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By Eldon C. Pattee

Variations of a very reliable geochemical field test for beryllium developed by Patten and Ward, have been adapted by the U.S. Bureau of Mines to facilitate rapid testing of reconnaissance samples and to aid in rapid examination of known occurrences. Although several qualitative tests for detecting beryllium have been described in the literature,1,2,3, the Patten-Ward4 morin geochemical field method has the advantages of being rapid and being quantitative for minute amounts of beryllium. In addition to the morin field method, Patten, in cooperation with Griffitts, have developed a contact- print method for determining beryllium in hand specimens.5 The semiquantitative method can be used for rapid screening of samples in exploration or reconnaissance work. The use of beads for fusing samples provides a more rapid test, but gives less accurate results than the method developed by Patten and Ward. The semiquantitative method, however, requires less equipment and combines three stock solutions into one reagent for easy application. Estimates of samples in the range from 3 to 1000 ppm varied from about 0.25 to 5 times the actual beryllium content.

Jan 5, 1965

By W. J. Sharwood

(San Francisco Meeting, September, 1915) CUPELLATION is well known to be one of the most effective methods of separating silver and gold from base metals and other impurities, as well as one of the most accurate means for their estimation. In the latter application it consists in absorbing in some porous medium the fused lead. oxide formed by the oxidation of the lead "bath," which carries with it the oxides of other base metals present. It has long been recognized that small amounts of both silver and gold were removed and absorbed together with the base metals, as well as being to some slight extent volatilized, and in work of the highest accuracy a correction is made for the "cupellation loss." Thus. in the assay of bullion this is done by means of "proofs" of like composition, which are manipulated throughout in precisely the same manner as the assay pieces, and are assumed to lose or gain like amounts. In the case of certain very rich ores and commercial products the loss is adjusted by assaying the cupel itself and recovering the precious metal absorbed, but this doubles the labor and does not remedy the loss by volatilization. Arbitrary tables have been drawn up by various authorities with the object of enabling a correction to be applied without the use of a check. These have been of very limited practical use owing to the fact that a number of factors affect the losses sustained. For a fixed amount of precious metal the loss varies with the amount of lead used, with the nature and amount of the impurities, with the porosity of the cupel, with the air supply, and above all with the temperature at which cupellation is carried on. Pure silver loses relatively much more than gold, but the loss in either is diminished by au addition of the other metal. The concentration of precious metal in the litharge increases as the concentration in the lead increases, but little work has been published connecting the two. If all other conditions remain the same the actual total loss increases, but the percentage loss diminishes, with an increase in the weight of precious metal treated.

Jan 8, 1915

By Willard P. Ward

HAVING been engaged during the past year in the manufacture of ferro-manganese in a blast furnace, I have imagined that some further information on this subject might be of interest to that large number of members of the Institute who are engaged in the iron and steel industries. The great question of the economical production of good steel, ingot metal, or homogeneous iron (we scarcely know now what to call it) from good materials, and at reasonable prices, has, thanks to the intelligence and energy of a few American engineers, been successfully solved in this country. Nearly all first-class railroads, and many that would riot rank so high, have adopted the Bessemer rail. Martin boiler-plates are rapidly gaining ground, in competition with

