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By W. R. Ingalls

Jan 1, 1922

By W. R. Ingalls

Jan 1, 1922

By William H. Hallahan

The Friedensville zinc mine of The New Jersey Zinc Company is located about four miles south of Bethlehem, Pennsylvania in the Saucon Valley, an infolded and down faulted block of Cambro-Ordovician carbonate sediments surrounded by hills of pre-Cambrian gneiss and Cambrian quartzite except where breached by Saucon Creek at its entrance into the Lehigh River. The Beekmantown formation of lower Ordovician age is the host for zinc and limonite ores, the former occurring in the lower dolomitic portion thereof and the latter in the upper interbedded dolomite and limestone portion of the section. The Beekmantown is overlain unconformably by the Jacksonburg of middle Ordovician age and according to Miller (2) underlain conformably by about 2500 feet of Cambrian dolomites and 200 feet of the basal Cambrian Hardyston quartzite. Igneous rocks, younger than the Cambro-Ordovician carbonate rocks, are absent in the vicinity of the ore deposits. The major structure is a N60°E-trending saddle-shaped doubly plunging anticline overturned to the north. A syncline lies to the north of the anticline. A thrust fault of substantial displacement repeats the south limb of the anticline. The ore consists of sphalerite and pyrite, along with gangue dolomite and quartz, filling and replacing the sedimentary type matrix of a strata-bound solution collapse breccia in the dolomitic portion of the lower Beekmantown. This breccia was produced in pre-Jacksonburg time as a consequence of uplift, erosion, and development of a karst topography and subsurface drainage system in the Beekmantown. Deposits of both zinc and limonite are present on the vertical north limb, on the crest and on the gently dipping (25°) south limb of the Friedensville anticline; consequently, there is no preferred structural setting for mineralization. Rather this distribution supports the view that the folding is post-ore. Features confirming this view are the development of flow cleavage in the breccia matrix, the deformation of some of the sphalerite, and the fracturing of the pyrite mineralization therein. There is nothing to indicate that the age of mineralization is other than Ordovician and older than Taconic deformation. In the absence of intrusive igneous activity younger than the ore host, the writer suggests that submarine volcanic exhalations associated with the volcanic activity recorded in the eastern eugeosynclinal facies of the Ordovician may be the source of the metal ions.

Jan 1, 1968

By John Howe Hall

One's first thought, upon being chosen to deliver the Henry Mario Howe lecture, is of pride at being selected for this post of honor, but ther succeeds immediately a deep sense of the Obligation thereby incurre to give of one's very best in order to make a contribution worthy of hir in whose memory these lectures are given. One who had the goo fortune to be associated with Henry ill. Howe, upon sitting down t prepare such a paper as this, irnrnediately falls to musing upon thc day when his face and his footfall were familiar from constant association, an recalls with singular vividness his active figure, his mobile, alert face, an his keenness in penetrating to thc corc of the subject under discussior Like Dr. Mathews, I was a young man when I first worked under hi direction, now nearly a quarter of a century ago, and in those early day he oft,en seemed a hard taskmaster—a man whose standards it woul never be possible for me to meet. I well recall his insisting upon m proving for the third time the truth of a conclusion which I had brc unwilling to submit to him until it had been confirmed by two carefull planned experiments. To my impatient protest that thc third .demor stration he asked for was but a repetition of the second, with differer samples, he replied, "Yes, that is true, but the inherent improbability ( your conclusions is so evident that I can not accept them until you prov your case again." "Shall I ever do a thing well enough to suit him? I thought. Looking back today upon many similar incidents, 1 suspect that h never expected me to attain the excellence he preached, and held up t me and to himself as a model, but knew out of the fullness of his experienc. that in no other way could he so impress upon me the necessity in researc of the patient, never-failing attention to detail and to accuracy tha distinguished his own work. How painstaking he was in the preparation of his many books an professional papers, as well as in his experimcntal work, was ncvcr s

Jan 1, 1929

By George W. Friesen

This paper presents the historical trend and de- fines the causes of drilling cost escalation in the Gulf of Mexico during the 1970's. The three major components of escalation are: 1) inflation, 2) supply-demand imbalance (demand pull) and 3) decreases in drilling efficiency. The decade was divided into three periods. During each period one component of escalation was responsible for most of the rise in costs. From 1970 through 1973 only inflation pushed costs upward. During 1974 and 1975 a supply- demand imbalance caused most of the escalation. Since 1975, decreases in drilling efficiency have produced the major component of escalation. During any one year or period of years, the sum of the three components will give the total escalation rate. The reasons why different components contribute more toward escalation during certain years than others are shown by following the timing of oil and gas price increases, the overall quality of the acreage offered each year in offshore lease sales and the resulting drilling activity.

