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By Shawn Healey, Ray Norcross

"Site IdentificationNew Britannia MineA 50/50 WX Gold Inc. - High River Gold Mines Ltd. Joint VentureTVX Gold Inc. is the OperatorLocationThe New Britannia Mine is located in the town of Snow Lake, Manitoba, which is situated between Flin Flon and Thompson, 420 miles north of Winnipeg.Brief Description of OperationNew Britannia Mine processes 2000 tonnes per day at an average grade of 4.5 g/t. Mill recoveries are currently 91 YO, accounting for forecast of 98,000 ounces for 1998.New Britannia Mine's mill complex incorporates conventional crushing, grinding and carbon-in-pulp technology. The design capacity of the New Britannia Mine mill is 1850 tonnes per day. The mill has processed upwards of 2300 tonnes per day, with no required upgrades.Gold recovery averaged 89.8% for 1997 compared to the planned 87% recovery expected from projected metallurgical test work. Year to date recovery mid December 1998 stands at 91.1 %Cash costs for the 1998 year to date were down to U.S. $221.49 per ounce, down 12% from the 3rd quarter of 1997. Milling costs for 1998 YTD were at Cdn. $9.38 per tonne and Cdn. $73.50 per ounce.Geology - (Orebody Description)The Snow Lake gold deposit is located within the Aphebian Flin Flon / Snow Lake Greenstone belt. This belt is composed of an assemblage of poly-deformed volcanosedimentary supercrustal sequences intruded by pre and sin tectonic ultra mafic and mafic intrusions and sin to post tectonic granitoid.The principal gold bearing rock at the New Britannia Mine is made up of quartzcarbonate material in sequence of basic and acidic volcanic rocks contained within a shear zone. The ore itself is gold associated with the sulphide mineral arsenopyrite and contains some pyrite, pyrotite, plus chalcopyrite. Proven and probable reserves at December 31, 1997 were at 4.04 million tonnes at 4.6 g/t and underground exploration continues to confirm the extension of the ore zones to depth."

Jan 1, 1999

"An innovative concept is proposed whereby the operating power for haul trucks in certain areas of an underground mine are reduced in order to lower ventilation costs. Airflow that must be provided for diesel-powered equipment in most jurisdictions are regulated based on engine peak power capability and engine emissions, both of which can be lowered by artificially reducing the capacity of the engine through the engine control unit. Advances in asset tracking and ventilation on demand enable this methodology and this study demonstrates that it could represent significant value for mine operators. An examination of haul truck duty cycle indicates that de-rating of engine operating power based on the truck’s location in the mine can enable a step change in ventilation rates, often with no material impact on working conditions. Methods for implementation and estimate of cost savings will be defined.INTRODUCTION Ventilation of underground workings remains a significant operating cost burden for modern mine operators. In particular, ventilation rates for underground diesel mining equipment are often defined by local regulatory bodies and are assumed to present minimal opportunity for optimization or savings, at least until battery propulsion systems can be adopted. Commonly, the quantity of air flow required is defined by the peak rated engine output power of diesel equipment. For example, Ontario Regulation 854 SS 183.1 (3) states that “The flow of air must be at least 0.06 cubic metres per second for each kilowatt of power of the diesel-powered equipment operating in the workplace”. Jurisdictions that define air flow using the prescribed CANMET or MSHA ratings use peak engine emissions to calculate air flow required for dilution ventilation. These approaches are similar in that the maximum power capability of a vehicle’s engine is used to define the ventilation rate in all areas where it travels, regardless of what power output is actually used in any of those areas. Examination of the duty cycle of a typical underground haul truck identifies a large variance in the power output of the vehicle depending on its location in the mine and the activities undertaken at these locations. For example, travel on a mining sub-level requires a fraction of the truck’s peak power due to the minimal grade and significantly reduced travel speed. So if we can reliably reduce the peak engine power capacity and engine emissions in areas where peak power is not required, we can logically cut the ventilation rates for those areas."