Jan 1, 1877

By James H. Boettcher, W. Durand Eppler

INTRODUCTION In the second quarter of 1979, Rapid Mining Co., Inc. ("Rapid") inquired whether Crocker National Bank ("CNB") would provide $4 million in term loan financing to help ("Dry Creek") acquire the outstanding shares of the Dry Creek Coal Company ("Dry Creek") in West Virginia. Prior to approaching CNB, Rapid had sought financing with the assistance of a financial advisor from a number of commercial banks without success. A summary of the initial terms requested by Rapid is shown in Table 1 compared with the actual terms on which the transaction closed. It is not difficult to note that the two sets of terms differ significantly. This is often the case when financing requests based on the expectations and vision of a mine developer are juxtaposed with more pragmatic requirements of a commercial bank. The "art" and fund of structuring financing plans for mining ventures (highly leveraged acquisitions or grass roots) comes in working with mine developers to arrive at a final financial structure that meets their objectives and constraints as well as those of the bank or other financial institutions providing much of the financing. Beginning with the terms requested by Rapid and ending with the terms that closed the transaction, this article briefly describes the process we went through with Rapid Mining. The Seller and Buyer The Dry Creek Coal Company was established in 1961, after its owner acquired the coal leases from Republic Steel. Republic has mined the primary coal seam from 1948-1961. Dry Creek was owned as a subchapter S corporation (i.e., for federal income tax purposes, income is taxed at the shareholder level) and had been run on a low key basis. Since the company had virtually no debt and limited cash needs, the owner produced primarily when rail cars were available and income was required. Output was therefore erratic as is shown in the top of Table II, but the result was a profitable little company with an attractive free cash position. Because the owner wished to retire and enjoy his wealth in a more readily spendable form, he had put the mine, with stated recoverable reserves of approximately 13 million tons, up for sale. In contrast, Rapid Coal's investors consisted of a number of investors of disparate financial situations. They had agreed upon a primary objective of income maximization and planned an annual production rate of 120,000 TPA which they and the current owner believed realizable. The Formulation of a Financing Structure Figure 1 presents a simplified overview of the sequence of steps taken in the financing process which lasted approximately three months from start to finish. Since banks see many requests for funding and considerble time is required to follow up on each, an important step was determining, after a brief review of the materials provided to us, whether the basic "eonomic entity" was viable. In this case, the size and quality of the reserves, the inherent operating cost characteristics, the sales arrangements, the management/labor situation and Rapid's principles all appeared to be sound enough to warrant investing the time necessary to do a thorough analysis of the project. Once this decision was made, the evaluation and analytic process shown in Figure 2 was initiated. The first and most fundamental concern of any banker is whether the loan will be paid back as scheduled from the cash flow generated by the project. The amount of debt relative to the owner's equity is of course crucial in such a determination. Before the debt/equity issue was addressed, however, a number of more qualitative factors had to be studied and if

Jan 1, 1985

THE developments in construction and operation of the basic open-hearth furnace that have taken place in recent years have placed new emphasis on the vital influence played by regulation and control of the combustion system in both furnace production and furnace life. The several factors influencing flame development, such as regulation of fuel supply, air supply, air preheat, furnace draft, and furnace reversal, must be controlled closely if successful furnace performance is to be accomplished. Rugged instrumentation of distinctive design is required to supply dependable information concerning operating conditions, which is requisite to proper regulation of combustion. This chapter attempts to give a practical discussion of the various features of open-hearth practice and instrumentation related to the efficient heating of the furnace, control of temperature, and protection of the furnace structure from accidental overheating. The appended references will be helpful to readers wanting a more detailed treatment of individual topics. OPEN-HEARTH FUELS The most important open-hearth fuels are listed in Table 4-1 together with their compositions and other data useful for combustion calculations. A detailed discussion of open-hearth fuels is not attempted here, but certain factors peculiar to their application to this type of process are briefly indicated on the following pages. Very often an open-hearth shop is forced by economic factors to use a fuel to which its furnaces are not very well adapted, because the general fuel-allocation scheme for the works as a whole seems to demand it. Often a variable marginal supply of coke-oven gas or tar must be consumed by the open hearth, together with another fuel such as producer gas, natural gas, or oil, to fill out total requirements. Most furnaces employ more than one kind of fuel during their usefu1 life; however, the partial redesign

Jan 1, 1951

By S. A., Taylor

IT is very difficult to arrive at exact figures for the cost of maintaining excess capacity of coal mines, but we can approximate the various items. To do this, I will take the Pittsburgh district of Pennsylvania and the other districts can be compared to this one. I believe we can take the depreciation item of plant ac- count as a whole and discount it over a period of 20 years; while this is high for some items it is low for others and I believe it is not far from a safe basis. This equals 5 per cent per year, and this depreciation will take place about as rapidly when not in use as when in operation. A fair value in the Pittsburgh district to- day for plant and houses is close to $4 per ton per annum. At 5 per cent this will equal 20 cents per ton per year. The item of keeping the mine in condition, free from water, etc., will be close to an average of 2y2 cents per ton per annum.

