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HAVING produced one ton of concentrate that contains the copper that can profitably be saved or recovered from anywhere between 3 and 60 tons of mine ore, the ore-dressing engineer passes the result of his handiwork over to the metallurgist for smelting. Essentially, the concentrate is a damp mass of finely ground material consisting of copper sulphide minerals; pyrite, the sulphide of iron; and gangue, usually silica and silicates of aluminum. The purpose of smelting is to produce metallic copper and a slag containing the iron and siliceous constituents by pyrometallurgy-the kind of metallurgy that employs fire and heat to produce the chemical reactions through which it attains its object. Though blast furnaces have been used to smelt Porphyry-mine concentrates, notably at Braden, more than 90 per cent of [ ]

Jan 1, 1933

By AIME AIME

BEFORE proceeding with the papers scheduled for the ore and foundry session*, the teller's report on the election of officers for the ensuing year was presented, a; follows: Chairman. G.C. F. MacKenzie; vice-chairmen, C.S. Robinson, J. T. MacKenzzie, C. E. Meissner; executive committee, A. L. Field, R. F. Harrington, E. F. Kenney lit. Waterhouse announced that the fall meeting will be devoted to alloy steel. This meeting will be held in Chicago the week of Sept. 22 in connection with the National Metal Congress. He also announced that oxygen in steel will be the central idea of the meeting which will be held in New York next February. The first paper, entitled "Sintering Limonitic Iron Ore at Ironton, Minn.," was presented by Perry G. Harrison (T. P. 284), the author. Sintering was first un¬dertaken in 1024 to treat Cuyuna range iron and manganiferous ores low in silica and high in moisture and containing objectionable qualities of fine... A Dwight-Lloyd machine was first installed. This machine was replaced by a larger one having a width of 72 in. The power cost was decreased from about $11.22 per ton of sinter on a 42-in. machine to about X0.14 for the 72-in. machine. The tons of sinter per man-shift was increased from 11.86 to 16.77. Improvements embodied in the larger plant reduced the cost of sintering to $0.41. The analyses of iron ore and manganiferous ore and the sinter produced from these materials was used to show the increase in value at the mine resulting from sintering. Crude iron ore actually unsalable was increased in value f.o.b. mine from a theoretical figure

Jan 1, 1930

By J. M. Camp

In conforniity with the design of the oficials of the United States Steel Corporation for the standardization of the methods employed in the sampling and analysis of all materials encountered in their various lines of manufacture, the Chemists' Committee presents this compilatioti of standard methods for the sampling and subsequent analysis of molten pig-iron. In selecting the methods, the Committee employed the same line of procedure as in former cases, viz., the careful consideration of all the methods employed in each laboratory of the Corporation, evolving therefrom the several methods herein described, the immediate adoption of which is desired. The services of Messrs. W. B. N. Hawk, William Brady, and C. H. Rich, a sub-committee appointed for the preparation of the present paper, are gratefully acknowledged. II. Introduction. A quite obvious cause of nonconformity of results of comparative analyses in the various laboratories of the Corporation has been an apparent lack of uniformity of method in the sampling and analysis of molten iron. This condition is particularly apparent with regard to the determination of the sulphur, numerous discrepancies in which would appear t.o indicate the absence of, and the necessity for, some uniform method of procedure. The estimation of the

Jan 1, 1913

By Harry V. Welch

This paper presents a brief discussion of numerous devices and processes which have been utilized for the recovery of values from gases in copper reduction works and describes in greater detail the development and application in recent years of electrical precipitation, more familiarly known as the Cottrell process, to the problems of dust losses with furnace gases in copper-smelting and refining plants. The field for collection of suspended particles in gases is widely extended in our modern complex, congested .and industrialized mode of living, and its satisfactory solution is required by our increasing appreciation of the extravagant waste, unhealthful effects and nuisance which such uncontrolled emission of solid suspensions represents. Much of the special dust-recovery equipment in use today has been developed in one industry and carried over to many others. The early work of Cottrell was with sulfuric acid mists, aimed at the purification problem in contact acid manufacture, but the present uses of Cottrell equipment cover a diversified field—carbon black, combustible gas, oil mists, iron blastfurnace fumes and dusts, cement-kiln gases, as well as the purification of gases in contact and chamber acid plants and its wide and extended use in the nonferrous metallurgical field of copper, zinc and lead, and their associated metals. Dust and fume collection from furnace gases became a problem only with the modern development of large and amply powered auxiliary furnace equipment, which in turn permitted large furnace units, fast driving and large outputs of finished product per unit of furnace capacity. The ancient metallurgist with his small clay pot and hand-operated bellows had too little gas velocity to cause a real dust loss. As furnaces grew in size, flues and stacks were added, and undoubtedly the first observable dust losses were indicated by the deposits in the flue and stack base. Large flues, it was noted, collected more than smaller ones, and the expansion of a portion of the flue into a chamber represented the first serious attempt at recovery of furnace dust losses. For a century or more the settling chamber represented the best of skilled metallurgical practice in recovery of furnace dust, and it may be said to have reached

