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By Albert Sauveur

SOME writers believe that when austenite transforms completely into pearlite on slow cooling through the thermal critical range, such transformation does not imply the formation of any of the so-called transition constituents: martensite, troostite and sorbite. Might it not be claimed with as much justification that when water freezes it does so suddenly, solid ice being obtained without passing through the intermediate stages of ice and water? Obviously, regardless of the speed of solidification, this would be erroneous. Before reaching the completed solid condition, this must of necessity pass through an unbroken series of stages when the system consists of mixtures of water and of ice, the former decreasing and the latter increasing in amount. Are not these "transition" stages in the freezing of water similar to the transition stages occurring in the transformation of austenite into pearlite? To clarify, let us consider in Fig. 1 the mechanism of the transformation of eutectoid steel from its austenitic to its pearlitic condition as it cools slowly through its thermal critical range. It is generally admitted that this transformation is the result of two distinct phenomena: (1) the allotropic change of gamma iron into alpha iron and (2) the crystallizing out of solution of the carbide Fe3C. Whether this crystallizing of Fe3C implies also its formation is immaterial for our purpose. In other words, whether it is the carbon in atomic dispersion which is present in gamma iron or molecules of Fe3C has no bearing upon the matter to be discussed. The transformation of gamma iron into alpha iron cannot take place suddenly. It must of necessity be progressive, regardless of the speed with which it may take place. At A, for instance, there would be present AB gamma iron and BC alpha iron. The distance MN does not refer to falling temperature, but to the passage of time. It may be assumed that the transformation takes place at a constant temperature (the Ar321 point). In a similar way, the crystallization of Fe3C out of the austenite solid solution must be progressive as depicted between M and N. At A there would be present AB gamma iron, BC alpha iron, CD carbon dissolved in gamma and in alpha iron and DE Fe3C. This condition may be described according to individual preference as martensite or troostite. To sum up, can the metal pass from condition

Jan 1, 1931

Jan 1, 1949

By C. W. Reith

The development of production in West Texas during the year 1933 was largely confined to the expansion of proven areas, especially Ward County, Iatan and North Winkler. Wildcat activity was at a comparatively low ebb and resulted only in discoveries of probable minor importance in Ector County. The interest shown in deep wildcatting to test beds of pre-Permian age was a new development, which should soon throw light on the possibilities of deeper production from the present producing fields. The important pre-Permian tests of the year were: 1. Stanolind Oil and Gas Co., Todd No. 1, a unitized test, in north central Crockett County on a probable continuation of the Big Lake trend. The well encountered several showings of oil and penetrated an Ordovician section very similar to the productive zones at Big Lake, but was abandoned when sulfur water was encountered at 8041 feet. 2. Gulf Production Co., McElroy No. 103, in the McElroy Field, Upton County. The well was drilling at 8553 ft. at the close of the year in beds of probable pre-Permian age. The test is an important one because it should prove or disprove deep production in the Church-Fields-McElroy pools and also throw geologic light on the deep possibilities of other fields in the western part of the Permian Basin. 3. Humble Oil and Refining Co., White and Baker No. 1, in Pecos County, about 11 miles west of the Yates field. The well is on a nonproductive Permian high and should indicate the deep possibilities of the Yates field. At the end of the year, drilling had progressed to 7200 ft., where beds of pre-Permian age are believed to have been penetrated. The major fields in West Texas, in which present-day proration had its inception, were produced under increased restrictions. A date of importance in the proration history of the area was $ept. 8, 1933, when the Railroad Commission issued an order placing all producing wells under proration. The severe reductions in total outlet made during 1933 were well compensated for by a more than threefold increase in the price of crude oil. Acid treatment was one of the general engineering developments of interest. The work had not progressed sufficie~ltly at the close of 1933