Jan 1, 1928

THE developments in construction and operation of the basic open-hearth furnace that have taken place in recent years have placed new emphasis on the vital influence played by regulation and control of the combustion system in both furnace production and furnace life. The several factors influencing flame development, such as regulation of fuel supply, air supply, air preheat, furnace draft, and furnace reversal, must be controlled closely if successful furnace performance is to be accomplished. Rugged instrumentation of distinctive design is required to sup- ply dependable information concerning operating conditions, which is requisite to proper regulation of combustion. This chapter attempts to give a practical discussion of the various features of open-hearth practice and instrumentation related to the efficient heating of the furnace, control of temperature, and protection of the furnace structure from accidental overheating. The appended references will be helpful to readers wanting a more detailed treatment of individual topics. OPEN-HEARTH FUELS The most important open-hearth fuels are listed in Table 4-1 together with their compositions and other data useful for combustion calculations. A detailed discussion of open-hearth fuels is not attempted here, but certain factors peculiar to their application to this type of process are briefly indicated on the following pages. Very often an open-hearth shop is forced by economic factors to use a fuel to which its furnaces are not very well adapted, because the general fuel-allocation scheme for the works as a whole seems to demand it. Often a variable marginal supply of coke-oven gas or tar must be consumed by the open hearth, together with another fuel such as producer gas, natural gas, or oil, to fill out total requirements. Most furnaces employ more than one kind of fuel during their useful life; however, the partial redesign

Jan 1, 1964

By P. Gianella Vincent

Barite deposits are of widespread occurrence in Nevada but there are few pro-ducing properties; most of the latter are in northern Nevada. The production of the state is small at present-in the neighborhood of 15,000 tons annually-but is steadily increasing. The barite occurs in veins and also as replacement deposits in lime-stone. The bulk of the production has come from the replacement deposits. It is thought that the barite was deposited from rising hot waters similar to-and probably contemporaneous with-those responsible for some of the metallic ores of the state. This paper discusses only the deposits in northern Nevada. THE commercial mining of barite did not begin in Nevada until 1916 but although the production has been small there has been a rapid increase in tonnage during the past several years. Barite is widely distributed in the state and production comes from at least nine of the seventeen counties. Apparently this is not generally known, as only two counties are mentioned in a recent publications dealing with barite. The increase in output is due largely to recently discovered barite deposits in northern Nevada. The principal production has come from the northern portions of Lander and Eureka counties; smaller amounts from Elko County. The discussion in this paper is confined largely to the deposits in these counties. Most of the producing area is tributary to the Western Pacific and Southern Pacific Railroads, whose tracks lie along the Humboldt River. Barite is known from other northern counties but so far the production has been small. The output has come entirely from veins and replacement deposits, the latter largely in sedimentary rocks. In general, the barite from veins is white; that from the replacement deposits usually is dark gray to black, although some is light gray or white. Most of the veins contain sulphides and many barite-bearing veins have been worked for their content of base or precious metals.

