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THE annual meeting of the Arizona Section was held at the Pioneer Hotel in Tucson on Dec. 10, 1951. Registration and ticket sales for the social functions started at 8:00 am and lasted throughout most of the day. There were 489 registrations, consisting of 216 members, 64 students, and 209 guests. Chairman Harrison Schmitt opened the Mining Geology Div. meeting and a short business session was held at which Dr. Charles Anderson of Prescott, Ariz. was elected chairman and Seton Williams of Tucson was elected secretary for 1952. Dr. B. S. Butler was program chairman with R. B. Mulchay as co-chairman at the technical program. Eldred Wilson spoke on Oxidation and Water Levels at Some Arizona Mines. George Kiersch spoke about Economic and Engineering Significance of Ground Water Localization in Limestones - Big Bend Country, Texas. Harrison Schmitt gave The Definition and Use of Terms in Mining Geology. These talks were followed by discussions. E. N. Pennebaker, A. D. Wandke, and H. Schmitt gave informal talks on foreign trips made during 1951, the meeting was then adjourned.

Jan 1, 1952

Discovery of a deposit of magnetite ore estimated at 3 million tons and of quality sufficient to warrant mining has been located near Reading, Pa. by the Bethlehem Steel Corp. Last January; the company spent nearly $400,000 for about 1750 acres of farm land which had been valued at only about $50 per acre. It is expected that a pilot shaft 18 in. in diam will be sunk some time this spring. The ore body, delimited by diamond-drilling by Sprague Henwood, is said to measure roughly 2000 sq ft and 1000 ft thick, beginning 1500 ft below the earth's surface. In a continuing search for strategic minerals, the Atomic Energy Commission expects to put eight to ten diamond drilling rigs into the area 11 miles southwest of Blanding, San Juan Co., Utah early this year. The Commission's primary objective is the Salt Wash member of the Morrison formation. Holes 140 ft deep are expected to be drilled, with solid bit drilling through overburden, mudstone, shale and sandstone overlying the area.

Jan 1, 1951

By Courtenay de Kalb

THE Exposed Treasure gold-mine has, for the past four years, been one of the largest producing mines of Southern California, its annual output having constituted 1 per cent of the total gold and silver production of the entire State. At the present moment the property is idle, owing to the large quantity of water encountered oil the lower levels, which will require the installation of a powerful pumping-plant before operations can be recommenced. Moreover, a prompt change in the character of the ore has occurred at water-level, which makes imperative an extensive campaign of development in the region of the unoxidized ores before a plant adapted to their treatment can be definitely decided upon. The character of the changes encountered in these deeper ores makes the geology of this deposit a matter of importance, not only for the immediate district, but for the desert region of Southern California in general, where many mines exist having in the oxidized belt conditions that, in many respects, resemble those in the Exposed Treasure mine. The deposit is situated in an apparently isolated butte about 2.5 miles south from the town of Mojave, on the Mojave desert; The butte, though apparently isolated, is in fact geologically part of an extinct volcano, known as Soledad butte, which rises out of the plain 1,5 miles SW. of the mine, to an altitude of 4,650 ft. above sea-level. Other buttes also rise from the desert plain toward the south and east, and again to the westward, all being closely related geologically to Soledad butte,-the whole constituting a single system as to origin and time. Since the end of the period of active volcanism in this region, there has been extensive denudation, the ancient plateau having been dissected during an epoch of apparently exces-