Jan 1, 1982

By H. Van F. Furman

As the cyanide-method for the extraction of gold from ores is extensively used in the United States and elsewhere, and appears destined to prove a factor of increasing importance in the metallurgy of gold, a description of the latest laboratorymethods may prove of interest. The history of the development of the process in the United States has been analogous to that of all new processes. Many failures are to be recorded and a few successes. It is the opinion of the writer that, had the following simple tests been better understood, many of the failures would not have occurred, and we should probably have a larger number of successful plants in operation. While the process is not simple, but requires a high degree of chemical and engineering skill, the determination of the adaptability of an ore to the method is generally not difficult. While the laboratory-results will not always coincide with the actual results obtained in the mill, they will serve as a guide and control on the working of the mill, and mill generally suffice to determine if the ore can be

Jan 1, 1897

By W. S. Row

This mine is operated at 4000 to 4500 tons daily through a single shaft, with one rock hoist and one senice hoist. Latest shaft construction is concrete with wooden dividers. Economics of drifters and air-leg drills are compared, as well as costs of shrinkage and sub-level stoping. Economy of large haulage equipment and underground crushing is shown. THE property of Kerr-Addison Gold Mines is located in the Larder Lake district of Ontario about 3 miles from the Quebec boundary on the highway between Kirkland Lake and Noranda. It is roughly 320 miles due north of Toronto and 365 miles north of Buffalo, N. Y. The property was staked in 1906 and after several development efforts finally came into continuous production at 500 tons per day in 1937. In 1939 the daily tonnage -was increased to 1200 and in 1941 to 2100 tons. At the end of the war, because of the shortage of labor, tonnage was down to 1100 tons per day, rising to 2200 in February 1947. A further plant expansion inaugurated in 1946 was completed by December 1948, bringing the capacity of the mine and mill to a production rate of 4000 tons per day. Current production, with 880 men employed, is 4400 tons per day. Changes in mining methods and equipment, required by the recently completed expansion program, have yielded interesting comparative results, some of which are described in this paper. Hoisting of ore and waste from the mine, as well as all service facilities for handling men and supplies underground, are provided for in a single vertical five-compartment shaft. Ore and waste are hoisted in 12½-ton skips in balance by a 14-ft diam hoist with drums 115 in. wide, grooved for 2?-in. wire ropes. This hoist, with a total rope pull of 85,000 lb, was designed to operate at a speed of 2600 ft per min to a depth of 4000 ft, hoisting 15 tons of ore in each skip. It is amplidyne-controlled and powered with dual drive dc motors of 2250-hp each, through flexible couplings to two pinion shafts, one on each side of the main gear. Each motor has a peak load rating of 4500-hp at point of greatest duty. Direct current power to the hoist motors is supplied from a motor generator set consisting of a 5000-hp synchronous motor driving two 1750-kw dc generators. The loading pockets used so far are at depths of 1500 and 2725 ft respectively. Consequently the present hoisting speed is 2000 ft per min and the skips capacity only 12½ tons. Now that the shaft has been deepened the new pockets at 3934 ft will be increasingly used so that the speed and the skip size will be increased up to original specifications as required. Some difficulty in meeting the required hoisting cycle is expected because of the shape of the skips. As now in use the cross-sectional dimensions of the inside of the skip are 4 ft 6 in. x 3 ft 8 in. To hold 121/2 tons, therefore, they are 14 ft 10 in. deep. Since the skips are the conventional overturning or Kim-berley type, considerable hoisting time is lost in retardation in entering the headframe dump and in acceleration when leaving. It is expected that to obtain the specified tonnage from this hoist when the skip size is increased to 15 tons it may be necessary to resort to bottom dump skips. This type of skip could reduce considerably the present excessive acceleration and retardation times. Analyses of the skip-hoisting operation are made monthly, and every effort is made to reduce controllable delays. For a nine-month period in 1951 such an analysis shows that the hoist was in operation 92.5 pct of the available time, which was allotted as shown in Table I. Overall hoisting costs, cage and skip, for the year 1951, averaged $0.168 per ton of ore milled. The mine is serviced entirely by means of a single cage, capacity 35 men or 15,700 lb, operating in con-

