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By Frank J. Wiebelt

The Mohawk lead-zinc mining in San Bernardino County, Calif., was examined by D. W. Butnor, an engineer or the Bureau of Mines, at the request of Dunton, Ray, and Greenwood, leaseholders. Current operations were on a marginal economic basis, and government aid was sought in an endeavor to outline ore reserves so that production might be maintained.

Jan 1, 1949

By H. H. Kaveler

Education is for the purpose of developing citizenship, and, if it is pursued for the additional purpose of preparing for a professional career, such as engineering, it is also directed to developing a knowledge of essential science, aptitude for the application of science to practical situations, and a knowledge of the industrial art in which the engineer will be engaged. The process of education required for engineering must of necessity extend beyond the classroom into industry. For that reason, the education of engineers should be divided as between the university and industry. Specialization in engineering should logically come as a result of experience in an industry. The student cannot take the time in a university, and, the university cannot teach the skills required to develop a specialist without sacrifice to the more essential broad purposes of formal education. In addition to talent in science, aptitude in the application of scientific fact, and knowledge of the industrial art, the engineer should possess certain personal qualities which are helpful in the pursuit of a professional career. Those personal qualities are: the ability to work as a partner in an enterprise, the ability to do jobs in a way whereby job performance is a means of gaining experience and increased responsibility, the capacity to write and speak in an understandable manner, and, a Proper regard for the "significance of answers." These pcrsOnal qualities may be of almost equal importance to acabemic accomplishments in the field of science. Development of such personal qualities are an essential part of the student's training in the university and in industry. They can be developed effectively through the leadership of instructors. Compulsory Education Nature played a mean trick On the human race when the evolutionary Process failed to develop in the individual a capacity to inherit knowledge. Were knowledge transmissible in a cumulative manner from generation to generation, mankind would be by inheritance wise beyond measure within a few generations. Then there would be little if any need for a "system of education." As matters stand, however, all must suffer the burden of starting life at the "zero " level of learning from which station each rises depending upon individual capacity to assimilate knowledge left of record by our predecessors and the individual effort exerted to compensate for Nature's failure to endow the offspring with intelligence. In the United States some degree of education is generally regarded as essential and necessary. Therefore, all citizens are subjected by law to an educational process covering the primary school age from six to sixteen years. Beyond the schooling required by law, many attend secondary schools, and beyond that, schools of higher learning. Our standard of living is at a level that permits an increasingly large fraction of the population the opportunity to go through all of the formal educational process. As a result, education in the colleges and universities has almost reached a mass production level. In spite of the high

Jan 1, 1949

By R. P. Heuer, Paul M. Tyler

THE literature on refractories, although fairly extensive, is so scattered through books and periodicals as to be difficult of access to the general reader and most of the individual papers serve merely to illuminate some particular phase of the industry. Two general treatises by American authors8.16 are available, also the somewhat older works by a well-known British authority, 12,13 but these make their appeal to the technically minded ceramic engineer. Another small group of publications deals with the use of refractories, mainly in the iron and steel industry.1, 3,5,6,11,15 Raw materials utilized by the refractories industry have been covered by sundry books and articles. For the relatively nontechnical reader and economist, however, there appears to be no single review that purports to describe the industry as a whole. Furnace linings and other products that are classed as "refractories" are designed primarily to withstand high temperatures but this important property is by no means the only requirement; a suitable refractory material must likewise withstand slagging (chemical' action), abrasion (physical wear), and spalling, as well as the various other stresses and physical phenomena induced by heat, of which softening or incipient melting is only one phase. Nevertheless, subject to these highly practical considerations, the definition of a refractory material is based upon temperature resistance. Broadly speaking, any material that shows obvious signs of fusion after being heated slowly to 1500°C (2732°F) cannot be classified as a refractory material. The characteristic properties and requirements of refractory materials are conveniently summarized in Fig 1, prepared on the American Refractories Institute Fellowship at Mellon Institute, Pittsburgh, Pennsylvania. Most of the factors of service and properties of refractories given in this chart are interdependent and are greatly affected in degree by the functions of temperature and time. The factors in the chart are believed to cover the commoner questions.

