3 to 4 tons, and we can appreciate the wonderful development that has taken place in those 50 years by the knowledge that to-day furnaces of 50 times the original capacity are in operation. As the new steel process assumed importance, and furnaces began to grow in number and in size, a question arose, to which no satisfactory answer has ever been given, and that was: aWhat is the safe and economical limit of the open-hearth furnace ?" Various stopping-places have been suggested, and 20, 30, 40, and 50 tons have each been advocated, but all such arbitrary restrictions have been passed, and 60 tons would probably represent the average furnace, although in a few instances from 70 to 80 tons are regularly tapped into one ladle. The furnaces which are the subject of the present paper have gone far beyond even these limits, and since, in my opinion, they mark another step in the progress of open-hearth steel, they will be considered fairly and frankly, in order that those to whom the matter may be of interest may be able to judge and form their own conclusions. Short accounts of the work of these furnaces have appeared from time to time in various technical journals, of which the following is a brief résumé. These furnaces are the property of the Phoenix Iron Go., of Phœnixville, Pa., and their distinctive and important feature is, that they charge to twice the capacitl of one ladle, and tap simultaneously into two ladles, with a device for controlling the flow into either. In this way the capacity of the furnace is not limited, as formerly, but heats of any size within the capacity of two ladles may be charged.

Jan 1, 1913

By R. W. Parsons

This discussion concerns fitting an ellipse to angle, where the permeability k is measured for a series of plugs cut from varying angles in the horizontal plane. The conclusions and procedures given by Greenkorn, et al. are in no way affected by these comments, since the degree of anisotropy (ratio of maximum to minimum permeabilities) they found is generally quite close to one (see their Table A-1). However, since large anisotropies may arise, I feel that the comments should be made. Both Marcusl and Scheidegger2 have shown that there are two limiting expressions for the permeability of an unbounded anisotropic media. If the permeability is measured in the direction of the pressure gradient, the result is equivalent to the author's Eq. 11. This is the equation used to find kl1 and k22 from the experimental data. If, however, the permeability is measured in the direction of flow, then the resulting equation for the measured permeability is From these equations it follows that plots on angle will be ellipses. The principal axes will correspond with the major and minor permeability axes. The question arises as to what permeability is actually being measured on an anisotropic sample in the laboratory. An overall pressure gradient and a gross flow rate are determined and a permeability calculated by Darcy's law. The details of the macroscopic flow within the sample will be determined by the boundary conditions of the sample and the orientation and magnitude of the major and minor permeability axes. The situation is shown in Fig. 1 for the two-dimensional case. Using the method of conformal mapping, Marcusl has solved the problem of determining the overall apparent (or measured) permeability for this experiment for any condition of W-L ratios and orientation and magnitude of the principle permeability axes. For W-L ratios approaching zero, the streamlines are all forced by the boundary conditions to be in the direction of the measured permeability which is equal to kg. For W-L ratios approaching infinity, the effects of the no-flow bounds are negligible, and the pressure gradient and measured permeatility direction are parall;l. The streamlines are

Jan 1, 1965

By Robert Phelps

A STUDY of solid solutions has long been a source of interest because of the conditions -controlling their formation. X-ray investigations so far have been conducted with the idea that there were two types of solid solutions. In the first type, an atom of the solute was supposed to replace an atom of the solvent in the crystal lattice. In the second type, an atom of the solute was supposed to lie in one of the interstices between the atoms of the solvent. These pictures both require that the sizes of the atoms must play an important part in the process of solution. It is the purpose of the present investigation to study the mechanism of solid solution, using pure silver as the. solvent, and pure aluminum as the solute. X-ray measurements show that these elements have the same "shape" of atomic domains (they both crystallize as face-centered cubes) and that their atomic diameters differ by less than one per cent.1 The results of the present investigation point toward a chemical rather than a physical picture of the nature of solid solution, and make the older' pictures merely special cases of a more general picture. The new theory has the advantage, too, that it offers a rational explanation of certain phenomena which hitherto have been only interesting detached facts. The aluminum-silver system which was, chosen for this study has been studied by various methods by several workers. By means of thermal analysis Gautier2 and Petrenko3 have determined the phase diagram. Hansen4 studied the aluminum-rich alloys by means of thermal and microscopic analyses. , He showed that at high temperatures silver dissolved in aluminum to the extent of 47 per cent by weight at 5600 C. But this solubility decreased to 1 per cent at 200° C. Westgren and Bradley5made an extensive X-ray study of these alloys. They used the change in the lattice parameter of silver as a criterion of the solution