Jan 1, 2017

By A. S. MacNeil

In the operation of any colliery, a factor of prime importance is power, of which there are three sources available--man, horse, and mechanical. It is obvious that man-power is by far the most expensive, .and that animal-power, also, is more costly than mechanical. In recognition of this fact, mine owners must, for economical ?reasons, reduce the use of man-and horse-power to the minimum by the increased use of machinery. In other words, they must aim at as complete mechanization as conditions will permit, taking advantage of existing physical factors that are favourable and making the necessary adjustments and modifications to meet the less favourable conditions. Intensive coal-mining, or the concentrated production of coal, has two distinct objectives: First, the maximum production from a limited area, in a given time, thereby reducing the pit-room to be maintained; and second, reduction in cost. To this end the coal should be mined, loaded and delivered to the surface by mechanical means wherever possible. To do this, however, requires the solution of many problems arising out of the varying conditions that obtain underground. The system of longwall mining lends itself to a more efficient scheme of mechanization than does pillar-and-room, as, in the former, the first step has already been taken by the removal of all the coal in one operation, and the opening-out of one face, the equivalent in mining area of fifteen or more rooms. Much has been clone of late towards mechanization in the longwall mines of the Sydney coal-field, and with gratifying results, but not without great difficulties and frequent disappointments. In 1923, an attempt was made with shaker conveyors. The introduction of conveying was a step to bridge the gap between the face, where the coal is produced, and the main transportation arteries leading to the slope or shaft. The receiving of the coal at the faces and its delivery to main loading points on main haulage-ways was the part allotted to the conveyors.

Jan 1, 1932

By R. S. Jones

"Fording Coal Ltd. is now in its fifth year of a 15-year contract to supply 3 million long tons of clean coal per annum to its Japanese steel-making customers. The mine employs both conventional truck-shovel and unconventional ""walking"" dragline coal mining techniques in multiple-seam pits. This paper describes the present and future application of the 60-cu.-yd dragline and truck-shovel pre-stripping fleet in 1•ecovering 5- to 40-footthick coal seams in mountainous terrain. Deep blastholes, coal flow demands, spring ""run-off"", seam and inter-seam thrust faulting, limited seam outcrop data and regional faulting are a few of the problems encountered in this application. The author discusses these problems and their solutions as applied at Fording Coal Ltd."

Jan 1, 1976

By R. F. Lynch, F. E. Goodwin, A. F. Skenazi

"The Gal/an alloy has been developed for continuous galvanizing of steel. The choice of the eutectic zinc-aluminum alloy with addition of misch metal gives a coating with specific characteristics as far as structure, analysis, surface chemistry and surface morphology are concerned. The performance of the uncoated Galfan coating is superior when compared to conventional galvanized particularly for corrosion resistance and ductility. For coil coating applications, these two assets are of the utmost importance but in order to benefit from these two advantages, good paint adherence and high resistance to edge creep and blistering have to be obtained. Despite Galfan's unique features compared to other zinc based or aluminum zinc based coatings, existing pretreatments and painting conditions are used with only minor modifications in order to assure good adherence and edge creep resistance. With compatible processing, Galfan can outperform galvanized and Galvalume as a substrate for coil coating as is demonstrated with various test results.IntroductionThe technical and commercial development of Galfan, a 95% zinc-5% aluminum-0.1% lanthanum-cerium hot-dip coating for steel, has been rapid. From its identification as a promising coating in late 1980, it has evolved from a research product to a fully commercial product with over 100 000 metric tons of coated sheet produced to date, and another 90 000 tons, at minimum, scheduled for 1986. The great majority of tonnage produced to date has been coil coated for use in building panel , appliance, and similar applications. Much technical work has been done to determine the suitability of Galfan for these applications and the proper way of processing sheet for best results. The present state of knowledge is discussed in this paper, along with some recent applications which are given asexamples"

