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By W. T. Bishop

FOR many years pine oil has been used extensively as a frother for the flotation of minerals, particularly sulphides, yet the published information available to the average user on its composition, chemical and physical properties, has been rather meager. It is the purpose of this paper to discuss these points and their relationship to the frothing properties of pine oil used in flotation processes. Pine oil, as the name implies, is a liquid obtained from the processing of wood of the longleaf and other southern pines. It is a complex mixture of naturally occurring terpene derivatives, primarily alcohols, and a smaller amount of terpenes, which has found many uses in various industries. Its use as a frother in flotation processes was the first large-scale application in industry and today the mining industry still consumes large quantities of pine oil but the textile and disinfectant industries consume comparable volumes. Much is used in soap manufacture and laundry operations. The surface-active properties of pine oil are in a large degree responsible for this versatility. HISTORY The name "Naval Stores" goes back to the days when pine tar and pitch were used to caulk leaky ships and coat their ropes and rigging. Today this term is still used to include not only the oleoresinous products of the pine tree-rosin and turpentine-but other products such as pine oil, pine tar, and the many terpene and resinous compounds obtained by extracting the pine wood or tapping the tree. That part of the industry known as "wood naval stores" dates from about the beginning of this century and today produces a large part of the country's rosin and turpentine by processing pine wood. In addition, all of our natural pine oil is, supplied by the wood naval stores industry, as tapping of the live tree gives only rosin and turpentine. This latter phase is known as the "gum naval stores" industry. The first successful commercial operation of the steam and solvent process of the wood naval stores in industry was carried out by Yaryan at Cadillac, Mich., in 1909.1 This operation did not prove profitable, so Yaryan went south to utilize the longleaf pine, and built a plant at Gulfport, Miss.2 Soon after, another plant was built at Brunswick, Ga., which is still in operation, and in 1914 was reported to have processed about 500 tons of wood per day.1 In 1921 Hercules Powder Co. acquired the Yaryan interests, at which time the production of pine oil was only 3 to 5 million pounds per year and flotation was the largest customer. As time went on, technological advances were made, other companies entered the field, and the production of pine oil increased many fold. The growth of the industry was especially marked during the past 10 years, and in

Jan 1, 1946

By W. T. Bishop

For many years pine oil has been used extensively as a frother for the flotation of minerals, particularly sulphides, yet the published information available to the average user on its composition, chemical and physical properties, has been rather meager. It is the purpose of this paper to discuss these points and their relationship to the frothing properties of pine oil used in flotation processes. Pine oil, as the name implies, is a liquid obtained from the processing of wood of the longleaf and other southern pines. It is a complex mixture of naturally occurring terpene derivatives, primarily alcohols, and a smaller amount of terpenes, which has found many uses in various industries. Its use as a frother in flotation processes was the first large-scale application in industry and today the mining industry still consumes large quantities of pine oil but the textile and disinfectant industries consume comparable volumes. Much is used in soap manufacture and laundry operations. The surface-active properties of pine oil are in a large degree responsible for this versatility. History The name "Naval Stores" goes back to the days when pine tar and pitch were used to caulk leaky ships and 'Oat their ropes and rigging. Today this term is still used to include not only the oleoresinous products of the pine tree—rosin and turpentine— but other products such as pine oil, pine tar, and the many terpene and resinous compounds obtained by extracting the pine wood or tapping the tree. That part of the industry known as "wood naval stores" dates from about the beginning of this century and today produces a large part of the country's rosin and turpentine by processing pine wood. In addition, all of our natural pine oil is supplied by the wood naval stores industry, as tapping of the live tree gives only rosin and turpentine. This latter phase is known as the "gum naval stores " industry. The first successful commercial operation of the steam and solvent process of the wood naval stores in industry was carried out by Yaryan at Cadillac, Mich., in 1909.1 This operation did not prove profitable, so Yaryan went south to utilize the longleaf pine, and built a plant at Gulfport, Miss.2 Soon after, another plant was built at Brunswick, Ga., which is still in operation, and in 1914 was reported to have processed about 500 tons of wood per day.' In 1921 Hercules Powder Co. acquired the Yaryan interests, at which time the production of pine oil was only 3 to 5 million pounds per year and flotation was the largest customer. As time went on, technological advances were made, other companies entered the field, and the production of pine oil increased many fold. The growth of the industry was especially marked during the past 10 years, and in

