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By R. B. Gilmore

It has been the custom of the Railroad Commission of Texas to hold hearings each month with respect to existence and imminence of waste of oil and gas in Texas and its prevention, and to issue orders restricting the production of oil to the reasonable market demands and allocating production to the various fields in Texas. The practice of designating the actual days during the month on which wells are to be shut down was discontinued in the order for November 1942, and orders issued thereafter contain only the number of shut-in and producing days for the month. Orders issued by the Railroad Commission are divided into two main subdivisions, the first a general shutdown order of all oil wells in the various fields in Texas, and second, the exception of certain fields to this general order. Table I shows the producing days for all of the fields in Texas for 1944 under the first of these classifications : The fields that have producing schedules varying from the general order may be divided roughly into three subdivisions, as follows: Table 2 shows the producing days for certain fields that were prorated as a group throughout 1944. Other fields which were occasionally included with this group were also prorated under the general order and by special orders. The producing days for these irregular fields are shown in Table 4. In Table 3 are listed fields that were exempted from any shutdown days during December 1944, the majority retaining this exception throughout 1944. Certain fields included in the general order were added to this group on the first day of the month shown.

Jan 1, 1945

By A. J. Pearce

MOST mines have a model of some kind to illustrate either geological structure, mining operation, or some special condition or feature of the property. The type used depends on the particular feature or use for which it is intended. At Dome Mines we have developed an interesting and practical application of the horizontal-type model. This model shows the workings of each level horizon plotted on glass. These glass panes are set in frames which, in turn, rest on drawers equipped with rollers which can be pulled out as desired into a light chamber. The features of this model are its rigid steel construction and that any desired number of level plans can be pulled out, eliminating any other interference from other levels. Figures 1 and 2 are photographs of the model cabinet and show its construction and general features. The cabinet is of steel construction with the following overall dimensions: width, 6 ft. 5 in.; depth, 6 ft. 7 in.; height, 5 ft. 2 in. When not in use it can be completely closed-in, making the cabinet practically dustproof. There are 30 drawers, one for each of the 29 levels and one for the surface. The glass in each drawer is divided into two panes, 36 in. by 36 in., of flatdrawn double-diamond 'lustraglass' with about l/32 in. between adjacent edges. The panes are held rigidly in the frames, which are lined with felt strips, and may be adjusted by set screws, four of which on each drawer are shown in Figures 1 and 2. The level workings, on a scale of 1 inch equals 100 feet, are traced in ivory black Windsor & Newtons artist oil paint. Co-ordinate lines are shown in crimson lake, and main geological contacts are shown in their respective colours. Figure 3 is a photograph looking down on one of the levels. The lighting consists of 14 30-watt fluorescent bulbs, with reflectors, under frosted glass. These lamps are much more satisfactory when operated by 60-cycle rather than 25-cycle and, as we had available nearby a source of direct current, this was used. The electrical unit consists of a rotary converter from d.c. to 60-cycle. This arrangement gives perfect lighting, allowing most colours to be easily distinguished. Figure 1 was photographed using this source of light, Figure 2 using an outside floodlight.

