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By Ray W. Ballmer, K. H. Matheson

Since start-up in 1906, Bingham had been a rail pit, beginning with steam locomotives and converting to electric locomotives in 1923. Ore production was maintained by effective utilization of avail- able rail equipment. From time to time, as it became necessary to deepen the pit and as stripping ratios increased, studies of alternative material haulage systems such as diesel locomotives, conveyor belts and trucks were made. Conversion from rail haulage with electric locomotives could not, however, be justified. Because of a gradual decline in ore grade, a program was approved in 1963 to raise ore production to 108,000 tpd. The decision posed a serious problem: due to built-in inflexibility and other limitations, a parallel expansion of the rail haulage system was impractical. (Track and trolley wire relocation causes greater shovel downtime than required for normal maintenance; instability of the dumps and the resulting additional track maintenance increases greatly as the daily volume of waste material increases.) Studies indicated that economically the most favorable course of action would be the replacement of rail haulage on the upper levels of the mine by truck haulage.

Jan 11, 1965

By Robert U. King

The Climax Molybdenum Company's mine is situated on the Continental Divide at Fremont Pass in Lake County, Colorado. Elevations at the mine range from 11,000 it. to over 12,000 ft. The ore body is on the south flank of Bartlett Mountain, a prominent peak in the Ten Mile Range. A horizontal section of the mine, such as the Phillipson level (Fig. I), shows the outer ore zone as an annular ring varying in width from 300 to 800 ft., surrounding barren silicified rock. In vertical section the outer ore zone is dome shaped (Figs. 2 and 3), the apex of which is truncated at the surface by glaciation, exposing part of the ore body. The outer ore zone overlies the barren core and is itself overlain on the flanks of the dome with unmineralized rock. An ore zone of similar shape underlies the barren core of silicified rock, known as the Central Ore Zone (Figs. 2 and 3). Molybdenite is distributed uniformly through a zone of moderately silicified granite, schist and quartz monzonite (early) porphyry, around a highly silicified core. The molybdenite occurs in veinlets associated with fine granular quartz and pyrite, replacing altered and fractured granite, schist, and porphyry, and as coatings on numerous fractures cutting these rocks. Intense fracturing of all rocks is a characteristic feature of the Climax ore body. Most fractures are mineralized and no longer represent planes of weakness. Much fracturing is postmineral, however, and these fractures are generally filled with sericite or gouge, or remain as unmineralized joints separating otherwise massive rock into blocks of various size. Study and Mapping of Caving Characteristics Important differences in the behavior of caving of various blocks of ore at Climax have been recognized, involving arching of the rock over caved stopes, tendency of caved rocks to funnel, and size of caved rocks. Also, new problems have arisen associated with future mining on the Phillipson level, and may occur with proposed development of lower levels, such as excessive stress on mine pillars caused by large masses of overlying stable rock, and higher costs in maintenance of mine workings in soft, weak rock. To explain the differences and to provide solution for these problems, a study of geologic structure was undertaken early in 1944, to determine whether it would be possible to map cavability of rock from physical features exposed in mine workings and in diamond-drill cores. A comparison of known caved areas was made and rocks were classified structurally according to strength or degree of cavabil-ity. As nothing of this nature had been done before at Climax, the approach to the problem was rather indefinite. Several trials were made with negative results, but collectively indicated a suitable method. This was to examine all mine workings and diamond-drill cores, record-

Jan 1, 1946

New Products Equipment

Jan 6, 1953

By Oscar H. Hershey

COMPLAINT has been made that in the literature of economic geology the work of the "company or practical" mining geologists does not get enough attention. I propose to attempt to overcome this com¬plaint in reference to one important lead-mining district, that of the Coeur d'Alene in northern Idaho. Furthermore, I will assume that the reader is not so much interested in the geology of the district as in the methods of application used and incidents that have arisen in the work. All the important discoveries of ore in the Coeur d'Alene were made without benefit of geology. Certainly I would not claim the reputed discoverer of the Bunker Hill mine as a fellow geologist. It appears also that the mines were operated quite successfully for many years without geological specialists, though doubtless certain properties were visited at long intervals by such men as Waldemar Lindgren. It was known that the ores occur in quartzite, graywackes and slates as stated by J. R. Finlay in 1903. (TRANS., VOL. 33.) He described the ore as occurring in typical fissure veins that occupy fault-planes of indeterminate displacement. The Bunker Hill lode was based on a definite fissure with the mineralization all on the hanging-wall side, extending as far as 300 ft. from the fissure.