Jan 1, 1932

By W. H. Andrews

The constantly increasing consumption of Portland cement in the State makes the above subject of particular interest at this time. The increasing demand is due to the rapid settling of the country and the fact that new uses are being found frequently for the above named commercial article. The industry is one that is bound to grow as the population increases, and this being the case it may be well at this time to consider briefly the matter of the chemical and physical composition of proper raw materials. A cement mixture is one that contains approximately 75 per cent, carbonate of lime, 15 per cent. silica, and 5 to 7 per cent. alumina and iron oxides; the other elements being magnesium carbonate and mall quantities of the rarer elements generally associated with limestone deposits. It can be readily seen from the above composition that it is possible to build up this mixture from a number of different materials. First.—A rock high in carbonate of lime can be mixed with clay or shale in such proportions as to bring about the desired composition ; the chief difficulty in the building up of such a mixture is that it is hard to find a clay or shale in which the silica-alumina ratio lies between 4 to 1 and 3 to 1 and at the same time shows physical characteristics which will make certain its adaptability to the practical manufacture of Portland cement. Very often clays or shales are found which are right chemically but contain large quantities of grit or free silica. Such clays or shale must be ground to extreme fineness in the mixture in order to make the silica and alumina combine with the lime when the mixture is burned. On the other hand, clays or hales are often found that have the proper physical characteristics but in which the amount of alumina is too great. Second.—A mixture can be built up of different limestones some of which run above the 75 per cent. requirement and others below;

Jan 1, 1914

Lewis, B. LINDEMUTH, ?New York, N. Y.-I would like to confirm Dr. Howe's supposition that a process could be worked out for steel along similar lines. About 1 ½ years ago, F. D. Carney and myself were working on the elimination of columnar crystals which are particularly evident in nickel steel. We discussed rotation and varying speeds of rotation, but figured that with just rotation the steel would eventually catch-up to the motion of the mold and that the desired effect could not be obtained in that way, so we decided to alternate the direction of rotation. We rigged up in ordinary commercial turntable and on the same mounting attached a blast, furnace and mud gun, which is a simple steam cylinder, and mounted an 18-in. ingot mold on the turntable. The turntable had a stroke of about 10° to 12°, with stops at the ends. The steam cylinder would bang the table against the stops so that the stopping was so violent that it would tend to keep the metal in motion when the mold stopped and thus wash away any crystals that would form. We made quite a few interesting experiments; the results of which were that the columnar crystallization was entirely eliminated. At the same time we cast ingots in a similar mold, allowing the molds to remain stationary; these showed columnar crystals of from 2 to 4 in. in depth. The grain structure of the balance of the ingots, which were rotated, was very much finer than the grain structure of the ingots that were cast and allowed to cool slowly. The experiments were made on a 0.35 per cent. carbon nickel steel, which is probably more susceptible to columnar crystallization than any other. I think that the rolling properties and the forging properties of some alloy steels could be very much improved by a similar method, or some commercial method of casting ingots to eliminate this columnar crystallization.

Jan 5, 1919

By G. B. Craig, J. Rezek

The critical resolved shear stress of zone-refined zinc single crystals deformed in tension is found to increase with increasing amount of striation substructure. The increase in strength with numbers of striations can be accounted for by a dislocation pile-up mechanism. A somewhat different means of plotting stress-strain data is introduced which allows a more unambiguous choice of yield stress to be made. FEW systematic studies of the role played by mac-romosaic or striation-type substructure in the de- formation of high-purity metal single crystals grown from the melt have been reported. McGrath and Craig' found that striations increased the critical resolved shear stress of zone-refined aluminum crystals, postulating a dislocation blockage by the striations as the strengthening mechanism. Lauri-ente and Pond2 found that, as the etch pit density increased in aluminum crystals grown from the melt, the critical resolved shear stress also increased. Fleischer and Chalmers3 also found changes in the critical resolved shear stress of aluminum crystals grown from the melt at varying rates, but could not be certain whether an increase of strength with rate was due to a higher concentration of impurity in the gage length or to an increase in the number of small-angled boundaries. An early work by Hibbard4 indicated that copper crystals containing lineage boundaries were stronger than those free from this type of imperfection.

