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By Ann Bigué

Outline of Presentation 1. Impacts and Benefits Agreements Defined 2. Elements that determine the content of an IBA: ? the nature of the project ? the identity of Aboriginal communities affected by the project ? the legal environment 3. Content of Impacts and Benefits Agreements Impacts and Benefits Agreements Defined Have emerged in response to effects of major mining projects located on or close to Aboriginal lands and close to Aboriginal communities Are negotiated between the mining project proponent and one or more Aboriginal groups May include government May be known under other names

May 1, 2004

By François Charette

High stress conditions in weak rock masses lead to large deformation and breakdown of the rock material, while stress release events in hard rock mines can lead to sudden and usually violent rock failure. Typical support systems combine various reinforcement and support mechanisms to provide the required convergence control and retainment, but results are often mitigated by failure of surface liners, shotcrete and tendons. The paper reviews differing requirements of support and reinforcement for different failure types. In addition, the mechanical performance of a new reinforcing tendon is presented and analysed in view of the field requirements. Field tests results are presented.

May 1, 2011

By K. D. Card, K. Howard Poulsen

Abstract - The Archean Superior Province craton and the Paleoproterozoic Penokean Orogen are major geological sub-divisions of the southern Canadian Shield and account for much of the metallic mineral production of North America. The Superior Province experienced a mainly Archean history involving several cycles of volcanism, plutonism, and tectonism, primarily in the Neo-archean but also including Meso-archean and Paleo-archean cycles as well. Superior Province consists of northern and southern high-grade gneiss sub-provinces and a broad central region of alternating greenstone-granite and metasedimentary belts. The sub-provinces may represent tectonic terranes assembled in the Archean by accretion processes similar to those of some Phanerozoic orogens. Most of the mineral deposits, including VMS, intrusion-related, and lode gold deposits occur in the greenstone- granite sub-provinces where they were formed in an interval of 100 million years or less around 2.7 Ga. The Paleoproterozoic Penokean Orogen comprises supracrustal sequences deposited in fault-controlled epicratonic and rifted margin settings developed on and about the Superior craton. Deposition of the ~2.4 Ga Huronian Supergroup and its paleoplacer uranium deposits in the eastern Penokean Orogen, and their pre-2.2 Ga deformation, were probably unrelated to the deposition of the ~2.1 Ga Marquette Range and Animikie groups and their major taconite iron formations in the west. However, these sequences were deformed together during the ~1.85 Ga Penokean Orogeny which resulted when an assembly of island arcs containing VMS deposits, the Wisconsin magmatic terrane, collided with the Superior block and its Paleoproterozoic cover. The Sudbury structure with its world class Ni-Cu-PGE ores was also formed at this time, possibly triggered by meteorite impact. Metallogenic patterns in the Paleoproterozoic rocks were controlled by a complex interplay of factors including tectonically controlled variations in deposition and deformation, distribution of mineralization in the Archean basement, and oxyatmoversion, the transition from anoxic to oxygenic atmospheric conditions that occurred during the deposition of these sequences.

Jan 1, 1998

By Mark W. Bartlett

Program Objectives ??Identify and implement a tool for haul truck drivers that: -Reduces or eliminates fatigue-related injuries and fatalities -Reduces accidents and equipment damage ??Following evaluation period, apply tool where most effective Why do We Need a Fatigue Monitoring Tool? ??Everyone has probably fallen asleep while driving ??Driver fatigue is a major source of property damage and serious haul truck serious incidents ??To protect ourselves from the other ?tired?driver ??To know when to ask for relief ??To know when we are seriously distracted from driving ??To measure improvements in sleep incidents based on shift changes and intervention ??To help prevent incidents like the following:

May 1, 2011

By M. N. Pons, E. Benizri, B. Laubie, A. Bani, Université de Lorraine LRGP, P. Kidd, A. J. M. Baker