Jan 1, 1945

By E. W. Newman

DURING 1943 and 1944, there was an urgent need for certain grades of optical calcite (Iceland spar) for instruments for military uses. To find a supply of this material, prospecting was carried out in Montana, California and Colorado. Although some production was obtained by the work in California, the best results were from prospecting the large calcite veins of south central Montana. The bulk of the optical calcite mined during World War II has come from that area. The Bureau of Mines took an active part in the search for optical calcite in Montana. It examined most of the known calcite veins in the 70-mile distance between Wilsall, on the Shields River, and Absarokee, on the Stillwater River, and conducted exploration on several of the deposits. The Geological Survey also took an active part by mapping many of the veins. Actual mining of the calcite was performed at first by Calcite Operators, Inc., and later by the Metals Reserve Co., through an agent. A sorting plant was established at Clyde Park, where custom material could be sold. These activities stimulated mining by private operators. To be suitable for military uses, the calcite mined had to meet rigid specifications as to both size and quality. Individual crystals had to be clear and transparent and if in the form of rhombs had to measure at least 7/8 in. on each edge. Some color and a few inclusions in the calcite were allowable, but material with incipient or developed cleavages, or showing twinning other than parallel to the base, was unacceptable. HISTORY OF DEPOSITS The existence of large veins of calcite in south central Montana has long been known, and for many years the farmers of this region have used the common vein calcite for producing grit for chicken feed. According to reports, the first optical calcite produced from Montana came from the Cartwright deposit near Greycliff,1 but until recently the mining of optical calcite in Montana has been limited to spasmodic searching for small crystals suitable for making nicol prisms for saccharimeters and microscopes, or for mineral specimens. The possible need of substantial amounts of optical calcite for military uses began to appear late in 1942 and early in 1943, therefore the Polaroid company began searching for a source of supply in Montana and California. Work on the Wade property near Clyde Park was started on a small scale in the fall of 1942, by A. H. Hansen, of Clyde Park. During the winter and spring of 1943, a modest quantity of optical calcite was mined and shipped to the Polaroid Corporation, Cambridge, Mass. Most of this was produced from the "Hansen vug," which was found close to the surface. Early in the summer of 1943, mining on the Wade property was undertaken by Calcite Operators, Inc., a company organized for mining optical calcite from the Montana and California deposits. This com-

Jan 1, 1945

By V. L., McCutchan

FORM of ore bodies, strength of wall rock, and quantity of water that must be handled differ so greatly in the various districts in which the Corporation operates that a variety of mining methods have to be employed. All are underground, however, with the exception of glory holes at Cerro de Pasco from which siliceous silver pacos ore is obtained. In general, the ors is in many relatively small bodies unsuitable for hulk mining, such as caving or top slicing. The strength of the rock and ore rarely permit open stopes, though shrinkage is successfully used on various veins with strong walls, particularly in, Casapalca. Horizontal cut and-fill and square-set stoping with careful filling are the principal methods employed, with the necessarily higher cost for supplies and labor offset as much as possible by care in the avoidance of dilution. The mines at both Morococha and Casapalca are notoriously wet, and even at Cerro de Pasco the quantity of water was enough to retard deep development until the perfection of electric pumps. In Morococha particularly, the extension of successive levels, first from adits of moderate length, then from shafts and heavy pumping installations on the 750 and 1000 levels, and finally by the 30,564-ft. Kingsmill tunnel, was one of the most difficult and long continued fights against water and resulting heavy ground that is recorded in mining history.

Jan 1, 1945

By Howard C. Dunkle

Various factors can affect the quality of B1112 and B1113 steel as produced in a bessemer plant; among them: vessel-charging practice, blowing practice, ingot-pouring practice, ingot delivery-time practice, pit-heating practices, and ingot-rolling practice. Evaluation of the influence of ingot delivery time on quality has been chosen as the subject for this paper because this time is completely within the control of the operator, and on this particular factor there is a tremendous amount of information in the dusty archives of the average steel plant. In order to know how much improvement can be made and when attention should be directed to other factors that influence quality, in the continual struggle for improvement, the effect of ingot delivery time must be accurately evaluated. Once this is done, the importance of other variables can be accurately obtained, thus eliminating the necessity of resorting to opinions that are of doubtful value at best. In the study described herein, extensive use was made of the statistical card system as a method of determining the effect of ingot delivery time as a quality factor in bessemer screw-stock grades by simple direct correlation. The value of this statistical method as a means of accurately determining the influence of various factors has been amply demonstrated by Work1 for the bessemer process and by Hand and Gould2 and Fetters and Chipman3 for the open-hearth process. The quality records of 300,000 tons of bessemer screw-stock billets were used in this study of the effect of ingot delivery time on the rejections for breaks, pipe, check and seams. The reduction in the number of rejections for poor quality reduces the costs and increases the productivity per man-hour. The operator today, more than ever before, must know how to keep costs down, how to do it most quickly and in the best way, and how to obtain the highest quality in line with the ever increasing demands of the customer. It is necessary for him to know the individual relations and interrelations between various factors affecting the quality of the manufactured product if he is to produce material that will meet competitively the cost, performance, and quality demands of the trade. SIGNIFICANCE OF STEEL MANGANESE, MIXER SILICON AND STEEL SULPHUR AS QUALITY FACTORS In order to obtain the highest grade of material it is necessary to control many factors-not just one or two, as operators

