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By W. H. Bassett

A 10-year, sea-water, corrosion test of tubes of several copper alloys has shown that many alloys withstood attack by solution, pitting, and dezinkification; a 1-year, salt-spray test of sheet-metal specimens of the same composition showed the same results. THE late J. P. Sparrow, chief operating engineer of the New York Edison Co., carried out a series of practical tests on condenser tubes of several copper alloys and reported on the results to the Association of Edison Illuminating Companies at its meeting in' September, 1913. In the preparation of these tubes the senior author had the pleasure of cooperating. Copper-zinc alloys in the proportions of 60-40, 70-30, 80-20, 90-10, and Admiralty metal, which is in effect 70-30 with 1 per cent. of tin, were tried. Monel metal and several copper-nickel alloys, and 8, 5, and 3 per cent. aluminum bronze were also tried. At the time of this report, the aluminum bronze had been in service for 4 1/2 years and seemed to be giving especially good results but later it began to fail and showed no substantial improvement over Admiralty metal. Monel metal was unsatisfactory and the nickel alloys apparently did not give better service than the Admiralty alloy. Previous to the publication of the report, and after considerable discussion, it was agreed that a test where tubes of different kinds could be under laboratory observation would be advisable, so the apparatus described here was set up in The American Brass Co.'s Waterbury Laboratory. This was fitted with tubes of copper, brass, bronze, nickel silver, cupro-nickel and other alloys, and the test started Oct. 11, 1912. Salt water from East River, New York harbor, was barrelled and transported to the laboratory for the test. A fresh supply, completely replacing the water in service, was obtained at the end of each six months period.

Jan 1, 1925

By W. E. Bawden

Situation: Creighton mine, situated about twelve miles west of Sudbury, Ont., on the Algoma Eastern railway, is owned and operated by the International Nickel Company, incorporated in the United States under the laws of New Jersey. The ore is smelted at Copper Cliff, near Sudbury, and the matte is refined at Port Colborne, Ont., on lake Erie. Geology: The ore occurs in what is known locally as 'the basin' near Sudbury (Figure 1) the central part of which is composed of the Animikie series of sediments, consisting of sandstones, slates, tuffs and conglomerates. The basin is about 16 miles wide and 36 miles long. The Animikie sediments are surrounded by a sill of norite - a gabbro rock in which the pyroxenes are orthorombic. On the outer contact of this norite the sulphide deposits occur and the Creighton deposit, similar to others, lies on the southern edge of this basin. There are two orebodies at the Creighton, the upper one called the footwall orebôdy, and the lower one the hanging-wall orebody. The hanging-wall of both of these bodies is norite, and the footwall of the upper one is granite. The two are separated by an intrusion of greenstone which forms the footwall of the lower body. The ? maximum length of the deposit is 1000 feet and the maximum width is approximately 300 feet. It narrows at the ends and is somewhat lenticular in shape. The dip is about 45 o to the west, and the strike is north and south. The orè is a mixture of three minerals - pyrrhotite, chalcopyrite and pentlandite. The pentlandite, which is distinguished by its cleavage from the other two, is apparent to the naked eye only in the lower orebody and is more finely disseminated in the upper one. The lower body contains a little higher percentage of nickel.

Jan 1, 1925

By R. V. Wheeler, F. V. Tideswell

Coal being essentially a complex conglomerate of plant remains that have undergone decay and interaction in varying degree, it is understandable that attack on the problem of its chemical constitution by normal chemical methods should have been attended by but slight success. The obvious method of fractionation by means of selective solvents has yielded a few results of some value. Thus it is known that from many, if not all, bituminous coals organic solvents extract small percentages of oxygenated compounds, which are generally assumed to have been derived from the original plant resins, though a more probable source would appear to be the glycerides and waxes of the plants. Organic solvents also extract small proportions of hydrocarbons, the origin of which is doubtfill. Of more importance is the action of such pseudo solvents as pyridine, which, in addition to their specific solvent action, have the power of resolving and simplifying a portion of the coal substance in a manner analogous to that by which water can disperse a hydrogel. Early work with pyridine indicated that coals are composed of two main classes of compounds: the one soluble in organic solvents, the other capable of being partly dispersed in pyridine. Recent work has shown that the dispersion is colloidal in character and that it may be accomplished by the use of solvents less active than pyridine, such as benzene or chloroform, provided that the temperature of extraction is raised or the coal has been suitably preheated. The action of reagents on coal has proved of little value in the past, but some insight into the constitution of coal has been given by regulated destructive distillation. Thus, it has been shown that coals behave on distillation as though composed of two main classes of compounds: the one readily decomposable at moderate temperatures (yielding mainly the paraffins), the other undergoing a preliminary early decomposition (with evolution of oxides of carbon and water) and yielding a residue that at higher temperatures breaks down, yielding much hydrogen.

