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By Ellsworth Daggett

Jan 1, 1879

Frank Firmstone, Easton, Pa. (communication to the Secretary*) : It may not be amiss to point out that the top-pressure in iron blast-furnaces is largely affected by variations in the temperature of the gas. I find in my note-books, cases in which the pressure was from 9.25 to 9.5 in. of water when the material in the furnace was low (after dinner-hour), which fell to from 8 to 8.5 in., when the furnace was again full, and the gas consequently cooled. The chief cause for this effect is, that, at the higher temperature, there is a decrease in the weight of the gas in the descending-leg of the siphon formed by the down-comer and the chimneys. It does not seem probable that there is any direct relation between top-pressure and quantity of flue-dirt. Top-pressure, at any given moment, measures the " head " necessary to discharge the gas then passing, against the resistances of pipes, valves, etc., in the gas-conduits between the top of the furnace and the mouths of the chimneys, and can be increased at will by closing, more or less, the valves, or dampers, at the stoves and the boilers. The question of relation between top-pressure and flue-dirt can be settled very easily by direct experiment, working alternately with gas-valves open, and partly closed, and noting the top-pressures and the respective quantities of fluedirt collected. The quantities of fine ore blown away, as shown by Mr. Grammer's tables, are astonishing to one who has had no actual experience with Mesabi ore and hard driving. Flue-dirt, in the sense in which he uses the term, was unknown at anthracite furnaces so long as the working was normal; when it did occur, it was always an incident of scaffolding and bad work, and was no doubt caused by an increase in the velocity

Jan 1, 1904

By R. M. Brick

EDUCATIONAL benefits for veterans of World War II have largely removed one of the two former barriers to a college education for everyone, namely financial means and intellectual capacity. This latter limita¬tion has not kept privately endowed institutions from increasing 50 to 100 percent in size of student body, even after applying moderately rigid entrance standards. Growth of some land-grant universities, which cannot well exercise such restrictive judgements, has been even greater. After a weary board of admissions, subject to student, alumni, faculty, and even political pressures, has admitted double the former number of freshmen, the university's worries really begin: to find laboratory, classroom, and instructional facilities. If this were a one- or two-year problem, the answer would be simple: double up, hold night classes, particularly of laboratories, rent space, and have instructors work 24 class or contact hours a week instead of twelve (it takes usually two to three hours of outside work by the instructor for one hour in class). However, most engineering school faculty men are worn out now from four to five years of "accelerated" (frequently downward!) programs and they couldn't continue teaching in a way satisfactory to their own consciences on

Jan 1, 1947

By R. T. Mishler

I wish to express my keen appreciation of the article on the above subject by Coe and C1evenger.l It has been doubly interesting to me, for the reason that the experience recorded and the principles evolved practically parallel the results of similar investigations made by myself and others at The Lucky Tiger Mine, El Tigre, Sonora, Mex. An outline of the work at El Tigre may aid in confirming the principles expressed by Coe and Clevenger. El Tigre has the unenviable distinction of possessing a slime with a much lower settling rate than any recorded in the article discussed. Under most favorable conditions the settling rate is about one-third that reported for the Liberty Bell mill, and one-tenth that reported for the Nipissing, Golden Cycle, and Presidio mills. This slow settling characteristic of Tigre ore has necessitated careful investigation of settling phenomena throughout the various evolutions of the plant. Previous Settling Investigation at Tigre During construction work at the mill, the metallurgical engineer in charge, D. L. H. Forbes, ran a series of experiments on settling. His tests proved that deep settling tanks were not ordinarily necessary. The use of tanks 2 or 3 ft. in depth was suggested.2 Later experiments demonstrated that the following principles of settling applied to Tigre pulp.3 1. In settling dilute pulp, settling rates are independent of pulp depth. 2. In settling thick pulp, settling rates are approximately proportional to pulp depth.4