"Serpentine (i.e. ultramafic) outcrops in Europe cover more than 10,000 km2 and have a low-fertility and low-productivity, making them unattractive for traditional agriculture. In general, these areas are slowly abandoned by local farmers, affected by strong rural exodus and landscapes undergo a process of closure. However, ultramafic landscapes have the potential to provide multiple ecosystem services that can contribute to Europe’s goals towards insuring food security, production of renewable raw materials and renewable energy. Phytomining (agromining) aims at cultivating metal hyperaccumulator plants that are able to accumulate Ni and other strategic elements from metal-rich soils and transport them to the shoots (>1%), which can then be harvested as a bio-ore. Such metal-rich biomass can be used to recover highly valuable metals, e.g. nickel (Ni) and also to produce energy (heat, electricity). Nickel agromining can thus offer an eco-efficient alternative to classical pyro- or hydrometallurgical processes without disturbing the soil cover and the geology from soils and rocks that would be considered as low grade ores or sterile material for conventional mining methods.Phytomining agroecosystems can lead to better soil resource efficiency and can offer a fully integrated, new agromining agriculture that could cover thousands of km2 in Europe, benefit local communities with a sustainable rural development and provide a wide array of ecosystem services which will need to be optimised under a life cycle assessment methodology:1. Production of bio-sourced metal products2. Production of energy biomass3. Restoration of soil fertility for conventional agriculture (Ni stress)4. Limiting Ni intake by local populations and farmers5. Use and conservation of local biodiversity (plant and soil fauna and microflora) as cultivated ecosystems6. Store carbon in cultivated soils7. Enhance pollination activity at landscape level.Nickel agromining could therefore change the economical balance in historically-disadvantaged ultramaficregions of Europe"

Jan 1, 2016

By J. G. Schofield, C. G. Tan, R. J. Ord

"Most electric furnaces in the nickel and copper smelting industries are still fitted with conventional electrode holders which consist of water-cooled electrical contact clamps and a pressure ring. The water cooling exerts a significant cooling effect on the electrode column. The importance of controlling the temperature of the Soderberg electrode paste at the contact clamp area is examined, using in-plant experience and computer simulation of the paste melting and baking process. In addition to the effect of water-cooling, the effect of other variables, including the mantle air temperature, the electrode current, the furnace freeboard temperature and the electrode slipping rate are discussed. Ways in which the variable heating conditions in the paste melting zone can be controlled are outlined.IntroductionIn most non-ferrous electric smelting operations, the breakage of Soderberg electrodes is an infrequent, isolated occurrence. Occasionally, however, a rash of breakages may be experienced on a particular furnace for what appears to be no obvious reasons. The extent of the breaks may not exhibit a uniform pattern; sometimes the break may be less than half a metre above the electrode tip; at other times it may be at or just below the roof level. The latter type of break is, of course, the most dangerous since it is closest to the non-baked, weak portion of the electrode paste column. No matter where the breaks occur, they result in abnormal furnace power, charging and tapping conditions and loss of production while the new electrode section is slipped and baked. On a six-electrode furnace, breakage on one electrode has the immediate effect of reducing the total furnace power by one-third. On a three-electrode furnace, the effect is more drastic, one half of the power being lost."

Jan 1, 1995

By M. Gauthier, A. C. Brown

"Monometallic zinc mineralization associated with marbles of the Grenville Supergroup in the Mont-Laurier Basin of Quebec is found to be stratiform and to occur (1) within limited zones of dolomitic marble and (2) more precisely along contacts between these marbles and adjacent metaclastic units. Massive sphalerite with accompanying pyrrhotite and pyrite is the prime exploration target, and commonly gives rise to good geochemical anomalies, but generally weak and ambiguous geophysical responses. Disseminated sphalerite in dolomitic marbles may signal proximity to interesting massive mineralization, although, due to weathering, this broadly disseminated mineralization may not be detected easily on outcrops. It is concluded that the western and possibly the eastern margin of the Mont-Laurier Basin constitute favourable areas for continued exploration.IntroductionThe Grenville Supergroup marbles of Ontario, Quebec and New York State host numerous occurrences of zinc mineralization (Fig. I) , several of which have been periodically mined since the beginning of this century (Fig. 2). The Balmat Edwards district of New York is the giant of this depo sit-type, with the production since 1915 of some 20 million tons of ore grading 10% zinc, and acknowledged current reserves of approximately equal tonnage and grade. At present, there is renewed interest in the potential for similar mineralization throughout the Grenville Supergroup, and this paper outlines some of the geological, geochemical and geophysical guidelines that may be employed in the search for new ore. The geologic guidelines are derived especially from lithologic and stratigraphic features which survived intense, multiphase deformation and metamorphism.Although major portions of the extensive Grenville Supergroup hold potential for zinc mineralization, the present study is confined to a known zone of mineralization in the Mont-Laurier Basin of Quebec. Concurrently, we are compiling information on the regional metallogeny of the basin so that our conclusions can be applied to areas of similar Grenville Supergroup host-rocks elsewhere."

