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By W. H. Bassett

THE subject assigned is rather a broad one but it, is doubtless expected that it will be dealt with as applying to metals and alloys and not to the ob-taining of metals from their ores. The liberty will further be taken of confining the matter discussed to copper and some of the copper alloys. Everyone is familiar with copper, at least everyone who attends the meetings of the A. I. M. E., so no gen-eral description of the metal is necessary. There are still to be recognized two classes of copper and each of these has some sub-divisions. The two general classes are electrolytic and fire-refined copper. Since there is some misunderstanding about these materials, definitions are in order. Electrolytic is just what the name implies. It may and it should be very pure but with high current densi-ties or very impure anodes, or both, impurities such as antimony, tellurium and lead may be carried over to the, cathode. Any one of these, or a combination in which they occur, are alike fatal to good working quali-ties in the resulting metal. Of course, these metals are not supposed to be deposited with copper, but slimes containing them may be 'occluded. in the deposited cop-per or held in rough cathodes if not washed with suffi-cient thoroughness.

Jan 5, 1927

By Jack Haptonstall

INTRODUCTION The mines of western central Mexico historically contributed a profusion of gold and silver for the treasury of Spain and later provided sources for financing the Mexican War for Independence and the Mexican Revolution. The western coastal and barranca (cliff) tribes were hunters and extremely hostile, and the Spaniards were not able to penetrate many of the rich districts of their rugged homeland until the mid-1700's. This was more than 200 years after Cortez began the Inquisition by defeating the Aztecs and their allies in a decisive battle in the great city of Tenochtitlan (present day Mexico City). The Spaniards had a voracious appetite for silver and gold, and it was inevitable that they would finally subdue the natives and commence mining activities. Described in this paper are some of the precious metal mining activities in the southern half of the State of Sinaloa and the western half of the State of Durango (Figure l), and specifically those mining activities in the area controlled by the company with which the author was associated for 14 years, Minas de San Luis, S. A. de C. V., the parent company of which is now Industrias Luis Min, S. A. GENERAL DESCRIPTION Geography, Logistics and Climate The most spectacular of the physiographic provinces, the western Sierra Madre Occidental is the cliff or "barranca" province, the

Jan 1, 1983

As a result of Engineering Council's request to the Director of the Census, the National Service Committee has been successful in effecting a reclassification of engineers so that all technical men will be listed as such and they will be separate and distinct from the non-technical engi-neers. Thus, the next census will bring an enumeration of all technical engineers together as one unit under the main headings of civil, mech-anical, electrical and raining; architects also will be enumerated separately. This will enable the engineering profession, the Government or any other interested organization to know exactly how many technical men there are in the United States and in each state. The enumeration will also include non-technical engineers, except that there will be no such heading and in order to get the totals of non-technical men all of the various grades of this classification would have to be sorted out and added.

Jan 12, 1919

By G. C. Mudd, E. J. Myers

Within the last 15 years David Brown Gear Industries has manufactured approximately 200 large mill gears over 6m diam., 58 of them over 9 m and up to 12 m diam. The experience has not been without problems, due to a lack of clear understanding of the loads and stresses imposed on large gear wheels. American Gear Manufacturers Association (AGMA) practices suggest that a service factor be used for mill gears. But what is meant by "service factor"? The layman might be forgiven for believing that the term is synonymous with "safety factor," but this is certainly not true. The service factor is an aggregate of the following in some proportion: -An application factor, i.e., an allowance for the fact that systems do not run smoothly with uniform torque. -An ignorance factor covering the imperfections in the basic gear calculation. -Possibly a safety factor. In the following sections some of the ways in which the limits of applicability can be overstepped are discussed.

Jan 1, 1983

By J. HUNER

Twenty-four new fields were found in Louisiana during 1945. Of this number 15 were oil fields, eight were gas condensate, and one a dry gas field. None of these fields, with the exception of West Delhi, is as yet of any great consequence. The Weeks Island field in Iberia Parish may eventually develop into a considerable reserve.