Jan 1, 1925

FREQUENTLY the Survey Department is caIled upon to estimate the quantity of material in various dumps, dams piles, etc... and in the carrying out of this work various methods may be employed.The method used will vary according to the particular case in hand, and factors such as accessibility of the top of the dump, steepness of its sides, height, and the condition of the material to be estimated. A certain amount of "give and take" must be adopted in the treatment of small local cavities and mounds.In all cases it is desirable that the surveys made should be tied on to the lease surveys for the purpose of location, and that all levels should be reduced to the mine datum. It is also desirable to obtain levels of the original surface before deposition of the material to be estimated. If these have not been obtained beforehand, levels and transfers round the top will be the next best. If space is availabIe, flat surface is chosen as a site for the dump, etc. This is of the utmost importance in those cases where the material will have to be...

Jan 1, 1925

By J. Brian Eby

Contact metamorphism of coals is any physical or chemical change in the character of a coal directly attributable to heat of surface or intrusive igneous rocks. Coal beds so affected are found in the United States, England, Alaska, Mexico, New Zealand, Greenland, and other countries. Particularly in the United States, there is a wide occurrence of contact altered coals; conspicuous examples are found in Colorado, Utah, New Mexico, Illinois, and North Carolina. During a recent examination of coal beds on Yampa River, in northwestern Colorado, the author had an opportunity to make some detailed observations on the contact metamorphism of coals. In this field, coals over an area of 20 sq. mi. have been affected by dikes, sheets, and sills;' samples of the coals were systematically collected and analyzed,2 with the view of obtaining more specific data on the character of these alterations. The investigation was threefold in purpose: to secure information on the lateral effects of a dike cutting a coal bed, on the range in vertical effects on coal beds overlying sheets or sills, and on the range in the vertical effects on coal beds underlying sheets and sills. Favorable field conditions, such as fresh outcrops and newly dug prospects, made possible many of the field observations and collections. The coals studied in this field belong chiefly to the Mesaverde and 11Laramie" formations. The Mesaverde coals, on the average, are blocky low-rank bituminous coals; the "Laramie" coals, which are considerably younger, are of subbituminous rank. The coals of both formations, in the northeastern part of the Yampa field, have been greatly affected by basalt intrusives, yielding all variations of carbonized coal from natural coke to the unaffected material. The igneous rock that directly affects the coals is a fine-grained olivine basalt that is intruded, in sheets up to 200 ft. thick, into the coal-bearing

Jan 1, 1925

For the convenience of members who may be traveling from place to place, the Secretary has compiled a list of libraries or other places in the United States and foreign countries where MINING AND METALLURGY or the Transactions may be consulted. This list will be sent to members if they so request.

Jan 1, 1925

For the convenience of members who may be traveling from place to place, the Secretary has compiled a list of libraries or other places in the United States and foreign countries where MINING AND METALLURGY or the Transactions may be consulted. This list will be sent to members if they so request.

Jan 1, 1925

"The Midvale. Plant of the United States Smelting, Refining and Mining Company, situated twelve miles south of Salt Lake City, consists of mills for concentrating lead-zinc ores and a custom lead smelter.The milling department includes a 475-ton gravity mill for ores from the United States Mines at Bingham, a 100-ton Huff electrostatic zinc plant and a 60-ton pilot flotation mill for differential separation of lead and zinc. The gravity mill and electro¬static plant are being replaced by a 600-ton differential flotation plant, now under con¬struction, for differential separation of lead, zinc and iron. This new mill will have cap¬acity for treating custom ores in addition to ores from the company's mines at Bingham.The smelting department is equipped to handle 1600 tons of charge per day through six blast furnaces, 48 inches by 160 inches at the tuyeres. All gases from both blast furnaces and roasters are filtered through baghouses, which remove the dust from the gases so effectively that even when the plant is running at full capacity no smoke can be seen coming out of the 450-foot brick stack handling rca2ter gases, nor out of the two shorter steel stacks which take the blast furnace gases. On this account the Midvale plant has come to be known as the ""smokeless smelter.""The blast furnace gases are filtered through 832 woolen bags, 33 feet 6 inches by 18 inches in diameter, and 1200 woolen bags, 28 feet by 12 inches in diameter."

