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By Whitman E. Brown

The installation in 1948 of a Humphrey spiral concentrator section at the Hill-Trumbull plant of The Cleveland-Cliffs Iron Co. is the latest commercial method on the Mesabi Range being used for the recovery of fine iron ore. In two stages of concentration 84 spirals treat approximately 120 long tons per hour of minus 1/8 in. ore. These spirals augment the production of the heavy-density plant which recovers the plus 44 in. iron from the plant crude ore. Structure of the ore is such that, when crushed, about 50 pct of the plant crude is minus 1/8 in. size. After desliming in a 66 in. Akins classifier, grinding the classifier product in a ball mill and again desliming in a 78 in. Akins classifier about 15 pct of the crude ore remains to be treated in the spiral plant.

Jan 1, 1949

By L. de Florez

The successful control of any operation, whether industrial, military, or purely physical, is fundamentally dependent upon the same elements: (I) The securing of accurate and pertinent information concerning the factors involved in the operation; (2) Correct interpretation of their relationship as affecting future results; (3) Efficient means for effecting changes in the factors governing the operation to shape the result. The analogy which exists in the control of operations in these widely differing fields of action is of utmost interest, and in considering the physical control of a process, the realization of its existence permits a clearer conception of the steps required to achieve results and aids in formulating the problems to be met. Let us imagine, for instance, the requirements for successfully conducting a business. It is evident that the first requisite lies in obtaining continuous and reliable information concerning the functioning of its various branches and in detecting, with the least possible delay, any tendency of change in their functions; next, in correctly analyzing this information by comparison with past records, showing the relation of the particular business to general conditions in the trade; and finally, in employing means for counteracting any unfavorable change in general conditions, or compensating for its effects by an appropriate action. Likewise, in military operations, the success in carrying out a plan lies primarily in the maintenance of proper intelligence and communication service, which furnishes information as to the disposition of forces; in correct analysis of the ascertained position, guided by fundamental knowledge of tactics; and finally, on the efficient carrying out of orders and effecting corrective movements. In the physical operation of a process, such as for example in cracking, our information is obtained by pressure and temperature instruments, etc., which permit us to visualize existing conditions under which the operation is being carried out. The information at hand is then analyzed and certain conclusions arrived at as to the results which will be obtained under the observed conditions. If this analysis should indicate, in the

Jan 1, 1928

By W. S. Weeks

In coursing the ventilating air through a mine it is often necessary to restrict a comparatively open split in order that it may carry exactly the desired quantity of air. Such a restriction is known as a regulator, and usually takes the form of a partition with a hole in it. The quantity of air circulating is controlled by the size of the hole or orifice. For example, it is desired to force a quantity q I cu. ft, per min. through split a (Fig. 1) and the quantity q2 through split b. It requires a pressure of 2 in. water to force the desired quantity through a, and a pressure of 1 in. to force the desired amount through b. The pressure drop between points A and B must be 2 in and a pressure of 1 in. must be destroyed in split b. This is done by inserting a regulator in b, which causes the velocity to increase in the orifice and results in a change from pressure-head to velocity-head. If the air, after passing the orifice, is slowed down in a turbulent manner, all of the velocity-head does not change back into pressure-head, so a permanent loss of static pressure results. A classic formula for computing the area of an orifice to destroy a certain amount of static pressure has been handed down from early days: 0.0004Q a =2 This formula is based on the assumption that all velocity-head in the orifice is "destroyed;" that is, does not reappear again as either velocity-pressure or static pressure. The derivation of the formula is as follows: h = head lost in regulator in fect of air. v = velocity in regulator in fect per second. q = quantity circulating in cubic feet per second. Q = quantity circulating in cubic feet pcr minute. a = area of orifice in square feet.