Jan 1, 1980

By D. Bouchard, J. Langlais, A. Lemieux, N. Andrade

A concerted effort between Akan International Limited and the National Research Council of Canada (NRC) has been initiated to develop a liquid-based slurrymaking process, dubbed SEED (Swirled Enthalpy Equilibration Device) for semi-solid forming. The technology is presently entering the industrial and commercial stages, and will be used by the first customers at the end of 2006. Semi-solid processing of aluminium alloys offers many advantages in fabricating economically near-net-shape parts of superior quality. The SEED process helps to overcome problems experienced with thixocasting and especially the high cost of feedstock. The SEED process involves two main steps: 1) heat extraction to achieve a desired liquid/solid mixture, and 2) drainage of an excess liquid to produce a self-supporting semi-solid slug that is formed under pressure. The heat transfer plays an important role (enthalpy equilibrium) during the manufacture of the semi-solid slurry and its analysis is briefly described. The semisolid material is obtained using different processing times and initial conditions. The impact on the solid fraction distribution and the morphological evolution of the microstructure is presented. The influence of the SEED processing parameters (slurry preparation) and the resulting mechanical properties for the alloy A356 are also reported.

Jan 1, 2006

By Pascal Lesagel

Life Cycle Assessment (LCA) is a holistic environmental assessment tool that allows the compilation and evaluation of the inputs, outputs, and potential environmental impacts of a product or service throughout its life cycle, from cradle to grave (i.e., from resource extraction and transformation to final disposal, including production and use stages). The relevance of LCA for the mining industry is twofold. First, the mining industry has a role in providing the LCA community the data that allows subsequent evaluations of the life cycle environmental impacts of primary materials such as metals, as well as the environmental comparison of the downstream products of the mining industry with other competing materials for specific uses. Second, the mining industry can use LCA in order to evaluate the environmental impacts of its activities, identify their environmental hotspots and compare the impacts of available technical options. For example, the environmental impacts of different extractive and processing technology can be compared through the use of LCA. This latter use of LCA by the mining industry is less common. This paper discusses the use of LCA to compare sulphidic tailings management options. The paper also presents some of the LCA research challenges that still have to be addressed to increase the relevance of LCA results for the specific context of mining activities.

Nov 1, 2008

By K. Kawagishi, K. Matsumoto, Y Koizumi, H. Harada

A new burner rig for cyclic and hot corrosion testing of Ni-base superalloys and high-temperature coatings has been developed at the National Institute for Materials Science (NIMS) in Japan. The concepts of the rig design include: use of kerosene as fuel, easy operation for materials research and multi-specimen testing capability per test run. The burner rig consists of six blocks including combustion block, corrosion-solution injection block, furnace block, specimen block, controller block and outdoor facility block. During verification testing, it was confirmed that the rig had accurate specimen temperature control within ±1? from 600 to 1100? and automated easy operation. Cyclic testing of several Ni-base superalloys was conducted. The results from 50 cycle testing indicated that a new NIMS alloy developed for 1700? class gas turbine had higher oxidation resistance than CMSX-4. This new burner rig testing capability at NIMS can be very useful for future oxidation, hot corrosion and coating durability studies.

Jan 1, 2010

?It is not the strongest of the species that survives, nor the most intelligent. It is the one that is most adaptable to change.? Charles Darwin. Canada?s mining and exploration companies have evolved over the past century from essentially a pick-and-shovel industry to a high-tech industrial sector. This evolution has occurred in fits and starts, and has been driven by the shifting environment of economic, technical and social opportunities and pressures in Canada. As labour costs have gone up, and labour availability has gone down, the industry has evolved more efficient processes. As mineral prices have increased or fallen, the industry has evolved either by expanding or shrinking production, or by changing processes to adapt to the newly prevailing conditions. As stringent environmental protection legislation has been implemented, the industry has adapted accordingly, and has substantially changed its mindset to incorporate sustainability into its way of doing business. These changes have occurred over a number of decades, and have usually occurred as the industry?s reluctant response to pressures it couldn?t evade. This model mirrors the classical paradigm of natural selection where evolution is driven by pressures external to the organism (or organization) ? change occurs to the degree necessary for survival and prosperity, but generally no further. In recent years a new paradigm has started to come into play in Canadian mining and exploration. Rather than only a reactive response to the external economic, social and technical factors, groups within the mining community are becoming proactive in developing strategies for future adaptive change. Instead of each against the other, they are developing more sophisticated paradigms where they can both compete against (such as in marketing) and cooperate with (such as for tech development) their fellow organizations. Most importantly, they are seeing individual and national advantage in a collaborative Canadian approach to address the advantages of overseas competitors who often have lower labour costs, lesser environmental standards, or more accessible markets and transportation. This has translated into large-scale mining community support for the Canada Mining Innovation Council, and its programs in exploration, mining, processing, HR development, energy and environmental stewardship. This new paradigm is adaptive to the current environment but is substantially different from the older way of doing business in two major ways ? it is based on a collaborative approach to competitive advantage, and it is highly proactive rather than reactive. All the programs have their priorities determined principally by the mining and exploration companies, whose first obligation is to determine the long-term research priorities of the industry as a whole, rather than for their individual companies. Only after industry consensus on priorities does the research community become engaged in the implementation of specific projects to address those identified priorities. A goal of the program is to effectively create a virtual mining research laboratory, by engaging all the major research centres in the country. This approach is being actively adopted by much of the Canadian mining community, and argues well for the adaptability and long-term survival of mining in Canada.