Jan 1, 1947

PHILIP D. WILSON,* Warren, Ariz. (written discussiont).-Mr. Tovote's idea of attempting to classify according to their broad geologic relations the ore deposits and prospects of the Southwest is an admirable one. Attempts have been made to evolve some comprehensive scheme of classification that would be of practical assistance in determining the possible value of prospects, but the ore deposits are too varied in type, form, genesis, and distribution to lend themselves readily to any definite, scientific pigeon-holing. The classification Mr. Tovote recommends, combining the age of the mineralization with the type of the rock supposed to be its source, is open to criticism even on the evidence he presents. The age of many deposits is not nor can be definitely determined because of the absence of sedimentary rocks in their vicinity. Furthermore, the character of the mineralizing solutions has, in a large majority of cases, no relation to the composition of the associated igneous rock. While the solutions may have originated in the same magma, they were usually a much later manifestation of it, often appearing after the intrusive rock had completely solidified and been subsequently crushed and fractured, and in many cases the chemical difference is very marked. It is true that igneous activity in the Southwest is definitely related to-certain geologic periods. The statement, however, that no ore deposits can unmistakably be referred to periods earlier than late Cretaceous is not supported by fact. The bonanza copper orebodies of the Jerome District are definitely pre-Cambrian. As suggested by J. R. Finlay,1 they are probably post-Beltian or late Algonkian in age, perhaps related to the same great mountain-making period as the copper deposits in the Keweenawan series of Lake Superior and the Sudbury, Porcupine, and Cobalt deposits of Ontario. The proof that they are pre-Paleozoic may be summarized as follows: 1. The pre-Cambrian complex in which they occur is overlaid by a great thickness of Paleozoic sediments with the Tonto or Tapeats sandstone at their base. The only primary mineralization in these sediments is an economically unimportant one connected with very recent basalt. 2. In the United Verde Extension mine, the gossan over the great orebody extends to the old pre-Cambrian surface where it is directly

Jan 2, 1919

By George W. Bain

The good work of the surveys supported by the different branches of the government needs little mention to geologists but is underappreciated by people at large. Geologists and engineers realize their usefulness and yet even from this group one hears occasionally an undercurrent of discontent about their work or the distribution of it. The very fact that discontent arises within and without this group and has drawn attention of legislative bodies of the country in the present time of stress means that a large number of people do not receive or do not realize that they receive benefit from these public works. This seems to be a clear indication that more than the relations between government surveys and the mining industry is involved and that if the mining industry is interested in continuation of the work of these surveys on the past scale they must consider the other survey divisions and their activity. Also, relations between government surveys and certain specialized types of mining have not been as close as they should be. I have been employed in almost the entire range of fields offered to geologists and have studied closely the feeling of people towards geological service. Recently it has been a pleasure to be closely associated with men who were as deeply interested in civic welfare and affairs of state as in the financial success of a large industry developing natural resources. Previously I had seen service in a national survey, a state survey, summer employment by a large mining company exploring new property and detailed geological work for a large corporation. Major responsibility as a college instructor has left me free to view each of these assignments in unprejudiced fashion and at the same time study the relation of government surveys to large natural resource industries, average industrial and construction work and service to nongeologists and laymen. Considerations Governing Geologic Public Service Three groups of people must be satisfied by the surveys if dissatisfaction is to be dispelled. First there is a large group of people who pay taxes to support the government activities and must receive some service