Jan 1, 1918

Jan 1, 1892

Aamot, Olav Crone, Research Engr., Norsk Elektrokemisk Kongensgt, 18, Oslo, Norway ?29 Abbott, Clarence E., V.P., Charge of Raw Materials, Tenn. Coal, Iron & R. R. Co., 1242 Brown-Marx Bldg., Birmingham, Ala. '04 Abbott, Louis Benjamin, Chief Engr., Consolidation Coal Co., Watson Bldg., Fairmont, W. Va. '15 Abel, Raymond L., Asst. Prof., Dept. of Pet. Refin., Univ. of Pittsburgh Pittsburgh, Pa. '28 Abel, Walter D., Cons. Engr 364 S. Cloverdale Ave., Los Angeles, Calif. '32 Abele, Louis T 1457 Euclid Ave., Zanesville, Ohio. '31 Abell, Leo M Sullivan Concentrator, Chapman Camp, B. C., Canada. '31 Aborn, Robert H., Asst. Met., Research Lab., U. S. Steel Corp., Lincoln Highway, Kearny, N. J. '19 Abraham, W. E. V., East India United Service Club, 16 St. James' Sq., London, S. W. 1, England. '28

Jan 1, 1936

By George C. Stone

AS most of you probably know, Australia has had many strikes. The two places that had the worst reputation were the Broken Hill mines and Port Pirie, where the smelter was located. About four or five years ago, the smelter changed hands. The new proprietors - immediately endeavored to get on better terms with the men and made such progress in that respect that, the men came to them and said, "There is no use giving us any more money. You have just raised our pay one- bob a day, but the store-keeper and the boarding-house keeper have raised their prices. The boarding housekeeper raised our board three bob a week and the storekeeper took the rest of it and we are no better off." Learning that what the men needed most was firewood wood the company bought the wood on a tract of ground across Spencer's Gulf and- sent men over to cut it. The wood was brought to the works and given to a man to cut up. He thought he had an easy job and loafed, but when the committee representing the men discovered that his loafing added to the cost of 'the wood, it promptly disciplined him and made -him work as he had never worked before. The next question that arose was the distribution of the wood. The committee got bids from several cartmen whose prices varied from about two to five shillings. It gave the work to the next to the lowest bidder. The fact that if delivering the wood cost more, the user would have to pay for it, was an entirely new idea to the men.

Jan 1, 1920

[59H1-Water Law and Its Significance to the Mining Industry by Wells A Hutchins 59H2-Relation of Land Subsidence to Groundwater Withdrawals in the Upper Gulf Coast Region, Texas by Leonard A Wood and A G Winslow 59F3-Hydraulic Mining of Gilsonite and Its Application to Coal Mining by J H Baker 59H4-Recovery of Phosphates by In Situ Fluid Mining by Sylvain J Pirson 59F5-Coal Cleaning Plant Design for Minimum Operating Labor by Wm M Bertholf and John D Price 59F6-Coke Combustibility A Neglected Characteristic by J D Price 59B7-Union Carbide's Uranium Operation at Maybell, Colorado by K W Lentz and F T Temple 59H8-A Rapid Method for Estimating Alumina in Feldspathic Sands by Hugh H Bein 59H9-Water Laws as Related to Dredging in Idaho by Robert A Lothrop, Richard B Porter, and Robert P Porter 58B19-Separation and Washing of Alumina Process Residue by Morton Handelman 59B11-Feed Preparation and Froth Modification for Fatty Acid Flotation by Carl C Martin and Burt C Mariacher 59B12-Design Requirements for Tailing Disposal in the Southwest by E Vern Given 59B13-Semi-Dome Shaped Buildings for Bulk Storage by Edward E Ives and William L Payne]

Jan 1, 1961

By Anwar-ul Karim

In one of our recent papers, Cheng, Karim, Langdon, and Dom1 analyzed the creep mechanisms in a Fe-4 pct Si alloy. The experimental results of apparent ac-

Jan 1, 1970

By Lucien Eaton

INCREASED mining activity during the past year has brought to light changes in mining practice and advances in technique, born and incubated in the period of depression from which the mining industry is now emerging. Although the tendency toward large output from individual mines has continued, a salutary trend is evident toward greater efficiency at small mines, in which the gold mines of Canada have led the way. Improvement in excavating machinery and washing plants for small placers has continued, and knowledge of the possibilities and limitations of this kind of equipment has increased. Greater portability through sectionalization has been the keynote. Power, shovels and draglines mounted on caterpillar treads move from one deposit to another under their own power, and floating washing plants mounted on pontoons can be taken down, moved, and set up again by a small crew of men in only a few days.

