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By J. E. Gosline

IN any theory of a hydrodynamic nature dealing with the vertical flow of gas-liquid mixtures in pipes, the two factors that present the greatest difficulty are the relative motion between the phases and the energy loss resulting from turbulence work. The former has generally been referred to in the literature as "slippage" and the latter as "fric-tion." A third factor of importance is the nature of admixture between liquid and gas for both the relative motion between the phases as well as the turbulence work are functions of the type of mixture. Although much work of a general nature has been performed on the vertical flow problem, there have been very few attempts made to study experimentally the factors involved in the phenomenon individually. Of these, perhaps the most notable is the work of Moore and Wilde1 on slippage. Some writers on the subject have assumed that over a wide range of operating conditions the controlling type of mixture, is one in which gas bubbles of uniform size are distributed throughout the liquid, and that the data obtained from experiments on the motion of single bubbles through various liquids may be used in evaluating the slippage. Ver-sluys2 has further assumed another controlling type of mixture in which the liquid occurs as a dispersed phase within the gas and applies data on the fall of drops of water in air to calculating the relative velocity. It was for the purpose of studying the applicability of data on single bubble motion to the slippage factor and to further observe the nature of mixtures that a research program was conducted at the University of California during 1932 and 1933. These experiments formed a basis for

Jan 1, 1935

By Sylvain J. Pirson

The number of seismograph field crews employed in the active survey of potential oil territories is still on the increase, owing to the ever pending threat of a shortage in the supply of crude oil. It is to be expected that for years to come the seismograph will be responsible for discovering many new oil fields, both in wildcat territories and in deeper formations, and that the seismographic campaign will go on unabated. Yet improvements in instrumental design, in the field and interpretative techniques, are brought about year after year, and lead to the reshooting of areas many times surveyed previously. Notwithstanding the experience gained by the past eight years of active work in reflection seismographic surveys, the results given by this method of mapping deep formations have in many instances been at variance with the information subsequently obtained by the drill. To overcome this shortcoming, geophysicists have used closer spacing of the shot points and closer control of the depth points. The method discussed here is being used actively in the Mid-Continent region and endeavors to reduce the interpretation work to a mere mechanical technique, leaving as little as possible to the opinion of the interpreter. The New Method Field Technique.—In sectionized territory where country roads are available every mile, shot points are preferably located every 1/4 mile when six detectors are available or every % mile when eight detectors are at hand. The disposition of individual spreads is represented on Fig. I; in each case a shot point is located at the section corners. Fig. 2a represents the layout of a spread between shot points, the vibration detectors being preferably equidistantly located. Normally in the 1/4-mile control, the distance between shot points is 1320 ft. and the distance between detectors 220 ft. When shooting from shot point S.P. I, detectors 1 to 6 are connected to the recording galvanometers and detector 0 (which indicates the vertical travel time of the wave corre-

Jan 1, 1940

By C. D. Rubert, W. J. Parton

LARGE quantities of fine anthracite with associated impurities are discharged with the waste water from the coal-cleaning plants in the Pennsylvania anthracite region. Furthermore, for many years this fine material has accumulated and formed silt banks. The difficulty of removing the impurities from the fine material and the lack of adequate markets are responsible for the waste of this material. In view of a larger demand for fine coal, mainly for pulverized fuel, the Lehigh Navigation Coal Co. Inc. decided to investigate the froth flotation process for recovery of fine coal from these waste solids. A test plant was constructed and operated for six months during 1942 in order to determine the practicability of recovering coal from the waste water of a cleaning plant (breaker) by froth flotation, and to obtain operating data for designing a commercial plant if the results were favorable. PRELIMINARY INVESTIGATION Before the pilot plant was constructed information was obtained by field and small-scale laboratory tests to serve as a guide in the design and operation of the pilot plant. Size and ash analyses of a representative sample of the material discharged in the wash water from a cleaning plant are given in Table I. [ ] The refuse content increases progressively as the size of the particles decreases. The larger particles (+35 m.) are low in ash content and could be marketed without cleaning. Since these solids are discharged from the breakers with 90 to 95 per cent water by weight, the first step in the recovery of the coal was that of reducing the quantity of water so that water in excess will not have to be handled. Furthermore, it was found that the removal of most of the minus 200 mesh high-ash material was desirable to permit the most efficient flotation of the coal. Classification tests were run and showed that a hydroseparator overflow rate of 12 ft. per hour was sufficient to eliminate much of the minus 200-mesh material while allowing the coarser material to settle and be thickened.

