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By R. J. Robbins

"For his exceptional ability both as an engineer and entrepreneur in the conception, design, and marketing of underground boring equipment; a technological development which has greatly improved the efficiency and safety of underground mining." Recipient of the 1984 D.C. Jackling Award

Jan 1, 1985

By T. G. Chapman

THE writer has carried on experimental work for several years with respect to the simultaneous dissolution of gold by cyanide and the adsorption of the dissolved gold on activated charcoal in ore pulps, followed by the recovery of the charcoal by flotation. The results of this experimental work have been sufficiently encouraging to suggest a new process based on the principle of simultaneous dissolution and adsorption of gold, applicable to certain ores and tailings that cannot be treated to advantage by countercurrent decantation or filtration. Applications for patents have been filed and The Dorr Company, Inc. has the exclusive right to license the use of the process. The purpose of this paper is to describe such a process, state its possible advantages and immediate field, and give some results obtained on a laboratory scale. EARLY EXPERIMENTAL WORK In the early stages of the experimental work attempts were made to precipitate soluble gold from cyanide solutions with zinc and aluminum in ore pulps followed by flotation of the precipitated gold, but since the results were not promising enough to continue with these precipitants attention was directed to carbon. The first experiments with carbon comprised the addition of cyanide and alkali to the ore pulp, the addition of carbon at or near the end of the dissolving period, and the recovery of the carbon by flotation. With this method of procedure the assumption was made that carbon functioned as a precipitant of gold from cyanide solutions and as such should be added as are other precipitants, including zinc and aluminum; namely, at the end of the dissolution period. The assumption was then made that carbon functioned as an adsorbent, and that if such assumption proved to be correct, it could be added with success to the ore pulp at the time of adding the cyanide. The first experiment along this line was successful in that the feasibility of the dissolution of gold by cyanide and the simultaneous extraction of the dissolved gold by carbon in ore pulps was demonstrated, at least with respect to such treatment on a laboratory scale.

Jan 1, 1939

By Robert Glass Cleland

THE OUTBREAK of World War II found Phelps Dodge, thanks to both foresight and good fortune, in a position to increase production of its mines and factories to meet the insatiable military and domestic needs of the times, far beyond all previous records. With the timely completion of the expansion program at Morenci, the company's copper output rose to approximately 447 million pounds in 1942 and to over 478 mil- lion pounds the next year, compared to some 300 million pounds in 1939. To meet the civil and military needs for fabricated cop- per products, the Phelps Dodge Copper Products Corporation carried out an expansion program comparable in size to that of the Phelps Dodge mining operations. It built new plants, enlarged and reorganized those already in operation, multiplied the number of technical experts on its staff, adopted new methods and new machines for the new prod-

Jan 1, 1952

For the year ending February, 1923 PRESIDENT ARTHUR S. DWIGHT, District 0 NEW YORK, N. Y. PAST PRESIDENTS HERBERT HOOVER, District 4 WASHINGTON, D. C. EDWIN LUDLOW, District 0 NEW YORK, N. Y. FIRST VICE-PRESIDENT J. V. W. REYNDERS NEW YORK, N. Y. TREASURER CHARLES F. RAND NEW YORK, N. Y. SECRETARY FREDERICK F. SHARPLESS,. . . . . NEW YORK, N. Y. ASSISTANT SECRETARY PERCY E. BARBOUR NEW YORK, N. Y.

Jan 7, 1922

[PRESIDENT E. DEGOLYER, District 0 NEW YORK, N. Y. PAST PRESIDENTS J. V. W. REYNDERS, District 0 . NEW YORK, N. Y. SAMUEL A. TAYLOR, District 3 PITTSBURGH, PA. FIRST VICE-PRESIDENT GEORGE OTIS SMITH, District 4 .WASHINGTON, D. C.]