Jan 1, 1933

By Leonard P. Skolnick

PROPERTIES of materials containing a hard con-stituent dispersed in a metallic matrix are dependent on the distribution of the hard phase.'-' The grain growth of titanium carbide in liquid nickel was studied in order to understand microstructural development in this and similar systems. Smith" has examined the influence of surface energy on the distribution of phases in alloys. The grain growth of tungsten carbide in cobalt has been the subject of many conflicting theories. Those prior to 1950 have been summarized by Goetzel.' Recently, Gurland and Norton3 and Gurland8 have indicated that growth occurs primarily by diffusion through the liquid phase in order to lower the inter-facial energy between the carbide and the liquid metal. In the development of the Ti-C-Ni ternary phase diagram, Stover and Wulff9 have shown that both eutectiferous dendritic titanium carbide, and primary titanium carbide which had developed crystals of cubic symmetry, were rounded by heating below the solidus, and that if primary carbide was already present the typical eutectic decomposition products were not formed. Experimental Procedure The infiltration technique was used to study the grain growth of titanium carbide in nickel. In contrast to sintering, infiltration more readily assures uniform dispersion of the two phases, and the problems associated with mixing by milling; i.e., mill contamination, breakdown of original carbide size in the operation, development of interfering surface films, etc., are avoided. In addition, the complicating effect of densification by shrinkage is eliminated. The titanium carbides used were commercial grades. Their chemical analyses, size distributions and shapes are summarized in Table I. Size analysis was conducted by microscopic count on a minimum

Jan 1, 1958

EDWIN M. CHANCE (communication to the Secretary?).-The subject of miners' lamps. has long interested me and it would seem that the thought that has been given to it by the Bureau of Mines, and the users

Jan 6, 1917

By Frank R. Milliken

This paper is a running commentary on metallurgical problems and developments, stressing ilmenite flotation, since the start of operations five years ago, at the mill of National Lead Company, Titanium Division, MacIntyre Development, Tahawus, New York. In early 1941, when world conditions threatened to cut off the supply of ilmenite (obtained largely from India) to this country, the National Lead Company started to develop and bring into production their MacIntyre Development. This operation supplied the bulk of the ilmenite used during the war period for the manufacture of the much needed titanium pigments. MacIntyre Development is at Tahawus, New York, on the headwaters of the Hud- son River in the center of the scenic Adirondack Mountains. A general description of the operation was given in the Adirondack Issue of Mining and Metallurgy for November 1943. Operating tonnages and production have increased since 1943, however. Nearly 10,000 tons of.ore and waste is broken and loaded daily in the open-pit mine. About half of this tonnage is ore, from which is produced nearly 800 tons of ilmenite concentrate and 1600 tons of magnetite concentrate daily. Ore—types From an ore-dressing standpoint, there are five rather distinct ore types and two waste-rock types in the mine. The ore types are shown in Table I. The anorthosite waste is a coarse-grained white rock, largely labradorite feldspar. The gabbro waste is generally finer grained, and contains, in addition to feldspar, 35 to 75 pct iron silicates such as hornblende, in garnet and biotite. A minor mineral mineralogically, but important metallurgically, is apatite. A few calcite