Jan 1, 1944

By Gerald Sherman

Mine fires are always dangerous and are frequently accompanied by loss of life during the period of confusion which is apt to follow their discovery. In metal mines, fires may result from the accidental ignition of combustible material, or they may be of spontaneous origin resulting from the rapid decomposition of sulphide. They occur frequently enough to demonstrate the need of some special equipment and a general plan for controlling them, in addition to measures for their prevention. Nearly all the large copper mines have had fires, and the methods of fighting them have been well described in recent papers, notably by C. L. Berrien,1 R. E. Tally,2 and others in discussion. The Copper Queen mine has many shafts, which are connected by underground workings. The deeper parts are ventilated by fans, but in the shallower portions natural ventilation through numerous connecting raises or shafts is sufficient. There have been several fires in the past few years, of which all are extinguished but one, which is under control. These notes cover particularly the preparations that are being made to check a new fire, partially or temporarily, and to facilitate the escape of workmen in the interval before a definite plan of fighting it can be established. A fire may occur in a shaft or station, or in some working farther away. In case of fire in an upcast shaft, the gas would escape to the surface and the immediate result would probably not be dangerous to workmen, as they could escape by other shafts. In a downcast shaft, however, the gas would be distributed very rapidly throughout a large portion of the mine, and men might easily be trapped and asphyxiated. A fire in mine workings, drift, raise, or stope, would be dangerous in a degree, but the draft there is likely to be less strong than in a shaft and probably a smaller area would be invaded by the fire gases. At the Copper Queen mine, in all drifts connecting with individual

Jan 1, 1918

By W. R. Ingalls

THE bases of the work by the committee whereof I am chairman were (1) the abolition of extra-lateral rights and (2) the preservation of the maximum of the existing laws. The matter of extra-lateral rights had been under prolonged discussion among mining men and up to the time when our com-mittee began its work (in 1917) the expression of opinion in every way whereby it could be made known -and those ways were extensive-was only a little short of being unanimous that extralateral rights ought to be abolished. I have not observed important evidence indicating a change of opinion on the subject since 1917. ABOLITION OF DISCOVERY LOGICAL Now, when it be decided that extralateral rights ought to be abolished, there can not be merely a simple change to that effect, but it is found that consequential changes are necessary all the way through the existing laws. Abolition of extralateral rights implies abolition of discovery as a prerequisite to location, for otherwise there would be no legal means for locating claims on the dip of a vein. Quite apart from this consideration, abolition of discovery as a prerequisite to location is supported by other good reasons. Among these are the occurrence of orebodies with no exposure on the surface and which often are hidden at great depth. A prospector who has reason to suspect the occurrence of such an orebody must have legal means for the location of a claim within which to explore, and obviously he may. not be able to make any discovery on the surface sufficient to locate and hold legally such a claim under the terms of the law as it stands at present. As a matter of fact, discovery as a prerequisite to location was abolished by common consent many years ago, not only for the reasons that I have given here-inbefore but also for others. It is highly desirable to revise the mining law in this respect, so that it will conform to the conditions of practice and not require people to perjure themselves in making locations, even if it be for praiseworthy purposes.

