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By H. E. Kramm

During the summer of 1910, I had the opportunity to study in detail the geological conditions of what is known in northern California as " Harrison gulch," in Shasta county. Though the district, as a whole, that is, the western part of Shasta and the eastern part of Trinity county, has contributed during the last 15 years a considerable share of the gold-production credited to Shasta county, very little is known of its geology, perhaps because the country is covered with a dense growth of brush which makes exploration and prospecting extremely difficult. Topographically the district presents a succession of ridges trending approximately N-S., and alternating with deep, narrow canyons. The drainage is partly into the Sacramento, partly into the Trinity river. Climatic conditions in summer time are almost ideal. It is true, the thermometer may climb to 115°, but the air is dry

Jan 1, 1913

By Owen F. Jensen

CONSTRUCTION of a ground-water supply includes many operations, which do not end with completion of facilities. Evaluations must be made of the quality of water in various areas and the history of production. Following an analysis of geologic, hydrologic, and chemical data there must be an exploratory drilling program and a study of resulting information. When the well is completed a continuous survey of operating records and basic data is necessary, since designs for future wells are varied as more data becomes available for those already completed. As the following discussion must be limited to a single undertaking, the customary procedure will be outlined for development and construction of a ground-water supply in which more than three wells are involved. Parts of this procedure are applicable for all ground-water supplies. Three possible sites were selected for construction of a paper mill. The problem was that the industry daily required approximately 15 million gallons of water of the best quality available; however, if water of the best quality were not available in the desired amount, water of a poorer quality could be used up to half the required amount, about 7 million gallons. In the preliminary survey approximately 1500 to 2000 square miles were covered for each site. Collected data consisted of several hundred electric logs of oil and gas wells; reports by the U. S. Geological Survey on ground-water resources of localities in and near the area; unpublished records of several hundred water wells including chemical analyses of the water produced and drillers' logs of the wells; records of periodic water-level measurements made in observation wells by the USGS; topographic maps drawn up by USGS and by army engineers; and highway and county road maps. A preliminary report based on study and evaluation of these data was presented to the client, recommending the site with the most favorable and economical ground-water conditions. The study indicated that water of the quality and quantity desired could be developed. In this particular area there were indications that the aquifer could be separated into two zones con- taining water of different chemical character. This chemical character varied somewhat with area, but principally with depth, a factor which later proved an economic advantage in design of the well field. After studying the preliminary report, the client weighed other economic factors as well as ground-water advantages and selected a plant site. Authority was given to proceed with detailed study of the chosen area. Evaluation of preliminary data concerning the area indicated that it should be supplemented with additional information derived from actual exploratory drilling and testing. A flexible plan of exploratory drilling was devised so that data obtained as each test hole was drilled could be correlated with existing data and additional test holes could be located and drilled accordingly. Specific data to be obtained from each test hole were: samples of all formations penetrated; the driller's descriptive log of formations; electric logging surveys; one or more samples of water from selected water-bearing formations; temperature; and water levels and their recovery after periods of production. The area studied in such detail was approximately 400 square miles. Choice of location for the original test holes was based on the preliminary study. The pattern for these test holes was designed to require a minimum number of holes and to allow for interpolation of data between two, three, and four holes. Geologic, hydrologic, and chemical data gathered after completion of the first four test holes showed that the north section was the most desirable in the area, which was then reduced from the original 400 square miles to about 150 square miles for more detailed and intensive study. On the basis of findings from the current test a tentative well field was laid out and a drilling program devised. One test hole was located on the actual plant site and later developed into a small pilot production well equipped with a deep well turbine pump. Water from this well was used for general construction requirements. Another test hole drilled near the pilot production well and adjacent to the proposed route of the well-collection system was used during the pumping test of the pilot production well to determine the degree of interference. From the data thus obtained, calculations were made to determine the coefficients of transmissibility and storage. Three additional holes