Jan 1, 1928

Mining examinations are of several kinds and the scope of the investigation depends in each case upon the purpose for which the examination is made. A formal examination of a developed mine is an expensive undertaking; from one to several months are allowed for the work according to the size of the property; many samples are taken; investigation is made of the geological features, including, perhaps, a topographical and geological survey of the surface; the metallurgical treatment of the ore is studied; finally, a determination of costs is demanded. Formal examinations are made for prospective purchasers or as a basis for the consolidation of several properties, and occasionally, in the owner's behalf, to verify the work of resident engineers, or to determine the readiness of a mine for equipment and the kind and capacity of equipment it shall receive. A formal examination of a mine should not be undertaken until a preliminary examination has shown that it is justified. It is regrettable that some engineers are in the habit of prosecuting long and exhaustive examinations of properties whose lack of merit should be, and perhaps is, apparent from the start, or of continuing their investigation long after an unfavorable result is seen to be inevitable. This wasting of a client's money is a species of trickery difficult to prove, and therefore the more contemptible. Preliminary examinations are precisely what the term implies, and are undertaken to determine the advisability of making

Jan 1, 1932

By W. H. Craigue

THE scope of this article covers only the mathematical principles involved in discounting to present worth future expected profits and it is believed answers definitely two questions, which were raised at a recent meeting of the Committee on Methods of Valuing Coal Properties, as follows: 1. The accumulative effect of carrying charges on the value of coal mines showing definitely the number of years beyond which the coal may not be mined at a profit and subsequent to which the possession of any unmined coal will be a liability rather than an asset. 2. The effect on the valuation of coal mines, in the presence of the carrying charges described in question 1, of an increase in plant capacity and production. In general, in considering these questions, it may be stated that the consideration of an increase in plant capacity and production follows as a matter of course after a determination has been made of the year beyond which no profits are to be realized (giving the carrying. charges accumulative effect, or in other words capitalizing the carrying charges, as shown hereinafter). For example, if it is determined that any coal that is unmined after 45 years will have no value or less than no value, the question immediately arises as to whether or not a plant should be constructed that would result in a yearly production great enough to extract the entire tonnage in a time less than 45 years, and if so the number 'of years less than 45 years that would, from a financial stand-point, be the most desirable, all under the assumption that the market for the product or the transportation facilities are such that the yearly production can be increased to the desired amount.

Jan 1, 1933

By J. B. Sellers, G. R. Haworth, P. G. Zambas

Rock mechanics research was carried out in the Anvil Points mine, Rifle, Colo., in the period 1964-1968, with the dual purpose of providing oil shale to the retorts of six major oil companies and to perform research on mining cycle operations to maximize extraction under safe conditions. An 80% extraction ratio within the mining area proved feasible. Test results provided data on optimum pillar and roof design. Studies of mine orientation showed that the mining headings should take into account the prevailing joint patterns and also the directions of the principal in-situ stresses acting in the region.

Jan 1, 1973

By Blake M. Caldwell, Thomas C. Poulter

A new approach to an old problem has made it possible to do in a a tively short period what has not been accomplished in the past three quarters of a century using strictly experimental methods. A theoretical study was made of the underlying principles whereby a jet is formed by a shaped charge and of the mechanism of the penetration of the target by that jet. It was found that there are more than 10, and perhaps as many as 15 variables affectin!? the performance of the shaped charge. Only a few calculations are necessary to show that it is physically impossible to investigate all of these variables experimentally. The shaped charge theory has been extended to include a previously little-understood mechanism in high explosive phenomena; namely, low order detonation. By superimposing a high order detonation on a zone already undergoing low order detonation, all appreciable improvement in performance is accomplished. The development of a design wherehy these phenomena are coordinated in such a way as to develop a jet which is tailored to meet the specific target requirement will be described in detail. The shortcomings or even impossibility of strictly experimental techniques will be illustrated by a discussion of the development of a special-purpose explosive charge. INTRODUCTION In an article appearing in the May, 1888 issue of Scribner's Magazine, Charles E. Monroe described his early experiments with gun cotton (Fig. 1) which led to his name being most fre-quently connected with our present-day shaped charge. Although the sunken letters or "cavities" in Mon- roe's gun cotton were not lined, they produced some penetration of an iron plate. The credit for the lined shaped charge, however, should rightfully go to Dr. R. W. Wood of the Physics Dept. of Johns Hopkins University, who was responsible for first discovering the fact that a metal liner in a cavity of explosive gave high velocity fragments and/or jets of metal. This discovery was made by Dr. Wood inadvertently while investigating an accidental death resulting from an electric blasting cap. He discovered that a jet of high velocity copper particles was ejected from the dimple