Jan 1, 1962

By H. W. Hitzrot

THE new 4800-ton fine-grinding plant at the Hollinger Consolidated Gold Mines property at Timmins, in the Porcupine district of northern Ontario, went into operation in November 1937, and represents the culmination of an experimental program. The plant is a moderately low rectangular building of hollow tile on a steel frame, large enough to house four 7 by 15-ft. ball mills, with a 12 by 27-ft. classifier beside each mill. At one end is space for the addi-tion of another mill and classifier or a mill and classifier for the regrinding of table concentrates. This regrinding is now done in the old grinding department of the main mill building. Also within the new building are the four 6-in. sand pumps for lifting the product from the low-dis-charge ball mills up to the classifier feed launders and the containers and appurtenances of a complete dust-collecting system. Together with the usual overhead crane, these constitute the major units of equipment within the new plant. The location is at the lower end of the main mill buildings toward the old tailings pond, now so neatly leveled off and sodded to rival the very best of our own W.P.A. projects. Close by the new grinding plant is a large dome-shaped structure-the new fine-ore bin designed and built by Mr. Longmore and the Hollinger milling and engineering staffs. There are four separate automatically loaded inclined belt conveyors leading up from the bottom of the bin to the grinding plant. Each belt is equipped with a recording weightometer, in the grinding building. The whole structure and the machinery within it give the impression of permanence and a carefully integrated design with close attention to details, giving the operators every advantage for consistently good work.

Jan 1, 1939

By C.F. Pascoe, H.J. Roast

The object of this investigation was to compare the arsenical antimony-lead alloy with some of the regular bearing-metal alloys. With this end in view, the following tests were made: 1. Chemical analyses to show the composition. 2. Thermal analyses. 3. Macroscopic examination of fractures. 4.Microscopic examination. 5. Tensile tests. 6. Crushing tests. 7. Scleroscope tests.' 8. Brinell tests, at temperatures from 80' to 400' F. Tests 3 to 8 were conducted on both sand-cast and chill-cast specimens. For the purposes of this paper the alloys have been numbered from 1 to 6; their composition is as follows: Lead. ' Antimony, Tin, CoppeR ARSEnic, NumBeR PeR CENT. PER CENT. PeR Cent. PeR CeNt. PeR Cent. 1 82.64 12.95 4.40 0.01 none 2 27.54 9.04 59.87 2.65 none I 3 none- 0.13 ------------1.47 4 82.95 16.85 none 0.20 none 5 83.78 15.35 none 0.05 0.82 6 0.15 7.87 . 84.13 7.85 none The analysis, in the case of the antimony, was made by solution in sul-furic acid and titrated with permanganate. For tin, the ferric-chloride method was used; for copper, the alkaline separations, and the thio-cyanate methods; for arsenic, volatilization of arsenic and titration with iodine. The lead, with the exception of alloy 6, was taken by difference. With the exception of No. 5, the alloys were taken as received from the manufacturer. About 40 lb, were melted in a graphite crucible and recast into small ingots to insure uniformity of composition; samples

Jan 1, 1923

By C. F. Pascoe, H. J. Roast

The object of this investigation was to compare the arsenical antimony-lead alloy with some of the regular bearing-metal alloys. With this end in view, the following tests were made: 1. Chemical analyses to show the composition. 2. Thermal analyses. 3. Macroscopic examination of fractures. 4.Microscopic examination. 5. Tensile tests. 6. Crushing tests. 7. Scleroscope tests.' 8. Brinell tests, at temperatures from 80' to 400' F. Tests 3 to 8 were conducted on both sand-cast and chill-cast specimens. For the purposes of this paper the alloys have been numbered from 1 to 6; their composition is as follows: Lead. ' Antimony, Tin, CoppeR ARSEnic, NumBeR PeR CENT. PER CENT. PeR Cent. PeR CeNt. PeR Cent. 1 82.64 12.95 4.40 0.01 none 2 27.54 9.04 59.87 2.65 none I 3 none- 0.13 ------------1.47 4 82.95 16.85 none 0.20 none 5 83.78 15.35 none 0.05 0.82 6 0.15 7.87 . 84.13 7.85 none The analysis, in the case of the antimony, was made by solution in sul-furic acid and titrated with permanganate. For tin, the ferric-chloride method was used; for copper, the alkaline separations, and the thio-cyanate methods; for arsenic, volatilization of arsenic and titration with iodine. The lead, with the exception of alloy 6, was taken by difference. With the exception of No. 5, the alloys were taken as received from the manufacturer. About 40 lb, were melted in a graphite crucible and recast into small ingots to insure uniformity of composition; samples

