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By D. M. C. Valbom

The introduction of new diamond sorting technologies as well as additional manufacturers I vendors, has increased the equipment selection and combinations available for recovery flowsheet design. This paper describes the methodology used and the benefits realized in the design of recovery plants by ensuring a fundamental understanding of the advantages and limitations of the technology embodied in the equipment, a comprehensive knowledge of the ore body characteristics, and the effective matching of this information in combination with operational commercial requirements.

Jan 1, 2010

By Cyril Stanley Smith

ARCHEOLOGISTS, by use of the terms Bronze Age and Iron Age, indicate that metals have in the past determined the character of civilization. The relatively simple discovery by a primitive metallurgist that the addition of tin to copper both facilitated the production of castings and increased the durability of the product enabled hunter, warrior, and housewife alike to do things never dreamed of before. Similarly, the smelting of iron and the discovery of hardening methods greatly changed the arts of peace and war. Discoveries of low-melting-point alloys for joining and for making household utensils, and perhaps the adornment of a feminine form by sparkling precious-metal jewelry, have at times changed the destiny of a country. Bronze cannon, the cast and wrought iron Watt engine, copper transmission lines, and aluminum alloy aircraft, are cases of particular metals making possible the realization of an improved engineering design. Perhaps of the greatest influence of all upon civilization was the development of type metal. The rapid increase in the rate of dissemination of knowledge dates from the day that the technique of the pewterer was utilized in making rapidly reproducible and accurately sized letters for printing. It was not movable type, but metal type that was important, for metal castings could be made of identically the same shape and size at an enormous rate, and possessed excellent inking and wearing characteristics.

Jan 1, 1946

By T. Nagano

Mitsubishi Metal Corporation started the development work of a new process for continuous production of copper in 1961. After a series of experimental and semi-commercial operations, the first commercial plant of the Mitsubishi Continuous Copper Smelting and Converting Process was put into operation in March, 1974. The new plant, which has a design capacity of 4,000 metric ton copper per month, was built within the premises of Naoshima Smelter, replacing the old No.1 reverberatory smelter there. The SO2-rich exhaust gas from this new plant is blended with the off-gas of the No.2 reverberatory furnace for production of sulfuric acid and the overall emission of sulfur at Naoshima has been greatly reduced. The operation of the continuous plant has been satisfactory and several advantageous features of the Mitsubishi Process have been proven on a commercial scale. This paper first gives a brief description of the history of the development work and the characteristic features of the process. The paper then describes the new commercial plant and operating data obtained so far.

Jan 1, 1976

By Michael Cruickshank

All life on Earth relies on the ocean and yet the ocean is 95 percent unexplored, unknown and unseen by human eyes,? said Paula Keener, director of education programs for National Oceanic and Atmospheric Administration?s (NOAA) Office of Ocean Exploration and Research. ?To better understand, manage and protect the ocean and its resources, NOAA believes it is critical to use the best technology to explore, discover, inform, educate and motivate? (MTS, newsletter, January 2011). In the last few decades, our understanding of the global mineral resource base has been drastically changed by some surprising new developments. The potential for commercial minerals per unit area in the oceans and seabed appears to be similar to that of the terrestrial lands. Thus, almost three-fourths of the global mineral resources are in, or under, the sea and are virtually undeveloped. The area of the Pacific seabeds alone is greater than the total area of the global lands. Half of the global seabed minerals are now controlled by nation states within their Exclusive Economic Zones (EEZ). The other half is controlled by the United Nations (UN) through the International Seabed Authority (ISA) within the ?areas beyond national jurisdiction? known as The Area. Thus, the Law of the Sea, ratified in 1994, has resulted in the largest transfer of control of natural resources in the history of mankind. This paper was prepared by the Society for Mining, Metallurgy and Exploration (SME) Committee on the Offshore Technology Conference for the SME Board of Directors and other interested parties. As the premier professional society for the mining and mineral community in the United States, with a history dating back to the 19th century, SME?s mission is to encourage and support young men and women engineers in the minerals industry, provide the services they need, improve the image of the industry, strengthen the networking among global industry professionals and engage in proactive collaboration among industry, government, academia and nongovernmental organizations (NGOs). The accomplishment of this mission can be strongly advanced by highlighting what is probably now the most significant development in the history of the modern minerals industry - the exploration of the marine environment and the understanding of the potential for the development of the minerals therein.

