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By John L. Lamont, Walter Craft

Adequate hardenability has long been recognized as one of the first requirements for producing desired mechanical properties in a heat-treated steel. Since the introduction of the Jominy end-quench test' and the development of correlative information to expand its use, industry has had an effective measure of hardenability. Prediction and control of the hardenability have been made possible by Grossmann's principle2 for calculating hardenability from chemical composition; and Field's conversiona from depth of half-martensite hardening to Rockwell C hardness has made the relation more quantitative. These developments have facilitated the design of new steels and the control of standard grades to the extent that it has been possible to establish tentative hardenability bands for some of the more commonly used alloy steels.4 As the depth of hardening of the Jominy test specimen is usually measured by Rockwell C hardness, it was considered that it should be possible to predict the hardness by a more direct calculation. It has been found that this can be accomplished by the addition of Rockwell C units proportional to the carbon and alloy content, grain size, and position in the Jominy test specimen. The calculation has been found to be fairly accurate, and because of its additive character is relatively simple to use. In principle the method of calculation is somewhat similar to the expressions developed by Herty, McBride, and Hollen-back,5 Burns, Moore, and Archer,= and Burns and Riege1.l The calculation is started from a base that includes the effects of carbon content and position in the Jominy test speimen. Rockwell C units are added to the base in proportion to the alloy content and grain size. This sum represents the Rockwell C hardness up to the level at which a disproportionate increase of hardness is caused by the formation of martensite, and above this level an increment for martensite hardening is added. The effects of alloys are directly proportional to the amounts present and are independent of each other, the carbon content, and the position in the specimen. Furthermore, the factors for determining the martensite increment are dependcnt only on carbon content and are independent of cooling rate and alloy content. It is this absence of interrelation between the different factors that makes it possible to calculate the hardness and makes the method of calculation consistent with the principle that the character of the hardening reaction is governed primarily by carbon and that alloys exert their effect chiefly through control of the critical cooling rate. The principle of the calculation, and the effects of alloys on the critical cooling rate,

Jan 1, 1947

By Georgc E. Collins

SEVERAL years ago, I estimated the total stock of gold in the world to be about a thousand million ounces, of which rather over one-third was available for monetary uses. Robert H. Ridgway has estimated the world's production from 1493 to 1927 as slightly over this amount. Of this total, 1.5 per cent was produced between 1493 and 1850 (before the Californian and Australian goldfields began to flood the world with gold), 331/2 per cent from 1851 to 1900, and 511/2 per cent from 1900 to 1927. Allowing for loss by attrition and permanent consumption in the arts, and for loss of buried treas¬ure, my first-mentioned estimate is perhaps not far from the truth; but my estimate of the monetary stock was certainly too low. Of the total production stated by Rid-way. 28 per cent came from North America. 26.9 per cent from Africa, 1.6.8 per cent from Australasia, 12.4 per cent from South America, and 11.2 per cent from Asia. Excepting that from the African conglomerate beds, the ultimate origin of which is still the subject of controversy, by far the greater part of the total production was derived from alluvials. Weighing all contingencies, it is improbable that any such production as has been made during the last forty years will be repeated in any similar period, if the present price level is maintained. The gold standard today seems firmly established except for temporary digressions. Nevertheless, no well-informed mining engineer will venture to assert the probability that the material for its maintenance throughout future generations can be furnished.