Jan 1, 1935

By George W. Bain

The good work of the surveys supported by the different branches of the government needs little mention to geologists but is underappreciated by people at large. Geologists and engineers realize their usefulness and yet even from this group one hears occasionally an undercurrent of discontent about their work or the distribution of it. The very fact that discontent arises within and without this group and has drawn attention of legislative bodies of the country in the present time of stress means that a large number of people do not receive or do not realize that they receive benefit from these public works. This seems to be a clear indication that more than the relations between government surveys and the mining industry is involved and that if the mining industry is interested in continuation of the work of these surveys on the past scale they must consider the other survey divisions and their activity. Also, relations between government surveys and certain specialized types of mining have not been as close as they should be. I have been employed in almost the entire range of fields offered to geologists and have studied closely the feeling of people towards geological service. Recently it has been a pleasure to be closely associated with men who were as deeply interested in civic welfare and affairs of state as in the financial success of a large industry developing natural resources. Previously I had seen service in a national survey, a state survey, summer employment by a large mining company exploring new property and detailed geological work for a large corporation. Major responsibility as a college instructor has left me free to view each of these assignments in unprejudiced fashion and at the same time study the relation of government surveys to large natural resource industries, average industrial and construction work and service to nongeologists and laymen. Considerations Governing Geologic Public Service Three groups of people must be satisfied by the surveys if dissatisfaction is to be dispelled. First there is a large group of people who pay taxes to support the government activities and must receive some service

Jan 1, 1935

By H. E. Gross

Recently, areas of abnormal rock pressure have been drilled on the Gulf Coast of the United States. These pressures may be caused by the recent and pronounced raising of some of the structures without loss of the formation pressure that existed when the reservoir was developing and the producing sand much more deeply buried. It is possible also that a permeable fissure may connect a shallow accumulation of gas with the gas cap of a much deeper reservoir of oil, gas and water. The pressures are so great that dependence on blowout-prevention equipment alone is hazardous to life and property. Fortunately, wells with excessive casing-head pressures, such as the Stanolind Oates No. 1 of the South Houston field, an 8700-ft. gas well with 6000 Ib. per sq. in., and the near-by Stanolind Candelari No. 1, and 8100-ft. gas well with 5000 Ib. per sq. in., have not blown out and cratered. A case is on record of drill pipe in a well in Harris County, Texas, (Oates No. 1) rotating for 8 hr. through blowout-prevention rams holding a back pressure of 2900 Ib. per sq. in. at the casinghead after the mud was altered by salt-water intrusion. Such conditions warrant the use of extremely heavy muds having low viscosity, made from galena (PbS) or specially prepared mixtures of hematite (Fe²O³) and galena suspended by bentonite. In some Gulf Coast wells, sodium silicate mixed with concentrated brine is used to drill through heaving shale formations. Such a fluid inhibits heaving remarkably, but it is expensive and costs as much as $10 per barrel. Barite has been used to weight this mixture. However, this mineral too rapidly increased an already excessive viscosity and it was thought that galena might be better for weighting such drilling fluid. The operator was anxious to try the latter, but none was available in the district. Laboratory Study of Heavy Muds To foster the use of the plentiful and extremely heavy mineral, galena, research has been done recently at the University of Oklahoma to determine the mud-making properties of this substance. For comparative

Jan 1, 1938

By Guy W. Crane

The geology of the Tintie mining district, fully treated, would occupy an elaborate monograph. This less comprehensive paper is devoted primarily to the occurrence and origin of the orebodies of the district, while space is given to those phases of the general geology only which seem necessary to a proper setting of such a discussion. The first geological report on the Tintic district to be issued was that by Tower and Smith, published in 1899, in the form of a paper in Part III of the Nineteenth Annual Report of the U. S. Geological Survey, and also as Folio No. 65, Geologic Atlas of the United States. About four years ago a second investigation was begun by Waldemar Lindgren and G. F. Loughlin, of the U. S. Geological Survey. With the exception of a paper on the oxidized zinc ores of the Tintic district by Mr. Loughlin, the results of their work are still unpublished. The writer's acquaintance with the district began in the fall of 1913, and has extended over a period of about two years. 1. Location The Tintic district lies about 65 miles due south of Salt Lake City, and on the west central slope of the Tintic Mountains, a short range, which forms the connecting link between the Oquirrh Mountains on the north and the Canyon Range on the south—the group constituting the first of the Basin ranges to the west of the Wasatch Mountains. The productive portion of the district embraces an area about 6 miles long and 2 miles wide, which is divided between Juab and Utah Counties. Within this area are the towns of Eureka, Mammoth, Robinson, Silver City, and Knightsville. All these points are tapped by the Denver & Rio Grande and S. P., L. A. & S. L. Railways. 2. Topography As in most of the Basin ranges, topographic relief is strong, dropping rapidly from peaks of 8,100 ft. above sea level to elevations of 5,600 ft. in Tintic Valley on the west and 4,500 ft. in Goshen Valley on the east.