Jan 6, 1922

By James Norman

DIATOMACEOUS earth occurs in deposits widely distributed throughout the nation. The chief producing areas are in the Western States, where many high-grade deposits are known. Eastern deposits of diatomite are unsatisfactory for many purposes either because of impurity or because of the extremely fine particle size. Eastern users of diatomite, on the whole, must pay for transportation of the material from the west coast. The freight rate is necessarily high because of the great bulk of the diatomite. A satisfactory process of purifying the diatomaceous earths of Maryland and Virginia, which are unsuited for wide use only because of impurities, should be of value to eastern users. In the past, benefication of diatomite by wet processes has been limited to classification or sedimentation for the removal of sand from diatoms. Calcination with salt is used to produce a white diatomite when iron is present in the impurities, and small amounts of clay are rendered inactive in the process. No treatment has been developed whereby a large proportion of clay can be removed from a low-grade diatomaceous earth to give a diatomite of very high purity. In August 1937 the Federal Bureau of Mines, in cooperation with Dr. R. C. Williams, of Baltimore, undertook the problem of purifying low-grade Maryland diatomite by froth flotation. Work was done at the Eastern Experiment Station, College Park. Unless otherwise stated, the crude diatomite used was from the Patuxent River deposits near Dunkirk. This material, consisting of roughly one-third each of clay, quartz sand and diatoms, was representative of the usual low-grade marine diatomite found in the Coastal Plain Miocene beds of Maryland and Virginia and sporadically in other Atlantic coast states. As received, it contained 50 to 60 per cent moisture and probably had been wet since its formation.

Jan 1, 1940

Discussion of the paper of PHILIP W. HENRY, presented at the New York meeting, February, 1915, and printed in Bulletin No. 97, January, 1915, pp. 23 to 30. C. ,E. GRUNSKY, JR., San Francisco, Cal. (communication to the Secret ary*).-The difference of opinion of engineers on the subject of depreciation is justified, to some, extent, by the many viewpoints from which such a subject can be considered when applied to properties of widely differing physical characteristics. Mr. Henry takes up the subject of depreciation as applied alone to oil properties, and in doing so makes a clear distinction between amortization and the repair or renewal requirement. After carefully reading the paper the purpose of its author in suggesting a "depreciation" reserve or fund to keep the property at a constant value does not seem clear. As shown by Mr. Henry, the depreciation element as compared with the operating expense per gallon of oil is very large because of the comparatively short life of the oil properties, and it is also evident that such a "depreciation" fund would in a short time contain a very large amount of money. It seems desirable and permissible in income-tax matters to take into account the depreciation of property and to separate from the income such money as is necessary to amortize the invested capital to an extent warranted by the depreciation. However, it does not seem either necessary or desirable to create a large fund which will in time approximate the entire invested capital and which may he invested by the directors, as Mr. Henry suggests, "in the property itself or in outside securities." This method seems cumberome and liable to offer in the reinvestment of such a fund temptations to a directorate that might show more devotion to its own interests than that of the stockholders. A reserve fund is very frequently desirable in mining and oil operations, but to keep up a fund of this magnitude or to reinvest it in outside securities does not seem desirable from a stockholders' standpoint. The. money withdrawn from the receipts to be placed in the depreciation fund (not including replacements and the drilling of new wells necessary to keep up the productiveness) should he returned to the stockholders of the company, not as dividends, but as an amortization of the invested capital.

Jan 5, 1915

By W. L. Maxson

GRINDING is one of the major problems in present-day milling practice, and in many cases, it represents one of the main items of expense. It becomes necessary from time to time, to compare grinding practice in one plant with that in another plant, and in making such comparisons, it would be very desirable were there available accepted standards of grinding resistance for the materials involved. Such a set of grinding constants would also be of considerable value in planning new grind-ing installations. There have been some tests published, notably those of Lennox,1 which have been generally cited as a basis for such comparisons. Most of the tests made have been based upon open-circuit grinding, in which a weighed sample of the ore was crushed to pass a certain mesh, and was .then ground under certain conditions, either wet or dry. Grinding was continued until a certain desired fineness was attained, and the compari-sons based on the grinding time, or the samples were all ground for a certain specified length of time and comparison based upon the screen analysis of the products. Such methods have been acceptable where the ore was to be ground in open circuit. However, in modern milling practice, many grinding problems involve closed circuits wherein the oversize returns to the mill and a large circulating, load builds up. A method of testing that does not take the circulating load into consideration might yield results quite different from those to he expected in practice, because the minerals in the ore that offer maximum resistance to grinding will accumulate in the circulating load up to an equilibrium value. Thus the nature of the ore charge in the mill at any instant may differ greatly from that of the new feed, with a consequent error in the rate of grinding determined by such a method.