Jan 1, 1928

Coal was known in this county before 1819, but there is no record of its use before that year. In that year a furnace, the first one built in the northwestern countries, was put in blast on Bear Creek; it was built to use coke and its first blast was with this fuel, which was made in heaps, but the blast was too weak and the furnace chilled after two or three tons of iron had been made. Charcoal was then substituted, and this use of coal ceased.1 In November of the same year a resolution was adopted urging state aid for a road from Kittanning to. Hamilton, New York: "that this road will increase the trade and industry of the whole county, between Pittsburgh and the New York line; and that our soil will in consequence be better tilled, our mines of coal, of iron and of salt, be better wrought, etc."2 In 1828 an advertisement of lands situated near Freeport on the Allegheny River and contiguous to the canal nearly completed between the Kiskiminitas and Pittsburgh stated that they contained "large and never failing springs, Coal in abundance, and a great deal of Fine Timber."3 In 1830 there were said to have been 24 salt wells in this county producing 327,000 bushels of salt, chiefly on the Kiski and Allegheny Rivers. In 1837 there were a number of wells in the vicinity of Freeport. As all the salt works on the Conemaugh River, were using coal long before 1830,4 it is safe to say that a considerable tonnage of coal was used for some years in these plants. In 1837 a tract of land in Clarion Township having a new saw mill and abounding "in Stone Coal" was offered for sale,5 and also one in Toby Township having "an abundance of the best quality of iron ore and stone coal."' In 1839 an advertisement in the Pittsburgh Mercury said

Jan 1, 1942

By W. H. Emmons

Many mineral veins occupy faults, and movements on certain warped fault planes have resulted in openings. On normal faults the steeper parts have the widest openings, and on reverse faults the flatter parts have the widest openings. Theoretically the width of the opening is the sine of the angle of deflection times the amount of movement on the fault plane, but actually the widths of some of the openings are probably less because of readjustments of walls along joints or of other readjustments. The first treatment of the subject seems to have been in a book on mineral veins by John Leithart, published in Newcastle, England, in 1838. Later the subject was treated in various texts published in Germany, in England, and elsewhere. The subject was not given much prominence in the earlier American literature on economic geology, but has interested several workers in that field in the past decade. In this paper examples of districts showing ore shoots on warped faults, with relations noted, are described. Fault veins of the three depth classes of veins are noted. Many epithermal veins are in normal faults, and commonly the larger ore shoots are in their steeper portions. Many mesothermal veins are in reverse faults and, many others are in normal faults. The flatter parts of veins in reverse faults are commonly wider than the steeper parts, although they are not always as rich as the steeper segments of the veins. There are not many hypothermal veins in faults of measured displacement. Introduction When faults are followed along dip or strike, many of them are found to have curving or warped surfaces, and cross sections through them in most directions show sinuous or waving intersections. Openings are formed where one wall moves away from the other (Figs. I,2). Where there is a bend in the fault, movement in any directions except along the axis of the bend will

Jan 1, 1949

By W. H. Emmons

Many mineral veins occupy faults, and movements on certain warped fault planes have resulted in openings. On normal faults the steeper parts have the widest openings, and on reverse faults the flatter parts have the widest openings. Theoretically the width of the opening is the sine of the angle of deflection times the amount of movement on the fault plane, but actually the widths of some of the openings are probably less because of readjustments of walls along joints or of other readjustments. The first treatment of the subject seems to have been in a book on mineral veins by John Leithart, published in Newcastle, England, in 1838. Later the subject was treated in various texts published in Germany, in England, and elsewhere. The subject was not given much prominence in the earlier American literature on economic geology, but has interested several workers in that field in the past decade. In this paper examples of districts showing ore shoots on warped faults, with relations noted, are described. Fault veins of the three depth classes of veins are noted. Many epithermal veins are in normal faults, and commonly the larger ore shoots are in their steeper portions. Many mesothermal veins are in reverse faults and, many others are in normal faults. The flatter parts of veins in reverse faults are commonly wider than the steeper parts, although they are not always as rich as the steeper segments of the veins. There are not many hypothermal veins in faults of measured displacement. Introduction When faults are followed along dip or strike, many of them are found to have curving or warped surfaces, and cross sections through them in most directions show sinuous or waving intersections. Openings are formed where one wall moves away from the other (Figs. I,2). Where there is a bend in the fault, movement in any directions except along the axis of the bend will

