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By John H. Harden

The Koepe system of winding from shafts is the invention of Mr. Frederick Koepe, Manager of the Hanover Coal Mine, Westphalia, one of the collieries worked by Krupp, the well-known German ironmaster. The first trial of the system was made at the Hanover

Jan 1, 1889

By J. C. Marquardt L., J. A. Bratt, J. P. Hunt

The Quebrada Blanca copper/molybdenum prospect lies on a dissected plateau in the high Andes of Northern Chile. The Superior Oil-Falconbridge Group began exploration of the Property in 1977 under a joint venture foreign investment agreement with the Chilean government. Quebrada Blanca is a relatively high grade secondarily enriched porphry copper deposit. Primary mineralization occurred 38 million years ago and accompanied quartz monzonite intrusive. Early disseminated Primary mineralization was followed by hydrothermal mineralization, mineralized breccia, and post-mineral faulting. After supergene enrichment Quebrada Blanca was buried under late Tertiary gravels and then partially re-exposed in Quaternary time. During the past five years, a successful exploration program has developed an open-pit mining reserve, provided samples for bulk metallurgical testing, and located more than adequate supplies of water for future operations. The main orebody is amenable to conventional metallurgical treatment and contains more than 400 Mt (441 million st) of recoverable open-pit ore at about a 1:1 overall stripping ratio. The average millhead grade during the first six years of operations will exceed 1.5% Cu, plus recoverable molybdenum values. Several hundred million tons of additional reserves are available in the surrounding districts

Jan 1, 1984

By Charles A. Ashburner

The petroleum industry of western Pennsylvania and southwestern New York lias been one of phenomenal development. Greater and more sudden flucuations hare occurred in the price* of crude oil, and in all the collateral interests dependent upon its production, than in the case of any other mineral product which has been extensively exploited in the United States. This was more particularly so from the commencement of drilling for oil in 1859 down to the end of 1877. The experience gained during these early years has enabled the oil men to operate more intelligently since; the business is not now attended with the hazardous risks with which it is generally credited. The most important questions connected with the oil industry are those of (a) the oil-supply, and (6) the possible ultimate exhaustion of the field. Since 1876 my attention has been directed to the study of the statistics of the product of the oil regions. In January, 1880, in order to slow some interesting points connected with these questions, I prepared a graphic chart which was used to illustrate a lecture on petroleum delivered before the Franklin Institute. This chart was afterwards reconstructed in two distinct forms for publication in the census report. on Petroleum and its Products. These latter I have redrawn in a condensed form, and have extended them to include the statistics up to 1885, for publication in the Transac tions of the Institute, in conjuction with a map of the oil-re&'~IOIIS prepared by Mr. John F. CarII and myself. It is hoped that these illustrations will be found interesting to the members of the Institute, and of practical utility to oil-men, without any extended discussion, since it is my desire to make only such brief references to them and give such additional detailed facts as may serve to make the prominent features understood.

Jan 1, 1886

AT THE beginning of November, Mussolini had firmly established himself at the head of the Italian Government. He himself referred to the ascendancy of the Fascisti as the result of a revo-lution and bluntly informed Parliament that it was to vote, as a matter of form, as he ordered, or else be dissolved. One of the great consequences of these events in Italy was the impetus that they gave to simi-lar movements in other countries of Continental Europe. Another great event of the month in world affairs was the repudiation by the Turks of the Mudania agreement and their notification to the Allies that the latter must evacuate Constantinople and allow the Dardanelles to be closed. This had the effect of once more consolidating Great Britain, France and Italy in so far as this question is concerned, and there was prompt refusal to accede to the demands of the Turks. With the advent of November, both the United States and Great Britain were in- the throes of political contests. The result of the American election was a landslide against the administration and especially was it an expression of agrarian discontent and a declara-tion in effect that our domestic affairs are not good in spite of political representations that they are. In Great Britain, the Conservatives were put in power by a substantial majority in Parliament, but the fact that the Labor party became numerically the second party instead of the Liberals and that it polled about 40 per cent. of the total popular vote affords ground for misgivings, especially when it be considered that the Labor party was standing on distinctly socialis-tic and communistic principles. In Russia, there was a sitting of the Third Interna-tionale, to which Lenin in a speech made a quasi-confession of the failure of the communistic experiment in Russia. He admitted, moreover, that Russia could not industrially reconstruct herself without capitalistic help. Nationally the country is making progress. During November, the Far Eastern Repub-lic surrendered to the Soviet, which thus carried Russia back to the shore of the Pacific.

