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By C. Upthegrove

DURING the past year considerable work dealing with physical properties of cartridge brass was done at the University of Michigan in cooperation with the Ordnance Department of the U. S. Army. This paper gives some of the data bearing on the effect of the anneal, previous to the final reduction or rolling, on the physical properties, particularly the hardness. Various phases of the subject of physical properties of cartridge brass have been presented by different investigators. Mathewson and Phillips1 refer to the work of Grard, in 1909, as the first systematic presentation of the relation between temperature-and time of anneal; changing of physical properties and microstructure, and the previous reduction by cold rolling. They discuss the relation between time and temperature of anneal and the previous reduction by cold rolling also; the relation between physical properties and grain size of annealed brass. The degree of deformation previous to the annealing was found to determine the temperature at which recrystallization and corresponding changes in physical properties would take place. Bassett and Davis,2 in establishing the relation between grain size and Brinell hardness; found the hardness for low-temperature annealing to be dependent on the previous degree of reduction, while for anneals above a certain temperature the hardness after the anneal was independent of the degree of reduction. Actual differences in hardness, due to the degree of reduction, disappear only on annealing at 600° C. or above; though the differences for metal subjected to different degrees of reduction and annealed at temperatures between 350° and 600° C. were found to be relatively small. In their determination of the relationship of grain size to Brinell hardness, Bassett

Jan 5, 1922

By J. W. Littleford

The Roan Antelope Copper Mines Ltd. are situated in the north central part of Northern Rhodesia, at an altitude of 4000 ft. and 13" south of the Equator. The town site (Luanshya) is well situated and enjoys among other things a really temperate climate for 10 months of the year. The two spring and summer months, October and November, while hot and humid, do not bring any great discomforts as compared with many other mining camps. Strictly modern brick homes, with electric lights, purified water, telephone and water-borne sewage, add to the comfort of the employees. A rainfall of approximately 60 in. per year furnishes ample water for both industrial and domestic purposes. The rainy season generally begins in October and lasts through until March. As much as 3 to 4 in. is recorded in 24 hr., but this offers no difficulties because the runoff is very rapid. The property is connected by a 24-mile branch line from Ndola with the main line of the Beira-Mashonaland and Rhodesia Railways Ltd. Practically all supplies from overseas are transported over this line from Beira, 1743 miles distant on the east coast in Portuguese East Africa. The mine output also leaves Africa from this port. Passenger service is principally via Cape Town or Durban, a distance of about 2100 miles to either port. The Imperial Airways maintain a service from Cape Town to Croydon, taking 9 days for the trip. Connections can be made with this service at Broken Hill, 150 miles south of Luanshya, by either rail or automobile. Thus, after several days of travel through virgin bush, a visitor arrives at a typically modern town site in the heart of Africa. Every development in mining, milling and smelting practice is used to advantage. Plan of Mill The practice in the three principal phases of the production of copper from the ores of this company have been published from time to time. Milling practice, however, is continually changing and what may be

Jan 1, 1935

By Kenneth Cottingham

The year 1941 brought a considerable increase in drilling activity in Ohio. In 1940, the total of wells completed was 1228, whereas in 1941 it was 1561, or an increase of approximately 27 per cent. Of the 1561 wells, 333 were oil wells, 701 gas wells and 527 dry holes. The completions for the past five years are shown in Table I; the number of productive oil or gas wells for the year 1941, arranged by producing formations, are given in Table 2; the number of wells, oil, gas or dry, completed in each county in 1941, in Table 3, and wells by sands in Table 4. The production of oil increased by about 500,000 bbl. in 1941, nearly all of the increase being in Pennsylvania grade. In 1940, the total production was 3,052,000 bbl. from 25,500 wells. In 1941 the total production was 3,547,534 bbl. from 24,801 wells. The increase in production is chiefly due to the Clinton pool in Clayton township, Perry County, which is briefly men- tioned later in this review. The number of oil wells, by grades of oil, and the total quantities produced are shown in Table ;. Annual oil production for five years is listed in Table 6. The average prices paid for crude in 1941 were slightly higher than in 1940 These 1941 prices, with dates of change, are shown in Table 7. The maximum production of natural gas in Ohio was in the year 1915, when the total was just under 80 billion cu. ft. The maximum consumption occurred in the year 1916, and was approximately 169 billion cu. ft. For the past several years, Ohio has ranged from eighth to eleventh, in order of gas production for the different states, being in tenth place in 1940. In the matter of consumption, however, Ohio remains in fifth place. Preliminary figures for 1940 indicate that production of natural gas increased II per