Aug 1, 2013

By A. J. Rigby

The wear mechanisms of the tuyere lines of Peirce-Smith and Hoboken converters are a subject of endless debate and speculation. However, there has been an indication that one of the primary factors in the deterioration of tuyere lines is due to the batch operation of the converting process. The cooling of the brick in the tuyere line during out-of-stack times leads to shrinkage of the brick and resultant opening of the joints. Subsequently, on re-entry of the tuyere line into the bath, the joints become penetrated with matte and re- expansion of the brick is prevented. It is thought that this regular cycle of exiting the batch for slag skimming and replenishment of matte and re-entering for further blowing leads to a gradual “ratcheting” of the tuyere brick lining. If no expansion allowance is furnished between the endplate and the endwall of the lining, then the generation of damaging compressive stress is unavoidable. INTRODUCTION It is generally accepted industry-wide that the integrity of a refractory lined vessel is determined by an inextricable combination of refractory brick quality, the caliber of the lining design and installation, and the severity of the process inflicted upon the high wear areas of the vessel lining. Rigby has summarized the concentrated attempt, over the past several years, to optimize the microstructural, chemical, and fracture properties of the refractories used in non-ferrous pyrometallurgical vessels. Furthermore, lining design concepts involving larger and longer brick and the extent and positioning of expansion allowance in the joints have been extensively trialed. All these efforts have provided some, but not startling, improvements. The simple fact is that a vessel lining composed of bricks with an optimized microstructure and chemical inertness must installed with a well-conceived design to decompress the lining stresses that are generated by the batch operation of copper converters. REFRACTORY QUALITY Converting is conducted by injecting air into the molten matte and white metal for the very purpose of generating iron and copper oxide slags. These slags must be contained by a refractory which, by its mineralogical formulation, is optimized for chemical inertness.

Jan 1, 2019

By G. Issid, J. McGinty, C. Lee, Y. Pepin

For more than a decade, Hatch has used process and logistics models to assist Rio Tinto Fer et Titane (RTFT) with capacity planning, debottlenecking, and optimization to help ensure design capability, capital effectiveness, and operational efficiency of the integrated production chain. Process models are used to optimize the physics-based aspects of the system, such as mass and energy balances, flow rates, yields, and equipment specifications. Dynamic logistics models are used to optimize how the various plant areas work together to achieve the desired ends and deal with such things as plant scheduling and synchronization strategies, sizing of buffers between processes, defining the required number of process and material handling units, and designing a plant layout that minimizes plant interferences and inefficiencies. The combined use of process models and logistics models enables the overall plant to be optimized from both a productivity and quality point of view, with each plant area working in harmony with one another to achieve targeted capacities and efficiencies. This paper describes the many benefits derived from such modeling efforts over the past 15 years for each of the major plant areas at RTFT: Beneficiation Plant, Smelter Plant, Steel Plant, UGS Plant, and Powder Plant (RTMP).