Jan 1, 1923

By M. L. Hammond, G. M. Bowers

Silicon dioxide films have been prepared on silicon wafers by the oxidation of SiH, near 400°C. Results previously reported by Goldsmith and Kern7 have been qualitatively corrobovated using a system of different geometry, and significantly greater deposition rates have been achieved. The deposition rate is independent of thickness and nearly independent of the O2/SiH, ratio over a wide range; however, the rate is strongly temperature-dependent. The structure of the deposit depends upon the cleanliness of the substrate, and the electrical field strength of the deposited oxide depends upon the nature of the electrodes. MULTILEVEL interconnects in integrated circuits using aluminum metallization require an insulator that can be deposited at low temperature. Because the A1-Si eutectic is only 577°C, the maximum deposition temperature must be below about 500°C to prevent reaction of the aluminum with the silicon and with other materials in the integrated circuit. Many methods of depositing insulating films of SiO, and other dielectrics have been reported'-6 but the technique described by Goldsmith and Kern7 offers the simplest method of preparing SiO, films. The technique involves the reaction of SiH, and 0, to form SiO, films in the 300" to 500°C temperature range. Previous work using this gas system has been reported8 and the initial development work at Philco Microelectronics was done at the East Coast R&D Laboratories. 9 This paper corroborates some of the results of Goldsmith and Kern,7 shows that much higher deposition rates can be obtained than previously reported, and presents some observations on the structure of deposited SiO, films. EXPERIMENTAL CONDITIONS Fig. 1 is a schematic drawing of the apparatus used in this study. It differs from that of Goldsmith and Kern in that 1) the gases are mixed before they enter the reaction chamber, 2) there is no fritted glass diffuser, and 3) the wafers are stationary during deposition. The control thermocouple was in a well located 0.06-in. from the substrate, and three gas supplies were used: 1 pct SiH4 in N 2, O 2, and N 2. Water vapor must be excluded from the plumbing to prevent the formation of colloidal SiO, and the SiH4 must be diluted with an inert gas because SiH4-0, mixtures are extremely flammable above about 4 pct SiH The wafer temperature was determined by attaching a thermocouple to a test wafer and the temperature was maintained to +5 C. The conditions used in this investigation are listed in Table I. The temperature range was chosen for compatibility with the A1-Si system. The volume ratio of 0, to SiH4 is the actual volume of 0, delivered to that of SiH4, taking into account the initial dilution of the SiH4. This ratio, which was used by Goldsmith and Kern,7 is a useful indicator of the experimental conditions. The active/inactive ratio is the ratio of the volume of active gases, SiH4 and O2, delivered to the volume of dilution gas. The active/inactive ratio is an important parameter to specify for deposition rate determinations since it determines the amounts of reactants that arrive at the sample per unit time. Fairly high dilution ratios were necessary to achieve uniform deposits of SiO,. Most of the process characterizations were performed on the polished (111) face of 3 to 5 ohm-cm, n-type silicon wafers which were 0.009 in. thick; but the data approximately apply to deposition of SiO, on thin films of aluminum. It is difficult to obtain accurate deposition rate data over aluminum films because of coarsening the aluminum surface during exposure to 300" to 400°C. The deposited SiO, film fol-