Jan 1, 1955

By Henry N. Toler

Development in the Jackson gas field, Hinds and Rankin counties, for 1935 continued at a slow pace, there being only nine wells drilled on the structure, of which five resulted in gas producers and four in dry holes. There were no wells drilled deep enough during 1935 to test any of the horizons below the producing Selma chalk. There are 113 producing gas wells in the Jackson gas field, with three wells on the southeast edge of the field making some oil with a large quantity of salt water; this oil comes from the same horizon as the gas. The combined open flow of the 113 gas wells is about 4,100,000,000 cu. ft. The proven area of the field is approximately 8000 acres. The production of 10,291,000,000 cu. ft. for 1935 represents the largest yearly pull from the field by almost a billion cubic feet. The total production from the field to date is 45,104,000,-000 cu. ft. It is interesting to note that the rock pressure has dropped from 1010 lb. per sq. in. initial to 943 Ib. at the end of 1935, a decline of only 67 lb. in 6 years. There is a difference of opinion as to the age of the deepest formation tested on the Jackson structure; some people holding that it is Tuscaloosa, others, Trinity, and still others that it is Paleozoic, probably Pottsville. The production of the Amory gas field, Monroe County, continued to decline and the capacity was far under the demand. Originally there were four producing wells in the field with a combined open-flow capacity of approximately 15,000,000 cu. ft. and a rock pressure of 680 lb. per sq. in. At the end of 1935 only two wells were producing with a combined open-flow of less than 1 million cu. ft. and the rock pressure down to 100 lb. or less. No attempt has been made to drill new wells in the immediate field but three wells are being drilled in the county in an effort to secure new supplies of gas. The wildcat operations for 1935, with only 11 wells drilled, were the lowest since 1932, just about one-half the number drilled during 1934. None of the wildcat wells drilled in 1935 resulted in producers and, so far as the writer is aware, did not uncover any large structures. The 11 wells drilled were abandoned or junked at comparatively shallow depths, except the well drilled in George County to 6928 ft. by the United Gas

Jan 1, 1936

By E. W. Wagy

The year 1927 witnessed numerous developments of significance in California. The State's shut-in production increased from an average of 58,000 bbl. daily in January to a maximum of 93,000 bbl. daily in August, and a total of about 25,000,000 bbl. was withheld from the market during the year. This not only lessened the effect of large production at Hunt-ington Beach, Seal Beach and Alamitos Heights, but also was a most effective conservation move. Since 1922, it is estimated that approximately 100,000,000 bbl. of oil that would otherwise have been produced have been held in the ground. I. Outstanding Field Developments of 19271 1. Long Beach Deep Sand. 2. Rincon (Seac1iff)Discovery. 3. Alamitos Heights Discovery. 4. Ventura Avenue Extension. 5. Round Mountain Discovery. 6. Mt. Poso Extension. 7. Potrero (Cypress) Discovery. 8. Buttonwillow Gas Development. 9. Goleta Discovery. 10. Union Avenue, Edison and Fruitvale Areas. (See Fig. 1.) II. Crude Production The most important factor in new crude production in 1927 was the Seal Reach field with its adjacent Alamitos Heights townlot area. Production increased from about 10,000 bbl. daily in January, to a peak of 66,000 bbl. in June. Huntington Beach finished the year 1926 with a production of 102,000 bbl. daily, which declined to 60,000 bbl. by the end of 1927. Due to production in these three areas and the tempering effect of shutting in numerous wells, the California production curve for 1927 was held at a fairly even level. Fig. 2, shows the State's production in 1927 and 1926 as compared with 1923, which was the year of excessive

Jan 1, 1928

This brief resume of events, transpiring in Mexico, culled front the daily New York newspapers, since the last Bulletin-went to press, does not indicate any degree of improvement in the situation. RECORDS OF 217 MEXICO KILLINGS SUBMITTED BY AMBASSADOR FLETCHER Henry P. Fletcher, the American Ambassador to Mexico, called as the first witness before the Rules Committee of the House which has begun a preliminary inquiry into conditions in Mexico, which, it, is believed, will lead to a thorough and far-reaching investigation by a joint Senate and House Committee of the entire Mexican problem, submitted a list of the names of Americans officially known to have been killed in Mexico, a majority of them murdered in cold blood, since the overthrow of Porfirio Diaz by Maderoin 1911. The list contains 217 names and in comparatively few instances do the records show that arrests were made by the particular Mexican faction that happened to be in power where the crime was committed. In only one instance, that of John B. McManus, who was killed in March, 1915, was reparation made. It is significant that McManus was killed by Zapatistas, and Zapata officials apologized for the crime and paid to Mrs. McManus a voluntary indemnity of $20,000 in gold. Of the 217 persons listed as victims of the Mexicans, .137 perished since Carranza came into power. The list, it was admitted, is not complete. It was evident, says the New York Times, that the Ambassador considered the situation very serious.

