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Jan 1, 1887

By Richard L. Ash

7.3-1. Introduction. All phases of mining competent materials are affected directly by the results achieved from primary blasts. It is imperative that their design suit each particular set of mining conditions. In general, the round design must provide an adequate tonnage of material, properly placed with suitable fragmentation, to ensure that loading, haulage, and subsequent disposal or processing are accomplished at the lowest possible cost. Blasting rounds are designed by the proper application of cratering relationships developed for the single, concentric, confined explosive charge. Blasting for surface mining and most open-cut heavy construction, however, is characterized by the use of rounds, composed of a number of explosive charges with relatively long lengths, which are placed in benches with specific finite dimensions. Therefore, modifications must be made to the classical, single point-charge cratering concepts. It is the purpose of this discussion to outline the basic principles, significant variables, and procedures for their integration in the design of rounds that are applicable to conditions characteristic of surface mining. Because relatively insensitive blasting agents will be used in most instances, particular attention must be given to priming, control of confinement, and selection of charge diameters that ensure complete explosive-reaction execution. 7.3-2. General Considerations. The primary requisites for any blasting round are that it ensure optimum results for existing operating conditions, possess adequate flexibility, and be relatively simple to employ. It is important that the relative arrangement of blastholes within a round be properly balanced to take advantage of the energy released by the explosives and the specific properties of the materials being blasted. There are also environ- mental and operational factors peculiar to each mine that will limit the choice of blasting patterns.

Jan 1, 1968

By Ralph Hultgren

FEW phase diagrams of alloys composed of two transition metals have been adequately studied, probably because of the high melting points involved. Transition metals are the elements that have inner shells incompletely filled with electrons. They comprise groups IIIa to VIIIa of the periodic table, including more than half of all metals. We have chosen to study two systems whose comparatively low melting points allowed the alloys to be melted in a molybdenum resistance furnace. The nickel-palladium system proved to consist of a simple series of solid solutions, but iron-palladium manifested several remarkable features. The main characteristics of the latter diagram were decisively established, but lack of time prevented precise determination of phase boundaries. The gamma to alpha transformation in this system is unusual and warrants further study. Grigorjew1 determined the liquidus and solidus of the iron-palladium system by thermal methods. He found a minimum melting point, but no eutectic. He also found that palladium lowered the gamma to alpha and raised the gamma to delta transformation temperatures of iron, with a complete series of solid solutions existing between gamma iron and palladium. His measurements also indicated a compound or super-lattice near the composition FePd3. Jellinghaus2 found that annealing at 500° C. greatly increased the magnetic coercive force of an alloy of composition FePd. X-ray dif-fraction photographs showed that a tetragonal ordered phase had formed during the anneal.

Jan 1, 1939

As already announced in the notice of the 114th (New York) Meeting of the Institute, the ladies present met and organized the Women's Auxiliary of the Institute. All ladies of the families of members of the Institute-are eligible to this Auxiliary. The purpose and objects of the Auxiliary are well stated in the address of the President, Mrs. S. J. Jennings, in opening the organization meeting on the morning of Feb. 20, 1917. The address follows: "Ladies: Friends from far and near, on behalf of the Women's Entertainment Committee of the A. I. M. E., I extend to you a hearty welcome. "Most especially are we glad to see our friends from the Pacific Coast and the middle West, .whose royal hospitality to the members of the A. I. M. E. and their wives and daughters on their trips to California and to the Copper Country of the Southwest can never be forgotten. We are glad to be able in some small measure to return it.