Jan 1, 1925

A shrinkage stope is an overhand stope in which the broken ore accumulates until the stope is completed to, or near, the level above. As broken ore generally occupies at least 60 per cent. more space than ore in place, about a third of this must be drawn out as the stope advances to leave a working space under the back. The ore remaining supports the miners and gives temporary support to walls, and is all withdrawn when the stope is finished. The shrinkage-stope method is applicable to steep-dipping deposits of strong ore with strong walls. It may be applied to narrow or wide veins, and is simple and cheap. Five examples, which include important and varied types of deposits, are given: namely, Kennecott, Homestake, Jarbidge district, Mogollon district, and Cripple Creek district.

Jan 1, 1925

For many years it has been known that large bodies of iron ore existed in Iron and Washington counties in Utah. The ore is chiefly hematite-both hard and soft-though some magnetite is found. No definite and complete estimate of the iron ore reserves of the state have been made. The U. S. Geological Survey estimated that 40,000,000 tons of ore were disclosed by development work averaging only 35 feet below the surface of the ore. The ore is found along an area about one and a half miles wide by twenty miles long, and for the most part on the eastern and southern slopes or foothills of Three Peaks. Granite Mountain and Iron Mountain. Later estimates by others have gone as high as ore in sight 164,000,000 tons, probable ore 300,000,000 tons and possible ore 1,000,000,000 tons. Whether this last estimate is too great or not there is sufficient iron ore in Utah to justify the starting of an iron industry. Two companies are now mining iron ore in Utah, the Columbia Steel Corporation and the Utah Iron Corporation. The mine of the Columbia Steel Corporation is at Iron Springs a few miles west of Cedar City. About 650 tons, of ore a day is being shipped to the blast furnace at Ironton. The ore is mined by the glory hole method. After being drilled it is blasted to the bottom of the several glory holes and is dropped through chutes into cars on the ore haulage level below. It is then hauled by electric locomotives to the crushing plant, where it is crushed to blast furnace size before going to storage bins. Some of the softer ore is brought to the chutes by Fresno scrapers.

Jan 1, 1925

By Ludwig Schmidt

Investigations conducted by the Bureau of Dines pertaining to the reduction of evaporation losses of petroleum have shown that such losses may be reduced 70 to 80 per cent by the use of vapor-tight tanks equipped with vacuum and pressure relief valves, and vapor-tight thief hitches. Additional studies have shown that it is often economical to supplement this type of construction with other measures that will reduce evaporation losses still further. Water-cooling systems, insulation, and light colored paints are the measures most often used in connection with vapor-tight tanks. Painting with light colored paints probably is employed in the greater number of cases. On account of the cost of insulation, or of installing water cooling systems, the use of these methods are restricted to tanks containing gasoline or crude petroleum with a very large content of low-boiling fractions. The effect of cooling systems has been discussed in a previous report.2 In choosing paints for tanks many factors must be considered. Probably the three most important are cost, protective value, and color. Many companies have adopted a standard color for all of their tanks in this way they reduce the initial cost of paint by buying in large quantities. The tank farms of such companies usually have a neat appearance, resulting from the uniform painting of all tanks. This procedure also has advertising value. Unfortunately, most of the paints used to protect steel are of the darker colors, usually red or black. These colors accelerate the rate of evaporation. Several companies have solved this difficulty by using a dark colored metal-protective paint as a primer coat, and a paint of any desired color for the final coat. Special metal-protective primers to be used under light-colored cover coats have been placed on the market by several paint manufacturing companies.