Jan 12, 1922

By George Smith

Introduction THAT an oil-land law is the most needed item in the proposed program of mineral-land legislation follows from the fact that Congress has never enacted a law really applicable to petroleum and natural gas. The action of Congress in 1597 in authorizing entry of oil-lands under the placer law, enacted 27 years before for the mining of gold in surface gravels, was plainly only makeshift legislation. Naturally the provisions of this placer law with its requirement of discovery as a prerequisite to location are nothing less than absurd when applied to petroleum deposits hundreds or thousands of feet beneath the surface. Other reasons which render oil-land legislation an urgent necessity arise first from the large acreage of lands believed to be valuable for their deposits of oil and gas and therefore withdrawn by Executive order from all entry pending the enactment of an appropriate law for their disposition-a withdrawal that has been specially ratified by Congress in the case of one State, Utah-and second from the exceptional importance of this resource to the nation, the large industrial worth of petroleum, and indeed its paramount value to the navy, not being suspected 17 years ago when Congress last legislated upon this subject. Mineral land of this type is also well adapted to serve for purposes of illustration in discussing the general principles that demand recognition in legislative reform. Most of the issues involved in the consideration of oil-land legislation are clean-cut, and essential differences of opinion will be seen to be based upon radical divergence in economic theory rather than upon conflicting views concerning unimportant details. For the last five years or more the geologists of the Federal Survey have discussed this subject and prepared memorandums and reports on .the various bills introduced in Congress. Most of the provisions suggested in the present outline have been under consideration at one time or another during that period, and many of the statements which follow can be said to represent the consensus of opinion among those of us who, both in the field and in the office, have given special attention to the public oil-lands.

Jan 6, 1914

By J. R. Eckel

It has long been known that mud properties affect drilling rate and that drilling with water is as much as six to .seven times faster than with mud. However, it is not known why drilling rates with mud are lower. Recent studies show what fluid properties govern microbit drilling rate and also provide a quantitative correlation of these fluid properties and hydraulics with microbit drilling rate. All the microbit tests reported in this paper were made with a low permeability (about 10 md) limestone. They were conducted at constant bit weight and rotary speed with varying fluid properties, flow rate Q and nozzle dinnteter d. The tests showed that (1) drilling rate in a given system with constant circulating rate and nozzle velocity is a function of the kinematic viscosity [viscosity /density, (cp)/ p (density)] of the drilling fluid measured at near bit nozzle shear rates; (2) the combined effect of fluid properties and hydraulics on microbit drilling rate is defined by a Reynolds number function (kQp/dp); (3) for the same kinematic viscosity, drilling rate is independent of solids content; and (4) for the same kinematic viscosity, drilling rate is independent of fluid loss. INTRODUCTION The fact that mudding up reduces rate of penetration is well known, but the reduction varies from well to well. The rate with mud may be 80 percent of the water rate or it may be as low as 15 percent. Since this reduction of up to seven-fold takes place under conditions of constant bit weight, rotary speed and mud circulating rate in a uniform formation, it can only be a result of the change in fluid properties. Previous work1-" both in field tests and in laboratory microbit tests) showed that drilling rate with mud is lower than with water (Figs. 1 and 2). Microbit tests also confirm, at least qualitatively, the field observation that drilling rate slows with increased pressure differential from borehole to formation (Fig. 3). The qualitative effect of drilling rate of bit weight, rotary speed and rate of mud circulation are also the same for the field and microbit rig. For these reasons, the industry generally accepts microbit results as being qualitatively meaningful in terms of field application.

By Charles S. Barrett, Hermann F. Kaiser, Robert F. Mehl

THE copper-silver system presents several points of special interest in the study of segregate structures. The system is simple eutectic, with limited solid solutions terminal with the pure component metals. The extent of solid solubility decreases with decreasing temperature for both the copper-rich and the silver-rich alloys, thus offering a possibility for the formation of Widmanstätten figures and also a possibility for aging after quenching. In contrast to the structures studied previously the structures in this system are unique in their origin, for one terminal solid solution will precipitate the other, and vice versa. In most of the other systems for which crystallographic data on the precipitation (or transformation) process are available, either intermetallic compounds or intermediate phases partake in the decomposition process; the absence of such phases thus distinguishes this system. The lattice structures of the two solid solutions are identical in type, differing in lattice spacing by approximately 10 per cent; because of this it seems difficult if not impossible to predict on the basis of present theory either the outward form of the precipitate or the lattice orientation relationships between matrix and precipitate. The eutectic temperature in the copper-silver system1 is 779° C. At this temperature copper dissolves 4.3 atomic per cent (7.0 weight per

