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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 John F. Shaw

The Denver Mining Research Center headquartered at Denver, Colo., is typical of the new research units recently activated as a result of increased emphasis by the U. S. Bureau of Mines on research concerned with metal and nonmetal (except mineral fuels) ore extraction. The Denver Center, together with the recently established Minneapolis Research Center and the Offices of Mining Research at Reno and Spokane, and the older, well-known Applied Physics Research Laboratory at College Park, Md., share the responsibility for the comprehensive mining research program. The Denver Center specializes in two areas of research: (1) The development of engineering principles and mathematical techniques applicable to exploration, development and operational problems in mining, and (2) the study of rock mechanics as applied to ground control. The first area presently includes three categories: research on methods of ore sampling, mine-systems analysis, and applications of statistics to problems of mineral exploration. The second area emphasizes research in two main categories: laboratory investigations designed to develop a fuller understanding of how rock be- haves under the loads imposed by mining, and field investigations to evaluate stress-strength relation- ships in full-scale, operating mines.

Jan 3, 1962

By AIME AIME

ALTHOUGH the retiring Chairman of the Industrial Minerals Division, Charles Henry Behre, Jr., does not say "you all" he is a product of the deep South, since he was born at Atlanta, on March 16, 1896. At the Boy Scout age he moved to New Orleans, where his father owned an ice plant, which seems an intelligent business for that climate. Intelligence evidently runs in the family, for Charlie, as his friends call him, has one sister who is a professor of zoology and another who is a concert pianist. Charlie has no explanation of why, when he reached college age, he decided to go to the University of Wisconsin, other than something more than an ordinary boyish interest in science, and the reputation which Wisconsin then enjoyed. At Madison he fell under the influence of Eliot Blackwelder, chose paleontology as his objective, and transferred, at the end of his sophomore year, to the University of Chicago, where the paleontological panorama seemed more extensive. He took his B.S. there in 1918, and graduated into the U. S. Army, where he eventually became a Sergeant in the Medical Corps.

Jan 1, 1945

By J. R. Long, C. E. Armantrout, A. H. Roberson, T. R. Graham, R. S. Dean

THE general program of the Federal Bureau of Mines on the study of alloys made with electrolytic manganese has been extended to copper-manganese-aluminum alloys. The initial results of the work are presented in this report and concern a determination of the mutual solubilities of these three metals to form the alpha solid solution. The principal studies of this system, reported in the literature, have been focused on the Heusler alloys containing 10 to 30 per cent Mn with 9 to 15 per cent Al. These investigations concern the ferromagnetic properties and the determination of the crystallization contours, with little emphasis on the phases present in the solid state outside of this area. Heusler1 recognized a breakdown of the beta solid solution of the magnetic alloy, which he says decomposes into the alpha, beta, and gamma phases of the copper-aluminum system, somewhat modified by the presence of manganese. Rosenhain and Lantsberry2 examined alloys ranging up to 10 per cent Mn and io per cent Al but were unable to reach definite conclusions concerning the phase boundaries in that area. Krings and Ostmann3 made magnetic studies and examined the system by thermal analysis. They present contours of the liquidus surface but do not place any of the phase boundaries. Corson4 [ ] has drawn a hypothetical boundary for the alpha field with few data to support such construction. The binary systems involved have received considerable attention by numerous investigators, and their general features are well established. The hopper-aluminum system (Fig, I) has been thoroughly examined by Stockdale,5 who places the limit of solubility of aluminum in copper at 7.4 per cent at the liquidus and 9.5 per cent at room temperature. Smiths established the eutectoid temperature at 570°C. by a study of isothermal decomposition of the beta phase. The copper-manganese system (Fig. 2) has been recently reviewed by Dean and co-workers.7 Using high-purity alloys, they place the solubility of alpha man-