Jan 1, 1942

By Wilbert McBride

Two Alco 3 ½ -ton motor trucks were used by Young Bros. while operating at the Mammoth Collins mine at Shultz, Ariz. One was equipped with an oil tank holding 1,075 gal. and was used for the transportation of "tops." The, other was fitted with a stake body and used to carry machinery, wood, rails, pipe and all classes of miscellaneous supplies. The bodies were made of oak with maple flooring and were attached to the frame of the chassis by U-bolts, to avoid drilling the main members of the frame. Most of the hauling was done from Tucson, a distance of 47;2 miles. During the first. 3 months, part of the road was in very bad condition and the tire cost was excessive. After this part was repaired the road was in fair condition, but never good. There were no excessive grades or bad sand, but wagon ruts, too narrow for the truck wheels and of a different gage, caused heavy tire loss; while chuck holes, sharp curves and stones, both imbedded and loose, were objectionable features. During wet weather the trucks could not get sufficient traction to climb some of the hills and were likely to stick in the mud in certain places, so that no attempt was made to run them unless they were on the road when the rain started. This lost time amounted to about 5 per cent. of the total, but, whenever possible, it was utilized in making minor repairs. The price of gasoline, was from 17 to 21 c. per gal. Rubber tires were used throughout. Drivers were paid $4.50 to $5 per shift, and a return trip to Tucson was counted as two shifts even when made in one day. Drivers were provided with a room in Tucson and were paid for all time lost due to causes beyond their control. Trucks were loaded one way only.

Jan 7, 1916

By Kenneth Cottingham

The year 1941 brought a considerable increase in drilling activity in Ohio. In 1940, the total of wells completed was 1228, whereas in 1941 it was 1561, or an increase of approximately 27 per cent. Of the 1561 wells, 333 were oil wells, 701 gas wells and 527 dry holes. The completions for the past five years are shown in Table I; the number of productive oil or gas wells for the year 1941, arranged by producing formations, are given in Table 2; the number of wells, oil, gas or dry, completed in each county in 1941, in Table 3, and wells by sands in Table 4. The production of oil increased by about 500,000 bbl. in 1941, nearly all of the increase being in Pennsylvania grade. In 1940, the total production was 3,052,000 bbl. from 25,500 wells. In 1941 the total production was 3,547,534 bbl. from 24,801 wells. The increase in production is chiefly due to the Clinton pool in Clayton township, Perry County, which is briefly men- tioned later in this review. The number of oil wells, by grades of oil, and the total quantities produced are shown in Table ;. Annual oil production for five years is listed in Table 6. The average prices paid for crude in 1941 were slightly higher than in 1940 These 1941 prices, with dates of change, are shown in Table 7. The maximum production of natural gas in Ohio was in the year 1915, when the total was just under 80 billion cu. ft. The maximum consumption occurred in the year 1916, and was approximately 169 billion cu. ft. For the past several years, Ohio has ranged from eighth to eleventh, in order of gas production for the different states, being in tenth place in 1940. In the matter of consumption, however, Ohio remains in fifth place. Preliminary figures for 1940 indicate that production of natural gas increased II per