Jan 1, 1907

By Jacques B. Wertz

Detailed structural studies in southeast Arizona have successively revealed (1) the local attitudes of individual fractures (with lateral and/or vertical displacements), (2) the patterns exhibited by groups of fractures, and (3) the trends and directions shown by fracture groups or zones on a regional scale. The results of the studies have been twofold: First, domes were locally determined from these fracture arrangements, even where other criteria failed; and, second, fundamental breaks brought out the breadth of the Texas lineament in southeast Arizona as well as major northwest- and northeast-trending fracture zones. Coincidence of one or several domes with the major intersections of fundamental breaks can be centers of important mineralization, as in the instances of Bisbee, Ajo and Morenci. THE OVER-ALL STRUCTURE OF ARIZONA A northwest-southeast trending anticlinorium has been suggested as the structural setting of Arizona. Starting in Triassic and culminating in late Cretaceous times, this deformation resulted from stresses of considerable magnitude with varying ratios of com pres sional and uplifting forces. However, the series of parallel flexures could just as well have been caused by isostatic movements involving dilation under tension with only incidental compression, as later emphasized by dike filling and block faulting (Fig. 1). The anticlinorial deformation, which is also suggested by the fact that the Pre-cambrian rocks to the southwest are all concealed by sediments, could be somewhat reminiscent of the conditions that affected the classical swarm of parallel dikes of wager.' ANALYSlS OF DATA As a first step in this analysis, all structural information obtained on such features as fractures and their relative displacements, faults, dikes, anticlines, synclines, and Precambrian and Laramide-Tertiary intrusives were plotted on maps along with structural trends inferred from aerial photographic mosaics. Next, the faults in southwest Arizona were classified according to time of occurrence and relative importance. The fault assemblages were then examined as to geometric or spatial arrangement and correlated with the occurrences of domes and existing Finally, the conjunction of fracture intersections and domes was analyzed and compared with locations of known ore deposits. Differentiation of Faults According to Time and Relative Importance: The faults encountered were grouped as follows: (1) Basin and Range faults, latest in time; (2) secondary faults; (3) primary faults; and (4) lineaments, earliest in time by inference. BASIN AND RANGE FAULTS- Generally concealed by alluvium, the Basin and Range faults are normal

Jan 1, 1969

By Arthur F. Taggart

MR. CHAIRMAN: Congratulations! Your four-ring milling show this year was a dandy. It cleared our minds, for a few hours at least, of what Hitler, Hirohito, the New Deal, and the tribe in the Treasury are trying to do to strangle American enterprise. We mustn't forget this, but it's a relief to get our thoughts away from it occasionally. GRINDING-There was a further contribution to the excellent work that the Allis-Chalmers laboratory staff has been doing for the grinding fraternity in compiling-and publishing-a carefully quantitative list of comparative resistances of ores and other materials to comminution (T.P. 1579, Bond-Maxson). A diagnostic accuracy of ± 10 per cent was claimed for estimates based on these figures. Are they really that good? How about some of you men in the field writing M&M about it?

Jan 1, 1943

By William R. Rumbold

WHEN I was in South Africa during the latter part of 1904, there were three known tin-fields, which may be called the Cape Town, the Bushveld and the Swaziland fields. THE. CAPE TOWN TIN-FIELD. This district is situated near Kuils river, 20 miles west of Cape Town, and 5 miles from Kuils River station on the Cape Town & Stellenbosch Railway. The deposits are in granite, intrusive in the Malmesbury beds, which are supposed to be of Silurian or Cambrian age. The granite, resisting denudation better than the surrounding shales,, has formed low-lying hills, the highest of which, the Bottlelary Berg, is 1,510 ft. above sea-level. , The rock consists of quartz, orthoclase feldspar and biotite mica; tourmaline is also present. The feldspar occurs in large crystals. The rock is generally decomposed on the surface, and the decomposition sometimes extends as deep as 100 ft. This formation-granite intrusive in Silurian shales-extends for many miles to the northeast, but so far as I know the Kuils River deposits are the only ones now known to occur in it, though probably further prospecting will reveal other deposits. This particular discovery was accidental;. alluvial tin being found in the course of boring for oil. The Kuils River Deposit. This comprises both lode and alluvial tin. The lode strikes N. and S., and dips about 30° E. into the hill. It is 5 ft. wide, and composed of dense white quartz, in which pinkish-gray cassiterite is distributed in large crystals. The vein also contains considerable quantities of wolfram. Fig. 1 is a rough plan of the relative positions of the lode and the alluvial deposit, the latter, as shown, following the course of a stream, while the lode crops out on the hillside