Jan 1, 2011

Powder River Basin (PRB) mines were originally built to serve power plants designed specifically for their coal. Sulfur was the major concern, with BTU and sodium limiting the market for some. The Clean Air Act has extended the PRB market into plants converting from other coals. These new customers are more sensitive to constituents affecting boiler and precipitator performance. At the same time, the prospect of deregulation is forcing power companies to control cost more stringently than ever. Jacobs Ranch Mine has responded to the changing marketplace with an expanded coal quality and customer service program.

Jan 1, 1998

By J. A. Kost

A survey of 80 coal producers was conducted to determine the extent and scope of respirable dust control research for underground coal mines and the current methods employed to control respirable dust. Results of the survey showed that proper face ventilation and an adequate water spray system are sufficient to comply with mandatory standards in room and pillar mining. Difficulties still exist with longwall equipment, auger miners and buring machines. In these cases, known dust control techniques are not sufficient to obtain compliance. Present state-of-the-art face ventilation and water systems were discussed in addition to the sampling program.

Jan 1, 1980

Over the last ten years geological and mining software products have evolved greatly. Software companies developing such products have focussed almost exclusively on the development of technical aspects of the applications, addressing geological, ore reserve estimation and mine planning problems. These specialist applications, and the many other new technologies that are being developed by a myriad of niche developers, are an essential part of todayÆs hi-tech mining operations. Technology is also being used in many other areas to improve the mining process and there is no doubt that tremendous advances are being made in all these fields. Yet there is something missing. The manner in which the technologies are used and implemented has led to the creation of many independent and inefficient æislands of technologyÆ where a variety of products from different vendors are used to address different, but related problems. Problems occur with unreliable information, data duplication, data redundancy and transferring data between applications that may be incompatible or even run on different computer platforms. These problems impede the flow and availability of information and hamper day-to-day decision-making by mine management. A solution to this problem is to take a holistic view of all the various technical applications and incorporate them into a single information technology solution. This solution must encompass all of the information requirements of a mining operation and must provide facilities that address much of the modern thinking about mine management, including strategic mine planning, value management, key performance indicators, and maintenance of a mineral balance sheet. Gemcom is developing an Integrated Resource Asset Management System (IRAMS), which is an enterprise-wide integrated computer system that encompasses various applications typically found at a mining operation. The core component of the system is a common, open, industry standard database that can be shared by many users from each of the different departments at a mine. Around that central repository are the primary applications that provide the mine with information it needs to operate. Ensuring that the information is reliable, accurate, shareable, timely and consistent will eliminate many inefficiencies, and provide significant benefits to mining companies. In turn these benefits will lead to significant improvements in decision-making, productivity and profitability for the operation. The initial version of the IRAMS system is currently being implemented at the De Beers Venetia Mine in South Africa. The system is being built around a core repository using the Microsoft æBack OfficeÆ architecture, and incorporates key technical applications from Gemcom, Whittle, De Beers Technical Team, Wenco and JKTech. The benefits of enterprise-wide systems have long been recognised in the commercial arena and enterprise resource planning (ERP) systems such as SAP, JD Edwards and MIMS are becoming commonplace in the mining industry. The more forward looking software developers and mining companies realise the need for efficient management of the information gathered during the mining process and can see that the concepts used in ERP systems apply equally to the technical applications as they did to commercial applications. The use of IT in the mining industry has expanded tremendously over the last five years as enabling technology and management acceptance has become more prevalent, and there is considerable room for dramatic growth over the next five years. The evolution of geological and mining software has now reached the stage where mines will yield the greatest returns by integrating the applications used in each area of their operations.