Jan 1, 1987

By M. B. B. Research Council of Alberta Crockford

Introduction Kootenay strata of Lower Cretaceous age contain much of the highest rank coal produced in Alberta. These strata outcrop in the foothills and mountains of southwestern Alberta and southeastern British Columbia, and the economic value of the coal seams contained in them was evident to the earliest explorers, who refer co them in their journals. Lacer, investigation of the .coal measures was undertaken by prospectors and by a succession of geologists, most of whom were in the employ of the Federal government, but some acted for private interests. Surveys by these men proved chat foothills and mountain regions hold immense quantities of high-grade coal within easy reach of transportation facilities, and their conclusions have accelerated the development of the coal-mining industry m Alberta. Among geologists who have contributed much to our knowledge of the region are J. M. Dawson, G. M. Dawson, R. C. McConnell, D. B. Dowling, J. D. Mackenzie, B. Rose, J. R. Marshall, B. Rose, J. R. Marshall, B. R. McKay, J. A. Allan, and J. L. Carr. The present paper is to a great extent a compilation of the work of the above men and of several others who have investigated the area lying between Bow river and Crowsnest pass. Space does not permit a list of all the sources of information so chat only chose of prime importance are given in the text. Data for the map and ?cross-sections of Figure 1 were taken from the following published maps of the Geological Survey of Canada: Cascade Coal Basin, Pub. 933; Canmore, Maps 322 and 323; Upper Elk River and Upper Highwood Rivers, Pub. l980; Blairmore, Pub. 1584; Southfork Coal Area Map l03A; and of the Research Council of Alberta: Highwood-Elbow Area, Map 20; and Ribbon Creek Area, Map 21. In some cases, the cross-sections have been simplified or otherwise altered, and for these revisions the writer cakes full responsibility. The stratigraphic sections of Figure 2 have been taken from published reports of the above mentioned organizations. The area covered in this paper is shown in Figure l. It is wholly within Alberta, and reaches from township 5 to township 27 and from range 1 co range 11, west of the fifth meridian. Its location is about fifty miles west of both Calgary and Lethbridge. Topography of the area ranges from foothill on the east to mountainous on the west. In this paper' the foothill region is considered to be chat which lies immediately east of the most easterly mountain ranges, such as Livingstone and Highwood. There are two principal coal mining districts in the area, one served by the main line of the Canadian ?Pacific railway and centring about Canmore, the other by a branch line of che same railway and centring about Bellevue, Blairmore, and Coleman.

Jan 1, 1949

By G. Tairova, M. Murchie, B. Esford, E. Lam

"The objective of this project is to investigate methods to lower the sulphate concentrations in the mill effluent. Currently, the concentration of sulphate in mill effluent is approximately 2 g/L. The high concentration of sulphate ion in the effluent has the potential to become a regulatory issue. The target sulphate concentration in mill effluent for this work was less than 500 mg/L. The pilot studies, using sulphate precipitation, were carried out at the mill. The results of the sulphate precipitation pilot study, using calcium hydroxide and sodium aluminate, indicated that:• The sulphate concentrations in effluent could be reduced to less than 500 mg/L.• The concentrations of most other elements of concern, such as selenium, arsenic, cobalt, nickel and vanadium, were also reduced.INTRODUCTIONHistorically, the concentration of sulphate, SO4 2-, in water has not generally been subject to regulation. However, with the increasing global consumption of water, stricter regulations on sulphate quantity may be imposed. Sulphate is a concern in process waters as it forms scale on process equipment and leads to operational problems. High sulphate concentrations may result in adverse health effects. The taste theshhold for the most sulphate salts in drinking water ranges from 250 to 500 mg/L.A literature search and review to identify methods to reduce sulphate concentration in the mill effluent was carried out. A number of methods were selected and tested in the lab. The experimental results indicated that the precipitation methods, using calcium hydroxide and aluminum compounds, barium compounds, as well as the ion exchange and the membrane methods, were effective for the removal of sulphate to below the required limits. Some other elements, such as vanadium, nickel, cobalt, selenium and molybdenum, were also removed.The process, using calcium hydroxide and aluminum compound for sulphate precipitation, similar to the Cost Effective Sulphate Removal (CESR), also known as “Walhalla” process, described in the Montana Tech report (“Demonstration Of Sulfate Removal” 1999), was selected for further consideration [1]. In the CESR process, the water is treated with lime for precipitation of gypsum, followed by the reaction with a proprietary aluminum compound for removal of a residual sulphate. The final pH adjustment is carried out using carbon dioxide. Results of a preliminary cost estimate indicated that the removal of sulphate using calcium hydroxide and aluminum compound was the preferred method of treatment, considering its low cost, availability of chemicals and minimal changes to the existing plant circuit."

Jan 1, 2012

By Martin Stoklossa

Surface mining operations typically require run-of-mine material to be sized for further processing. In-pit crushing facilities serve this need, as stationary, semi-mobile or fully mobile units. Although in particular fully mobile crushing facilities have been in use for over half of a century, other surface mining techniques have typically been implemented. However, with increasing operating costs in truck and shovel operations, and other economic considerations, mobile crushing plants are increasingly a viable option. The operational and economical parameters in relation to the optimal surface mining equipment selection will be reviewed. The role of the mobile crushing technology within the continuous vs. noncontinuous surface mining operation and basis for mine planning are also discussed. Current applications and respective case studies will be reviewed. Key performance indicators will be presented. These performance parameters can be viewed as a tool to aid in the equipment selection process. The future direction for further research and development in mobile crushing facilities will also be presented.

