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HOW the Engineers' Memorial clock and carillon at Louvain has impressed the people of that city is indicated by the following letter sent by the Secretary of the University of Louvain to the Secretary of the United Engineering Society. We are still full of the memories of that splendid July 4, when we came into such .delightful contact with our American friends and more specially with the representation of the engineering societies of the United States. It was a great joy for all the members of the University to see those, American friends who have given to us such a splendid memorial in honor of- the brave men who fell in the Great War.

Jan 1, 1928

US 4,185,078-In the recovery of rhenium values from an aqueous sodium molybdate solution contained in the hydrometallurgical processing of roasted molybdenite, improved results are realized by using a described extractant consisting of a quaternary ammonium compound and benzene or other highly aromatic solvent which dissolves a quaternary ammonium-rhenium complex Essentially all rhenium is recovered from the solution and the extractant can be regenerated and recycled. This patent is a continuation-in-part of US Patent No. 4,049,771, dated Sept. 20, 1977. L R. Quatrini and M.B MacInnis, assigned to GTE Sylvania Inc. Jan 22, 1980. 6 pp (423-49). Flied. 7-19-78 (926,167).

Jan 1, 1982

By Gerhard Derge, Harold Markus

The introductory paper1 of this series described the potential behavior of tin in sodium carbonate and bicarbonate solutions whose pH ranged from 8.4 to 11.2 and demonstrated that significant and reproducible results could be obtained by proper attention to experimental technique. In examining the corrosion of tin under such conditions, it is desirable to know the effects of anions, aside from carbonate, that are likely to be present in commercial materials packaged in tin. Therefore, in this paper the potential behavior of tin in carbonate solutions to which sodium fluoride, chloride, bromide, iodide, sulphate, nitrate, monobasic phos-phate, dichromate, perborate and acetate have been added will be dcscribed. For most of the additions, solutions containing 0.001 and 0.01 moles of the added material were studied. The experimental procedure was exactly the same as that described in the first paper; the pH of the electrolyte was controlled by adjusting the ratio of carbonate to bicar-l,ol~ate as follows: pH 0.1 M NaHC0............................................ 8.4 2 parts 0.1 M XaHCOr, 1 pa.rt 0.1 M NaZCO?................. 9.5 1 part 0.1 M NaHCOs, 2 parts 0.1 M iVa.,C03. ................ 10.0 0.1 M Na2C0............................................. 11.2 The reagents used were all of C.P. grade. The anions studied may be divided into three groups: (1) anions that had little or no effect upon the potential curves—sulphnte, nitrate, and acetate; (2) those that helped to prevent corrosion at low pH only -fuoridc, chloride, bromide, and iodide; (3) those that helped to prevent corrosion at high pH also—phosphate, pcrborate, and chromate. Potential Measurements f The time-potential curves represntative of group 1 are shown in Fig. 1. These are the curves for 0.005 M sulphate ion and their similarity

Jan 1, 1939

By Harold Markus, Gerhard Derge

The introductory paper1 of this series described the potential behavior of tin in sodium carbonate and bicarbonate solutions whose pH ranged from 8.4 to 11.2 and demonstrated that significant and reproducible results could be obtained by proper attention to experimental technique. In examining the corrosion of tin under such conditions, it is desirable to know the effects of anions, aside from carbonate, that are likely to be present in commercial materials packaged in tin. Therefore, in this paper the potential behavior of tin in carbonate solutions to which sodium fluoride, chloride, bromide, iodide, sulphate, nitrate, monobasic phos-phate, dichromate, perborate and acetate have been added will be dcscribed. For most of the additions, solutions containing 0.001 and 0.01 moles of the added material were studied. The experimental procedure was exactly the same as that described in the first paper; the pH of the electrolyte was controlled by adjusting the ratio of carbonate to bicar-l,ol~ate as follows: pH 0.1 M NaHC0............................................ 8.4 2 parts 0.1 M XaHCOr, 1 pa.rt 0.1 M NaZCO?................. 9.5 1 part 0.1 M NaHCOs, 2 parts 0.1 M iVa.,C03. ................ 10.0 0.1 M Na2C0............................................. 11.2 The reagents used were all of C.P. grade. The anions studied may be divided into three groups: (1) anions that had little or no effect upon the potential curves—sulphnte, nitrate, and acetate; (2) those that helped to prevent corrosion at low pH only -fuoridc, chloride, bromide, and iodide; (3) those that helped to prevent corrosion at high pH also—phosphate, pcrborate, and chromate. Potential Measurements f The time-potential curves represntative of group 1 are shown in Fig. 1. These are the curves for 0.005 M sulphate ion and their similarity