Jan 1, 1999

By Takeshita. Takuo

"In this work, the progress of the HDDR process is discussed mainly on the Nd-Fe-B magnet system. There are three technologies being used for the Nd-Fe-B permanent magnet production; the sintering technique, the rapid quenching annealing and the HDDR process. The HDDR process utilizes· the HDDR phenomenon, in which hydrogen absorbing intermetallic compounds go through as they are heated in hydrogen atmosphere, Hydrogenation - Decomposition Desorption - Recombination. In the HDDR process, these four steps in the HDDR phenomenon are processed by choosing suitable reaction conditions regarding to hydrogen gas pressure, temperature, rate ·of desorption and etc., and we can produce permanent magnet powders of good magnetic properties with microstructures consisting with sub-micron size crystalline grains. In the anisotropic magnet powders, the sub-micron size crystals are being mostly aligned in the crystallographic c-axis direction. Possible applications of the HDDR process to other systems are also discussed.Microstructures of the Nd-Fe-B Permanent MagnetsIt is well known that magnet properties of magnetic materials are very sensitive to their microstructures [l]. This is seen in almost all magnet materials from soft magnetic materials and hard magnetic materials to magnetic memory materials. In this regard, the production technology is very important for the control of microstructures of permanent magnets The Nd-Fe-B magnet is the most powerful permanent magnet as a practical permanent magnet, and its coercivity force is much dependant on the microstructure as is the case for other permanent magnets."

Jan 1, 2000

By Y. Ikeda

Typical electric appliances were dismantled into component pieces to study the recyclability of these discarded goods. Types and weight ratios of these component materials were investigated and characterized. The results showed that if they are dismantled properly, these goods could be classified into several groups of similar materials and/or structures, namely those consisting of single materials, metal-plastic combinations, metal-metal combinations and complex combinations of many different materials. By separating each combination into recyclable materials and isolating hazardous materials, it was found that the final waste for disposal could be reduced and the recycling efficiency could be improved markedly as compared to the conventional shredding method. The metal-metal combinations account for 60% by weight of the total metal contents in electric appliances, and therefore, it becomes important to segregate these metals. For the complex combinations, a process consisting of pyrolytic decomposition of plastic contaminants followed by smelting of the residue is proposed. It is anticipated that nearly zero-emission recycling of electric appliances will be achieved by applying this treatment process.

Jan 1, 1995

By L. Yuan, J. H. Rowland, R. A. Thomas, D. Bahrami, G. P. Cole

"The past several decades have seen a steady increase in the use of atmospheric monitoring systems (AMS) in underground mines as sensor technology has advanced and costs for this technology have decreased. The AMS is a reliable tool for early mine fire warning by detecting gaseous products of combustion in underground mines. During a mine fire emergency, mine decision makers rely heavily on the prompt and accurate knowledge of the ventilation and fire situation in the mine, such as fire location, fire size, and the spread of smoke to make effective and efficient decisions on firefighting strategies and miner evacuation. Meanwhile, a prediction of the potential for fire development at a later time, such as whether the currently designated mine escapeways will be contaminated by smoke and toxic gases with the progress of the fire, is critical for effective decision-making to save lives that are in danger. The AMS monitoring data, including carbon monoxide (CO) concentration, airflow rate, smoke, etc., can provide information as to whether the smoke has reached the locations where AMS sensors are installed and if a mine-wide smoke spread has occurred. The National Institute for Occupational Safety and Health (NIOSH) has undertaken a task to integrate real-time AMS monitoring data with the mine fire simulation program, MFIRE, to simulate and predict the spread of smoke and toxic gas in a ventilation network based on the real-time AMS data. This paper reports the developed real-time method for characterizing the size and location of an underground mine fire and for predicting the spread of contaminants throughout the mine ventilation network using sensor data from the AMS.INTRODUCTIONNIOSH conducts research to develop workplace solutions to improve detection of and reduce the risk of hazardous conditions in underground mines. The advancement of senor technology and the increasing demand for real-time mine parameters monitoring have led to extended applications of atmospheric monitoring systems (AMS) in underground mines worldwide. In the United States, AMS is primarily used for early mine fire warning by detecting carbon monoxide (CO) in fire hazard areas, such as belt entries. Mine fires can grow rapidly, and time is the critical element. Prompt detection, timely and accurate warnings to those miners potentially affected, and a proficient response by underground miners can have a tremendous impact on the social and economic consequence of a small underground mine fire (Conti et al., 2005). The early detection of a mine fire could gain time for the first responders to put out the fire before it develops into a disaster. An AMS system with CO sensors has especially played an important role in the early detection of mine fires. The continuous monitoring of an underground mine atmosphere with an AMS could generate a large amount of data in a mine fire event. However, the current application of AMS is mainly limited to sending out an alarm when monitored CO concentration exceeds a certain level. An opportunity arises as to whether these data can be further used in fire emergency response. In order to make effective decisions on firefighting strategies, mine workers’ seeking refuges, evacuation and escape, and the timing on when to send rescuers, decision makers need accurate and timely knowledge of the ventilation and fire situation in the mine. Information about the fire intensity, where in the mine the smoke and toxic gases have spread, and whether designated mine escapeways have been compromised by smoke and toxic gases from the fire would greatly increase the effectiveness of these decisions. However, the monitored AMS data only provides atmospheric conditions in the vicinity of sensor locations. What is concluded from the monitored AMS data highly depends on the decision makers’ capability and experience. Predictive insight into fire growth and smoke transport would greatly help decision makers during a fire emergency."