Jan 1, 1937

By William R. Webster

This is a subject which our Institute has made peculiarly its own. In the first volume of its Transactions the analysis of steel received attention, and every subsequent volume has borne witness to the acuteness and industry of our members in the investigation of this subject. The keynote mas struck, in this as in so many other lines of progress, by A. L. Holley, in his paper on " Tests of Steel," read at the Easton meeting of October, 1873 (Trans., ii., 116)—an essay which may rank as a classic by reason of .its elegant form, logical force, and clear prevision of all the bearings of its theme, Taken together with the brief report of the discussion which followed it (in which Dr. Drown emphasized the effects of heat-treatment and mechanical handling, and Dr. Sterry Hunt the importance of minute variations in chemical composition, and of possible isomeric and allotropic conditions), it constitutes, after the lapse of twenty-five years, an admirable and adequate introduction to the long list of technical papers which have succeeded it. Three years later came the epoch-making papers of Dr. C. B. Dudley on the relation between the chemical composition and physical properties of steel rails, which, with the voluminous discussion they evoked, constitute a special volume, published by the Institute, and full of useful suggestions. If Dr. Dudley could be induced to resume this investigation, he would doubtless be able to solve many points still uncertain or disputed. But I cannot undertake to review the history of this subject, as represented in our Transactions—still less to restate all the contributions to it which have been made in books or in papers before other technical societies, since the initiative was taken by the Institute. My more modest purpose is to indi-

Jan 1, 1899

By R. Gibala

Internal-friction measurements on hydrogen-charged iron over the temperature range 4° to 300°K are reported. Two relaxation peaks, the hydrogen Snoek peak at 48 °K and the hydrogen cold-work peak in the range 145" to 2200K, are observed at 80 kc per sec. The effects of hydrogen-charging, aging, and deformation on the internal-friction results are determined and are used to show evidence of partitioning of hydrogen between solid solution and dislocations. The hydrogen-dislocation binding energy is estimated from the behaviors of the relaxation tiwzes and relaxation strengths of the Snoek peak and the cold-work peak. Its value is approxi,mately 6400 cal per mole. MANY investigators have demonstrated the usefulness of internal-friction measurements in determining the manner in which interstitial impurities interact with dislocations in bcc metals. Part of this success has resulted from the existence in bcc interstitial alloys of two anelastic relaxation peaks—the Snoek peak' and the cold-work or Koster peak2 (designated hereafter by SP and CWP, respectively). The SP has its origin in the redistribution of interstitials in solid solution among sites made energetically nonequivalent by an applied stress. The rate at which the redistribution occurs, measured by the relaxation time for the process, is related in a simple way to the diffusion rate of the interstitial in the free solution. The relaxation strength is proportional to the concentration of interstitial in solid solution. The CWP appears to have its origin in the relaxation of an interstitial-dislocation complex for which the relaxation time at a given temperature is much longer than that for the SP. The relaxation strength depends strongly on the concentration of interstitial and the amount of deformation at relatively low concentrations and deformations.2-8 From the dependence of the relaxation strength on interstitial concentration, the SP and CWP may serve as measures of the concentrations of interstitials in free solution and bound at dislocations, respectively. Thus their behaviors have been used to investigate interstitial-dislocation interactions in Fe-C, Fe-N, and several refractory metal systems.'-' However, the Fe-H system has not been studied extensively,? even though disputes in recent years over the mechanism of hydrogen embrittlement in steels involve argument over the extent to which lattice hydrogen and hydrogen-dislocation interactions play an important role.?-'' Previous work on Fe-H indicates the internal-friction behavior to be qualitatively consistent with that for other systems. Apparently, both a SP and a CWP are observed in the temperature ranges 30" to 50°K and 100°to 140°K, respectively (at 1 cps). However, there is neither sufficient nor accurate enough information to identify convincingly these peaks with their supposed counterparts in other systems. Nor have there been any attempts to make quantitative use of these peaks to study hydrogen diffusion, aging, or interaction processes. In this paper, an attempt is made to obtain more complete information on internal friction of hydrogen in iron than presently available. Internal-friction measurements in the range 4° to 300°K on hydrogen-charged iron show that the two peaks discussed above are in fact the hydrogen SP and CWP. Several effects of hydrogen charging, aging, and deformation on these peaks are observed and are used to determine the partitioning of hydrogen between solid solution and dislocation sites in iron. EXPERIMENTAL Materials. The starting material for this investigation was a high-purity iron supplied by National Research Corp. as a 1-in.-diam rod. The following analysis was given (inwt pct): C, 0.004; N, 0.0003; 0, 0.007; P, 0.002; S, 0.005; Si, 0.006; Mn, 0.001; Cu, 0.002; Ni, 0.005; Cr, 0.001; Mo, 0.001. After an initial vacuum anneal (-5 XTorr) at 700°C, the rod was cold-