Jan 1, 1954

By Walter Miller

With returning prosperous conditions in all industries, oil-refinery engineering has found opportunity for the more extensive application of improvements developed during the several years of depression. The year has brought out little of an entirely new nature, but much in wider application of previous worth-while developments. The greatest volume of work done has been in modernizing the distillation and cracking units of existing refineries, particularly by substitution of combination skimming and cracking units for older equipment, and the installation of cracking plants in smaller refineries where formerly only skimming was practiced. A number of entirely new refineries were installed during the year, two of the most important being the 20,000-bbl. refinery by the Atlantic Refining Co., at Atreco, Tex., and a 12,000-bbl. plant by the Wilshire Oil Co., at Norwalk, Calif., these two embodying some of the latest developments in cracking and treating. Total refining capacity for the United States is now reported as being something over 4,000,000 bbl. per day, but a movement is on foot looking to a complete revision of these figures, as experience has indicated not only some overstatement of capacity of equipment but that considerable equipment is included which because of obsolescence and location will probably never be run again. The 3,000,000-bbl. figure which the industry reached during the year's high consuming period required the operation of probably 95 per cent of the country's efficiently usable capacity. Cracking and Polymerization There were no new outstanding developments in the cracking field, progress being made largely in the further refinement of known principles. Improvements in furnace design and operation have been largely in permitting closer control of the heating curve through the cracking-tube system, assisting in more uniform yield and in the lessening of coke deposition, and permitting longer trouble-free operating time as well as reduction in furnace-maintenance cost. Actual operating polymerization capacity has been increased little during the year, but a number of projects have been started, some nearing completion, the production from which will be available during 1937.

Jan 1, 1937

By Stefan Boshkov, Malcolm T. Wane

The validity and accuracy of velocity measurements underground have been questioned repeatedly by those in mine ventilation work. The general disagreement on the subject is well illustrated in an AIME publication.' Although the presence of errors is readily admitted, their magnitudes are not known and often are described by practical operators merely as "great," "small," or "of no importance." The belief that errors are of academic interest only prevails because of a justifiable claim that actual volumes of air circulated are well in excess of those required by law and safe mining practices. Poor understanding of the source and nature of errors inherent in velocity measurements, coupled with questionable determination of cross-sectional area, result in faulty techniques for the purpose of expediting ventilation surveys and render doubtful the calculated volume. Often consistency of readings is confused with accuracy. A succession of check readings showing a maximum deviation of 5 pct in the measured value of velocity usually signifies nothing more than diligent application of technique in a stable ventilating current.

Nov 1, 1955

By GUY B. HUNNER

THOSE magnetite ore bodies comprising the Clifton Mines are situated in the south central part of St. Lawrence County, New York, on the western slope of the Adirondack Mountains. The topography is made up of gently rolling hills densely wooded with second-growth maple, birch, and hemlock. Drainage is north and west to the St. Lawrence River.