May 1, 2008

By G. G. Bowser

PERUSAL of a list of present-day commercial explosives perhaps does not convey a full realization that there has been a great deal of improvement since the original dynamite was discovered nor that, in recent years, great developments have taken place in specialized explosives. This is true particularly of high-explosives for use in metalliferous mining or what is more commonly termed 'hard-rock' mining. Not many decades ago, only two or three types of explosive were avail-'able for commercial use. One was black blasting powder. Another was ordinary nitro-glycerin dynamite in various strengths. Black blasting powder remains with but very little change. Despite its ancient lineage, it is still with us as perhaps the sole explosive in use today which is almost identical in appearance, physical properties, and working ability or execution co the original. Which dynamite the story is different. Its evolution may be likened to that of the dog, nitro-glycerin as first discovered being the counterpart of the wild dog and, like it, dangerous and hard to control. The original dynamite as made by Nobel might then be considered as representing the first domesticaced species. This original dynamite, however, has been 'crossed with other bloods' until one sees now many distinct 'breeds' in the list. Present-day explosives still have the 'bark' and the 'bite', but with control and research have come many improvements; and types have been created which are specially adapted for particular kinds of work. We still have the direct descendant of Nobel's dynamite in the form of an improved nitro-glycerin dynamite. This C-I-L explosive, Polar Dynamite, is no longer the best type to use in the hunt for gold, silver, iron, and other metals. There have been developed other explosives more suitable for chat work. In Canada, such explosives are accomplishing this work effectively, not only where climatic conditions are moderate but through the rigours of our northern winters, with their sub-zero temperatures.

Jan 1, 1938

By D. G. Crosby

This paper defines the Canadian offshore areas, comparing the juridical continental shelf with the physical one. The question of jurisdiction and ownership is dealt with, and the setting out of resource administration lines to divide areas of federal and provincial administration is explained and illustrated. Offshore activity is reviewed and prospective areas for future work are mentioned.

Jan 1, 1969

By Clermont Lavoie, Marc Filion, Marcel Vallée

"Les mineralisation d'or des gîtes de la SOQUEM - Silver Stack dans is canton Bousquet se situent dans une bands de roches pyroclastiques asides du groupe de Blake River, d'âge archéen, dans le même horizon géologique que lee gites aurifères de Thompson Bousquet et Dumagarni situés plus a rest. La propriété a été explores anterieurement a maintes reprises depuis les années 1930, parfois jusqu'aux travaux souterrains, notamment par les groupes Mooshla, Warrenmac et Westwood Cadillac ainsi que par Silver Stack Mines.Ces zones auriferes se situent a l'intérieur de larges halos (jusqu'à 1,000 m x 400 in) de pyrite disséminée (2-5%) dans des tufs a lapilli et des agglomerate acides montrant des concentrations locales de pyrite. La zone 1, découverte en vérifiant par sondage une anomalie E.M., coincide avec une de ces concentrations de pyrite et la teneur en or est ici proportionnelle a la pyrite. Ce secteur se distingue par l'intensité de l'altération en séricite. La zone 2, qui s'étend sur près de 600 m, se situe dans un agglomérat acids, avec une faible teneur en pyrite, et montre de fines veinules de quartz-carbonate.Du point de vue géophysique, aucune methods ne donne des résultats probants: la polarisation provoquée montre de tree grandee anomalies correspondant aux halos de pyrite, tandis que lee concentrations de pyrite détectées par les méthodes E.M. (VLF ou EMH) sont loin d'être toutes aurifères. Les relevés magnétiques aident a établir la structure la où un certain contraste de susceptibilité magnétique est present. Les essais minéralurgiques préliminaires indiquent que la concentration de Bette mineralisation aurifère ne présentera pas de problems majeur."