Jan 1, 2019

By P. K. Jain

A spiral concentrator is a density separation device used for the beneficiation of coal and various minerals such as iron ore, chromite ore, gold, beach sand minerals etc. The flow pattern developed in the equipment is complex and unique, yet the operation is very simple, with low capital and operating expenditure. Spirals are applied for beneficiation of material in the size range finer than 2 mm and are capable of recovering heavy minerals as fine as .01 mm. The understanding of the unique flow pattern has kept researchers engaged over the last few decades and attempts are being made to explain such flow patterns so that they can be controlled and modified to improve the operating efficiency, Ep (Ecart Probable Error, also known as probable error in separation) and acceptability of spiral concentrators for processing of fines and slimes - currently being discarded and dumped in the tailing ponds. An attempt has been made in this paper to explain the generation of complex flow patterns with application to classical solid mechanics in the fluid and slurry system. The same has been used to explain the selective separation of particles in different zones in a cross-section on the spiral trough. The paper also discusses the application of a force balance model to explain the generation of secondary circulation. Due to the presence of laminar and turbulent flow regimes in the spiral concentrator, varieties of equations have been proposed in the literature, consisting of different equations for different zones. An attempt has been made to present a unified flow equation for calculation of flow velocity at different positions on the spiral trough. Keywords: Secondary circulation, spiral concentrator, density separation, fine particle processing

Jan 1, 2020

By D. A. Akinlade, N. L. Richards, D. C. Murray, W. F. Caley

To investigate the effect of adding Ti to a Ni-Cr-Fe powder metallurgy alloy, a thermodynamic software package was used to predict the phase transformations that occurred during thermal processing. Specifically, the effect of adding 3w/o Ti to a 6w/o Al modified ternary Ni-Cr-Fe alloy (the quaternary) was simulated and the phase transformations that might occur in the material on sintering were obtained using the thermodynamic modeling tool. These predictions were subsequently compared with experimental results obtained by X-ray diffraction and metallography. For comparison, selected compacts were prepared containing only the ternary + 3w/o Ti (no Al). Based upon compressibility curves, the optimum pressure for producing the new Ti compacts was 500 MPa vs 600 MPa for the quaternary composition with Ti. In each case, hardness of the base alloy was enhanced by the Ti addition whereas the residual porosity remained relatively constant at about 19%. Finally, although SEM/EDS failed to confirm the presence of Ti in the gamma prime intermetallic, XRD spectra showed a shift in lattice parameter on addition of Ti, suggesting that the intermetallic was of the form Ni3(Al,Ti).

Jan 1, 2010

By W. J. Kroll

This investigation was undertaken with the idea of studying a number of unconventional methods for making chromium to determine whether production cost could be lowered and to discuss some of the more recently described processes. These comprise carbon reduction of the oxide in vacuum, nitride dissociation, fusion electrolysis of the chloride, amalgam method, iodide dissociation, calcium reduction of the oxide, hydrogen reduction of the chloride, and reduction of this compound with zinc and with magnesium. Preference is given this latter method, which is shown in a flow sheet. Special attention is given purification of the chloride and separation of the vacuum at about 900° C. A reduction method for the elimination of traces of oxide contained in pure chromium by pure hydrogen obtained from the dissociation of zirconium hydride is described. The various methods are compared in a table in the appendix. Aluminothermic and silicothermic methods for the reduction of chromium oxide and the aqueous electrolysis have been disregarded in this investigation.