Jan 1, 1932

By R. K. Hopkins

Fox a great many years fusion welding has been used in and around petroleum refineries, but it is only within six or seven years that the more important pressure vessels have been constructed by this process, because before that time the properties of fusion welds would not withstand such rigorous service. Since the adoption of fusion welding for the construction of this equipment, the refiner has required pressure vessels suitable for operation over a very wide range of conditions. On the one hand, vessels must operate at extremely high temperatures, in the range of 950° to 1000° F., and on the other vessels must be suitable for operation at sub-zero temperatures down as low as -75° F. Also, vessels are required suitable for operation at pressures upwards of 1000 lb. per sq. in., and as low as a 29-in. vacuum. In addition, vessels are required to withstand the attack of very corrosive mediums. It has been a rather difficult task for the fabricator to meet all of these requirements, but as a result of the extensive research carried on by steel manufacturers and several fabricators of class I vessels, practically all of these demands have been met. In order to meet the refiners' requirements for this wide range of conditions, the fabricator has worked closely with the metallurgist. This has enabled him to choose the proper base metal for each service condition, but it has been the fabricator's problem to develop a welding rod and welding technique, as well as a heat-treatment, that would produce in the welded vessel characteristics in and around the weld comparable to those in the base metal. Where corrosion is not a serious problem, and where the operating temperatures are not too high, ordinary carbon steel has served very well. But when corrosion is serious, and/or when the temperatures are either very high or very low, it is necessary to use some form of alloy steel to give satisfactory service.

Jan 1, 1935

By B. W. Frazier

This interesting application of the laws of thermodynamics to metallurgical practice has not been discussed by any writer, within my reading, except the late Prof. Callon of Paris. In his Cours de Machines," Prof. Callon has given a short but lucid discussion of this subject in the admirably clear style for which he was remarkable. Although the interest attached. to the subject is rather theoretical than practical, I have thought that an attempt to explain the mechanical action exerted in the hot-blast oven might not be entirely devoid of utility, especially in the suggestions which it involves. The statement, that the mechanical work performed in heating the blast is, when high temperatures are produced, considerably greater than the work performed by the blowing-engine, may seem incredible to many who are practically acquainted with the subject, appearing, as it does, to conflict with the results of their experience. It is, nevertheless, literally true, and I shall attempt in this paper to prove it, and to explain why it has not rendered itself palpably manifest in practice. Before proceeding to the mathematical demonstration, it will be well to recall to mind the definitions of some terms employed by writers in mechanics and thermodynamics. The actual energy of a moving body, as defined by Rankine, is the work which it is capable of performing against a retarding resistance before being brought to rest, and is equal to the energy which must be exerted on the body to bring it from a state of rest to its actual velocity. The value of that quantity is the product of the weight of the body into the height from which it must fall to acquire its actual velocity.

Jan 1, 1879

By C. J. Osborn

The temperature dependence of the free energies of formation of metallurgically important oxides, sulphides, chlorides, carbonates and sulphates is presented graphically, whereby the task of deriving practical metallurgical information is greatly simplified. The diagrams have been revised according to the latest available thermodynamic data. WHILE it is true that much careful investiga-tional work remains to be done, there are already available in the literature sufficient thermo-dynamic data to enable the metallurgist to predict with reasonable confidence the equilibrium conditions to be expected in most important, and potentially important, metallurgical reactions. In this connection, the careful, critical compilations of K. K. Kelley and his collaborators in numerous U. S. Bureau of Mines Bulletins are particularly valuable. However, the translation of reliable thermo-dynamic data into metallurgical language unfortunately involves lengthy manipulations of the cumbersome formulas which can be set up from heat of formation, entropy, and heat capacity data. Many years ago, Kelley20 predicted that thermo-dynamic calculations would be made in the future "with the aid of free energy, heat content, and entropy tables, rather than by means of the algebraic methods employed at present", and where such tables are available they greatly simplify the task of deriving practical metallurgical information. However, in addition to these tables, there are also available one or two reliable graphical presentations, particularly of free energy data, which may be used in the same way as the tables, but which have the added advantages that interpolation is never necessary, and that the behavior of different metals or compounds may be compared at a glance. Some years ago Professor Robert Lepsoe, Head of the Department of Metallurgy at Norways Institute of Technology (N.T.H.), began a compilation of curves showing the temperature dependence of the heat contents of the elements, and the heat contents and heats and free energies of formation of the common metallurgical compounds. With such a compilation, the thermal and free energy requirements of a reaction may be read from curves in a matter of seconds; and this statement applies not only to the formation of compounds from their elements, and to the reverse dissociation, but to any reaction involving substances whose thermodynamic properties are available. This follows from the fact that heats and free energies of formation are completely additive. For example, the free energy change associated with the chlorination of a metallic oxide at any temperature, T, is given by the free energy of formation of the chloride at temperature T minus that of the oxide also at T; both of these quantities may be read directly from curves of the type suggested above. Since this early, unpublished work of Lepsoe, both Ellingham7 and Richardson and Jeffes46 have