Jan 1, 1949

By Wilder D. Foster

In the method used in the Health Branch of the Bureau of Mines for petro-graphic identification of the minerals in a rock, the sample is crushed, ground to a fine powder in a mortar, the powder is put on a slide, a drop of index oil and a cover slip are added, and the slide is ready for examination. The rock should be ground fine enough so that most of the particles consist of only one mineral, otherwise identification is difficult. Finally, the amounts of the minerals present in the sample are estimated to the nearest 5 or 10 percent. When quartz grains are mixed with some claylike minerals) of which by far the most common example is quartz and kaolinite in a shale, grinding in a mortar does not always separate the quartz from the kaolinite; instead, the quartz grains become coated with the kaolinite and are not visible, even after careful search. Talc acts Similarly, but muscovite and pyrophyllite do not. In evaluating the possible silicosis hazard of breathing dust from a shale, it is essential to be able to see and identify all of the quartz grains, as the other minerals present are relatively innocuous.

Jan 1, 1949

By Sol Weller

The Fischer-Tropsch synthesis consists of the formation of long-chain hydrocarbons by passage of carbon monoxide-hydrogen mixtures over metal catalysts, usually based on iron, cobalt, nickel, or ruthenium, at temperatures in the range 180°-300° C., and at pressures of 1-15 atmospheres. Although the reaction has been known and studied for more than 20 years, the mechanism by which it occurs is still poorly understood. One approach to understanding is to consider the effect upon the course of the synthesis of variations in each of the important operating variables. Consideration of the experimental data pertaining to these variables may suggest an over-all picture describing the synthesis - a picture which, in turn, would have to be consistent with all the known facts. The first part of this paper will be concerned with such a consideration of operating variables; the second portion will discuss recent work pertaining to the role of metal carbides as intermediates in the synthesis.

Jan 1, 1949

By J. E. Hawley

This paper constitutes a report from the Committee on Geological Research to the Geology Division of the Institute. Two years have elapsed since a formal report was made containing several resolutions aimed at assisting geological research, a review of research equipment available, a summary of research projects suggested for consideration, and a list of research then in progress (see July, 1947, Bulletin, pp. 351-370). At this time we may note what action has been taken on the various resotions and suggestions of the Committee, indicate the more important accomplishments of independent investigators, and present a summary of the rather imposing volume and variety of research currently being carried on throughout the country. I.-Committee Resolutions and Suggestions 1.-A National Advisory Committee on Research in the Geological Sciences The original resolution adopted on the setting up of this Committee was approved with despatch by Council and was forwarded to the Minister of Mines and Resources. Due to a reorganization in the Department and possibly other reasons, no action on this important matter has yet been taken, but we are assured that some time this year such a Committee will be established by the Department of Mines and Resources. Unquestionably, it will give a fresh impetus to research in the geological sciences. When the noteworthy progress made by the research committees on Geophysics and on Soil and Snow Mechanics, established by the National Research Council, is considered, it is indeed regrettable that the Department of Mines and Resources has not acted more decisively in this matter.

Jan 1, 1949

By Edward Sampson, Allan B. Griggs

Surveying of many holes drilled by the U. S. Bureau of Mines in the Metaline district has shown surprising deviations. The holes start in the Ledbetter slate (Ordovician) and pass into the underlying gently dipping Metaline limestone (Cambrian) at varying depths, locally in excess of 1000 it. All holes start vertical, but one had deflected as much as 35° at a depth of only 300 it. One hole was found to be deflected 70' at a depth of 1000 ft. These deviations were not indicated to the drillers by any action of the rods or machines. Analysis of the survey data in the light of the observed geology indicates that the holes deviate most in the Ledbetter slate and scarcely at all in the Metaline limestone. The upper part of the "limestone'" in most holes is a massive rock strongly altered by hydrothermal action and essentially homogeneous. The slate is only obscurely bedded but has a cleavage, varying from slight to strong, which is unrelated to bedding. Drill holes have deflected to become nearly perpendicular to the cleavage. Several plans and cross sections are submitted showing the behavior of various holes. Introduction The Metaline district of northeastern Washington has received much attention recently and has promise of becoming even more important as a source of zinc than at present. Exploration has been conducted largely by deep diamond drilling, and in the course of this work it was found that holes became seriously deflected. This paper deals with the nature and causes of these deflections. The district lies along the Pend Oreille River in the northeastern corner of Washington, about loo miles north of Spokane, 9 miles from British Columbia, and 15 miles from Idaho. Three mines are now in operation and for a number of years have furnished a considerable production of zinc and lead. The ore contains zinc and lead in a ratio of about 31/2 to I, and occurs in the upper part of the Metaline limestone of Cambrian age, the upper member of which, where unaltered, is a rather pure limestone. This is overlain by Ledbetter slate of Ordovician age. Ore has formed by replacement of limestone, commonly 100 to 200 ft. below the slate, in areas of gentle dip, resulting in extensive tabular ore bodies. In and near ore, limestone has been intensely altered to granular dolomite and fine-grained quartz, which, where it predominates, forms "jasperoid." As part of their war program, the Geological survey and Bureau of Mines of the U. S. Department of Interior have been cooperating in an investigation of the district. The exploration by the Bureau of Mines in 1943 and 1944 was conducted largely by deep diamond drilling in which as much as 1000 ft. or more of Ledbetter slate was penetrated before the ore-bearing Metalin-2 limestone was reached. During the course of this drilling it was found that holes were seriously deflected while traversing the Ledbetter slate.