Jan 1, 1969

By Allen Garrison

IT is the purpose of this article to present. the results of an investiga-tion of certain clay and shale suspensions having viscosities that are materially influenced by fluid motion, and to discuss the bearing of these results, upon the choice of policy in the control of drilling fluids. A previous article described the design and the characteristics of an instru-ment adapted to measure the viscosity of plastic suspensions during continuous uniform motion and at a variety of speeds.1 It has long been recognized that the viscosity of a clay suspension depends on the past history of the fluid motion. Since an abundance of literature is available on this phenomenon,2 it is not necessary to describe it in more than general terms. It is usually observed that rapid motion reduces the viscosity of a clay suspension, and that some time is required for the viscosity to fall to its equilibrium value after the steady motion is started. On reducing the speed of motion to some lower value, the viscosity again rises, but it also requires some time to attain a steady viscosity value at the slower rate of motion. Thus clay suspensions are usually observed to be increasing in viscosity as time passes when the measurement has been immediately preceded by fluid motion that was more rapid than that employed in the measurement. And it is usually observed that the viscosity falls as time passes when the measurement has been preceded by more quiescent conditions. Reed,3 and Broughton and Hand4 have reported a condition of observa-tion of clay suspensions in which the viscosity was observed to fall during the first few moments of steady motion, and rise thereafter. The characteristics of the new instrument are particularly well adapted to studies of this kind. With it we have been able to observe all of the phenomena described above, and it is important to understand their nature because they all occur at some time during normal drill-

Jan 1, 1939

By J. T. Hayward

Studies of the forces and conditions governing the recovery of petroleum from natural reservoirs indicate that a low gas-oil ratio increases ultimate recovery, retards the encroachment of water and tends to reduce lifting costs. Methods for controlling and reducing gas-oil ratios in producing wells consequently have been given considerable attention during the past few years. However, during this same period, the production from wells in nearly all fields has been fixed by proration agreements and it is the opinion of the writer that where a well is required to produce steadily at a predetermined rate, less than its "potential" or maximum capacity, the gas-oil ratio will depend only upon the rate of production, and will be independent of the method of production and of the design of equipment in the well. If no change in the rate of production is contemplated, efforts directed to improving the gas-oil ratio by altering the diameter of the flow string, changing the position of the choke, assisting the flow with gas-lift or pump, etc., will be unsuccessful. This viewpoint is not new. It was presented by H. N. Marsh and B. H. Robinson in 1929,' but it has not been generally accepted. Although engineers believe that the rate of withdrawal and not the equip ment used governs the water-oil ratio, a similar opinion regarding the gas-oil ratio is not so commonly admitted. The rates of flow of oil and gas into the base of an oil well depend upon the following conditions: 1. The characterist-ics of the oil and gas. 2. The characteristics of the underground reservoir. 3. Temperature and pressure conditions in the reservoir. 4. The back-pressure held against the face of the sand. In operating a well, the only one of these conditions over which control may be exercised through operating procedure and the use of equipment above the sand is the back-pressure at the face of the sand. Strictly speaking, the back-pressure varies over the face of the sand, owing

Jan 1, 1932

By R. W. Raymond

The death of Professor Blake removes the oldest of American economic geologists and mining engineers, and deprives this Institute of one of its earliest and most illustrious members. To many of us it brings a personal loss also, the loss of a friend. William Phipps Blake was born June 21, 1826, in New York City. His father, Elihu Blake, was a surgeon-dentist of eminence, a direct descendant of William -Blake, who settled in the Massachusetts Bay Colony about 1630. He was prs pared for college at private schools in New York, and entered the Sheffield School of Yale, where he was graduated as Ph.B. in the chemical course, class of 1852, the first graduating-class of the institution. In the same year he became chemist and mineralogist of the New Jersey Zinc Co., and chemist of chemical works at Baltimore, Md. In 1853, he started the Department of Mineralogy of the World's Fair at New York City. In 1854, 1855 and 1856, he was mineralogist and geologist of the United States Pacific Railroad Surveys of Willianlson, Pope, and Whipple, and for the War Department at

Jan 1, 1911

Crushed limestone is now being "de-dusted" at the Warner Co. plant in Bellefonte, Pa., by a new high-efficiency classifier utilizing aerodynamic principles not previously employed in classifiers. Crushed limestone for certain glass industry requirements must not have more than 10 pct fines in the overall aggregate, and it is the function of the new-type classifier to separate these fines from the coarse material. During the development of this classifier by the Buell Engineering Co. of New York, it was found to have possible applications for separating pulverized coal, sintered metals, ores, mineral flours, and fillers, among other items. Limestone from Warner's deep mine is initially crushed and particles larger than 3/8-in. mesh are burned in kilns to provide calcium oxide for the chemical industry. The 3/8-in. screenings are dried and crushed to -16 mesh for use by the glass industry. For those applications requiring a minimum of fines, no more than 10 pct -100 mesh material is allowable in the end product. Hence the need for high-efficiency separation.