Jan 7, 1908

The cables brought the news last spring that the Institute had lost by death one of its most distinguished foreign members, Hjalmar Sjogren of Stockholm. For thirty-one years, Professor Sjogren had been one of our number. He was elected in 1891, joining the Institute at the time he was in the United States, in attendance at the Fifth International Geological Congress, which was held in Washington in the late summer of that year. Professor Sjogren was once more in America in 1906 and again in 1913, and on both of those visits his friends in New York had the welcome opportunity of extending courtesies to him. He was thus well known to a wide circle in our membership. His keen interest in the geology of iron ores brought him in touch with the many Americans who have studied them and who have been active in the important productive districts which he visited. Our Transactions contain (Vol. XXXVIII) one very important paper of seventy pages on the Geological Relations of the Scandinavian Iron Ores, which he contributed. Sten Anders Hjalmar Sjogren, to give his full baptismal name, was born June 13, 1856, and was the son of Anton Sjogren, a mining engineer, at the time in charge of the iron mines at Persberg, in the east and west iron-ore belt of central Sweden, about 160 miles west from Stockholm. The Persberg orebodies yielded magnetite and specular hematite from schists, with which limestones. were interstratified as well as the peculiar Swedish rocks called "halleflinte." The mines were also well known to collectors and students of minerals. While Hjalmar Sjogren was yet a lad, his father was advanced to the superintendency of a number of famous mining localities in this same district of Wermland. Paisberg, famous for its native lead, was one; and two others, Langban and Nordmarken, were among the most prolific sources of interesting minerals in all Sweden. In several localities, the pre-Cambrian limestones had obviously experienced the recrystallizing influences of intrusive igneous rocks and had been charged with the so-called "contact" minerals, which have found their way to the museums of the world. Anton Sjogren, the father, was a keen mineralogist and Hjalmar, the son, grew up in a favorable environment for receiving training and enthusiasms of the same sort. One is not surprised, therefore, to find Hjalmar Sjogren, in the long run, turning to mineralogy and geology as his final career.

Jan 1, 1923

The cables brought the news last spring that the Institute had lost by death one of its most distinguished foreign members, Hjalmar Sjogren of Stockholm. For thirty-one years, Professor Sjogren had been one of our number. He was elected in 1891, joining the Institute at the time he was in the United States, in attendance at the Fifth International Geological Congress, which was held in Washington in the late summer of that year. Professor Sjogren was once more in America in 1906 and again in 1913, and on both of those visits his friends in New York had the welcome opportunity of extending courtesies to him. He was thus well known to a wide circle in our membership. His keen interest in the geology of iron ores brought him in touch with the many Americans who have studied them and who have been active in the important productive districts which he visited. Our Transactions contain (Vol. XXXVIII) one very important paper of seventy pages on the Geological Relations of the Scandinavian Iron Ores, which he contributed. Sten Anders Hjalmar Sjogren, to give his full baptismal name, was born June 13, 1856, and was the son of Anton Sjogren, a mining engineer, at the time in charge of the iron mines at Persberg, in the east and west iron-ore belt of central Sweden, about 160 miles west from Stockholm. The Persberg orebodies yielded magnetite and specular hematite from schists, with which limestones. were interstratified as well as the peculiar Swedish rocks called "halleflinte." The mines were also well known to collectors and students of minerals. While Hjalmar Sjogren was yet a lad, his father was advanced to the superintendency of a number of famous mining localities in this same district of Wermland. Paisberg, famous for its native lead, was one; and two others, Langban and Nordmarken, were among the most prolific sources of interesting minerals in all Sweden. In several localities, the pre-Cambrian limestones had obviously experienced the recrystallizing influences of intrusive igneous rocks and had been charged with the so-called "contact" minerals, which have found their way to the museums of the world. Anton Sjogren, the father, was a keen mineralogist and Hjalmar, the son, grew up in a favorable environment for receiving training and enthusiasms of the same sort. One is not surprised, therefore, to find Hjalmar Sjogren, in the long run, turning to mineralogy and geology as his final career.