Jan 1, 1949

By J. A. Herdlick

The Star mine, near Neihart, Cascade County, Mont., has been in continuous operation since the construction of a 50-ton bulk flotation mill in 1939. The mine was examined by G. N. Bennett, an engineer of the Bureau of Mines, in November 1942. At that time the life of the operation appeared to be limited and a program of crosscutting and core drilling were recommended. The program had as its objective the investigation of a promising undeveloped area lying west of the Star vein and, if possible, the development of enough reserves in this area to insure continuous operation during the war emergency. Development of additional reserves would then justify necessary changes in the mill in order to eliminate the heavy penalties imposed for excess zinc in the bulk concentrates. The Bureau of Mines work began in February 1944 and was completed in September 1944. The project was started by Wilder R. Brinton and continued by Thomas W. Oster, mining engineers in the Bureau's Montana district office. Beneficiation tests on are and concentrates were made after completion of the underground work. This report presents the factual data obtained during all phases of the Bureau's investigation.

Jan 1, 1949

By T. N. McVay, E. E. Creitz

Rather large amounts of titanium minerals and some zircon and monazite are being recovered from dune sands about I. miles west of Jacksonville Beach, Fla. The Mining Branch of the Bureau of Mines, Southern Experiment station, has been interested in developing additional large deposits of similar sands in other areas of Florida. The results of a field study have been published1 concerning the sands occurring on Trail Ridge which runs north and south about 30 miles southwest of Jacksonville. This investigation was undertaken in order to identify the opaque titanium minerals occurring in Trail Ridge and because of the economic importance of Florida titanium minerals. Nature of the Problem The minerals present in the heavy fractions (sp gr > 2.94) of the sands are principally opaque minerals; staurolite, zircon, sillimanite, tourmaline, kyanite, rutile, a small amount of corundum, traces of the zinc spinel gahnite and garnet. Epidote, monazite, hornblende and ti-tanite are present in other dune sands but these minerals were not noted in the samples collected on Trail Ridge. All of the minerals except those which are opaque can be readily identified by the usual petrographic methods. However, Opaque minerals cannot be examined satisfactorily by transmitted light. Polished sections of the opaque-mineral grains were examined but these sections did not furnish useful information. Consequently, it was necessary to use means other than the usual petrographic methods to identify them. Previous Investigations of Heavy Minerals in Florida Sands Martens2 has described the heavy minerals in the Florida beach sands and has classified the opaque minerals as ilmenite with minor amounts of leucoxene. Miller3 studied a number of sands collected by Ross and Mertie in Florida. He states that the material from the Florida beach and dune sands that commonly has been called ilmenite has essentially the chemical composition of the material that has been called arizonite.4 The x ray diffraction patterns of several samples indicated that the supposed ilmenite is essentially amorphous, with only weak lines corresponding to ilmenite, and hence the material is unlike the type of arizonite from Arizona. Opaque Titanium Minerals Rutile is essentially titanium dioxide. However, as pointed out by Dana,5 important amounts of Fe+2 and Fe+3 as well as Cb and Ta are reported in some analyses.