Jan 1, 1934

By H. E. Dunn, C. M. Cosman, J. H. Brennan

Up to the beginning of World War I, the American ferro-alloy industry was in its infancy and largely dependent on Europe. During that War, capacity was over expanded. Later recovery and commercial and scientific development have resulted in an industry which in 1957 produced 1.8 million tons of ferro-alloys. THE ferro-alloy industry is today an important element of the industrial structure of the United States. Its output is valued at almost half a billion dollars annually and its products are basic not only to National defense but also to the peacetime standard of living. This has not always been so. The ferro-alloy industry from late in the last century has grown from small beginnings, nurtured by the demand for stronger, tougher materials; by the search for steels capable of absorbing severe impact loads and resisting corrosive media and high temperatures; and also by the need for electrical and electronic specialties. Conversely, the ferro-alloy industry has grown because it developed improved steels and alloys by extensive research, and because it was able to show to steel makers the advantages accruing from the more extensive and the more economical use of alloying elements. The industry has grown in scope from producing a few grades of ferro-alloys of the more common metals-manganese, chromium, vanadium, silicon, titanium, tungsten, and molybdenum-until there are today some 150 compositions of ferro-alloys available to the steel maker, including such elements as columbium, zirconium, and boron. In 1912 the industry produced 360,000 tons of alloys valued at about $12,000,000, while 1957 production figures show an output of 1.8 million tons worth $440,000,000. In the United States, the history of an industry is largely the history of the companies making up this industry; hence, this paper will briefly trace the development of the most important ferro-alloy-producing companies. Quite varied have been the reasons that caused the different companies to move into the ferro-alloy field; the Willson Aluminum Co., seeking methods of producing aluminum, succeeded with the production of calcium carbide, and their developing electric furnace skills led them to the production of ferro-silicon and ferrochromium alloys. Willson was the predecessor of the Electro Metallurgical Co. of Union Carbide. Two Pittsburgh undertakers, interested in vanadium as an alloying agent for steel, set about to find a mine and, ranging as far as Peru, fathered American Vanadium Co., the predecessor of Vanadium Corp. of America Experiments of the

Jan 1, 1961

By Charles Macdonald

It may seem to be almost unnecessary to occupy the time of the Institute in further consideration of a question which has been so comprehensively treated in papers already on file in our own Transactions and in those of the American Society of Civil Engineers. Unfortunately, however, the results of these concerted efforts have not been materially to increase our stock of Knowledge in the direction sought for; and as the necessity for this information is becoming.more and more apparent as the demand for structural materials increases, it is believed that by continuing the agitation by means of discussions in this and kindred societies, whose members are vitally interested in obtaining reliable data as to the properties of the materials they are called upon to work with, public opinion may be educated up to the importance of exerting such an influence upon the law-makers of the country as will result in the formation of a competent board, with adequate means at its disposal, to carry out this great work in a manner alike acceptable to the makers and users of the materials in question. It may be proper in the first place to glance briefly at what has been attempted thus hr, then to indicate some of the more important lines of needed investigation, and finally to consider reasons why government aid may with propriety be sought for in carrying on the work. At a convention of the Society of Civil Engineers held at Chicago June 5th, 1872, it was, on motion of General William Sooy Smith, resolved, that, " Whereas, American engineers are now mainly dependent upon formula for the calculation of strength of the different form of iron and steel, not based on experiments upon American materials and manufacture; and " Whereas, There differ greatly in many of their ch~racteristics front thoae of foreign production, both in their nature and forma: therefore,