Jan 1, 1949

By L. G. Huntley

I. HISTORY OF OIL DEVELOPMENT IN MEXICO THE occurrence of oil or "tar" in Mexico was mentioned as early as the seventeenth century by Friar Sagahun, who gives the Indian name "chapopote," by which these asphalt seepages are still called. This asphalt was apparently used, as it has been used by primitive people in many parts of the world, in religious ceremonies and for medicinal purposes. Travellers also report that the ruins in Yucatan and the pyramids in southern Mexico show traces of the use of "chapopote" as a building cement.1 DeGolyer says that the first attempt to exploit oil or gas in Mexico in a commercial way is shown by the records of the Memoria de Fomento of 1865, when permission was granted to a Senor Ildefonso Lopez to exploit the deposits of petroliferous substances in the San Jose de Ias Rusias area in the State of Tamaulipas. Other concessions follow, and probably refer to surface seepages which occur in that district. This was several years after the discovery of oil in Pennsylvania. In 1868, a well 125 ft. deep was drilled by a company organized in Mexico City, in what is now known as the Furbero district, and a little oil was refined there. In 1873, residents of Tampico denounced seepages along the Tamesi River, and asphalt was mined near Tempoal in the Canton of Tantoyuca. No drilling was attempted. But between 1880 and 1883 several shallow wells were drilled for oil in Mexico, two of them being near the present Potrero de Llano field west of Tuxpam. The wells were drilled by a Boston company with Canadian rigs, and are said too have reached a depth of about 400 ft., while one is reported to have flowed. Several other abortive attempts were made to drill for oil between 1885 and the beginning of the present century, about which time the Mexican, Petroleum & Liquid Fuel Co., Ltd., in which Cecil Rhodes was interested drilled 24 wells unsuccessfully, several of them as deep as 1,500 ft., in the State -

Jan 9, 1915

By R. I. Williams

Kennecott Copper's mining activities in Arizona are conducted by the Ray Mines Div., located in Ray, Ariz., in the Mineral Creek mining district about 60 miles southeast of Phoenix. The Ray orebody lies in a mineralized zone belted on the east, west, and north by well defined faults. The orebody consists principally of schist with intrusions of quartz porphyry and diabase. The dominant ore mineral in the schist and quartz porphyry is chalcocite, with some native copper, and in most areas the orebody has been heavily oxidized. In the diabase the dominant ore mineral is chalcopyrite. Ore deposition in the schist portion is very erratic, with no apparent structural explanation. In 1873 silver prospectors opened the mining district, but it was not until 1899 that an English company made the first major attempt to exploit the copper deposits. This venture failed because of improper sampling and limited development work. In 1904 D. C. Jackling, Seeley Mudd, and Philip Weiseman became interested in the Ray Copper Co. and the Gila Copper Co., which later merged as Ray Consolidated Copper Co. In 1926 the Nevada Consolidated Copper Co. took over Ray Consolidated and in turn was taken over by Kennecott Copper Corp. in 1933. The extensive program of surface and underground development and exploration begun in 1907 continued through successive changes of management and ownership to the present time.

Dec 1, 1956

By Stanley J. LeFond, Langtry E. Lynd

Elemental titanium has become famous as a space age metal, because of its high strength/ weight ratio and resistance to corrosion. However, the major use is in the form of titanium dioxide pigment, which because of its whiteness, high refractive index, and resulting light-scattering ability, is unequaled for whitening paints, paper, rubber, plastics, and other materials. A relatively minor use is in welding rod coatings, in the form of the mineral rutile. United States consumption of titanium dioxide in concentrates for these applications in 1982 was as follows: pigments, 630,000 st; titanium metal, 31,000 st; and welding rod coatings, 5,000 st. The only commercially important titanium ore minerals at the present time are ilmenite and its alteration products, and rutile. Titanium was discovered by Gregor in 1790, as a white oxide which he recovered from menaccanite, a variety of ilmenite occurring as a black sand near Falmouth, Cornwall. Barksdale (1966) stated that the fundamental chemical reactions on which the present day titanium industry is based were known before 1800, although it was not until 1918 that these pigments were available commercially on the American market. Pings (1972) outlined the early history of the titanium industry in the United States, referring to the work of Guise (1964) and others: Mining of titanium minerals in the United States began sometime between 1880 and 1900, in Chester County, Pennsylvania. Small quantities of rutile were also produced during that time in North Carolina and Georgia. In 1901 rutile was mined from a deposit near Roseland, VA, and was used in making titanium chemicals and for coloring ceramics. Ilmenite in the deposit was produced as a separate item in 1913, and rutile and ilmenite were obtained from this deposit through 1921. The mining of titanium bearing beach sands began in 1916 near Mineral City and Pablo Beach, FL, for the purpose of making titanium tetrachloride to be used in tracer bullets, flares, and smokescreens. The titanium pigment industry was founded in 1918. By 1928 a large part of the domestic production of rutile, ilmenite, and zircon came from Florida. However production ceased in 1929 in Florida with the mining of newly discovered deposits in Virginia which were mined until 1968. The discovery of new deposits in Florida, and the development of better mining and concentrating methods for low-grade sands, led to a return of activities in this area. The large deposits near Tahawus, NY. were brought into production in 1942 by National Lead Co. (now NL Industries, Inc.), and by 1949 this company was the leading producer of ilmenite in the world. In 1948 the extensive deposits of ilmenite and ilmenite-bearing iron ores were discovered in eastern Quebec. The large Trail Ridge sand deposit in Florida was discovered by E. I. du Pont de Nemours & Co., Inc. geologists in cooperation with the US