Jan 1, 1949

By J. W. Galpin, V. L. Minear, W. D. Owsley, F. C. Sturges, B. H. Mott, R. H. Allen, W. W. Weigel, R. E. Moeller

By definition the word "grout" means a thin mortar, or a kind of plaster or cement, and "grouting" means to fill up or finish with grout. The words "cement," "plaster" and "mortar" mean a substance that is used in a soft state which subsequently hardens. Thus, grouting is the filling of void space with a substance that hardens. Construction cements are the most common substances used, either by themselves or in mixtures, but the term grouting is applied quite correctly when other substances such as plastics and certain chemicals are used. Also, the use of the term grouting to cover the filling of voids with materials that do not actually become hard, such as the flotation tailings used in grouting in the southeast Missouri lead district, should be considered correct, as some stiffening does take place and, anyway, it is a better descriptive term than any substitute. Engineers are interested in grouting because some of the materials with which they must work contain voids, and certain conditions can be improved if these voids can be filled with something solid and permanent. Grouting is done to accomplish several purposes: I. To stop the passage of fluids and gases, 2. To cement materials together to make them stronger, and 3. To prevent consolidation of materials by filling void space with something solid as a replacement for the air and water that could be forced out under load. The construction industry uses grouting extensively for all three purposes. Grouting is used to stop water percolation under and around dams. It is used to control water flow in tunnel driving and in shaft sinking. It is used to improve foundation conditions under civil engineering structures by permanently filling void space and thereby reducing settlement, or by cementing broken rock together and increasing its supporting strength. The oil and gas industry does a lot of grouting, primarily to stop the passage of gases and fluids. The search for oil at increasingly greater depths has meant greater investment per well, and the oil industry has spent large sums on development of improved drilling methods. This

Jan 1, 1949

By W. N. Lacey, B. H. Sage, J. S. Billheimer

A restricted ternary system made up of n-pentane, tetralin, and a purified bitumen was investigated at 70, 160, and 220 °F. Most of the experimental observations were at atmospheric pressure or at 200 psi." However, some experimental measurements were carried out at a pressure of approximately 8000 psi. It was found that the purified bitumen was precipitated from its solution or dispersion in tetralin by the addition of n-pentane and that the separation occurred at lower weight fractions of n-pentane at the lower temperatures. The bitumen-tetralin solutions show some colloidal characteristics at temperatures below 160 °F when near compositions at which the bitumen separates as a solid phase. At states remote from the phase boundaries and at temperatures above 160 °F these characteristics become less evident. Under these latter circumstances the mixtures tend to follow the behavior of true solutions, particularly in regard to the approach to heterogeneous equilibrium. An increase in pressure appears to increase the solubility of bitumen in tet-ralin-n-pentane solutions. This effect is more pronounced at temperatures above 160 °F than at lower temperatures. INTRODUCTION Asphaltic phases of plastic or solid nature have appeared in numerous instances during the recovery of petroleum from underground reservoirs. Such depositions occurring underground appear to have caused adverse production histories for particular wells or zones. Because of this field experience, it is desirable to understand the factors which influence the formation or separation of the asphaltic phases from petroleum. The problem is unusually complex because the number of true components involved is very large and the details of the phase behavior encountered are difficult to ascertain experimentally. The literature relating to asphalts, asphaltines, and bitumen is voluminous and widespread.' Only those references which are directly pertinent to the work at hand are cited. The separation of an asphaltic phase, hereinafter called bitumen? from naturally occurring hydrocarbon mixtures has been the subject of several investigations.2'3'4'5'6 It has been found that as many as four phases4 may be produced from a crude oil by the solution of a natural gas and propane at a pressure of 1500 psi and a temperature of 70 °F. The separation of bitumen from such naturally occurring mixtures results in at least one liquid phase which is substantially free of high molecular weight components.³ The influence of the solution of lighter hydrocarbons on the separation of bitumen from a Santa Fe Springs crude oil has been investigated. The results indicate that in the case of the methane-crude oil system, the quantity of plastic or solid phase separated reaches a maximum between 0.14 and 0.19 weight fraction methane and then decreases until negligible at higher weight fractions of methane. Similiar behavior was encountered in the case of mixtures of ethane and crude oil. The decrease in the quantity of the solid phase with an increase in the weight fraction of the lighter component appears to result from the formation of an additional liquid phase6 in which the bitumen is relatively soluble. The formation of this additional phase probably occurs at a weight fraction of methane close to that at which the quantity of separated solid reaches a maximum. A comparison of the deposition of bitumen in the field with the separation of asphalts from lubrication oil has been made' and apparently the phenomena are similar. The phase behavior of bitumen also appears to be comparable to that of coal tar."' The chemical and physical characteristics of asphalts and bitumen have been the subject of extended investigations which have been reviewed in some detail by Katz.¹º The conclusion was reached that the dispersion of bitumen in a number of organic liquids was not entirely colloidal since it was impossible to isolate individual dispersed particles even with the electron microscope. However, the evidence appeared to indicate that at states close to phase boundaries the extent of the dispersion of the phases influenced the equilibrium to a greater extent than is encountered in many simpler systems. From earlier study of field samples it became apparent that the phase behavior of bitumen-hydrocarbon systems was unusually complex. It was difficult to characterize in detail the phase behavior involved in naturally occurring hydrocarbon systems, even after a relatively extended investigation. For this reason, the study of a somewhat simpler system which still behaved in a similar manner became desirable. Three major constituents were necessary as-follows: a bituminous solid, a liquid constituent which was a reasonably good solvent, and a constituent in which bitumen was largely insoluble. A sam-