Jan 1, 1882

HUDSON MAXIM, Brooklyn, N. Y.-Immediately after the creation of the Naval Consulting Board, Admiral Strauss, Chief of the Bureau of Ordnance of the Navy, told members of the Board that the most important problem for the scientists to solve was erosion in large guns. The Navy, for years, had been working on the problem with marked suceess, but there was much yet remaining to be accomplished. As Chairman of the Committee on Ordnance and Explosives of the Naval Consulting Board, I communicated with several experts in the manufacture of steel, principal among whom was Prof. Howe. He generously agreed to help in every way possible, and the work that he has done and the time that he has spent upon it can he appreciated only by reading his paper. Prof. Howe asked for some rings. from a, certain 14-in. gun which Admiral Strauss had mentioned in particular, and in which, he had informed us, at each shot the bore of the gun, was enlarged about 0.001 in.,' and that after a relatively small number of rounds it was considerably eroded. It has puzzled scientists for a long time to account for the peculiar erosive effect produced by the powder gases in a gun, arid: what Prof. Howe has done in his paper is worthy of Sherlock Holmes. He is a veritable Sherlock Holmes of science.

Jan 4, 1918

By J. R. Long, E. T. Hayes, R. S. Dean, F. S. Wartman

THE production of titanium in 15-1b. lots and with a purity sufficient to be consolidated into ductile metal, as described in a previous paper,1 has provided adequate material for a study of the : physical properties of titanium and a more thorough examination of its working qualities. Data on the physical properties reported in that paper were obtained on metal fabricated by a fixed procedure, standardized for the purpose of control of the reduction, and are representative only of material fabricated under those conditions. There are many possible variables in the working schedule, which will have significant effects on the properties of the finished material; and since the previous working methods were not necessarily the best, an investigation of the fabrication of titanium by other methods was undertaken. In this work the consolidation of the powder by pressing and sintering was conducted essentially as outlined in the report cited' and all efforts were centered on fabrication methods for those powders and the properties produced by them. Hardness, density, microstructure, and tensile properties were determined at various stages in the working and annealing; and resistivity measurements were made on a few bars and drawn wire. [ ] CONSOLIDATION OF THE POWDER The screen analysis of the available titanium powder is given in Table I. No attempt was made to alter the size distribution from that noted because this powder, although coarse by normal powder-metallurgy standards, produced acceptable compacts suitable for the present work. Because of their large specific surface, finer powders are more contaminated by oxygen and produce harder compacts, which are difficult to work. The powder as produced is soft, compresses in a normal fashion, and exhibits very little tendency to adhere to the die surfaces. Unlike aluminum and magnesium powders, it can be readily pressed without the use of die lubricants. When compacted at so tons per

Jan 1, 1946

By Charles Meyer, Reno H. Sales

AT Butte, successive zones of sericitized and argillized quartz monzonite occur around every ore-bearing fracture regardless of its size, attitude, or relative age. The two types of alteration always occupy the same relative positions; sericite adjacent to the ore-bearing vein, clay minerals always between the sericitized rock and fresh quartz monzonite, except where overlap of alteration effects between adjacent fissures has eliminated the lower grade mineralogical products, as is the case in much of Butte's Central zone of pervasive sericitization. As long as active circulation continued in the channel, each zone migrated away from the fissure, that is, it grew at its outer edge and simultaneously receded at its veinward edge because of encroachment by the next innermost zone. The different mineralogical and chemical responses within the wall rocks to the attack by the ore fluid are dependent not on a drastic about-face change of composition of the fluid in the channel relative to its ability to alter the quartz monzonite but on continuously varying conditions of physico-chemical environment within the wall rock outwardly from the vein.

Jan 1, 1947

By J. B. Newsom

IN the September 1936 issue of MINING AND METALLURGY the pioneer work of boring a 5-ft. shaft to a depth of 1125 ft. at the Idaho Maryland mine in California was described. Later, a Bureau of Mines Information Circular (No. 6923) gave additional data. In re¬cent months still further progress has been made in this technique through the sinking of a 5 1/2-ft. shaft for Pickands, Mather & Co. at their Zenith mine, Ely, Minn. The present work was done with new carefully designed equipment and several experienced men so that progress, as shown below has been much better:

Jan 1, 1938

By J. J. Arps, T. G. Roberts

Since the introduction of the relative permeability concept in the middle thirties1,2 various investigators have shown3,10,11,12,15 how the basic equations for the flow of oil and gas through porous media can he utilized to compute the recovery from depletion type or solution gas drive type reservoirs under certain conditions, when the necessary physical data pertaining to the reservoir rock and its reservoir fluids are known. In the study by Muskat and Taylor" in 1945, the effects of viscosity, gas solubility, shrinkage, and the permeability-saturation characteristics of the producing formation on the production histories and the recovery of gas drive reservoirs were analyzed. Each parameter was varied a limited number of times, while keeping the others constant. The work was not carried to the point where the data could be used directly to estimate the primary recovery in those cases where certain rock and fluid characteristics were known or could be assumed. Since the publication of this classic study, the work by Beal in 194616 and Standing in 1952'" has established general correlations of oil viscosity and shrinkage with gas solubility and oil gravity. In addition. a considerable number of relative permeability relationships for different types of reservoir rocks has been published2,5,13,17,19,20. Also, the burden of the numerical work required in the solutions of the differential equation has. during the last few years, been greatly reduced with the availability of modern electronic computing facilities. The purpose of this paper is therefore to present the results of a large number of such recovery computations covering the normal range of variation of the main parameters such as the type of rock, the API gravity of the oil, and the amount of gas in solution. As is to be expected, the ultimate recovery is found to increase with the oil gravity. except for the higher solution gas-oil ratios. Within the normal range of solubilities, the ultimate recovery generally appears to decrease with the amount of gas in solution for the higher oil gravities, and to show a slight increase for the lower oil gravities. Intermediate oil gravities seem to fall between the two trends. The type of reservoir rock, as identified by its relative permeability relationship, appears to have a very pronounced effect on the ultimate recovery. In general, sands and sandstones show higher recoveries than limestones and dolomites, although certain intergranular limestones seem to show a higher theoretical recovery than unconsolidated sand. The recovery from sands and sandstones generally decreases with increasing cementation and consolidation, while the recoveries from limestones and dolomites are highest for the intergranular type and lowest for the fracture type porosity.

Jan 1, 1956

By H. P. Greenwald, H. C. Howarth

The rapidly increasing use in coal mines of portable auxiliary fans, which are generally 'blowers" employed in connection with canvas tubing, raises questions concerning the hazards of such equipment, especially where the practices are opposed to established methods of ventilating face workings. Half a dozen or more coal-mine explosions and some fires have been attributed to the use of auxiliary fans; moreover, competent mining engineers have found many dangerous installations and methods of use-for example, intermittent running of the fans in gassy mines with consequent accumulations of firedamp at the faces. These facts have led the U. S. Bureau of Mines to issue this recommendation: "In the interest of safety, the Bureau of Mines, Department of Commerce, recommends that auxiliary fans or blowers should not be used in coal mines as a substitute for methods of regular and continuous coursing of the air to every face in the mine." The comparatively recent introduction of new types of mining machines, mechanical loaders, face conveyors, and slabbing machines has encouraged the trial of new systems of face mining, all of which have for their object the rapid advance of the faces. Although the latter has certain economic advantages, in gassy mines the rate at which gas is given off is generally found to increase in proportion to the speed of advance into new territory, which in turn increases the difficulties of efficient ventilation of the face workings. Some of the systems of advance mining being tried in connection with new mechanizing methods practically compel the use of blower fans and tubing, as single narrow places arc now driven 300 ft. or more without crosscuts. In some instances a series of parallel headings are driven without crosscuts pre-