Jan 1, 1933

By John B. Pearse

IN order to get an idea as to the strength of steel rails, it will be well to review the tests to which iron rails have been subjected. In England, Mr. Ashcroft found that the best 80 pound rails broke under a 300 pound weight, falling 15 feet. In Germany the Society of Railway tyfanage1-s determined 011 and have long applied a test of 1000 pounds falling 101/2 feet, as the standard which all first-class iron rails must reach. In this country no inspection nor test is applied, but tests made show that iron rails fro; our most reliable makers, break under a G foot fall of a 1500 pound drop as an extreme test, most of those tested breaking under a far less test; some breaking with less than a 3 foot fall of the same weight. Everywhere where steel has been used, engineers have come to the conclusion that some test is required to show the regularity and strength of the product. As compared with iron, the tests which steel will stand are wonderful. After numerous experiments partially based on the experience of the rail-mill at Graz, belonging to the Southern Railway of Austria, the Society of German Railway Managers fixed upon a test of 2000 pounds falling 138 feet. They found that this test represented the steel which suited their necessities, and also found that with steel of otherwise average purity, this test represented about one-half per cent. of carbon, and made it a rule to take no steel containing under three-tenths of a per cent. of carbon, because it was too soft. They expressed a hope that a harder steel could soon be made tough enough to stand the same test. I n England, a test was adopted of 2240 pounds, falling 15 to 17 feet on the rail on heavy bearings. This test has been found satisfactory under heavy traffic on average road-beds, and has been invariably

By John Birkinbine

A retrospect of the growth of the production of pig-iron for the past half century would be the history of the invention and introduction of heated blast as applied to the smelting of iron ores. As the apparatus employed was improved in conception and construction, the economical operation of the furnaces to which it was attached was the more marked, and the production correspondingly increased. To compare the original iron box placed over a coal fire with the modern hot-blast stove, with its combustion-chamber, gas-burners, and air-regulators, would be as unfavorable to the former as to contrast the product of the little Blauöfen with the yield of the improved furnaces of to-day. But, as these little Blauöfen were the germs from which the larger plants have grown, so from the crude apparatus invented and applied by Neilson has grown, in the face of great opposition, the more economical hot-blast stoves now in use. It is not surprising that an innovation like heated blast should have received a large amount of attention from metallurgists, nor that men of recognized ability should formerly have been found both among its champions and opponents, but it is remarkable that, at the present day, with the results of careful research and thorough experiment compiled in convenient shape for perusal, there are ironmasters who still consider it economy to allow the products of combustion to escape into the atmosphere, rather than utilize them in heating the blast, because of a supposed injury to the quality of the product. In the present state of knowledge and practice, it is proper to express as an axiom, that a well-constructed hot-blast apparatus is essential to the economic operation of an iron-producing plant. Of the interpretation of proper construction there is of necessity a variety of opinions, and, with the view of solving the problem, the apparatus for heating blast has from time to time assumed various forms. Boxes, cylinders, and pipes, placed horizontally, vertically, inclined, or in circles and spirals, have been tried; there have been pistol-shaped pipes, double pipes, divided or diaphragm pipes, siphon pipes, and as much variety in the mains, connections, flues, and setting. It is probable that, to the introduction of the bell and hopper in