Jan 11, 1960

By M. M. Wong, D. E. Couch, G. M. Martinez

The Bureau of Mines electrowon hafnium metal with an average oxygen content of' 150 ppm at 700°C from an electrolyte containing 27 wt pct LiCl, 62 wt pct RbCl, and 11 wt pct HfC14. The average anode and cathode current efficiencies were 90 pct at anode and initial cathode current densities of 86 amp per sq ft. Haf-nium metal with an average oxygen content of 440 ppm was electrowon at 800oC from an electrolyte containing 90 wt pct KC1 and 10 wt pct HfCl4. The average anode and cathode current efficiencies were similar to those obtained in the LiCL-RbCl-HfCl, electrolyte. The chlorine gas given off at the graphite anode was vented through either a silica or a graphite tube to prevent cell corrosion. THE current method for the commercial production of high-purity hafnium is the thermal decomposition of Hfl4.1 The iodide method is not adaptable to continuous process techniques. Nettle, Hiegel, and Baker2 studied the electrorefining of hafnium from hafnium sponge containing 800 ppm oxygen. They failed to obtain hafnium with 600 ppm oxygen in their initial deposits and obtained AEC specification for oxygen only after 75 pct of the soluble hafnium had been removed from the electrolyte. Calculations using their data indicated this was approximately 4 lb of hafnium. The electrolyte was then used to produce approximately 3 lb of hafnium with a low oxygen content. However, no data are shown concerning the amount of anode material initially used or what percent of it was dissolved, therefore, results are not suitable for evaluation of a continuous operation. In general, it was not possible to consistently obtain low oxygen content metal with the electrolytes described by Nettle, Hiegel, and Baker. Wong, Hiegel, and Martinez3 investigated the electrorefining process for hafnium and showed that even by strict control of electrolyte composition only relatively low oxygen reduction could be obtained. The oxygen contained in the hafnium anode material tended to transfer to the cathode deposit and only a limited purification was possible. Both the "iodide" and the "electrorefining" processes depend upon hafnium sponge as a starting material. The sponge is normally produced by magnesium reduction of HfC14 ' and does not meet AEC specifications for hafnium metal. Since only 30 pct of the anode feed could be utilized3 in the electrorefining cells, the Bureau of Mines developed an electrowinning process. HfC14 was used as the feed material for the electro-winning process described in this report. Many of the electrolytes used in the electrorefining studies3 ap- peared to be suitable carrier-electrolytes for HfC14. However, in the initial studies on electrowinning, it was desirable to use electrolytes that had low solidus temperatures and could be operated over a wide temperature range to investigate parameters of the process. Therefore, electrolytes containing LiC1, NaC1, KC1, RbC1, CsC1, and HfC14, in various combinations were explored. EQUIPMENT Chlorinator. Hafnium carbide was chlorinated to produce HfC14 in the batch-type chlorination shown in Fig. 1. Chlorination temperatures were measured with a thermocouple placed in the center of the HfC charge. A flow meter was used to monitor the helium and chlorine. The exhaust side of the silica chlorina-tor tube was equipped with a flask for collecting organic material released during the initial heating of the HfC. The temperature of an internal heater, which extended from the HfC14 condensing flask to the hot end of the chlorinator, was adjusted to prevent the HfC14 from condensing before entering the collection flask. Helium and excess chlorine were exhausted through the lid of the collection flask to an aqueous NaOH solution. Sublimer. Initial studies were conducted using a sublimer, Fig. 2, made by placing a 13/8-in. OD nickel thimble 11 in. long, inside a 11/2-in. ID nickel bell 12 in. long, and locking it in place. This unit was loaded with HfC14 and partially immersed in the molten electrolyte for sublimation directly into the electrolyte. In another sublimer shown in Fig. 3, the HfC14 was contained in a "resin reaction flask". Quartz wool, previously heated to 600aC, secured between two nickel wire screens, was placed just above the HfC14 powder. The lid contained a vacuum outlet, a gage, an argon inlet, and an air-cooled pipe for condensing the HfC14. This sublimer was evacuated and heated. The sublimation temperature was not critical and the sublimer operated satisfactorily at all temperatures between 250" and 350°C. Electrolytic Cell. The electrolyte chamber, Fig. 4, was made of mild steel 8-in. schedule 20 pipe, 30 in. long. The exterior was metallized with a Ni-Cr alloy. The electrolytes were contained in a 16 gage nickel or iron liner with a nickel heat shield on top. The cell was heated by a resistance furnace. A 21/2-in. ID by 25 in. long air lock was connected to one port of a two-port cell cover assembly through a slide valve. The cover assembly of the air lock was electrically insulated from the cell and was equipped with a rubber sleeve that provided for the passage of the cathode lead. This allowed the cathode deposits to be removed and a new nickel cathode to be introduced without allowing air to enter the cell. A tube-rod assembly was bolted to the other port on the cell cover assembly and was sealed by a packing seal. The tube-rod assembly consists of a graphite

