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By Ronald L. Gibbs

IN THE BEGINNING Contrary to popular myth, the personal computer can trace its roots back to a time before 1981 and the IBM PC. The seeds of the personal computer revolution were probably founded in 1975 with the release of the Altair (kit) personal computer, first advertised in Popular Electronics. June of 1975 marked the beginning of the Homebrew Computer Club in San Francisco. The founding membership list of the Homebrew Club now reads like a "Who's Who" of those involved in the early development of the personal computer industry. The Apple I computer was created by Steve Wozniak in early 1976 from the newly manufactured MOS Technology 6502 chip. It had 4,000 bytes (4K) of Random Access Memory (RAM] memory, a revolutionary amount of memory in 1976. Another early pioneer, the Commodore Pet computer, was another 6502 machine, but with 8K of memory. Tandy Corporation made its name in the hobby industry with leather kits. They embarked on a new path with the production of the TRS-80 line of personal computers. Most were based on the Z-80 chip, but again, were memory limited. A number of other Z-80 based systems followed later, including the Osbourne and the KayPro Computers. These systems were based on the Digital Research CP/M operating system and had a maximum of 64,000 bytes of memory (64K). The Apple I1 Computer appeared in 1977. Newer models of the original Commodore Pet and an Atari computer followed. These machines were also limited to 64K of memory addressing, and the early models typically shipped with only 16K, 32K, or 48K of memory. The Z-80 and the 6502 were the first truly commercialized CPU chips touting boxes with key- boards, monitors (sometimes a TV), and the ability to expand (peripheral slots for serial communications, centronics parallel communications, etc.1. They all shared one technology, audio tape as a storage media. The use of a portable tape recorder provided inexpensive, if not always reliable, magnetic storage. The tape recorders were typically finicky and required patience to use. Adjustments to the volume control were often needed to find "just-the-right" setting for loading or saving information. This kept the personal computer from being accepted in many markets, and gave it a reputation as a hobbyist or experimenters' toy. In early 1979, Steve Wozniak finished the design of a floppy disk drive and controller. This was a revolutionary design which reduced the "then" standard number of controller chips from fifty-plus, to just eight. With the advent of an affordable floppy disk drive mechanism, the personal computer was about to gain respectability. From a business standpoint, it was now possible to save and reliably retrieve business information. It also provided a superior means of distribution for commercially created software. Commercial software became a commodity rather than an oddity.

Jan 1, 1993

To the industrial geologist, as wen as to the general or historic geologist, the possession of a reliable key to the true order or sequence of the stratigraphy or position of the various upper rocky envelopes of the earth's crust, is, equally, a desideratum of the utmost importance. Of similar value to the two groups of students is the possession of facts which throw light upon the relationships which subsist between the puccessive rock formation of different countries, especially between countries lying close to each other, or within the same great geographical division.But there is necessarily a fundamental distinction which marks the respective limits of the field of observations of the industrial geologist, and the purely historic interest of the general geologist. The former has a more definite though less extensive scope. The scope of the latter is wide and indeterminate. In short, the observations of the industrial geologist are, 'from a commercial or economic point of view, of a more practical character, and are, therefore, intentionally restricted to the study of all geological questions which throw light upon the rocks which yield products of economic value and only include the study of the character and history of other rocks, in so far, as they afford aid to the more perfect comprehension of the best manner in which materials of economic value are likely to be sought, and the best means whereby these products may be secured for the material advantage of the community. The motive of the general geologist-in most cases-is a love of the study of some particular branch or province of the geological field, and the fascination of opening a new volume in nature's library, and the hope of extending the realm of knowledge, however slight, are often sufficient, as a motive, to enlist the energy and life's devotion of the true brethren of the hammer, irrespective of considerations regarding the commercial utility of the pursuit.

By Robert B. Hopler

"The story of packaged explosives begins with the use of black powder (also called gunpowder) in mining. Although discovered in the 13th century, it was not until 1627 that the first records of use in mining is recorded. It took until the early 1800's before its use began in underground coal. Althougha free-running, granular material, its recommended (and safest) manner of use was for the miner to pour it into ready-made or onsite formed paper bags prior to insertion into the borehole. This was absolutely necessary in horizontal or upward-slanting holes."

Jan 1, 1991

By Stuart F. McTavish

Mechanically suitable grinding mills became available to the mining industry in 1908. Since then, mill operators have been searching for the best material and design with which to line the mills. These liner systems had to fulfill several criteria. Most important, they had to last long enough in an operating mill to protect its structure from the abrasive wear of the ore and the grinding media. In addition, they had to be capable of efficiently transferring the energy from the mill to the mill charge in order to facilitate the grinding process. And these liners had to be easy to install and remove. The first liners used were generally made of cast white iron, Hadfield manganese, unalloyed high-carbon steel and composites of steel and concrete or cemented in flint blocks or natural stone. In the early 1920s, pieces of solid rubber truck tires were used as emergency repairs for broken cast metal liners. Thus was rubber first introduced as a mill liner material. The first patent for rubber mill liners was awarded in 1921 to James Denny and Rolla Watson, both of the Coniagas Mine in Cobalt, Ontario, and to Dale Barnum of the Comstock Lode in Virginia City, NV. This original design was covered under US Patent No. 1470597. It had a fabric backed rubber that was bonded to the shell of the mill.

