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By G. G. Oberfell

THOUGH the largest volume use of natural gas has been, is. and in all probability will continue to be as a fuel for domestic and industrial heating, it has various market outlets, both as a fuel and as a raw material for the chemical industry. Natural gas is a preferred type of fuel where ease of control, fuel uniformity, and freedom from ash are of primary importance. Other industrially important uses are as a source of carbon black and as a fuel in various low-cost heating operations. Many other uses are of varying importance and new potential uses are continually being uncovered, some being of economic importance to the gas indus¬try as a whole, but most of them involve such small volumes of gas that they are only of passing interest. Since various products extracted from natural gas and recovered as by-products from petroleum refining, such as liquefied petroleum gas and fuel oil, are being utilized in many industrial and domestic heating applications, some consideration will have to be given such materials in order to present a reasonably complete story of the importance of natural gas. Some of these materials may prove to be transient competitors and will not be available when more profitable uses are found for them. Meanwhile, however, the potential volumes of such materials available, the current volumes being marketed, and the nature of the utilization are considered as constituting an essential part of the over-all fuel picture.

Jan 1, 1946

Jan 1, 1966

By F. Weinberg, L. MacAulay

DAVIS,' in an investigation of solute redistribution along molten rods of dilute silver in tin, concluded that at horizontal temperature gradients below approximately 5°C per cm very little convective mixing takes place. Cole and winegard2 observed temperature oscillations in horizontal melts of tin, with temperature gradients of several deg per cm. They associated the temperature oscillations with the presence of convective flow in the melt. At temperature gradients less than 1°C per cm they did not detect convective flow. In the present work, direct measurements of con-vective flow in liquid tin have been made using a radioactive tracer technique. The results indicate that extensive convective flow occurs at temperature gradients below those previously reported. The apparatus used to determine the extent of con-vective flow is shown in Fig. 1. The graphite boat Fig. l(a), has two rectangular channels both of which contain molten tin. Radioactive Ag110 in the form of Sn-0.2 pct Ag alloy was introduced at the end of one channel, by rotating the cylinder shown. A series of fixed thermocouples were positioned along the center of the second channel to determine the temperature gradient. It was assumed that the two channels had identical temperature distributions. The graphite boat was inserted into a vycor tube which was surrounded by a multiple winding tube furnace as shown in Fig. l(b). The tin was melted in an argon atmosphere. The distribution of Ag110, as a function of position along the boat at a given time after introduction of the ~g"', was determined with the

Jan 1, 1970

Jan 1, 1971

Jan 1, 1970

By AIME AIME

THE growth of the spirit of progress and mutual aid which motivated the founders of the Institute sixty years ago in Wilkes-Barre was vigorously demonstrated at the sixtieth anniversary meeting held there on May 22. Committees headed by Cadwallader Evans, "resident director" of the Institute, and Paul Sterling, chairman of the local section, had arranged for a full-day tour of the northern anthracite field, so that the hundred and fifty members and guests who had come for the celebration of the anniversary might see the changes and progress made in that field in recent years. More than forty automobiles were in line in the cavalcade which left the Westmoreland Club at nine- thirty. Operations visited were fully described in the May issue of MINING AND METALLURGY, so it is enough to say that after a seventy-five mile drive through the beautiful Susquehanna Valley and over the rolling green hills of northern Pennsylvania a stop was made for lunch at Forest City. Carey, Baxter and Kennedy, contractors at the stripping operations there, had provided, in the shelter of tents, a well-prepared luncheon and other refreshments. The return trip was made by way of Scranton, arriving at Wilkes-Barre at five- thirty.