Jan 1, 1943

By H. F. Seifert

The classification and preparation of non-ferrous scrap mctals is a subject of interest to every individual and corporation that employs in its processes of manufacture non-ferrous metals and alloys and accurnulates in such manufacture scrap from these materials for disposition in the form of turnings, borings, short ends, punchings, clippings, grindings, washings, etc. All too frequently the disposition of such scrap is left to indivitluals who have no knowledge of the subject either from a metallurgical or a commercial standpoint, or both. Much money is thus lost whicli with a little more intelligent effort might be saved, and in this day of fierce competition and small profits such an opportunity cannot be ignored. The Mineral Resources of the United States for the year 1925, the latest issue available (Part 1, page 221), gives the secondary non-ferrous metals of certain classes recovered in the United States for the year 1924 to 1925 as shown in Table 1. The figures are tabulated simply to give the reader some idea of the scope of the secondary non-ferrous metal industry. Approximately 900,000 tons of an annual value of $244,000,000 were recovered in the year cited. In 1916 (again using thc Mineral Resources of the United States as authority) the tonnage reclaimed was approximately 632,000 tons and the value, because of the high prices for metals prevailing at that time, amounted to $265,000,000. It is not the purpose of this paper to discuss smelting and refining operations or the feasibility of an organization, primarily engaged in some other activity, conducting smelting and refining operations to convert its own non-ferrous scrap metals and alloys. The classification and preparation of these non-ferrous materials is a preliminary step, regardless of what subsequent operations the material may pass through or where these operations may be conducted. For that reason the subject can he readily discussed without any reference to subsequent activities. Space must be provided, with suitable handling facilities, scales and the necessary storage bins where the material may be accumulated. The scope of the activity, the nature of the industry and the tonnage handled will determine, in a large measure, what preparation, if any, it rrlay he desirable to give these scrap materials to put them in the best niarketable condition. By preparation is rneant largely what, for the want of a

By Roy P. Full, Robert M. Grantham

Regional structural adjustments in early Tertiary time resulted in the development of the Republic graben, a major down-dropped block that is from 6 to 10 miles in width and more than fifty miles in length. The graben became the center of extensive volcanic activity during Eocene and Oligocene time, resulting in a thick sequence of water-laid tuffaceous sediments, volcanic flows, and associated intrusives. A younger series of sediments, pyroclastics, and flows were deposited in structural depressions within the graben following the period of widespread volcanic activity. The Republic mining district is located along one of the major intragraben structural zones, where continuing subsidence during the period of volcanic activity resulted in an increased thickness of flows and associated flow breccias and pyroclastics. Intrusive masses in part healed early graben-forming faults, but later subsidence reopened old faults and created new fracture zones which later became the control for the gold-quartz veins. Considerable block adjustment along the subsidence area is evidenced by the structural pattern in the mines, and telescoped vein structures indicate north-south compressional stresses and east-west graben-forming tensional stresses prior to and during the emplacement of the veins. The veins, varying from a few feet to more than 50 feet in width, are filled primarily by fine-grained quartz, commonly chalcedonic or porcelain-like in appearance. Finely laminated dark-gray to black concentric banding within the veins generally distinguishes the better-grade ore zones, which contain finely disseminated sulfides and ore minerals that include principally electrum, stephanite, naumannite, and native silver.

Jan 1, 1968

By S. B. King

IT is the purpose of this article to give those not familiar with the subject an idea of the extent to which coal is mined by machine in the United States; to describe some types of electrically operated coal cutters; and in particular, some of the latest improvements and developments in these machines. Generally speaking, the article deals with the mining of bituminous coal in room-and-pillar mines, as the use of undercutting machines in the anthracite region of Pennsylvania is in its infancy, and when machine mining is referred to bituminous coal is taken for granted. The number of mines in the United States that are operating on the long-wall principle is very limited, and the number of long-wall machines in use is a very small percentage of the total. The advantages of mining by machine may be summed up briefly as follows: A. Increased safety to property and life, due to the large decrease in the amount of powder required when the coal is properly undermined. B. Reduction in the cost of mining. C. Improvement in the quality of the product; and, consequently, increase in market value, due to the greater proportion of lump and screen sizes secured by machine mining. D. Increase in the capacity of the mine, and more rapid development of new mines. E. Ability to mine veins in which the height of the coal or the character of the roof has prevented mining by hand, on a commercial basis.

Jan 6, 1914

For handling rough rock, the shovel-train system is unexcelled. The ideal application is a physically large, but not excessively deep, open-pit mine from which the coarsely blasted ore and waste must be transported distances in excess of three miles. If, in addition, a high production rate is to be maintained, railroad haulage will probably afford a lower cost per ton transportation than will any other haulage method. Relatively gentle grades must be employed- usually 3% for uphill hauls and 4% for downhill hauls. The greater the differences in elevation the greater are the railroad track grade space requirements. By way of illustration, a 3% ramp out of a pit only 300 ft deep must be almost two miles long. Mainline track locations should be selected carefully so that the frequency of movements during the life of the mining operation is minimized. This applies both to ore and to waste haulageways. Such moves are not only expensive but difficult to execute without adversely affecting production rates. The large mine affords greater opportunities for judicious location of semi-permanent trackage.