Jan 1, 1951

By Milton C. Head, Aulton E. Roland, William E. Hawes

INTRODUCTION Uranium mining in the Grants Mineral Belt has undergone changes from methods pioneered during the 1950's and has now become fairly standardized throughout the district. The orebodies vary in size and shape and have been most successfully mined by using modified room and pillar methods with pillar recovery. This paper will expand on methods and equipment that are being used and modifications of these that will increase productivity and efficiency. GEOLOGICAL BACKGROUND The petrology of the Grants Mineral Belt consists of alternating layers of sandstone and shales (mudstone), with occasional thin layers of coal. The sandstones are aquifers which are generally artesian to some extent. The shales are bentonitic and decompose into extremely sloppy mud when exposed to water. Figure 1 shows a typical geologic section. Most of the uranium produced in the Grants Mineral Belt comes from the Westwater Canyon member of the Morrison Formation and occurs as scattered ore bodies throughout the formation. This formation consists of layers of bentonitic shale and sandstone of varying degrees' of cementing and grain size. It is also a very significant artesian aquifer. The unconfined compressive strength of the various formations is not high, as shown in Table I. It is important to note that these represent average values and a great range may exist within a single formation, especially In the Westwater which is the ore formation. [ ]

Jan 1, 1982

By R. J. Wagner, G. H. Gronhovd, A. J. Wittmier

The paper describes the results of a series of full-scale boiler tests run to determine the ash fouling characteristics of a North Dakota lignite as a function of sodium content of the coal. Four levels of sodium were investigated and rate of fouling was determined both by boiler performance and by specially constructed probe equipment. Discussed is information on chemical and physical properties of the ash deposits. The vast lignite deposits in North Dakota are becoming increasingly important as a source of low-cost fuel for power generation. A new 200-megawatt lignite-burning plant located near Stanton, N.D., was placed in operation early in 1966. Another 172-mega-watt unit in the same area is scheduled for operation late in 1966, and plans have recently been announced for a 212-megawatt unit to be in operation by 1970. If these plants show good performance, western North Dakota could become a major power production center for a large geographic area in the upper midwest. One of the problems associated with the use of lignite in power boilers is its tendency to form troublesome ash deposits on boiler tube surfaces. This problem varies considerably from one lignite-fired boiler to another and is dependent upon such factors as source of lignite, boiler design, load factor, tube metal temperatures, and soot-blowing practices. This report presents data on sodium content* variation in a North Dakota mine, describes the results of a series of tests performed to determine the relationship between ash fouling tendencies and the sodium content, and tells how the mining company and electric utility have coordinated their operations to reduce the ash fouling problem. GENERAL BACKGROUND Until recent years it was generally assumed that North Dakota lignite from a given mine had qualities peculiar to that mine, but that within the mine, the lignite was quite uniform. In 1959, the Otter Tail Power Co. installed a 53.5-megawatt lignite-burning unit at its Hoot Lake plant, Fergus Falls, Minn. Shortly after the unit was put into operation, it was noted that at certain times under high load conditions, ash fouling problems were quite severe, but not consistent or predictable. Each time fouling occurred in the unit the position of the loading shovel at the mine was noted. Within two years it became apparent that there were certain areas in the Knife River Coal Mining Co. mine at Beulah, N.D., where the lignite apparently had a high fouling tendency for the Hoot Lake unit. Results from analyses of the coal did not show large differences in moisture percentage, ash percentage, heating value, or ash fusion temperature between the highly troublesome and less troublesome coals. After three years of operation, the troublesome areas had been quite well defined and the mining company started a procedure of bypassing these areas when load conditions at the plant were high and then returning to the troublesome areas to load the lignite during the summer months when peak loads were lower. It was noted that the lignite from the areas which caused severe fouling under high load conditions produced much less fouling at the lower summer loads. However, bypassing certain areas in the strip pit caused the mining company to disrupt their continuous loading schedule, which in turn upset their continuous stripping schedule and made for less efficient mining operation. Meanwhile, at the Hoot Lake plant, the number of soot blowers on No. 2 boiler had been increased from 30 to 55, and a very rigorous blowing schedule had been adopted resulting in soot blowers operating at least some part of 21 hrs per day. Fouling problems continued, with a resulting reduction in plant economy and reliability. During this period the Federal Bureau of Mines Coal Research Laboratory at Grand Forks, N.D., had initiated various research programs relating to the study of lignite ash and ash fouling problems. One project was a survey in which full seam samples were obtained from various locations in all the major