Jan 1, 1935

JESSE L. JONES,* Pittsburgh, Pa. (written discussion?).-The most important criterion on which judgment of the quality of manganese bronze can be based is its freedom from lead. Not over 0.03 per cent. of lead should be present in a good grade of manganese bronze. While it is not questioned that manganese bronze with a high tensile strength and considerable ductility can be made .from materials that will give a lead content of possibly 2 to 3 per cent., there is no doubt that such material, while it may machine readily, will be found to withstand the impact test very poorly, and hence be unsuited for high-grade engineering work. When lead is present in considerable amounts, it forms in small pools in the alloy and the material has little strength at these points; in fact, such spots in the metal are equivalent to nicks in a test bar as far as their effect on tensile strength is concerned. A further objection to a high lead content is the ease with which it oxidizes and its consequent tendency to produce dross. A second characteristic of a high-grade manganese bronze is a low content of manganese. This should not exceed 0.05 per cent.; in fact, very many of the best grades of manganese bronze show, on analysis, only a trace of manganese or no manganese whatever. Manganese is a deoxidizer and its ready oxidation protects the other metals of the alloy; but if it is present in large amounts it will produce considerable manganese dioxide, which does not separate readily from the molten alloy and may produce black specks or drossy spots and render the obtaining of clean castings difficult. Aluminum should be present in a good grade of manganese bronze in only very small amounts. A content of 0.10 per cent. aluminum is ample. Larger amounts have a tendency to increase the shrinkage of the alloy, to give the ingots and castings a white, scruffy appearance, and to prevent the beautiful, golden, oxidization color characteristic of high-grade manganese bronze and a most excellent indication of quality. The work that the author of the paper has done is valuable from a con- servation standpoint, and it will supplement, in a marked degree, the advances that have been made by a number of manufacturers of manganese bronze in utilizing the turnings from this material. A number of firms have succeeded in making a very good grade of ingot metal from turnings and other light scrap, obtaining a tensile strength and elongation

Jan 4, 1919

By Alexander Anderson

In many oil fields a great variation in the production of adjoining wells has long been observed, and a certain proportion of dry holes, situated between prolific producers, has been regarded as normal without thorough investigation as to cause. Similarly, an occasional prolific producer has been found in a part of a field where all other holes have proven disappointing. Adjoining wells which showed an unreasonable difference in production have been surveyed, and the bottom of the poorest producer has been found to have lost sufficient vertical depth, through its drift, to diminish seriously its penetration in the oil zone. Again, the bottom of the good producer has been found to he more favorably situated by its migration up structure. Surveying of wells in California fields has shown many instances where the dry hole has drifted far off the structure to such a degree that no amount of deepening could ever convert it into an oil well. In other cases, edge wells have been found to drift into the field. At this time, in California, the surveying of oil wells is beginning to he accepted as a routine part of operating procedure. Some operators are surveying all of their new wells and, in some of the recently discovered fields, this practice is providing invaluable assistance in methodical development. The information that has been obtained from the surveying of many wells has convinced most operators that it pays to give careful attention to the drilling of wells. Chews are now usually cautioned to avoid reckless competition with each other. Whereas, formerly, certain companies demanded a large footage from their drillers, they now issue orders that a very moderate speed in drilling shall he maintained and that every care be taken to avoid practices likely to cause excessive deviation of the hole frorn vertical. As a result of these new instructions to drilling crews, a distinct decline in the average drift of the wells drilled by these operators has taken place and fewer dry holes are being drilled from good locations. To the petroleum engineer and the geologist, oil-well surveys provide the necessary data required for the construction of the correct cross-