Jan 1, 2011

By S. Litke

Elemental sulfur was stockpiled at the Mount Polley Mine for use as a source of sulfuric acid as part of research into leaching copper from oxide ores, but the project did not proceed beyond an initial pilot- scale evaluation. Since placement, the sulfur has oxidized and some sulfuric acid leached into the underlying rock. The reaction of the acid with these underlying materials has been studied as part of an evaluation of the effects of leachate from the pile. The rock underneath the sulfur pile is composed dominantly of primary and secondary alumino-silicates with less than 1% carbonate (calcite) and iron sulfide (pyrite). In its unaltered condition, the rock is classified as non-acid generating. Conceptually, it was expected the sulfuric acid would be neutralized by the rock to varying degrees resulting in a series of pH-controlled weathering fronts progressing from leached near the contact with the sulfur pile (pH <3), to active neutralization by silicates (pH 4–5), to active neutralization by carbonates (pH >7). The rocks underneath the pile were sampled to determine the extent to which the rocks had reacted and their long-term stability after removal of the acid source. INTRODUCTION When rock is blasted and excavated to facilitate mining ore, it is typically placed and stored on the surface in piles. The resulting drainage may have a neutral to basic pH (i.e., non-acidic drainage) or a low pH (i.e., acid rock drainage, ARD) depending on the mineralogy of the rock being stored in the piles. Acid- base accounting (ABA) can be used to characterise the two types of rock: potentially acidic drainage generating (PAG) and not potentially acidic drainage generating (NAG) (Price, 2009). According to Price (2009), NAG is defined as having an excess of neutralization potential (NP) in the rock in the form of calcium carbonate-like minerals when compared to acid potential (AP), i.e., a Neutralization Potential Ratio (NP/AP = NPR) greater than 2.0, whereas PAG is classified as having an excess of AP (i.e., an NPR less than 1.0). This is a conservative estimate and may be slightly modified depending on the mineralogy at specific mine sites. Rock with an NPR of 1–2 is also capable of generating acid (Price, 2009) and, depending on the mineralogy, may also be classified as PAG. Drainage from PAG material can generate acid immediately, or many years after it has been exposed to surface conditions. Disposal techniques depend on the category (i.e., NAG or PAG) and reactivity of the rock stored in the piles.

Jan 1, 2019

By J. D. Galloway

The mining industry of British Columbia continues to grow steadily in importance. The gross value of the production in 1925, sixty-two and a half million dollars, was a record, and ali indications point to the 1926 output registering a still higher figure. In an industry such as mining, where production means the depletion of known ore reserves, the discovery and development of new &apos;ore-deposits is of the utmost importance. To maintain and increase production, steady development is essential. In this respect, the record of the last three years in British Columbia mining is most satisfactory, as in this period more real development has been carried on than in any similar period in the history of mining in the Province. Prospecting, or the search for new ore-bodies, has also been fairly active, but comparatively few important new discoveries have been reported in the past few years. The mineral output of British Columbia consists of Iode minerals, coat and coke, and building materials. In 1925 the value of the output of these three classes of products was, respectively, about 46, 13, and 3 million dollars. The industry as a whole embraces the mining of these materials, and the treatment and manufacturing processes involved in preparing the various products for the market.

Jan 1, 1926

By W. van der Merwe

With the gold industry looking to process more complex ores, the online measurement and control of cyanide addition to the gold leaching circuit has become more crucial. This paper compares the two commonly employed "free" cyanide online analysis methods (amperometric and potentiometric end-point silver nitrate titration) with the common site laboratory rhodanine endpoint silver nitrate titration and ion selective electrode methods. Measurement differences between these methods are presented and discussed for cyanide solutions containing copper and zinc with varying cyanide to metal ion ratios. The resulting cyanide available to leach gold is also compared with these measurements.

Jan 1, 2011

By W. Gordon Muir

This paper deals with the exploration, development and current operations of the salt mine at Goderich, Ontario operated by the Sifto Salt Division of Domtar Chemical Limited. The rock salt is obtained from a bed 1,760 feet below the surface, 75 feet thick, extending under Lake Huron. Annual production is in excess of one million tons. Large mobile equipment is used. Details of this equipment, as well as the shaft layout, which permits the equipment to be lowered underground with a minimum of trouble are outlined. Mining, crushing and screening procedures' are rev1ewed. Reference is also made to productivity salt distribution and uses.