Jan 9, 1919

By C. B. Jordan

LAVES and Wallbaum' have described TiRu and TiOs as having the same structure as TiFe; they had previously described the latter compound as having the CsCl structure. On the other hand, a careful investigation of the structure of TiFe by Duwez and Taylor- ailed to reveal the ordered CsCl structure, finding instead a random arrangement of titanium and iron atoms on the points of a body-centered-cubic space lattice. Consequently, it is not clear whether Laves and Wallbaum proposed the ordered or the disordered structure for TiRu and TiOs. In order to settle this question as to the structural type and to obtain values of the lattice para- meters (thereby completely determining the structures), the present investigation was undertaken. Samples having the compositions TiRu and TiOs were weighed out accurately from iodide titanium supplied by the New Jersey Zinc Co., ruthenium powder from Goldsmith Brothers Smelting & Refining Co., and osmium powder from Wildberg Brothers Smelting & Refining Co. No analysis was made of any of these metals. According to the respective analyses of the suppliers, total impurities amount to less than 0.03 pct in the titanium and to less than 0.5 pct in the osmium. The purity of the ruthenium is not known. The alloys were prepared by arc melting in a furnace of the type described by Schramm, Gordon, and Kaufmann.9 pecimens for X-ray diffraction were obtained by crushing the ingots and passing the resulting powders through a 200 mesh screen. Diffraction patterns were made with a powder

Jan 1, 1956

By Walter F. Pond, Kendall E. Born

Production of crude oil in Tennessee during 1935 approximated 20,000 bbl., an increase of about 5000 bbl. over 1934. The total production for the state is an estimate, since the only definite figures available are those for Scott and Morgan counties, where 12,377 bbl. were marketed during 1935, an increase of 4305 bbl. over the preceding year. The oil fields of Scott and Morgan counties are near the eastern margin of the Cumberland Plateau where Pennsylvanian sediments rest uncon-formably upon the Mississippian. Near Glenmary, in Scott County, the production is from the middle Mississippian, probably near the top of the St. Louis limestone. Accumulation is due to a low, east-west anticline which has been cut by a fault. This field is now 20 years old and only a few wells are pumped at present. Oil was Struck along Boone Camp Creek in Morgan County in 1924 and there has been small production since that time. The oil comes from the middle of the Fort Payne formation of lower Mississippian age at a depth of 1400 ft. Geologic work in the area has shown that a terrace and porosity conditions in the Fort Payne formation account for the accumulation. The production figures on a number of small producing wells in Clay and Overton counties are not available. As pointed out by Glenn1, the installation of small local skimming or topping plants in the fields has curtailed the shipment of crude oil out of the state and as a result it has been impossible to secure accurate production figures in these counties. The operators, in most cases, are reluctant to give information, and there is no state law requiring them to do so. Based upon information available to the writers, it is believed that between 7000 and 8000 bbl. is a fair estimate of the production in Clay and Overton counties during 1935. More than 500 wells have been drilled in Clay County, the majority of which were drilled east of Cumberland River. Some eight small oil fields have been developed in the county within the past 12 years, a

Jan 1, 1936

By Kendall E. Born, Walter F. Pond

Production of crude oil in Tennessee during 1935 approximated 20,000 bbl., an increase of about 5000 bbl. over 1934. The total production for the state is an estimate, since the only definite figures available are those for Scott and Morgan counties, where 12,377 bbl. were marketed during 1935, an increase of 4305 bbl. over the preceding year. The oil fields of Scott and Morgan counties are near the eastern margin of the Cumberland Plateau where Pennsylvanian sediments rest uncon-formably upon the Mississippian. Near Glenmary, in Scott County, the production is from the middle Mississippian, probably near the top of the St. Louis limestone. Accumulation is due to a low, east-west anticline which has been cut by a fault. This field is now 20 years old and only a few wells are pumped at present. Oil was Struck along Boone Camp Creek in Morgan County in 1924 and there has been small production since that time. The oil comes from the middle of the Fort Payne formation of lower Mississippian age at a depth of 1400 ft. Geologic work in the area has shown that a terrace and porosity conditions in the Fort Payne formation account for the accumulation. The production figures on a number of small producing wells in Clay and Overton counties are not available. As pointed out by Glenn1, the installation of small local skimming or topping plants in the fields has curtailed the shipment of crude oil out of the state and as a result it has been impossible to secure accurate production figures in these counties. The operators, in most cases, are reluctant to give information, and there is no state law requiring them to do so. Based upon information available to the writers, it is believed that between 7000 and 8000 bbl. is a fair estimate of the production in Clay and Overton counties during 1935. More than 500 wells have been drilled in Clay County, the majority of which were drilled east of Cumberland River. Some eight small oil fields have been developed in the county within the past 12 years, a