Jan 1, 1983

By C. V. Corless

WE are living at a period of the world's history in which social phenomena are on so vast a scale, are of so profoundly soul-searching a nature, and are occurring in such rapid succession in the great world drama in which we are both actors and spectators, that, in our efforts to obtain a rational point of view in relation to them, our minds may fail to discern the simple in the complex and our understanding is liable to be-come confused or even overwhelmed. To the social student whose scientific training has convinced him of the truth of the evolutionary law, Natura non facit saltum, it is neither the vast scale of the events; their deeply soul-stirring nature, nor their rapid succession that matters so much, as the discovery of the underlying principle or law in accordance with which the disintegration and reintegration, which are the two aspects of social evolution, or indeed of evolution everywhere, are occurring. He is most deeply concerned in seeking an answer to the question: Have we in the present great and perplexing upheavals in human society, whether regarded in Central Europe, in Russia, in Great Britain, or in America, a really new cause at work, or, have we, though on a very- large scale, merely new manifestations of the working out of an old principle? When we think of the appalling struggle in Europe, into which the world's greatest exemplar of democracy was finally drawn, no one has any hesitation in admitting that the great conflict was fundamentally a life-and-death struggle for self-preservation and self-propagation on the part of autocracy. The variations we meet with in the statement of the cause of the war arise mainly from differing distances of perspective: but in the last analysis all agree that the autocratic system of political government, which found its very soul and center in Prussian despotism, was consciously arrayed in a final "world-power-or-downfall" struggle against a love of freedom which was steadily widening and-deepening throughout the world, and particularly throughout those parts of the world where this love of freedom and justice has found expression in democratic institutions. It is not irrelevant to our discussion to recall in passing that this most imposing structure ever conceived by the human mind as an instrument of tyranny is lying today an irretrievable mass of ruins, completely over-

Jan 4, 1919

By G. Sachs, S. I. Liu

INTRODUCTION IN a previous investigation on the effects of repeated strains of large magnitude on the aluminum alloy 24ST, it was found that the reduction in ductility by straining in tension was partially restored by a subsequent compression.&apos; As illustrated by the dashed line in, Fig I,§ the ductility (EF) retained after prestraining in tension by a certain amount (EI) and measured in a subsequent tension test is represented by a straight line sloping down under 45°. If a compression of the same magnitude as the first tension is inserted (E2 - EI) between prestraining and final testing in tension, such a "balanced" tension-compression cycle yields a ductility considerably higher than that present after prestraining in tension only. . The results of these tests can be correlated with those of an investigation on the effects of prestraining in compression.2 As also shown in Fig I, the ductility in subsequent tensile tests decreased with compression, at a rate considerably slower than that after prestraining in tension. The above discussed testing conditions can be considered as special cases of a general straining cycle, consisting of first, straining in tension by an amount E1, subsequently straining in compression by an amount E2, and finally determining the retained ductility, Ef, in a tensile test. Prestraining in tension is then represented by E1 > o and E2 = o. Prestraining in compression is given by E1 = o and e2 < o. Balanced cyclic straining is defined. by the condition E1 > o and E2 = -El. In order to obtain further information on the effects of straining cycles consisting of tension and subsequent compression, further tests were made, varying both the tension strain, E1, and the compression strain, E2, within extreme limits; El varied between 0.06 and 0.28 and E2 between -0.008 and -0.60 approximately. Apparently, such tests have not been previously performed. They revealed phenomena which have not been recognized to date. The results of the investigation are herewith reported, without attempting to correlate them with internal processes within the metal structure. However, in order to assist in an analysis of this type, the results have been represented in various manners. In addition, further test data on the effects of prestraining by compression were provided by using specimens of various contours (notched specimens) in the subsequent tensile tests.