Jan 1, 1950

By Orlando C. Gaspar

Abstract - The presence of fine-grained mineral intergrowths, the complex distribution of deleterious minor elements, and the variable base-metal contents in some assemblages commonly pose technical problems for the processing of volcanogenic massive sulfide ores. The beneficiation of most massive sulfide ores from the Iberian Pyrite Belt requires extremely fine grinding to liberation sizes of K80 = 15 µm to 25 µm. For several deposits, mapping of the ore types and metal zoning patterns has shown that the different ore types are distributed as ore lenses within the massive sulfides. Mineralogical, textural, and metallogenetic studies have provided an understanding of the distribution of both the vertical and the horizontal metal zonation in the orebodies. Because the efficiency of ore processing is affected by ore textures, and because the same mineral commonly has different textures and varies in chemical composition, a relationship between textures of the feed and the middlings must be established for all ore types defined at the deposit scale. Quantitative mineralogical methods have been developed to provide, on a timely basis, the information needed to optimize the concentration processes for the massive sulfide ores at the Aljustrel and Neves-Corvo deposits, Iberian Pyrite Belt, Portugal.

Jan 1, 1997

By Liliana Rybarska-Rusinek, Aleksandr M. Linkov, Ewa Rejwer-Kosińska

Joined modeling of stressed state and induced seismicity is a means to join geomechanics with seismic observations. When applied to quantifying rockburst hazard, it provides, on one hand, estimations in terms of mechanics, such as stress concentration, and, on the other hand, in statistical terms of the risk analysis developed in mining seismology. The modeling became possible due to progress in computers and numerical methods. However, despite tremendous increase of computational abilities, the joined modeling is still quite time expensive. To make it available for wide use and real time simulations, there is need to reduce the time cost of its key stages: calculation of stresses, caused by mining, and simulation of seismic events, induced by these stresses. The present work aims to decrease the time cost. The stages are time costly because of the same reason, which is a very large number N (up to millions) of elements, representing rock structure, openings and flaws. This leads to immense computational complexity (roughly of order N2) of conventional accounting for pairwise interactions between the elements. The complexity may be notably reduced, when employing the fact that interactions decrease with growing distance between elements. Specifically, the fast multipole methods (FMM) avoid the complexity N2, by employing translations of far-fields from whole collections of sources. This reduces the complexity to the order 22, where p is the number of terms involved in a single translation, is the number of translations, and is the dimension of the quantity translated. Still, for conventional FMM, the complexity remains too high to routinely perform joined modeling of stresses and seismicity.

Apr 26, 2022

By E J. Hill, F Huang, A Otto

Geochemical data from drill core samples is used in mineral exploration to enable geologists to understand subsurface geology. However, it is challenging to analyse these data sets rigorously and consistently. Manual data interpretation relies on the knowledge and experience of logging geologists. When multiple geologists are involved, it is possible to introduce inconsistencies in logged lithology type and scale of logging (‘splitters’ versus ‘lumpers’). Machine learning (ML) is a powerful tool for analysing high dimensional data (ie data with many variables) and large data sets (ie data with many samples). However, ML methods applied to drill hole samples do not incorporate spatial information and this can result in high misclassification rates and small-scale ‘noisy’ results. We demonstrate the use of multiscale spatial analysis (wavelet tessellation) as a pre-ML step to analyse spatial information. This step helps reduce misclassification and filter out unwanted small-scale variation in the data. In an experiment, we used wavelet tessellation and supervised ML to predict litho-geochemical rock types from geochemistry data. The data set is from the Valhalla uranium deposit near Mount Isa, northern Queensland. First, geochemical knowledge and statistical analysis was used to select appropriate geochemical elements for litho-geochemical classification. Second, the elements were processed using multiscale spatial analysis. Third, we trained a Random Forest model with the data set and found that the model performs worse in predicting rare rock samples than common ones. We applied over-sampling and down-sampling methods in aim to overcome this issue. As a conclusion, the combination of multiscale spatial analysis (to define rock unit boundaries) and Random Forests (to classify rock units) is a good method for rapid and accurate analysis of drill hole geochemistry.

Mar 22, 2022

By D. H. Rubisov

The neural networks modelling approach is one of the most elegant black-box type methods to model industrial processes. In this paper, this approach is applied to model the performance of the CEZ zinc electrowinning plant. The model that was built was found to exhibit an excellent predictive ability for voltage and current density. The model was also used to investigate the sensitivity of the process to various key variables such as temperature, current density, zinc and sulphuric acid concentration, etc. Optimal regimes for zinc production were identified from the power consumption standpoint.