Jan 1, 1958

By A. J. M. Ross

Backfilling of stopes and other underground openings in the Homestake mine with sand tailings was undertaken primarily to reduce surface subsidence, which was wrecking much of the surface plant and a substantial part of the town, and to make possible maintenance of openings into the top of pillar stopes as mining progressed. The progress of this type of filling has been rapid and the results very satisfactory. Sand is now used in filling timbered stopes, shrinkage stopes, and abandoned drifts and crosscuts. A permanent pipe-line system for transporting sand tailings into the mine by gravity has been installed. The close filling of all stopes has resulted in important benefits other than the two major ones. The ore bodies in the Homestake mine occur as replacements in one distinctive layer of the metamorphosed pre-Cambrian sediments along a group of minor folds that together form a complex anticline that pitches at 35" to 40' to the southeast. The ore bodies are extraordinary for their magnitude. Widths of over 300 ft. have been mined and continuous ore has been followed for over 1200 ft. along the strike on some of the upper levels. Mining has been by shrinkage stoping with square-set mining of crowns and pillars. In the standard plan, shrinkage stopes 60 ft. in the direction of strike and the full width of the ore have been taken up to within 25 ft. of the level above. After filling, the crown has been mined by square-set methods, as have also the 40-ft. pillars between shrinkage stopes. In former days, when the supply of ore seemed inexhaustible, the mining of pillars was allowed to lag far behind because of the high cost. Many pillars were rather badly fractured on the level and in some places between levels. Coarse waste was used for backfilling all stopes, but in pillars it became increasingly difficult to maintain haulageways for the transportation of this fill over the top of the stopes as mining progressed. The cost of maintaining these crosscuts was excessive and in many pillars practically impossible. Therefore it became the practice to fill pillar stopes by tapping the back and sides of the stopes.

Jan 1, 1940

By A. J. M. Ross

Backfilling of stopes and other underground openings in the Homestake mine with sand tailings was undertaken primarily to reduce surface subsidence, which was wrecking much of the surface plant and a substantial part of the town, and to make possible maintenance of openings into the top of pillar stopes as mining progressed. The progress of this type of filling has been rapid and the results very satisfactory. Sand is now used in filling timbered stopes, shrinkage stopes, and abandoned drifts and crosscuts. A permanent pipe-line system for transporting sand tailings into the mine by gravity has been installed. The close filling of all stopes has resulted in important benefits other than the two major ones. The ore bodies in the Homestake mine occur as replacements in one distinctive layer of the metamorphosed pre-Cambrian sediments along a group of minor folds that together form a complex anticline that pitches at 35" to 40' to the southeast. The ore bodies are extraordinary for their magnitude. Widths of over 300 ft. have been mined and continuous ore has been followed for over 1200 ft. along the strike on some of the upper levels. Mining has been by shrinkage stoping with square-set mining of crowns and pillars. In the standard plan, shrinkage stopes 60 ft. in the direction of strike and the full width of the ore have been taken up to within 25 ft. of the level above. After filling, the crown has been mined by square-set methods, as have also the 40-ft. pillars between shrinkage stopes. In former days, when the supply of ore seemed inexhaustible, the mining of pillars was allowed to lag far behind because of the high cost. Many pillars were rather badly fractured on the level and in some places between levels. Coarse waste was used for backfilling all stopes, but in pillars it became increasingly difficult to maintain haulageways for the transportation of this fill over the top of the stopes as mining progressed. The cost of maintaining these crosscuts was excessive and in many pillars practically impossible. Therefore it became the practice to fill pillar stopes by tapping the back and sides of the stopes.

Jan 1, 1940

By W. Francis

Before attempting to describe the application of recently acquired knowledge to the classification of coal it will be as well to consider the objects at which a scientific classification should aim. Here one can not do better than to follow the example of Clarence Seyler,l by quoting from Huxley's "Classification of Animals:" "By the classification of any series of objects is meant the actual or ideal arrangement together of those which are like and the separation of those which are unlike, the purpose of the arrangement being to facilitate the operation of the mind in clearly conceiving and retaining in the memory the characters of the object in question. Thus there are as many classifications of any series of natural or other bodies as they have properties or relations to one another or to other things. But the statement of the characters of the class ... is something more than an arbitrary definition ... it expresses firstly, a generalization based on and constantly verified by very with experience; and, secondly, a belief arising out of that generalization—in other worda. the definition of the class is a statement of a law of correlation or coexistence . . . from which the most important conclusions are deducible." In that same sense writes John Stuart Mill, in the chapter on classification in his "Logic:" "The ends of scientific classification are best answered when the objects are formed into groups concerning which a greater number of general propositions can be made, and these properties more important, than could be made respectiug any other groups into which the same things could be distributed. The properties, therefore, according to which objects arc classified should, if possible, be those which are causes of many other properties, or, at any rate, which are sure marks of them." Now in the case of coal, the properties which have been used from time to time for classification purposes are the ultimate analysis, volatile matter, caking power, calorific power, burning properties, etc. Seyler has shown that there is a general law of correlation or coexistence between the ultimate composition and the other properties. The ultimate composition, therefore, of the natural series of bodies known as coal is the