Jan 1, 1916

By B. L. Landrum, P. B. Crawford

Theoretical and potentiometric model studies have been made of the effect of non-uniform lateral permeabilities on pattern sweep efficiency and production capacity in waterflood and gas-cycling programs. It is shown that a diflerence in directional permeability by a factor of three may result in a sweep efficiency of only 43 per cent for a five-spot pattern or a sweep of either 79 or 38 per cent for a direct line-drive square pattern, depending on the direction of the line-drive flood. Changes in the pattern conductivity varied from about 0.8 to 1.34 over this same permeability variation, depending on the pattern used. It is suggested that measurements be made to determine the possible magnitude and extent of the directional permeability phenomenon early in the field developinent and certainly prior to the initiation of any fluid-injection progmm. INTRODUCTION Irregularities in reservoir sand properties long have been a major difficulty to anyone attempting to explicitly describe the field characteristics of oil production. In particular, it is well known that vertical and lateral permeabilities often differ appreciably; however, the existence of large regions with lateral permeabflity variation is not widely recognized. A number of years ago, extensive studies were conducted by the Secondary Recovery Research Labcratory of the Pennsylvania Grade Crude Oil Association, primarily on the Bradford field. Johnson and Hughes' reported a permeability trend in the northeast-southwest direction. They indicated that flow in the preferred direction may be 25 to 30 per cent greater in that direction than in the northwest-southeast direction. They also reported that similar effects may be found in other nearby fields. The origin of the permeability variation has been discussed by Griffith Hutchinson' described the results of labora- tory tests on limestone cores, pointing out that per-ferential directional permeabilities were significant in one-half of 10 formations studied and that the average permeability ratio was 16:1. Barfield, Jordan and Moore analyzed the fluid-injection displacement performance in the Spraberry and reported that the effective ratio of permeability parallel to the major axis to the permeability perpendicular to this axis was 144:l and that it inclined along an angle of about 30". To prevent the reduction of sweep efficiency which would normally result from flooding or cycling in such reservoirs, well spacing could be varied from the customary square to a diamond-shaped pattern. Johnson and Hughes' presented a method for determining the desired shape. Another method will be discussed in detail in the next section. It is the purpose of this paper to investigate quantitatively the effect of directional permeability upon the sweep efficiency and production capacity of the five-spot and line-drive well patterns. Information currently in the literature will be applied to this particular problem and augmented by a potentiometric model study. It is stressed that the effects herein discussed may or may not be of great importance because field data on this phenomenon are far too scant to form such an opinion. It is suggested that, if conditions similar to those found by Johnson and Hughes frequently exist (as may well be the case), more consideration cdrtainly should be given to this problem.

By A. B. Kinzel

SILICON, unfortunately, is not in the same category as some other metals with respect to the absolute value of the highest purity material prepared. Tucker, in England, and Becket, in this country have devel-oped procedures for the purification of silicon, and Becket's process has made industrially available silicon of a purity of 99.8 per cent or better. However, even the term "silicon metal" may be a paradox to some people, although not more so than the term "amorphous" as applied to silicon. These terms come from commerce, and "metal" is used to distinguish industrially high-purity silicon from ferrosilicon, silicon-aluminum, and other high-silicon alloys. Alloys of iron and silicon with 95 per cent Si or less are known as ferrosilicon, with a designation of silicon content where necessary, and the terns "silicon metal" is invariably applied to the grades containing 96 per cent Si and higher. The Becket method of purification was referred to in a monograph on the Alloys of Iron and Silicon, and the Tucker procedure was described in some detail in that publication.1 In order to get silicon of still higher purity, a sample, prepared by the Becket method, analyzing 99.84 per cent Si, 0.020 Fe, 0.016 Al, 0.005 Ca, 0.025 C, 0.033 per cent 02, 0.006 H2, 0.006 N2, and 0.001 per cent Mn, was crushed to pass a 100-mesh sieve said further purified by a modification of Tucker's procedure. This modification differs from Tucker's method in that after treatment the 100-mesh alloy was centrifuged to remove the last traces of acid. Our directly determined analysis of this purified sample shows: Si, 99.952 per cent; Fe, 0.009; Al, 0.012; Ca, 0.003; C, 0.006; or 99.982 per cent. Silicon by difference equals 99.97 per cent. The variation between silicon by difference and silicon as directly determined is important. Although Tucker mentions the amount of insoluble matter in commercial silicon both before and after his treat-ment, he does not mention the existence of carbon in the alloy; neverthe-less, lie reports silicon by difference. Any final figure as to purity obviously results from agreement between direct determination and