Jan 1, 1949

By D. J. Carney, E. C. Rudolphy

Large macroscopic nonmetallic inclusions were related to altered fireclay refractories by chemical and microscopic means. Pouring refractories are discussed as a source of these large inclusions. Nozzles and wells are major contributors. Use of alkali and titania contents as tracers is described. Recommendations are offered to minimize the sources of inclusions from pouring refractories. IN any attempt to improve the cleanliness of plain carbon and alloy steels, consideration must be given not only to the proper deoxidation practice to minimize inclusions, but also to sources of inclusions from pouring refractories. In some cases, the inclusions resulting from deoxidation may be minor in amount, yet a relatively dirty steel may be produced as a result of improper care in the pouring practices for the steel. The number of studies of inclusions resulting from pouring refractories has increased recently and some excellent reports on this subject have already been published.'4 Some of these reports were reviewed briefly in a companion paper by M. P. Fedock.5 Mr. Fedock's contribution is a fine addition to the studies necessary to improve steel cleanliness for the ultimate benefit of all steel producers and consumers. In the interest of constantly improving cleanliness, the authors have been actively engaged for the past two years in experimentation to determine more closely the sources of inclusions in steel. One phase of this work was associated with efforts to define more closely the sources of macroscopic inclusions which have been experienced on occasional heats. The term "macroscopic inclusions" is defined in general as those inclusions which are visible to the naked eye or at low magnifications of the order of less than X25. These inclusions sometimes can be seen in the macro-etch tests of billets and slabs. This report summarizes a few of the field experiments and laboratory studies conducted at the South Works of the United States Steel Corp., which were made regarding nozzles, wells, and ingot scums, as well as inclusions occurring in steel products. The data in the present study, together with the data of Mr. Fedock concerning ladle erosion, should be of value in regard to future studies of inclusions arising from pouring refractories. The knowledge gained as a result of data collected thus far at South Works has been helpful in improving the cleanliness of the products and in pointing the way toward further improvements. Similarity of Large Inclusions to Refractories and Altered Refractories In the routine inspection of billet etch tests, occasional inclusions visible to the naked eye have been observed. These large inclusions most frequently occur near the top of the ingot and near the billet surface. When such material was encountered, careful examinations were made in an attempt to determine the origin of these inclusions. In a relatively few cases, examination revealed that the material was unaltered fireclay refractory of a type similar to that used for hot-top material, with only the surface of the inclusions having an altered appearance under the microscope. However, the great majority of these inclusions were completely altered-refractory material. The term "altered refractory" is defined

Jan 1, 1955

By Thomas A. Wright

No symposium on die casting could be complete without consideration of the methods of formula and impurity control. No consideration of control would be complete without discussion of that new tool of the analytical chemist and inspector, the quartz spectrograph. Just as there is an increased appreciation of the possible applications of the die-casting process and of die castings, so too is there, slowly but surely, of the spectrograph. At present the role of the instrument might well be compared with that of brass or magnesium die castings. Neither is as widely understood or known as they will be. Product specifications are increasing and are getting more explicit and often more rigid. The designer, metallurgist and production engineer or superintendent will be forced to depend more and more on the chemical laboratory. Sampling, as well as analyses, testing and inspection problems will grow. The chemical laboratory must meet its increased responsibility and use of the spectrograph will become more common. Advantages of increased precision, greater speed, lessened labor and often lower costs cannot be ignored. It will be the purpose of this paper in part to outline the respective fields of chemical and spectrographic analyses and to indicate where one may overlap the other and in part to indicate certain possible sources of contamination of zinc-base die-cast alloys in particular. COMPOSITION Aluminum.-Aluminum die castings are expected to conform to the specifications of the American Society for Testing Materials1† and the Society of Automotive Engineers2. The A.S.T.M. has recognized seven

Jan 1, 1935

By Milo W. Krejci

(Butte Meeting, August, 1913.) THE plant and quarries of the Inland d Portland Cement Co.. are located- at Metaline Falls, Wash, about 128 miles north of Spokane, on the Fend Oreille river, and 10 miles, of the Canadian border. The plant is one of a chain of cement plants controlled by the Lehigh Portland Cement Co., of Allentown, Pa. Work on this plant was commenced in June, 1910, and was completed in April, 1911, but on account of some delays in the construction of the power plant, the works were not put into operation until August., 1911. Since then it has been in continuous operation and has furnished the Inland Empire with a high grade of cement. Fig. 1 is a, view and Fig. 2 is a plan of the works. Water Power Development.-The source of the water supply for the hydro-electric plant of the Inland Portland Cement Co. is Sullivan lake, a body of water approximately 5.5 miles long and 0.5 mile wide, situated in the Kanisku Forest Reserve. A wooden crib dam was installed so as to raise the elevation of the lake 25 f and the additional storage capacity was taken up by the diversion of Sullivan creek into the lake by means of a wooden flume, 0.25 mile long, 6 by 8 ft. in crosssection, and a ditch 1,200 ft. long. The water from the lake follows the natural water course to an intermediate storage reservoir, which was created by the construction of an earthen dam. This pond was used in connection with the saw mill which was installed at this point. Besides the earth dam, there was also built a crib, at the point shown in the sketch map, Fig. 3. This crib dam is 35 ft. high. From this point the excess water follows the natural -course of Sullivan creek to the Pend Oreille river.