Jan 1, 1968

By Olaf B. Slostad

ONE of the essential functions of any modern community is to provide a fully accredited public school system. The Climax Molybdenum Co. was cognizant of this fact and erected a modern school building in 1937 to meet this need. The building was named after the president of the Company, Max Schott, who was largely instrumental in making it a reality. The building is a two-story brick structure with fourteen rooms, eight of which are regular classrooms. The others consist of a room for industrial arts, two for home economics, one for commercial arts, one for a science laboratory with a dark-loom for photography, and one large room for a combination library, study hall, and assembly room. All these are equipped with the most up-to-date modern equipment. The school is fully accredited by the University of Colorado. Although in a mining camp, it operates as a public

Jan 1, 1946

By Magnus Troilius

SINCE the discussion on steel rails in America has forcibly drawn attention to the value of chemical analysis, if not as a necessary stipulation, at least as a guide to control the usual mechanical tests, some doubt has been thrown upon the accuracy of the analytical results obtained by different chemists. To any one having the least acquaintance with chemistry, it is quite clear that if exactly similar results are to be obtained from the same borings of steel, exactly the same methods must be used by the different analysts. Hence the necessity (if complications are to be avoided) of establishing what I may call standard or normal methods, to be used both by the inspectors and by the chemists at the works. Remembering that the application of chemistry to steelrail inspection is yet in its infancy, it is of great importance to possess a perfect acquaintance with the best methods in use. Being myself a grateful pupil of Professor Eggertz, of the School of Mines in Sweden, it occurred to me, two years ago, that I could not do better than start a laboratory of my own, and engage one of his pupils, Mr. Troilius, for the purpose of analyzing the steel borings from mechanically-tested rails, so that I might thus obtain without delay thoroughly accurate determinations. Moreover, in order to carry on the operations in perfect accordance with the methods used at the steel works in England and Germany, where I had to control the manufacture, I deemed it desirable to allow Mr. Troilius to go through a course of training at these works; and I gladly seize this opportunity of expressing my grateful acknowledgments to several works in England and in Germany for affording every facility for such an exchange of information as mas found necessary in arriving at the best analytical methods to be used.