Jan 1, 1948

By G. Sachs, S. I. Liu

Introduction In a previous investigation on the effects of repeated strains of large magnitude on the aluminum alloy 24 ST, it was found that the reduction in ductility by straining in tension was partially restored by a subsequent compression.&apos; As illustrated by the dashed line in Fig I,$ the ductility (e~) retained after prestraining in tension by a certain amount (el) and measured in a subsequent tension test is represented by a straight line sloping down under 4s°. If a compression of the same magnitude as the first tension is inserted (€2 = — €1) between prestraining and final testing in tension, such a "balanced" tension-compression cycle yields a ductility considerably higher than that present after prestraining in tension only. The results of these tests can be correlated with those of an investigation on the effects of prestraining in compression.~ As also shown in Fig I, the ductility in subsequent tensile tests decreased with com- pression, at a rate considerably slower than that after prestraining in tension. The above discussed testing conditions can be considered as special cases of a general straining cycle, consisting of first, straining in tension by an amount el, subsequently straining in compression by an amount e2, and finally determining the retained &apos;ductility, e,, in a tensile test. Prestraining in tension is then represented by el > o and e2 = o. Prestraining in compression is given by e~ = o and e~ < o. Balanced cyclic straining is defined by the condition el > o and cz = — 61. In order to obtain further information on the effects of straining cycles consisting of tension and subsequent compression, further tests were made, varying both the tension strain, el, and the compression strain, e2, within extreme limits; el varied between 0.06 and 0.28 and e2 between — 0.008 and —0.h approximately. Apparently, such tests have not been previously performed. They revealed phenomena which have not been recognized to date, The results of the investigation are herewith reported, without attempting to correlate them with internal processes within the metal structure. However, in order to assist in an analysis of this type, the results have been represented in various manners. In addition, further test data on the effects of prestraining by compression were provided by using specimens of various contours (notched specimens) in the sub-

Jan 1, 1949

By J. H. Nead, T. S. Washburn

The grades of commercial steel produced in large quantities can be divided into two general types from the standpoint of ingot structure— killed and rimmed. Killed steel covers a wide variety with carbon contents throughout the range of the steel portion of the iron-carbon diagram, and is the kind usually used in the production of alloy steels. Rimmed steel is normally associated with carbon ranges under 0.30 per cent, and is not yet used to a large extent in alloy practice, except for copper-bearing steels. The fundamental differences in the ingots made from these two types of steel can be seen most easily in Figs. 1 to 7. In the rimmed ingot shown in Figs. 5 to 7 there are two lines of blowholes approximately parallel to the sides and coming together at the top and at the bottom of the ingot. In the killed ingots shown in Figs. 1 to 4 these blowholes arc not present. Also, the rimmed ingot has no well defined pipe, as compared to the deep pipe on the killed ingots, and there are numerous primary blowholes in the lower portion of the rimmed ingot perpendicular to the surface and close to it, while on the killed ingot there are no blowholes of this type in the ingot shown in Fig. 1 and very small ones close to the surface in the lower part of the ingot shown in Figs. 2 to 4. With respect to the presence of pipe and the primary blowholes, the structure may vary considerably in both rimmed and killed ingots, therefore these cannot be considered as fundamental structural characteristics differentiating the two types of steel. The primary blowholes in rimmed ingots may be much less pronounced than those in the ingot shown in Figs. 5 to 7—as, for example, in "ingot iron," which is entirely free from them. An example of a cross section of an ingot-iron ingot is shown on page 16 of "Research and Methods of Analysis of Iron and Steel," published by the American Rolling Mill Co. (1920). A certain amount of pipe may also occur in rimmed ingots, though it is normally porous and not as well defined [or deep as in the killed ingot of Fig. 1. In killed ingots, primary blowholes may occur near the surface, as in Figs. 2 to 4, and