Jan 1, 1968

By Roger L. Beals, George A. Tweedy

The results of the cyanide-operations, given in detail in the following paper, show the progress that is being made at the Minas del Tajo. The old pan-amalgamation process, in operation up to and including 1905, while paying a profit on high-grade ores, was no longer able to treat profitably the ores in sight at that time; hence an alteration in the process was imperative. The success of this alteration is eloquently expressed by the following data : Pan-Amalgamation. Cyanidation. 1905. 1905. " 1908. Tons treated,.... 51,387 58,983 69,200 Value per ton (U. S. currency),. $ 10.78 $8.39 $8.28 Extraction, per cent.,.. 65.00 88.56 87.45 Extraction, per ton,.. $7.00 $7.43 $7.24 Total cost, per ton treated, . 6.50 4.36 4.01 Profit, per ton treated,.. 0.50 3.07 3.23

Jan 1, 1911

Jan 1, 1932

By B. W. Levinger

THE system Ti-CI- has been studied by several investigators." ' Though titanium and chromium are completely miscible at high temperatures, an intermediate phase of the approximate atomic proportions TiCr, has been identified at various compositions between 60 and 68 wt pct Cr. The structure of this phase was established as the cubic C15 (MgCu2) type with 24 atoms per unit cell and a lattice parameter 6.929 kX.2 During a study of the ternary system, Ti-Mo-Cr,5 the existence of a high temperature modification of the TiCr, phase was discovered. In a series of alloys annealed at 1300°C and containing from 60 to 70 wt pct Cr and 5 pct Mo, a new phase was present which did not correspond to either ß solid solution or TiCr,. By trial, the new phase was identified to be of the hexagonal C14 (MgZn2) structure with 12 atoms per unit cell. Further work showed that the hexagonal structure was. in fact, also present in binary Ti-Cr alloys quenched from high temperatures. To make the identification more certain, the intensities of the various reflections were calculated assuming a composition TiCr2 and C14 structure. Table I lists reflection planes, interplanar distances, calculated intensities, and a comparison of these values with the lines of a binary Ti-Cr alloy (66 pct Cr) annealed for 20 min at 1385°C and water quenched. Since high angle lines were more diffuse, the correspondence between visually observed and calculated intensities was not as good at these angles. Lattice parameters were computed to be a = 4.922 kX, c = 7.945, c/a :- 1.614. The corresponding interatomic distances are: titanium to titanium distance, 3.00:, kx, chromium to chromium distance, 2.43, kX, titanium to chromium distance, 2.88,, kX. These compare to 3.00, 2.45, and 2.87 kX in the cubic phase, respectively.' The atomic positions in the C14 structure are as follows: Titanium 1/3, 2/3, Z; 1/3, 2/3, 1/2: 2/3, 1/3, i; 2/3, 1/3, (1/2-z); Chromium 0, 0, 0: 0, 0, 1/2; 2x, 2, 1/4; 232, x, %; X, 22, 1/4; X, 2x, 3/4; x. x, 1/4; x, x, 3/4; The values of x and z were calculated for the alloy mentioned and found as follows: z — 0.061, x = 0.165. The values assumed in the intensity calculations were those for an ideal close-packed lattice or z = 1/16, x = 1/6. Work in the Ti-Mo-Cr system indicates that y2 the hexagonal modification of TiCr2, is the stable phase above 1300°C, while y1 with the cubic structure is stable below 1000°C. X-ray examination of a number of alloys annealed at intermediate temperatures showed that the hexagonal and cubic phases can coexist. Alloys quenched from 1000°C and annealed at 1100" and 1200°C showed small amounts of y2 at the higher temperature. A considerable amount of y, seemed present, however, in cast alloys annealed at 1100°C. It further appears that there is a small but definite solubility range for both phases in the ternary system. Acknowledgment The results of this paper represent work carried out in conjunction with a project sponsored by Watertown Arsenal, Contract No. DA-11-022-ORD-272. References 'M. K. McQuillan: Journal Inst. Metals (1951) 79, p. 379. 2 P. Duwez and J. L. Taylor: Trans. ASM (1952) 44, p. 495. W. J. Van Thyne,. H.. D. Kessler, and M. Hansen: Trans. ASM (1952) 44, p. 974. 1 F. B. Cuff, N. J. Grant, and C. F. Floe: Trans. AIME (1952) 194, p. 848; Journal of Metals (August 1952). Unpublished Research, Armour Research Foundation. "H. J. Wallbaum: Ztsch. Krist. 103, p. 391.