Jan 1, 1939

US 4,194,902 - Pig iron or other molten lion is effectlvely desulfurized by treatment with a mixture preferably about 60% by weight commercial grade calcium carbide, 30% dried limestone diamide, and the remainder bituminous coal. Equivalent desulfurization is obtained using a significantly lesser amount of desulfurizer than in previous mixture of calcium carbide and limestone diamide W Gmohling, assigned to SKW Trostberg AG. Mar 25, 1980. 3 pp. (75-55) Filed: 9-12-78 (941,659) Priority. West Germany, 9-15-77 (2,741,588). Same. British 2,008,153, dated May 31, 1979.

Jan 1, 1982

By Elmer R. Kaiser

Cooperative research is an established and important activity of modern business by which whole industries can advance on a broad front. The economy of jointly sponsored research as well as the limited research talent available direct attention to the advisability of projects in which a number of companies participate. After outlining the growth of industrial research, the paper discusses one successful method for organizing and financing group research programs. A systematic procedure is advocated by which engineers and scientists can bring to management practical plans for cooperative research and development programs.

Jan 3, 1950

By W. F. Kieschnick, and W. J. McGuire&apos, Eugene Harrison

This paper concerns the induction and extension of fractures into rock formations as involved in drilling, completing, and production stimulating operations on wells. Conclusions concerning formation breakdown are derived from (I) a review and extension of published analyses relating to mechanical theories of rock stress and the state of stress in the earth's crust and (2) a correlation of field data from fracturing operations. Conclusions concerning the mechanics of fracture extension, which indicate the relationship between fracture dimensions and rock properties, depth, and volume of injected fluid, are tentative and largely establish limits of relationships. These conclusions are derived from stress calculations, limited field data, and laboratory experimental studies. The experimental work involves the study of the stresses at the fracture boundaries and the geometry of pressurized fractures by means of photo-elastic modeling methods. Results of this investigation indicate that a large majority of pressure induced wellbore fractures are vertical, particularly in deeper wells; and variations in the pressures necessary to create and extend fractures can be explained largely on a basis of established rock properties. It is also shown that variations due to tectonic forces should usually be expected to be slight. Other results indicate that during that extension of fractures rather large fracture volumes are temporarily created by the parting of the formation. The purpose of this paper is to present the results of calculations and laboratory experiments concerning the mechanics of fracture induction and extension with a view to broadening existing knowledge relating to these phenomena. It is believed that continued progress in developing knowledge of this type is important to the further development of techniques for drilling and completing wells. When a wellbore is subjected to sufficiently high pressure, fracturing of the formation surrounding the well occurs. This phenomenon is a common cause of lost circulation during drilling operations, is a deliberately planned factor in most squeeze cementing operations, and is the controlling factor in many productivity stimulation operations. The exploitation of formation fracturing in recent years has been particularly impressive in sand-viscous fluid well stimulation treatments which were first introduced to the industry by the Stanolind research group1,2,3 several years ago. The borehole fracturing phenomenon has been analyzed mathematically by application of the principles defining the elastic and inelastic behavior of thick-walled cylinders of homogeneous, isotropic, and impermeable material.1,5,6 This basic argument is re-presented in this paper along with new considerations which strengthen it. In addition to these arguments relating to fracture induction some calculations and experimental results relating to the mechanics of fracture extension are presented. Since the nature of the pressure induced fracture at distances from the well is of great importance in considerations of well stimulation procedures there appears to be a need for an integrated approach which deals with the mechanics of fracture extension as well as with wellbore rupture.