Jan 1, 1939

By J. P. Van Kleunen

9.3-1. Introduction. The demands of industry for handling materials at higher rates and at reduced costs have had a very significant effect on belt conveyor technology. Although the general appearance of the belt conveyor today is essentially the same as it has been for the past several decades, the similarity ends there. Each component comprising the conveyor system has been continuously improved through design and materials technology to enable present conveyor systems to operate at ever-increasing rates and reliability. For example, twenty years ago the strongest commercially available, fabric-reinforced conveyor belting had a tension rating of 50 lb per ply-in. Currently, fabric-reinforced belts are available with ratings of 350 lb per ply-in. and steel cable reinforced belting is available with tension ratings of 3000 lb per in. of belt width (3). These technological advances have therefore enabled the belt conveyor to not only attain acceptance as a preferred method for in-plant movement of bulk materials, but also to be used for long distance transportation of bulk materials, particularly in areas of adverse terrain. The information contained in this chapter is intended to assist the reader to make basic decisions regarding the use and application of a conveyor system. The design of an overland conveyor transportation system or an in-plant process conveyor is accordingly beyond the scope of this article. Many comprehensive technical works covering the design of a belt conveyor are currently available from the manufacturers of materials handling equipment (6, 7, 9, 11). The design handbook published by the Conveyor Equipment Manufacturers Association is particularly recommended (2). 9.3-2. Conveyor Capacities. One of the most important factors in determining the proper size of a conveyor system is the rate at which material must be handled. Although tables and charts are available to the conveyor designer to assist him in his selection of conveyor components, only the

Jan 1, 1968

Ore deposits of commercial grade are local concentrations of great rarity when considered in relation to the area of unmineralized land surfaces, and they must therefore be considered as the products of exceptional and complex conditions. The data collected from a great number of individual deposits are sufficient to permit certain broad generalizations in regard to the conditions favorable to ore deposition which even numerous exceptions do not invalidate. The broadest general relation of ore deposits is with intrusive rocks, and while there are notable exceptions, the great majority of ore deposits have a visible or closely inferred connection with intrusive rock masses. Conditions that permit the dissipation of the ore-bearing vehicles do not permit the concentration of metals in deposits; the prime factor to consider in this connection is that structural conditions must be such as tend to concentrate and not to dissipate the ore-bearing solutions. The disadvantage of extrusive rocks is at once apparent; any metals the magma may have contained are dissipated at the surface and are lost; with the exception of tiny vugs and cracks in quickly cooled flows, no concentrations of metals are known in extrusive rocks, and the lack of confinement and quick cooling apparently do not permit extrusives to exert mineralizing effect upon the rocks with which they come in contact. The close mineralogical similarity between extrusives and intrusives, and the great difference in mineralizing power is a proof of the ease with which magmas part with their metallic content, and of the mobility of the ore-bearing vehicles in comparison with the parent magma.