Jan 1, 1946

By C. S. Barrett

IT has been observed that deformation in iron takes place by slip on {110} + {112} + {123} planes1,2 but in silicon ferrite with low deforma-tion temperatures or high silicon contents (exceeding 4 per cent) the authors have found that slip is confined wholly to {110} planes, at least with small amounts of deformation. The purpose of the present inves-tigation was to determine the effect of this alteration of slip mechanism on preferred orientations in cold-rolled and recrystallized strips. Inci-dental observations on the effect of the recrystallization temperature were also made. The numerous determinations of the texture of cold-rolled iron and steel have been in satisfactory agreement as to the principal features of the texture. (with the exception of a few conclusions that apparently have been based on insufficient data). The texture is chiefly one in which [110] directions of the grains lie along tile direction of rolling, with a deviation of a few degrees, and in which the (100) planes lie in the plane of the rolled sheet, with a deviation from this position chiefly about the rolling direc-tion as all axis 3-9. This deviation about the rolling direction as an axis has been measured by different observers and lies between about 45° and 50° or 60° for iron5,6,9 and is usually in the neighborhood of 50° for mild steel6,7,8. The range of this deviation is a function of the percentage of total reduction 8, 10. Post' reported that it decreases with increasing percentage reduction, but apparently he .studied only the surface material, which Gensamer and Mehl7 found to be somewhat differently oriented from the material in the inside of the sheet. McLachlan and Davey10 found that the deviation also decreases with increasing percentage of total reduction for the material in the interior of the sheet and is independent of the percentage of reduction per pass.

Jan 1, 1937

By R. S. Dean. J. R. Long T. R. Graham, Roberson A. H., Armantrout C. E.

The general program of the Federal Bureau of Mines on the study of alloys made with electrolytic manganese has been extended to copper-manganese-aluminum alloys. The initial results of the work are presented in this report and concern a determination of the mutual solubilities of these three metals to form the alpha solid solution. The principal studies of this system, reported in the literature, have been focused on the Heusler alloys containing ro to 30 per cent Mn with 9 to 15 per cent Al. These investigations concern the ferromagnetic properties and the determination of the crystallization contours, with little emphasis on the phases present in the solid state outside of this area. Heuslerl recognized a breakdown of the beta solid solution of the magnetic alloy, which he says decomposes into the alpha, beta, and gamma phases of the copper-aluminum system, somewhat modified by the presence of manganese. Rosenhain and Lantsberry2 examined alloys ranging up to 10 per cent Mn and 10 per cent A1 but were unable to reach definite conclusions concerning the phase boundaries in that area. Krings and Ostmann3 made magnetic studies and examined the system by thermal analysis. They present contours of the liquidus surface but do not place any of the phase boundaries. Corson4 has drawn a hypothetical boundary for the alpha field with few, data to support such construction. The binary systems involved have rcceived considerable attention by numerous investigators, and their general features are well established. The copper-ahminum system (Fig. I) has been thoroughly examined by Stockdale,5 who places the limit of solubility of aluminum in copper at 7.4 per cent at the liquidus and 9.5 per cent at room temperature. Smith6 established the eutectoid temperature at 570°C. by a study of isothermal decomposition of the beta phase. The copper-manganese system (Fig' ') has been recently reviewed by Dean and CO-WorkersS.7 Using high-purity alloys,

Jan 1, 1947

By Armantrout C. E., R. S. Dean. J. R. Long T. R. Graham, Roberson A. H.

The general program of the Federal Bureau of Mines on the study of alloys made with electrolytic manganese has been extended to copper-manganese-aluminum alloys. The initial results of the work are presented in this report and concern a determination of the mutual solubilities of these three metals to form the alpha solid solution. The principal studies of this system, reported in the literature, have been focused on the Heusler alloys containing ro to 30 per cent Mn with 9 to 15 per cent Al. These investigations concern the ferromagnetic properties and the determination of the crystallization contours, with little emphasis on the phases present in the solid state outside of this area. Heuslerl recognized a breakdown of the beta solid solution of the magnetic alloy, which he says decomposes into the alpha, beta, and gamma phases of the copper-aluminum system, somewhat modified by the presence of manganese. Rosenhain and Lantsberry2 examined alloys ranging up to 10 per cent Mn and 10 per cent A1 but were unable to reach definite conclusions concerning the phase boundaries in that area. Krings and Ostmann3 made magnetic studies and examined the system by thermal analysis. They present contours of the liquidus surface but do not place any of the phase boundaries. Corson4 has drawn a hypothetical boundary for the alpha field with few, data to support such construction. The binary systems involved have rcceived considerable attention by numerous investigators, and their general features are well established. The copper-ahminum system (Fig. I) has been thoroughly examined by Stockdale,5 who places the limit of solubility of aluminum in copper at 7.4 per cent at the liquidus and 9.5 per cent at room temperature. Smith6 established the eutectoid temperature at 570°C. by a study of isothermal decomposition of the beta phase. The copper-manganese system (Fig' ') has been recently reviewed by Dean and CO-WorkersS.7 Using high-purity alloys,