Jan 1, 1955

By Blamey Stevens

The object of this paper is to show how igneous intrusion is governed by definite mechanical laws. A distinction is made between dikes and fissures, and the various characteristics of intrusions are explained on an exact scientific basis. The modification of rock-stresses by intrusion is then considered and extensive isostress regions are recognized. Finally, a complete classification of intrusions is constructed covering all possible cases. The generalizations of observed data, taken from Geikie's Text-Book of Geology, confornl to the laws of intrusion herein stated, and the deductions based upon these lams. No authority, however, is quoted for the type which I hare named a corrugated intrusion. Its existence is a necessary deduction from the laws of intrusion, and even the entire absence of examples in technical publications cannot disprove its reality. In all probability, corrugated fissures would have remained undiscovered, but for the nrorking of mineral veins. As intrusions of tabular form are seldom worked for commercial purposes, it has been left for theory to anticipate the discovery of corrugated dikes. In the light of these laws of intrusion and the corresponding laws of fissures,' there seems to be a remarkable uniformity of stress-distribution in rocks at moderate depths. This renders possible the mathematical calculation which should help us to approximate exact science in this and kindred branches of applied geology.

Jan 1, 1911

Discussion of the paper of L. C. Graton and Joseph Murdoch, presented at the New York Meeting, February, 1913, and printed in Bulletin No. 77, May, 1913, pp. 741 to 797. THOMAS T. READ, New York, N. Y. (communication to the Secretary *) :-At the meetings of English technical societies it not infrequently happens that, during the discussion of a paper, someone will arise to say that although he highly appreciated the material presented, nevertheless he believed it would have been better if some other phase of the question had been more highly emphasized. Assuming that this form of discussion is permissible in the Institute, I should like to reiterate the point made by Prof. A. J. Moses that conclusive proof of the identity of the minerals in question is an essential feature of the study of ores in this way. This is also expressed by Paul Krusch in his recent valuable paper 1 on the sulphide ores (in which he arrives at conclusions diametrically opposed to those of Mr. Graton), as follows : ?The diagnostic properties of the various ore minerals are known to but a limited circle of investigators." Many earlier investigators began the study of ores beneath the microscope by reflected light, but discontinued their work, in most cases, because they were unwilling to undertake the great amount of preliminary work necessary to securely establish a basis for their inferences. It is evident that Messrs. Graton and Murdoch realize that the promised later paper on diagnostic characters will be the more important of the two, but the point should be emphasized to forestall a flood of literature from other investigators who may gain the impression that the brief survey of polished specimens is a wade mecum to incontrovertible conclusions as to any given ore deposit.

Jan 10, 1913

By I. N. Knapp

Foreword I HEREWITH present some notes on the use of Portland cement to cement in the casing, and for plugging, to exclude water from oil and gas wells, and the methods employed. I have used my best efforts to make each step of the operation of cementing wells perfectly clear. The information is the result of actual experience and observation. The illustrations are from original drawings made especially for this paper. Portland Cement It is not necessary to discuss here the manufacture of cement. Any established brand of the slower setting Portland cements may be purchased with the confidence that it will harden, if properly used, and exclude water from and plug wells efficiently. Setting.-By the setting of cement is meant its initial change from a soft or plastic mortar to a friable solid. After the cement has become thoroughly set it is still very weak and can be readily pulverized in the fingers. Setting is thought to be effected by the crystallizing out of the silicate and the aluminate of lime, which are soluble in water in their anhydrous form. After dissolving in the water they pass to the hydrated state, in which they are insoluble, and hence are precipitated in a crystalline form.

Jan 3, 1914

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 baits 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 Junc-tion, Philadelphia, Pa. The "cornerstone" of the Baltimore & Ohio Railroad was laid Apr. 4, 1828, and the first 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 he identified with American locomotives until locomotives are forgotten. The Wheels on these first locomotives, designed to run on this primitive rail, were 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 follies, or rings. 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.