Jan 1, 1996

By R. R. Sayers

A series of coal- mine catastrophes in the latter part of the first decade of this century focused public attention on the need for safety in mines and resulted in the establishment of the Federal Bureau of Mines , whose primary function was to promote safety and improve hygienic conditions of workers in the mineral and related industries . These activities are carried out by the Safety Division of the Bureau's Health and Safety Service . In general , the work performed by the Safety Division personnel may be classified as educational and investigative . Instruction is given in accident prevention for mine officials and miners ; first aid to the injured ; the use and care of oxygen breathing apparatus ; and advanced mine rescue and recovery operations . A specialized safety course is offered to the petroleum and gas industries . Division personnel also aids in or directs rescue and recovery work after mine fires and explosions ; assists at first - aid and mine rescue contests ; conducts safety exhibits and demonstrations ; and presents safety talks , often accompanied by sound safety motion pictures or latern slides , before employee and official groups , at meetings of Holmes safety chapters , at mining institutes , and at other safety or technical gatherings . Coal - mine fires and explosions are investigated , as well as quarry or metalmine explosions and fires , miscellaneous accidents , health and safety hazards , and safety conditions at mines and plants ; safety devices are investigated and developed . Field studies cover ventilation , methods of allaying suspended coal - dust particles , prevention of dust accumulations , the proper use of rock dust to prevent or limit explosions , explosives practices , and the care and use of underground equipment . The results of these studies and investigations are widely applied in the various training courses and are prepared as reports and recommendations , which are submitted to interested persons or are combined and distributed to the public as bulletins , technical papers , miners ' circulars , information circulars , and reports of investigations . These studies also afford a basis for the development of new or modification of old Safety Decisions of the Mine Safety Board of the Bureau of Mines . The following pages review the accomplishments of the division as regards safety during 1942,2/ with like information for a series of recent years and summaries to date . A striking feature of the division's work has been the safety education of more than 1-1/2 million persons who have taken first -aid and mine rescue training courses . That these efforts over a period of 3 decades have been successful is revealed by the decline in coal - mine fatality rates and a somewhat smaller decrease in metal - mining and quarrying fatality rates .

Apr 1, 1943

By A. Pareek, V. S. Masampally, V. Runkana

Mineral processing plants, in general, consist of comminution and separation circuits. Rougher flotation is considered as the heart of the separation circuit with concentrate grade and mineral recovery being the key productivity and quality parameters that affect the downstream operations and profitability. Online prediction of these parameters can help improve process performance in real-time. Past efforts to predict flotation cell performance have focused on building physics-based or machinelearning (ML) based models. Although physics-based models are popular in process design applications, ML models are more appropriate for online monitoring, control and optimisation due to their lower computational requirements. Deep learning (DL) is gaining prominence nowadays for application in industrial operations where a large amount of data is available. We have developed a DL model based on long short-term memory (LSTM) neural networks to forecast the two key performance indicators (KPIs), namely, mineral recovery and concentrate grade in a mineral processing plant. Rougher feed characteristics such as mineral grade and particle size distribution, upstream measurable disturbances such as throughput of the comminution circuit and pulp density, and control variables such as aeration rate, pH, and collector addition rate are considered as explanatory variables to train the model. The model was tested with data from an industrial mineral processing plant. For real-time dynamic predictions, the trained model appropriately accounts for mismatch in measurement frequency of real-time process data and off-line laboratory analysis data. Such a time series model can be used as a state observer in model predictive control techniques for optimal control of unit operations in a mineral processing plant. Keywords: Mineral processing, flotation, time-series, dynamic modelling, deep learning

Jan 1, 2020

By W. H. Langer

Around the beginning of the 20th Century, annual aggregate production in the United States amounted to about 50 million short tons. Today annual aggregate production is nearly 2.5 billion tons. Over a third of the States in the country produce more aggregate than the Nation did at the turn of the century. I would like to describe some of the historical events that allowed this nearly 50 fold increase in aggregate production. You might wonder why I want to talk about history. Some of our best ideas lie buried in the past, waiting to be rediscovered in the present. Almost every issue that the aggregate industry experiences today has been recognized for at least a decade; many of those issues have been recognized for a half a century; and a few of them have been recognized for nearly a century. The main reason for this article is to save the past from the forgetful indifference of the present-to faithfully preserve the past, to illustrate the insights of our predecessors, and to demonstrate how little of what we know today is really new.

Jan 1, 1998