Jan 1, 1942

By A. J. Miller, G. R. Brophy

THE Grossmann principle1 for the calculation of hardenability of steel from composition is attractive because of its simplicity. It postulates that the hardenability of a steel for any particular grain size may be expressed in terms of an ideal critical diameter, which is the product of an ideal critical diameter for a "pure" iron-carbon base multiplied by a succession of factors for each element of composition contained, including the incidentals. It infers that the multiplying factor for a given quantity of an element is constant for all combinations of composition. Grossmann has stated that in the great majority of cases the experimental values of hardenability are found to be well within 10 per cent of the calculated values. The validity of the scheme has been confirmed in principle by Crafts and Lamont2,3 and by Kramer et al .4 Their results differ from the original in the magnitude of the effect of some elements but, since they accepted the product concept and followed its direction, it is to be expected that similar results would be obtained. Crafts and Lamont, in their second paper, recognized that the factor relations for manganese and nickel were not continuously linear, but beyond certain critical amounts increase sharply. Austin, Van Note and Prater5 demonstrated nonlinear relations between hardenability and alloy contents. Their curves for chromium, silicon, manganese and nickel were all convex upward to show decreasing incremental effects. They concluded that Grossmann's factors underevaluate the hardening effect of low percentage additions of these elements, and overevaluate the larger additions. [ ] More recently W. Steven6 has found that the factor method fails when applied to complex steels containing two or three principal alloying elements other than carbon. Multiplying factors derived from his results bear a complex relation to composition and are not constant for a given amount of an element as the base composition varies. C. A. Liedholm7 found that, using either the Grossmann or the Crafts-Lamont multiplying factor values, not only were

Jan 1, 1945

By C. P. Melloy

INTRODUCTION Ventilation practice at Isa Mine has been evolving since underground mining began in 1931. Much fundamental work has been conducted and reported regarding the primary ventilation system [Mathews K.E. et a1 (1967) and Brown J.R., Fisher T.H., Gibson K.L. (1979) 1. However, ventilation networks for subsystems such as open stopes, have evolved with experience. This paper outlines current ventilation practice for open stoping. Mount Isa Mine The mine is located in semi-arid North-West Queensland, Australia, and currently produces 20 000 tonnes of copper ore and 10 000 tonnes of silver-lead-zinc ore daily in each five day working week. Mining extends over a north-south strike length of 3.5 km with a maximum width across dip approaching 1 km, and is to a depth of 960 m (Figure 1). At present approximately 90% of the mine's copper production is from the 1100 Orebody, which contains ore reserves of 121 million tonnes of 3.2% copper. Open stoping is currently the mining method employed, and is used for primary stoping and pillar recovery adjacent to cement fill walls. The development of stoping methods in the 1100 Orebody has been documented by Kirkby R.W., Blair J.R., and Hutton R.C. (19781, Hornsby B. and Sullivan B.J. (1978), and Alexander E.G. and Fabjanczyk M.W (1981). As many as thirteen open stopes may be producing concurrently in the Orebody (Figure 2). The multiple silver-lead-zinc orebodies containing reserves of 54 million tonnes of 150 g/t silver, 6.4% lead and 6.5% zinc, are mined by open stoping, and cut and fill techniques. These methods have been documented by Goddard I.A. and Bridges M.C. (1977 1, and Goddard I. A. (1981 1. Only the ventilation of the 1100 Orebody open stopes will be discussed. However, the same ventilation philosophy is employed in open stope design in the lead orebodies.