Jan 1, 1990

By V. J. Southey

"This paper reviews the history of Wabana Mines from 1892 to 1966, inclusive, in order to clarify the essential factors involved in the achievement of maximum mining efficiency and in the search for an acceptable product to satisfy changing market requirements. It outlines the progressive steps taken to mechanize both surface and underground operations, and forecasts anticipated performance, assuming certain major plans could have been implemented. Results of extensive research in the treatment of the complex ore are discussed. Selected processing alternatives are compared as to feasibility in a summary incorporating estimated capital and operating costs."

Jan 1, 1969

By Theodore R. Maynard

The history of foundation engineering in Chicago is a tale of innovation, made necessary in order to keep pace with structural technology which allowed taller buildings with heavier bearing loads, to accommodate a non-conducive geologic setting. The geology as it relates to foundation construction and underground construction in general is briefly described. A chronology of important events from the birth of Chicago to the present is presented. The impact of various construction techniques which were either initiated or refined to allow the growth of Chicago are discussed. Introduction The growth of Chicago resulting in today's high-rise high-density population center can be looked upon as a history of modern underground construction. The two major reasons which explain this are 1) It grew up during a period of rapid development in the Industrial Revolution and 2) Its natural geological setting needed a great deal of innovation for continuing growth.

Jan 1, 1991

By S. A. Luciani

"In 1957, an asbestos orebody was discovered in the northern sector of the Ungava Peninsula of the Province of Quebec, an area now identified as Asbestos Hill. The deposit is situated on a plateau 1700 feet above sea level and 42 miles inland from Hudson Strait. It is a bleak, iso. lated location of typical arctic environment. Fifteen years were to pass before the first shipment of ungraded fibre was made in 1972. These years we1•e occupied with field surveys and investigations, diamond drilling, engineering design, evaluation of investment and operating costs, and construction. The problems normally associated with mine development were further complicated by location, isolation, and the extreme cold and permanently frozen ground of the arctic regions. Unique to an isolated arctic operation are the organization of support facilities and services, procurement and retention of personnel, construction of access roads and airports, and scheduling of product out and supplies in during the short summer period of sea navigation."

Jan 1, 1976

By John Convey

This paper, a follow-up to an earlier study, gives the history of Canadian developments in mineral processing from 1921 to the fall of 1964. It deals extensively with comminution and flotation, and then goes on to cover the fields of gravity concentration, magnetic concentration, cyanidation, the processing of uranium ores, and instrumentation. Several outstanding examples of installations are given. The paper concludes with a discussion of present-day trends in mineral processing. Introduction T HE history of the developments in mineral processing in Canada from its earliest times to 1920 has already been published by one of the authors (1). The present paper is thus a logical follow-up to bring this history to date. From 1834 to 1920, mineral processing in Canada, as elsewhere in the world, was in its formative stage. This, however, prepared the ground for developments that have resulted in a mining empire from the Atlantic to the Pacific, a mining empire which could be said to be almost on par with that in the United States.