Jan 1, 1925

"NAME…""Utah"" is derived from the name of the Indian tribe, variously spelled ""Yuta, “Ute"" ""Youta,"" ""Uta,"" ""Eutaw,"" and finally ""Utah."" It means ""in the tops of the mountains,"" or ""on the heights."" The state emblem is the ""Beehive,"" typical of industry. State nickname is ""Beehive State.""AREA…Utah is the tenth state in area. It contains 84,990 square miles, of which 2,806 miles are water. When admitted as a territory in 1850, Utah included all the area from the east line of California to the summit of the Rocky Mountains between the 37th and 42nd parallels, which embraced practically all of the present state of Nevada, all of western Colorado, part of Idaho and part of Wyoming, in addition to the present area of Utah.TOPOGRAPHY…Utah is generally mountainous, with several main ranges and also detached groups of mountains. The valleys are broad and level. The mean altitude of the state is 6,100 feet above sea level, which makes the state the third highest of the Union. The highest point in Utah is King's Peak (13,498) in the Uinta range. The lowest point is Beaverdam Creek (2,000) in Washington county.CLIMATE…The climate is diversified between mild temperate in the northern portion to semitropical in the southern portion. There are four distinct seasons. Snowfall is heavy at the greater altitudes and rare in the southern portion. Rainfall is moderate throughout the state. Extremes of heat and cold are unusual."

Jan 1, 1925

By John T. Norton, Robert J. Anderson

The purpose of this paper is to report evidence, regarding metal structures, that is contradictory to the amorphous-metal hypothesis of Beilby, and particularly evidence that is opposed to the proposition that a vitreous amorphous layer is produced by polishing a piece of metal. According to the theory of Beilby, which has been developed by Rosenhain and others, polishing a piece of metal greatly affects the condition of the metal at or near the surface polished, making that surface entirely different in character from the metal beneath. A vitreous amorphous surface film is said to be formed. The polishing process, on the basis of Beilby's explanation, is well known and does not require discussion here, but it is advisable to seek the precise meaning of the term "amorphous." According to Beilby, "amorphous means non-crystalline in the most intimate sense of the word; the molecules arc not marshalled in crystalline order and orientation." According to Rosenhain, the amorphous condition is that assumed by a metal when the crystalline arrangement is completely broken up so that the atoms exist in a state of disorderly arrangement similar to that which exists in the liquid state. Thus, from the point of view of the phase rule, the "amorphous phase" is regarded as being identical with the liquid phase. Amorphous metal is often likened to an undercooled liquid. A crystalline substance is one in which the atoms are arranged in space according to some definite repeating geometrical pattern. The existence of amorphous metal has not been definitely proved. The evidence offered here that amorphous metal probably does not exist is of a direct nature and is afforded by x-ray diffraction effects given by a number of metals and alloys when polished, cold-worked, and annealed. Considerable of the experimental work was carried out with substantially pure aluminum and the aluminum alloy duralumin, but many of the observations made on these materials were checked by similar observations on copper, iron, tin, zinc, lead, mild steels, and

Jan 1, 1925

By R. C. Wallace

In the early explorations of the Northwest, the search for minerals played a not inconsiderable part. The first episode had its disillusioning sequel. Sir Martin Frobisher, in 1576, sailed up that bay in Baffin land now known as Frobisher bay, thinking that he had the coast of Asia on his right hand. He brought back from this expedition a piece of 'black earth' from Hall island, from which an alchemist by coaxing nature, or his own conscience, obtained gold. A second expedition of three ships was fitted out in 1577, and a third of fifteen ships in 1578. The ships were loaded with this 'black earth', which on subsequent investigation was found to be worthless, and interest in minerals for the time being ceased. In 1612 Hall and Baffin went in search of a gold mine near the Arctic circle on the west coast of Greenland, reported to be worked by the Danes. They found old workings, but no ore. To come nearer the Hudson Bay area, it is noteworthy that the charter granted by Charles II to the Hudson Bay Company in 1670, as a result of the explorations of Radisson and Groseillers, was given "-in consideration for their having at their own cost and charges undertaken an expedition to Hudson bay in the northeast parts of America, for the discovery of a new passage to the South sea, and for the finding of some trade for furs, minerals and other considerable commodities, and of their already having made by their undertakings such discoveries as did encourage them to proceed farther in pursuance of the said design, by means whereof there might probably arise great advantage to the King and his Kingdom - ".