Jan 1, 1946

By Gail Moulton

THE oilfields in Illinois are located principally along the LaSalle anticline in the southeastern part of the state. The oil produced comes most largely from beds of Pennsylvanian and Mississippian age, but there is an increasing important production from deeper horizons, as will be noted under new development. The oil is largely of paraffin base, and has an average specific gravity of about 35° Baume. The rank of Illinois as an oil producer has dropped from third since 1913, when its production was exceeded only by that of California and Oklahoma, to eighth in 1923. This has been the result of failure to find new pools of considerable size to offset the declining production of the old wells and of the greatly increased production of some of the other states. The noteworthy features of petroleum production in Illinois during 1924 are: the low rate of decline for the state as a whole; the smaller percentage of dry holes; and the larger average initial yield of the new wells.

Jan 3, 1925

By H. M. Howe

A Discussion of the paper of Professor Howe, presented at the London Meeting, July, 1906, and printed in Bi-Monthly Bulletin, No. 14, March, 1907, pp. 169 to 274. SECRETARY'S NOTE.-M. Beutter's introductory remarks, being simply a resume of Prof. Howe's paper, with a disclaimer of the intention to criticise it, have been omitted, and the remainder of this contribution has been somewhat condensed, without omitting any essential statements. M. BEUTTER, St. Etienne* (communication to the Secretary-+):-Professor Howe observes in paragraph 47 of his paper that the fluid-compression of steel. diminishes piping by forcing the liquid and viscous metal, while the pipe is forming, or after it has formed, into the space so produced, and proceeds to study the different systems of compression, alluding to the four principal ones: Whitworth, Illingworth, Williams, and Harmet. Having now for many years had in use the last-named process, that of M. Henri Harmet, I shall attempt to explain the difference between it and the three other processes named. The Harmet process does not diminish or close the pipe after it has formed, but prevents it from forming; and I may add that it is the only one of the four which produces this result. It is true that the Whitworth process diminishes the interior hollow by localizing it around the central axis of the ingot, which is afterwards removed by trepanning the hollow forgings for which this process has been, I believe, always exclusively used. The Illingworth and Williams processes, which, in my opinion, are applicable only to small ingots, of necessity allow the pipe to form, or (to use the expression of Professor Howe) they allow the surface of the lake of liquid steel to sink into the interior of the ingot, since they involve waiting a certain time before compression, so that (in the case of the Williams process) the ingot-mold can be opened without dan¬ger, or (in the case of the Illingworth process) so as to avoid the risk that the steel may enter the grooves produced by the removal of the distance-bars. During the time required for

Jul 1, 1907

By Gregory B. Baecher

Rock engineering involves uncertainties which are large and difficult to quantify. The traditional design approach to these uncertain- ties has been conservatism, and has been satisfactory to the extent that failure rates are reasonably small. Yet, a price is paid for conservatism, and that price is not always small. Today, reliability and risk analysis are finding use in rock engineering. The introduction of such methods, usually under the name 'probabilistic design,' is controverisal. However, if the jingoism of both sizes in this controversy is stripped away, it appears that new insights about uncertainty in rock engineering are emerging.

Jan 1, 1982

By Freeman Bishop

Copper production has been under Government scrutiny for many years because it's known as a concentrated industry which in turn creates what many economists label administrative prices. Neither of these conditions is illegitimate, per se, the Federal Trade Commission and the Justice Department have said time and again. But Justice spoke up once more. This time over a Puerto Rican copper development planned by American Metal Climax, Inc., and the Kennecott Copper Corp. Bureaucratic Dichotomy Creates Confusion and Conflict In the Copper Industry Ian MacGregor, chairman and chief executive officer of Amax, said Justice in a recent communique questioned the propriety of the proposal of a joint copper venture in Puerto Rico. At the same approximate time, Dr. Hendrik S. Houthakker, chairman of the President's Commission on Copper, was urging copper producers to expand production to help hold down prices by making more copper available to all consumers. This, Mr. MacGregor said, is creating confusion and conflict, since the Administration from one source is chastising the industry for doing what another branch requests.