Jan 1, 1934

Jan 1, 1884

Jan 1, 1908

Jan 1, 1964

Jan 1, 1910

By G. C. Gester

Oil has been produced in Persia and India for many years, but it was not until 1932 that Arabia entered the arena as a potential oil-producing area. In 1930 the Standard Oil Co. of California acquired a concession covering the rights of exploration and exploitation for oil in the Bahrein Islands and in June, 1932, the first commercial production was discovered by the bringing in of a well known as Jebel Dukhan No. 1 on the Island of Bahrein. Since then the Standard Oil Co. of California through its wholly owned subsidiary, The Bahrein Petroleum Co. Ltd., has been carrying on a systematic survey and development program of its concession in the Bahrein Islands. This group of islands, of which Bahrein is the largest, is in the southwestern portion of the Persian Gulf, approximately 25 miles from the mainland of Arabia. Although geographically a part of Arabia, the islands are not a part of the Kingdom of Saudi Arabia. Their government is essentially independent but certain special rights have been granted to Great Britain through a series of treaties. The Island of Bahrein is 32 miles long by 9 1/2 miles wide and covers an area of 215 square miles. Approximately three-fourths of the island is occupied by a relatively low, broad, elliptically shaped dissected hill, the central part of which is slightly depressed with inward-facing cliffs but culminating in the Jebel Dukhan (Hill of Smoke), which rises to an elevation of 443 ft. above sea level. The topography of the island is a good index of its geologic structure. Structurally the island is an elongated dome or quaquaversal fold composed of rocks of Eocene age. The major axis of the fold strikes N.5W. All of the topographic high portion of the island is a part of the structural uplift. The crest of the fold is broad and flat with the dips increasing on the flanks. How far tilted strata may continue beyond the line where the Eocene beds are covered by recent sands and detrital material is not known. Superimposed on the general structure are a few small irregularities in the form of minor folding and faulting. There is, however, no evidence of any major faults. The largest of the irregularities lies to the south of Jebel Dukhan and has the appearance of a sink

Jan 1, 1934

By D. H. Wertz, R. R. Furlong

Dry room equipment at Donora Zinc Works is of the design which prevailed at the time the plant was built in 1915. It consists of 11 adjoining rooms, each being 99 ft long, 11 ft wide, and 7 ft high and having a capacity for 1040 retorts. Heat is supplied by steam coils beneath the slatted wood floor and by warm air ducts at the ceiling. Drying practice is about the same as that generally followed in the industry except that, under normal zinc furnace operations, the maximum drying time is 45 days. During certain seasons of the year the drying process was seriously affected by varying weather conditions which frequently resulted in a scrap loss of 5 to 7 pct. Because of these unfavorable conditions, which caused uneven drying and strains in the retorts, increased retort failures in the zinc furnaces were recorded. Regulation of temperature and humidity under all conditions appeared to be the logical solution of this problem. Controlled drying had been developed for a number of ceramic products and investigation of several such drying processes in this area revealed favorable results. Along with control of drying conditions and the attendant decrease in scrap losses, plant operators also reported a material reduction in drying time. Another factor affecting the decision to proceed with this development was the drastic change in market conditions for retort clay. Curtailment of shipments from the chief source of supply made it necessary to proceed with blending of other available clays, but quality of these clays was questionable for adequate retort life in the 24 hr furnace cycle. Rapid furnace testing of new mixtures was desirable but impossible with the prolonged drying schedule. Therefore development of a controlled drying process for zinc re- torts offered the solution to the problem of rapid testing of retort mixtures. Description of Process and Equipment The freshly extruded retort is cylindrical in shape, 58 in. long, 9 in. id and has 1 1/8 in. side walls. One end is closed and approximately 2 in. thick. The moisture content of this "green" retort is about 17 pct which means a necessary removal of 30 lb of water per retort. Retorts are set on the slatted floor of the dry room with the closed end down. The controlled drying process depends upon the circulation of a large volume of conditioned air at low velocity. To provide for uniform distribu-

Jan 1, 1950

Jan 1, 1934

By E. J. Duggan

It is a coincidence that the two plants in this country for treating copper ores by ammonia leaching came into existence at almost the same time, that of the Kennecott Copper Corporation at Kennecott, Alaska, in March, 1916, and that of the Calumet & Hecla Mining Co. in July of the same year. The success of both from their very beginning attests the merits of the process under widely different sets of conditions. As would be expected, in the time they have been operating these two pioneers in this field have greatly perfected their methods and improved their technic. The early difficulties inevitably encountered in undertakings of this nature have been largely surmounted and the process may now be considered to be well seasoned and matured. There have been no other commercial plants built in this country and but one elsewhere, the Bwana M'Kubwa in Northern Rhodesia, for the reason that this method of treatment may be employed on comparatively few ores. However, it has certain advantages, some of which are inherent to sand leaching processes generally and some to ammonia leaching in particular. Among these may be enumerated: (1) the avoidance of fine grinding; (2) the small amount of water required; (4) a high-grade product; (5) little likelihood of deleterious gangue constituents and fouling of solutions. It is true that great progress has been made in recent years in the flotation of the ores that come within the province of ammonia leaching. Nevertheless ammonia leaching has its possibilities and these may be overlooked in the present tendency toward the use of flotation for all ores. Probably the chief requisite to its further extension to suitable ores will be a cheap source of steam. Ammonia, the only reagent required, is unlimited in supply, readily transported and the price that is likely to obtain in the future should not make its cost at all onerous. Choice of Method for Kennecott Ores The Kennecott ores are typical limestone replacement deposits. The milling ores have a copper content of approximately 8 per cent in a limestone dolomite gangue. About half the copper occurs as sulfide, mostly chalcocite with some covellite, and the remainder in the form of the two carbonates, malachite and azurite. A comparatively coarse grind followed