By H. Evans, L. A. Hunt

The raw materials used in the blast furnaces at the Geneva Works of U.S. Steel Corp. have a high degree of variability in size-consist and chemical content. To overcome the problems caused by the use of highly variable raw materials in the blast-furnace operation, large blending piles are used. An investigation of the blending system showed that variability was significantly reduced by the use of these blending piles. This paper describes the blending system, the method used to evaluate the effect of the blending system, and the results of the investigation. The remarkable improvement in blast-furnace performance since World War II has been in large measure due to the use of beneficiated burdens to reduce the variation of both chemical analysis and size consist. This practice allows the operator better control of his blast furnace, enabling him to operate more economically and to produce chemically uniform hot metal. Planning for uniformity usually begins during mining by extracting ore from several locations within a pit to produce a final product with a specified analysis. Another approach is to stockpile ores having widely varying analyses in individual piles and then drawing the required amounts from each stockpile to provide a blend with a predetermined analysis. A further improvement in blending procedures is to take ores from several sources, bedding them horizontally in layers and reclaiming by vertical slicing from the blended pile. The last procedure, when properly executed, is one of the best methods for achieving maximum uniformity with highly variable ores. U.S. Steel Corp.'s Geneva Works initially obtained iron ore for their blast furnaces from the Cedar City area of southern Utah. These ores were formed primarily by the replacement of limestone and siltstone formations with solutions containing iron and several other elements. The original iron content of the ores in the ground varied from a high of 70% to practically zero with a minimum acceptable iron content for shipping of 37%. Substantial amounts of silica, calcium, magnesium and alumina were found in the ores along with minor amounts of copper, lead, zinc, nickel, titanium, manganese, phosphorus and sulfur which were sometimes present in detrimental amounts. Iron-to-silica ratios varied considerably throughout

Jan 1, 1968

By William E. Newman

Lead mining has been carried on in several localities of the Province of Ontario in a desultory fashion for the past 60 years, but up to 1916 the results have not been of much commercial importance. The most ambitious attempt was made by an English company which built a lead smelter at Kingston, Ont., in 1880 to treat the concentrates from the Frontenac mines. After 2 years' operation, the mines and smelter were abandoned. Up to the present there has not been a sufficient tonnage of concentrates to support an efficient blast-furnace plant and as most of the small properties could not stand the heavy freight and duty charges into the United States, development work has not been carried on in a systematic manner. As a result the industry has languished. At Galetta, in southeastern Ontario, considerable prospecting and development work has been carried on in the last few years and very promising deposits of galena have been found in the Chats Island group by the James Robertson Co., Ltd., of Montreal. The chief deposit is that of the Galetta or Kingdon lead mine, located on Chats Island in the Ottawa River about 5 miles east of the town of Arnprior. The rocks1 in the vicinity of the mines consist of an interbedded series of crystalline limestone and biotite gneisses of pre-Cambrian age. This part of the Ottawa River basin has been severely faulted and the overlying Paleozoic limestones may be seen in normal fault cantact with the pre-Cambrian. The vein filling is of a very well-marked fault fissure type and although the amount of displacement is not determined at this point, similar faults to the east show a displacement of from 1,500 to 1,800 ft. which would indicate mineralized fault fissures of considerable depth. The ore occurs in a highly crystalline calcite with some barite and fluorite, and the galena occurs more or less richly disseminated in clusters and crystal aggregates. In some cases these masses weigh several hundred pounds. Small amounts of sphalerite are occasionally encountered.