Jan 1, 1932

By W. A. McCurdy, Joseph W. Leonard, T. S. Spicer

INTRODUCTION by T. S. SPICER and J. W. LEONARD Utilization from the Point of View of the Preparation Engineer The primary interest of the coal preparation engineer is process design, operation and maintenance to produce an acceptable product which can be sold at the greatest possible profit. Because of these interests, attention to the unrealized potential value of coal is sometimes neglected. The intent of this chapter is to alert the preparation engineer to the utilization possibilities of both the product as well as the tributary coal flow moving through a modem coal preparation plant. Thus, coal types having similar physical and chemical properties tend to become increasingly concentrated according to size, specific gravity and/or surface chemistry. The basis for any unrealized potential derives directly from the coal seam itself. Most coal seams consist of coal bands and benches which are sandwiched together in layers and which visually differ from each other by physical structure and luster. Randomly selected physical and chemical ranges determined from layers of coal in a single seam can easily differ by as much as 30 Hardgrove grindability indices, 0.30 of a specific gravity point, 20 percentage points of ash, six percentage points of dry volatile matter and 10 percentage points of total sulfur.1 Similar wide variations exist for calorific value, seam moisture content and undoubtedly, for any other conceivable coal test parameter which might be used for comparative purposes. These observations all point to the long established fact that coal is not homogeneous as conventional analytical methods might tend to indicate, but is instead a highly heterogeneous substance. Since both coal and associated minerals entering a preparation plant are highly heterogeneous, a multi-product potential beginning with certain flotation cell concentrates and ending with plant refuse may exist. Such a potential can and to a limited extent is achieved at some operations by drawing off coal according to size, specific gravity and/or surface chemistry differences from individual coal cleaning processes. Such a sequenced draw-off of coal of increasing ash increments could yield, among other products, chemical coals, coking coals, coals for pulverized fuel boilers, cyclone boiler coals, coals for cement plants, limestone, shale and clay. Basis for Coal Evaluation and Selection Despite the known heterogeneity of coal, the final analysis of a given coal product is customarily reported as a single average since coal has always

Jan 1, 1968

By William A. Longacre

IN a previous paper1 the author discussed the problem described by the title of this paper, outlining and reviewing the Gish-Rooney method, with comparison and brief analysis of the interpretation techniques of Roman2 and Tagg.3 Some aspects of the simple type of two-layer system were reviewed from various sources.4,5,6 THE TWO-LAYER PROBLEM For the configuration shown in Fig. I, and for any electrode separation A, the apparent resistivity is a function of the relative depth [HA], the overburden resistivity pi, and a factor K defined by the equation [ ] where p2 is the resistivity of the lower bed, Thus, by the known theory of electrical images, [ ] THE MULTILAYER PROBLEM As the number of isotropic, homogeneous, horizontal layers increases, the difficulties of interpretation multiply. The theory becomes much more involved, and in view of the state of our knowledge, the general problem is virtually impossible of exact solution. However, certain types of [ ] multilayer problems can be worked out in terms of two-layer theory. Hummel,7 Pirson,8 Tagg,3 Watson,9 and others have pointed out the possibility of building up approximations of multilayer resistivity curves with suitable combinations of two-layer curves. Many three-layer curves can be constructed in this way to a good degree of accuracy, and special types of four-layer curves can be approximated. It is very likely that as the number of layers increases, the method of combination will not give good approximations except in very special cases, In the analysis of actual field data, the author has found that many obviously multilayer curves can be solved partially with a good degree of accuracy, using the theory that thin adjacent beds may be considered as one layer or zone, and applying two-layer theory to the extremities of the field curve. MODIFIED TAGG METHOD OF INTERPRETATION Tagg's second method, though superior to his first, necessitates a large number

Jan 1, 1941

By Elton A., Youngberg

The Holden mine operated by the Chelan Division of the Howe Sound Co. is on the east slope of the Cascade Range in north central Washington on the south slope of Railroad Creek valley at an elevation of 3500 ft. The mine may be reached by a 40 mile boat trip from the town of Chelan which is at the southern tip of Lake Chelan, to Lucerne at the mouth of Railroad Creek and an 11 mile bus ride up Railroad Creek to Holden. All freight and concentrate is moved over this route to Chelan Falls on the Columbia River which is on the railroad four miles below the town of Chelan. The mine is now producing 2000 tons of gold, copper, and zinc ore per day which is treated in the Holden mill. Gold-copper and zinc concentrates are made, the first of which is shipped to Tacoma, Wash., and the latter to Kellogg, Idaho, for smelting.