Jan 1, 1940

By Willard P. Ward

Having been engaged during the past year in the manufacture of ferro-manganese in a blast furnace, I have imagined that some further information on this subject might be of interest to that large number of members of the Institute who are engaged in the iron and steel industries. The great question of the economical production of good steel, ingot metal, or homogeneous iron (we scarcely know now what to call it) from good materials, and at reasonable prices, has, thanks to the intelligence and energy of a few American engineers, been successfully solved in this country. Nearly all first-class railroads, and many that would not rank so high, have adopted the Bessemer rail. Martin boiler-plates are rapidly gaining ground, in competition with

By R. W. Bond

The gas-lift is a comparatively recent development in the Oklahoma and Kansas fields. It was used to some extent in the old Dilworth field several years ago, but the first extensive installations were made in the Tonkawa and Garber fields in Oklahoma early in the year 1926. Compressor Equipment During the early development of the system, the equipment used generally consisted of small tandem compressors of about 250 cu. ft. per min. displacement, driven by automotive-type gas engines, using a short belt drive. These compressors were first installed at the individual wells largely as an experiment. After the experimental installations had proved the method a success, it was considered economically advisable to centralize the compressor equipment in strategically located stations. However, as the information in regard to "gas-lift flowing life" was anything but definite, and the most optimistic estimates in regard to it did not exceed six months, portability of equipment was still the first consideration in the minds of many operators, who continued to install srnall semi-portable com-pressors in their centralized stations. As electric power became available in the fields, the electric motor came rapidly into use as the prime mover for the small compressors. The operating cost of this motor is greater than that of the automotive-type gas engine for the same power output, but the greater continuity of service tends to balance the extra cost. Aside from the semi-portable units, a number of strictly portable compressors were used. These consisted of automotive-type gas engines direct connected to vertical compressors. The unit was assembled on one base and could be mounted on wheels or skids as desired. The chief objection to these, in the writer's opinion, was their small capacity— approximately 150 cu, ft. per min.—which made it necessary to use two, three, and sometimes more units per well, thus making the installation rather costly. However, they have been found valuable for test purposes and emergencies, where installation time is an important factor.

Jan 1, 1928

By S. F. Shaw

The Seminole field was first drilled in 1913. During the next 10 years other attempts were made to discover oil in this field, but without encouragement until March, 1926, when the Indian Territory Illuminating Oil Co. completed NO. 1 Dyer in the Hunton lime for 1100 bbl. On July 16, 1926, the Independent-Garland interests discovered oil in the Wilcox formation when No. 1 T. Fixico came in at 4055 ft. and on Sept. 9, 1926, production reached a peak of 8040 bbl. On Aug. 1, 1927, the daily production of the pools making up the Seminole district amounted to slightly over 500,000 bbl., practically all of which was coming from the Wilcox formation. The Hunton formation has not been very productive of oil, but has maintained a fairly high gas pressure; this formation has been encountered at from 3800 to 4200 ft., below which there is about 100 ft. of Sylvan shale. The shale is underlain by 75 ft. of Viola limestone in a few places in which formation oil has been encountered. Below the Viola lies the upper Simpson formation in which is found the Wilcox sand. The depth of the Wilcox in the Seminole field varies from 3900 to 4500 ft., and initial production has reached as much as 12,000 bbl. The gravity of the oil is about 41° Be. The general practice is to set 6 5/8 -in. casing above the Wilcox and drill in, though in several cases 5 3/16-in. casing has been set for the oil string, and in a few instances, casing as small as 4 3/4 in. has been employed. Production Statistics Production for the Seminole district for the various months since its discovery is shown in Table 1.

Jan 1, 1928

By William Catron

BECAUSE the rich La Colorada orebody of the Cananea Consolidated Copper Co. does not outcrop at surface, after its discovery (by churn drill) and before mining was begun, a large amount of development work was done to learn the shape and extent of the ore and to provide for eco-nomic and effective mining. As these openings progressed, the actual shape of the orebody became known and with this knowledge came the realization that mining this rich and unusual deposit without loss of ore or danger to workmen presented several difficult problems. This paper will describe one of these problems; namely, the handling of an inverted cone-shaped core of barren rock, on the periphery of and below which the ore occurred. It was clear that as the ore was mined out from around and under this inverted cone of rock, weighing about 3,000,000 tons, it would hang over the workings, held suspended only by its own tensile strength and threatening to crash into the stopes below with disastrous results to men and mine. The method of mining developed during the years 1928, 1929 and 1930 anticipated and provided for the eventual collapse of this core of rock. In November 1936 the core settled clown gradually on the edges of the stopes, descending a total of about 50 ft. vertically. The men in the stopes had ample to warning and no lives were endangered. There were no air blasts in the mine. The core broke loose from its top support at the 500-ft. level along old fracture planes and evidently is crushed to the ninth level. Movement was of short duration; the following shift went to work in the stopes as usual. No ore was lost.