Jan 1, 1954

By S. H. Brockunier

During the examination of a gold-property in Georgia, last summer, I had occasion to study the effect of different chemicals upon the ore; the object being to find a more economical method of extraction than chlorination, as practiced there, had proved to be. Some of my notes and results may be of interest to others. The country-rock consists of mica-schist, hornblende-schist and black slate. The vein-matter is quartzite and schist, containing some stringers of quartz, the whole forming a body from 20 to 50 ft. wide. All of the rocks in the vicinity have become disintegrated to a depth of from 50 to 75 ft., forming the so-called saprolite. I found the workings to represent two distinct classes : I. Open-cut surface-ore: very soft,oxidized and disintegrated; containing much alumina, silica and iron. Average value, $4 per ton. 11. Ore from lower levels : quartzites and schist; very hard ; containing much silica and manganese, some alumina, and from 2 to 10 per cent. of pyrites. Average value, $8 per ton. Class I. was soon dismissed. The only way to make it pay would have been by the use of steam-shovels and a large crushing-plant. The tendency to slime would be the principal difficulty.

Jan 1, 1902

By P. S. Martin, B. J. Guarnera

As an energy source, lignite is short on selling points-it contains large amounts of moisture and often large amounts of ash, resulting in low heat content. The moisture produces rapid oxidation upon exposure and self-ignition commonly occurs within two to three weeks, resulting in major transportation and storage problems. Nevertheless, as interest in alternate fuel sources increases, lignite deposits in the Coastal Plain of the US are attracting more and more attention. Two lignite mines are operating in Texas and additional developments are planned in that state, Arkansas, and Louisiana. At present, Texas lignite is burned only at mine-mouth generating facilities, but more exotic uses such as gasification are projected in the future.

Jan 4, 1979

By C. A. Stetefeldt

Metallurgical processes cannot be conducted successfully With out the aid of analytical chemistry. The great perfection of Iead smelting in the West, for instance, has only been accomplished by the analysis of ores, fluxes, slags and all products of the furnace. Ores are mixed and fluxed to obtain a slag of desired composition. Account is even taken of the composition of the ashes obtained from the coke. The " muscular " smelter has left the field forever! This state of affairs has been induced by sharp competition, i.e., by a com plete separation of the industries of mining and reducing ores, not by the liberality and wisdom of directors and stockholders to pro vide laboratories and engage chemists, or by their love for scientific investigation. It would be considered absurd, at present, to run a lead-smelter, a blast-furnace for pig-iron, or a Bessemer plant without the assist ance of a well-equipped laboratory and a chemist; but it is con sidered quite sufficient to provide amalgamation- or lixiviation works merely with a crude assay-office, and an assayer who is paid less than a laborer in the mill. In my opinion, this will change in the near future. By the ex clusion of Mexican lead-ores, and their growiring scarcity in the West, smelters have been forced to raise their charges on so-called dry silver-ores, and cannot handle the latter now in such unlimited quantities as formerly. The inevitable result must be that the sur plus of these dry silver-ores, especially those of low grade, will be reduced by processes cheaper than smelbing; and here the introduc tion of lixiviation has an excellent field, provided the muscular lixiviator has an able chemist for an assistant. It is to be regretted that so little analytical work has been done in lixiviation. We know almost nothing of the composition of roasted ores before and after lixiviation; of the constitution of the first wash water and of lixiviation-solutions after prolonged use; of the chemistry of sodium and calcium sulphides; of the col-hposition