Jan 1, 1882

By G. D. Just

INTRODUCTION Large scale underground mining involves the bulk handling of fragmented material. The cost and efficiency of the mining systems is there- fore significantly influenced by material flow characteristics. Flow problems may occur in the form of ore pass blockages which interrupt the free flow at extraction openings. The costs of such delays can be readily assessed and compared to the costs incurred in reducing blockages by improved fragmentation or larger ore passes. In practice the problem is more complex than this statement suggests because it is generally un- economic to design for zero ore blockages. Another major flow problem occurs in the form of relative movement of ore and waste as the fragmented material is extracted. This produces waste dilution in the recovered ore and influences total ore recovery. This flow problem is much more complex than the ore block- age phenomena. Many questions concerning the precise flow characteristics remain unanswered because of the variability of size distributions, particle shapes, material properties and the total extraction layout and design. Model studies can provide a visual and quantitative illustration of probable flow characteristics but full scale data collection is necessary to evaluate the precision of such information. The methods and types of data obtained must be carefully selected to recover the maximum volume of useful information for operational control and future design. It is essential that honest precision levels are assigned to the data and any subsequent analyses. Grade control data may give misleading short term information on flow characteristics because of the difficulty in knowing the true grade of the mass of material before extraction commences. However, in the long term control of extraction grades is vital to the profitable operation of the mining system. The most efficient extraction design and operational schedule can only be determined after all of the facts and variables are known. This is usually only possible after the orebody has been completely extracted. However, if design and operational personnel have a full appreciation of the nature and variability of material flow under different conditions the best possible results should be achieved. The most significant features of material flow are out- lined in this paper in order to provide mine planning and mine management personnel with some of the necessary information relating to material flow. Available facts and reliable figures from selected publications are noted in association with unbiased and hopefully accurate opinions of the relevance of the data to mine design and mine system control. Possible future developments and profitable areas for research into material flow problems are also detailed. MATERIAL FLOW AND MINING METHODS The effects of material flow on the design and operation of an integrated underground ore handling system is one factor which is common to most mining methods. Analysis of the system as detailed by Just, 1980, permits the identification of unit process objectives. For example, a typical underground ore handling system as illustrated in Figure 1, involves the following unit operations:- (i) Gravity flow of ore in stope (ii) Ore extraction at base of stope (iii) Ore haulage on the production level (iv) Dumping of ore into ore pass system (v) Gravity flow of ore in the ore pass (vi) Underground crushing of ore (vii) Haulage of crushed ore to shaft (viii) Hoisting of ore to the surface. Average flow rates in each of these unit operations can be misleading due to variability in incremental capacity caused by flow blockages and machine delays. Thus to effectively analyse the probable performance of the system, it is necessary to have a measure of the flow loading and haulage rate variability. Mechanical equipment performance specifications can be used to provide such information for loading, haulage and crushing; however, in the case of the gravity flow of material field measurements are required to relate the probability of "hang-ups" to the degree of fragmentation. Factors affecting the frequency of flow stoppages are, size, distribution and cohesiveness of broken material and the geometry and size of the flow channel. Ore pass channel design is relatively simple since regular cross-sectional shapes are used

Jan 1, 1981

By E. F. Kingsbury

ONE of the well-known and important uses of the noble or precious metals has been for electrical contacts. In fact, the elements of this group, comprising gold, silver and the six platinum metals, have been called "noble" because of their ability to resist- heat and corrosion, properties which were early found to be of importance in good contacts. Of these, platinum and its iridium alloys, palladium, and silver, have been extensively used. In recent years the electrical industry has been responsible for about one-eighth of the total consumption of the platinum metals in the United States. Information is not available as to what part of this one-eighth has been used for contacts but it is certainly an important one. SUBSTITUTES FOR PLATINUM During the past 20 years a considerable number of contact alloys have been proposed in the patent literature largely with the aim of more or less replacing platinum by gold or silver, and some of these alloys are finding increasingly widespread application as the reliability of their performance becomes established.. From even the partial data at hand it appears that this substitution by the less precious metals has replaced at least one-half of the amount of platinum that the entire electrical industry would otherwise be consuming at the present time.