Jan 1, 1938

By F. L. Ransome

The following paper aims to present in a much condensed form the salient results of a detailed geological study of the Bisbee quadrangle, Arizona, carried on during the latter part of the year 1902. It is essentially an abstract of the final official report which will shortly appear in the series of professional papers of the U. S. Geological Survey, accompanied by maps, sections and illustrations. I. Geography. The Bisbee quadrangle, which includes the Warren mining district, lies in Cochise county in the southeastern part of Arizona. It is inclosed between the meridians 109" 45' and 110" 00' and the parallels 31" 30' and 31" 201, the latter being locally the Mexican boundarg line. The area of the quadrangle is about 170 square miles, and includes the southeastern half of the Mule Mountains, one of the smaller of the isolated ranges characteristic of this part of Arizona. The Mule Mountains, while less markedly linear than the Dragoon, Huachuca, Chiricahua, and other neighboring ranges, have a general NW-SE. trend. They may be considered as extending from the old mining town of Tombstone to the Mexican border, a distance of about 30 miles. On the northwest they are separated by the broad, flat floor of Sulphur Spring Valley from the Chiricahua Range, and on the southeast by the similar broad valley of the Rio San Pedro from the Huachuca Range. The maximum width of the range is about 12 miles, and its greatest elevation attained by Mt. Ballard, west of Bisbee, is 7,400 ft. above sea-level. An index-map, showing the geographical position of the Bisbee quadrangle, is shown in Fig. 1. The town of Bisbee (Fig. 2), with an estimated population of 6,000, is crowded into a few narrow confluent ravines near the

Jan 1, 1904

By JOHN R. SUMAN

TONIGHT I want to speak of the current problems and the postwar difficulties facing American industry. American industry has done an outstanding job in adjusting its operations to wartime necessity. The national income for 1942 was nearly $120,000,090,000 and of this outlay approximately $55,000,000,000 went for war material. The enormity of the expenditures for war material is indicated by the fact that the expenditures for war purposes alone were greater than the annual gross national income in the period 1931-34. This tremendous production job in turning out a record output of war products was accomplished by industry in spite of a large number of restraining and hampering influences, and I want to mention several of the more important problems.