Jan 1, 1949

By F. F. Poland

The purpose of this paper is to describe a new process for the refining of secondary copper-base metals and a specially designed high-temperature electric-resistor furnace used in the process for the distillation of zinc from these metals. The process was used for the conversion of nickel silver to cupronickel and to recover the zinc content in metallic form. It also proved applicable and economical for the treatment of scrap brass for separating and reclaiming the copper and zinc. The relatively large furnace developed for the distillation of zinc is described in detail, for it made economically possiblc the direct recovery of metallic zinc from scrap brass, which is a new step in the processing of such material. Considerable interest has been shown in the utilization of the distillation furnace for other metallurgical processes, where it is of advantage to operate in a controlled neutral or reducing atmosphere, or to avoid having the processed metal in contact with refractories other than carbon, or to operate at temperatures between 3000 and 4000°F. Purpose of Development It was recognized early in the war effort that nickel would become a critical metal. therefore all nickel stock and alloys containing relatively high percentages of nickel were frozen immediately. Among these alloys were considerable quantities of various grades of nickel silver, an alloy containing copper, nickel, zinc, and in some grades lead, also minor amounts of iron, manganese and other constituents. At the time there was no existing plant or process to eliminate the zinc, lead, and minor constituents so as to convert this metal to cupronickel, one of the important alloys needed by the U. S. Navy for condenser parts. Therefore the Bureau of Industrial Conservation of the War Production Board requested the executives of the leading nonferrous metal companies to have their metallurgical staffs study the problem of converting this metal to cupronickel conforming to U. S. Navy Specification 44T40. The composition specified therein is as follows: nickel, 29 to 32 per cent; zinc, 1.00; iron, 0.00 to 0.60; lead, 0.05; tin, 1.20; manganese, 0.00 to 1.00; total of other elemcnts (maximum). 0.50; copper, remainder. The problem in converting these alloys to cupronickel was the elimination of zinc, lead, iron, manganese, and other elements without appreciable loss of nickel to slags or other by-products. Revere Copper and Brass Incorporated, through its Research and Development Department, undertook to solve this problem. A Government-owned plant was built at Rome, N. Y., and there the conversion was made successfully.

Jan 1, 1949

By R. S. Sanford

The Claim Point chromite deposits are at tidewater near the southern tip of the Kenai Peninsula in southwestern Alaska, The United States Geological Survey had a field party in the region from July until September 1940 under P. W. Guild, assistant geologist; maps and geological data were assembled and made available to the Bureau of Mines. A preliminary investigation of the deposits at Claim Point by the senior author during July 1941 was followed by surface sampling and core drilling to determine the quantity and grade of the ere, The Geological Survey was represented at the project by George O. Gates, geologist. Cores were checked and the structural data revealed by drill cores were interpreted. The principal chromite deposits have been sampled and delimitated by trenching and core drilling. Other deposits were trenched and sampled but were too small or too low-grade to warrant core drilling.

Jan 1, 1949

By S. Benedict Levin

In the spring of 1944, during the emergency In the supply of strategic mica, the Bureau core-drilled six aggregating 913 feet, at the Blister mica Trim. Cheshire County, N.H. These holes indicated a downward extension or the mica shoot which was being mined at that time and developed information essential for economic mining of the deposit.