Jan 1, 1970

By Henry G. Granger

DURING upwards of three thonsand miles of canoc-travel in South America, including several mishaps, the writer has unfortunately lost his book of notes taken during the year 1894 in Dutch Guyana, or Surinam. But a year spent in a foreign country, visiting its principal mining properties, is necessarily productive of indelible memories and impressions, and some of these may be of interest to the Institute. The Guyanas include British, or Demerara, Dutch, or Surinam, French, or Cayenne, and the Disputed Territory, or that portion of Brazil on the northeast coast of South America. After passing the picturesque mountainous coasts of Colombia and Venezuela, one reaches a low, flat mud-bank which extends far out into the sea, so that from the steamer, over a couple of leagues of turbid, shallow water, one call just see the dismal outline of the pestilential "bush" that fronts the Caribbean sea, clear around to the mouth of the Amazon. Here, iii the order mentioned above, are the Guyanas. So much has been said about this out-of-the-way section during the late excitement over the Venezuela boundary question, that the historical part of the subject may be advantageously condensed. Gold-mining in the Guyanas is altogether placer-mining, and is of the same general nature throughout; hence by describing the methods in use in Surinam and the results there achieved, ail idea will be given of the work throughout the field. The product of this section is about three to four millions of dollars annually, mostly from Demerara, not because of superior richness of its placers, but as a result of its very much larger population, which exceeds twice the aggregate census returns of both Surinam and Cayenne. Mining ill all this section is of comparatively recent date, and is indirectly due to the decline of the sugar-industry. After the introduction of beet-sugar scores

Jan 1, 1897

By William Allen

For the past six years gravity surveys have been used for underground prospecting in the copper mines at Bisbee, Ariz. The primary purpose of the surveys has been to reduce the diamond drilling and crosscutting necessary for exploration. Since many of the orebodies are small, and geologic control is not always apparent, any information that will direct the drilling and crosscutting is highly desirable. Because of extensive development and exploration work in the copper mines at Bisbee, it has been possible to cover more than 630,000 ft of crosscuts on 30 levels with the gravity surveys. In the process the gravity procedures have been refined to a high degree.

Mar 1, 1956

By Edwin B. Johnson

The success of self-fluxed sinter in enhancing the operation of the blast furnace during the past few years has reasonably led to the assumption that the use of self-fluxed pellets might result in even greater furnace efficiencies. A great share of development work in agglomeration has been directed towards techniques related to the production of self-fluxed pellets, but no appreciable tonnage of self-fluxed pellets had been produced on a commercial scale until this past year when The Cleveland-Cliffs Iron Co. produced 35,000 tons of such pellets by the grate kiln system at the Republic mine during the period May 21-June 5, 1962.

Jan 3, 1963

By E. Topuz, G. Faulkner, M. Karmis, C. Haycocks

The Appalachian coal region of Virginia, southern West Virginia and Kentucky and the extreme eastern portion of Tennessee constitutes a unique area of surface coal mining activities. The area contains a number of contiguously placed coal seams, up to a total of fourteen in some places, which vary in thickness from a few centimeters to 2,5 meters. Much of this coal is of high quality, some being the highest grade metallurgical coal found anywhere in the world. The region may be broadly characterized physiologically as a dissected plateau with a relief above the valley floors of up to 500 meters and a dendritic drainage pattern. Up to six seams may outcrop in the hillsides above drainage, many of which have been subjected to contour stripping operations. Prior to the passage of the surface mining reclamation act, little effort was made to reclaim stripped areas. The passage of the strip mining act, including the controversial requirement for returning the land to its approximate original contour, has forced intensive recla¬mation efforts from the mining industry. The wisdom of this original contour requirement has been the subject of considerable debate and litigation, mainly because of its cost, inconvenience, and value of the land after it has been reclaimed. Regardless of whether recla¬mation is carried out, under current practices slope failures do occur. This in effect circumvents the intent of the law and can expose large unvegetated spoil areas, and contribute to hillside erosion and stream silting. Such failures must be eliminated if further costly reclamation efforts are to be avoided.

Jan 1, 1983

By Edwin C. Eckel

The title of this study may fairly lead to misunderstanding unless its basal viewpoint is explained at the start. There is of course no chance of misunderstanding the term strategic minerals-for some years past it has been rather generally used to cover those mineral supplies, important for war use, which do not occur in adequate amount on the territory of the Power under consideration. Even here, however, I might add a note of warning. It is commonly understood that the list of strategic minerals will vary, according to what country we are considering; but it is rarely understood, even in Staff studies, that it varies equally according to the particular adversary we happen to be considering. In the present study I have stated the definition in the broadest possible terms, and have at this stage purposely avoided limiting it to any one country or war situation, with the express purpose of being free to bring out certain implications which are commonly, if not always, overlooked. The more important opportunity for misunderstanding is, of course, that my views on the phenomena war and peace do not coincide with those currently fashionable, particularly in advanced intellectual circles. For we must face the fact that for a decade past the natural reaction from war conditions has shattered the public mentality so completely that our public discussions of such questions have very little relation to fact; they are excursions into ideal rather than Realpolitik. And as such they serve merely to prevent public discussion or accept-