Jan 1, 1981

By H. I. Aaronson

The nucleation of pearlite at proeutectoid ferrite is inhibited, to an increasing extent, at the following locations: At twin boundary-nucleated ferrite, between closely spaced ferrite sideplates, and at intragranular plates. These effects are discussed in terms of the influence of transformation strain energies and of the interfacial free energy of austen-ite:ferrite boundaries on the rate of pearlite nucleation. The growth of pearlite into the interiors of austenite grains from the region of the grain boundaries is markedly restricted when low reaction temperatures and large austenite grain sizes permit the development of interlocking networks of intragranular ferrite plates. PREVIOUS investigators have made extensive studies of the interactions which occur between the proeutectoid ferrite and the pearlite reactions from the viewpoint of the mechanisms through which pearlite interferes with the nucleation and growth of proeutectoid ferrite.1-3 In the present investigation, the processes through which proeutectoid ferrite (hereafter termed simply "ferrite") can reduce the rate of formation of pearlite have been explored in some detail. A steel with a relatively low carbon content, in which the ferrite reaction can compete successfully with the pearlite reaction over a wide range of reaction temperature, and exceptionally coarse-grained specimens, which further emphasize the role of the ferrite reaction, have been employed for most of this work. A brief examination also has been made, however, of the effects of smaller austenite grain sizes upon these processes. Experimental Procedure The steel employed had the following composition: 0.29 pet C, 0.76 pet Mn, 0.25 pet si, 0,007 pet S, and 0.005 pct P. This alloy was homogenized for 48 hr at 1250°C. The investigation was performed

Jan 1, 1959

By Shosei Serata

Stress control methods of mining have been developed separately in at least four different parts of the world in entirely different types of mining -- coal, trona, salt and potash -- during the decade of the 1960s. They all utilized yield pillars as tools for ground control. Today, yield pillars are becoming widely used in under- ground mines in a variety of geological conditions. Stress control methods are effective in stabilizing openings in weak, complex grounds, especially at greater depths. Their advantage is that they utilize existing ground media to stabilize mine openings by altering the stress distribution patterns around the openings, by controlling design parameters such as room width, pillar geometry, and excavation sequence, rather than by using a conventional means of artificial ground support such as roof bolts, cribbing, or arches. Stress control methods, therefore, are suitable for both advance and retreat mining, including total extraction mining. Adaptation of these methods results in substantially greater safety, productivity, and ecnomy over conventional methods. These methods are based on scrutiny of the actual stress conditions in the ground, by both in-situ measurement and computer simulation. This paper provides a summary of stress control methods as developed over the last ten years. The field examples are limited largely to salt and potash mining applications, although the method has been used successfully in other mining applications. The examples illustrate that stress control methods actually address general ground weakness problems -- separation at discontinuity planes, swelling by shale expansion, deterioration by brittle fracture, and interference by ground water. That is, although the principle is developed mainly with reference to salt and potash applications, it is generally applicable to weak ground.

Jan 1, 1983

By Edward W. Parker

Note.—The material from which this paper has been prepared was collected tor the U. S. Geological Suvey Bulletin, No. 316, Contributions to Economic Geology, 1906, and appears also, though in somewhat more extended form without illustrations, in that publication. Although the briquetting of coals and lignites has been carried on for many years in Europe, and has reached a particularly high state of development in France, Belgium, and Germany, it has made comparatively little progress in the United States. The causes for the backwardness of the United States in this regard are several, and first among them has been the abundant supply of cheap raw fuel with which the manufactured article has to compete. With our millions of acres of coal-productive territory, from which the product can in moat cases be cheaply extracted, it has appeared in many districts more economical to waste the slack or culm, which constitutes a considerable percentage of the product, than to attempt to save it at the additional expense required for briquetting. It is for this reason that the view in all sections -of the anthracite-region of Pennsylvania is marred by the unsightly culm-banks which encumber the ground, and that in some of the bituminous-districts one sees huge piles of unmarketable slack allowed to burn up in order to get rid of them. When the coal is of a coking quality, or when the slack can be used for steaming-purposes, these losses are not sustained, but many thousands of tons of what might be converted into usable fuel have been wasted every year simply because of the increased expense involved in its preparation.