Jan 10, 1967

By J. E. Berg

THE geology of the Coeur d'Alene mining district is so familiar to every one interested in mining that I will only note as an introduction that the main producers are mines whose orebodies lie in the Revett or Burke quartzites ; that the known orebodies in the eastern part of the district all lie north of the Osburn fault; that the Prichard formation is quite generally looked upon as being unfavorable for lead deposits ; that the monzonite intrusive mass extending north from Gem to Sunset Peak, and over into Cedar Creek divide, is considered to have been the prime agent in the crea-tion of our orebodies, and that diabase dikes are a quite common feature at most of the properties with which I am familiar. Some of the exceptions to these statements may be mentioned. The Interstate-Callahan mine is considered the exception disproving the alleged relation between large ore-deposits and the Prichard formation, but this property was primarily a zinc producer, with lead secondary, though of sufficient tonnage to be a valuable product. A second interesting occurrence in the Prichard worth calling to your attention is the Jack Waite property, on Tributary Creek, north of Murray. This vein lies at a low horizon in the Prichard forma-tion, and the ore differs essentially from others in the same horizon elsewhere in that it is a clean, medium to coarsely crystalline, lead ore carrying very little zinc, about one ounce silver to ten units lead, and is accom-panied by a clean quartz gangue or vein filling. I believe that quartz was the primary mineral in the fissure, and that the lead ore was deposited in the vein as a replacement of the quartz.

Jan 7, 1927

By W. P. Barba

IN THE early summer of 1917, it became evident that the then existing sources of supply of guns and gun forgings were totally inadequate for the enormous and rapidly growing requirements of the Ordnance Department of the Army, so arrangements were made with sixteen makers of other products to take up the manufacture of guns and gun forgings. Nine of these makers were required to produce their own steel from the raw materials and convert it into rough machined gun forgings; the others finished and assembled these forgings into completed guns. In December, 1914, four of these makers of steel and rough gun forgings were instructed to manufacture the same amount of the 6-in. and 9.5-in. guns and howitzers. It, therefore, seemed practical .and profitable to assemble these makers into a small group, together with the officers of the Ordnance Department, and provide standard 'equipment in each of the four works for the production of these two types of guns. The advantages of this cooperation were immediately manifested, and there commenced an interchange of shop practice and a free discussion of facilities and methods that covered not only the equipment but the manufacturing processes.

Jan 1, 1920

By Charles B. Dudley

THEO. N. ELY, Esq., Superintendent of Motive Power. DEAR SIR: It is now nearly three years since my first report to you on the subject of steel rails was written. That report, as you will remember, dealt principally with the question of the relation between the chemical composition and physical properties of steel rails and their power to resist crushing and fracture in actual service. Other matters were referred to or touched upon in that report, but the main question was, Why do some rails crush or break in service while others do not? You will doubtless remember that the principal conclusion arrived at was, that the softer rails are less liable to crush or break in service than the hard ones. Or, in other words, so far as conclusions could be drawn from the chemical analysis and physical test of 25 samples of steel rails which had actually been in service, these conclusions were that those rails which have the smaller amounts of carbon, phosphorus, silicon, and manganese are less liable to crush or break in service than those which have larger amounts of these elements. Or, again, looked at in the light * At the Lake George meeting of the Institute in October, 1878, I had the honor of presenting to the Institute, through the kind permission of the officers of. the Pennsylvania Railroad Company, the results of a study of twenty-five samples of steel rails, which had all been in actual service. Considerable discussion followed the publication of that paper, and there seemed to be a strong disinclination, especially on the part of the steel-rail manufacturers, to accept the conclusions presented. One of the principal objections urged against the conclusions drawn was, that they were based on too few samples; in other words, that no conclusions safe to act upon could be drawn from the examination of twenty-five rails. In view of this criticism it was decided to repeat the investigation with a larger number of samples, and with the aid of the experience gained in the first investigation. The results of this second study of steel rails are, by the permission of the officers of 'the Pennsylvania. Railroad Company, herewith presented to the Institute, with the sincere desire that they may aid in adding to our knowledge of this most important product. Like the previous paper, this is in the form of a report to one of the officers of the company, which will account for the style, and the manner of presenting the data