Jan 1, 1928

By Edward H. Robie

Jan 1, 1971

By F. D. DeVaney

IT is of great interest that the various organizations engaged in the search for a cheap and efficient agglomeration process for fine magnetite concentrates-essential if the taconites are to be utilized-have ended up with processes that are basically different. This paper describes the development and the present status of the shaft-type furnace as now utilized by the Erie Mining Co., which is managed by Pickands Mather & Co. The shaft furnace has always had an appeal to metallurgists because of the simplicity of the design and the possible low fuel consumption. Work done on pelletizing at the University of Minnesota Mines Experiment Station by E. W. Davis and his associates determined that it was possible to roll up fine magnetite concentrates in a balling drum, and that, if such balls were fired at a sufficiently high temperature, a hard, indurated pellet, well adapted for use in a blast furnace, could be made. Early furnaces had no heat recuperation and the heat consumption was in the order of 2 million BTU's per long ton.

Jan 3, 1958

Jan 1, 1920

By R. J. Corfield

MODERNIZATION of the entire electrical system and improvement of Rotation process efficiency is the twofold goal of the improvement program underway at the Arthur and Magna concentrators of the Utah Copper Div., Kennecott Copper Corp. Copper ore from the Bingham pit goes to these two concentrators where an interlocking program calls for complete electrical modernization and increased flotation process efficiency through additional capacity and flow scheme revisions. Flotation plants at the two mills are essentially duplicates, and while this article deals with the changes at the Arthur mill similiar improvements are being made at the Magna mill.

Jan 3, 1953

By P. H. Brace

THE study of the relations between gases and metals is one of perennial interest to all who are connected with the production of high-grade metallurgical products. The data reported here are the outcome of work of which the object is to determine the effects of dissolved gases upon the properties of metals and to gain a more detailed knowledge of the reactions between gases and molten metals, particularly; iron, under definitely controlled conditions. We have attempted to reduce our margin of error by dealing with relatively large quantities of metal, from 4 to 13 lb. (2 to 6 kg.), and keeping the ratio of refractories to metal as small as practicable. The ingots produced are large enough to provide adequate material for making determinations of magnetic and other physical properties. In choosing the bell-jar type of furnace we were influenced by the results of considerable experimentation along the same general line which indicated that, for the scale or which we were to work, it was important to have the furnace structure independent of the vacuum enclosure. The use of a bell-jar surrounding the entire furnace accomplishes this and also gives great freedom of observation during operation and ready accessibility for the replacements which are necessary after each run. Our choice of analytical method was made in the light of the results secured by H. M. Ryder, who used a method similar in principle for the analysis of very small quantities of gas extracted from strips of metal heated electrically in high vacuum. We have presented some selected preliminary experimental data as being illustrative of the quantity and nature of the gases which occur in iron of different origins, but do not urge any hypothesis at this time.

Jan 1, 1928

By P. H. Brace

THE study of the relations between gases and metals is one of perennial interest to all who are connected with the production of high-grade metallurgical products. The data reported here are the outcome of work of which the object is to determine the effects of dissolved gases upon the properties of metals and to gain a more detailed knowledge of the reactions between gases and molten metals, particularly iron, under definitely controlled conditions. We have attempted to reduce our margin of error by dealing with relatively large quantities of metal, from 4 to 13 lb. (2 to 6 kg.), and keeping the ratio of refractories to metal as small as practicable. The ingots produced are large enough to provide adequate material for making determinations of magnetic and other physical properties. In choosing the bell-jar type of furnace we were influenced by the results of considerable experimentation along the same general line which indicated that, for the scale or which we were to work, it was important to have the furnace structure independent of the vacuum enclosure. The use of a bell-jar surrounding the entire furnace accomplishes this and also gives great freedom of observation during operation and ready accessibility for the replacements which are necessary after each run. Our choice of analytical method was made in the light of the results secured by H. M. Ryder, who used a method similar in principle for the analysis of very small quantities of gas extracted from strips of metal heated electrically in high vacuum. We have presented some selected preliminary experimental data as being illustrative of the quantity and nature of the gases which occur in iron of different origins, but do not urge any hypothesis at this time.