Jan 1, 1908

By R. A. Wagstaff

Many changes in equipment have had to be made to handle the flotation products at the blast furnace, and these changes have meant an expenditure of considerable money, which has not been compensated by an increase in smelting tonnage. To date, very few new lead mines have been developed, so that the help derived by the innovation of flotation has been directed to old producing properties, where the ratio of concentration is greater now than when gravity concentration was in effect. In some smelting plants there has been an abandonment of complete units due to the introduction of flotation. Flotation Products Difficult to Handle The physical characteristics of the flotation product do not make for economic handling for lead blast-furnace work, either mechanically or metallurgically. The millman or miner do not know what trials and tribulations they have passed on to the smelterman. To the smelterman it is "the everchanging flotation," for little does he know what new reagent will be perfected tomorrow that may completely change the grade and physical characteristics of the product. Even the mining companies who have complete units of mining, milling and smelting have had a hard time to reconcile themselves to the fact that the unit cost per ton of ore smelted must go up with the increase of flotation product on the blast-furnace charge. The "smelterman's burden," for that is what flotation has been for the last few years, has not caused the smelter operator to lag or fall down, but has spurred him on with new zeal. The physical properties of the flotation products are as follows: (1) High moisture content; (2) mucky nature of product; (3) fineness of product, and (4) high metal content. New Mechanical Devices for Handling Furnace Product These characteristics have caused the use of many new mechanical devices in smelting practice, for example: New transportation equipment, such as solid-bottom cars, is required; unloading equipment and sampling

Jan 1, 1928

By Walter O. Snelling

In combating mine-fires the use of carbon dioxide as a means of producing an atmosphere in which combustion cannot be sustained, has been many times suggested and frequently tried, generally with a fair degree of success. The carbon dioxide is produced by acting on limestone with dilute sulphuric acid, large wooden boxes being used to hold the limestone, and arranged in such a manner that one box may be cleaned and refilled with blocks of limestone while another is being used in generating the carbon dioxide.. The gas is led by means of pipes of large diameter to the location of the fire, tight brattices having been previously put up as close to the fire as possible on every side, so as to limit the space to be filled with the gas to the smallest possible volume. The cost of producing carbon dioxide has been, however, a decided draw-hack to the use of this method, and the danger of producing carbon monoxide by the reduction of the carbon dioxide by heated carbon, and consequently bringing about an explosion, has also tended to prevent the application of this method. The use of sulphur dioxide in combating mine-fires has not, I believe, been previously suggested or tried, and yet the method presents such decided advantages over the use of carbon dioxide that it seems proper to suggest the advisability of considering it as a cheap, convenient, and safe means of fightr ing stubborn mine-fires. 1. Cost, Preparation, etc.—One ton of brimstone, costing from $20 to $30, will produce about 25,000 cu. ft. of sulphur dioxide gas, and allowing for all sources of loss it is probable that sulphur dioxide gas can be produced for about $1,300 per 1,000,000 cu. ft. For carbon dioxide gas, produced by the action of sulphuric acid on limestone, a good estimate would be $4,000 per 1,000,000 cu. ft., provided that sulphuric acid

Jan 1, 1909

By B. E. Thompson, H. B. Fuqua

The area discussed herein, commonly known as the North Texas district, embraces the following 10 counties: Archer, Baylor, Clay, Cooke, Foard, Hardeman, Knox, Montague, Wichita and Wilbarger. It is underlain by two major structural features. The northernmost portion of the district, including Coolie, Montague, northern Clay, Wichita, Wilbarger, Foard and Hardeman Counties, is underlain by the system of buried mountains known as the Red River uplift, which is parallel to and closely related to the Wichita-Amarillo uplift of Oklahoma and the Texas Panhandle. While the presence of a great majority of the numerous oil fields of the area is traceable to this feature, the production in Archer, southwestern Clay and southeastern Baylor Counties is due to the influence of what is known as the Cisco arch (so called because of its influence on Cisco deposition), the axis of which extends in a northwest-southeast direction across southwestern Wichita County into Archer County. Developments during 1938 Important discoveries in the district were considerably more numerous and of more economic importance than for several years. In addition to a number of small, relatively unimportant discoveries and to the usual local extensions to the various producing fields in the several counties, at least eight fields, most of them apparently of considerable areal extent and importance, were found. The Helmerich and Payne, Incorporated and Blackwell Oil and Gas Company No. 1 Wilson. 4 miles southeast of the town of Holliday, in north central Archer County, encountered a pay of Strawn age at a depth of 3841 to 3858 ft., and was completed for an initial production of 1952 bbl. T'his well opened a new deep pool in the K. M. A. producing zone 8 miles southeast of the K. M. A. production. Subsequently an additional deeper horizon, also of lowcr Strawn age, was discovered by wells that failed to yield commerecial oil from the horizon of the discovery well.