Jan 1, 1936

By R. S. Shrode

By now most readers of this column are aware that it no longer has a regular editor. Tom Murphy, who did the job so well, has had to bow out because of his duties in Australia---duties that keep him from the luxuries of such things as typists and typewriters for rather extended periods of time. We will miss his regular contributions but hope and expect to hear from him as a guest columnist from time to time. Finding an editor to function on a regular basis turns out to be no simple task. This does not mean that there may not be candidates around who would secretly enjoy having their arm twisted into a "yes" position, but at the moment none has been found. Anyway, at the Salt Lake City business meeting it was agreed that we should try to spread the load around. To that end, the Regional Vice Chairmen were specifically singled out as one potential source of contributions. These fellows should have an opportunity for a hearing during their term in office. The existing organizational set-up of the IndMD Division may be a little unfair to this group of officers. The limited responsibility outlined in our Manual of Official Duties and Responsibilities does not offer them much chance for self-expression. Probably the by-laws were written so as to have a geographic representation of membership in case it should be needed at some time. But that is another subject. The point is that now these regional officers have an opportunity to speak out on topics of their own choosing through this column. Some have already done just that. There are also other potential contributors to the column. One is the Secretary, who twice a year uses the column for distributing the minutes of our business meeting to the members. Another is the outgoing Division Chairman. In Salt Lake City, it was decided that this officer should be challenged to contribute something each year as a means of reviewing events of the past year or explaining what should have happened but didn't. I am, therefore, trying to accept that challenge.

Jan 1, 1970

By V. K. Karra, A. J. Magerowski

An overview of the scope of a computer program meant for aiding the design of crushing circuits is presented. Effect of circuit variables like the screen separation size and the crusher setting is illustrated. For a better understanding of the logic behind the circuit sizing, a detailed commentary in the case of a starting example is given.

Jan 1, 1982

By Gordon G. Bentle, W. P. Fishel

GREINER, Marsh, and Stoughton1 have reviewed the literature in a monograph on the iron-silicon system. The lack of agreement among the various studies may be due to the difference in the purity of materials in some cases. The results of the X-ray method indicate only a general rather than a specific limit of the y loop. The iron-titanium system was investigated by Roe and Fishel,' whose results are used in determining the iron-silicon-titanium y loop. The literature indicates that no study has been made thus far of the iron-silicon-titanium system in the y loop region. Experimental Procedure The alloys were made from Armco iron, 99.86 pct Si, and 98.5 pct Ti. The titanium contains 1.07 pct Fe. The Armco iron contains 0.01 pct C, 0.005 pct Si, 0.02 pct Mn, 0.006 pct P, 0.01 pct S, and 0.04 pct Cu. A dilatation sample of Armco iron was prepared in the same manner as were the other samples. Several dilatation runs indicated that Ac3 begins at 905°C and ends at 910°C, which compares favorably with the study of Wells, Ackley, and Mehl' employing specially purified iron. All alloys were melted in an induction furnace in Alundum crucibles and were top poured into baked core sand molds. The ingots weighed about 600 g as cast. Dilatation samples of 4 in. by % in. diam were taken from the bottom end of the ingot, from which turnings for analysis were taken. Turnings from each end of two of the samples indicated that the alloys possessed uniform silicon content. A hole was drilled halfway through each end of a 4 in, dilatation sample. A chromel-alumel thermocouple was inserted in each hole and the surrounding metal peened in to hold the thermocouple in place. Fig. 1 represents the dilatation apparatus. The heating unit is an Alundum tube wound with resistance wire; the dilatation tube is a McDanel combustion tube; the push rod is zircon; the dial gage is graduated in 0.0001 in. and was vibrated to prevent sticking. A blank run over the temperature range of interest gave no significant dilatation. The thermocouples were attached to a multiple recording micromax which indicated the temperature at each end of the sample at 35 sec intervals. A Lindberg control unit governed the rate of heating of the furnace, and lowering or raising the

Jan 1, 1957

By David G. Chedgy

The Meadow River No. 1 preparation plant, owned by Sewell Coal Co. which is a subsidiary of the Pittston Co., was commissioned in the spring of 1974. A survey of the environmental noise levels was conducted, and the dominant noise sources identified. An engineering program was initiated to reduce the prevailing levels to a point that the operator's exposure would be within compliance with the MESA regulation for ear protection. The program was continued until compliance was achieved and the attenuation factors for each abatement device recorded. The highlights of this program will be presented with a discussion of the practicality of the devices utilized.