Jan 1, 1943

By F. C. Langenberg, J. Chipman

New data on the distribution of silicon between slag and carbon-saturated iron at 1600oand 1700oC are presented which, in combination with previously published data, permit the determination of silica activities over a broad range of compositions in the CaO-Al2O3-SiO2 system. The distribution of silicon between graphite-saturated Fe-Si-C alloys and blast furnace-type slags in equilibrium with CO has been described in previous publications.1"3 In this past work the silica-silicon relation was established at temperatures of 1425" to 1700°C for slags containing up to 20 pct Al2O3. This paper presents the results of additional studies at 1600" and 1700° C which extend the silicon distribution data at these temperatures for CaO-A1203-SiO2 slags over a range from zero pct A12O3 to saturation with A12O3, or CaO.2A12O3. The upper limit of SiO, is set by the occurrence of Sic as a stable phase when the metal contains 23.0 or 23.7 pct Si at 1600" or 1700°C, respectively. The activity of silica over the expanded range is determined directly from the distribution data.3 Recently, 4-7 other investigators have studied the activities of SiO, and CaO, principally in the binary system, using different methods and obtaining somewhat different results. EXPERIMENTAL STUDY The experimental apparatus and procedure have been fully described in previous publications.1, 3 Six new series of experimental heats have been made, four at 1600° and two at 1700°C. Master slags of several fixed CaO/A12O3 ratios were pre-melted in graphite crucibles, and these were used with additions of silica to prepare the initial slag for each experiment. Slag and metal were stirred at 100 rpm and CO was passed through the furnace at 150 cc per min. The initial sample was taken 1 hr after addition of slag at 1600°C or 1/2 hr after addition at 1700°C. The run was normally continued for 8 hr at 1600°C or 7 hr at 1700°C, and the final sample was taken at the end of this period. Changes in Si and SiO2 content indicate the direction of approach to equilibrium, and in a series of runs where the approach is from both sides this permits approximate location of the equilibrium line. Fig. 1 shows the results of such a series of 15 runs at 1600°C for slags of CaO/Al2O3 = 1.50 by weight. Figs. 2 and 3 record other series at 1600°C and Fig. 5 a series at 1700°C with fixed CaO/Al2O3 ratios. The results of the experiments at 162003°C have been reported in part in a preliminary note.3 In the experiments recorded in Figs. 4 and 6, the slags were saturated with A12O3 (or with CaO.2A12O3 within its field of stability) by suspending a pure alumina tube in the melt during the course of the run. The final slag analyses were used to establish the liquidus boundaries8 in the stability fields of CaO.2Al,O3 and of A120,. ACTIVITY OF SILICA The free-energy change in the reaction has been calculated by Fulton and chipman2 from recent and trustworthy data including heats of formation, entropies, and heat capacities. The more recent determination by Olette of the high-temperature enthalpy of liquid silicon is in satisfactory agreement with the values used and therefore requires no revision of the result which is expressed in the equation: SiO, (crist) + 2C (graph) = Si + 2CO(g.) [1] &F° = + 161,500 - 87.4T The standard state for silica is taken as pure cristobalite and that of Si as the pure liquid metal. Since the melts were made under 1 atm of CO and were graphite-saturated, the equilibrium constant for Eq. [I] reduces to K1 = asi /asio2 The value of this constant is 1.77 at 1600°C and 16.2 at 1700°C. Through K1, the activity of silica in the slag is directly related to the activity of silicon in the equilibrium metal.

Jan 1, 1960

Jan 1, 1961

Discussion of the paper of WALTHER MATHESIUS, presented at the New York meeting, February, 1915, and printed in Bulletin No. 99, March, 1915, pp. 539 to 555. JOSEPH W. RICHARDS, So. Bethlehem, Pa.-This paper answers. partly the difficult questions which have come up as to why it is not economical to use higher blast temperatures in the smelting of Mesaba ores, such as the high temperatures used in European practices, and the answer is very plain that the ores will not stand the higher temperature. But the paper does not go into detail as to what special difficulties were found with the higher temperature of blast, and I would ask the author to kindly specify them. W. A. FORBES, New York, N. Y.-A large part of the troubles that furnace men experienced in using high-blast heats in smelting Mesaba ores in the early days of using Mesaba ores, was clue to the attempt to use these soft ores on furnaces having the same lines as the furnaces used in smelting the hard Old Range ores. As the result of observation and study, the dimensions of the lower part of the blast furnaces have been changed and the difficulties of the blast-furnace men in operating with a large percentage of Mesaba ore and high-blast temperatures have been largely overcome. The changes I refer to in particular are: (1) steepening the angle of the bosh; (2), decreasing the height of the bosh; (3) increasing the diameter of the hearth. JOSEPH W. RICHARDS.-Mr. Forbes's answer is quite satisfactory, and the moral which it points is that when the furnace is run with a higher temperature in the smelting zone, the furnace lines which were adapted for the lower temperatures are not necessarily those best suited for the higher hearth temperatures. If. enriched blast were used in a furnace, and higher temperatures run, it would be found necessary to further modify the lines of the furnace to meet the new conditions and to get the maximum output with economy. J. E. JOHNSON, JR., New York, N. Y.-It seems to me this is one of the few papers which could well have been a little longer. The data which Mr. Mathesius has given us, I think should be considered in connection with the paper which Mr. Brassert read before the American Iron and Steel Institute last spring, in which he described how they had obtained remarkable results with furnaces with steep but very short boshes; the angles have been raised to 80°, and the boshes made so short that they no longer appear as a conspicuous part of the shape of the furnace.