Jan 4, 1917

By Irving B. Cadoff, Stojan M. Zalar

AgInTe2, CuInTe2, and all Proportions of CuxAg1-xInTe, forMed homogeneous single phase alloys after direct solidification from the nielt. X-ray analysis indicated a zinc-blel~de strzccture typical of the chalcopyrite compounds, and the electrical resistivity and Sccbeck coefficient values were in the semiconducting range. AuInTe, and AuxA4g,-, InTe, formed by what appeared to be a peritectic reaction (the thermal analysis curves showing more than one arrest) and were conseyue~ztly polyphase. Substitution of copper into AgIrzTe, resulted in a continuous transition in the room tenzperature Seebeck coefficient from the negative AgIzTe, to the positive CuInTe,. A zero coefficient was obtained at about Cuo.55 Ago.45 InTe, . The temperatzire variation was similar to that observed for the stoichiometric compounds, that zs, tendency towards "p" concEuction at elevated temperatures. The thernzoelectric figure of merit for the compo~uzds, as determined by the Putley -Harmnn method were in the range 10- to 10-7 "K-l; the thermal conductivities in the order of 0.15 cal per sec-cm-oK. INCREASED interest in semiconducting intermetallic substances is expanding much of recent research from simple binary compounds into polyatomic systems and solid solutions. Ternary compounds A' represent a covalent extension of the binary semiconductors Within the a tin isoelec-tronic series, Ag-Cd-In-Sn-Sb-Te-I, divalent cadmium atoms in CdTe are being substituted for by monovalent silver and trivalent indium atoms to form the compound AgInTe, . By cross-substitution with elements of other isoelectronic series, a great number of ternary compounds A 'B"'c? is possible. In all of them, however, a necessary though not sufficient condition for the covalent, semiconducting bond—that there be four sharing orbital electrons per atom—must be fulfilled. In AgInTe,, each silver or indium atom is tetrahedrally surrounded by four tellurium atoms, while each tellurium atom is co-valently bound to two silver and two indium atoms. Synthetic chalcopyrites A'B"'c~ were first recognized as potential semiconduct&rs by Goodman and Douglas.' Austin, Goodman, and Pengelly discuss preparation difficulties and some electronic measurements on AgInS, , AgInSe, CuInSe, , AgInTe, , and CuInTe,. Chalcopyrites A B c2v are mentioned in papers attempting to classify and predict semiconducting behavior of intermetallic compounds; on the basis of saturated tetrahedral sp3 bonds,3 by specific selection criteria,' and by crystallographic considerations."

Jan 1, 1962

By Malcolm V. Lowry

At Balmat in northern New York State, the St. Joseph Lead Co.'s 2100-tpd zinc mining and milling operation is utilizing a unique thickener in conjunction with conventional crushing, grinding and flotation methods. From 1930 through 1962, zinc concentrates went directly from flotation to the filtering, drying and loading facilities, all of which had to operate 24 hr per day. Wide fluctuations in tonnage also had to be accommodated due to variations in the grade of ore. Many problems were thus encountered in filtering and drying, but the cost of installing a conventional, large diameter thickener could never be justified. In 1963, after thorough investigation, an unconventional thickener that is unusual in several respects was installed at Balmat. The tank depth is 16 ft instead of the normal 8 ft. The rakes are raised and lowered by having the main drive gear located on a movable platform. Automatic controls are programmed to raise the drive platform and rakes during one shift of storage. During the next two shifts of withdrawal, the controls are programmed to lower the drive platform and rakes.

Jan 5, 1966

By AIME AIME

THE following paragraphs comprise such information as the Secretary has been able to obtain concerning the members and associates whose deaths have been reported. Further particulars or corrections of errors, and biographical data concerning deceased members or associates not already noticed in this way, are solicited. Pat Doyle was born in 1849. At the age of fifteen he entered the Civil Engineering College of Madras, India, and left it at seventeen, having achieved special distinction in mathematics, chemistry,. and geology. Before be was eighteen years old he was in charge of two of the most important Sub-Divisions in the Madras Presidency, where he had ample opportunities for acquiring a preliminary knowledge of his profession, which was his chief object in joining the Public Works Department. In 1867, his energetic measures saved the island of Seringham from disastrous inundation. At this period he began contributing to the press ; and after a varied practical experience he came into public notice again in 1876, with an article in the Colliery Guardian on Indian Mines and Mining. In 1877 he became a Fellow of the Statistical Society of London. He was a founder of the Straits Branch of the Royal Asiatic Society and a life member of the parent Society of Great- Britain and- Ireland, as well as a member of the Independent Asiatic Society of Bengal. In 1878-9 he was Chief Superintendent of the Public Works of Perak; was active in having the Associate Member Class added to the Institution of Civil Engineers; and became a member of the Society of Engineers of London and of the North of England Institute of Mining and Mechanical Engineers. In 1880 he went to the Southern Colonies and held several appointments in Australia, where he became a member of the Johnsonian Club, Brisbane, and the Queensland Philo-