Jan 1, 1947

By AIME

WELL known as an outstanding practical metallurgist, the Chairman of the Institute of Metals Division also possesses a rare combination of research and administrative abilities. Louis W. Kempf was born in Muskegon, Mich., on March 22, 1898. Following his graduation from high school, he obtained considerable experience in the automobile industry while employed by Continental Motors, the Studebaker Corp., and Dodge Brothers. He enlisted in the U. S. Army Signal Corps in 1917, and served overseas with an aviation unit. In 1919, Mr. Kempf entered the University of Michigan and earned both B.S. and M.S. degrees. While there he was elected to Tau Beta Pi, Phi Lambda Upsilon, Alpha Chi Sigma, and Gamma Alpha. In 1924, the Aluminum Co. of America secured his services as a research metallurgist. With a steady job he married Elizabeth Skelley in Cleveland in 1926. They have one son now seventeen. After six years Mr. Kempf was made manager of the Cleveland research division of the Aluminum Research Laboratories which position he held until last year. In 1945 he was promoted to assistant director of the Laboratories. He will direct research involving process metallurgy in Cleveland and New Kensington.

Jan 1, 1946

By Scott Turner

OUR Institute, in its annual Directory, states the following: The purpose of each Technical Committee is to further the development of the special mineral industries in its field, chiefly through obtaining and discussing papers suitable for publication by the Institute. The proper field of the new Health and Safety in Mines Committee is judged to include the entire mining industry, and involves the multitude of health and safety problems arising in all kinds of mining operations. The mining industry in the United States has made much progress during recent years in reducing accidents. This advance has been widespread, and has been especially notable in the mining of iron ore. Yet the statistics of the U. S. Bureau of Mines, when compared with figures of the National Safety Council for other industries, show that mining still has a higher personal mishap rate than any other major industry in this country. In addition, studies of dollars-and-cents cost of casualty occurrences indicate that an important part of our mining cost, held by various authorities to be as much as 10 per cent of the total, is due to accidents.

Jan 1, 1933

By W. Rogers Wade, Alfred Wandtke

The Pilares mine of the Moctezuma Copper Co. is situated at Los Pilares de Nacozari, Sonora, Mexico, about 75 mi. (120.7 km.) south of the international boundary and about 7 mi. (11.26 km.) east of the town of Nacozari de Garcia. It is situated at an elevation of 5000 ft. (1524 m.) in one of the northward trending ridges that form part of the mountain mass that culminates in the Sierra Madre de Mexico. To the east, south, and west, the topography is rugged and diversified; to the north less diversity exists, ranges of mountains rise sharply out of almost level ground and give the basin range structure characteristic of the Southwest. The climate is dry, the average rainfall of 15 in. (38 cm.) being confined almost entirely to the months of June, July, and August. The winter consists of a few days of disagreeable weather when a little snow may fall; the remainder of the year is thoroughly delightful. Vegetation is typical of a semi-arid region. In the canons near the mine, where water flows intermittently, willows thrive; on the northern slopes of some of the mountains and in some of the broader canons pines may even become abundant. The dominant rocks are flows and pyroclastics which are cut by dykes, stocks, and batholiths. The mountain just west of Nacozari is, in part, composed of limestone of an unknown age which occurs as a syncline and is undoubtedly a part of a prevolcanic land surface. Overlying the limestone and faulted against it, are the volcanics; cutting the limestone is a coarse biotite granite. Whether the granite is older or younger than the volcanics has not been definitely established. No attempt has been made to differentiate the rock types of the volcanic~, of which there are exposed 3000 ft. (914 m.) in thickness of basic and acid flows (andesites, latites, and rhyolites) and andesite and latite tuffs and breccias. The latite breccias, the youngest of these volcanic~, cover the highest mountains in the immediate vicinity. The