Jan 1, 1934

By W. H. Eardley

It is increasingly evident that the excellence of blast-furnace operation to a great extent depends upon the preparation of the products fed into the furnace. The preparation of these products is carried on largely in the roasting and sintering departments. Prior to the building of flotation plants in Utah and other western states for the treatment of lead-zinc ores, the gravity concentrates received at the Midvale smelter amounted to about 4000 tons per month, containing 24 per cent. lead and 10 or 11 per cent. zinc. This product was about 20 mesh—that is, 45 per cent. of it would be plus 20 mesh and the balance minus 20 mesh. About 1000 tons of pyrite per month, containing 5 per cent. lead and 10 per cent. zinc, was also received. These products were sent to the multiple-hearth roasters for calcining, after which they were sent to the Dwight-Lloyd machines for sintering with other ores. The sintering charge passed over the machines but once. The first flotation products received consisted of a wet, sticky, muddy mass, containing a large amount of moisture, up to 19 or 20 per cent., and it was almost impossible to feed them with any degree of regularity, if at all, through our standard feeders; but the amount of flotation product received during the first year or so was relatively small and it virtually lost its identity by being mixed with a large amount of jig and table concentrates. As the quantity of flotation products increased, more efficient filtering was accomplished and the moisture greatly reduced. Flotation Products Received At the present time the Midvale plant receives about 4300 tons per month of flotation product running 60 per cent, lead and 4.5 per cent. zinc, 85 per cent. of which is minus 200 mesh and contains about 8 per cent, moisture; and 4000 tons per month of pyrite of similar fineness, running about 2 per cent. lead and 3.5 per cent. zinc, containing about 10 per cent, moisture. The lower moisture greatly reduces the difficulties of handling, making it possible to run a 100 per cent. flotation feed on a multiple-hearth furnace without serious mechanical troubles. The calcine, however, would contain nodules and balls of unroast,ed concentrates, sulfur elimination

Jan 1, 1928

F. E. BACHMAN, Port Henry, N. Y. (written discussion*).-Experi-ments with titaniferous ores found in Essex County, New York, made by the MacIntyre Iron Co. in 1914, showed' that titaniferous concentrates are reduced in the furnace with no greater, and probably with less, expenditure of heat, and consequently of fuel, than non-titaniferous mag-netites; and as a greater proportion of their oxygen is removed by carbon monoxide than is the case with non-titaniferous magnetites, a lower fuel consumption for the reduction of iron may be expected. After the furnace was blown out at the end of the experiment, the formation in the hearth was found to be abnormal. The brickwork was replaced, entirely around the furnace, by a layer which at -the tuyere circle was made up of cinder, fine carbon, and coke; the coke, however, gradually disappeared toward the bottom, being replaced by cinder and graphite. The usual salamander of graphite and iron was missing. The material left in the hearth seemed to be cinder that had not drained from the last cast; its composition, though, would indicate that it was in the furnace previous to the taking off of the titaniferous ore. At first, this material was thought to be blast-furnace cinder mixed with less iron and graphite than is normal; but an examination showed it to be made up of cinder with small masses of iron and graphite. There were also patches of a steel-gray material having a metallic luster; a microscope showed these patches to be made up of black metallic crystals interlacing white crystals.

Jan 11, 1919

By W. H. Eardley

IT IS increasingly evident that the excellence of blast-furnace operation to a great extent depends upon the preparation of the products fed into the furnace. The preparation of these products is carried on largely in the roasting and sintering departments. Prior to the building of flotation plants in Utah and other western states for the treatment of lead-zinc ores, the gravity concentrates received at the Midvale smelter amounted to about 4000 tons per month, containing 24 per cent. lead and 10 or 11 per cent. zinc. This product was about 20 mesh-that is, 45 per cent. of it would be plus 20 mesh and the balance minus 20 mesh. About 1000 tons of pyrite per month, containing 5 per cent. lead and 10 per cent. zinc, was also received. These products were sent to the multiple-hearth roasters for calcining, after which they were sent to the Dwight-Lloyd machines for sintering with other ores. The sintering charge passed over the machines but once. The first flotation products received consisted of a wet, sticky, muddy mass, containing a large amount of moisture, up to 19 or 20 per cent., and it was almost impossible to feed .them with any degree of regularity, if at all, through our standard feeders; but the amount of flotation product received during the first year or so was relatively small and it virtually lost its identity by being mixed with a large amount of jig and table concentrates. As the quantity of flotation products increased, more efficient filtering was accomplished and the moisture greatly reduced. FLOTATION PRODUCTS RECEIVED At the present time the Midvale plant receives about 4300 tons per month of flotation product running 60 per cent. lead and 4.5 per cent. zinc, 85 per cent. of which is minus 200 mesh and contains about 8 per cent. moisture; and 4000 tons per month of pyrite of similar fineness, running about 2 per cent. lead and 3.5 per cent. zinc, containing about 10 per cent. moisture. The lower moisture greatly reduces the difficulties of handling, making it possible to run a 100 per cent. flotation feed on a multiple-hearth furnace without serious mechanical troubles. The calcine, however, would contain-nodules and balls of unroasted concentrates, sulfur elimination