Jan 1, 1928

By I. S. Servi, N. F. Graves

THE etch-pit technique has long been used to reveal low-angle boundaries and, in general, the distribution of dislocations in high-purity metals. Often this technique is amenable to quantitative computations,' but generally is affected by some degree of uncertainty because etch pits can be nucleated not only by dislocations, but also by inclusions and surface imperfections. In the case of high-purity zinc, Gilman' reported that etch pits were produced only after adding 0.1 atomic per cent of cadmium to the crystals and aging at a proper temperature. In the course of a study of low-angle boundary behavior in zinc crystals, etch pits were produced in 99.999 pct zinc without resorting to intentional contamination, by etching in a 50:50 HNO3H2O solution. The technique consists of etching until the heat of reaction brings the solution to a boil, and in displacing the etchant rapidly with a stream of cold water, thus avoiding staining. The undesirable features of this technique are the heating effect and the removal of a considerable amount of material. A high polish is obtained if staining is controlled properly; therefore, the etch pits appear very clearly and with excellent contrast when observed under dark field illumination. This is especially helpful for cursory examinations at low magnifications. Several observations were made on zinc crystals of square cross section, having one face parallel to the basal plane and one edge parallel to a slip direction, Fig. l(a). When such a crystal was bent about 2" over a glass die and annealed at 390°C, a sharp boundary was formed only in the inner portion of the crystal. Near the two prismatic faces, perpendicular to the basal plane, the boundary was always branched into many lower-angle boundaries, Fig. 1(b). Attempts to move the main boundary by applying a shear stress to the specimen invariably resulted in curving the boundary, the branched ends remaining pinned in their original location, Fig. 1 (c). The prismatic face, when etched as indicated in the foregoing, revealed the existence of numerous (sometimes up to 30) fine boundaries, nearly parallel to each other. Pre-existing lineage boundaries, generally parallel to the direction of growth, were barriers to the formation of polygonization boundaries and interrupted the continuity of the substructure, Fig. 2. Twin

Jan 1, 1959

By T. D. Yensen

In the investigation of the magnetic properties of iron-nickel alloys,' it was found necessary in order to make the alloys forgeable, or malleable, to add small quantities of some other element. Iron-nickel alloys have been known for nearly a century, but have been made in commercial quantities only since 1885. Their remarkable mechanical properties were disclosed by Riley in 1889 and from that time on a large amount, of research work has been done both to discover new properties and to correlate the results obtained.2 Lately the Bureau of Standards has collected the published data in a special circular" giving in compact form an account of the properties of the iron-nickel alloys. It also contains a clear historical sketch of the development as well as a selected bibliography. The chief difficulty with the development of iron-nickel alloys was that the "pure" alloys do not forge readily. The addition of small amounts of manganese, however, made the alloys forgeable, and manganese has therefore come to be regarded as a necessary constituent of nickel steels. The present paper shows to what extent manganese is needed for various nickel contents and also what is the effect of other alloying elements on the forgeability. It also touches upon the cause of forgeability but refers to other sources for more exhaustive treatises on the subject. The alloys were prepared by melting electrolytic iron and electrolytic nickel with or without other alloying elements in the desired proportions in a magnesia crucible in a vacuum furnace under a pressure of 1 mm. mercury. The ingots, weighing about 2 kg., were allowed to cool in vacuo. If pipes or blowholes were present, the ingots were cut in such

Jan 1, 1922

By T. D. Yensen

In the investigation of the magnetic properties of iron-nickel alloys,' it was found necessary in order to make the alloys forgeable, or malleable, to add small quantities of some other element. Iron-nickel alloys have been known for nearly a century, but have been made in commercial quantities only since 1885. Their remarkable mechanical properties were disclosed by Riley in 1889 and from that time on a large amount, of research work has been done both to discover new properties and to correlate the results obtained.2 Lately the Bureau of Standards has collected the published data in a special circular" giving in compact form an account of the properties of the iron-nickel alloys. It also contains a clear historical sketch of the development as well as a selected bibliography. The chief difficulty with the development of iron-nickel alloys was that the "pure" alloys do not forge readily. The addition of small amounts of manganese, however, made the alloys forgeable, and manganese has therefore come to be regarded as a necessary constituent of nickel steels. The present paper shows to what extent manganese is needed for various nickel contents and also what is the effect of other alloying elements on the forgeability. It also touches upon the cause of forgeability but refers to other sources for more exhaustive treatises on the subject. The alloys were prepared by melting electrolytic iron and electrolytic nickel with or without other alloying elements in the desired proportions in a magnesia crucible in a vacuum furnace under a pressure of 1 mm. mercury. The ingots, weighing about 2 kg., were allowed to cool in vacuo. If pipes or blowholes were present, the ingots were cut in such