Jan 1, 1925

The mountains of Utah contain one of the largest deposits of high grade bituminous coal in the world. According to the United States Geological Survey, there are 13,130 square miles of land known to contain workable coal, and these extensive fields contain 196,000,000,000 tons of coal. More remarkable than the extent of the coal fields is the thickness of the coal beds. Over three-fourths of the output of coal in Utah is recovered from beds ranging from 8 to 17 feet in thickness, as com- pared to one-eighth of the output of the entire country from such beds. In 1917, Utah mined one-third of its coal from seams at least 16 feet thick, compared to one-half of one per cent of the total bituminous output of the country from like seams. Coal at Wales, in Sanpete county, and in the vicinity of Coalville, Utah, was, it is reported, the first discovered by white men in the state. Wales claims the distinction of having produced the first coal mined in Utah. Two men, who had been coal miners in Wales, learned of the coal from an old Indian chief who called it "rock that would burn." In 1857, the town of Wales was founded and coal mined, and in 1858 some coke was manufactured and hauled by ox team to Salt Lake City. South of Wales is Castle Valley, in Wasatch Plateau field. From 50 to 60 miles of the old Spanish Trail from Santa Fe. New Mexico, to Monterey, California, lies in Castle Valley. The coal in this field may or may not have been known at the time the trail was used extensively. The first published reference to this coal, however, was made by a party of the Corps of Topographic Engineers in their journal for October 11, 1853.

Jan 1, 1925

By Robert S. Archer, Zay Jeffries

It is about fifteen years since the development in Germany, largely by Alfred Wilm, of the aluminum alloy called duralumin. In this alloy, combining as it does the tensile strength of mild steel with the lightness and corrosion resistance of aluminum, a distinctly new material was presented to the engineering world. Despite the evident usefulness of this material, however, its commercial development has been slow, due in part to the difficulties involved in its fabrication. In view of the potentially great utility of strong aluminum alloys, it seemed desirable to find means of producing such alloys with better fabricating properties, and work was undertaken with this object in the laboratories of the Aluminum Company of America several years ago. This work has resulted in the production of two new types of aluminum alloy of the "strong alloy" class, having distinctly improved fabricating qualities. The knowledge gained has also made it possible to produce alloys of the duralumin type with greater strength and hardness than previously obtained. There have thus been made available some new engineering materials which it is the object of this paper to describe. These alloys, induding duralumin, are fundamentally wrought alloys. Castings of the same compositions heat treated in the same manner give inferior physical properties, particularly as to ductility. The statements made subsequently concerning properties and heat treatment apply to material that has received sufficient working to thoroughly break down the cast structure. The material referred to has, in general, undergone a reduction in section of at least 80 per cent, by mechanical working. It may be mentioned in passing that other compositions have been found that are suitable for the production of the maximum physical properties in heat-treated castings.

Jan 1, 1925

By Carl Zapffe

Because no rock outcrops exist in the Cuyuna district, it is necessary first to make a magnetic survey with a dip needle, or possibly with a sun-dial compass, and determine the area or belt of magnetic variations and the maximum lines of magnetic attraction. A dip-needle survey is quicker to make, is sufficiently accurate, and will suffice. Regardless of how poorly defined the magnetic attractions may be, it is important that they be determined. Even if drilling has developed ore on an adjoining property, the survey should not be omitted. Iron-bearing formation is indicated by the magnetic attractions, but whether or not ore exists must be determined by drilling. The maximum line of magnetic attraction offers the best place to begin drilling. If no magnetic attraction exists, nearby developments are the only guide; and if these also are lacking, drilling is governed by guess. Test-pitting is not employed in exploratory work because the surface is too deep. Tunneling cannot be used because the topography is not suitable. Exploration shafts are a waste of time and expense, because from every standpoint drilling with churn and diamond drills is the most applicable method for exploratory work. Light drilling equipment only is needed. Rarely have heavier drills been required, for seldom do holes exceed 400 ft. in depth, and about 100 ft. of this is in glacial drift which is easy to penetrate. The deepest hole is 1023 ft. Because of the steep inclination of the strata and the narrowness of the orebodies, many angle holes have been drilled, mostly at 60' to 70" from the horizontal and against the dip of the formation. Angle holes are most advisable. If after initial drilling the beds are of shallow dip, vertical holes or holes of any angle can be used. The total cost of drilling a property is much greater if only vertical holes are used because more holes must be drilled to obtain the requisite information than when angle holes are used. Many tests for variation in angularity of a finished hole have seldom shown more than 2'; therefore, such tests may with safety be abandoned. Because the orebodies are generally about 100 ft. wide and cross a 40-acre tract at a slight angle, and as the dips are usually about 70"

Jan 1, 1925

By Thomas Varley

Data on the consumption of reagents used in flotation during the years 1923 and 1924, in metallurgical plants in the Unites States, are presented in this paper. Two previous reports Lave been issued by the Bureau of Mines on consumption of oils and other reagents used to flotation - namely, "Statement of Flotation Oils," by O. C. Ralston, issued in 1913, and Serial No. 2203, "Consumption of Reagents Used in Flotation," by Thomas Varley, for the year 1919, issued in January, 1921.