Jan 1, 1930

By L. W. Eastwood

THE recrystallization and grain-growth phenomena of cold-worked metals have considerable industrial importance because of their role in the fabrication of metals. For this reason, and because of the general academic interest in the subject, these processes have received consider-able attention since the time of J. E. Stead's paper1 on The Crystalline Structure of Iron and Steel. There are considerable differences of opinion regarding the theory of recrystallization and grain growth and also differences in the observation of the modus operandi of the processes themselves. The value of many of the existing quantitative data on grain growth is decreased by the failure to distinguish between the grain sizes just after complete recrystallization and those resulting from coales-cence. For this reason also, the value of the diagrams of stable grain sizes, like those produced by Bass and Glocker2 and Czochralski3, is lessened in so far as an interpretation of the facts of recrystallization is concerned. It is hoped that the data presented in this paper will help to clarify and to simplify the facts relating to recrystallization, and at the same time will show that some of the present-day conceptions are unten-able. A paper on the theory of recrystallization, with additional data, will be completed in the near future by the writers.

Jan 1, 1935

By Charles A. Stickels, Edward E. Hucke

The dihedral angle, formed by the intersection of three interfaces, is often determined by measuring a sample of apparent angles of intersection seen on a random plane of polish, then comparing the exerimental distribution of angles to the distribution calculated by Harker and Parker. Statistical tests show that the latter distribution does not satisfactorily describe the population from which samples are drawn. It is concluded that the major reason for this discrepancy is the presence of a range of dihedral angles in all specimens. When reasonable care is used experimentally, random measuring error is unimportant. It is shown that measurements made on dispersed second-phase inclusions are subject to a systematic error depending on inclusion size, which can be minimized by using adequate magnification. A dihedral angle, calculated from a sample of observed angles as though a unique dihedral angle were present, is termed an "effective dihedral angle". Experience has shown that "effective dihedral angles'' are reproducible quantities, useful for characterizing samples. Methods of determining an "effective dihedral angle", establishing its reliability, and making comparisons between samples are discussed. THE authors have recently reported measurements of the dihedral angle formed by liquid-lead inclusions lying in nickel grain boundaries.' Di- hedral angles were measured by the statistical method first employed by Harker and parker2 and used subsequently by many other workers.3"8 Since a relatively high degree of accuracy was necessary in the authors' experiments, the reliability of this method of dihedral-angle measurement was examined. Briefly, this method of measuring dihedral angles is usually performed as follows. A multiphase alloy is prepared, equilibrated under conditions which allow sufficient interface mobility to establish equilibrium, quenched to room temperature, then prepared for metallographic examination. A large number of observed angles, formed by the traces of grain boundaries and/or interphase boundaries on the plane of polish, are measured at high magnification. If all orientations of interfaces in the specimen are equally probable, Harker and parker2 showed that the population of observed angles is described by a distribution function containing a single parameter, the dihedral angle, 8. certain properties of the population, e.g., the mode or median, have been calculated from this distribution function in terms of the dihedral angle.3, 9 Thus, if the mode or median of a sample is identified with the corresponding property of the population, a unique value for the dihedral angle is determined. One defect in this procedure lies in identifying the properties of a sample of observed angles with the properties of the population from which they are drawn. If one were to proceed in a more rigorous fashion, it would be necessary to find a function of sample properties which is an estimator of the dihedral angle. Then by determining the distribution function for the estimator one could set limits on the value of the dihedral angle. The most apparent obstacle to this straightforward approach is the complexity of the distribution function assumed to describe the population. In analytical form, the distribution function may be written:2, 10