Jan 1, 1970

By Arthur F. Taggart

The following conclusions on the work of the Hardinge mill are based on data furnished to the writer by the Hardinge Conical Mill Co. in the form of the mesh cards hereto appended. Energy units (E. U.) and relative mechanical efficiencies (R. M. E.) are computed by the "volume method" of Stadler.' Screen apertures used are the average apertures of testing screeps of the meshes given. i . Card 122. June 28, 1912. Vipond Porcupine Mines Co., Ltd., Schumacher, Ont., Canada. Ore from mill bin. Gangue, quartz and basalt. 4.5 ft. by 13 in. ball mill, Capacity, 48 tons per 24 hr. Charge, 4,000 lb. balls. Speed, 33 rev. per minute. Horsepower, 15 to 17. Water, 100 per cent. by weight. (50 per cent. ?) Product deslimed and oversise reground in pebble mill, see Card 113. Feed to mill through 2-in. mesh. Mesh Feed, Per Cent. Discharge, Per Cent.. + 1in. 5.50 ....... + 3/4. 28.00 + in. 30.00 ...... + 1/4in. 19.72 ....... + 10 10.87 2.10 + 20 2.42 8.00 -20 3.51 .....,. + 40 ....... 22.68 + 60 ...___ 10.50 4-80 ....... 11.80 + 100 ....... 3.90 -100 ....... 40.15

Jan 1, 1916

By A. B. Tanner

The effects of radon in drillholes on gamma-ray logs have been described by L. S. Hilpert and C. M. Bunker1 Since these effects may cause drastic error in the evaluation of uranium deposits, it is useful to know the conditions under which significant amounts of radon tend to accumulate in drillholes. In the studies described here, atmospheric conditions were found to dominate in the control of the behavior of radon in drillholes in the vicinity of a uranium orebody. The site of the investigation was in McKinley County, New Mexico, about 12 miles north of Grants. Drillholes of 4 1/4-in. diam, on 25-ft and 100-ft centers, penetrate ore in dry rock at a depth of about 100 ft. A geologic log of the drillhole of primary interest is shown in Fig. 1. Gamma-ray logs revealed three zones of ore-grade mineralization in the Todilto limestone. A 6-ft zone, the lowest of the three, assayed 0.20 pct U3O8 by chemical analysis. The limestone ores in this area contain disseminated uraninite and some yellow and orange secondary minerals. Only radon"", a member of the uranium'" series, was measured in this investigation. Radon is one of the chemically inert noble gases and is radioactive by alpha particle emission with a half life of about four days. In this discussion, amounts of radon are expressed in microcuries (1 microcurie equals 37,-000 disintegrations per sec) and concentrations of radon are expressed in microcuries per liter of drillhole air. Samples of air were obtained by lowering a sampling device (Fig. 2) into a drillhole and actuating the device at the desired depth. It was then raised to the surface and the sample was transferred to a storage tube. Within two days the sample was transferred to an ionization chamber, and the activ- ity of radon and its short-lived daughter products was measured at radioactive equilibrium with a vibrating-reed electrometer. The measurements were corrected back to the time of collection and involve errors estimated generally not to exceed + 5 pct to —15 pct. Radon Behavior in a Covered Hole: Fig. 3, a typical log of radon concentration vs depth in the covered drillhole, was made by using values of radon concentration at discrete depths. Continuous logs of alpha-particle radiation in the drillholes showed that such radon logs depict the continuous variation of radon concentration with depth quite accurately. Three features of radon logs were noted: 1) maximum