Jan 1, 1928

By R. R. Seeber

(Pittsburg Meeting, March, 1910.) IN the copper-mining district of northern Michigan a fair-sized mine usually operates two or more shafts along the strike of the lode, these shafts being usually at least 1,000 ft. apart. The tonnage to be hoisted from each shaft is large-from 13,000 to 25,000 tons per month. The hoisting-engines used are generally steam-driven, non-condensing, duplex engines with Corliss valves, supplied by steam from separate boiler-plants where the distance between shafts is great. In an attempt to centralize power-plants and secure central-station economies, the Winona Copper Co. installed an electric hoist of the Ilgner type, with Ward Leonard control. A brief description of this plant has already been published.1 The only point of variation from the simple Ilgner set lies in the connection of two generators to a single induction-motor by flexible couplings. These generators serve motors which operate hoisting-drums at separate shafts, viz., No. 4 shaft, Winona, and No. 1 shaft, King Philip. , The hoist for No. 4 shaft, is about 1,700 ft. from the power-plant, and in this building the motor-generator set is placed. No. 1 King Philip hoist is 1,500 ft. from the motor-generator set. The equipment of the motor-generator set is as follows: In the middle of the set is a 12-pole, 450-h-p., 600-rev. per min., 2,080-volt, three-phase, 60-cycle, variable-speed induction-motor, connected on each side to a 20-ton fly-wheel which is 10 ft. in diameter, and to a 6-pole, 170-kw, 575-volt, interpole, direct-current generator. On each side of the shaft is placed a separate exciter, which delivers current at 125 volts. The lubrication of the four main bearings that support the fly-wheels * Presented also, by mutual agreement, at the meeting of the American Institute of Electrical Engineers, New York, N. Y., Mar. 11, 1910. Engineering and Mining Journal, vol. lxxxviii., No. 3, p. 110 (July 17, 1909).

Sep 1, 1910

By B. M. Larsen

NEVER having actually tried to engage in the systematic education of anyone, and having little direct knowledge of the practical problems and limitations in the field of education, I can pose only as a "nonexpert" in this field, one whose ideas are to be regarded as personal opinions. The necessity for compromise between educational ideals and the practical limitations of time, money, and mental capacities of both student and teacher is evident in the preparation of an end product that we may regard with a reasonable degree of conviction as a professional engineer. We need to do so many things. The engineering student must have a clear understanding of the basic sciences; he should develop manual skills and co-ordination; he should speak and write the language with simple clarity and directness; he should gather knowledge of a special field; and, he should be educated for living in a broad ..

Jan 1, 1948

By W. S. Ayres

I. INTRODUCTION. THIS cavern was discovered Oct. 22, 1904, by Mr. Charles H. Deutschman, in company with whom I made, May 29 to June 3, 1905, at the request of Mr. Howard Douglas, Superintendent of the Canadian National Parks, the first exploration of it for the Canadian government. The results were stated in a paper, orally presented, with lantern-views from my photographs, at the British Columbia Meeting of the Institute, Victoria,, B. C., July 5, 1905.* The present paper embodies also the results of a second examination, made Oct. 25 to 29, 1905. The accompanying map, Fig. 1, will serve as a guide to the following description. II. LOCATION. The cavern is situated at snow-line, at the head-waters of Cougar creek, on the west slopes of the Selkirks, about 2 miles north from Ross Peak water-tank, and 5.5 miles west from Glacier House, on the main line of the Canadian Pacific Railway. It was then reached by an arduous climb from the water-tank, up the ravine of Cougar creek, for 8,000 ft. (2,000 ft. of altitude) over rock- and snow-slides, and through a thick tangle of alders. But an easy and very picturesque trail has, during the past summer, been opened by the government from Glacier House. Figs. 2, 3 and 4 represent views, not heretofore published, of the grand scenery of this region, so rapidly becoming the-object of attraction to thousands of tourists from all parts of the world. These views, as well as those shown in. Figs. 5, 6, 7, 8

Jan 1, 1907