Jan 1, 1964

By C. A. Wert, M. G. Coleman

The Zener relaxation in alloys in the a! solid-solution region of the Cu-Ni-Zn ternary system has bear investigated. Of the binary solid solutions that bound this region, Cu-Zn and Ni-Zn exhibit measurable Zener peaks whereas Cu-Ni does not. At constant atomic percent copper, the Peak height drops uni.forinly from the value in the Cu-ZTL binary to zero in CIA-Ali. The cariation of peak ternperatuve with composition is linear. At constant atomic percent zinc, the peak height in the ternary alloys goes through a large maximum as compared with the binary values. The temperature of these peaks varies smoothly with composition. The half-width of the peaks in the ter nary alloys, however, are much larger than those in the binaries. A large enhancement of the relaxation strength of the Zener relaxation in ternary Au-Ag-Zn alloys as compared to the relaxation strengths in Au-Zn and Ag-Zn binary alloys was observed by Firson and ert.' Since this effect was unexpected, the present study was devised to investigate whether enhancement of the Zener relaxation in ternary alloys is a general feature or is particular to the Au-Ag-Zn system. We have chosen the Cu-Ni-Zn alloy system for this investigation. Measurable Zener relaxations are observed in both the Cu-Zn and the Ni-Zn binary systems, but not in the Cu-Ni binary system. A large solid-solution region extends to large concentrations of zinc, making it possible to vary composition of the alloys over a wide range without crossing phase boundaries. EXPERIMENTAL PROCEDURE Two series of alloys were prepared. the first at constant atomic percent copper, the second at constant atomic percent zinc. The compositions of these alloys are shown by the circles in Fig. 1. The alloys were prepared by melting the individual components, each of which had previously been vacuum-melted, in an evacuated quartz capsule in an induction furnace at 1500 C. The capsules containing the molten alloys were quenched in water to reduce coring. Any individual melt which exceeded 0.001 pct weight loss was discarded. The ingots were swaged to a 50 pct reduction of area and annealed for 1 week in an evacuated quartz capsule to aid homogenization. The alloys were then

Jan 1, 1967

By Kenneth K. Humphreys, Joseph W. Leonard, Robert L. Llewellyn, William F. Lawrence

INTRODUCTION Cleaning fine coal sizes utilizing air currents in machines as the primary separating medium is called dry concentration or pneumatic cleaning. In 1947 approximately 18 million tons (16.38 million mt) of bituminous coal were cleaned by air machines; in 1965, 25.4 million tons (23.1 14 million mt); but in 1975, only 7 million tons (6.37 million mt). Table 11-1 shows the tonnages cleaned of bituminous coal and lignite in the United States by various types of equipment from 1938-1963. Table 11-2 shows only tonnages cleaned by pneumatic methods from 1964-1975. The decrease in tonnage to approximately 7 million tons (6.3 million mt) is due to a higher moisture content in the mined coal and the greater difficulty in cleaning the coal by air. There also was a definite trend to load raw coal at the mines, especially the slack which is the most expensive to clean due to the dewatering and drying requirements. While there have not been any applications of pneumatic cleaning in the anthracite field, its use has not been fully explored. The same is true for lignite and subbituminous coals.

Jan 1, 1979

By Arthur Phillips

DURING the past few years considerable interest has been shown in the study of fiber, and its effect, in wrought metals. Fiber has recently been defined as a "condition of parallelism of important lines or details in the structure. "1 Briefly stated, two distinct types of fiber are commonly encountered. One results from the alignment in the direction of working of constituents, more or less segregated, such as slag, oxides, carbides and dendritic formations. The second, and least understood, type is produced by working the metal below the recrystallization temperature in such a way as to develop a parallelism of the grains. This condition is readily recognized by the pronounced elongation of the grains in the direction of working. Under certain deformational treatments the grain fragments produced by cold working tend to orient in certain definite directions with respect to the axis of extension. Furthermore, even in metals that have been annealed after cold working preferred orientations may be present. It is perhaps logical to assume that such marked parallelism of structural elements would be manifested by directional properties in the metal. As a matter of fact, tests on many kinds of materials have shown differences in varying degrees. In recognition of this condition, propel design, for many purposes, places the fiber axis in such a way as to present the direction of maximum strength to the greatest applied stress.