Jan 1, 1949

By A. T. Stroebel, J. A. Goodwin

Diatomite deposits, the skeletal remains of tiny aquatic plants called diatoms, are found in many parts of the world. Only a few of these deposits are of commercial value. Open pit mining is used in nearly all deposits now being worked. Processing methods range from simple drying, crushing, sizing and packaging to carefully controlled and highly sophisticated calcining and air classification procedures, employing the latest control and testing techniques. The major uses of processed diatomite are infiltration as filter aids and fillers and extenders.

Jan 1, 1983

By Ralph H. Sweetser

AT the end of 1943 the charcoal pig iron capacity of the United States was at the lowest point in over 1110 years, with only one strictly charcoal blast furnace in operation, and all others permanently out of blast except one in Tennessee d reported to he running on part charcoal and part coke. Such a decrease in production has taken place in spite of the O.P A.'s high-premium price on charcoal pig iron of +34 per ton f.o.b. furnace in Michigan. Depletion of the hardwood supply within fifty mlles or inure of the blast furnace is the reason why; the deplorable lack of reforesting is the cause.

Jan 1, 1944

By William M. Newton, John E. Sherborne

The relation between the properties of electric logs and the fluid used in drilling a well is briefly discussed in this paper, and the fact that the resistivity of the drilling mud and its filtrate can appreciably affect such logs is shown. Apparatus was designed and a procedure established to determine the effect of various factors on the resistivity of drilling mud. Five muds commonly employed in California were tested and the following observations were made: I. The effect of raising the temperature from 80°F. to 180°F. is to decrease the resis-tiviiy of the mud or filtrate approximately 50 per cent. 2. The resistivity of the mud in most cases closely approximates that of its filtrate. 3, The change in the resistivities of muds caused by the addition of chemical is not the same function of the amount of chemical added for each mud. 4. The effect produced by increased sodium chloride content is to reduce markedly the resistivity of the mud and its filtrate. 5. Weighting materials, such as Baroid and limestone, tend to increase the resistivity of drilling mud. 6, Cement and counteracting reagents reduce mud resistivity. Introduction During recent years, the practice of "electrically logging9' a geologic formation by means of a system of electrodes lowered in a well bore has provided data of inestimable value concerning the nature of the sediments penetrated. Thus, it is generally possible, by means of electric logs, to distinguish readily the differences between shales, sandstones, cherts, limestones, and other rock forms. The distinguishing characteristics recorded in this manner have made possible long-range and closely detailed mapping and visualization of deeply buried structures1-5 to a degree not to be obtained with a reasonable expenditure of money by any other means at present in use. Besides being of value in correlation work, electric logs have been found, in some instances, to be useful in estimating the nature of fluid contained within the pores of a rock. In special cases, even the relative permeabilities at different horizons have been determined.6 That electric logs should reflect in some measure such physical properties of rocks as porosity and permeability and, in addition, give rise to data pertaining to the fluid content of rock interstices, becomes evident when the conditions giving rise to the electrical phenomena measured are known. However, it is not the purpose of this paper to review the present status of electric logging; rather, the reader is referred to the papers cited on page 220 for the principles and practice involved. Importance of Drilling FLuid in Electric Logging Because the drilling fluid must be the medium through which the electric logging device is made to traverse the formations penetrated by a borehole, and since, in general, the drilling mud completely surrounds