Jan 1, 1931

Jan 1, 1967

By AIME AIME

The XCVIIth meeting of the Institute for the reading and discussion of papers will be held at Spokane, Wash., beginning Monday, Sept. 27, 1909, as already announced in Special Circulars of May 8 and Aug. 14, 1909, and in the Bulletins for June, July, and August. The meeting will be preceded by a tour through Yellow stone Park and visits to Butte and Anaconda, and will be followed by visits to the Coeur d'Alene district, to the Alaska-Yukon-Pacific Exposition at Seattle, to the mining- and smelting-plants near Salt Lake, and to the iron- and lead- and zinc-plants at Pueblo. The special train for the party' will leave Chicago, September 16, and return about October 12. Details of the itinerary are given later in this announcement. The Secretary of the Spokane Local Committee is Lyndon K. Armstrong, 615 Hyde Block, Spokane, Wash., to whom should be addressed all inquiries concerning local matters. The control of the papers and proceedings will remain in charge of the Institute office, as usual. It is greatly to be desired, both in behalf of the Institute and in recognition of the many courtesies to be extended on the trip, that the excursion party be made larger. Exceptional facilities to visit the many mines and smelters have been freely provided; and members are requested to make all reasonable effort to attend the meeting at Spokane and participate in the excursions. For those who cannot join in the entire trip, it may be possible to provide special Pullman accommodations after leaving Yellowstone Park. In order to make the necessary arrangement, however, the names of members and guests contemplating this partial trip should be sent at once to Theodore Dwight, 29 West 39th Street, New York City. The general cost of the trip per member will be $300, which includes transportation, berth, and meals for the entire trip from

Sep 1, 1909

Jan 1, 1968

Jan 1, 1968

By C. D. Thurmond

Jan 1, 1968

Jan 1, 1967

Jan 1, 1969

Jan 1, 1966

By Carl Henrich

Jan 1, 1893

By N. S. Wagner, R. S. Mason

The production of lightweight aggregates in Oregon is a new industry, and, like all new enterprises, it is suffering from growing pains characterized by numerous, small operations some of which flourish for a short time and then cease altogether. Norinally all industrial mineral products are produced in a highly competitive atmosphere. At the present time this condition does not exist to a very marked degree in the state because as yet producers have not saturated the constantly expanding market. This paper has been prepared with the intention of outlining very briefly the current status of the various products now heing used as lightweight aggregates in Oregon. The present piche will surely change, perhaps quite radically within even a short space of time. Lightweight Aggregates Used in the Northwest PUMICE Interest in Oregon pumice is not new. Deposits are abundant. Successful development, however, dates only from 1946. During 1948 a total of nine operations was engaged in full or part-time production of aggregate. The postwar building boom and increased public consciousness regarding the value of insulation are the immediate reasons behind the current development. Just how firmly this production of pumice aggregate may be established is something which cannot be foretold at the present time. Much will depend upon how successfully the pumice aggregate construction already installed stands the test of time. Some fine pumice aggregate products have been made and it seems probable that because of its unique properties a certain demand for pumice aggregate will continue in the future. Fire-proof, rodent-proof, decay-resistant properties supplement the lightness in weight and insulation properties of pumice aggregate products in rendering them particularly ideal for many types of construction. In addition there has been fabrication in the form of reinforced fence posts, street markers, and similar products of a specialized-product nature and these are not to be overlooked in terms of future production. Also pertinent to how soundlj pumice aggregate production is established will be possible future competition with other lightweight aggregates. However, this situation will be governed largely by competitive costs of production and marketing. For its present use, which is almost exclusively limited to the manufacturing of building blocks, the market for Oregon pumice aggregate has been extended from the mining area around Rend and Chemult to points as far distant as San Francisco and Seattle. Naturally enough the bulk of the production goes to the Portland and eastern Oregon consumers. Shipments are made by both rail and truck. Early in 1947 the State Department of Geology and Mineral Industries made a canvass of all pumice producers in the state. The production for 1956 amounted to 26,614 cu yd and was valued at $13,649 at the plants. The United States Bureau of Mines estimates the production for 1947 as 33,240 short tons valued at $111,380. This is roughly 65,000 cu yd. No data are available for the 1948 production but it is understood to exceed that for 1947. The Oregon pumice occurrences originated largely from the eruption of Mount Mazama, the name of the formerly active volcano and the location of Crater Lake. Other lesser volcanoes throughout the area contributed to the present occurrences, however, and it has been estimated by Moore' that the pumice deposits cover an area of some 3500 square miles. This area lies east of Crater Lake between Bend and Klamath Falls and embraces the southern portion of Deschutes County, the northern part of Klamath County, and the northwest corner of Lake County. Thickness of the pumice ranges from thin skims to local thicknesses of as much as 30 to 40 ft. Fragment size also varies greatly. Any attempt to describe the situation by giving screen analyses would be confusing because of the wide variations to be found in all area of this size. The picture can best be summed up by stating that places showing great variations in fragment size can be found if a search for extremes is made. For mining purposes in connection with aggregate production, it call be stated that miles and miles of pumice exist in which the fragrnent sizes range from an inch or so downward. The usual color of the pumice is a light gray to off-white. A typical pumice analysis shows a silica content of about 69 pct, alumina 15 pct, and sodium oxide about 5 pct. Potash, lime, and water are the next three most abundant constituents, running just a little over 2 pct each. Iron oxides are fairly constant at 2.75 pct. Titanium, manganese, magnesium, and phosphorus occur in amounts of less than 1 pct. All of the foregoing substances are combined as a glass exhibiting cellular structure. The weight of crushed but otherwise pit-run (undried) pumice runs around 1100 Ib per cu yd according to figures furnished by various producers. The minimum and maximum weights per cubic yard reported are 1050 and 1400 lb, respectively. The 1400 lb per cu yd pumice contrasts with the pumice from most of the other