Jan 1, 1939

By John W. Cloud

IN 1877 the Pennsylvania Railroad Company removed an old bridge from its line at Duncannon, Pa., built intermediate piers and erected shorter spans of the Pratt truss type, which had previously been in use on another portion of the road. The design of this truss would not admit of diagonals larger than 1 5/8 inches diameter, and in order to stiffen the bridge somewhat steel rods were introduced for the main diagonals in the first and second panels, 1 5/8 inches and 1 3/8 inches diameter respectively. These rods were threaded without upsetting, and by the ordinary formulae the strains were of the same intensity upon both, viz., 16,000 pounds per square inch with the maximum loading. The other main diagonals in the truss are 1 5/8 inches diameter, and of iron. It was specified for the steel rods : Elastic limit, - 45,000 lbs. Tensile strength, - 80,000 lbs. Elongation, - 20 per cent. The steel was procured without difficulty, and it allowed a factor of safety of 2 3/4 at elastic limit, while a similar factor of 2 1/2 had for a long time been successfully used for iron. In the course of three years, from time to time, six of these steel rods broke, three of them being 1 3/8 inches in diameter, and three 1 5/8 inches in. diameter. The broken rods were tested, and three of them. analyzed at Altoona to ascertain the cause of failure, and what modi¬fications should be made in the steel for such service. Examination showed that all the rods were broken in detail close under the nut. The threads were well cut and properly rounded at the root. In testing the rods micrometer screws,. reading to .0001" with electric bell to signal the contact, were attached to the test pieces, and by this means the modulus of elasticity and elastic limit accurately obtained.

Jan 1, 1881

By H. B. Fuqua, B. E. Thompson

The area discussed herein, commonly known as the North Texas district, embraces the following 10 counties: Archer, Baylor, Clay, Cooke, Foard, Hardeman, Knox, Montague, Wichita and Wilbarger. It is underlain by two major structural features. The northernmost portion of the district, including Coolie, Montague, northern Clay, Wichita, Wilbarger, Foard and Hardeman Counties, is underlain by the system of buried mountains known as the Red River uplift, which is parallel to and closely related to the Wichita-Amarillo uplift of Oklahoma and the Texas Panhandle. While the presence of a great majority of the numerous oil fields of the area is traceable to this feature, the production in Archer, southwestern Clay and southeastern Baylor Counties is due to the influence of what is known as the Cisco arch (so called because of its influence on Cisco deposition), the axis of which extends in a northwest-southeast direction across southwestern Wichita County into Archer County. Developments during 1938 Important discoveries in the district were considerably more numerous and of more economic importance than for several years. In addition to a number of small, relatively unimportant discoveries and to the usual local extensions to the various producing fields in the several counties, at least eight fields, most of them apparently of considerable areal extent and importance, were found. The Helmerich and Payne, Incorporated and Blackwell Oil and Gas Company No. 1 Wilson. 4 miles southeast of the town of Holliday, in north central Archer County, encountered a pay of Strawn age at a depth of 3841 to 3858 ft., and was completed for an initial production of 1952 bbl. T'his well opened a new deep pool in the K. M. A. producing zone 8 miles southeast of the K. M. A. production. Subsequently an additional deeper horizon, also of lowcr Strawn age, was discovered by wells that failed to yield commerecial oil from the horizon of the discovery well.