Jan 1, 1917

By Carl Zapffe

Because no rock outcrops exist in the Cuyuna district, it is necessary first to make a magnetic survey with a dip needle, or possibly with a sun-dial compass, and determine the area or belt of magnetic variations and the maximum lines of magnetic attraction. A dip-needle survey is quicker to make, is sufficiently accurate, and will suffice. Regardless of how poorly defined the magnetic attractions may be, it is important that they be determined. Even if drilling has developed ore on an adjoining property, the survey should not be omitted. Iron-bearing formation is indicated by the magnetic attractions, but whether or not ore exists must be determined by drilling. The maximum line of magnetic attraction offers the best place to begin drilling. If no magnetic attraction exists, nearby developments are the only guide; and if these also are lacking, drilling is governed by guess. Test-pitting is not employed in exploratory work because the surface is too deep. Tunneling cannot be used because the topography is not suitable. Exploration shafts are a waste of time and expense, because from every standpoint drilling with churn and diamond drills is the most applicable method for exploratory work. Light drilling equipment only is needed. Rarely have heavier drills been required, for seldom do holes exceed 400 ft. in depth, and about 100 ft. of this is in glacial drift which is easy to penetrate. The deepest hole is 1023 ft. Because of the steep inclination of the strata and the narrowness of the orebodies, many angle holes have been drilled, mostly at 60' to 70" from the horizontal and against the dip of the formation. Angle holes are most advisable. If after initial drilling the beds are of shallow dip, vertical holes or holes of any angle can be used. The total cost of drilling a property is much greater if only vertical holes are used because more holes must be drilled to obtain the requisite information than when angle holes are used. Many tests for variation in angularity of a finished hole have seldom shown more than 2'; therefore, such tests may with safety be abandoned. Because the orebodies are generally about 100 ft. wide and cross a 40-acre tract at a slight angle, and as the dips are usually about 70"

Jan 1, 1925

To the members of the A. I. M. E., who have given much and risked all to fight "Over There" with pick, or gun, or brain, and to the members who have chosen the sometimes more self-denying duty of remaining at home to help produce metals for fighters: Your experience in foreign lands has bred in you that spirit of internationalism which will soon be infused into every corner of our country by virile lads thrilling from a great experience in an old, yet new, land over the seas. To them the East will not seem as far from the West as it was, nor the North from the South. Sectional jealousies will seen despicable to one who has fought for a great ideal shoulder to shoulder with real men of other nations. And they who have willingly sacrificed much on the altar of service will have little patience with an egotist, be he laborer, tradesman, capitalist or engineer. The problems which peace brings to us are more difficult than those of war and their solution requires not only cool heads, tolerance, and wise judgment, but the "getting together" of sections and classes and individuals. The triumph of justice over individualism, represented by the draft law, must be repeated, for there are "slackers" in peace Is well as in war, and the spirit of self-denial expressed in response to Liberty Loans, Red Cross, and Welfare drives and Food Administration appeals must live. We have only just begun to learn how to serve. It is often claimed by our members that the engineer is not given, in the community at large, the recognition which his training should merit; that his reward is not as great nor his service as welcome as it should be. Public service is generally assumed to be a logical activity for a lawyer,