Jan 1, 1931

By J. G. Puterbaugh

MARCH 31, 1922, undoubtedly will be long remembered as the ending of an important epoch in the coal-mining industry. On that date, contracts fixing the wages and terms of employ-ment at all anthracite mines and at approximately 60 per cent. of the bituminous mines of the country expired. For the past two years, the consuming public has been complaining bitterly against continued high cost of coal. Coal operators employing union labor have felt obligated to carry out contracts entered -into under the direction of the Bituminous Wage Commission appointed by President Wilson, and in order to do this, they have sacrificed millions of tons of business to non-union mines, and millions of dollars in wages that would have been distributed throughout unionized districts have been diverted to the non-union miners, many of whom never obtained the peak wages granted by the Bituminous Commission and others of whom accepted reductions early in 1921. Heretofore, wage contracts have overlapped as to expiration dates in different districts and renewals have had to take into consideration the competitive balance; the present situation is unique in that practi-cally every contract in the country expired on March 31, and the questions now confronting those responsible for the operation. of the coal mines of the country are: 1. Shall the operators that have heretofore employed union labor endeavor to continue contractual relations with United Mine Workers of America? 2. Shall they undertake to operate their mines with non-union labor? 3. Shall they encourage and endeavor to work out some plan of regulation or arbitration by a Government commission such as President Roosevelt appointed to settle the anthracite strike in 1902? 4. Shall the country give consideration to the demand of the miners that the coal-mining industry be "nationalized?"

Jan 5, 1922

By Charles W. Tandy, Wm. I. Weisman

Sodium sulfate is an important industrial chemical, being one of perhaps a dozen or so chemical commodities that are produced and consumed in the United States in quantities exceeding one million short tons per year. In recent years over half of the country's production of sodium sulfate has come from natural sources, whereas 20 years ago only 25% was derived from these sources. Production of natural sodium sulfate from various types of deposits is the main source of this chemical in Canada and Mexico, and probably in Argentina, Chile, and the USSR. [Table 1] illustrates the growth in production of natural sodium sulfate in the United States. Mineralogy and Physical Properties Sodium sulfate is widespread in occurrence and is a common constituent of many mineral waters, as well as seawater. Many of the saline or alkali lakes throughout the world contain varying amounts of sodium sulfate. In its natural form it is found as the hydrous salt, mirabilite, commonly called Glauber's salt, and as thenardite, the anhydrous variety. The largest quantities occur in the form of mirabilite. Sodium sulfate is found in varying degrees of purity, from theoretically pure efflorescent crystals of mirabilite to combinations and admixtures of other salts and impurities. It is a common constituent of some brines, and it is from this source that much is extracted commercially. Sodium sulfate is also found combined with other compounds, such as the mineral glauberite, the double salt of anhydrous sodium and calcium sulfate, and blödite, the double salt of sodium sulfate and magnesium sulfate. While these and other minerals containing sodium sulfate are not economically important, they are of interest because of their frequent occurrence. The reader is referred to other publications (Cole, 1926; Dana, 1932; Grabau, 1920) for descriptions of these minerals. Only the two economically important minerals, mirabilite and thenardite, will be described herein. Mirabilite, Na2SO4 • 10H2O, contains 55.9% water of crystallization. It is noted for its efflorescence or spontaneous loss of water. On

Jan 1, 1975

By Charles Goodale

THE principles and theory on which the U. S. mining law of 1872 was based are well understood, and have been discussed at great length by many writers. The papers by Dr. R. W. Raymond1 in the Transactions of the American Institute of Mining Engineers have covered the subject very fully, with explanations of practical results in many adjudicated cases. It is believed that the following instance of the application of the law in recent years will have some weight in a discussion of proposed changes in our mining laws. The litigation between the St. Louis Mining & Milling Co., and the Montana Mining Co., Ltd., a British corporation, over portions of the Drumlummon lode covered more than 20 years, and resulted in a judgment for damages in favor of the St. Louis Co. of such an amount that the Montana Co. declined to pay the judgment, and therefore lost the entire property. The Drumlummon lode claim in the Marysville district, Mont., was located in 1876 by Thomas Cruse. When he staked out his claim, he assumed that the discovery on the Drumlummon vein, and another showing of mineral about 200 ft. distant, were on the same vein, and the center line of the claim was given a course of N. 57'2'E. Development of the Drumlummon vein soon showed that its strike was about N. 15 E., and that the other outcrop was on the North Star lode; so it was inevitable that the Drumlummon vein would cross one or both side lines of the location, and the Montana Co. found it advisable to acquire adjoining claims on both sides of the Drumlummon, in order to avoid possible litigation over apex rights. They bought the Marble Heart, but would not purchase the Hopeful (see Figs. 1 and 2), at the terms proposed for the reason that exploration in the Cruse level had shown the vein to be barren in that region. The owners of the Hopeful were sinking an incline from that claim in 1889, and the Montana Co. enjoined them, contending

Jan 5, 1914