Jan 1, 1929

By R. Taggart, D. H. Polonis, W. C. Gallaugher

In the Ti-Cu system, the a' phase can be produced over a wide range of alloy composition witJwut the retention of measurable amounts of the ß or ? phases. This paper reports on the decomposition of this hexagonal martensite phase front the standpoint of solute corzcentratiorz, tempering temperature, and coherency strain condition. The mechanism of precipitation during tempering comprises localized precipitation which is followed by discontinuous precipitation if sufficient coherency strains are present. The localized precipitation process in hypoeutectoid alloys is described by the generalized Johnson-hiehl equation and an activation energy of 46,000 cal per mole. In hypereutectoid alloys the corresponcEing activation energy is 51,000 cal per mole. The rate-controlling process has been proposed as the difision of copper along a' platelet interfnces. SEVERAL investigations have been reported concerning the kinetics of decomposition of the mar-tensitic a' phase in titanium binary alloys.' In the Ti-Mo system,' two modes of a' decomposition have been observed in the presence of /3 phase; one of these involves the precipitation of fine a from a', and the other involves diffusion across the a'-ß interface. In studies of the Ti-Cr system, Rostoker2 did not detect the formation of TiCr2 during tempering. In Ti-Ni alloys,3 the intermediate phase Ti2Ni has been found to precipitate directly from a' along the interfaces between plates. With the exception of the study of Ti-Ni alloys the previous investigations of tempering phenomena in substitutional martensites are mainly qualitative and do not present a detailed description of the precipitation processes. The following limitations restrict the correlation of the microstruc-tural processes and reaction kinetics during tempering in most binary-alloy systems. 1) A mixture of at least two phases characterizes the constitution of quenched alloys. 2) Difficulties have been encountered in obtaining uniform structures throughout quenched samples. 3) The reaction products, and in particular their morphology. have not been clearly resolved. 4) The martensitic a' phase forms over only a limited composition range for most titanium-base binary alloys. Gomez and polonis4 showed that the Ti-Cu system provides an excellent basis for investigating the tempering of a' over a range of composition without the complication of retained P or the transition w phase. In the present work the effects of solute concentration, tempering temperature, and coherency strain conditions are considered with reference to the over-all precipitation process in quenched alloys of the Ti-Cu system. Both microstructural observations and kinetic data are correlated to define the rate-controlling processes which govern the observed localized and discontinuous precipitation reactions. An earlier paper5 was devoted to a discussion of the modes of heterogeneous nucleation of Ti2Cu from the martensitic a' structure. The present paper will therefore emphasize the progress of the tempering reaction beyond the initial stages. EXPERIMENTAL METHODS The Ti-Cu alloys for this study were prepared by conventional arc-melting procedures. Chemical analysis revealed that the alloy buttons contained approximately 0.02 wt pct 0, 0.04 wt pct N, and within 0.1 wt pct of the intended copper concentration. The progress of the tempering reaction was followed by means of electrical-resistance measurements utilizing a Kelvin double bridge, microhard-ness readings with a 400-g load, and X-ray dif-fractometry patterns to reveal line-broadening effects. Metallographic specimens examined at magnifications greater than X1000 were shadowed with germanium to reveal fine structural details. Direct carbon replicas were prepared for the electron-microscopy studies. EXPERIMENTAL RESULTS Property Changes. The changes of microhardness that accompany the precipitation of Ti2Cu from a' are shown in Figs. 1 and 2. As the solute concentration increases the peak hardness, for a given tempering temperature, increases. In alloys of given composition the time to reach the peak hardness agreed with the time to attain maximum X-ray diffraction peak breadth, as shown in Fig. 3. The maximum hardness and the maximum line breadth increased with lower tempering temperatures, and the time to reach the maximum also increased. The a' peaks broadened during the initial stages of tem-

Jan 1, 1965

By C. N. Schuette

THE producers of this liquid metal call it quicksilver, while the consumer generally refers to it as mercury. It is one of he seven metals that were known to the ancients. These seven were gold, silver, iron, copper, quicksilver, lead, and tin. Other metals were sometimes accidentally alloyed with some of these, but it was not until 1490 that antimony, for example, was discovered and identified as a separate metal. It is not surprising that quicksilver should have been known in ancient or even in prehistoric times, as globules of the native metal often occur in the outcrops of the ore. Furthermore, the first man to build a fire on an outcropping of quicksilver ore would probably have found globules of quicksilver in the cold ashes of his fire after it burned out. The inability to pick up the globules with the fingers would excite interest and an attempt to gather it in shells or gourds to be exhibited and traded. The ore of quicksilver is the red sulfide, cinnabar, which has been mined and used as the pigment vermilion since before the beginning of written history. In recorded history, quicksilver is first mentioned in documents by Aristotle, 384-322 B.C. Theophrastus, in 315 B.C., credited the Athenian, Callias, with the invention of methods to beneficiate cinnabar in 415 B.C. In China also there are records antedating Christ which mention both vermilion paint and the fluid metal. From these early records, it seems certain that not only was cinnabar used as a pigment in those days but also that the metal was reduced from the ore and was used for amalgamation, for gilding, and for medicinal purposes. Quicksilver mining and metal-