Jan 1, 1923

By J. PARKCEH CHANNING

Discussion of the paper of Lewis T. Wright, presented at the New Haven meeting, February, 1909 (Trans., xl., 492 to 495). J. PARKE CHANNING, New York, N. Y. (communication to the Secretary*):-Mr. Wright, in his introductory paragraph, says: " It is commonly believed by metallurgists that in copper-smelting, the copper in the slags, which is irreducible by continued smelting, is retained in the form of 'prills' of matte." On a recent visit to Greenwood, B. C., I was discussing with J. E. McAllister, the general manager of the British Columbia Copper Co., and the former metallurgist of the Tennessee Copper Co., this very question; and he held strongly to the idea that the copper in slag was in two forms-one portion contained in occluded matte and the other as an oxide. He believed that this same rule would apply to the silver in the slag. From my experience I am strongly inclined to agree with Mr. McAllister; and it appears quite reasonable that in furnaces treating oxidized copper-ores, and to a less degree in furnaces treating sulphide ores, there is always bound to be present a certain amount of copper oxide and silver oxide, which will behave like any base and get into the slag as such. We all know that in Arizona, in the early days, when it was customary to produce black copper, because the ores were nearly all oxidized or carbonates, and sulphur was scarce, the slags as a rule carried 2.5 per cent. of copper and seldom ran less than 1.5 per cent. of copper. The economic point was determined by the extra coke necessary to produce the reducing action. In connection with the extra saving in copper, Arthur L. Walker, now professor of metallurgy at Columbia University, and formerly general manager of the Old Dominion Copper Mining Co., at Globe, told me that with coke at $60 per ton it never paid him to make slags containing less than 2.5 per cent. of copper. *Received Oct. 8, 1909.

Feb 1, 1911

By D. J. Jr. McAdam

RESULTS of a general survey of corrosion-fatigue phenomena at the Naval Engineering Experiment Station were presented in five previous papers.1-5 In these papers references were given to the work of Haigh in 1917.6 The five papers mentioned gave a general survey of the behavior of metals when tested to failure under simultaneous corrosion and cyclic stress. As a result of this survey the fourth paper gave a tentative analysis of the corrosion-fatigue process. According to this analysis, if the initial stress is below the endurance limit but above the corrosion-fatigue limit, the corrosion-fatigue process is divided into two periods. The first period is the formation of pits. As the initial stress is below the endurance limit, the pitting is assumed to be due to corrosion, not to fatigue. The corrosion pitting, however, is not the ordinary pitting of stressless corrosion, but is an accelerated pitting due to the effect of the cyclic stress on the corrosion. As the pit progresses, both the actual stress and the effective solution pressure increase. The increase of actual stress is due to increasing stress concentration at the bottoms of the pits. The increase of effective solution pressure is due to the increase of actual stress. The mutual intensification of stress and solution pressure continues until the actual stress at the bottoms of the pits surpasses the endurance limit. The second period of corrosion-fatigue then begins. In this period the process is merely fatigue accelerated by the corrosion. The cracks advance at a continually accelerated rate until the specimen breaks.

Jan 1, 1930

By O. F. Thornton, D. L. Marshall

Results of the determination of the inter stitial water content of several core samples from oil reservoirs are presented. Data obtained by the capillary pressure method, which has recently been developed, are compared with water saturations measured in cores cut with oil-base mud and with values calculated from the electrical resistivity of the formation. The agreement between the capillary pressure and other methods, combined with the fact that similar agreement has been obtained by others, indicates that the capillary method properly applied yields results sufficiently accurate for most engineering purposes. In some cases, it may be possible to extend the utility of data obtained with the capillary pressure method by correlation of interstitial water saturation with more easily measured physical properties of the media. Introduction Several methods are in use for determining or for estimating the interstitial water saturation at given points within oil and gas reservoirs. The direct measurement of the water content of cores obtained with nonaqueous fluid in the hole is believed to be an accurate method under most conditions. The water saturation may be calculated by use of the resistivity curves of the electric log,' although this method is not applicable under conditions that exist in some reservoirs. Recently, a method has been developed and described3.' wherein the interstitial water saturation of cores is measured at a capillary pressure such that conditions existing in the reservoir are simulated. The purpose of this paper is to present data obtained by use of this latter method, and to compare the results obtained with determinations made by other means. Method The theory underlying the capillary pressure method applied to petroleum reservoirs has been discussed adequately in the literature by Garrison,2 Leverett,5 and Others.3,6,7 Briefly, and simply, capillary pressure is defined as the difference in pressure between two contacting fluid phases, such as oil and water. For the simplified sand, water and oil system illustrated in Fig I, the pressure difference can be stated as follows:6 where Pc is the capillary pressure in pounds per square inch, ? is the interfacial tension between oil and water in pounds per inch, r1 and r2 are the radii of curvature of the interface between oil and water in inches. Capillary pressure varies in a given reservoir with depth because of the greater density of the water phase as compared with oil or gas. The following equation expresses the difference in pressure between two points: p1- p2 - h?p/144 [2] where p1 — p2 is the capillary pressure difference in pounds per square inch, h is