Jan 1, 1942

By John E. Sherborne, William M. Newton

The relation between the properties of electric logs and the fluid used in drilling a well is briefly discussed in this paper, and the fact that the resistivity of the drilling mud and its filtrate can appreciably affect such logs is shown. Apparatus was designed and a procedure established to determine the effect of various factors on the resistivity of drilling mud. Five muds commonly employed in California were tested and the following observations were made: I. The effect of raising the temperature from 80°F. to 180°F. is to decrease the resis-tiviiy of the mud or filtrate approximately 50 per cent. 2. The resistivity of the mud in most cases closely approximates that of its filtrate. 3, The change in the resistivities of muds caused by the addition of chemical is not the same function of the amount of chemical added for each mud. 4. The effect produced by increased sodium chloride content is to reduce markedly the resistivity of the mud and its filtrate. 5. Weighting materials, such as Baroid and limestone, tend to increase the resistivity of drilling mud. 6, Cement and counteracting reagents reduce mud resistivity. Introduction During recent years, the practice of "electrically logging9' a geologic formation by means of a system of electrodes lowered in a well bore has provided data of inestimable value concerning the nature of the sediments penetrated. Thus, it is generally possible, by means of electric logs, to distinguish readily the differences between shales, sandstones, cherts, limestones, and other rock forms. The distinguishing characteristics recorded in this manner have made possible long-range and closely detailed mapping and visualization of deeply buried structures1-5 to a degree not to be obtained with a reasonable expenditure of money by any other means at present in use. Besides being of value in correlation work, electric logs have been found, in some instances, to be useful in estimating the nature of fluid contained within the pores of a rock. In special cases, even the relative permeabilities at different horizons have been determined.6 That electric logs should reflect in some measure such physical properties of rocks as porosity and permeability and, in addition, give rise to data pertaining to the fluid content of rock interstices, becomes evident when the conditions giving rise to the electrical phenomena measured are known. However, it is not the purpose of this paper to review the present status of electric logging; rather, the reader is referred to the papers cited on page 220 for the principles and practice involved. Importance of Drilling FLuid in Electric Logging Because the drilling fluid must be the medium through which the electric logging device is made to traverse the formations penetrated by a borehole, and since, in general, the drilling mud completely surrounds

Jan 1, 1942

By P. J. Potter

Practically all tin-base babbitt metals used in engine bearings are made to customers' specifications, which are many and varied. The copper ranges from 3 to 8 per cent. and the antimony from 4 to 13 per cent.; generally, the babbitt with lower copper content will contain from 4 to 8 per cent. antimony and that with higher copper will have from 7 to 13 per cent. antimony. The allowable lead content varies from 0.20 to 2.00 per cent. If a solder is used as a bonding material instead of tin, the resulting material in the finished bearing will have a higher lead content, but it would not be enough to bring the lead above specifica-tional limits. Impurities such as iron, arsenic and bismuth should be determined in the tin before using to insure a uniform and high-grade product. These points must be considered when segregating and grading the waste that comes from the finishing operations on lined bearings. Classification of SCRAP Because of the extremely rigid nature of most of the specifications for bearing linings it is necessary to use the purest of materials as a base for all compositions. The problem of handling secondary metals is confined almost entirely to the recovery of drosses, spills and turnings incident to the manufacturing operations. As a matter of convenience the waste or scrap may be divided into 10 grades, as follows: 1. Tin from pots where tinning operation is carried out. 2. Tin and babbitt spatters from babbitting operation. - 3. Tin skimmings combined with burned zinc chloride. 4. Borings and reamings. 5. Gates from die-cast bushings and bearings. 6. Drosses from die-cast pots, babbitt foundry pots, and pots in babbittiug room. 7. Babbitt with small amount of bronze from machining operations. 8. Babbitt and bronze borings. 9. Scrap bronze-back babbitt-lined bearings. I 10. Scrap die-cast bearings and bushings. A few of these grades of salvaged material have compositions that make it possible to determine beforehand where they may be used to

Jan 1, 1930

By J. S. Ross

Few Canadians realize the role of their domestic industrial minerals industry because it is over-shadowed in production value by a large metallic minerals industry. But since 1960, Canada has had a reasonably well balanced, mature industrial minerals industry; and although the nation's sparsely scattered population has not been able to support an industrial minerals industry in a manner comparable to the domestic and foreign support given the metal mining sector, Canada is, nevertheless, exporting large quantities of higher priced nonmetallic minerals. Production of many of the basic minerals had been firmly established long before 1960, but it was not until the late 1950's that the output of cement, salt, titanium dioxide pigment and slag, sulfur, gypsum and sodium sulfate reached relatively high levels. Shortly after 1960, the significant potash and lithium chemicals industries were established and their effect is just now being realized.