Jan 1, 1945

By R. A. Pallanch

IN his recent paper, "The Controversial Art of Flotation," (Mining Technology, March, 1944) E. H. Rose states that "flotation is a science in so many variables that only art can blend them." This statement is apt. It contains meat. In other words, a valid scientific reason is behind every flotative effect. Some of these reasons we understand, but much the greater number of them still escape us. This does not prevent us from "going places," as familiarity and experience with the problems result in an increasingly intelligent and artful handling of these effects. Hypotheses are built up by the individuals concerned to explain certain happenings. Many of these hypotheses have to be abandoned when placed under the glaring scrutiny of actual trial. A few survive the severest of tests, come through unscathed, and are elevated to the rank of theories, something susceptible of certain chemical and physical explanation, under the conditions of the particular plant concerned. If these theories continue to hold water under all the variations existing in most milling plants, they gradually become accepted as facts in the minds of the plant operators. But-and here is a big BUT-these so-called facts may fall down completely in another plant working under an entirely different set of conditions. In other words, each plant tends gradually to build up its own facts, which may or may not be facts at another operation.

Jan 1, 1945

By Clyde Williams

IN this war as in no former one, the use of metals has been the major factor governing success. For building new plants, new transport facilities whether by land, sea, or air, for our mechanized army, and for nearly all weapons, iron and steel has provided the basic material. Being the world leader in iron and steel production in peacetime, we soon adapted plants to production for war. Starting with a production of 66,000,000 tons of steel ingots in 1940 from a rated capacity of 80,000,000 tons which only could be reached by straining every productive device available, our industry expanded to 86,000,000 tons in 1942, and ultimately to 96,000,000 tons. To do so required expansion of every unit operation including mining, rail and water transportation, blast-furnace and steelmaking facilities, and rolling mills. New plants not only had to be built in record time but more output for each operation was essential. This performance required skillful operation and engineering techniques and also a better understanding of the physics and chemistry underlying such complex operations as the working of a big blast furnace. A vastly increased pig iron production made possible the great output of steel by an industry that had depended on scrap for its basic raw material even though sufficient scrap was unavailable. This was done by conversion of pig iron in the Bessemer either into steel or into a low-carbon product that was subsequently used in place of scrap in the open¬hearth steel furnace. Furthermore, by duplexing from the open-hearth to the electric furnace, and the construction of many new electric furnaces, our output of electric-furnace alloy steel was greatly increased. Moreover, techniques were developed by which alloy steel could be made in the open hearth with the result that our production of alloy steel reached the fantastic figure of 15,000,000 tons a year.

Jan 1, 1945

By D. S. Sanders

IN the four mills of the Cerro de Pasco Copper Corp. in Peru, some 3000 tons of complex sulphide ores are treated daily, with four kinds of concentrates produced: copper, lead, zinc, and pyrite, each containing values in silver, gold, bismuth, and some other metals. Copper occurs in the various ores as chalcopyrite, enargite, tetrahedrite, tenantite, bournonite, and chalcocite; lead as galena; and zinc as sphalerite and marmatite. Small amounts of silver and tungsten minerals are also present. The gangue consist mainly of shale, quartzite, calcite, rhodochrosite, pyrite, and pyrrhotite. In general the values are freed with a relatively coarse grind, about 70 prr cent minus 200 mesh being the finest to which the pulps are ground. In Morococha and Casapalca however. sphalerite particles much finer than this contain inclusions of chalcopyrit r. At Cerro de Pasco the silver and gold are present in all sizes of the ground pyrite.