Jan 1, 1920

By W. P. Sykes

SINCE Honda and Murakami1 in 1918 proposed their constitutional diagram of the carbon-free iron-tungsten system, considerable effort has been expended by several investigators in attempts to define more positively the structural features of the alloys. The existence of an intermediate phase corresponding to the formula Fe3W2 (68.7 per cent W) was proposed from evidence of a purely metallographic nature by one of the present authors2 in 1926. Since that time the identity of this phase has been confirmed by Arnfelt3 and by Takeda,4 both of whom employed X-ray methods as well as the microscope and the chemical analysis of isolated microconstituents. According to Arnfelt, Fe3W2, as crystallized from the iron-rich melts at a temperature above 1450'C., contains by analysis 68.7 per cent W. The lattice of this phase is characterized by trigonal symmetry. Arnfelt, moreover, proposed a second intermediate phase formed at some temperature between 1450° and 1000° C. by a peritectoid reaction involving Fe3W2 and the iron-rich solid solution. A melt containing 25 per cent W was cooled to 1000° C. and heated for. 100 hr. The precipitated tungsten-rich constituent was separated and found by analysis to contain 62.6 per cent W. This composition agrees closely with that represented by the formula Fe2W (62.2 per cent W). Diffraction patterns from the concentrated precipitate showed a hexagonal unit cell. Takeda confirmed the data of Arnfelt regarding Fe3W2 but was unable to detect Arnfelt's second intermediate phase. While Takeda. failed to describe in detail the treatments employed, he stated that in alloys containing 40 per cent W which were quenched after heating at various temperatures between 1200° and 1450° C., no evidence of the second phase (Fe2W) was observed either in the microstructure or in the diffraction patterns of isolated residues. He therefore considered the existence of this low-temperature hexagonal compound as disproved.

Jan 1, 1932

By John G. H. Crump, E. W. Owen, Peter P. Gregory

A noticeable decrease in activity characterized the year 1938 in the West Texas area. The total number of wells completed dropped to 2045 for 19381 as compared with 2806 completions in 1937,l a decline of 27.12 per cent. This trend contrasts the sharp increase of 76.29 per cent in completions in 1937 over the 1936 total. Of 2045 well completions during 1938,' 1788 were oil wellsll 16 were gas producers1 and 241 were listed as failures.' During 1938 the ratio of dry holes drilled to oil-producing or gas-producing wells completed was one dry hole to each 7.48 oil wells, which compares with one dry hole drilled to each 7.477 oil wells in 1937. Nearly 200 wells drilled during 1938 in West Texas were either wildcat or partly wildcat wells, an increase of about 25 over the year 1937, when approximately 175 wells drilled were so classified. The 200 exploratory wells drilled represent about 10 per cent of the total number of wells completed. West Texas produced 71,257,541 bbl.1 of oil in 1938 as compared with 75,743,000 bb1.2 of oil in 1937, a decrease of 4,485,459 bbl., or a 5.92 per cent decline. By comparison, West Texas produced 22.36 per cent more oil in 1937 than during 1936. In December 1938, the 9247 producing oil wells in West Texas1 averaged 22.08 bbl. per day per well as compared with December 1937, when 7571 wells1 produced an average of 25.18 bbl. per day per well, or a decline in daily well average of 12.32 per cent. Discoveries No outstanding new fields were discovered in West Texas during 1938, in spite of continued, active wildcatting operations. Several new oil-producing areas were, found, however, the value of which is still unknown.