Jan 1, 1922

A. SILVERMAN,* Pittsburgh, Pa.-Prof. Richards has described a very interesting process. In addition to the method described, electroplating and a number of other processes have been used. In one, the two metals were heated and united under hydraulic pressure; in a second, the steel was coated with an alloy, brass for example, and the molten copper cast around this. The process that I would like to bring to the attention of the metallurgists present consists simply of pouring molten copper, brass, or cupronickel around a clean red-hot steel billet. 'It is covered by the Roth patents. The 8-in. cylindrical billet containing about 70 per cent. steel (core) and 30 per cent. copper is hot drawn or rolled until several inches in diameter and afterward cold drawn or rolled to rod, wire of any desired diameter, or sheet. The wire is used for electrical conduits where conductivity and high tensile strength are required, also for the manufacture of cables and screen cloth. The sheet is employed for the manufacture of spouting, molding, shells, etc. The last application is particularly interesting. In testing rifle cartridges, which usually contain lead-filled copper noses, pine boards 1 in. thick, covered with ¼ -in. rawhide, are placed 1 ft. apart. The value of the cartridge depends on the number of boards penetrated by .the bullet. In government tests made with copper-coated steel noses (15 per cent. copper on either side of the steel) the penetrating power was found to be approximately double that of pure copper noses. The advantage of copper-coated steel over cupronickel lies in the fact that the- former does not require any special heat treatment during the punching. Rifle cartridges were prepared from copper-coated steel in a number of government arsenals. The value of the combination was attested by the awarding of a contract for the construction of a $3,300,000 plant. Unfortunately, the contract was signed on the day preceding the signing of. the armistice and was cancelled several days later. Tests were conducted for about 1 yr. before the contract was awarded to determine the value of this combination of metals. Since the war a number of cartridge and shell manufacturers have signified their intention of using copper-coated steel.

Jan 4, 1919

By Warren L. Howes

LITERALLY hundreds of designs of mill liners are in use in current grinding operations, varying in contour from smooth to the roughest of surfaces, and in materials from scrap rail to alloy steels. A certain amount of variation in materials can be expected, owing to differences in local market conditions and the character of ores. However, when one attempts to rationalize the designs in current operations of a parallel nature, there is little that can be called standard practice. Designs and opinions of designs are as divergent as day and night. Somewhere in this maze there must be clues to better practice. The purpose of this paper is to examine the factors for consideration in liner design, and to propose a vigorous campaign of exploration in this phase of grinding operations. The paramount considerations in the choice of mill liners for a grinding operation are: (I) durability, in view of the cost, and (2) developed grinding capacity. Because of the strategic nature of grinding circuits in controlling the production of most mining operations,1 grinding capacity usually is the greater consideration. GRINDING CAPACITY Mill liners affect grinding capacity in two ways: (I) by establishing dead space within a mill shell, which could be usefully occupied by live grinding media, and (2) by controlling the grinding action of the media. The extent to which liner thickness affects the potential volume of live grinding media, and thereby the grinding capacity, is shown in Table I. In a ball mill 7 ft. in diameter, for example, an inch of liner thickness reduces ball volume and corresponding grinding capacity by 5 per cent. With grinding capacity at a premium, this makes consideration something more than first cost of liner materials. A low-cost, voluminous material, made extra thick to secure adequate life, can be very expensive in terms of grinding capacity. On the other hand, in increased grinding capacity, a long-wearing material in a thinner pattern can save many times its value. [ ] From the standpoint of mechanics, the function of mill liners is to provide the means of driving or tumbling the load of grinding media. In this respect, an internal-spur gear-and-pinion assembly resembles a rotating mill shell with its contained load of grinding media, the mill-shell liners

Jan 1, 1945

By T. L. Joseph

THE committee appointed to investigate the application of oxygenated air to the blast' furnace believes, after a careful study of the problem, that this enriched air will increase hearth temperature, tonnage, flexibility of operation, and quality of pig iron made, and that fuel consumption will be decreased. These improvements are supported by theoretical evidence; but a practical trial of the process is necessary to establish more definitely the magnitude of benefits realized. The commercial application, however, may profitably be preceded by a test on a smaller scale. A small furnace will, in general, respond to the enriched air in the same way as a commercial furnace and the magnitude of the benefits to be gained from varying additions of oxygen can be fairly well established at relatively little expense. A new experimental furnace, being built jointly by the Bureau of Mines and the University of Minnesota, at Minneapolis, will have a capacity of about 6 tons and will riot require more than 700 cu. ft. of natural air per minute. Its hearth is 36 in. in diameter and its height about 32 ft. Enough oxygen to enrich the blast to the extent recommended by the committee can be obtained from a small oxygen unit. It might even be cheaper to perform preliminary experiments with tanks of oxygen obtained from regular, dealers. A procedure in making the test that suggests itself is to start with operation on normal air; then to use blast, enriched in several steps. Systematic temperature measurements of the tuyeres, slag, and metal would reveal any changes in hearth temperature. When these changes become large enough, the burden may be gradually increased to just within the breaking point and the furnace brought back to normal, if possible, by the addition of oxygen. Such a test would show what might be expected in the way of a decrease in fuel consumption and the time taken to "straighten up" the furnace by means of oxygen. The new furnace at Minneapolis is so equipped that the furnace process can be observed from the stock line to the iron notch. We have been taking gas samples at various elevations in the furnace to study combustibility of the fuel and the reducing power of the gas. If either of these is affected by removing inert nitrogen, the change can easily be measured.