Jan 1, 1945

By T. R. Wright

THE Corporation operates concentrators in four camps: Casapalca. Morococha, Cerro de Pa-co, and Mahr. The present concentrator at Cerro de Pasco is the newest having been completed in 1943. and that at Casapalca the oldest, having been built originally as a gravity concentrator, in 1889. Prior to 1925 the Corporation's milling operations were confined to the beneficiation of silver-bearing copper ores, and treatment of these ore: by flotation was started in 1918. Although fairly large deposits of complex, fine-grained lead-zinc ores existed, little progress had been made in the treatment of such ores--in Peru or elsewhere-until the early 'twentics. The Casapalca concentrator began the selettive concentration of complex leadzinc ores by all-flotation methods in 1925, or contemporaneously with the commercial development of selective lead-zinc flotation in the United State:.

Jan 1, 1945

By NEWTON B. KNOX

CHILEAN mining in the public mind is rightly associated with copper. Chuquicamata with its great hill of copper-bearing granodiorite as well as Sewell and Potrerillos with mineralized volcanic necks together can supply a good proportion of the world's normal necessities of that metal. Chile is an extremely long and narrow country, averaging only 109 miles wide. Its eastern frontier is the Andes and it is on the western slopes of these mountains that the great copper deposits have been discovered. West of the Andes a great longitudinal depres sion has permitted accumulation of nitrates and other soluble salts in the arid north; in the north center it is hidden by a series of cross ranges, but in the center a moderate rainfall makes it the country's most important agricultural region. In the south this depression is drowned and gives rise to a series of straits and fiords. This enormous cleft in the earth's crust is separated from the sea by a coast range of moderate elevation which in the south is represented by a series of islands and mushroom-shaped peninsulas

Jan 1, 1945

By George A. Miller

ALTHOUGH the Andean mountain belt, which contains almost all the metal deposits of the other South American nations, does not enter Brazil, this country is rich in mineral resources, for in area it accounts for half the continent and geologically it contains almost all of the Brazilian Shield. This great mass of ancient rocks has been relatively stable for a long time and forms a great area of plateaus and highlands interrupted only by the syncline which carries the Amazon River across it to the sea. Lowland Brazil - the great flood plains of the Amazon. Tocantins, Paraguay, and Parana Rivers-is of no interest to the miner, and in fact supports but a small proportion of the country's population. The highland area is divided into unequal parts by the Amazon River; the north half is underlain by the north lobe of the Brazilian Shield which extends into Venezuela as far as the Orinoco, and into the Guianas, and is known as the Guiana Highlands. Mineralization appears to have been weak in the Brazilian portion of these hills. In fact most of the ore deposits are to be found in the States of Minas Gerais and Bahia, although the neighboring states of Sao Paulo, Pernambuco, and Piauhy can also boast of some deposits. Goias and Matto Grosso are as yet incompletely prospected but are considered to contain reserves for the future.

Jan 1, 1945

By L. E. Young

IT has been said the British Empire was built on British Coal. In all the postwar planning for Great Britain the necessity for producing cheap coal and the prosperity of the coal industry are given first consideration. On Jan. 23, 1945, there was released in London a "Report to the Colliery Owners" which had been awaited with great interest. This was entitled "A Plan for Coal" and was the recommendation of Robert Foot, chairman of The Mining Association (Colliery Owners), prepared at their request. Presentation of the "Plan" at this time is particularly significant as it is an answer to the demand for nationalization of the coal industry by the Labour Party and at the same time is a carefully considered program for postwar reconstruction, prosperity, and stability. In the words of Mr. Foot, If the coal industry for the first ten years after this war is to find itself in a situation similar to the one it occupied for the ten years following the last war, with its record of disputes, strikes, stoppages, short-time working, unemployment, and, with it all, a completely insufficient margin of profit, and all the insecurity and instability in our basic industry that was brought with them, it is goodbye to any real prospect of full employment, social security, and high standard of living. To present an elaborate review of the conditions which have brought to a crisis the unfortunate situation in the British coal industry is here unnecessary, but certain of the salient points