Jan 1, 1939

By E. W. Owen, John G. H. Crump, Peter P. Gregory

A noticeable decrease in activity characterized the year 1938 in the West Texas area. The total number of wells completed dropped to 2045 for 19381 as compared with 2806 completions in 1937,l a decline of 27.12 per cent. This trend contrasts the sharp increase of 76.29 per cent in completions in 1937 over the 1936 total. Of 2045 well completions during 1938,' 1788 were oil wellsll 16 were gas producers1 and 241 were listed as failures.' During 1938 the ratio of dry holes drilled to oil-producing or gas-producing wells completed was one dry hole to each 7.48 oil wells, which compares with one dry hole drilled to each 7.477 oil wells in 1937. Nearly 200 wells drilled during 1938 in West Texas were either wildcat or partly wildcat wells, an increase of about 25 over the year 1937, when approximately 175 wells drilled were so classified. The 200 exploratory wells drilled represent about 10 per cent of the total number of wells completed. West Texas produced 71,257,541 bbl.1 of oil in 1938 as compared with 75,743,000 bb1.2 of oil in 1937, a decrease of 4,485,459 bbl., or a 5.92 per cent decline. By comparison, West Texas produced 22.36 per cent more oil in 1937 than during 1936. In December 1938, the 9247 producing oil wells in West Texas1 averaged 22.08 bbl. per day per well as compared with December 1937, when 7571 wells1 produced an average of 25.18 bbl. per day per well, or a decline in daily well average of 12.32 per cent. Discoveries No outstanding new fields were discovered in West Texas during 1938, in spite of continued, active wildcatting operations. Several new oil-producing areas were, found, however, the value of which is still unknown.

Jan 1, 1939

By Werner Ostertag

A series of rare earth cobalt compounds of the composition RCoa (r = Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Ev, Tm, Lu) has been prepared. The compounds crystallize in space gvoup R3m and are isomorphous with PuNi3. Except for CeCo3 and PrCo, the series shows decreasing- values of a. and co. The relalively small parameters of CeCo, and PrCo, are explained by valencies of cerium or praseodymium which exceed the usual rare earth valency of three. The structure of the compounds is discussed as in-fillings of kagome nets in direct and staggered superposition. In the course of a systematic investigation of rare earth cobalt compounds"2 and their magnetic properties,, a series of alloys corresponding to the formula Rco3 has been prepared. The investigation of the Rco3 series was stimulated by our investigation of the yttrium cobalt system2 as well as by reports in the literature: Smith and Hansen4 reported the structure of YcO3 and Van vucht5 that of GdCo3; ceco3,6 Gdco3,7 and DyCo3 7 have been found to be single-phase during phase diagram studies. It was the purpose of this work to report crystallographic data on the entire Rco3 series and to interpret the structure of these compounds on the basis of general principles as discussed by Frank and Kasper.8 At the time this work was terminated, it was learned that a similar investigation has been carried out independently by Bertaut, Lemaire, and schweizer.9 Except for CeCo3 (ao = 4.952, co = 24.73') and NdCo3 (a0 = 5.067, co = 24.76') data of this work are in satisfactory agreement with their investigation. EXPERIMENTAL TECHNIQUES A series of samples having the composition Rc03 was prepared from stoichiometric amounts of the rare

Jan 1, 1968

The importance, validity, and acceptability of the Paley Report has become the great issue of the minerals industry. A 12-man panel made up of representatives of various facets of the industry sat down at the 1952 Mining Congress Show in Denver in an attempt to clarify the many opinions currently held concerning the report. Howard Young, deputy administrator of the Defense Materials Procurement Administration, noted that the report had caused more discussion and serious thinking than any other government report, He did not subscribe to the "have not" principle, however, but called it a "need more" principle. Horace M. Allbright, president of U. S. Potash Corp., believes industry should continue to develop the report. He cited the editorial appearing in the September, 1952 edition of Bining Engineering,,, "Don't Let It Die," as expressing his feelings. Edward Snyder, president of Combined Metals Reduction Corp., says the statistics used in the report were used to promote a false international policy. He sees the report as a master plan for the development of the superstate. He also stated that the-ore reserves given in the Pales, report represent only 10 pct of what is actually available.