Jan 1, 1932

By Leonard Logan

Production control in the petroleum industry may be discussed under three general heads: engineering, legal, and economic. Though the problems that fall under the respective heads of engineering, law, and economics are separate, they are dependent and interrelated. The present study will deal with the economic phases of production control and only incidentally with the legal phases as they affect the economics of the problem. No one of these forms of control is more important than the others. The engineers have performed their service well, and although there are many problems of engineering control yet to be solved, they are not pressing. Legal control is a problem for the legislatures and the courts to solve. The petroleum industry is such a comparatively young industry and the legal problems are of such recent origin that the courts have not yet been called on to settle all the issues and the legislatures still have before them bills concerned with the regulation of the industry. Economic control of production in the petroleum industry is a highly desirable goal but it has not yet been completely achieved. Since the first commercial well was drilled in 1859, there have been recurring periods of overproduction. (Over- production will be used here to describe a condition wherein so much crude oil is available that a satisfactory and reasonable price is not received for the product.) The production of oil in 1859 approximated only 2000 barrels. In the following year production jumped to 500,000 barrels, thus bringing into

Jan 1, 1932

By Rudolph Emmel

THE mines operated by the South American Development Co. are located in the Zaruma mining district of southwestern Ecuador. They are near the old mining town of Zaruma, which is the only important city in the canton of the same name. The district is situated in the upper end of a valley lying between two spurs of the Cordillera, one of which may be considered the Coast Range and the other an intermediate range. The mining camp proper, known as Portovelo, and the plant are 2.4 km. south of Zaruma, on the north bank of the Amarillo River, a tributary of the Tumbes River, which flows southwestward through Peru to the Pacific. Portovelo is difficult of access; it is reached from Guayaquil by means of river steamers and muleback. Embarking at Guayaquil, the route is down the Guayas River, across the Jambeli Canal, and up the Santa Rosa River to Santa Rosa, a distance of 177 km. From Santa Rosa, the road or trail follows the Santa Rosa River, then across the summit of the Coast Range into Portovelo, a distance of 74 km.-a two-day trip on muleback. The mining property of the South American Development Co. comprises 297 lode claims and 142 placer claims. The combined lode claims cover an area, roughly rectangular in shape, 9000 m. long from north to south by 4000 m. wide; the northern edge of the rectangle is about 3000 m. north of the central plaza of Zaruma. Mineral lands in Ecuador are held by virtue of an annual tax per claim paid to the central government, no surface rights being included.

Jan 1, 1925

By C. D. Demond

IN reverberatory smelting, fuel is the chief item of expense, as it commonly is in processes using large percentages of it. Hence the most suitable supply is eagerly sought; that is, the supply which, in the end, yields the greatest net profit. The better grades are not infrequently bought, even at an advanced price, because they are apt to be decidedly more economical. High price, of itself, however, is no merit, for freight is generally the largest part of the cost of fuel, and the nearby supply may yield as high efficiency as that from a greater distance. If a poorer grade is reasonably good, and if its cost is low enough to more than offset the decreased technical efficiency, it is of course the more suitable. Any smelting, operation depends for both efficiency and economy on raising the furnace atmosphere considerably above the "critical" temperature; that is, above the temperature at which smelting is completed. If this temperature is not exceeded, smelting stops, no matter how much coal is burned; and the real value of a fuel depends on the number of degrees that the temperature is continuously kept above this point. For example, if one fuel maintains 2,500° F. and another only 2,100° F., while the "critical" temperature is 2,000° F., the first is worth at least five times as much as the second, although the increase above atmospheric temperature is only one-fifth more in one case than in the other. This "margin of temperature" above the smelting point is much more significant than the total number of heat units developed from the fuel. The case is parallel to that of water flowing from a pipe. The reservoir may contain a billion gallons of water; but, even though the fluid has come to the nozzle, not a drop will run out, where it can be of practical use, unless the level in the reservoir is higher than the nozzle; and the speed and volume of flow depend on how much higher the level is in the reservoir than at this point. If the temperature inn a furnace is not above the critical level there will be no slag to flow over the skimming plate, even though there are enough heat units to bring an unlimited quantity of charge up to the point of slag formation; and just as the value of a water supply for the purpose of putting out a fire depends largely on the effective head, so the difficulties of furnace management