Jan 1, 1928

Jan 1, 1883

By Valentin R. Garfais

The world's petroleum production in 1928 is estimated at 1,322,896,-000 bbl., an increase of about 62,000,000 bbl. over 1927, as compared with an increase of over 133,000,000 bbl. in the previous year. The daily average was close to 3,600,000 bbl., of which the fields on the American continent produced about 84 per cent. The most important development during the year has been the partial success of the attempts to temporarily control production without appealing to legislation and, as a consequence, the increasing realization that, in order to reach a permanent cure for this situation, some form of legislation is necessary to' make possible the conservation of the oil supply and the stabilization of the industry. The importance of such a control over American production is not merely local but worldwide, as the American oil supply is now and for years to come will be the controlling factor of the industry. United States.—Production in the United States, which in 1927 increased about 15 per cent. over the previous year, remained practically stationary in 1928, the total being estimated at 902,000,000 bbl., or 68.2 per cent. of the world's output. This uniformity in production during the last two years was due primarily to the curtailment of output from wells already drilled, it being estimated that the available or shut-in production at the end of the year was close to 500,000 bbl. per day, or equivalent to the combined production of Venezuela and Russia, the countries ranking second and third. Venezuela.—With a production estimated at 106,000,000 bbl., Venezuela has trebled its output in the last three years. The increase in 1928 was 43,000,000 which placed this country as second in rank, a position which it should easily maintain for years to come. The output could have been considerably larger had not the oversupply in the United States made it advisable for Venezuelan operators to enter into tentative conservation agreements. Russia.—In Russia, production has doubled in the last five years, and reached a new peak in 1928 with an output estimated at 87,800,000 bbl., or an increase of 10,000,000 bbl. over the previous year. Difficul-

Jan 1, 1929

By James Kemp

IN THE Alumni catalogue of Amherst College and with the Class of 1848 is recorded the name of Louis Palemon Ledoux, who on graduating studied for the ministry at the Union Theological Seminary in New York and was ordained by the Presbyterian church. Louis Palemon Ledoux entered college from Louisiana and, as his name implies, was of French ancestry. His departure from the traditions of his forebears in register-ing in a Protestant college and later becoming a Presby-terian minister brought about some alienation from his family which, however, softened with the passage of years and disappeared between later generations. In time the Rev. Louis P. Ledoux was married to Kate C. Reid of New York City and was stationed for a year at Newport, Ky., where on Nov. 2, 1852, his oldest son Albert Reid Ledoux was born. The next year, the family moved to Monroe, Mich., where for two years the young clergyman was pastor of the Presbyterian church. A call to Richmond, Va., then led them to live from 1855-1858 in the, Virginia capital, but the father became afflicted with what was then regarded as a mysterious ailment, malaria, and to escape it migrated in 1858, when the young boy Albert was a little over five years old, to Cornwall-on-Hudson, and became pastor of the Presbyterian church in the lower village near the river. In 1861 he was honored with the degree of D.D. from the State Uni-versity of Indiana. Some years later throat trouble compelled the Rev. Dr. Ledoux to give up preaching and led him to establish a school for boys, known as the Storm King School, above Cornwall, on the slopes of Storm King Mountain. As a boy Albert Ledoux roamed the woods of Storm King and became deeply attached to this .wonderful hillside, commanding as it does an extended view of Newburgh Bay to the north and the remoter reaches of the Hudson. In his later years he built his home on its slopes and continued to roam its woods for his recreation. In later years, also, the writer used to look each October for the fringed gentian which Dr. Ledoux gathered in some secret nook to wear in his lapel. In the Storm King school, Albert Ledoux and his brother Augustus Damon, seven years younger, were educated and entered the School of Mines of Columbia College.

Jan 12, 1923

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Jan 1, 1946