Jan 1, 1977

By H. J. McQueen

ORDER OF PRESENTATION ?INTRODUCTION TO THE VICTORIA BRIDGE ?REASONS FOR A BRIDGE AT MONTREAL ?RAILROAD BRIDGE REQUIREMENTS ?IRON PRODUCTION CANADA / WORLD AL ?METALLURGICAL INDUSTRY CANADA ?FAIRBAIRN, STEPHENSON SHIP PLATE-RIB BOX GIRDER ?VICTORIA BRIDGE (PREFABRICATED BRITAIN) ?IRON ORE SITUATION THE VICTORIA BRIDGE 1859, TUBULAR -WROUGHT IRON* 1898, TRUSS ?STEEL* (*HOT RIVETED) 1957, SPUR, LIFT SPANS ??DUCTILE WROUGHT IRON WITHSTANDS FATIGUE ?TO KEEP THE TRAINS ON TIME & ON TRACK? ??IMMOVABLE SHARP PIERS SPLIT ?THE IRRESISTIBLE ICE, STOPPED CITY FLOODS? ? ?********* ??111 YEARS-YOUNG STEEL TRUSS, (1898): ?STILL VITAL SEA-T0-SEA RAIL LINK? ? ?********* ??51 YEARS HAVE PASSED SINCE SEAWAY (1958) ?SWITCHED BRIDGE INTO DOUBLE LIFT SPANS?

May 1, 2011

By J. -F. Lessard

Most underground mines rely on ore pass systems to ensure the transport of ore and waste. The design and operation of ore pass systems often rely on past experience, which is often anecdotal and at times contradictory in nature. This paper summarizes the current practice in Quebec underground metaliferous mines. The information was collected during a series of site visits in ten underground mines. The database includes information on ore pass configuration, support, materials transited, and overall ore pass performance.

Jan 1, 2006

By Steven W. Wilson, Brigitte Lacouture, Nichola A. McKay

"The Aqqaluk deposit is a lead-zinc ore body that lies immediately north of the Main Pit at Teck Cominco’s Red Dog Mine in Alaska. It is scheduled to begin production in 2011 or 2012. A project team was formed in late 2004 to plan and implement an ore characterisation and metallurgical evaluation on the Aqqaluk ore. The main objective of this program was to facilitate the transition from Main Pit to Aqqaluk ore in the Red Dog concentrator. The program will develop a detailed, spatially-oriented characterisation of the Aqqaluk deposit attributes including lithology, ore geochemistry, bulk mineralogy, ore texture, as well as evaluating the metallurgical characteristics of ore hardness, process water geochemistry, bench-scale floatability and mineral liberation in ground feed, concentrate and tails. Developing correlations between the metallurgical response and the ore characterisation data is key to the emerging science of geometallurgy. This on-going program is a technical due diligence study that aims to reduce the risk associated with processing a new ore and to provide predictive information for mining and stockpile preparation.The test work to date has focused on characterising the five ore zones currently identified in the Aqqaluk deposit, namely: Siliceous (sub-divided to High Zn:Fe and Low Zn:Fe), Vein, Median Plate and Baritic ores. It identified a number of challenges associated with surface oxidation, or weathering, of the core samples and outlined a program for future sample collection and storage. Metallurgical testing evaluated ore hardness by a variety of methods. Preliminary floatability studies have been completed and some initial links have been established between the ore characteristics and the flotation response. Soluble mineral weathering products, the relative abundance of pyrite and marcasite and the iron content in the sphalerite grains have all shown a correlation to mineral recovery.As new core is received, both the ore characterisation and the metallurgical testing will be continued with a view to strengthen the existing correlations and develop new links."

Jan 1, 2007

By T. D. Chatwin

While new jobs and taxes are major incentives for support of mining, stakeholders must also be assured that current jobs, resources and environment will be protected. Mining companies can help achieve stakeholder support by frankly addressing Acid Rock Drainage CARD) issues. To prevent ARD, miners must begin early in the mine life-cycle to develop an ARD management plan and integrate it into the mining operation. As this proactive preventative program is initiated, mining companies also need to engage and collaborate with stakeholders to insure that their expectations and needs are met. Stakeholder engagement is enhanced as mining companies emphasizes the value of clean and available water for current and future generations.

Jan 1, 2011

By D. Ortiz, J. R. Frias, E. D. Mast, J. J. Fañas

Falconbridge Dominicana (Falcondo) has operated an integrated tpy nickel laterite mine and ferro-nickel processing plant since 1972 in the Dominican Republic. The operation includes mining, a processing plant, an oil refinery, and a power plant. Falcondo has improved process efficiency over the years via modernisation and better understanding of the process. The present business environment of high fuel prices and high nickel prices present a challenge and an opportunity to Falcondo's operation. This paper gives an update of Falcondo's process, improvements in energy consumption, factors affecting energy consumption and how Falcondo is facing up to the current business environment.