Jan 1, 1953

By P. de Vitry, Oliver Bowles

THE conventional wire saw, introduced in the slate district of Pennsylvania by the Bureau of Mines in 1927, and used thereafter with remarkable success, consists of a three-strand steel cable having a diameter of 3/1 6 or 1/4 in. The equipment, methods used, and accomplishments have been described in previous reports.1-7 Similar wire saws have been used extensively in Europe, in quarries and in shaping blocks and slabs. During the period 1932-1937, competition in European marble quarries was keen, prices were declining, and orders were not abundant. When orders were received, there was generally an urgent call for speedy delivery. Because of the diversification of demands, it was impossible. to maintain in stock marbles of the color, size, and thickness called for,, therefore the material generally had to be fabricated after the order was received. The wire saw enabled stone mills to fill. such, orders promptly. With skillful handling, 7/8-in. slabs could be cut accurately and rapidly with this equipment. It was found, however, that, as the three-strand wire became worn, the cutting speed dropped rapidly and the cut became less accurate. To overcome these difficulties the junior author of this paper, after much experimentation, developed a new type of wire consisting of a single ribbon-shaped strand, twisted as shown in Fig. I. To ensure straight sawing, the twist of the ribbon is reversed from right to left and vice versa every 25 ft. The reversal of the [ ] twist is shown in Fig. 2. This is not a new feature; it has been used to advantage with the three-strand wire both in Europe and America for several years. However, some difficulties arise in splicing the three-strand reverse-twist wire, and the claim is made that cutting is less accurate as the wire becomes worn. To make an endless belt, the ends of the single-strand wire are brazed together with

Jan 1, 1941

By P. de Vitry, Oliver Bowles

THE conventional wire saw, introduced in the slate district of Pennsylvania by the Bureau of Mines in 1927, and used thereafter with remarkable success, consists of a three-strand steel cable having a diameter of 3/16 or 1/4 in. The equipment, methods used, and accomplishments have been described in previous reports.1-7 Similar wire saws have been used extensively in Europe, in quarries and in shaping blocks and slabs. During the period 1932-1937, competition in European marble quarries was keen, prices were declining, and orders were not abundant. When orders were received, there was generally an urgent call for speedy delivery. Because of the diversification of demands, it was impossible to maintain in stock marbles of the color, size, and thickness called for, therefore the material generally had to be fabricated after the order was received. The wire saw enabled stone mills to fill such orders promptly. With skillful handling, 7/8-in. slabs could be cut accurately and rapidly with this equipment. It was found, however, that, as the three-strand wire became worn, the cutting speed dropped rapidly and the cut became less accurate. To overcome these difficulties the junior author of this paper, after much experimentation, developed a new type of wire consisting of a single ribbon-shaped strand, twisted as shown in Fig. 1. To ensure straight sawing, the twist of the ribbon is reversed from right to left and vice versa every 25 ft. The reversal of the [ ] twist is shown in Fig. 2. This is not a new feature; it has been used to advantage with the three-strand wire both in Europe and America for several years. However, some difficulties arise in splicing the three-strand reverse-twist wire, and the claim is made that cutting is less accurate as the wire becomes worn. To make an endless belt, the ends of the single-strand wire are brazed together with