Jan 1, 1945

By George A. Miller

AMERICANS like engines, but more than anything they like powerful engines, and next to that they want them quiet, silent, smooth; perhaps a slight purr might be permitted, but they must not knock. To provide a gasoline to fit all these requirements, American petroleum technologists have experimented for years, and mounting octane numbers of the gasolines the refiners have produced both before and during the war bear witness to their success. The question on everyone's mind now is what may we expect in the way of engine fuel in the postwar period? The gasoline drouth during the war rationing, the inconvenience of doing without a car were major annoyances to all motorists, but they put up with them pretty cheerfully for the most part. However, now that the war is over, and the jalopies are all out and the better cars have been taken off the jacks and brought out on the road, the call is for "Some of that good gas-fill her up, if you please."

Jan 1, 1945

By Parry. V. F.

"SUMMARY This report reviews the status of the packaged-for industry as of 1941. A field study was made of 35 representative plants to obtain technics and economic data on different types of processes used to make packaged fuel in the Central States. The report includes a classification of processes, photographs of typical operations, designs of different plants, an analysis of costs of manufacture, and a study of the physical and chemical properties of fuel cubes.It was observed that many of the smaller plants were having troubles in the manufacture of packaged fuel as the price of materials and costs of labor advanced toward the higher levels of 1942. In some instances, the total cost of manufacture was as high as $5.00 per ton, while in the better, medium-sized plants it was approximately $3.25 per ton. The direct manufacturing costs, excluding investment and depreciation, ranged from $3.17 to $2.37. These costs permit almost no profit at small plants when packaged fuel sells for the same price as competing lump coal under conditions existing in 1941-42.It was found that the predominant troubles in plants were due to inadequate drying and insufficient mixing of the starch binder. It was ob¬served that in the better plants, where proper mixing of binder was attained high-quality packages were made if 50 to 70 percent of the moisture was removed in the drying ovens. Experimental data obtained in the laboratory show the relationship between the temperature of dry air and the time required to remove different percentages of moisture in wrapped orunwrapped coal cubes.The average physical and chemical properties of fuel cubes made by five processes are listed, and tentative standards for minimum physical qualities and methods for measuring quantity are giver."

Jun 1, 1944

By Raymond S. Weimer

Of the several characteristics of a coal that influence its suitability for use in a given piece of burning equipment, the clinkering and slagging characteristics of the ash of the coal are highly important. They determine the maximum rate at which the coal may be burned on a stoker or in pulverized form without difficulty from damage to metal parts, from erosion of refractory walls, or from stoppage of gas passages by accumulation on the tubes. They also determine the minimum rate at which a slag-tap furnace may be operated without difficulty in removal of the ash in fluid form. Need for a Better Criterion In common with other producers and users of coal, the Northern Illinois Coal Corporation has long used the available methods for the measurement of the clinkering characteristics of coal ash, chemical composition and fusion temperature of the ash, as criteria for the selection of coal that would suit the particular requirements of its customers. These two available criteria have greatly helped in the problem of selection but it is unnecessary to dwell upon the fact that they are not completely adequate for the purpose. The composition of the ash and its clinkering tendency vary widely over the company's mining area. In a certain period, some years ago, an unusual amount of severe clinkering of the ash of coal shipped made extremely acute the need for a better criterion of the clinkering that might be expected. It was also desirable that the criterion result from a reasonably rapid method, so that the clinkering characteristics of the coal would be known before shipment. Complaints on the severe clinkering of the ash came from only a fraction of the output of the mine but the occurrence of the clinkering seemed quite unpredictable. Attempts to relate the chemical composition of the ash and the fusion temperatures to the clinkering were unsuccessful. Coal from the area of the mine in which the fusion temperature of the ash was the lowest gave the least trouble from clinker-ing. Chemical analysis of the ash from that section giving the most trouble showed high contents of iron and low contents of silica, but frequently these were not greatly different from those of coals that gave little trouble from clinker. Aside from the clinkering difficulty, the coal was quite satisfactory. The ash content was normal and high rates of burning could be obtained, but again and again such severe clinkering would occur that the furnace would be shut down because of the accumulation of clinker. Examination of the clinker from the customers' plants showed that the clinkers that adhered to the grates and fouled the fuel beds were hard, flat, dense, and usually dark in color. Coal that was satisfactory gave clinkers that were softer, bulky rather than flat, of low density, and usually lighter in color.