Jan 1, 1977

By Allan D. Taylor, Robert S. Shoemaker

Adopting as a principle the phrase "the mill of yesterday should not be built with the high cost money of today," the authors have designed a hypothetical concentrator which could be built for a typical southwestern United States (or other similar area) copper ore. Many of the design features could also be used for other ores in other climates. Functional design, large equipment, and outdoor type of construction have been combined in a concentrator (which includes all ancilliary facilities such as truck and maintenance shops, offices, warehouse, nominal tailings disposal, and water supply) which could be built today for substantially less than the cost of comparable but conventional plants.

Jan 1, 1973

By Maurice B. Dusseault, Edo Nyland

Numerous consistent seismic signals are being generated in a pilot fireflood in a 750 m deep high permeability unconsolidated channel sand in Eastern Alberta. The pilot has a central air injection well, eight production wells on artificial lift, and two internally placed observation wells. Surface seismometers and a 12-hydrophone downhole string were deployed to detect seismics signals. Date were collected for 22 hours employing signal-triggered event detectors recording on cassette tapes. Monitoring during twelve hours of steady air injection at 625m3/s yielded a clear event frequency of about 50 events/h. The events were mostly clear compressional wave arrivals originating in the vicinity of the firefront. Stopping air injection caused a gradual drop in event frequency, and the rate was reestablished when air injection was reinitiated. Spectral frequency analysis and knowledge of material properties indicate that the events are shears of a stick-slip nature associated with the strain-weakening behavior of the over-compacted reservoir sands. The event amplitude indicates small-scale shearing, and different amplitudes suggest that planes re-shear with lower energy release levels. The triggering mechanism for shear rupture is high shear stress created by thermal expansion in the area of highest ther- mal gradient. Other enhanced recovery techniques may also produce useful signals for process control. In particular, steam flooding, hydraulic fracturing, and high-pressure injection operations likely generate mappable microseismic events which can be applied directly to production/ injection strategy.

Jan 1, 1982

By F. D. Weeks

The Salida smelting plant, owned by the Ohio & Colorado Smelting & Refining Co., is situated at an altitude of 7,000 ft., about 2 miles west of Salida, Colo., and 215 miles southwest of Denver. Salida is a division point on the Denver & Rio Grande R. R. where the narrow-gage line serving the San Juan region joins the through standard gage. This narrow-gage road also serves the coal and coke companies at Crested Butte and the lime quarries and mines at Monarch and Garfield, which are only 20 miles distant. These facts, together with the possibility of an appropriate site, doubtless influenced the builders to locate at this point. The smelting plant and yard occupy 80 acres of land on the northeast side of the Arkansas River. The slope of the ground is such as to permit of the ore being delivered by cars at a point 25 ft. above the feed floor; and in front of the furnaces there is a fall of 50 ft. for the slag dump. A recent purchase of river bottom has provided slag room for 20 years. As originally constructed, the plant consisted of four blast furnaces, 40 by 144 in. at tuyéres, two copper-matting furnaces, dust chamber, stack, power plant, blowers, sampling works, and one railroad trestle about 16 ft. from bed floor to rails. Later 12 hand roasters of excellent design were added and the practice of smelting leady matte in a copper-matting furnace was abandoned. Since the plant passed under the present management the equipment has been increased so that the following is a brief description of the same at this date: Two lead blast furnaces, 48 by 180 in. at tuyéres, 17 ft. 6 in. tuyéres to feed floor; four lead blast furnaces, 40 by 144 in. at tuyéres, 17 ft. 6 in. tuyéree to feed floor; two copper-matting furnaces, not used; blast-furnace flue, 900 ft.; area 245 sq. ft.; blast-furnace stack, 150 ft.; above furnace floor, 190 ft. When smelting a 500-ton charge per day, the gases approximate 63,700 cu. ft. per minute and travel at a speed of 260 ft. per minute. The slag is hauled by a 10-ton electric locomotive; the slag shells and settler refuse are elevated to a bin on the feed floor by an electric hoist. The matte is tapped in 1,600-lb. cakes and loaded into cars