Jan 1, 1947

By D. L. Marshall, O. F. Thornton

Results of the determination of the inter stitial water content of several core samples from oil reservoirs are presented. Data obtained by the capillary pressure method, which has recently been developed, are compared with water saturations measured in cores cut with oil-base mud and with values calculated from the electrical resistivity of the formation. The agreement between the capillary pressure and other methods, combined with the fact that similar agreement has been obtained by others, indicates that the capillary method properly applied yields results sufficiently accurate for most engineering purposes. In some cases, it may be possible to extend the utility of data obtained with the capillary pressure method by correlation of interstitial water saturation with more easily measured physical properties of the media. Introduction Several methods are in use for determining or for estimating the interstitial water saturation at given points within oil and gas reservoirs. The direct measurement of the water content of cores obtained with nonaqueous fluid in the hole is believed to be an accurate method under most conditions. The water saturation may be calculated by use of the resistivity curves of the electric log,' although this method is not applicable under conditions that exist in some reservoirs. Recently, a method has been developed and described3.' wherein the interstitial water saturation of cores is measured at a capillary pressure such that conditions existing in the reservoir are simulated. The purpose of this paper is to present data obtained by use of this latter method, and to compare the results obtained with determinations made by other means. Method The theory underlying the capillary pressure method applied to petroleum reservoirs has been discussed adequately in the literature by Garrison,2 Leverett,5 and Others.3,6,7 Briefly, and simply, capillary pressure is defined as the difference in pressure between two contacting fluid phases, such as oil and water. For the simplified sand, water and oil system illustrated in Fig I, the pressure difference can be stated as follows:6 where Pc is the capillary pressure in pounds per square inch, ? is the interfacial tension between oil and water in pounds per inch, r1 and r2 are the radii of curvature of the interface between oil and water in inches. Capillary pressure varies in a given reservoir with depth because of the greater density of the water phase as compared with oil or gas. The following equation expresses the difference in pressure between two points: p1- p2 - h?p/144 [2] where p1 — p2 is the capillary pressure difference in pounds per square inch, h is

Jan 1, 1947

By Thomas A. Steven

Most mineralized areas in the central San Juan Mountains, Colorado, are associated with the youngest subsidence structures in a large volcanic cauldron complex that formed concurrently with eruption of the surrounding ash-flow field. Two local types have been recognized: (1) fissure-vein deposits along faults characterized by relatively late movement, and (2) hydrothermally altered and mineralized areas associated with postsubsidence Fisher Quartz Latite centers. The first type has provided most production in the past; the potential of the second type has yet to be adequately tested.

Jan 1, 1968

By Wm. Reuben Webster

BRASS is an alloy of copper and zinc. The brasses (using this term to denote all useful proportions of the two constituents) are the most valuable and widely employed of all [ ] nonferrous alloys, because of their high resistance to ordinary corrosive agencies and the very wide range of properties that may be imparted to them by variations in the proportions of the constituents and by variations in mechanical treatment and heat-treatment. Fig. I shows the normal physical properties, as determined by standard tensile tests, of the series when in the annealed condition. Fig. 2 shows the effect of varying amounts of cold-working on an almost pure brass containing 70 per cent copper and 30 per cent zinc. Fig. 3 shows the effect of annealing at various temperatures on the same alloy. This effect is somewhat modi [ ] fled by the degree of cold-working to which a brass has been subjected, as shown by Fig. 4. A fourth test, which is empirical, has been found useful because of its simplicity -the hot hammer test. Samples Y2 in. in diameter and ¾ in. long are placed in a suitable furnace. These are withdrawn one at a time at successively higher tempera¬tures and are subjected to the blow of a drop hammer weighing 50 lb. with a drop of 4 ft. The percentages of' reduction in length of the cylinders are plotted against temperatures and give a comparative measure of plasticity at different temperatures. The results of this test on several