Jan 5, 1915

By M. G. Jones

AT the Edwards mine a 4 by 81/2-ft two-compartment shaft is used for men and supplies in the older workings down to the 900-ft level. All ore is hoisted through a 5 by 15-ft three-compartment vertical shaft which extends to the 1500-ft level. Ore pockets are on the 1300- and 1500-ft levels. The two-compartment countershaft used below the latter level is 6 by 12 ft inclined at 42°. Ore from the countershaft is hoisted to the 1350-ft level where it flows by gravity to the 1500-ft level ore pocket. One-ton skips are used in balance in the countershaft and two-ton skips, also in balance, from the 1500-It level to the surface. These skips are slung under the man cages. Each level has an ore pocket of 200 tons' capacity. Development at Edwards is similar to that at Balmat except that haulage drifts are only 7 by 7 ft. They are mucked with Eimco-Finlay No. 12 loaders. A drill carriage similar to that used at Balmat is being tried out on the new 2300-ft level, the present bottom of the mine. Drifts are driven below grade and later raised 6 in. and ballasted with waste leaving a ditch 6 by 12 in. at one side for drainage. All development is done on an incentive bonus system, the miner paying for his explosives.

Jan 1, 1947

By Benjamin C. Greene, H. Beecher Charmbury

Water is a most remarkable substance, essential for life of all kinds. As well as needing water to survive, man has always used it for agriculture, transportation, recreation, and many other things. When our country was young and inhabited by few people, the streams, rivers, and lakes were able to provide all the clean water needed by man and take away all the wastes created. However, with our growing population and an ever-increasing demand for goods and services, the public, industry, and government at all levels have become acutely aware of the need to manage the nation's water resources more efficiently. Abundant energy from many sources has helped this nation to become the greatest industrial nation in the world. Coal has contributed a major portion of this energy, generating electricity, running railroads, and maintaining national security during wartime. The result has been the highest standard of living in the world and a time of widespread economic prosperity. The use of water in coal mining is somewhat different from its use in most industries. With the exception of water used in cleaning plants, for underground dust control, and for fire protection, most of the water en- countered in coal mining operations serves no useful purpose. In other words, it is an undesirable element and must be removed, otherwise it will interfere with operations, cause potential water quality problems, and may even stop operations by flooding. In the past, removing water from working areas of most mines was usually a fairly simple matter. Pumps with piping were installed at sumps or low spots in the mine and the water was pumped to the surface or to drainage control facilities constructed for the operation. Ditches were often used to collect and drain the water by gravity to the outside or to main sumps for pump discharge. In either case, the water was allowed to flow into the nearest stream or river. The concept of "water is water" was generally accepted without too much concern for what was in

Jan 1, 1981

By T. E. Schwarz

The publication of the report by Mr. F. L. Ransome1 was welcomed by many engineers who had mined in the heart of the San Juan country, braved its long and snowy winters, climbed its lofty peaks, run the gauntlet of its snow-slides, and studied its problems of geology, while making dividends for their English or American clients. This report helps one to understand why the bonanzas occurred, and why the inevitable " borrasca " presents itself where least expected. The Red Mountain district of Ouray county, a very productive section from 1884 to 1893, occupies considerable space in the report mentioned. The character of the ore-occurrence.

Jan 1, 1906