Jan 1, 1952

Discussion of the paper of Blarney Stevens, presented at the Butte meeting, August, 1913, and printed in Bulletin No. 79, July, 1913, pp. 1285 to 1303. F. L. GRAMMER,Leesburg, Va. (communication to the Secretary*):¬ Mr. Stevens refers to an explanation of parallel jointing by W. 0. Crosby, which I noted when reading one of his excellent text books. It seemed to me earthquakes were not a satisfactory explanation, and I looked up several authorities; but I never realized how small the usual amplitudes were until Mr. Stevens presented his paper. Several letters to the U. S. Geodetic Survey showed me there were very few records of tidal movements of earth crust in the United States. Altitude and latitude would be influencing factors; but this diurnal movement must exceed earthquake amplitudes, besides being more nearly universal. My inquiries brought the answer that the major directions of jointing had not been extensively tabulated. If major directions of jointing were recorded-with notes as to angle with mountain chain, or North Star, and distance between joints, with nature of rock and maximum and minimum tidal up-heaval-some interesting relations might be made manifest.

Jan 11, 1913

By B. C. Burgess

AFTER many years of close and friendly association with talc and soap-stone, this orthographically distinguished mineral steps forth in this edition, for the first time in a chapter of its own. Pyr, the Greek for fire, and phyllite, a rock or stone, form its name and at the same time refer to the first recorded use of pyrophyllite as firestones or hearthstones. Another derivation of "phyllite" is from the Greek phyllites, "of leaves," alluding to the beautiful white radial crystal aggregates that form when pyrophyllite is heated. Pyrophyllite used by the Chinese for carving is called agalmatolite, from the Greek agolma, meaning an image. COMPOSITION AND PROPERTIES Pyrophyllite has previously been grouped with talc because of the close similarity of the minerals in physical and optical properties. They have the same space group; and chemically they are closely related, pyrophyllite being the aluminum silicate A12Si4010(OH)2 and talc the magnesium silicate Mg3Si4010 (OH) 2. Another arrangement of the pyrophyllite formula is generally given as A12034Si02H20 because it expresses the chemical composition as usually determined (alumina 28.3 pct, silica 66.7 pct, water 5.0 pct). Vanderbilt gives pH values of pyrophyllite 5.6 to 8.4.29 Pyrophyllite usually is white, pale green, cream or pale yellow, buff or light gray. It is found in darker shades and other colors principally due to oxidation of contained iron minerals. It is translucent in thin sections. In hardness it is 1 to 2 in the Mohs scale. Its specific gravity is 2.8 to 2.9. In bulk specific gravity, the powdered mineral ranges from 0.4 to 0.7. Its luster is pearly to dull; it is infusible in the Bunsen burner flame, slightly affected by aqueous solutions of sodium carbonate and hydrochloric acid. It is decomposed by sulphuric acid, with separation of gelatinous silica. It is characterized chiefly by its micaceous structure and cleavage, its softness and greasy feel. Two other varieties occur

Jan 1, 1949

R. W. Raymond, New York City: In connection with the subject of multiple tuyeres, my attention has been drawn to the practicability of gaining, without the multiplication of tuyeres, the advantages which that measure is intended to secure ; and learning that this had been attempted in the invention of the Gaines radial-discharge or fan-shaped tuyere, I wrote to Messrs. Gustafson Brothers, of Sequachee, Tenn., who manufacture that tugere, for information concerning the invention itself and its performance in practice. To their courtesy I am indebted for most of the facts given below. I present these statements without expressing any personal opinion on the subject (having no personal knowledge of it), for the purpose of bringing this device to the notice of members, and calling forth both criticism and testimony concerning it. Admitting that definite advantages are to be secured by the multiplication of tuyeres, we must still confess that this change involves considerable expense in the increased number of blastpipes, tuyeres, coolers, connections, and pipes for water-circulation. There is, moreover, a serious question involved in the weakening of the furnace-wall by extra perforations. This consideration applies with special force to furnaces already built without reference to such an increase of tuyere-openings. Ledebur, in his Handbuch der Eisenhüttenkunde, says on this point (I translate from the edition of 1893, page 365): "A limit to increase in the number of tuyeres is given, in any case, by the circumstance that the perforation of the wall weakens it; in other words, that there must be left between the tuyeres a mass of masonry sufficient to carry the parts above. In most cases an appropriate number may be secured by giving to the furnace as many openings as there are meters in its circumference at the tuyerelevel. For instance, for a hearth-diameter of 2.5 meters, i.e., a circumference of 7.7 meters, seven or eight openings might be made, of which, however, one would