Jan 1, 1918

By D. V. Carter, Dan C. Williams, Franklin M. Hackbusch

During 1939 little of consequence happened in East and East Central Texas in the way of oil discoveries. At the end of the year, there were 47 oil and gas fields in the district. Twelve other fields, 11 oil and one gas, have been abandoned. The ranking fields in order of the number of completions for the year were East Texas, Talco, and Rodessa (Texas portion). There were 511 oil wells (distillate wells included), 32 gas wells, and 257 dry holes completed in the district. Exploration, Discoveries and Extensions During the year, 113 exploratory wells were drilled, the same number as in 1938; four oil fields and one gas-distillate field were discovered. Perhaps the most important discovery, which has been named Barron field, was that of M. Samuel et al., No. 1 Barron in Limestone County. The wells in this field are of the gas-distillate type. Other than the Talco and Sulphur Bluff fields, which produce oil from the Paluxy sand (Upper Trinity), this is the first field on the Corsicana-Mexia fault zone to obtain commercial production from deeper Trinity strata. This "pay" is the Petit lime of the Lower Glen Rose of the Trinity group. The four oil discoveries were: Redland, Angelina County; Bazette, Henderson County; Rowe and Baker, Henderson County; and Marion County Shallow in Marion County. It is believed that the Bazette field, Navarro County, represents an extension of the Flag Lake field. For details concerning discoveries, extensions and important wildcat wells drilled during 1939 see Table 2. Production and Proration The district produced 175,053,729 bbl. of oil (distillate production included) which is a decrease of 4.0 per cent from the 182,369,484 bbl. (distillate production included) produced during 1938. The district's production for the year 1937 was 208,594,453 bbl. The East Texas

Jan 1, 1940

By Earl R. McMillan

Though much has been written during the past several years about the Russian success in using hydraulic jets for coal mining, little or none of the published information, in so far as this writer has observed, has been of any use or practical application in this country. It is true, according to their published reports, that the Russians were pioneers in the use of high-pressure water jets in the mining of coal. They report the use of water jets for this purpose as early as 1936. However, according to a survey of foreign literature on the subject made by the U.S. Bureau of Mines1 a few years ago, water jets in the USSR, as well as in other nations including New Zealand, Poland and West Germany, were used principally to sluice the loosened coal after it had been previously drilled and blasted, rather than to cut or break it from the solid face. The interest of the Northern Pacific in the potential application of a high-pressure water jet to the actual extraction of coal, particularly in steeply dipping beds, originated in a visit by this author to the operations of the American Gilsonite Co. at Bonanza, Utah, in March 1958. After seeing the extraction, on a commercial basis, of gilsonite from a 22-ft wide vertical vein of this solid material with a 3/8-in. diam stream of water under approximately 2200 psi, it was felt that, with some modifications, water jets were the solution to the problem of economically mining the steeply dipping (i.e., steeper than 20º) coal beds in the State of Washington.

Jan 6, 1962

By C. Erb Wuensch

The Eagle mine is situated in the Kerber Creek mining district, Bonanza, Saguache County, Colo. The climate and topography of this district arc similar to those of mining camps of the Rocky Mountain region that lie 9000 to 12,000 ft. above sea level. The district is at the northeasterly edge of the San Juan volcanic region, in which successive Tertiary lavas have built up a high plateau resting upon earlier sedimentary formations, or the underlying pre-Cambrian complex. The latter was exposed in places by erosion previous to the eruptions. In the Bonanza district, proper, only volcanic formations, andesites and latites, are found. Dr. H. B. Patton,1 in his survey of the district, discriminates between several varieties of lavas and maps these as distinct flows. They are local variations within the same lava and it is impossible to determine any distinct line of demarkation between them. Structurally they are members of the same flow. There are three general types of vein occurrences: 1. Lead-zinc-copper-silver-gold veins in well-defined fissures with a quartz gangue; ill these, the various sulfides show a zonal arrangement. 2. Massive gray copper ores high in silver, in irregular fractures in the form of small lenses and pockets, in which little or no quartz is found. 3. Manganiferous quartz veins very low in silver and gold at the surface which, with depth, become important silver veins containing subordinate amounts of gold. These veins have a quartz gangue with an abundance of Phodochrosite. The silver is associated with small amounts of sphalerite, galena, and pyrite; fluorite also is present. The Eagle is the only mine that has been developed in the manganiferous quartz type of vein. It was discovered ill the fall of 1582, but little more than assessment work was done on the property for a number of