Jan 1, 1949

By Michael Tenenbaum

The importance of semikilled steel as a high tonnage grade has long been recognized. The increasing severity of the applications for which semikilled steel is used makes it desirable to obtain further information regarding the features of open hearth practice and ingot structure that can affect steel performance in subsequent rolling and fabricating operations. Accordingly, an investigation is being carried out studying the structure of various types of semikilled steel ingots. This paper reviews some of the observations made and information gathered in this investigation. By definition, semikilled steel may be considered to include all nonrimming steels in which the natural shrinkage occurring during ingot solidification is offset to an appreciable degree by gas formation. Accordingly, this type of steel includes the entire range intermediate between rimmed and fully killed steel. The resultant ingot structures range from those of steels that have been capped to suppress a weak rimming action to those steels that have been killed in the furnace or ladle to the extent that no mold deoxidizer is required. A survey reported to the 1946 -AIME Open Hearth Conference' reviewed the practices being used at 28 major plants for the deoxidation of semikilled steel. It was found that most plants divide the deoxidizing additions between the ladle and the mold—many of the plants adding only minor amounts of deoxidizer to the bath or none at all. Silicon, aluminum and titanium were the only elements used for ladle and mold deoxidation. Mold deoxidizers were added as capping additions or as uniformly fed additions. Several practices were reported in which the steel was deoxidized in the ladle to the extent that little or no mold deoxidation was needed. No reference was made to grades capped by using special mold designs or special closures over the top of molds. .Accordingly, specific examples of this type of practice will not be considered in this paper. It appeared from this survey of deoxidation practice that semikilled steel can be divided into three types, namely, capped semikilled, in which aluminum is added near the end of pour or after shut-off, intermediate semikilled steels, in which aluminum is fed uniformly throughout the pour, and semikilled steels requiring no mold deoxidation. In an attempt to cover the ingot structures obtained by the range of practices reported in the preceding survey, three series of experimental heats were made using increasing amounts of aluminum, silicon and titanium for ladle deoxidizers. The ladle deoxidizers were added as stick aluminum, 50 pct ferrosilicon and 20 pct ferrotitanium (4 pct carbon), respectively. Two methods of studying ingot structures were used. Ingots were removed from production, burned longitudinally and machined to allow observation of the central pipe and coarse blowholes. During the machining operation much of the finely porous subsurface structure was obliterated. Accordingly, observations were also made

Jan 1, 1949

By Nelson B. Russell, Donald C. Bond

The effects of various antifreeze agents on the formation of hydrogen sulphide hydrate have been studied. On a molar basis the relative lowering of Tm (the maximum temperature at which solid hydrogen sulphide hydrate can exist in equilibrium with the given solution) for the various agents is: sodium chloride 1.00, calcium chloride 1.71, methyl alcohol 0.57, ethyl alcohol 0.68, ethylene glycol 0.73, diethylene glycol 0.73, sucrose 0.87, dextrose 0.71. On a weight basis the relative lowering of TM is: sodium chloride 1.00, calcium chloride 0.91, methyl alcohol 1.08, ethyl alcohol 0.89, ethylene glycol 0.69, diethylene glycol 0.41, dextrose 0.23, and sucrose 0.15. Introduction The solid hydrate of hydrogen sulphide, H2S.6H20,1 is in equilibrium with water and liquid hydrogen sulphide at 85°F at a partial pressure of hydrogen sulphide approximately equal to the vapor pressure Of hydrogen sulphide at that temperature. At temperatures below 85°F, in the presence Of excess hydrogen sulphide (greater than the amount required to react with the water present) the hydrate is in equilibrium with liquid hydrogen sulphide at approximately the vapor pressure Of hydrogen sulphide. In the presence of excess water, the solid hydrate is in equilibrium with liquid water, containing dissolved hydrogen sulphide, at a pressure lower than the vapor pressure of liquid hydrogen sulphide at the same temperat~re.2 The lower the temperature, the greater the difference between the decomposition pressure of the hydrate and the vapor pressure of liquid hydrogen sulphide at that temperature. Conditions conducive to the formation of solid hydrogen sulphide hydrate may exist in wells producing a gas containing a high percentage of hydrogen sulphide under high pressure, or in the lead lines from such wells. This paper gives the results of tests made with various antifreeze agents which might be useful in decomposing the hydrate or in preventing the formation of the hydrate of hydrogen sulphide Apparatus Fig , shows a diagram of the apparatus used. The sample under observation was contained in a glass tube 34 cm long, having a 6 mm id and a wall thickness of 2.5 mm. The lower end of this tube was closed- with a plug of butyl rubber. The upper end of the tube was connected to a diaphragm gauge, with a stainless steel diaphragm, a manometer, a vacuum pump, and a cylinder of hydrogen sulphide, The tube was held nearly horizontal, with the liquid resting along the lower side of the tube. It was found that when the tube was held in a vertical position, it broke with ex. plosive violence as soon as it became filled with solid hydrate. Presumably this was caused by the expansion which occurred on solidification of the hydrate. The difficulty disappeared when the tube was held in an inclined position during the tests.