Jan 1, 2005

By J. Budac, R. Kofluk, D. Belton, M. Sjogren

A series of tests were performed to determine the flammability limits of mixtures of oxygen, ammonia, steam and nitrogen, over a solution, in a sealed autoclave. The partial pressures of ammonia and oxygen in the vapour space were varied by adjusting the character of the solution and by adjusting the oxygen concentration in the oxidant gas respectively. The data shows that flammable conditions can be minimized by controlling the operating temperature, reducing the ammonia content in the solution, increasing the concentrations of Ni, Cu and Zn in solution and keeping the % oxygen in the gas phase less than 15.5. Observations were also made that suggest that the presence of an aerosol in the vapour space may hinder ignition.

Jan 1, 2004

By L. Chunpongtong

One of the challenges of mine planning is to determine the most cost-effective replacement time for aging equipment. The lifespan of equipment, such as haul trucks and shovels, deployed in mining operations varies due to the nature of the material and ground conditions in which it operates. For engineering economists dealing with aging equipment, the options become an economic trade-off between higher maintenance cost versus the cost of new equipment. The discount rate plays a significant role in this decision; the higher the rate, the longer the economically optimal lifespan. Therefore, the ultimate question is: ?How can the relationship between the discount rate and the economically optimal lifespan be expressed mathematically??

Aug 1, 2013

By Andrea Lisjak Bradley

Clay shales are currently being assessed as possible host rock formations for the deep geological disposal of radioactive waste. However, one main concern is that the favourable long-term isolation properties of the intact rock mass could be negatively affected by the formation of an excavation damaged zone (EDZ) around the underground openings. The goal of this thesis was to develop and validate a mechanically-based model of the deformation and failure process of a clay shale, namely Opalinus Clay (OPA), with particular focus on the influence of anisotropy on the short-term response of circular tunnels. To achieve this goal, a hybrid continuum-discontinuum numerical approach was developed in combination with new field measurements from the Mont Terri underground research laboratory. The response of OPA during the excavation of a full-scale emplacement (FE) test tunnel was characterized by geodetic monitoring of wall displacements, radial extensometers and longitudinal inclinometers. The deformation measurements indicated strong directionality induced by the combined effect of in-situ stress field and bedding planes striking parallel to the tunnel axis, with the most severe deformation occurring in the direction approximately perpendicular to the material layering. Computer simulations were conducted using a newly-extended combined finite-discrete element method (FEM/DEM), a numerical technique which allows the explicit simulation of brittle fracturing and associated seismicity. The numerical experimentation firstly focused on the laboratory-scale analysis of failure processes (e.g., acoustic activity) in brittle rocks, and on the role of strength and modulus anisotropy in the failure behaviour of OPA in tension and compression. The fracturing behaviour of unsupported circular excavations in laminated rock masses was then analyzed under different in-situ stress conditions. Lastly, the proposed modelling methodology was applied to the aforementioned FE tunnel to obtain unique insights into the EDZ formation process around emplacement tunnels for nuclear waste. The calibrated numerical model suggested delamination along bedding planes and subsequent extensional fracturing as key mechanisms of the damage process potentially leading to buckling and spalling phenomena. Overall, the research findings are already having a direct impact on the preliminary design process of an underground repository for nuclear waste in Switzerland.

Jan 1, 2015

By Frederick J. Browne

Water, water everywhere, but not a drop (fit) to drink! Trite, but how often only too true? What is there met with in mining which, under various circumstances, may be said to be the most sought-for and highly-prized and also the most objectionable and most feared? Water! What visions that combination of five letters brings to all thoughtful minds? Up to near the end of the eighteenth century water was thought lo be an element but was then discovered to be the result of the combustion of two volumes of hydrogen with one volume of oxygen, and water so produced is chemically pure. Pure water is a clear and colourless liquid when seen under ordinary conditions, but appears bluish when seen through a long tube, and this same bluish tint may be observed in many lakes, especially those of glacial origin. A story often told describes a prospector in the desert who, failing to find water to replenish his canteen, suffers torture and death under fearful circumstances. Then again we may recall the flooding of mines, where water poured in so quickly that there was no opportunity of saving the unfortunate workmen. Instances might be multiplied without number showing that either the lack or excess of this essential fluid has taken heavy toll of human life. In all branches of mining and associated industries water must be dealt with to a larger extent, from an economic point of view, than any other substance, and very often the purity of the water is a matter of considerable importance.

Jan 1, 1925