Jan 11, 1964

THE CHAIRMAN (A. F. Lucas, Washington, D. C.).-Mr. Matteson has stated that the drilling of certain deep wells has proved a failure because they were abandoned too soon. He advises drilling more wells around salt domes, in the hope of finding additional oil sands. I have had some experience on the domes and believe that by drilling shallow wells, one loses time and money. I have advanced the opinion -that by drilling central wells in the -most likely location of a dome, showing is certain weakness, a better result could be obtained. I have in mind one locality where Mr. Knapp drilled a well through the salt¬the only location that I know of on the Gulf Coast where oil was found underneath the salt. Mr. Knapp found a great deal of gas in it. The salt itself was impregnated with oil and gas; and my opinion is that in such instances, instead of drilling so many wells around a dome, if you will attack at a weak point to as great a depth as a drill will go, the results will he much better. At present we have instances where drills have penetrated to 7300 or 7400 ft. in depth. Why couldn't the rich companies that are operating around the Gulf Coast arrange to get some special drilling apparatus and drill with the rotary first for, say, 3000 to 4000 ft., always in the likely location, and then proceed with the cable? I think we need just such work. In Mr. Matteson's paper lie quotes from an author whose writings in the Federal Bulletin and in the Louisiana Bulletins have been quite extensive. He states that oil and asphalt have originally been found on the surface of those domes. I have been over and examined nearly all of those domes (not all of them, because many have been developed in the last few years) and found no such occurrence at the time; and in the old well-known humps or big hills, as they generally called them; I have never found either salines or asphalt or petroleum. In only' one instance it looked as though asphalt night have exuded out of the ground, and that was in the Sour Lake, but right in that neighborhood years previous to that a company had operated commercially-they had a little refinery there-and had found it so unprofitable that they pulled up stakes and quit.