Jan 1, 1949

By Walter Rose, W. A. Bruce

Improved apparatus, methods, and experimental techniques for determining the capillary pressure-saturation relation are described in detail. In this connection a new multi-core procedure has been developed which simplifies the experimental work in the study of relatively homogeneous reservoirs. The basic theory concerning the Leverett capillary pressure function has been extended and has been given some practical application. Some discussion is presented to indicate the relationship of relative permeability to capillary pressure, and to provide a new description of capillary pressure phenomena by introducing the concept of the psi function. INTRODUCTION For the purposes of this paper the capillary character of a porous medium will be defined to express the basic properties of the system, which produce observed results of fluid behavior. These basic properties may be classified in the following manner, according to their relationship to: (a) The geometrical configuration of the interstitial spaces. This involves consideration of the packing of the particles, producing points of grain contact, and variations in pore size distribution. The packing itself is often modified by the secondary processes of mineralization which introduces factors of cementation, and of solution action which causes alteration of pore structure. (b) The physical and chemical nature of the interstitial surfaces. This involves consideration of the presence of interstitial clay coatings, the existence of non-uniform wetting surfaces; or, more generally, a consideration of the tendency towards variable interaction between the interstitial surfaces and the fluid phases saturating the interstitial spaces. (c) The physical and chemical properties of the fluid phases in contact with the interstitial surfaces. This involves consideration of the factors of surface, interfacial and adhesion tensions; contact angles; viscosity; density difference between immiscible fluid phases; and other fluid properties. Fine grained, granular, porous materials such as found in petroleum reser~oir rock possess characteristics which are expressible by (1) permeability, (2) porosity, and (3) the capillary pressure-saturation behavior of immiscible fluids in this medium. These three measurable macroscopic properties depend upon the microscopic properties enumerated above in a manner which defines the capillary character. Systems of capillary tubes or regularly packed spheres may be thought of as ideal and numerous references can be cited in which exact mathematical formulations are developed to show the relationships governing the static distribution and dynamic motion of fluids in their interstitial spaces. The capillary character of non-ideal porous systems such as reservoir rock also is basic in determining the behavior of fluids contained therein; although, in general, the connection is not mathematically derivable but must be approached through indirect experimental measurement. This paper gives consideration to the evaluation of petroleum reservoir rock capillary character. The methods employed may be applied to the solution of problems in other fields, and the conclusions reached should contribute to the basic capillary theory of any porous system containing fluid phases. In this paper, a modification of the core analysis method of capillary pressure is employed and it is intended to show that the capillary character of reservoir rock can be expressed in terms of experimental quantities. A very general method of interpretation correlating the capillary pressure tests with fundamental characteristics such as rock texture, surface areas, permeability, occasionally clay content and cementation is introduced. Eventually an attempt is made for establishing a method of deriving relative permeability to the wetting phase from capillary pressure data. The experimental evaluation of capillary character must be approached in a statistical manner if reservoir properties are to be inferred from data on small cores. This is implied by the heterogeneous character of most petroleum reservoirs, and suggests that considerable intelligence should be applied in core sampling. Finally, this paper supports the view that once the capillary character of a given type of reservoir rock has been established by core analysis, fluid behavior can then be inferred in other similar rock. Although no great progress has been made in establishing what variation can be tolerated without altering the basic fluid behavior properties, evidence will be presented to indicate that certain reservoir formations are sufficiently homogenous with respect to capillary character that the data obtained on one core will be useful in predicting the properties of other cores of similar origin. Tests have shown that cores under consideration can vary widely with respect to porosity and permeability and still be considered similar in capillary character. EXPERIMENTAL METHODS AND TECHNIQUES Various types of displacement cell apparatus for capillary pressure experiments have been described in the literature. Bruce and Welge; Thornton and Marshall; McCullough, Albaugh and Jones3; Hassler and Brunner; Lever-

Jan 1, 1949

By William F. Jahn

Because of the' situation in Europe during the summer of 1939, with the possibility of war and consequent curtailment or loss of supplies of tin to the United States, the Bureau of Mines undertook an investigation of domestic tin resources. This was permitted by the Strategic Minerals Act of 1939, which authorized investigation of possible domestic resources of strategic minerals necessary in a national emergency. The minerals selected were in short supply, and the United States depended almost entirely on imports to meet normal requirements. The Black Hills of South Dakota were selected for investigation as one possible source of tin because of the occurrence of the mineral there has been known since 1876, although production had never been important. The Tinton area, in the northern part of the Hills, had received the most attention and contained some minor indicated and inferred tin deposits.