Jan 1, 1965

By Paul L. Russell

Introduction As the US and world population increases, so does the problem of supplying expanding energy needs. Early requirements worldwide were mostly met by abundant forest vegetation. Man's large scale use of minerals-energy resources is a fairly recent development. It occurred only during the past 200 years. Coal was the first mineral fuel to be used extensively. It was not a large factor in US energy production until the beginning of the 19th century. Petroleum and natural gas use is about 125-years-old. Electricity generation by falling water is about a century old. Atomic energy is only about 30-years-old. Extensive use of it is still in the future. Solar energy is in its infancy. Other energy sources such as wind, peat, and geothermal energy are minor and primarily of local importance. There were three main features of the fuel supply picture during the past 125 years. By 1900 coal replaced wood as the principal energy source. Since 1900, oil and gas have captured many coal markets. And after the mid-1970s, there was a resurgence of coal usage. (Figs. 1 and 2). Wood Until the advent of mineral fuels for energy, the major global energy source was wood. But populations increased and became centered in towns and cities. The problem of a sufficient energy supply first developed as nearby, easily obtained wood was exhausted. This problem became more acute as industries such as shipbuilding, smelting, and pottery making, became more widespread. Results of wood use as an energy source and building material are starkly evident in areas of the world where civilization is oldest. Entire forests were consumed and have never been replaced. In the US, wood supplied 90% of all fuel requirements until about 1850; and more than 50% until after 1880. By 1900, wood still supplied 20% of all energy uses. In the mid-1970s, energy costs increased, due largely to the oil embargo. This increase resulted in an increased wood demand for domestic heating. While large quantities of wood were being used, its share of the total energy market was still less than 3%. By 1983, wood was becoming increasingly scarce and more costly near most large US cities. Wind Wind powered ocean vessels for many centuries. Sailing ships were still common in 1900. Windmills provided an early, cheap energy source and continue to be used today on farms. Design and development of windmills for electricity generation is being conducted. Interest in wind power is growing worldwide where availability of wind currents warrants the investment. Also, US regulation requires power companies to "buy back" electricity generated by windpower in excess of that used by the windmill owner. Coal By the 1600s, England was producing, 900 kt/a (1 million stpy) of coal for heating and other uses. The first coal-fired blast furnace for iron smelting was developed in 1621. Coke-making was developed in 1755, and Watt invented the steam engine in 1769. Illuminating gas made from coal was introduced in London in 1800. During this same 200-year period, France and Germany developed coal production, but on a smaller scale than England. US, bituminous coal was mined near Richmond, VA, as early as 1748. Major bituminous coal-producing states in the early period were Pennsylvania, Virginia, Ohio, Kentucky, Illinois, and Maryland. West Virginia replaced Virginia as a major producer, when that state was formed in 1863. As the US expanded west, new coal deposits were found and exploited. Indiana, Alabama, Tennessee, Iowa, Kansas, Missouri, Washington, Colorado, Wyoming, Arkansas, Oklahoma (Indian Territory), Montana, New Mexico, and Texas had significant coal mining operations by 1900. Today the eight major coal producing states are Kentucky, West Virginia, Pennsylvania, Illinois, Ohio, Virginia, Wyoming, and Montana. These states accounted for about 80% of all coal (lignite, bituminous, and anthracite) produced in the US during the past several years.

Jan 8, 1984

By James S. Graham

Foundation pile driving hammers used in New York City in the past 100 years have been drop, steam, compressed air, diesel, and hydraulic. In 1992, the first hydraulic hammer in the New York City area was purchased by Norwalk Marine Contractors, Inc. from Junttan in Finland. It was bought because of its variable energy and ease of mobilization, not because of its higher transferred energy. Heller and Johnsen engineers instrumented hydraulic hammers on nine jobs. The measured transferred energy for the nine jobs was found to average approximately 80 percent. There is no clear consensus regarding the reasons for the hydraulic hammer being more efficient in delivering energy to the pile as compared to single-acting steam/air impact hammers. To minimize pile damage during installation, and to minimize footage overruns, an up-to-date version of the wave equation software that includes an efficiency value of 0.95 for hydraulic hammers is now used.

Jan 1, 2000

In this address I look back over the past 40 years of mineral exploration in New Zealand û essentially the period since the Second World War (ie since 1945). It was the period of my personal involvement, and indeed of the personal involvement of a number of you. Luckily it was aperiod of great interest and activity. In the previous 50 years, virtually nothing had happened, and it is kindest to draw a veil over that period. In the very important earlier 40 years (1855 - 1895) the New Zealand gold rush occurred. That must have been a fascinating, rewarding period, which has been thoroughly documented by better historians than myself. I will simply comment firstly that its mineral explorers (gold-prospectors) were very successful indeed, and found most localities of the minerals they sought, in spite of using very different methods from ours of today. Secondly, they were preceeded by one of Maori exploration, which searched for a much restricted list of minerals, but succeeded in finding virtually every locality we know of today. The explorers of both of these early periods were obviously highly successful, but, in the time available, I must restrict myself to the period since 1945. I am currently editing the effective up-dating of Gordon WilliamsÆ 'Economic Geology of New Zealand' (1974). It covers the last 12 years or so. Many of you are contributing to that volume û both as authors and as referees û and I would like to take this opportunity of thanking you all. Although this new volume excludes the energy field, many of us have been involved in it, and I am therefore including energy minerals in this review, as Williams did in 1974.

Jan 1, 1987

By A. A. B. Douglas

In this paper the origins of the mortar intruded concrete concept and its development and application in the construction of watertight bulkheads in South Africa are described. The events leading to the commissioning and execution of the West Driefontein Experimental Plug and the Virginia/Merriespruit Boundary Plugs, and their roles in the proving of the technique, follow. The development of the first Transvaal and Orange Free State Chamber of Mines Code of Practice for Mortar Intrusion Concrete for Underground Plugs and Bulkheads, Johannesburg, November 1962,is explained. The saga of the October 1968 flood and subsequent salvage of the West Driefontein Gold Mine is recounted. The paper concludes with mention of the validation programme carried out for the Placer Dome Western Areas Joint Venture and their South Deep water barrier programme.