Jan 12, 1918

By S. A. Mersol, C. T. Lynch, F. W. Vahldiek

The room-temperature Knoop hardness of single -crystal titanium diboride has been determined. Variations in microhardness have been correlated with orientation and structural imperfections in the crystals. Maximum differences in hardness values of 750 kg per sq mm with respect to orientation and 450 kg per sq mm with respect to substructure were found. The effects of etchants, load on indenter, and degvee of cracking of indentation were studied. The average hardness was determined as 2800 kg per sq mm on the as-grown crystals. Annealing increased the average hardness to 3375 kg per sq mm. ThE microhardness of polycrystalline titanium diboride approximating the stoichiometric composition TiB, has been studied by several investigators. The values for the Knoop hardness number range from 2710 kg per sq mm (Khn = 2710 kg per sq mm) to 3400 kg per sq mm.'-4 Samsonov et al.' reported a Vickers hardness number of 3400 kg per sq mm (Vhn = 3400 kg per sq mm) at 120-g loads for a 98 pct Ti + B material of 96 pct theoretical density. Recently Dunegan measured the Vickers hardness and obtained 2060 kg per sq mm with a 10-g load (Vhnlo = 2060 kg per sq mm), 1425 kg per sq mm for Vhnloo, and 1320 kg per sq mm for Vhnlooo. We have obtained a Khnloo = 3000 * 350 kg per sq mm for hot-pressed polycrystalline TiB2 that was 99.1 pct Ti + B and 96.6 pct of theoretical density. The present investigation has been made on single-crystal titanium diboride boules, and is believed to be the first such study on TiB, crystals of known orientation. EXPERIMENTAL The single crystals were prepared by a Verneuil-type process using an electric arc by the Linde Division of Union Carbide Corp. The largest specimens were 6 mm in diameter by 12 mm long. The crystals were of theoretical density (4.50 g per cm3) with a Ti + B content of 99.8 pct. The major impurities present were: 0.03 pct (by weight) 0, 0.06 pct C, 0.01 pct Si, 0.05 pct Fe, 0.01 pct Cr, and 0.01 pct Ni. The crystals were boron-rich, the average boron content being 31.S7 wt pct (stoichiometric value is 31.12 wt pct), and titanium-poor, the average titanium content being 68.2 wt pct (stoichiometric value is 68.88 wt pct). Titanium was determined gravimetrically by cupferron precipitation and boron by titration of H3B03 from a NaOH-fused specimen after removal of titanium with BaC03. The outer edge of the boule accounted for some of the excess boron. An electron-microprobe analysis showed that the titanium content increased from 60.0 wt pct at the edge to 68.5 wt pct at D, ~ 1000 p, where D, = distance from outer edge (see Fig. 5). X-ray measurements indicate that the boules are single crystals with considerable substructure. Upon etching this structure is seen in the form of a Widmanstatten-type rhombohedral line pattern in the basal (c) plane and a parallel "lines" pattern in the prism (a) planes. A typical WidmanstHtten-type pattern is seen in in Fig. 1. Electron microscopy reveals that the lines are less than 1 p across, which does not allow direct electron probe or microfocus X-ray determination of their composition. The identity of the second phase has not been established. It might be a higher boride or a nonstoichiometric TiB2. On annealing above 2200°C the precipitate is dispersed and dissolves in the matrix. The best etchants found were HF/HNO/HO, KF(CN)$NOH/HO (Murakami's Etch), and A large number of other etchants were previously Studied. The acidic etchant produced an acicular or "needles" pattern in the (a) planes which is an etchant effect on the "lines" pattern.

Jan 1, 1965

By John Rogers

The goal of a detailed quantitative understanding of the variables insulfide flotation in terms of established, or new, scientific principles is still distant, although there has been a good beginning in the past 50 years with more rapid progress since 1930. Advances have paralleled closely those in other branches of surface chemistry and the development of a series of experimental techniques such as contact angle, surface area measurement, radioactive tracers, infrared spectra, electron diffraction, monolayer, and electro- chemical methods of investigation. The second editions of books by Sutherland and Warkl ( 1955) and Gaudin2 ( 19571, are detailed accounts of this progress. The complexity of sulfide mineral flotation systems is indicated by Sutherland and Warkl who list 32 variables of flotation, of which only 22 can usually be controlled by the metallurgist. A consequence of this multiplicity of variables, many of which may be specific to each particular ore, is that ways of floating sulfide minerals from new ores are still developed empirically. How- ever, this review will try to show how the chemistry of the function of frothers, collectors, depressants, and activators in sulfide flotation is being steadily unravelled. Chiefly, it will be concerned with the interaction of pure soluble compounds with individual sulfide minerals, the surfaces of which are often not stoichiometric for several reasons discussed by Plaksin.3 As a result, for example, a freshly cleaved galena surface has cathodic and anodic areas which have different degrees of oxidation and different reactivity to- wards collectors like xanthate. Such complicating considerations should be remembered in the subsequent discussion of pure minerals. THE NEED FOR FLOTATION REAGENTS After considerable controversy it has been established with a few exceptions that unoxidized, uncontaminated sulfides will not float. Moreover all flotation plants recovering sulfide minerals use collectors which are removed from the circuit with the sulfides. Gaudin, Miaw, and Spedden4 have discussed the relation between the crystal structure of solids and the native floatability of the exceptions mentioned above. A second question which has been much explored is the nature of the surface on which a collector like xanthate is adsorbed or reacts. Is this the un- changed surface of the sulfide mineral, or does the adsorption depend on the initial oxidation of the sulfide surface ? Sutherland and Warkl and Gaudin2 discuss the work of Taggart5 and others on this question without reaching any other conclusion than that oxygen was important.

Jan 1, 1962