Jan 1, 1941

By Richard Moldenke

ONE of the little-known characteristics of cast' iron, which neverthe-less has an important bearing on results where accuracy in machining-is essential, is the ability of this material to ease up internal strains when. .allowed to remain quiescent for a more or less extended period of time. At seems as if the molecules in such a casting, by virtue of their "mobility,? can adjust their relative positions to an extent sufficient to overcome some of the existing stresses. The following instance will perhaps give a fair idea of the condition a casting may he in when just shaken out of the sand. A very large sheave-wheel, after shaking out, was taken' outdoors to be, cleaned and made ready for turning up. It was leaned against the side of the building, but before much could be done an arm tore apart with a loud report. Investigation showed that the sun had been shining on the upper rim, this adding a slight strain to those already existing within the arm and thus overbalancing the strength of the metal in tension. Had this sheave been kept under cover for a while, or at least until machined, the-strains., would have eased off sufficiently to allow the sun to look upon it without disaster. It will not be necessary to multiply examples. Every engineer knows the danger of water-hammer in pipe lines, particularly if the latter are of cast iron. Every mechanic knows, or should know, that it is not good to strike a fitting that is under steam pressure. It will be necessary to say a few words on the "internal- strains" in castings-the so-called "casting strains" we hear so much about. We all know that to get a casting reasonably true to the dimensions wanted requires a slightly larger pattern. The usual allowance for gray iron is 1/8 in. to the foot (1 cm. per meter) and ¼ in. to the foot (2 cm. per meter) for white iron (all dimensions). This reduction in length, breadth and thickness in a casting is erroneously called "shrinkage." It should be called "contraction," as for practical purposes. it is simply the difference .in dimensions of the casting red-hot and cold.

Jan 2, 1917

By Richard S. Culver

In spite of the widespread interest in rock bolt research, relatively little is known about the critical region surrounding the bolt anchor. In analyzing the stress distribution around an opening resulting from rock bolt support, it is commonly assumed that the bolt is fixed at a point far enough from the surface so that the anchor does not influence the performance of the bolt. Furthermore, a bolt anchor is assumed to per- form satisfactorily if it will hold the design load with a minimum amount of load relaxation, commonly called bleedoff. From the standpoint of the design engineer both of these assumptions are reasonable, but they ignore the fact that the extremely high stresses in the region of the anchor are capable of generating fractures in the rock. Lang1 estimated the bearing stresses for a slot and wedge anchor on a one-inch-diameter bolt to be as high as 125,000 psi. This paper describes a more thorough analysis of the magnitude of the stresses around the anchor and the nature of the potential fractures that might result. It should be emphasized that there are two types of anchor-associated fracturing which may occur. The more common form, particularly in soft rock, is severe localized crushing of the rock in the immediate vicinity of the anchor, which makes securing the anchor difficult and causes bleed- off. It is also possible to develop larger single fractures which propagate out from the anchor, affecting the strength of the entire rock mass. The formation of these larger fractures is of primary concern in this paper. In addition to estimating the contact stresses and pullout load for slot and wedge bolt anchors, Lang carried out an important study of rock bolt interaction which served as a basis for the experimental phase of this investigation. In the first phase of his tests, a plate of photoelastic plastic was compressed by a row of piano wire bolts, simulating the interaction of bolt stress fields to form a zone of uniform compression (Fig 1). To show the supporting effect of this beam, hr carried out another test series

Jan 1, 1968

ON Coal's Horizon one development rises above all others. That is the swift expansion of output to make Soviet Russia the largest coal producer on earth next to the United States. Few Americans are aware of the speed and extent of that expansion nor of the accompanying creation of a strong, resourceful mining machinery industry, nor of the extent and character of the mechanization of Soviet coal mining. Two initial clarifications are necessary for better understanding. First, we must keep in mind the sharp distinction between the Russian people and the communist Soviet dictators who rule them. The great mass of the Russian people are not members of the Communist Party as people here are Republicans or Democrats. They are not permitted to be members. There are, by various estimates, only 2 to 4 million members of that party in all Soviet Russia. The other 196 to 198 million are the victims of their tyranny and their terror. It is the activity of the Soviet rulers that concerns us here.

Jan 1, 1954

By G. M. Ellis

When developing a mineral processing facility, the mining company management and engineering staff should have some knowledge of the construction industry in order to work with the contractors involved as a team. Of course, the situation varies with the nature of the project and its size, but relations among owners, engineers, and contractors always will be enhanced if the mining company has a knowledge of three construction industry facets: (1) the makeup of a construction company, (2) the functions performed by its staff, and (3) the various types of contracts and tendering procedures available. There are several options open to a company wishing to bring a new mine into production from the grass roots, depending upon corporate structure, capabilities, and financial strength. A company that already employs a substantial engineering staff may elect to manage and perform the design requirements itself, and may handle some or even all of the actual construction work. But in cases where bank financing is required, the loan is often dependent upon adequate professional construction help being used.