Jan 7, 1913

By K. E. Brown, A. R. Hagedorn

Continuous, two phase flow tests have been conducted during which four liquids of widely differing viscosities were produced by means of air-lift through 1%-in. tubing in a 1,500-ft. experimental well. The purpose of these tests was to determine the effect of liquid viscosity on two-phase flowing pressure gradients. The experimental test well was equipped with two gas-lift valves and four Maihak electronic pressure transmitters as well as instruments to accurately measure the liquid production, air injection rate, temperatures, and surface pressures. The tests were conducted for liquid flow rates ranging from 30 to 1,680 BID at gas-liquid ratios from 0 to 3,-270 scf/bbl. From these data, accurate pressure-depth traverses have been constructed for a wide range of test conditions. As a result of these tests, it is concluded that viscous effects are negligible for liquid viscosities less than 12 cp, but must be taken into account when the liquid viscosity is greater than this value. A correlation based on the method proposed by Poettmann and Carpenter and extended by Fan-cher and Brown has been developed for 1¼-in. tubing, which accounts for the effects of liquid viscosity where these effects are important. INTRODUCTION Numerous attempts have been made to determine the effect of viscosity in two-phase vertical flow. Previous attempts have all utilized laboratory experimeneal models of relatively short length. One of the initial investigators of viscous effects was Uren1 with later work being done by Moore et al.2,3 and more recently by Ros.4 However, the present investigation represents the fist attempt to study the influence of liquid viscosity on the pressure gradients occurring in two-phase vertical flow through a 1¼-in., 1,500 ft vertical tube. The approach of some authors has been to assume that all vertical two-phase flow occurs in a highly turbulent manner with the result that viscous effects are negligible. This has been a logical approach since most practical oil-well flow problems have liquid flow rates and gas-liquid ratios of such magnitudes that both phases will be in turbulent flow. It has also been noted, however, that in cases where this assumption has been made, serious discrepancies occur when the resulting correlation is applied to low production wells or wells producing very viscous crudes. Both conditions suggest that perhaps viscous effects may be the cause of these discrepancies. In the first case, the increased energy losses may be due to increased slippage between the gas and liquid phases as the liquid viscosity increases. This is contrary to what one might expect from Stokes law of friction,' but the same observations were made by ROS4 who attributed this behavior to the velocity distribution in the liquid as affected by the presence of the pipe wall. In the second case, the increased energy losses may be due to increased friction within the liquid itself as a result of the higher viscosities. The problem of determining the li- quid viscosity at which viscous effects becomes significant is a difficult one. Ros4 has indicated that liquid viscosity has no noticeable effect on the pressure gradient so long as it remains less than 6 cstk. Our tests have shown that viscous effects are practically negligible for liquid viscosities less than approximately 12 cp. Actually there is no single viscosity at which these effects become important. These effects are not only a function of the viscosities of the liquids and of the gas but are also a function of the velocities of the two phases. The velocities in turn are a function of the in situ gas-liquid ratio and liquid flow rate. Furthermore, the role of fluid viscosities in either slippage or friction losses will depend on the mechanism of flow of the gas and liquid, i.e., whether the flow is annular. as a mist, or as bubbles of gas through the liquid. These mechanisms are also a function of the in situ gas-liquid ratios and the flow rates. It would thus seem that the best one could hope for is to determine a transition region wherein the viscous effects may become significant for gas-liquid ratios and liquid production rates normally encountered in the field. The viscous effects might then be neglected for liquid viscosities less than those in the transition region but would have to be taken into account when higher viscosities are encountered. There are numerous instances where crude oils of high viscosity must be produced. The purpose of this study has been to evaluate the effects of liquid viscosities on twephase vertical flow by producing four liquids of widely differing viscosities through a 1 % -in. tube by means of air-lift. The approach used in this study was as follows:

Jan 1, 1965

By H. R. Drullard

TO obtain the best results from hammer drills, close attention must be paid to two factors in drill maintenance, which are of equal importance; one is lubrication, the other is the shank. With the exception of stoping drills, most modern rock drills require both oil and grease. The oil ports are in the lubricator, on or behind the hammer cylinder; the grease port for the lubrication of the chuck sleeve and rotating mechanism is on the chuck end. Ordinary machine oil is not adapted to rock drills; a heavier more gelatinous oil such as castor machine oil or liquid grease should be used. The lubricators should be filled once for every 12 or 14 ft. (3.5 to 4 m.) of hole drilled. Grease guns should be used to fill the port in the chuck end once a shift; a medium (No. 3) grease is well adapted to this purpose. Hard grease must not be put into the lubricators, as it will not flow through that part. Contrary to the popular belief, oiling a machine once or twice a shift does not provide sufficient lubrication; the drills should be oiled once for every 12 or 14 ft. of hole drilled. The rotating handle of a stoping drill is an oil reservoir and is provided with a port for oiling. The rotating handle is packed with wick-ing, or similar material, which causes the oil to feed slowly from the handle to the other parts of the machine. Stoping drills require oil at least twice a shift; lighter oils than castor, such as Arctic Ammonia, may be used. Drills used in shaft sinking can be oiled satisfactorily by placing a good-sized, drop, sight lubricator on the station above the sinking operations and connecting it with the air-line supplying the sinking drills. If this lubricator is properly filled and adjusted, a uniform oiling of the sinking machines will be effected without the necessity of oiling the drills individually. The grease end should be filled at the station or surface before each drilling period. The shift boss should see that the machines are greased and also that the lubricators at the station function properly. The life of the air-drill hose is somewhat shortened by this method, as oil attacks the inner tube; but as some oil is always present in the compressed air, this is not a serious objection to the method.

Jan 1, 1922

By N. Brown, H. Green

The effect of quenching temperature and of aging temperature and time on compression stress-strain curves of ß brass was investigated. Age softening occurs at a rate which decreases with decrease of quenching temperature below the critical temperature for ordering. The activation energy for softening is 15,400 cal per mol. No matter how rapidly brass is quenched or what the temperature from which it is quenched, practically complete order is obtained at room temperature. It has been demonstrated that with respect to the specific heat,',' electrical resistivity," X-ray diffraction, and microstructure, the slowly cooled and rapidly quenched specimens are the same and that complete long range order exists in both cases. However, Smith" showed that the hardness of ß brass depended upon the cooling rate and the temperature from which brass is quenched. Smith showed that the hardness was a maximum for specimens quenched from about 445 °C and that the as-quenched structure softened at room temperature at a rate depending upon the temperature prior to quenching. This softening after quenching is in this paper referred to as age softening. The results of this investigation are qualitatively the same as the findings of Smith. However, a more detailed analysis of these phenomena has been possible since the stress-strain curve offers a more sensitive index of the state of the metal than hardness. It is the purpose of this paper to show how the mechanical properties are related to the ordering of ß brass. A 200-lb ingot made from electrolytic copper and electrolytic zinc was extruded to 1/2in. rod. Chemical analyses at frequent intervals along the rod showed that the alloy contained 51.5 pct Cu with the greatest impurity being iron, at 0.01 to 0.001 pct. To obtain a constant test material, the 1/2in. extruded rod was warm-rolled to % in. diameter at 200°C and then recrystallized to a grain size of 2.0 mm. The specimens for the compression test were % in. high and % in. in diameter. The specimen ends were polished on 600 metallographic paper and coated with Molykote for a lubricant. The compression rig consisted of an anvil resting on the machined table of the Baldwin Southwark testing machine and a plunger fixed to the movable cross