Jan 1, 1937

By T. S. Washburn

THE grades of commercial steel produced in large quantities can be divided into two general types from the standpoint of ingot structure-killed and rimmed. Killed steel covers a wide variety with carbon contents throughout the range of the steel portion of the iron-carbon diagram, and is the kind usually used in the production of alloy steels. Rimmed steel is normally associated with carbon ranges under 0.30 per cent, and is not yet used to a large extent in alloy practice, except for copper-bearing steels. The fundamental differences in the ingots made from these two types of steel can be seen most easily in Figs. 1 to 7. In the rimmed ingot shown in Figs. 5 to 7 there are two lines of blowholes approximately parallel to the sides and coming together at the top and at the bottom of the ingot. In the killed ingots shown in Figs. 1 to 4 these blowholes are not present. Also, the rimmed ingot has no well defined pipe, as com-pared to the deep pipe on the killed ingots, and there are numerous pri-mary blowholes in the lower portion of the rimmed ingot perpendicular to the surface and close to it, while on the killed ingot there are no blowholes of this type in the ingot shown in Fig. 1 and very small ones close to the surface in the lower part of the ingot shown in Figs. 2 to 4. With respect to the presence of pipe and the primary blowholes, the structure may vary considerably in both rimmed and killed ingots, therefore these cannot be considered as fundamental structural characteristics differ-entiating the two types of steel. The primary blowholes in rimmed ingots may be much less pronounced than those in the ingot shown in Figs. 5 to 7-as, for example, in "ingot iron," which is entirely free from them. An example of a cross section of an ingot-iron ingot is shown on page 16 of "Research and Methods of Analysis of Iron and Steel," published by the American Rolling Mill Co. (1920). A certain amount of pipe may also occur in rimmed ingots, though it is normally porous and not as well defined or deep as in the killed ingot of Fig. 1. In killed ingots, pri-mary blowholes may occur near the surface, as in Figs. 2 to 4, and

Jan 1, 1937

By C. S. Matthews, G. L. Stegemeier

In one field in South Texas, approximately 72 per cent of the pressure build-up results show a characteris-i.rtic "hump" (i.e., the pressure builds up and then falls off) which makes interpretation by. standard methods impossible Correlation of size and time of hump with formation permeability. well productivitv index, and method of completion led to the tentativc, conclusion that the humps were caused by segregation of gas and oil in the wellbore after closing-in"&apos;. This conclusion was confirmed by performance of simple laboratory bubble-rise experiments, by theoretical bubble-rise time calculations, and by a detailed calculation of PVT behavior in the well of a particular well Oil which accurate Surface and bottom-hole pressure measure-ments were untile. The hump behavior has since been found to occur in many other fields. The cause, however, is not the mine in all cases. In some of these the hump is trace-ahie to leaks in the tnbing which allow influx from the annulus after closing-in. In other cases the hump is traceable to leaks in the device separating pay horizons in dually completed wells. It is concluded that the recording of both surface and bottom-hole pressures is desirable in wells which show an anomalous build-up behavior. A number of field examples is discussed where use of both sets of measurements enables the cause for anomalous behavior to he found, (and a reasonable interpreation of bottom-hole pressure to be made. INTRODUCTION Theoretically the pressure build-up in an infinite reser-voir should be a linear function of In [(t + at)/nere t is the production time and At a the closed-in time. Some of the variations from this behavior arc well known, such as the curved portion immediately after shut-in which results from after-production and skin effect, and the flattened end portion which results from boundary effects in a limited reservoir. The effect of stratified producing zones and irregular geometrical drainage patterns may also contribute unusual characteristics to build-ups. However, the effect of still another phenomenon—that of movement of fluids within the wellbore—has been neglected in most build-up studies to date. Fluid movements within the wellbore after shut-in occur as a result of after-production, packer failures, leaks in the casing or tubing, or buoyancy of the gas phase when both gas and liquid are present in the well. Each of these movements can influence the pressure build-up, sometimes sufficiently to negate use of the data for computing permeability or stabilized build-up pressure. Examples of each of these phenomena are discussed below. FIELD OBSERVATIONS ON HUMP BUILD-UPS In approximately 75 per cent of the wells in a medium-sized field in South Texas the pressure build-up curves rise to 3 maximum and then decline to what appears to be a stabilized reservoir pressure as shown in Fig. I. Similar behavior has also been observed in wells in other fields in Texas and Louisian:,. Because of the possibility of such behavior being a mechanical failure of the pressure bomb. the bombs were run in tanden into one well which had been known to exhibit this behavior. When both bombs recorded identical curves with the characteristic hump, it was inferred that the unusual build-up is a result of well or forma-

By E. Swartzman

THE free-swelling index, a numerical value for the free-swelling properties of coal, is being used to an increasing extent in specifying coal for burning in various types of equipment. The empirical standard ASTM method for determining this index uses, as a source of heat, a gas burner which requires frequent calibration because gas pressures are not constant, relatively small changes in gas pressure resulting in rather wide variations in the temperature attained in a crucible and thus in the resultant size of the coke button. Furthermore, the quartz crucibles specified for the test are not standard equipment, and relatively small variations in dimension and wall thickness from those specified often result in rather wide variations in the resultant size of the button.