Jan 4, 1918

By L. W. Reynolds, R. F. Campbell, K. G. Carroll, S. H. Ballard

Based on metallographic and X-ray data probable equilibrium conditions from 1340" to 2400°F are presented for the composition range investigated. These are correlated with investigations of Takei and Kuo. Provision is made for existence of Mo, C and (Fe, Mo)2,C, carbides heretofore omitted in diagrams in this composition range. These carbides and (Fe, Mo),C, in equilibrium with ferrite and austenite, restrict the austenite and austenite + ferrite fields to lower carbon contents and higher temperatures than in the Fe-C system. OK groups of steel of different molybdenum content, but with approximately the same carbon variation in each group, Table I, were studied. The alloys were melted in an acid-lined 30-lb high-frequency induction furnace, and the ingots forged to l-in. rounds, which were then ground to 0.75-in. diam. To minimize chemical segregations a short length of each bar was given a high-temperature heat treatment as listed in Table I. Specimens 0.062 to 0.125-in. thick were thereafter cut from the homogenized bars for heat treatment to determine phase changes in the alloy. Heat treatments were performed in either a lead bath or muffle-type electric furnace, depending upon the temperature required. Maximum temperature variation was * 2" F in the lead bath and * 5"F up to 1900°F and +8"F above 1900°F in the electric furnace. Adequate protection of the specimen from the oxidizing atmosphere in the electric furnace was obtained by sealing the specimen in either a pyrex or a silica capsule which was evacuated or not as circumstances required. For austenitizing followed by quenching to an isothermal temperature, the specimen was placed in a closed-end refractory tube the mouth of which, extending beyond the furnace, was connected to a vacuum pump. The specimen could be withdrawn from this tube and quenched as desired. IDENTIFICATION OF PHASES The principal method of identification of phases was metallographic examination conducted on surfaces well removed from exposure to lead or atmosphere effects during heat treatment. Hardness measurements (Dph/lOkg) were also made on these surfaces. The etching reagents used and their effects are listed in Table II. Martensite and ferrite were readily recognized by their customary appearance after etching with saturated picral or 1 pct nital. The presence of liquid at high temperature was indicated by curved interfaces characteristic of boundaries between solid and melt, by intergranular pools of dendritic areas in a carbide matrix, and by a black network coincident with austenite grain boundaries. Examples of these structures are shown in Figs. l(a) and (0). The types of carbide which were attacked by the electrolytic chromic acid etch and the alkaline KMnO, etch, Table 11, were identified by X-ray analyses of extracted carbides of five alloys. Carbide residue was obtained from a metallographic specimen by etching the specimen for 24 hr in hydrochloric-picric acid in alcohol (grain-size reagent), after which the carbides, standing in relief, were scraped from the surface of the specimen and mounted on a glass slide. Diffraction patterns were obtained with a Philips spectrometer using iron-filtered cobalt radiation. Figs. 2, 3, 4, and 5 illustrate typical etching behaviors with chromic acid and alkaline KMnO,. Chromic acid attacked Mo,C as shown in Figs. 2(a) and (b)-but not (Fe, Mo),C, Fig. 3(b). Alkaline KMnO, attacked (Fe, Mo),C, Fig. 3(c), and also attacked M0,C. In accordance with these behaviors, a typical differentiation of coexisting Mo,C and (Fe, Mo),~ is shown in Figs. 4(a) and (b). The carbide (Fe, Mo),,C, could not be obtained free of other coexisting carbides for etching experiments. The behavior. however. of coexisting carbides identified by x-ray diffraction as Mo,C ind (Fe, Mo),,C, indicate that (Fe, Mo)23C6 is not etched by chromic

Jan 1, 1961

By Harry K. Ihrig

Jan 1, 1947

By Harry K. Ihrig

Jan 1, 1947

By C. Everard Arnold

The Giroux Consolidated Mines Co. is equipping a five-compartment shaft at Kimberly, Nev., which will serve the Alpha mine. The depth of this shaft, January, 1910, is 963 ft., and of this depth 948 ft. was opened by raising; 15 ft. of sinking was done so that the bearers, collar-set, and three shaftrsets might be installed and concreted, and with this done it mas possible to erect the necessary surface-equipment for resuming shaft-timbering on the completion of the raise. The arrangement of the shaft-timbering is shown in Fig. 1. At the 1,000-ft. level of the Alpha, and 750 f't. SW. from the Alpha shaft, a 14- by 18-ft. station was cut, and a 25-h-p. airhoist was installed. From here the raising commenced on July 5, 1909. The raise was cut approximately 13 by 21 ft. in area, and supported by timbering with square sets, illustrated in Fig. 2, which shows the division into four compartments. The end compartments, which were used as chutes, had the center girts heavier than in the others on account of the wear from falling rock. The chute-lining was braced by inserting 8- by 8-in. stiffeners parallel to and half way between successive caps. Similarly, the lagging on the wall sides of the cage-way and the compartment for pipes and ladder was stiffened with 4- by 6-in. timbers. In the pipe-and-ladder compartment the chute-stiffeners were reinforced with 8-by 8-in. struts, and as the cage-way was partitioned off by braced lining, there was practically no chance of rock entering the ladder-way in case a chute burst into the cage-way. Over the two center compartments the last two sets were always bulkheaded with 8- by 12-in. timbers, shown in Fig. 3, and from the lower bulkhead the cage sheave-wheel was suspended. After a round of holes had been blasted and the loose

Jan 1, 1911