Jan 1, 2006

By Robert B. Hopler

Emplacing explosives in the borehole by bulk methods is utilized today for about 35% of all of the explosives used in the United States. Although different from today's methods, some bulk emplacement has been utilized throughout the history of explosives. This paper provides an overview of the evolution of the industry from primarily packaged to primarily bulk materials and methods.

Jan 1, 1992

By Robert C. Horton

The Getchell Mine is located on the east flank of the Osgood Mountain Range in the Potosi Mining District, Humboldt County, NV. Mining in the area first began in 1883 for copper, lead and silver in skarn-related deposits. Tungsten was discovered in the skarns in 1916 and was mined sporadically until 1957. The first major discovery was made in 1933 when two Winnemucca prospectors, Edward Knight and Emmett Chase, found gold at the present site of the Getchell gold mine. In 1934, after a small amount of preliminary prospecting, the claims were purchased by Noble H. Getchell of Midas, NV. The Getchell Mine Inc. was organized and exploration and development work began on a broad scale. Major funding was provided by George Wingfield and investors he assembled. Laxalt described Wingfield’s immediate history prior to his financing of Getchell as follows.

Jan 1, 1999

By A. B. Parsons

Jan 1, 1971

By Edward H. Robie

Jan 1, 1971

Jan 1, 1971

By K. G. Thorne, M. J. McLeod, D. Hoy

"Throughout the Paleozoic, a variety of gold depositional environments were created in the New Brunswick segment of the northern Appalachians because of the complexity of arc and continental plate collisions and subsequent erosion of the orogen. In southwestern New Brunswick, recent exploration and research has focused on deposits and occurrences that can be broadly classified as intrusion-related, generated by late- to post-orogenic felsic to intermediate plutonic rocks emplaced during the Early to Middle Devonian. This work has led to the establishment of models for gold mineralization and guidelines for exploration in this area, which might also be applicable elsewhere in the southern part of the province and, perhaps, throughout the northern Appalachians. The deposits in the vicinity of Clarence Stream in southwestern New Brunswick exemplify this deposit type, and highlight the emergence of a possible major gold district in the region. Durant le Paléozoïque, une grande variété d’environnements aurifères ont été créés dans le segment néo-brunswickois des Appalaches du nord en raison de la complexité des collisions entre arcs et plaques continentales ainsi que durant l’érosion subséquente de l’orogène. Dans le sud-ouest du Nouveau Brunswick, les travaux d’exploration et de recherche récents se sont tournés vers les gisements et les indices appartenant à la classe des gîtes associés aux intrusions, générés par des roches plutoniques felsiques à intermédiaires tardi- à post-orogéniques mises en place au Dévonien précoce à moyen. Ces travaux ont permis d’établir des modèles de mise en place pour la minéralisation aurifère ainsi que des guides d’exploration pour ce secteur, lesquels pourraient aussi être appliqués ailleurs dans le sud de la province et, possiblement, dans l’ensemble des Appalaches du nord. Les gîtes aux environs de Clarence Stream dans le sud-ouest du Nouveau Brunswick sont un exemple de ce type de gisement, mettant en valeur ce qui pourrait devenir un district aurifère majeur dans la région."

Jan 1, 2008

By Ovidiu Pasca

The Phelps Dodge Miami Smelter utilizes four Hoboken converters to process molten matte from the Isasmelt vessel. This paper presents past and present improvements in operation, maintenance and process optimization, based on data collection, which has led to increased converter campaign life and copper throughput.

Jan 1, 2005

By Harry Asche

The last 12 months has seen the construction of the first Earth Pressure Balance (EPB) TBM excavated tunnel in New Zealand on the Project Hobson sewer storage tunnel for Watercare Services Limited, with the concurrent excavation of the second EPB tunnel on the Rosedale Outfall project for North Shore City Council. Together these tunnels involve a total length of 6km and follow an 8 year pause in TBM activity in Auckland. TBM performance on these two projects is thus of significant interest as there are four major tunneling projects totaling over NZ$8B being planned for Auckland, in similar ground conditions. Auckland?s bedrock is a weak sandstone/siltstone (East Coast Bays Formation), subject to infilled paleovalleys. The geology in the region has been significantly influenced by volcanic activity; 49 volcanoes are present within 20km of the city centre. The paper describes the design and construction challenges for the projects, including TBM performance, ?sticky spoil? management, and risks associated with basalt lava flows and two paleovalleys. Watercare?s Project Hobson also saw the successful implementation of a Geotechnical Baseline Report?one of the first uses of this type of document in Australasia. Rosedale Outfall is designed for high internal water pressures with varying hydraulic flows, with the risk of exfiltration explicitly addressed.