Jan 1, 1967

By André Bérubé

Since the disappearance of Les Forges du Saint-Maurice at the end of the last century, many historians have taken an interest in the lengthy past of this enterprise. They considered the political, socio-economic, administrative and anecdotal aspects of the industry, but barely dealt with the elements of technology. The purpose of this article is to try to fill this gap (1). Les Forges du Saint-Maurice was an integrated industrial concern, specializing in the production of semi-finished wrought iron and finished cast iron that operated almost without interruption between 1734 and 1883. Les Forges first came into being in 1729, when Montreal merchant Franc;ois Poulin de Francheville submitted to the King of France a request for the right to exploit the bog iron ore deposits on his seigneury of Saint-Maurice. This request, agreed to in 1730, was one of a long series of attempts, previously unsuccessful, to establish a local iron industry in the colony. Several such proposals were held up by a lack of capital from promoters or a too rigid application of the mercantilist policy by the metropolis. In 1730, however, the French minister Maurepas favoured a more liberal policy which would encourage private enterprise. The benefits of an iron industry to the naval construction industry was a factor that caught the attention of administrators. The choice of the site for Les Forges was based on the following factors: - the abundance of surface deposits of bog iron ore in the Saint-Maurice region; - the presence of a vast supply of hardwood and conifers needed in large quantities by this industry; - the proximity of sandstone and limestone deposits, md1spensable materials for the construction and operation of the blast furnace; - the presence of a water stream, with sufficient flow to provide the hydraulic power needed for the operation of the machinery.

Jan 1, 1999

By A. Roca, V. A. Quezada, O. A. Benavente, M. Cruells

The leaching pretreatment of copper ores is widely used in the Chilean mining industry. Agglomeration and acid curing have been identified as the most useful pretreatments. Of these, acid curing was recognized as beneficial in the dissolution of copper minerals, even in sulphides such as chalcopyrite. Extensive acid curing times have an impact on copper extraction, generate a homogeneous acid distribution in the mineral bed and benefit the inhibition of aluminum-silicate minerals (acid consumers). This document describes some of the theoretical background and results regarding the effect of acid curing in a chalcopyrite sample with 74% purity according to Qemscan analysis and a 28.5% of total copper. Leaching tests are carried out at 25, 50 and 70°C, evaluating the effect of a pretreatment on the chalcopyrite dissolution. The original sample and products generated were characterized by X-ray diffraction analysis and Scanning Electron Microscopy (SEM). The performed experiments indicate a direct relation between the effect of curing time and temperature in copper extraction. 92% of copper can be extracted in a leaching at 70°C and with 15 days of curing. Elemental sulfur, jarosite and copper polysulfide (CuS2) have been detected in leaching products. INTRODUCTION The copper extraction from minerals is a technique that has been developed for hundreds of years in the world. In 2017, the largest copper producer was Chile, exported 5.5 million tons (COCHILCO, 2018). However, in order to preserve this production level means overcoming multiple challenges. In the case of the Chilean copper deposits, the average copper grade in 2016 was 0.65%, lower than the 1% declared in 2004 (Consejo Minero, 2018). This is mainly due to the deeper of the deposits reaching sulfide mineral zones, mainly chalcopyrite. Traditionally, these sulfurized zones ore are treated through concentration by flotation and subsequent pyrometallurgical treatments. However, for some copper companies it is complex to process by this alternative, due to the high costs and high rates of water consumption. The mineral resources of these companies are known as "low-grade sulfides" and do not allow, economically, the treatment of these minerals through concentration by flotation. This is how hydrometallurgy becomes an alternative for the treatment of this type of deposits. In addition, several companies have hydrometallurgical plants, which would allow the operational continuity of these plants.

Jan 1, 2019

By J. Ander

About fifteen years age some mines in western Canada commenced using Diesel engines, partly for development work but also for operations on quite a large scale. In the Eastern mining field, the Diesel engine made its appearance some eight years ago and has since, at quite a number of mining plants, proved to be a reliable and economical prime mover. As a result, it is today used more extensively than could have been foreseen only a few years ago, and it is reasonably safe to predict that the next few years will see the Diesel engine utilized to a still greater extent in the Canadian mining industry. It is not much more than thirty years since the first Diesel engine was put in operation. During the early years of this century, the Diesel engine took, so to say, its first faltering steps in public service. Since then it has reached a high state of perfection, and its importance has grown in a most remarkable way, until today it is used in practically every field where power is required. It is slowly but surely superceding steam for a great many purposes, as, for instance, for ship propulsion. While in 1921 only about 8 per cent of all tonnage launched was motor-driven, the proportion had grown to 38 per cent in 1927, and for 1929 it was slightly over 45 per cent. Some of the finest passenger liners afloat are Diesel-driven. In the early days, Diesel engines were built only in comparatively small units. Today engines with a capacity per unit of up to 10,000 horsepower, or even more, are being built for marine and stationary purposes.

Jan 1, 1930