Jan 8, 1914

By L. A. Rose

AMONG the half-dozen major research search projects now being conducted at the Michigan College of Minim, and Technology under the terms of an FERA grant, an important one relates to the use of suspensions in ore dressing. The study has resulted from the constantly widening industrial use of metals and minerals. The modest demands of a few decades ago for these minerals could be easily met from richer deposits. Now, at least in some localities, the richer deposits are nearing exhaustion. Furthermore, advances in the industrial arts and the competition of other minerals and metals have changed the specifications of materials needed by the manufacturers. Premiums and penalties enter into the sale value. Hence, to meet the requirements for amount and quality, washing and other ore-dress-

Jan 1, 1935

By J. Elmer Thomas

If 1929 witnessed a growing realization on the part of the oil industry that supply must be balanced against demand, 1930 proved conclusively that excessive inventories constitute a price depressant even with balanced conditions. Increased attention was certainly paid to economic considerations last year, and the achievement of holding daily crude production, with a constantly mounting potential, to levels 500,000 bbl. below the output of the summer before, deserves special mention. The ill-advised accumulation, however, of gasoline stocks, at least 10,000,000 bbl. larger than necessary, nullified the restraint exercised by the producers and finally necessitated drastic downward price revisions. An event of special significance was the appointment by the Federal Oil Conservation Board, last March, of a temporary Committee on Petroleum Economics that attempted a forecast of demand, an estimate of supply, and an allocation of the latter between the principal producing states. Thus for the first time was an economic program for an entire basic industry drafted by an independent body under the auspices of the Federal Government. The report was widely discussed and generally approved, but its schedules were not adopted by the refining division nor by oil producers in the State of Texas until too late to contribute to the industry's prosperity during 1930. If the restraint of November had been exercised in May a profitable year might have been the result: The gasoline price war in California during June, however, illustrated the point that even with a fairly sound statistical position insistent pressure to expand normal marketing outlets must result in losses to all concerned. The balanced program so painfully attained by producers must be maintained by refiners and distributors to be completely effective. Again in November the Federal Oil Conservation Board, acting on the request of the directors of the American Petroleum Institute, called its Committee on Petroleum Economics back into existence to prepare a new estimate for the next six months. An economic program adopted in advance of the winter period of accumulating inventories may aid this large and essential industry toward the profits to which it is entitled

Jan 1, 1931

By W. H. Adams

I DOUBT if many of our engineers know of the existence of coal-fields extending over hundreds of miles of territory bordering on and lying contiguous to the Rio Grande River in Mexico. Essential as these facts are to those contemplating the starting of industrial works along our frontier, I have not been able to learn that any surveys or examinations have been made of these deposits, and I trust the preliminary and unofficial investigations lately made by myself may be found of interest, especially to those of our members whose experience has been with poor fuel, or in districts remote from railway facilities. While it is true that Northern Mexico is generally bare of charcoal-making timber, yet no greater mistake can be made than to condemn the light, quick-growing woods found in profusion, and which cannot be excelled in flame or heat-producing qualities for boilers, reverberatory furnaces, or hearths. No country could be surer of a full supply of wood if wise legislation in regard to irrigation and preservation of young timber were adopted and enforced, but the beneficiation of the low-grade ores of Mexico demands a more dense fuel for furnace work, and, fortunately for metallurgists, who will hereafter make this frontier a base of operations, there have been disclosed, near the surface, seemingly inexhaustible beds of semi-anthracite and bituminous coals. No extensive openings have as yet been made, and my own workings at the Cedral mines are all that can yet be said to prove the quantity and quality of the coal, other openings furnishing only corroborative evidence. Our location (one hundred and ten miles west of the Rio Grande River) is on the western line of the depository basin, as it has existed since the period of activity along the volcanic line. The region farther inland I have not examined, but the elevations, as a rule, are much greater, though from the nature of the formation, they are not necessarily barren-ground. Beginning at the base of the Santa Rosa Mountains (location of the Cedral mines), we find very interesting breaks in the foot-hills, disclosing the stratified rocks from the volcanic centres to the valleys.

Jan 1, 1882