Jan 1, 1944

By I. M. Roberts

The war emergency has affected every phase of industry. The gas and coke-oven companies have sought faithfully to discharge their responsibility in this critical period and have willingly modified their operations where possible to meet the ever increasing demands made upon them. Our company made commitments for blast-%urnace coke for war purposes which necessitated a reduction in coking time in order to produce the amount required to meet the new demands. At the same time there were certain customers of long standing, who had been supplied with foundry and egg-sized coke produced on fairly long coking periods, who also were engaged in war work and whose patronage we desired to retain. Coke produced on short coking rates from the coal mixture we were then using would not have been satisfactory for these customers. The average width of our ovens is 19¾ in., which is a little wider than the more modern ovens of the present day. They were originally designed to give somewhat cool tops in order to produce a rich gas. This necessitates carrying the heats a little on the warm side so that the tops will be fully carbonized. A reduction in coking time, as is generally known, is accompanied by a reduction in the average size of the coke produced. This is due to the greater shrinkage that takes place at the higher temperatures required to carbonize the charges in a shorter time. The net result is that the coke is more cross fractured and longitudinally fractured and breaks up into small sizes on handling. The cokes produced from the better coking coals seem to be more susceptible to fracture at high temperatures than those from poorer coking coals. A coal mixture that produces a beautiful foundry-sized coke at 30 to 36 hr. may yield a product at 18 hr. that would be so badly fractured as to be unsatisfactory for foundry practice. Coking Characteristics OF Coals Our problem was to find some economical innovation and develop a method that would enable us to reduce the coking time and still produce a coke satisfactory to our foundry trade. However, before discussing the results of our present operations, it might be well to present a few observations on the coking characteristics of coals in general. Most coke-oven operators carbonize a blended mixture of coals. It may consist of a single high-volatile coal with a single low-volatile coal, or of a combination of several high-volatile and low-volatile coals. Medium-volatile coals of the Eagle seam are used for the production of high-grade foundry coke. Medium and high-volatile coals are often blended with one or more low-volatile coals. The possibilities are almost infinite, but the combinations are limited by such factors as cost and facilities for handling multicoal mixtures, and by other practical considerations. Every coal has characteristics that make it blend better with a particular coal or coals in preference to others. This property has