Jan 1, 1881

By E. H. Dix

The work of Merical and other investigators indicates that the phenomenon of age-hardening in alloys of the duralumin type is primarily dependent upon the variation in the solubility of copper with temperature. In addition to copper, however, these alloys contain small amounts of magnesium, silicon, manganese and iron, which may affect the age-hardening either directly or indirectly. The effect of these elements on the solubility of copper and on the manner in which this solubility varies with the temperature is of considerable interest, therefore. The effect of magnesium is of especial interest because apparently it exerts a marked effect on the natural or room-temperature aging of alloys of the type described.2 A series of investigations3 has been in progress in the research laboratories of the Aluminum Company of America to determine the functions * Metallurgist, Aluminum Research Laboratories. f Metallurgical Division, Aluminum Research Laboratories. Formerly with Metallurgical Division, Aluminum Research Laboratories. 1 P. D. Merica, It. G. Waltenberg and H. Scott: Heat Treatment of Duralumin. U. S. Bur. Stds. Sn. Paper 347 (1910). 2 M. Gayler: Constitution and Age-Hardening of Alloys of Aluminum with Copper, Magnesium, and Silicon in the Solid State. Jnl. Inst. Met. (1922) 28, 213. W. Fraenkel: Vergutbare Aluminiumlegiengen. Ztsch. Melallkunde. (1920) 12, 427. E. H. Dix, Jr.: Note on the Microstructure of Aluminum-Iron Alloys of High Purity. Proc. Amer. Soc. Test. Mat. (1925) 26, Pt. 2, 120. E. H. Dix, Jr. and H. H. Richardson: Equilibrium Relations in Aluminum-copper Alloys of High Purity. Trans. A. I. M. E. (1926) 73, 560. E. H. Dix, Jr. and W. D. Keith: Equilibrium Relations in Aluminum-manganese Alloys of High Purity. Proc. Inst. Met. Div., A. I. M. E. (1927) 315. E. H. Dix, Jr. and A. C. Heath, Jr.: Equilibrium Relations in Aluminum-silicon and Aluminum-iron-silicon Alloys of High Purity. Proc. Inst. Met. Div., A. I. M. E. (1928) 164. E. H. Dix, Jr. and F. Keller: Equilibrium Itelations in Aluminum-magnesium Alloys of High Purity. Proc. Inst. Met. Div., A. I. M. E. (1920) 351. E. H. Dix, Jr., F. Keller and R. W. Graham: Equilibrium Relations of Aluminum-magnesium Silicide Alloys of High Purity. Trans. A. I. M. E., Inst. Met. Div. (1931) 404. W. L. Fink and K. R. Van Horn: Constituents of Aluminum-iron-silicon Alloys. Trans. A. I. M. E., Inst. Met. Div. (1931) 383.

Jan 1, 1932

By E. E. White

In August, 1911, I read a paper before the Lake Superior Mining Institute1 on surveying and sampling diamond-drill holes. The present paper gives a more thorough descriptiou of these methods, together with a few changes and notes suggested by further experience. Since August, 1911, the methods, used constantly by the Cleveland-Cliffs Iron Co., have been developed to a higher degree of efficiency, and have given great satisfaction. Until a few years ago but little attention was paid to the determination of the actual course of drill-holes, to the accurate sampling' and analysis of the material, or to the scientific location of the drill-holes. It has now been common practice for several years in many districts to test the inclination of drillholes by etching glass tubes with hydrofluoric acid, but the direction of deviation from the vertical has not often been determined. Methods of determining the direction by means of a compass were first developed in connection with drilling in Victoria. The latest method used on the Rand in South Africa has been recently described by John I. Hoffman.2 In the same paper Mr. Hoffman describes an ingenious method of wedging-off a drill-hole so as to start new holes at several successive points. By this means a hole can be deflected in any desired direction, and the curvature can be controlled to a considerable extent, provided the rock is soft enough to permit the hole to be wedged off. Unfortunately, in the Lake Superior district, the jasper iron-formation is so hard that it is very difficult, if not impossible, to do this. I tried to deflect one hole so as to avoid drill-rods stuck in the hole, by using a

Jan 1, 1913

By William M. Baldwin

Jan 1, 1946