Jan 1, 1892

Crushed limestone is now being "de-dusted" at the Warner Co. plant in Bellefonte, Pa., by a new high-efficiency classifier utilizing aerodynamic principles not previously employed in classifiers. Crushed limestone for certain glass industry requirements must not have more than 10 pct fines in the overall aggregate, and it is the function of the new-type classifier to separate these fines from the coarse material. During the development of this classifier by the Buell Engineering Co. of New York, it was found to have possible applications for separating pulverized coal, sintered metals, ores, mineral flours, and fillers, among other items. Limestone from Warner's deep mine is initially crushed and particles larger than 3/8-in. mesh are burned in kilns to provide calcium oxide for the chemical industry. The 3/8-in. screenings are dried and crushed to -16 mesh for use by the glass industry. For those applications requiring a minimum of fines, no more than 10 pct -100 mesh material is allowable in the end product. Hence the need for high-efficiency separation.

Jan 11, 1960

By C. E. McCarthy, A. George Stern, Stanley J. Green

THE national interest prompts consideration of any new source of mineral wealth even though the immediate need may be of minor importance. A critical shortage of potash in the United States during the World War of I9I4-I8 stimulated broad development, which established an American potash industry on a basis so sound that this commodity is not even listed as urgent in the present war program. However, this should not minimize its importance, and the need remains, not only for adequate supplies of the usual potash salts (the chloride and the sulphate) but of all potash chemicals. Potassium carbonate (known commercially as pearl ash) has been a high-cost commodity; in consequence, the quantity used by industry has been relatively small. By a combination of fortuitous geographical circumstances, there is opportunity to produce a low-cost potassium carbonate with the possibility that this might become an important source of chemical potash. The following paper considers a recently developed process1 taking advantage of these conditions. WYOMINGITE DEPOSIT For many years it has been known that a deposit of potash-bearing igneous rock known as wyomingite occurs in the southwestern part of Wyoming at Zirkel Mesa, which is 44 miles northeast of the town of Green River (Fig. I). The western escarpment of this deposit is about 3 miles east of the Superior Branch of the Union Pacific Railroad. This mesa alone covers approximately 3300 acres, and the average thickness of the wyomingite flow is 75 ft. It has been estimated2 that about one billion tons of wyomingite occur in this one deposit, all of which can be mined by open quarrying without overburden. In addition, there are several smaller deposits within 10 miles, so that the aggregate wyomingite in the area approaches two billion tons. This is one of the world's largest sources of leucite, and the only known deposit of its kind in the United States. The wyomingite (which is in the form of a lava flow and numerous small craters), with the mineral leucite as its most important component, has a mineral composition3 of: leucite, 50 per cent; phlogopite, 15; diopside, I2; kataphorite, 15; glass and apatite, 8. The phlogopite is present in visible phenocrysts 1/8 to 1/2 in. in diameter, but the leucite usually is almost microcrystalline and not capable of liberation by grinding. Chemically, the wyomingite has a potash content averaging slightly higher than eleven per cent K20. The potash is mainly in the leucite, but part of it is in the phlogopite and a small amount is in the feldspars that are occasionally seen as undigested occlusions of the granite country rock, through which the leucite-bearing lava intruded, and as sanidine feldspar both in the crystalline and glassy phases of the rock. A typical analysis of the wyomingite from Zirkel Mesa is as follows:

Jan 1, 1944