Jan 1, 1942

By M. R. Geer Olds, H. F. Yancey

THE increase in the number of coal-cleaning plants employing dense-medium processes occurring since 1946 is especially interesting when viewed historically. Both sand and magnetite were introduced as material for heavy mediums at about the same time, sand in the Chance process in 1921 and magnetite in the Conklin process in 1922, but from that point on their records diverge. The Chance process enjoyed a steady growth from its inception, whereas no additional magnetite plants were built in the United States for over 20 years. Then, following the close of the World War 11, magnetite was again introduced, this time with marked success. During the following years some 47 plants employing magnetite medium were built. This rapid growth of dense-medium cleaning has been concurrent with widespread adoption of full-seam mining on one hand and a return to a more competitive market on the other. At a time when changing mining practice has provided cleaning plants with dirtier coal and changing market conditions have simultaneously demanded a cleaner product, the industry has through necessity turned to improved preparation. The inherently greater sharpness with which dense-medium processes can separate coal from impurity is thus helping to hold the line against ever-increasing mining costs and at the same time assisting materially in retaining badly needed markets. Although dense-medium cleaning unquestionably offers a distinct advantage when the washing problem is difficult, other methods can provide almost equally high efficiency when the coal is easy to wash. Moreover, fine coal cannot yet be treated by heavy medium in a proved process, although the Driessen cyclone is in the pilot-plant stage. Most of the present types of dense-medium equipment have been in use only a few years, and the dearth of information in the literature concerning their performance characteristics is entirely understandable, Nevertheless this information is necessary if the process is to be intelligently applied to individual cleaning problems. Without data on the efficiency of a process in a particular type of separation, it is difficult to assess the advantage to be expected from it. Similarly, the role of particle size in heavy-medium separation is important in some cases, yet there is little published information on this aspect. To mention only one more of the numerous points on which essential information is lacking, the bearing of medium characteristics on performance has been discussed only in qualitative terms. It was with the hope of providing information on some of these points that the Bureau of Mines built a dense-medium pilot plant for cleaning coal at its Northwest Experiment Station in Seattle in 1950. The plant has been operated continuously since that time, and over 50 runs have been made on 7 coals exhibiting a wide range of washability characteristics. An idea of the magnitude of this work will be gained from the fact that examination of the plant products has involved some 600 float-and-sink separations and about 2500 ash determinations. A laboratory pilot plant is especially well adapted to investigate many aspects of performance because close control over test conditions can be exercised and because a large number of tests can be made rapidly. On the other hand, factors such as consumption of medium and other cost items can be investigated satisfactorily only in a commercial plant. Actually, the two forms of investigation should be complementary, with the laboratory work pointing the way for confirming tests in commercial units. Pilot Plant The dense-medium pilot plant employed for this work comprises a 24x30-in. drum-type separating vessel, a 12-in. densifier, a 12-in. magnetic separator, a 26-in. x 9-ft vibrating screen, and the necessary pumps and conveyors for handling materials. Arrangement of these units corresponds with the flowsheet used in most commercial plants, except that a thickener is not provided for the feed to the magnetic separator. Coal and refuse discharge from the separating drum to the vibrator, which is divided longitudinally down the center. Medium draining through the first 3 ft of the screen is recirculated directly to the drum. Sprays on the middle 3 ft of the screen rinse medium from the products, and the last 3-ft section is for dewatering. Dilute medium from the rinsing and dewatering sections is pumped to the magnetic separator, where magnetic solids are recovered. These are pumped to the densifier, from which they return to the medium-drainage sump by gravity through a demagnetizing coil. The drum-type separating vessel is a scale model of a commercial unit. Feed enters axially at one end of the drum just below the surface of the bath, and float material overflows through a circular opening at the other end. Particles sinking to the bottom of the bath are picked up by lifting flights bolted to the inner wall of the drum, elevated out of the bath, and sluiced to the vibrating screen. Baffles suspended in the bath prevent float material from entering the sink-lifting flights. About 8 gpm of medium is used to sluice the feed into the drum. An additional 15 to 24 gpm, depending upon operating conditions, is added through two pipes dipping into the bath behind the baffle on the side where the sink-lifting flights enter the bath. The bath available for separation is 2 ft long and 13 in. wide, giving an area of 2.08 sq ft. Depth of bath from the surface to the top of the sink-lifting flights, measured vertically below the axis, is 6 in.