Jan 5, 1908

By H. S. Munroe

THE native copper of Lake Superior occurs in the form of fine grains and scales, disseminated in small percentage through the copper-bearing rock ; and in large and small masses, from a few pounds to several hundred tons in weight. Formerly the bulk of the copper came from the mines of Ontonagon and Keweenaw counties, producing mass copper. At present these mines furnish less than one-tenth of the total product, and fully one-half of this is from a single mine. The masses are usually found irregularly distributed in nearly vertical fissure veins, and require much dead work in sinking, drifting, and stoping for their development. The risk and expense attending the working of these mines have made them, with few exceptions, anything but profitable. * Read at the Montreal meeting, September, 1880.

Jan 1, 1880

By L. J. Klinkenberg

It is pointed out that the current concept of pore size distribution is not unequivocally defined and that different methods aiming at a determination of such a distribution therefore do not lead to the same results. A pore size distribution should not be based on the idea that a core should, under all circumstances, behave as a bundle of straight non-interconnected capillaries of the same pore size distribution. This is illustrated by calculations and experiments on the displacement of miscible liquids. INTRODUCTION The introduction of the concept of pore size distribution has been an attempt to characterize the intricate geometry of the flow channels in porous media. As pores in a porous medium are interconnected it is impossible to describe exactly what is meant by a "pore" and, therefore, the term pore size distribution requires further amplification. In the visual method for the determination of pore size distribution "the pore" is considered to be the hole between the grains as observed on thin sections or on a polished surface of the rock under a microscope. In all other presently known methods,1,2 a displacement process is studied and it is ascertained what as- semblaae of straight cylindrical capillaries would show the same behavior. The distribution of the capillary diameters of this assemblage is said to represent the size distribution of the pores of the actual porous medium. From the foregoing it is already apparent that it is useless to try to decide which process or which method of investigation leads to a "correct" pore size distribution. To illustrate this further a displacement process in which a fluid is displaced by another miscible with it will be discussed and the results will be interpreted in terms of a pore size distribution. DISPLACEMENT EXPERIMENTS WITH MISCIBLE LIQUIDS OF NEARLY IDENTICAL VISCOSITY AND DENSITY Interpretation in the Form of a Pore Size Distribution If distilled water is displaced from a homogeneous unconsolidated sand pack by, for instance, a dilute solution of NaCI, the breakthrough recovery i.e., the amount of distilled water produced at the moment the first trace of NaCl can be detected in the effluent water, is between 95 and 100 per cent of the pore volume of the pack. This result can be understood by following in imagination the course of one particle of the liquid. Imagine a length, ?l, at the end of which a liquid particle has an independent chance of a renewed choice of pores of different diameters. In other words, the particle has a choice of traveling time, at, for any length ?l; instead