Jan 1, 1949

By William C. Martin

"Consolidated Sudbury Basin Mines Limited owns two mines, 4 miles apart, near the southwest end of Sudbury Basin. The Errington mine lies close to the north boundary of Creighton Township and about 18 miles by car from Sudbury. The Vermilion Lake mine is in Fairbank Township, on the south side of Vermilion Lake.The first discovery of base-metal mineralization within Sudbury basin was made by James Stobie in 1897 at Stobie Falls on the Vermilion River, half a mile west of the Errington mine. A few years later Alphonse Oilier made a discovery of massive pyrite with base-metal sulphides near the west end of the present Errington workings.No work of consequence was done on these discoveries until 1924, when Joseph Errington acquired options on a large acreage of ground which was later taken over by the Treadwell Yukon Company Limited. After considerable diamond drilling this company sank No. 1 shaft in 1926. In the next three years, a large amount of underground development was done, a pilot mill was constructed and operated for two years. All operations ceased in 1931 with the fall in metal prices. While in operation the pilot mill treated 186,172 tons of ore the average grade of which was 1·07 per cent copper; 1 10 per cent lead; 4·60 per cent zinc; 0·03 ounces gold; and 1 70 ounces silver.Up to the time of closing in 193 l there had been completed at the mine 26, 790 feet of lateral work and 75,500 feet of surface and underground diamond drilling. The company records, however, showed no figures on ore reserves, except broken ore in stopes amounting to about 60,000 tons. A study of the plans, prior to reopening the mine in 1952, showed 1,450 lineal feet of ore (at 1952 prices) opened up by drifting on the 300-foot and 500- foot levels. It is clear that no comprehensive picture of the structure was had at this time. The orebodies were considered to be very irregular pods scattered through masses of quartzite-carbonate in a sheared zone about 800 feet wide. In some way the ore was believed to be related to the tuff-slate contact zone. With this picture it was impossible to make a reasonable ore estimate or even gauge the tonnage potentialities with any feeling of reliability."

Jan 1, 1949

By O. S. Perry, D. F. Kidd

"BEAVERDELL IS IN the Interior Plateau of British Columbia, 25 miles east of Penticton, B.C. In 1897, small but rich silver-bearing veins were found on Wallace Mountain, 2 miles east of Beaverdell. Production from the camp, at first of a modest character, started in 1901 and has never ceased. Over 90 per cent of the values in the ores have been in silver. Remaining values present are in lead, gold, zinc, and cadmium.There have been four principal mines in the camp. A fifth is approaching production. The four mines lie within a northeasterly trending rectangle about 5,000 feet long and 2,000 feet wide, the fifth mine being at the northeast end. From southwest to northeast the mines, with their silver production to Sept. 30, l 955, are: -Wellington Mine - 1,463,948 oz.Sally Mine (includes Rob Roy claim) - 1,930,124 oz.Bell Mine - 3,460,815 oz.Lass Mine - 12,557,956 oz.Other production - 331,252 oz.Total, Beaverdell Camp - 19,744,095 oz.The camp is near the centre of an area geologically mapped in 19 l l by L. Reinecke for the Geological Survey of Canada (1). The rocks of the camp comprise:1. Beaverdell stock of porphyritic quartz monzonite;2. Westkettle batholith of quartz diorite;3. Wallace formation of tuffs and lavas.The Wallace formation borders the east edge of the camp, and has been intruded by the Westkettle batholith. The batholith is the host rock for the orebodies. The Wallace-batholith contact dips gently east. Some of the Beaverdell ores at depth, while in the batholith, are under Wallace formation mapped on the surface above.West of the camp, Reinecke mapped a stock one by one and one-half miles in size, of porphyritic quartz monzonite, which he considered much younger than the Westkettle quartz diorite (I). Recent petrographic work by White and Dolar-Mantuani (3) suggests that in the vicinity of the camp the Westkettle batholith is more quartz monzonite than quartz diorite, and little different in composition from the Beaverdell quartz monzonite. They suggest a consanguinity with the Westkettle batholith."

Jan 1, 1949