Jan 1, 1925

By Wm. Monay

MR. MONAY (Vice President Kinney Coal Co., Scofield, Utah): The past year and a half has witnessed a series of coal mine disasters in Utah and Wyoming, concentrated into the short space of a few months, following a long period of years in which the industry was comparatively free from devastating calamities. The natural result has been a hysterical activity on the part of bureaus, commissions and professional reformers who know little about coal mining from a practical standpoint. This activity has been met by the industry in Utah with an attitude of submission, no doubt the result of the fear of being misunderstood by the public. But it is my firm conviction that the lives and property of the coal industry will find their surest guaranty of protection in the humanity, and in the self interest of those operating and working in the mines, rather than in governmental regulation. Inelastic, inflexible blanket statutes and rules will simply stifle and hamper the initiative and progress of our industry in working out its own salvation, under the varying and changing conditions of different localities, different conditions, and in different mines. We who have spent our lives in digging in the mines and operating them, know more about this business than anyone else and I believe it is time for us to speak up and no longer sit meekly by while inexperienced bureaus and unskilled commissions make up laws, rules and regulations for us which when made are on the books to stay, even though in a short time they may prove inapplicable, in whole or in part, or be superseded by something different, and which in some cases create new dangers or lull us into a false sense of security. Shortly after the Castle Gate explosion in March, 1924, a new set of safety rules was issued by the Indus- trial Commission of the State of Utah to become effective July 1st of the same year, the most important of which prohibits the use of black powder in any mine--gaseous or non-gaseous; prohibits the use of open flame lamps in any mine-gaseous or non-gaseous; and requires that rock dusting in all main haulage ways as far as the freezing point and required that all mining machines be equipped with water to be applied while cutting. These rules have been characterized as "Utah's Monument to her Dead Miners" in a large poster spread broadcast over the country from an office in New York that styles itself the Association for Labor Legislation. In reviewing the coal mining history of the State of Utah, in the year 1900, a serious disaster occurred at Winter Quarters. The cause of the same is believed to be an explosion of powder that was stored in the mine, which was a common practice in the early days, and from that time until the Castle Gate disaster, March 8, 1924, a period of some twenty-four years, no explosion of any kind occurred in this district. During all this period open lamps were used, considerable black powder was used, rock dusting was unheard of, sprinkling with water was very generally done-all without any catastrophe. Since the adoption of the new rules, we have 'had a very violent explosion at the Carbon Fuel mine in Spring Canyon. At the time of this explosion, 3,000 feet of the main slope had been rock dusted several times between July 1st and September 21st. The second left entry, which is a main haulage way, a distance of 3,000 feet was completely rock dusted on the date of the explosion. This mine is not considered extremely gaseous, yet an explosion as violent as that of the Castle Gate mine occurred. Some thirty men who had been loading coal in various parts of the mine on this Sun- day, the day of the explosion, and other men employed in rock dusting the second left entry, had just left the mine a little while before it occurred, and no abnormal condition in the mine was noted. At the time of the explosion five machine men were in the mine.

Jan 1, 1925

Utah greets the members of the American Institute of Mining and Metallurgical Engineers on this occasion with the assurance that their presence is gratefully appreciated. The fact that this is the second time the Institute has so honored Utah is viewed by us as an approval of a past achievement and an incentive to a greater one. Our sincere hope is that our guests this year will have experiences so pleasant and profitable that they will be disposed to come yet again-and again. As use is the measure of value, we appraise our hospitality by the extent to which our friends accept it. World changes incomprehensible at that time have taken place since the Institute met here in 1914. The mining industry of Utah undertook to bear its full share of the responsibilities that came with those changes and, we believe, carries its additional burdens with all the resolution and optimism characteristic of American citizenship and especially characteristic of mining men and mining operations.

Jan 1, 1925