Jan 1, 1954

By Raymond B. Ladoo, C. A. Stokes

T is unfortunate that the word "economics" has -¦¦ come to mean, in the minds of many people, a sort of half-baked mixture of New Deal philosophy and bookkeeping. It may mean anything from mine cost keeping to the theory of gold as a monetary standard. As applied to the industrial mineral industries as a whole it means to us an integrated study of all of the technical, geographical, market, financial, and other factors which determine whether or not a given enterprise has a sound chance of making a business success. Of course it is impossible to generalize too freely in this large group of industries which go to make up the nonmetallic minerals. This group includes such dissimilar products as crushed stone and ca- pacitor mica, phosphate rock and spinning fiber asbestos, roofing granules and potash salts, borate minerals and monumental granite. Yet in many respects their economic problems are similar and, at the same time, far different from those of the metals and of petroleum and coal. These basic differences are almost never recognized by people outside the industries and are rarely appreciated even by metal mining engineers. But in many instances these economic factors are fully as important as, if not more important than, technologic problems. It has been a long fight to get an intelligent and wide-spread appreciation of sound technology in the nonmetallic mineral industries. The importance of the economic side of the problem has yet to be widely understood and appreciated. The problem was outlined in considerable detail by one of the authors some 18 years ago in a long series of articles* and he has since prepared numerous talks

Jan 1, 1951

By Raymond B. Ladoo, C. A. Stokes

T is unfortunate that the word "economics" has -¦¦ come to mean, in the minds of many people, a sort of half-baked mixture of New Deal philosophy and bookkeeping. It may mean anything from mine cost keeping to the theory of gold as a monetary standard. As applied to the industrial mineral industries as a whole it means to us an integrated study of all of the technical, geographical, market, financial, and other factors which determine whether or not a given enterprise has a sound chance of making a business success. Of course it is impossible to generalize too freely in this large group of industries which go to make up the nonmetallic minerals. This group includes such dissimilar products as crushed stone and ca- pacitor mica, phosphate rock and spinning fiber asbestos, roofing granules and potash salts, borate minerals and monumental granite. Yet in many respects their economic problems are similar and, at the same time, far different from those of the metals and of petroleum and coal. These basic differences are almost never recognized by people outside the industries and are rarely appreciated even by metal mining engineers. But in many instances these economic factors are fully as important as, if not more important than, technologic problems. It has been a long fight to get an intelligent and wide-spread appreciation of sound technology in the nonmetallic mineral industries. The importance of the economic side of the problem has yet to be widely understood and appreciated. The problem was outlined in considerable detail by one of the authors some 18 years ago in a long series of articles* and he has since prepared numerous talks

Jan 1, 1951

By George Scott

MANY requests for information as to the possibility of washing coals to some predetermined percentage of ash or sulfur have suggested that the producers aim to satisfy some degree of purity set by the user of the fuel, rather than to attain the greatest economic benefit to all concerned. This paper is written to show that the highest economic purity of washed coal can be determined from washability studies of the raw coal, costs of mining and washing coal, and data on the effect of ash and sulphur on the value of the coal for the particular use for which it is intended. COKE FOR BLAST-FURNACE USE For purposes of illustration, we take the case of coal washed for coke to be used in the iron blast furnace. The method outlined can be made general in its application by substituting for the figures used here the actual operating figures for the particular case under consideration. In general, it costs the blast-furnace operation from 8 to 25 c. per ton of pig iron to slag out each 1 per cent. of ash introduced into the blast furnace by the coke. This figure depends on which one per cent. of ash is removed, and decreases with decrease in ash: When blast furnaces and coal mines are considered as a whole, the figure decreases to zero and then becomes negative, on account of low recovery of washed coal. Various figures1 have been given by different investigators: These figures necessarily differ, not only on account of the differences in operating costs but on account of the difference in the respective fuels as well. For the purpose of this paper, which, as explained, is to point out a method of attacking a certain problem, the figures used in the exposition of the method are of secondary importance. It is apparent that no universally applicable figures can be used, because there are none. Each plant has its own coal,2 its own operating cost, and its own conditions.