Jan 1, 1978

By Charles R. Keyes

Discussion of the paper of Charles R. Keyes, Bi-Monthly Bulletin, No. 19, January, 1908, pp. 1 to 31. BERNARD MACDONALD, Guanajuato, Mexico (communication to the Secretary*) :-Mr. Keyes's paper is very interesting to me because of my personal experience with the development of the ore-deposits of Lake Valley. Seeing that many of the important facts connected with the early history of the development of these mines are either now unknown, or have become more or less distorted, and thinking that it would be interesting as well as valuable to have these recorded as a historical supplement to Mr. Keyes's elaborate paper, I present the following narrative: In February, 1881, soon after the Atchison, Topeka & Santa Fé railroad made connection with the Southern Pacific at Denting, N. M., the Lake Valley properties were brought to the attention of New York and Philadelphia capitalists by John A. Miller, of Silver City, N. M. At that time silver was $1.10 all ounce and silver-mining was very attractive. Vast fortunes were being made in Leadville and other Colorado camps, and Tombstone was pouring out its millions. Lake Valley, like all' other mining-camps in their early history, had its drawbacks, but the railroad, then passing within 14 miles of it, mitigated many of these. The camp lay in the foot-hills of the Black range, in which the Apaches had their stronghold, and raided, when it suited their convenience, the surrounding country, killing the prospectors and pioneer settlers and stealing their cattle. This band of Indians was joined by the outlaws and desperadoes from the frontiers of Texas, Arizona, and Mexico, who collectively defied the United States soldiers, restrained, as the latter were, by the mollycoddles from the East. The brutality of the Indian raids through Arizona and New Mexico in those days would scarcely be believed now, but they stain in deep

Feb 1, 1909

By Earl Oliver

THE term oil property, in this discussion, includes any type of easement or grant under which petroleum might be produced; it ranges from the mere right to drill on undeveloped wildcat acreage up to a fully developed oil property. The values of an oil property, as thus defined, vary widely according to the use for which it is intended, whether it is from the viewpoint of the speculator, the fraudulent stock promoter, the refiner and pipe-line owner, or the oil producer. The market value of a property is usually a combination of some two or more of these influences, and occasionally a combination of all of them, but we prefer to treat each viewpoint as distinct from the others, allowing the reader to make his own combination in such proportions as his inclination and property seem to require. This paper will treat the subject from the viewpoint of the oil producer. However, the other influences have such bearing on the cost of property to the producer and on the price he might obtain by its sale as to warrant brief discussion of them. Speculation, particularly lease speculation, is a parasitic growth on the oil industry, healthy enough, but of no economic value. The class of property usually dealt in for this purpose is the undeveloped lease. Its speculative value may have some relation to its probable productive value, but most frequently this value is the product of temporary excitement due to local development. The lease speculator, seeking out the trend of development or securing early information regarding a proposed test or a new discovery, immediately secures leases whose market value will be increased when the existence of such development becomes more widely known. His profits are purely unearned increment. Not proposing to spend money in exploration, he can afford to compete in purchase with the operator, who, in addition to bonus paid, must spend large sums in testing out his own acreage and that of the nearby speculator as well. It has a tendency to compel unduly high bonuses.

Jan 2, 1920

By H. J. Rose

Graphic methods have long been used to advantage in dealing with diverse phases of fuel technology and research. Not only are graphs convenient for presenting data and making calculations, but they are invaluable for deriving generalizations from a mass of data. This is particularly true when relationships are obscure and numerical correlation is poor. This paper describes a new form of graph, the Multibasic Coal Chart, which has been developed to facilitate the study and comparison of coals of all ranks from peat to anthracite on any moisture and purity basis. This type of chart is of unique value for coal classification purposes, since it permits a direct visual comparison of the results obtained when coals are classified by the various systems which have been proposed. Coals are highly variable in character as a result of wide differenees in original vegetal ingredients, degree of metamorphism, and nature and amount of associated impurities. For nearly 100 years, attempts have been made to devise a satisfactory method of classification, and many tables, formulas, ratios and graphs have been suggested. Many of the suggested systems possess considerable merit and have found a limited use, thus promoting a better understanding of coal. However, objections have been raised against each system, and none has received general adoption. When the various systems of classification are compared, it is found that there is an apparently almost hopeless confusion due to: 1. Serious lack of agreement as to the proper moisture and purity basis on which to classify coal. More than ten different bases have been proposed, each of which requires complete recalculat.ion of the analysis data used. 2. Lack of agreement as to what chemical and physical properties are most important and best to use for classification purposes. There is too little knowledge of the degree to which these properties can be correlated.

Jan 1, 1930