Jan 1, 1944

By R. A. Wagstaff

SINCE the time of the early Egyptians, the use of copper has been a boon to the life of most of the civilized world. Its use has been varied; in many connections, the art by which it attained its greatest usefulness has been lost. In this paper an endeavor will be made to take into consideration some of the many changes that have occurred during the last 40 years of copper-smelting operations. During that period the copper blast furnace has been almost forced out of existence by new methods of ore concentration-first, gravity concentration, and then flotation. These new methods of concentration introduced many new factors into the metallurgy of copper. The product was wet, it was fine and it was high grade. To overcome all these factors many changes have been necessary throughout the smelting agenda. New equipment has been necessary for transportation, unloading, sampling, bedding and moisturing in all smelting plants, especially the custom smelter. During the early days of "flotation," little was known about filtering or the use of an alkaline circuit; often the concentrate going to the smelter contained 20 to 25 per cent moisture. It is easy to imagine the difficulty arising with a product of this nature when it had to be shoveled by hand labor. To meet these conditions, mechanical unloading and sampling devices were soon developed. In many instances such good progress was made that actual costs for handling this unfavorable product were lower than those formerly incurred on the old product. Today most sampling of copper ores and concentrates is being done by mechanical sampling, pipe or augur sampling, or shovel sampling. Where concentrates are uniform in metal content, a great many of the plants now use pipe or augur sampling. For spotty ores, the old shovel sample with cone and quartering during the final stages is still in use. Where big tonnages are handled, mechanical sampling of concentrates is being done, with satisfactory results. To curtail slow and tedious cutting and mixing procedure, mechanical mixing boxes, splitters and cutters are used to cut down labor costs. MILLING As crude ores become scarcer, the use of milling operations increases. The few crude ores that are still smelted are used as fluxing types. To use these ores finer grinding has been found advantageous. This has made for better bedding and fluxing conditions, which in turn makes for faster smelting, lower fuel consumption and better metal recovery. The degree of fineness is more or less determined by the nature of the product. Most plants have set a standard of through ¾ -in. mesh screen for roaster- reverberatory smelting and through ¾ in. mesh screen for converter fluxes. For some refractory ores; even finer grinding has been found to be advantageous for good reverberatory smelting.

Jan 1, 1944

By E. S. Wheeler

The conversion plant of the Clirnax Molybdenum Co. is at Langeloth, Washington . County, Pennsylvania, approximately 30 miles west of Pittsburgh. The molybdenite concentrates converted originate in the company's mine and mill at Climax, Co1orado.l They are delivered to the Langeloth plant by rail packed in 175-lb. bags. War production of concentrates at the mill started in 1918 but it was not until about 1920 that any peacetime uses of the metal began to develop. Early conversion of Climax concentrates was mainly into ferromolybden um, produced for the company by a custom smelter. Chronology of Plant Development In 1924 a small hand-rabbled roaster was built at Langeloth, the roasted concentrates being used principally in the production of calcium molybdate by a conventional wet method. The size of the original plant is indicated by the fact that during 1925 about 400,000 lb. of molybdenum was converted. In 1925-1926, a multiple-hearth roaster was erected (12-ft. 0.d. 8-hearth Nichols-Herreshoff); also the first experimental ferromolybdenum was produced at Langeloth. At this time sa.1cium molybdate was produced in the furnace by a process to be described. With continued interest in and increased use of molybdenum, it was necessary to arrange for enlargement of plant facilities. Although only one 12-hearth 16-ft. 0.d. roaster was erected at this time (1929), plans were prepared for a duplicate unit, which was completed in 193 5, giving a potential roasting capacity of some 16,000 lb. Mo per day under the then prevailing roasting practice. Shortly after this second unit had gone into production, increased demand overtaxed the plant, and as a result two 12-hearth 18-ft. 0.d. roasters were placed in operation in 1936 and 1937. This gave the plant a potential roasting capacity of 40,000 to 50,000 lb. Mo per day, and necessitated major changes in auxiliary handling equipment as well as improved facilities for producing ferromolybdenum. Following the introduction (1938) of a new product—molybdic oxide briquets— and because of the constantly growing demand for molybdenum, plant facilities were again enlarged in 1940 and 1941 by the erection of two 16-hearth 18-ft. 0.d. roasters. These two new units, along with a change in roasting practice, brought the potential roasting capacity to 150,ooo to 190,000 Ib. Mo per day, based on about 15 lb. per sq. ft. of hearth area. Other departments of the plant have necessarily grown, until today the plant is modern throughout and completely mechanized, with equipment geared to produce marketable products as follows:

Jan 1, 1944

The reconstruction of the world after the present war must inevitably be profoundly influenced by the rise and progress of New China.The principle of Chinese mathrity has been admitted by Great Britain and the United States by their abjuration of extra-territorial tights, and by the withdrawal of the Maritime Customs Administration. The United States admits equality by her declaration that Chinese are eligible for American citizenship, and the reaction to this will be swift enmity to such peoples as may impose humiliating restrictions upon Chinese citizens.Finally, the decisions of the Moscow Conference and the recent meeting of National leaders in Cairo give partnership rights to this new State in post-war reconstruction, and open the way for a rapid realization of her destiny.It seems certain that China, if so she wills, can become, within a generation or so, one of the considerable forces of the world. The toad she wiII follow will be lighted by her own inherent and intrinsic genius. Her speed of progress can no longer be forcibly influenced by other nations and the attitude towards her of somewhat contemptuous patronage hitherto adopted by the European communities bordering the Pacific Ocean must be radically modified.It is doubtful whether the European will ever reach full understanding of Chinese mentality. The Chinese "way of life" since the dawn of her civilization has been totally divergent from that of the European, but the enormous potential strength, due to the simplicity of their requirements and their steadfast industry, is a function of that "way of life." On the other hand the trend of reorganization must obviously be towards Western standards; and a wide knowledge of the potential strength of the Chinese is possible and will be essential in our post-war world. The following, necessarily inadequate, notes are therefore offered, as an indication of the obstacles to be overcome and the capacity of the Chinese executives and operatives to overcome them.For 'thirteen centuries the political and social structure of China proper (ie, excluding Mongolia, Manchuria and Tibet) has been rigidly shaped by the philosophy of Lao Tze and the ethics' of Confucius. This Taoism, which is described as the "way of harmony" with its three jewels of character, gentleness, economy and humility, advocates the minimum of social, economic and political organization and still gives the key to the Chinese character.The Mongol and Manchu conquests of the 12th and 17th centuries, respectively, could hardly be dignified with the name of war, but the superior intelligence and harder mentality of the unwarlike Chinese finally absorbed...

Jan 1, 1944

By H. H. Claudet

PROBABLY the first flotation mill for treating molybdenite ores was put into operation .in Norway during 1913, when the writer was employed to introduce and apply the Elmore vacuum flotation process at a mine in southern Norway. These operations proved successful and led to other similar installations in that country. It remained, however, for Norwegian engineers themselves to iron out their difficulties and establish the molybdenum industry on a basis which ultimately attained world importance. Just as today, an urgent demand for molybdenum arose during the world war of 1914-18. By 1916, many molybdenite properties were in operation in Canada and several small concentrating mills were under construction. At one of these, in the Ottawa Valley district, the opportunity came for applying the Elmore vacuum flotation process, using a flow-sheet similar to that adopted in Norway. Later, as one of the staff of the General Engineering Company, who had already developed a highly efficient flowsheet for treating molybdenite ores, using the Callow pneumatic flotation process, the writer devoted considerable time to research work and investigations on a number of molybdenite projects and deposits in eastern Canada. The bulk of Canada's production of molybdenite was coming at that time from the Moss mine at Quyon, Que., where concentration of the ore was effected by water-film flotation. It is of interest to note that this process, based on the principle of surface tension, had been developed and introduced by the late Henry E. Wood, of Denver, Colorado- one of the original owners of the Moss mine-at the time he was investigating the Elmore vacuum process in his Denver plant. The process, with certain modifications, was used at several other properties in eastern Canada, and notably in the ore dressing laboratories of the Department of Mines at Ottawa and in a plant at Renfrew, Ont., in both of which ore from deposits in various parts of Canada was treated, with recovery of very appreciable amounts o much needed molybdenite. During the summer of 1917, the water-film flotation mill at the Moss mine was dismantled and the plant was re-modelled by the General Engineering Company to include the Callow system. This installation, using improved flotation methods, was highly successful both as to recovery and grade of concentrate, and proved a decided advance in molybdenite concentration, a recovery of upwards of 90 per cent being obtained, with a concentrate grading over 90 percent MoS2.

Jan 1, 1944