Jan 1, 1958

By C. G. Dunn

According to a recently suggested effect of silicon on the re recrystallization textures of high-purity Fe-Si alloys with (111)[112] type rolling textures, the recrystallization texture for a rolled (110)[001] oriented iron crystal probably should be entirely different from that of a (110)[001] oriented 3 pct Si-Fe crystal. Comparative studies of iron and 3 pct Si-Fe crystals, however, show that both have (110)[Ool] recrystallization textures when the rolling textures are the (111)[112] type after reductions in thickness of about 70 pct. Qualitatively the results from the iron crystal are like those of polycrystalline high-purity 3 pct Si-Fe and not like polycrys-talline high-purity iron. The large effect previously noted probably involves unknown impurities or processing variables rather than silicon itself. Some problems on experimental and analytical procedure for a spherical X-ray specimen, which was machined from a laminated composite of sheet specimens, are treated in the Appendix. A possible strong effect of silicon on the textures produced in cold-rolled high-purity Fe-Si (HPFe-Si) alloys during primary recrystallization and normal grain growth was suggested in a recent paper.' All the textures were far from the random-orientation type, but that of iron, or of Fe-Si alloys of low silicon composition, was entirely different from the texture of 3 pct Si-Fe. The same effect was noted for the textures obtained prior to normal grain growth, i.e., for primary recrystallization.2 It is the main purpose of the present paper to provide some clarification of this silicon effect. All the HPFe-Si alloys from zero to 3 pct Si, which were rolled by two or more stages separated by anneals, developed (111)[112] type rolling textures.2 Thus, there was no effect of silicon on the rolling textures. Earlier, Gensamer and Mehl3 also found no effect of silicon on the rolling textures of Fe-Si alloys; they obtained the Kurdjum.ow and Sachs (K-S) rolling texture for iron,4 which is characterized as the three ideal components: (100)[011], (112)[li0], and (111)[112]. There is a difference between the HPFe-Si multiple-stage rolling texture and the K-S single-stage rolling texture, but this is a variable processing effect. Of interest here is the fact that the recrystallization textures from (111) [llZ] type rolling textures were different depending on the amount of silicon in the alloy. There was a relatively strong (110) [001] component in the recrystallization texture of HP 3 pct Si-Fe5,8,2 but no such component in HP 0.6 pct Si-Fe, for example; the recrystallization texture for the latter was two (111) [110] type components and a (111) fiber component 1,2 Several publications have shown that a strong (110) [001] recrystallization texture is derivable from a (111) [112] type rolling texture for 3 pct Si-Fe crystals reduced in thickness by about 70 pct.7-10 Furthermore it appears that the strongest of these (110) [001] recrystallization textures occurred when the orientation of the crystal prior to rolling was (110) [001].7 Barrett and evensoon11 found that the rolling texture of a (110)[001] oriented iron crystal was (111) [llj]. Accordingly, it seemed desirable to determine whether a (110) [001] oriented iron crystal, upon rolling and annealing, would behave like the 3 pct Si-Fe crystal (or the polycrystalline HP 3 pct Si-Fe) and thus produce a (110) [001] recrystallization texture contrary to the suggested silicon effect, or would behave like the polycry stalline HP iron or HP 0.6 pct Si-Fe and thus produce (lll) [110] type components in agreement with a silicon effect. Briefly, the idea here involves the use of more precisely defined textures to obtain if possible better control of important variables that affect the recrystallization process. PROCEDURE A (110) oriented crystal of Ferrovac "E" iron (99.9 pct pure) was prepared in sheet form 0.080 in. thick with the [001] direction parallel to the long dimension of the specimen.'' This crystal was etched to 0.073 in. thickness (to remove some small included grains) and then was cold rolled in a 6-in.-diam mill to a final thickness of 0.022 in. The rolling was unidirectional except for an inadvertent reversal at 0.061 in. thickness. At this thickness, and also at 0.040 in., the rolling was interrupted for transmission Laue photographs. Molybdenum Ka-radiation filtered with zirconium was used in a transmission method1' to obtain the cold-rolled (110) pole figure. The sample was a 0.002-in.-thick section taken from the central region of the 0.022-in.-thick cold-rolled crystal. For the primary recrystallization study, cold-rolled samples were etched from 0.022 to 0.021 in. thick and annealed in hydrogen at 850°C. Primary recrystallization to a fine-grained structure, Fig. 1, was obtained in a 5-min anneal. Eleven sheets after

Jan 1, 1963

By G. L. Oldright

THE upper limit of richness of concentrates that can be smelted by means of the blast furnace without added diluents is fixed by the opera-tion of sintering. A sinter feed with normal gangue constituents, con-taining more than about 50 per cent of lead, tends to fuse; as a result, air does not come sufficiently into contact with the sulphides at roasting temperatures, and sulphur elimination is poor. Since most lead con-centrates now contain 55 to 80 per cent lead, it is necessary to add diluents to lower the grade of such sinter feed to about 50 per cent or less. This not only entails the expense of providing barren diluents when adequate diluents containing precious metals are not available but also appreciably lowers the capacity of the blast furnace to produce lead and increases slag losses. Attempts to desulphurize rich lead concentrates by methods other than sintering have not proved successful. Flash roasting, for example, converts much of the lead sulphide to lead sulphate rather than to oxide. However, this suggested the possibility that deliberate flash roasting of the concentrates to sulphate, followed by sinter roasting of the resulting product, might prove promising, particularly inasmuch as the elimination of sulphur from lead sulphate requires heat alone and not contact with atmospheric oxygen. The sintering of lead sulphate products has additional interest because important amounts of such products are now treated by lead smelters. Considerable quantities of lead sulphate are present in rich lead flue dusts and other by-products; lead-chamber sulphuric acid plants and other