Jan 1, 1950

Texture Transition in Ordered CuAu, by E. A. Starke, Jr., J. C. Ogle, and C. J. Sparks, Jr., Trans. TMS-AIME, 1969, vol. 245, pp. 169-70. pole figures should have had two parts not one. On the Estimation of Oxygen Absorption by Continuous Molten Metal Streams, by J. Szekely, Trans. TMS-AIME, 1969, vol. 245, pp. 341-44.

Jan 1, 1970

By M. W. BERNEWITZ

DURING my recent extended visit to Australia and New Zealand, these notes on oil and gas prospecting in that part of the world were compiled from recent reports-press and government, from conversation with one of the financial leaders in the search for oil, and from personal observation of operations of the principal importers, blenders, and distributors of oil products; also from the astonishing testimony given by them to the Petrol Commission. Australia and New Zealand have practically no petroleum production beyond a few thousand gallons a year from wells in the latter Dominion. Everything is imported, Table 1. showing the quantities for 1929-30 in Australia and for 1930 in New Zealand,

Jan 1, 1934

By David W. Brunton

I. INTRODUCTION. THE list of our past-Presidents comprises the names of runny who, in their official addresses, have sketched the current progress of the arts and professions with which they were familiar. Such addresses are, in my judgment., highly useful, setting forth the results of our own work as a. society, and recalling to our minds the particular lines in which discussion would prove most fruitful. . Following this course with some hesitation, I venture to offer an outline of the recent improvements and the present situation in minim and metallurgy in the Western United States. The wonderful advances in mechanics, chemistry, and electricity have all combined to aid these arts to such an extent that. progress during the last decade has undeniably been more rapid than ever before in the history of the profession.. In all mining countries improved transportation-facilities, in many instances called into existence by the traffic created by the mines themselves, have done much- to enlarge the. field of operations by the reduction of freight-, operating- and living-expenses, thereby bringing lower-grade properties into the producing class. Under normal' conditions, as the age of a district in¬creases, all these differentt factors should combine to off-set. the augmented costs attendant on deep mining, and greatly tend to prolong the profitable life of the mines. The more recent and important improvements in our Western mining-practice which have contributed most toward the advancement of the art may be briefly summarized as follows; but, before beginning this portion of ray address, I wish to thank most heartily the many engineering friends who have so

Sep 1, 1909