Jan 1, 1916

By D. F. Haley

The molybdenite deposits at Climax, Colo., have recently attracted considerable notice, because of their great size, as compared with other known deposits of the same mineral. Climax station, on the Colorado Southern narrow-gage railway, was at one time the Fremont Pass station on the Denver & Rio Grande. It is 141/2 miles northeast of Leadville, and exactly on the divide between the headwaters of the Arkansas and Blue Rivers. Climax station is 11,300 ft. (3444 m.) above sea level. The working tunnel of the molybdenum mine is about 1 mile from the railroad, and 900 ft. above it, at an elevation of 12,200 feet. The climatic conditions are severe, and snow can be expected during any month of the year. Winter sets in not later than Nov. 1, the snowfall is very heavy, and the ground remains covered with snow until June 1, and sometimes even later. From June 1 to Oct. 1, there is much rain and a little snow falls in the late afternoon nearly every day. In October, 1917, there was one of the biggest snowstorms and blizzards of the year. Being just on the divide, constant strong winds blow the fine, dry snow with such force that, during most of the winter, outside work of any kind is accomplished under most trying conditions. Within a few miles of Climax, some of the richest gold placers of Colorado occur. One of them, McNulty Gulch, was just across on the northeastern flank of Bartlett mountain. This mountain, therefore, was well prospected, and the presence of a bluish mineral and a yellowish one resembling sulfur was known to the old prospectors. They thought for many years that the blue mineral was graphite, and it is difficult to say when it first became definitely known that it was molybdenite. Claims had been staked as early as 1896, but it is evident that the prospectors at that time were looking for gold. In 1902, several claims were acquired by H. Leal, who drove a tunnel about 900 ft. (274 m.) long, probably to intersect a fault, which shows on the surface, and was thought to be a possible gold carrier. Gold was not found in paying quantities, but throughout its length the tunnel passed through a fractured silicified granite, showing a fairly uniform distribution of a fine-grained bluish mineral, which was finally determined as molybdenite. For several

Jan 1, 1920

By Nathaniel Arbiter

In attempting to assess the contributions of Antoine Gaudin to the profession which he illuminated for almost a half-century, we will need to examine a very broad canvas. He was active in three significant areas: as a teacher; in research, both through his own endeavors and those of his students; and as a consultant to the mining industry and to the Government. Beyond these specific contributions, there was the major personal influence he had on scores of students, friends, and colleagues in the profession. If a single measure of the man's contribution is to be found, it will be the extent and direction in which he influenced the practice of his profession. To find this we should examine the state of miner- al processing when he began his activities in the 19201s, the progress which has taken place over the past half-century, and the part his activities played in this advance. However, there is a provocative and broader examination which I have chosen to make instead. This is to examine the past century in mineral processing through the lives of three men who, by common agreement, stand on the heights, both in teaching and in their contributions to industry: Robert H. Richards, Arthur F. Taggart, and the man whose memory we honor this evening, Antoine M. Gaudin. Their careers, by coincidence, cover just a century. This is also AIME's first century, and the first century of mineral industry education in the United States. In fact, mineral processing itself on any significant scale in the country encompasses only a century and a quarter. BEGINNINGS OF PRACTICE IN THE U.S. Before the 1840’s, U.S. mining, except for coal and iron ore, was on a small scale and was confined to the eastern states, with processing practically nonexistent. The 1840's saw the beginning of Michigan native copper production, including ore dressing; the 1850’s, iron ore production in Minnesota; and the 1860’s, lead production and processing in Missouri. But the most explosive event was the California gold rush after 1848, which not only brought tens-of-thousands of fortune hunters to the West, but also catalyzed broad mining activities and processing within the following decades. This was not only in California but, after the first fever of the gold rush subsided there,