Jan 1, 1923

By Francis N. Flynn

Many excellent papers, descriptive of the milling and smelting of every kind of commercial ores, the refining of virgin metals, the casting into various shapes demanded by the trade, the rolling into shapes best suited to the factory machinery and the making of composition alloys to suit every requirement have been issued by the many technical societies dealing with non-ferrous metals. It is a wonderful collection of papers, of which the mining and metallurgical engineers may well be proud, but strange as it may seem, metallurgists in general appear to take the stand that when they have delivered suitable alloys to the foundry and rolled products to the factory their duty to write papers has ceased, at least in so far as the A. I. M. E. is concerned. Still we read in the daily papers that the mining companies are absorbing metal-manufacturing industries. The purpose of this paper is to describe the reclaiming of non-ferrous scrap metals at manufacturing plants, taking as an example the automobile industry. Collection and Disposition of Scrap Until about five years ago, much of the factory scrap, with little or no preliminary treatment, was sold to secondary-metal smelters. Of late years the factory salvage department has become an important part, of the plant in reclaiming everything of value and incidentally does much of the work formerly done by the smelters. Like most good things, it is sometimes overdone, and much work is done at the factory with inexperienced men that could be done much better by experienced skilled labor at the custom smelting plants. Employees of the salvage department collect the waste products in all departments at the source and in that way avoid much contamination. Every reasonable precaution is taken to keep the scrap clean. It is hand-sorted, cut, burned, magnetized, concentrated, separated or compressed, as the case may be, preparatory for re-use in the plant or for selling to others.

Jan 1, 1930

By T. A. Rickard

In " The Genesis of Certain Auriferous Lodes "* Dr. Don makes a reference to a curious vein-formation known as the "Indicator," which characterizes a portion of the Ballarat mining district,, in Victoria, Australia. During 1890 and again in 1898 I had an opportunity of making a few notes, which, although somewhat belated,t may be worth adding to the observations recorded in the Transactions of the Institute. The country of the Ballarat gold-field consists of the Lower Silurian slates and sandstones, which also enclose the reefs of Bendigo; but it is noteworthy that the successive anticlinal folds, and accompanying saddles of quartz, which distinguish Bendigo are not characteristic of Ballarat, the geological structure of which presents greater complexity. That part of the district known as Ballarat East became famous early in its history on account of the large nuggets which were found in the alluvium, and subsequently it became further known because of a peculiar persistent black seam, traversing the bed-rock underlying the alluvial deposits, which was found to be associated with rich bunches of gold-ore, not only in the gravel that capped it at the surface but also in the quartz-veins which crossed it underground. The name of " Indicator " was early given. In 1871 Mr. Morgan Llewellyn directed attention to it as influencing the distribution of the gold. In the government quarterly report for December, 1888,

Jan 1, 1901

By Northcutt Ely

A year ago the petroleum code was in effect, and Congress had before it bills with powerful backing designed to extend and put on a permanent basis the Federal authority impliedly recognized in the petroleum code. Those men in the industry who were convinced of the unconstitutionality of Federal regulation, who believed in conservation, and who were seeking accomplishment of a conservation compact among the oil-producing states, were at that time encountering difficulties in bringing about such an agreement. Since then there has been a shift in the center of gravity. Today, by virtue of the Supreme Court's Schechter case decision, the petroleum code is not in existence, the industry is not operating under an oil administrator, and the Federal-control bills are not on Congress' calendar. In view of what the Supreme Court has said in the Schechter case and the Hoosac Mills case about the local character of mining and manufacturing, the problem today is not whether the Federal Government or the State Governments ought to regulate oil production, but how effective we can make the devices that are available to us under the constitution for the conservation of the nation's oil resources. The interstate oil conservation compact ratified during the past year by Texas, Oklahoma, Kansas, New Mexico, Colorado and Illinois, approved by Congress, but not yet in effect in California, is the mechanism now at work. Interstate Oil Conservation Compact What is this interstate compact? The basic theory is simple and logical. It has four elements to it. The first point is that in order to effect the maximum recovery of our oil arid gas reserves it is necessary for some governmental authority to regulate the way in which those resources are taken out of the ground, so that the reservoir energy is efficiently used, and used equitably by the various owners of the pool. Second, that the state, as distinguished from the national government, possesses the police power necessary to protect the public interest and to protect the correlative rights of the common owners of the oil pool. Third, that the state governments ought to cooperate with each other through an interstate advisory commission so that orderly production in one state is