Jan 1, 1960

By Hans W. Schreiber, David W. Neuhaus

INTRODUCTION The Sunshine Mining Company's 16-to-1 silver deposit and mine project are located 384 kilometers (240 miles) southeast of Reno and 360 kilometers (225 miles northwest of Las Vegas, near Silver Peak in Esmeralda County, Nevada, at an elevation of about 2,300 meters (7,000 feet). The deposit was being developed, in 1980, with an anticipated mining and milling rate of 150,000 tons per year (500 tons per day). Mining is by underground, blast-hole open stoping with rubber-tire haul-age out of the mine to a straight cyanide plant about 5.5 kilometers (3.5 miles) from the mine. The product is a gold-silver dore which may be further refined at Sunshine's new refinery in Kellogg, Idaho. The cash required for investment was obtained through the sale of $25 million worth of 6 l/2h silver-indexed bonds. Some $15.0 million were directed toward development of the 16-to-1 Mine. These bonds, which were underwritten by Drexel Burnham Lambert of Chicago in April of 1980, are redeemable on or after April 15, 1985 or payable at maturity on April 15, 1995 at the greater of either $1,000 or the market price of 50 ounces of silver. Behre Dolbear acknowledges the kindness of the Sunshine Mining Company (Sunshine) for allowing the presentation of the subject material for this Case Study. APPLICABILITY AS CASE STUDY Reasons for Choosing 16-to-1 The reasons for choosing the 16-to-1 Mine as a case study follow: 1. The project is simple and compact. 2. The mine is small -- thus relevant to other contemplated precious metal operaions in the western states. 3. The areas of risk are readily identifiable. 4. A change to project financing was under consideration. 5. A substantial decline in the price of silver was experienced during development. 6. Behre Dolbear undertook one of the first feasibility studies of The 16-to-1 and thus has some familiarity with the project. Historical Summary The following history serves as a setting: 1. Late 1920s -- minor "production"(?) via shallow pitting. 2. Mid-1930s -- neighboring Nivlok Mine successfully put into production. 3. Late 1950s (?) -- Callahan Mining Company acquired rights and drilled -- results inconclusive; Callahan turned property back to Arthur Baker, who had originally interested Callahan in 16-to-1 on the basis of its similarity with Nivlok Mine.

Jan 1, 1985

By Perry Olcott

The Texas Gulf Coast had a rather disappointing year in the type of oil fields found. Although 17 fields were found in the area during the year, as against 21 fields in 1938, no field of major proportion was discovered. Of these 17 fields, 11 were oil fields, 4 were gas and distillate fields, and 2 were gas fields. The wildcat activity for the year resulted in about 400 dry holes, although probably 10 per cent of these were edge wells close to proved areas. During the year, 1455 oil and gas wells were completed as compared to 1637 wells in 1938, a decrease of 11 per cent. Production for the Texas Gulf Coast area for the year was 100,253,937 bbl. as against 92,530,467 bbl. produced in 1938, an increase of 8 per cent. The daily average production was 274,668 bbl. for the 365 days in the year, although only 252 producing days were allowed by the Railroad Commission; that is, 69 per cent of the time as compared to 71 days shut in for 80 per cent of the time producing in 1938. The total number of oil and distillate wells producing at the end of 1939 was 9495 as against 8451 at the end of 1938—an increase of 1044 wells, or 12 per cent. Of these wells, 6547 were flowing and 2948 pumping, or 69 per cent flowing. At the end of the previous year, 66 per cent of the wells were flowing. New Fields Angleton, Brazoria County.—The Angleton field was discovered by the completion of Glen McCarthy's No. 1 Carr in October for an initial production of 180 bbl. a day of 50" gravity oil through 11/64-in. choke with 3400 Ib. on tubing. The field is 1½ miles east of the town of Anchor. The discovery undoubtedly can be credited to the reflection seismograph, since several companies worked the area from 1933 onward with this type of exploration. The principal block was taken by the Humble company in 1934. Two deep holes by Humble revealed the presence of structure, although both were dry. The Humble and Sun companies later contributed money and acreage toward the drilling of the discovery well. The production is from a sand in the Frio, about 1700 ft.

Jan 1, 1940