Jan 1, 1976

By D. F. Haley

THE molybdenite deposits at Climax, Cool., have recently attracted considerable notice, because of their great size, as compared with other known deposits of the same mineral. Climax station, on the. Colorado Southern narrow-gage railway, was at one time the Fremont Pass station on the Denver & Rio Grande. It is 1412 miles northeast of Leadville, and exactly on the divide between the headwaters of the Arkansas and Blue Rivers. Climax station is 11,300 ft. (3444 m.) above sea level. The working tunnel of the molybdenum mine is about 1 mile from the railroad, and 900 ft. above it, at an elevation of 12,200 feet. The climatic conditions are severe, and snow can be expected during any month of the year. Winter sets in not later than Nov. 1, the snowfall is very heavy, and the ground remains covered with snow until June 1, and sometimes even later. From June 1 to Oct. 1, there is much rain and a little snow falls in the late afternoon nearly every day. In October, 1917, there was one of the biggest snowstorms and blizzards of the year. Being just on the divide, constant strong winds blow the fine, dry snow with such force that, during most of the winter, outside work of any kind -is accomplished under most trying conditions. Within a few miles of Climax, some of the richest gold placers of Colorado occur. One of them, McNulty Gulch, was just across on the northeastern flank of Bartlett mountain. This mountain, therefore; was well prospected, and the presence of a bluish mineral and a yellowish one resembling sulphur was known to the old prospectors. They thought for many years that the blue mineral was graphite, and it is difficult to say when it first became definitely known that it was molybdenite. Claims had been staked as .early as 1896, but it is evident that the prospectors at that time were looking for gold. In 1902; several claims were acquired by H. Leal, who drove a tunnel about 900 ft. (274 in.) long, probably to intersect a fault, which shows on the surface, and was thought to be a possible gold carrier. Gold was not found in paying quantities, but throughout its length the tunnel passed through a fractured silicified granite, showing a fairly uniform distribution of a fine-grained bluish mineral, which was finally determined as molybdenite. For several

Jan 8, 1918

OUTSTANDING symbol of the machine age, the steam shovel needs no introduction. Few individuals there are, in the United States at least, that have not watched with fascination the almost human motion, the more than human strength, the rhythm of the whole steam-shovel cycle of crowding, digging, swinging, dumping, swinging, and crowding again. A mass of steel with some copper and other metals, fed with water and coal, guided by a single alert and dexterous operator, or perhaps two, does the work that would require 50 to 500 men or even more. The largest shovels working in the copper mines have loaded into waiting railway cars as much as 10,000 tons of ore in a single 8-hour shift. With no equipment but hand shovels, it would, in fact, be impossible to duplicate the work with any number of men; first, because they would be in each other's way, and second, because the steam shovel can lift single pieces of rock weighing 5 or 10 tons with effortless ease. Of recent years, internal-combustion engines and electric motors have displaced steam as a motive power in many instances; and of course the detailed design of the shovels has been improved immensely. Whereas the largest dippers used 30 years ago had a capacity of 3 ½ to 4 cu. yd., today the 350-ton shovel used at Chino has an 8-yd. dipper, as has the 320-ton shovel at Chuquicamata. Incidentally, for stripping at coal mines a shovel having an 18-yd. dipper is in use. However, the principle of operation of the modern shovel, regardless of the size and type of motive power, is essentially the same as that of the earlier shovels. It is fair to say that the indispensable of open-cut mining is the steam shovel, or, to be more precise, if perhaps less picturesque, the power shovel. Somehow the electric shovel seems to lack the glamour that

Jan 1, 1933

By Robert Pring

IN addition to the humanitarian aspects of a dust-control program, certain economic benefits are becoming more fully recognized and now furnish a greater incentive to the mill operator to eliminate the dust from his plant. It is well known that a favorable working environment promotes increased efficiency and improves the morale of em-ployees, with a consequent decrease in labor turnover rates. One progressive mining company estimates its direct and indirect labor turnover costs at from $40 to $50 per man; for skilled labor, such as machine operators, the cost may approach $100 per man. While these figures may not be typical of every plant, they do indicate a potential savings in operating costs. Dust signifies waste; its elimination de-creases maintenance costs of mechanical and electrical equipment; its recovery is often justified from the standpoint of values contained in the collected material, although in large-scale milling operations handling low-grade ore this may not be an important factor. Perhaps the most significant trend in industrial sanitation is that dust-control equipment and procedures are becoming recognized as integral parts of the mill flow-sheet. Exhaust ventilating systems are now afforded equal care in design and mainte-nance to that given other machinery more closely related to the process,

Jan 1, 1940