Jan 1, 1940

The smoker, Monday evening, was an unusual success. It was held in the beautiful gold room of the Congress hotel, which was very elabo-rately decorated with American flags. More than 500 were present. The gallery was filled with ladies, who responded to the request of the song leader and helped in many ways to grace the occasion. The enter-tainment, was a varied one and was original with the Chicago Committee, which deserves great credit for the unusual success of the event. Al-though it was mostly funmaking, Dr. F. B. Cottrell and George S. Rice of the Bureau of Mines gave some very interesting talks, illustrated by flags and moving pictures, of their trip through Europe since the armis-tice. Mr. Rice's talk dealt particularly with the demonstrative coal and iron regions and Doctor Cottrell's was devoted almost solely to that part of his trip in Northern Italy where he was investigating the application of volcanic steam to power purposes. This steam is derived from boracic-acid springs and helium is secured as a byproduct.

Jan 11, 1919

Equilibrium in Lead Smelting. By S FREDERICK RAVITZ AND KENNETH E FISHER (Tech Pub 681, also Trans , vol 121 2300 words) Four liquids are ordinarily produced in lead smelting, namely, bullion, speiss, matte and slag To determine whether these exist together in equilibrium, the distribution of gold and silver among them was measured To crucibles containing similar mixtures of all four products, varying amounts of silver were added, and the crucibles were heated together under the same conditions for 3 hr, during which the charges melted and separated into four layers After cooling, these layers were assayed for silver, and the distribution coefficients, 1 e , the ratios of the concentration of silver in any particular layer to that in the bullion, were calculated In each experiment, each distribution coefficient was found to be constant, regardless of the amount of silver used Similar results were obtained using gold instead of silver The constancy of the distribution coefficients indicates that the bullion, speiss, matte, and slag exist together in equilibrium

Jan 1, 1937

By John P. Cosgro

The increasing use of internal furnace-boilers for power-plants at mines (doubtless due to the facility with which they may be installed by reason of their portability; the fact that they require no masonry setting, cast-iron fronts, buck-stays, etc., and practically no foundation; and the successful maintenance of their claim to equal and even superior economy, as compared with boilers of other types1) warrants this description of a method of remedying an injury which may occur, to such a furnace, even though it satisfies the requirements of the formula adopted by the U. S. Board of Supervising Inspectors of Steam Vessels.2 I refer to the sagging and deformation which may result from overloading the boilers for a considerable period—say, several days. This is sometimes unavoidable under the exacting conditions of continuous day-and-night service, and (in spite of all rules and precautions) the occasional careless or unskillful work of attendants. Such a trouble is by no means unknown on shipboard, where this type of boiler is so largely employed.

Jan 1, 1906

By S. R. du Toit, W. J. Oberholzer, M. I. Watson, D. G. Krige

The objectives, essential features and implications of the 'random' and 'deterministic' types of ore value surfaces are examined as well as the basic requirements for a satisfactory prediction model. The 'random' method used on the South African gold mines and based on observed auto-covariance patterns is briefly discussed as well as its justification in preference to the 'deterministic' approach. Various mathematical models for auto-covariance patterns are examined for the one-dimensional case. It is also shown that these patterns as estimated for ore values in certain mines agree closely for various sizes of ore unit. In two case studies the variations in gold, uranium and ore thickness covariance patterns are examined and compared with certain geological features established independently from sedimentological studies.