Jan 1, 1954

By Russell S. Sage

THE electric motor has steadily replaced the steam and air engine for use in mine hoists, until today a new installation with other than electric drive is a rarity. Much existing steam-driven equipment has been changed over to electric drive. Driving power has grown in capacity since the initial electric unit rated 10 hp installed at Aspen, Colorado, in 1888, to 3000 hp and 4000 hp in the United States, and to 5500 hp in Canada-the largest in the Western Hemisphere. Electric installations now total in the thousands of units, a growth largely made possible by the development of large central electric-power stations and the extension of electric-power service to more mining areas.

Jan 1, 1949

By Harrison Souder

In view of the proposed visit of the Institute to Cuba this winter, the following brief sketch of the principal mineral deposits near Santiago de Cuba has been prepared largely from notes taken in February, 1903, during a visit to the mines then in operation in the province of Santiago de Cuba. Westward from Cape Maysi, the most eastern point of the island, the coast is rocky and uninviting. The usual course of the steamers is well in toward the shore, and the lines of stratification of the rocks can be distinguished clearly, the presence of iron or other ores being indicated by frequent blotches of mineral stain. One is impressed with the general rugged character of the southeastern coast-line,—an almost unbroken barrier of coral-limestone bluff's, full of caves and hollows, into which the surf rushes with a roar and bursts into tall fountains of spray. Beyond rises abruptly the Sierra Maestra range, whose sharp, peaked crest-line betrays its eruptive or igneous origin. From a height of about 800 ft. near Cape Maysi, this range gradually rises to the westward, attaining its maximum elevation of more than 8,300 ft. in the Pico Turquino, beyond Santiago. A general resemblance to the mountain-ranges of southern New Mexico is noticeable. At Daiquiri, 20 miles east of Santiago harbor, the extensive

Jan 1, 1905

By Milton E. Jennings

On May 11, 1977, the SAMARCO 508-mm (20-in.), 396-km pipeline was placed in service. This system represents the latest thinking in slurry pipeline design and is one of the main contributors to the viability of the SAMARCO project. This paper presents the background, description, and latest information on the system's operation. Special attention is given to the handling limitations of the slurry and to the unique hardware requirements.

Jan 1, 1982

By K. S. TWITCHEEL

THE different lines leading out from the vocation of a mining engineer are,' perhaps, the most' varied of all the professions. The expedition sent by Charles R. Crane of New York 'as a gift to the Imam Yahia, king of the Yemen, Arabia, was probably unique. Mr. Crane made a visit, in January,1927, to the Imam Yahia at Sanaa, capital of the Yemen. He was received with the utmost cordiality and respect, as his friend- . ship for the ,Arab world is famous; He was 'greatly impressed by the desire of the Imam to develop his country. The Imam stated that he had heard that there were minerals in his country and that he would like to secure engineers to advise him about them and other natural resources.. This seemed such a practical idea, and so greatly appealed to Mr. crane, that he offered to furnish an engineering 'expedition. Naturally the Imam gratefully accepted. This expedition was to study (as far as possible in 'the limited time) the natural resources of the ,Yemen, advise the Imam of what these consisted, and make suggestions regarding the most practical methods for their development. As agriculture is always such a fundamental part of a country's wealth, I first went to Indio, California, to study water-well drilling and the date industry, and eventually arrived at Hodeidah, the principal Yemen seaport, on Oct. 21, 1927.

Jan 1, 1929

[A Aall, Christian H., M49 B VP, Dir of Smelt & Refin, Am. Metal Climax Inc., 1270 Ave. of the Americas, N.Y. Aaroe, Stanley L., A54 B VP, The W. S. Tyler Co. of Can. Ltd., St. Catharines, Ontario, Canada Abalos, Toodulo Q., J57 A Prod Foreman, Lepanto Cons. Mng. Co., Mt. Province, Philippines Abbass, G., M55 P. O. Box 680, Hong Kong, China Abbitt, James M., A54 770 Sole Blvd., Bartow, Fla. Abbott, Raymond C., J59 3442 Greenwich Ave., Columbus 24, Ohio Abdullah, N. Y., J53 Dept. of Mines, Res. Div., P. O. Box 1016, Tiger Lane, Ipoh Perak, Malaya Abel, John F., Jr., J53- 100 Maple, Littleton, Colo. Abell, Leo M., M31 B Conc Supt, Phelps Dodge Corp., Morenci, Ariz. Abendroth, Harry E., A57 A Geol, Union Carbide India, 183 Brabourne Rd.. Calcutta. India]

Jan 1, 1961