Jan 11, 1924

The year 1934 saw a very thorough and intensive search for oil in Italy, both by the Government-subsidized company, the A.G.I.P., and by the few smaller operating companies. Approximately two-thirds of the exploration work, however, has been done in the Province of Emilia (northern Italy). The A.G.I.P. has been particularly active in the Emilia district and has sunk several rotary holes between Voghera and Ferrara on structures located by geophysical means in the Po Valley. Only insignificant amounts of oil have shown up in these tests to date but gas has been found in fair quantities, and apparently the company is not yet prepared to abandon its search in this part of the country without further effort. In Central Italy, the same company has put down four tests with cable tools and of these two were "dry holes" and the other two found only traces of oil. The A:G.I.P. also sank two wells in southern Italy and it is believed that in these the indications were sufficiently encouraging for the exploration work to be continued. No serious drilling has yet been done in Sicily by the A.G.I.P. or any other company. The annual subsidy granted to the A.G.I.P. by the Government for the duration of its five-year plan has been considerably reduced for 1935 and this may interfere with the completion of the coming year's program in all its details. The Società Petrolifera Italians, which is the chief producing company in the country, has continued the development of its two fields, Salsomaggiore and Vallezza, and at the same time has intensified its program of exploration. Rotary machinery has been introduced and is undergoing a thorough trial, and prospects of finding new pools at greater depths are considered good. The charcoal adsorption plant at Vallezza has operated satisfactorily throughout the year and has produced nearly 3000 bbl. of high-grade gasoline. Besides the exploration well at Rile dell'Olio, which is still drilling, another wildcat test has been started at Torre-di-Traversetolo. All operations of this company are confined to the district of Emilia. The Società Petroli d'Italia has continued to operate the old fields of Montechino, Gratera and Velleja, and has a well now exploring at greater depths in that general area. Of the two exploration wells in the Torino

Jan 1, 1935

By Robert M. Betts

The Cornucopia district is situated in northeastern Oregon 25 miles from the Snake River branch of the Oregon Short Line R.R. and 75 miles northeast of Baker City, in the Wallowa Mountains. The formation is principally granodiorite, which has intruded much older rocks locally known as greenstone, and which are probably altered schists. In the upper horizons of the veins, greenstone is found as inclusions in the granitic mass. Both of these formations have been cut by numerous basalt, aplite, and porphyry dikes. Veins of the district are the result of faulting and the consequent crushing of the wall rock. The ore has been deposited irregularly along these faults and formed a lenticular type of vein. The ore varies in width from a few inches to 20 ft.; the average stoping width is about 5 ft. As the basaltic dikes are subsequent to the ore deposition, they are at times a hindrance in development and mining operations; on the other hand, a dike which has followed a vein as a line of least resistance often serves as a good mall in place of the crushed, rather loose granite. The veins generally strike northeast-southwest and dip about 35" to the west. Orebodies are from 100 to 300 ft. in length and about the same in height. The lenses are irregular; inclusions of wall rock are common in the ore and are a factor in reducing the grade. The ores are quartz, carrying some free gold near the surface, but the metals for the most part are in iron sulfides, sometimes associated with chalcopyrite. The gold and silver are in a mechanical combination with the iron, which requires find grinding to liberate them. The ratio of silver to gold is 5 to 1, by weight. Development The Cornucopia Mines Co. owns, and operated until 1920, two mines and two mills of 100 tons capacity each. The sustained high costs and labor shortage, however, necessitated the abandoning of the Union mine, the oldest in the district. Two crosscut tunnels were then started, first, to cut the Last Chance vein at a much lower horizon and, second, to prospect two parallel veins. The ore from the Last Chance vein will go to the old Union mill and the ore from the new veins to the Last Chance mill.

Jan 1, 1925