Jan 1, 1969

By L. A. Panek

Using an approach based on the theory of similitude, the author develops a general equation and related concepts that provide new insights to an old problem. The load-bearing capacity (strength) of a square, rectangular, or cylindrical prism of a brittle material such as rock, coal, or concrete is expressed as the mathematical product of a size effect, a shape effect, and a function of the mechanical properties (deformability, cleat/joint spacing, and friction) of the pillar, roof, and floor materials. Through an application of multivariate statistical analysis, the results of assorted tests (laboratory and in situ) and observations of failed pillars can be combined into a fundamental scaling equation, which provides a unified, consistent approach to the estimation of mine pillar strength. The form of the equation is sufficiently general to be able to incorporate refinements in the characterization of the structural parameters, as they become available through future analysis and experimentation. Analysis of the published test data suggests that pillar compressive strength (per unit of area) is proportional to the cube root of the pillar width, and that the height effect can be described as the superimposing of a variable size effect (characteristic of the material) on the constant width effect.

Jan 1, 1981

By G. V. Raymor, James T. Waber, I. Rex Harris

The lattice parameters of a series of fcc alloys of cerium and thorium were measured at 93 " and 298OK. Lattice parameters were also estimated for 171OK. Substantial deviations, y, from Vegard's law were observed. Although y was negative at the two higher temperatures, it was positive and large at the lowest temperature. A variety of models, which have been proposed in the past, were considered, and the calculated values of y were compared with the observed values. The best agreement was achieved with values computed with Friedel's equation. THE purpose of this investigation was to determine the effect of temperature on the lattice parameter and on deviations from Vegard's law of Ce-Th alloys. A large negative deviation from Vegard's law was first observed independently by Weiner, Freeth, and Raynor' and Van vucht2 in the room-temperature lattice parameters of Ce-Th alloys that form a continuous series of solid solutions. This observation was confirmed by Evans and Raynor. The allotropy of unalloyed cerium was reviewed recently by Gschneidner, Elliott, and McDonald. In two subsequent papers,5" these authors reported the influence of various alloying additions on the y= transformation, which occurs below room temperature. Although other rare earths tend to stabilize the double-hexagonal phase, thorium, plutonium, and scandium as solutes tend to stabilize the normal fcc phase. With addition of sufficient thorium as a solute, there is evidence that the formation of is suppressed and it becomes possible to pass continuously with decreasing temperature from the room-temperature phase to the fcc a phase. Thus there is a closed loop which is similar in many ways to the y loop well-known in ferrous alloys. A closed field also occurs in the pressure-temperature "equilibrium" diagram of unalloyed cerium. Because of interest in the effect of thorium additions and their influence on the a and phases, lattice-parameter measurements were made at low temperatures on the fcc phase for a series of alloys ranging from 10 to 90 at. pct Th. The results obtained at three temperatures are shown in Fig. 1. Evans and Raynors analyzed the deviations from Vegard's law in Ce-Th alloys in terms of changes in the occupancy of the 4f electron level in cerium,

Jan 1, 1964

No phase of the steel industry is more typical of its remark- able progress than is the evolution and development of the modern American blast furnace. The founding of the Institute in 1871 also marked the beginning of a new era in the pig-iron industry. The rapidly expanding westward development of the country, with its seemingly unlimited markets, gave rise to unprecedented demands for blast-furnace products. The manner in which the iron industry responded provides a fascinating chapter in the history of industrial development. Prior to this period, the iron industry of the United States, largely concentrated in the East, was based upon the consumption of local iron ores and local fuels, the latter predominately charcoal and anthracite. Small, isolated furnaces were located near scattered ore and fuel sources, and the completely integrated ironworks and steelworks were yet to be developed. In about 1860 exploitation of the newly discovered rich ore deposits in Michigan and the successful adaptation of blast furnaces to coke produced from coal of the great Pittsburgh seam in western Pennsylvania proved to be major factors in firmly establishing the general westward shift of the industry. But these were largely economic in character, and it was not until about 1870 that the aggressive, individualistic nature of the ironmaster asserted itself in no uncertain manner. No longer limited by relatively inadequate equipment and inferior raw materials, and spurred as well as encouraged by those who supplied capital for these new enterprises, furnacemen began to establish unheard of records in iron production. It is not surprising that Pittsburgh was the center of this new activity. Its tenor is best indicated by the following account :l

Jan 1, 1948

Jan 1, 1879

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