Jan 1, 1939

By Fred W. Gordon

The North Chicago Rolling-Mill Co., of Chicago, have four furnaces at South Chicago, built during 1881. Each furnace is 20 feet diameter of bosh, and 75 feet total height, the hearth being 11 feet diameter, and the top 15 feet 4 inches. They are blown through seven 7-inch tuyeres placed 5 feet 6 inches above the hearth level. Cubical contents, 15,000 cubic feet. Each furnace is supplied with 2 blowing engines, 84-inch blowing cylinder, and 36-inch steam cylinder, and 54-inch stroke. These two have one jet-condenser worked by an auxiliary pump. The blast for each furnace is heated by the aid of three Whitwell fire-brick stoves, each 21 feet diameter and 60 feet high. In the batteries of boilers furnishing steam for four furnaces there are 36 double-length boilers, 76 feet long, 48 inches diameter and 16,000 square feet heating-surface. The plant was designed to produce 3600 tons per week, or 900 tons for each furnace, and was fitted as above with such engines, boilers, and hot-blast stoves as were thought requisite for that production ; hence, calculated from the present make—not the least remarkable feature is the economy of construction—there are less engines, less boilers, and less hot-blast power for the iron made than at ally plant within my knowledge, or it could to-day be duplicated for less money per ton of iron made per week than could any plant now in existence, whether using fire-brick or cast-iron stoves for heating the blast. This is a practical demonstration of my assertion in a paper on fire-brick stoves, read before the Institute," that the application of fire-brick stoves in construction really lessens the first cost. In view of the statements just made, I must be most emphatic in assuring the members that nothing is strained or overburdened.

Jan 1, 1886

By Guilliaem Aertsen

The derivation of the word tire (or tyre, as it is spelled in England) is obscure. Some dictionaries suggest that it is the aphetic form for "attire, covering," so called as being the outside covering or band of a wheel; also as a corruption of "tier," the band which holds, or "ties," the rest of the wheel together. One dictionary states: "The supposed derivation of the word is that bands were first used on wheels in the City of Tyre, Syria." In the infancy of railroads, the tracks consisted of flat bars of iron, spiked or bolted to the upper surfaces of longitudinal timbers, which, in turn, rested upon masonry foundations. Stone blocks installed for this purpose on the old Germantown & Norristown Railroad, now the Chestnut Hill branch of the Philadelphia & Reading Railway, were to be seen for many years on the right-of-way, north of what is now Wayne Junction, Philadelphia, Pa. The "cornerstone" of the Baltimore & Ohio Railroad was laid Apr. 4, 1828, and the fist locomotive in America was built by Peter Cooper at the St. Clair Works, Baltimore, Md., in 1829 "to demonstrate its adaptability to a curved road." It is believed that the first successful locomotive was built in Philadelphia by Tyler & Baldwin in 1832 for the Germantown & Norristown Railroad. Rufus Tyler and Matthias Baldwin were brothers-in-law; the latter's name will be identified with American locomotives until locomotives are forgotten. The wheels on these first locomotives, designed to run on this primitive rail, mere shod with plain iron bands, bent and welded. The flanges consisted of separate iron bands, bent sidewise,welded, and bolted to the sides of the wooden fellies, or rims. Before many years had elapsed the tires were fabricated of iron bands, rolled in one piece with the flange projection on the side. The tire for each wheel was bent and welded and subsequently attached to the wheel center by shrinkage, bolts, rivets and various mechanical devices. Germany is generally given the credit for first making such tires of