Jan 1, 1936

By H. J. Struth

Economic law was accorded considerably more recognition by the oil industry last year than perhaps ever before. While proration was undoubtedly given added impetus in 1931, and the list of proponents of unit operation was noticeably lengthened, predominant evidence plainly shows that the functioning of economic laws dominated collective efforts to reduce the excessive above-ground supply of petroleum. Crude oil production was reduced more than 48,000,000 bbl. last year; imports from other parts of the world were substantially lower; stocks of crude were drawn upon to the extent of nearly 48,000,000 bbl.; domestic gasoline demand increased 2 per cent—and yet, prices of petroleum and its products were at the lowest levels in many years. To say that the ills of the oil industry during 1931 were due to the general depression that was felt in all other lines is tantamount to attaching an air of uncertainty to a group of commodities that have been proved to be an ever increasing necessity, even in times of depression. TO say that the potential productivity of proven oil-producing areas has been responsible for the unsatisfactory state of affairs last year, and now, is to admit failure to carry out the principles designed to control production in accordance with the limits prescribed by demand. In fact, there is no reason why a large proven potential supply of oil should not be considered a valuable asset to the industry; an assurance against future needs; a stabilizing influence in building up confidence in the ability of the industry to supply this and future generations with fuel and lubricant requirements at reasonable prices. At any rate, an assured future supply of oil should be interpreted to the public to mean that the oil industry is a legitimate, progressive industry, and not a group of prospectors madly searching for "liquid gold." There has been a great deal of romance connected with the history of the oil business—so much that the public has come to associate the word "oil" with untold riches. However, the financial statements of 1931 will furnish conclusive proof to the contrary. Too much oil, too many refineries, too many filling stations, too much capital invested; these and other "too muches" and "too manys" have perhaps been given more publicity than necessary. We seldom hear these

Jan 1, 1932

By C. A. Pierce

STUDIES of roof and floor movement are of interest to those actively engaged in mining. This is especially true in the case of an entirely new area where there is no precedent for guidance. The potash deposit being mined is in the southeast corner of New Mexico, about 20 miles east of Carlsbad. The deposit was formed by the land-locked, shallow, Permian Sea that extended through parts of western Texas, Oklahoma, Kansas, southeastern Colorado, and eastern New Mexico. The saline deposits vary from 500 to 4000 ft. thick. Neither of the companies operating in this area has delimited its com-mercial ore bodies. As all production so far has been from Federal and State leases, the Department of the Interior and the State of New Mexico have a direct interest in the development and extraction of these ore horizons. The ore is composed of an intimate mechanical mixture of sylvite (potassium chloride) and halite (sodium chloride). It lies generally in a horizontal bed varying from 5 to 12 ft. in thickness, and has a cover of approximately 1000 ft., consisting of about 500 ft. of salt beds and 500 ft, of sediments. The immediate mine roof for several feet is principally salt with some potash and clayey material. The next 500 ft. above, from the standpoint of structure, may be considered rock salt with a few inter-bedded potash members. The upper 500 ft. is of sedimentary (Permian and Triassic) origin and contains several water-bearing formations with flows varying from 10 to 500 gal. per minute. This water intensifies the interest in convergence problems as the ore and surrounding for-mations are water soluble. Potash salt (sylvite) and rock salt (halite) are plastic minerals. Plasticity is defined as a "property of solids by virtue of which they hold their shape permanently under the action of small shearing stresses but are readily deformed, worked, or molded under larger stresses."1

Jan 1, 1938