Jan 1, 1899

By John B. Hastings

TEN miles from Hartsel, near Antelope springs, in Park county, Colorado, there is a large area of unconsolidated lake beds, which are interesting because at least a part of the lacustrine sands contains in the aggregate an immense amount of gold. During 1906, one of the arms of this dessicated lake was fairly well prospected with shafts and cuts by an Eastern company to test its value, as favorable amounts of gold had in some instances been found upon it. The claims of the company contain about 5,000 acres of the beds; but this is only a small portion of them, a south branch from a main body, which is at least 7 miles in diameter, with other and very wide lateral gulches, paralleling the one herein described on the east and west. A certain amount of digging and sampling was done in the outside areas; but the result was evidently unsatisfactory, since the work was discontinued. his section of Colorado has not been studied geologically, and the age of the ancient lake is unknown. It is probably Quaternary. I spent two weeks on the ground, in September and October, 1906, but was quite absorbed in the sampling. I looked, however, for terraces on the rim-rock and other evidences of movement and erosion, but did not find anything to denote an earlier age than the Quaternary. The granite rim-rock may be Archean; S. F. Emmons says that some of the granites in central Colorado are as old as that. The rim-rock as observed is a gray quartzose biotite-granite, except a small area in Sections 3 and 34, where it is a felsitic (?) breccia. The breccia is silicified by solfataric action at the corner near Shaft No. 7, in Section 34; but this action is older than the sands and does not extend to them. The shaft averaged 50c. per ton, more than twice as much as the rest.

Jan 5, 1908

By Charles M. Means

A thoroughly modern coal-handling system has been installed at the Pittsburgh Terminal H. H. &. Coal Co.'s new No. 8 shaft, or Cover-dale mine, about 11 mi. (17.7 km.) from Pittsburgh on a spur of the Montour R. R. The Pittsburgh scam, which is the one worked, is reached at a depth of 342 ft. (104 m.). Power is delivered to the mine at 22,000 volts over a transmission line of the bow-arrow type of construction. A private telephone line connecting the various mines and the main office in Pittsburgh is carried on the same poles. The high-tension line is brought to an outdoor, step-down, transformer substation, where three 833-kv.-a., single-phase, 60-cycle, oil-insulated, self-cooled transformers reduce the potential to 2300 volts. The transformers are protected by electrolytic, aluminum-cell lightning arresters, horn gaps, and choke coils. High and low-tension busses, together with fuses, choke coils and air-break horn-gap switches with thcir remote-control operating mechanism are mounted on a substantial structural-steel tower 25 ft. (7.6 m.) in height. Mine Substation The transformer substation is adjacent to a. pressed-brick building that houses direct-current substation equipment together with switchboards, etc., for the control and distribution of power. This building also contains the hoist for the men and supplies. Main Switchboard The 2300-volt circuit is carried underground in a conduit from the transformer substation to an oil switch in the substation and supply hoist building. This is the main switch controlling the 2300-volt busbars mounted back to a twelve-panel black-slate switchboard. From the switchboard, 2300-volt circuits are carried to transformers feeding the street and house lighting systems and to other transformers furnishing power for the elevator and lighting circuits in the store building. Other 2300-volt circuits run from this switchboard to the main hoist building, fan house and auxiliary or man-and-supply hoist. High-tension wiring,

Jan 1, 1922