Jan 1, 1929

By C. R. Hayward, H. O. Hofman

I. INTRODUCTION. THE aim of instruction in a metallurgical laboratory is to make real the principles on which metallurgical processes and operations are based, and to foster the spirit of investigation: The materials with which experiments are carried out are ores, metals, and metallic compounds. The method varies with the end sought. A class may work as a whole, each member contributing his share to the solution of a problem, or the students may carry on investigations independently; the former exemplifies class-research; the latter, individual research. It is with a branch of the former, with special reference to ore-treatment that the present paper intends to deal. In smelting an ore by a well-established process, the result is shown by analyzing the products to see whether their compositions correspond to those calculated in making up the charge; by taking account of stock to show the distribution of metal in the different products made and the losses from dust and volatilization, by casting a thermal balance to find the ,distribution and losses of heat; and by making a cost-sheet to ascertain, as far as possible, the necessary outlay of money. In, lixiviation and amalgamation, the mode of operating has to be varied to adapt a process to the individual ore. Here a number of tests become necessary. Each will consist of a series of experiments with one variable, in order to find the conditions under which the variable gives the best result; a. summary of several tests will give the best method of operating.. Working a number of charges with the best method will furnish the data desired for ascertaining the recovery of metal,

Jun 1, 1909

By N. S. Keith

This question is suggested by a statement made by Dr. Siemens, widely printed in the journals of the day, that a continuous rod of copper, thirty miles in length and three inches in diameter, is capable of conveying that distance, electrically, energy equal to 1000 horse-power. It is not attempted to advance the statement that the source of power shall be zinc, nor even coal, but waterfalls, which from their situation are not practically available for manufacturing establishments in their immediate vicinity. In order to fully consider this subject,, we must understand the doctrine, I may say the science, of the correlation of the forces, so called. We must understand that all matter is endowed with an amount of force, and that each atom and molecule, simple and compound, has its specific portion of the whole. This force, at rest, is called latent heat, intrinsic energy, or potential. In motion it is called heat, light, electricity, chemical affinity, attraction, magnetism, power, etc., according to its sensible manifestations. These are the effects of the one force active in different substances, or in different assemblages of matter. Force put in motion comes to rest by reason of the resistance to motion which it eucounters; in overcoming

Jan 1, 1879

By Edgar L. Newhouse

The lead smeltery at East Helena, Mont., controlled by the American Smelting & Refining Co. since 1899, has been in continuous operation for the past 25 years. Most of the old smelting and roasting practices have been superseded by newer and more modern methods, but on account of the difficulties involved in changing the original construction, some of the methods in use of handling materials are not the most modern. This plant, however, is particularly interesting as being one of the few essentially lead smelteries in the United States. At Federal, Ill., Collins-ville, Herculaneum, and possibly other places, similar work is being done, but it is doubtful whether any of them produces as much lead as the East Helena plant, whose monthly production averages 6,500 tons. The situation, 5 miles east of Helena, is convenient to both the Great Northern and Northern Pacific railroads, while the electric power is obtained from Canyon Ferry, 12 miles east on the Missouri river. Local quarries supply the requisite amount of lime rock, which the contracts require to be crushed to 5 in. Of the 450 men on the monthly pay roll, a census showed 200 Austrians, 110 Americans, and 30 Italians, the balance being made up of miscellaneous nationalities. The ore supply is mainly derived from the Coeur d'Alene mines in Idaho, and consists of crude ore, coarse and fine concentrates, middlings, and slimes. About one-half of the total output of the Coeur d'Alene camp is sent to East Helena. An average analysis of these ores gives approximately 40 per cent. lead and 11 per cent. sulphur. Local shipments, varying from month to month, are mostly highly siliceous gold and silver ores carrying little lead. Small shippers, leasers of old mines, and prospectors are very numerous throughout Montana, and it is the policy of the company to encourage these men by every possible means, including the free sampling and analysis of their ores and aid in the development of their mines and prospects, whenever their results show promise.

Jan 1, 1915

By Thomas S. Lovering

Hot springs, geysers, steam-emanating fumaroles- these creatures of nature were until recently little more than geological curiosities, but today they are exciting the interest of engineers around the world for it has been shown that such hyperthermal areas can be profitably harnessed by man to provide heat and power for his communities. Although water from hot springs was used centuries ago to heat some Korean dwellings, is being used today by one-third of Iceland's population for similar purposes, and is finding industrial applications in New Zealand and elsewhere, the most dramatic use of geothermal energy has been its conversion into electricity. The largest installation at the present time is that at Larderello, Italy, where the Count of Larderello began to experiment in the production of electricity from geothermal steam in 1904. Eight years later after a quarrel with the local power company, the Count installed his first steam turbine, a unit of 250 kw capacity.

Jan 9, 1965