Jan 1, 1917

By F. C. Dyer, H. E. T. Haultain

There has been much written on ball-mills, but no small amount of the literature is simply the expression of individual opinion without sufficient data. This is no doubt due to the complexity and obscurity of the phenomena involved. The outstanding paper is by E. W. Davis,I superintendent, School of Mines Experiment Station, University of Minnesota, which is based on a large amount of data from careful experiments with full-size apparatus, together with some mathematical philosophy. The entire philosophy is summed up in the equations given; but the present writers question the foundation upon which this philosophy is based. Encouraged by the work of Davis, the authors of this paper continued work they had been doing along this line. At first, photographs were taken of the ends of rods in a small laboratory rod mill. The mill was tilted slightly toward the feed end and the discharge end was removed. The rods remained in the mill long enough to permit good observation and good photography. Later, a mill 24 in. inside the stepped lining was constructed. It consisted of two sheets of plate glass, 1/2 in. apart, set in a cast-iron ring. It was driven by a variable speed motor and was connected to an accurate speedometer (magneto and voltmeter type). In place of balls or rods, cast brass disks were used. These were 3/8 in. thick and varied in diameter from 2 in. down to 3/4 in. Four small projections on each side prevented the disks sticking to the glass when water was used; sometimes steel balls % in. in diameter were added to the load of disks. There was also constructed a 6-in. mill with corrugated linoleum lining and containing a dry load of various sizes of steel balls. The mills were so connected to the motor that the small mill made two revolutions to one of the large mill. Many runs were made with a great variety of materials, including crushed marble, seeds of many kinds, and many mixtures (some wet and

Jan 1, 1923

By F. C. Dyer, H. E. T. Haultain

There has been much written on ball-mills, but no small amount of the literature is simply the expression of individual opinion without sufficient data. This is no doubt due to the complexity and obscurity of the phenomena involved. The outstanding paper is by E. W. Davis,I superintendent, School of Mines Experiment Station, University of Minnesota, which is based on a large amount of data from careful experiments with full-size apparatus, together with some mathematical philosophy. The entire philosophy is summed up in the equations given; but the present writers question the foundation upon which this philosophy is based. Encouraged by the work of Davis, the authors of this paper continued work they had been doing along this line. At first, photographs were taken of the ends of rods in a small laboratory rod mill. The mill was tilted slightly toward the feed end and the discharge end was removed. The rods remained in the mill long enough to permit good observation and good photography. Later, a mill 24 in. inside the stepped lining was constructed. It consisted of two sheets of plate glass, 1/2 in. apart, set in a cast-iron ring. It was driven by a variable speed motor and was connected to an accurate speedometer (magneto and voltmeter type). In place of balls or rods, cast brass disks were used. These were 3/8 in. thick and varied in diameter from 2 in. down to 3/4 in. Four small projections on each side prevented the disks sticking to the glass when water was used; sometimes steel balls % in. in diameter were added to the load of disks. There was also constructed a 6-in. mill with corrugated linoleum lining and containing a dry load of various sizes of steel balls. The mills were so connected to the motor that the small mill made two revolutions to one of the large mill. Many runs were made with a great variety of materials, including crushed marble, seeds of many kinds, and many mixtures (some wet and

Jan 1, 1923

By Stuart E. Buckley

The application of hydrocarbon equilibrium data to various problems encountered in refining and in natural gasoline recovery is an old and well established practice. Both generalized data and data on specific hydrocarbon systems have been made available by a number of investigators. More recently such data have been applied to the relations governing the separation of oil and gas both in the reservoir and at the surface. Most of the applications to production problems, however, have been based upon examinations of surface samples of oil and gas. This paper describes a technique that has been used satisfactorily in a number of cases to calculate directly from the hydrocarbon analysis of and auxiliary laboratory data on a subsurface sample of the reservoir fluid the behavior of the oil and gas during the various stages of separation at the surface incident to production. Types of Information Calculated The system of calculations is not designed to supplant field data, but rather to correlate with them laboratory data obtained under controlled conditions in order to obtain a more complete and exact picture than usually is possible through the use of field data alone. The chief advantage of the calculations is the possibility of their use at a minimum of both time and expense to determine completely the effect of any possible operating technique upon each of the following: (1) The gas-oil ratio resulting from liberation of the dissolved gas; (2) the composition and gasoline content of the liberated gas; (3) the composition and gravity of the residual oil; (4) the amount and composition of the gas liberated upon flashing the oil from the separator to the stock tank; (5) the shrinkage of the oil in passing from the reservoir to the stock tank. This information is frequently essential to the correct determination of the advisability of installing a natural gasoline plant, to design such a plant to take care of seasonal production, and to determine the optimum separator pressures to carry in various parts of a field.

Jan 1, 1938