Jan 10, 1951

By E. S. Wheeler

THE rapid increase in the use of monel metal and malleable nickel in the form of sheet, rod and tube has resulted in a similar increase in the demand for these metals in the form of castings. These castings range in size from small valves and pipe fittings weighing a few ounces to large centrifugal pumps, gate valves and marine propellers, some of the latter weighing as much as 24,000 lb. A group of such castings is shown in Fig. 1. A large nickel agitator is shown in Fig. 2. FIG. 1.-A GROUP OF MONEL METAL AND NICKEL CASTINGS. Monel metal castings are widely used in accessories for steam power plants and in a variety of chemical plant. equipment where the corrosion resistance, high strength and toughness characteristic of this metal render it particularly valuable. Nickel castings find extensive use in the construction of corrosion resistant apparatus, and are often used in conjunction with wrought nickel sheet and tube in the fabrication of equipment for handling a variety of chemical and food products, particularly dairy products. In response to this demand for castings, numerous foundries have undertaken the production of castings of these metals and have met with varying degrees of success.

Jan 1, 1930

By R. W. Raymond

THE death of Privy Councilor Bruno Kerl, on March 25, 1905, terminated a distinguished and useful career. Bruno Kerl was born March 24, 1824, at St. Andreasberg in the Harz, and entered in 1840 the mining school of Clausthal, where he studied for three years, working at the same time in the mines and stamp-mills. After an additional year of practice in the silver-reduction and iron-works of the Upper Harz, he passed his examination as a metallurgical graduate, and studied for a year at Göttingen under WV filer in chemistry, Hausmann in mineralogy, and eminent teachers in other branches. In 1846 he was employed at the Oker works, but very soon left this post, to become a tutor in chemistry, metallurgy, etc., at Clausthal, where he continued to labor until 1867. During this period the Clausthal school became a completely equipped Mining Academy, and Kerl was made in 1862 a full professor. Meanwhile, in addition to the work of instruction, he discharged, simultaneously or successively, the duties of many responsible official positions in the Royal Hanoverian administration of mines and smelting-works, and also published many valuable books and treatises. Among these were professional guide-books to the Upper and Lower Harz, and their characteristic metallurgical processes; a manual of qualitative and quantitative blow-pipe analysis; another of metallurgical assaying ; and, most important of all, a Handbook of Metallurgy in four volumes, the second edition of which was issued in Leipzig, 1861-1865. This book was speedily recognized as the leading authority in its field. In this country, the English translation and revision, by Crookes and Röhrig, published about 1869, had a large circulation. In addition to these literary labors, Prof. Kerl became in

Jul 1, 1905

The word "engineering" should not be considered as all-inclusive. Perhaps it should be redefined at this time. Various fields of learning that are indispensable to the locating, beneficiating, processing and using of minerals cannot be classified properly as engineering. For example, in locating deposits, the sciences of paleontology, stratigraphy, mineralogy, petrology, petrography, geo- chemistry, economic geography, and mineral economics might be involved. Beneficiating, processing, and using go beyond the normal scope of engineering to include fuel technology, physical and organic chemistry, physical and atomic metallurgy, and ceramics. Fifty-eight institutions of higher learning in the United States offer curricula in one or more subject-matter fields of the mineral arts and sciences. Thirty-four curricula are offered in mining; 42 in metallurgy; 17 in petroleum and natural gas; 13 in ceramics; 1 in fuel technology; 23 in geological engineering; 8 in geology; 4 in geophysics; 2 in mineral preparation; and l in mineral economics.1 Under given conditions, some of these curricula probably could be eliminated without the slightest retardation in the rate of advancement of knowledge concerning the science of mineral discovery, extraction and utilization, but it is no credit to mineral industries colleges that five departments of mining per-

Jan 1, 1950

By E. S. Wheeler

The rapid increase in the use of monel metal and malleable nickel in the form of sheet, rod and tube has resulted in a similar increase in the demand for these metals in the form of castings. These castings range in size from small valves and pipe fittings weighing a few ounces to large centrifugal pumps, gate valves and marine propellers, some of the last weighing as much as 24,000 lb. A group of such castings is shown in Fig. 1. A large nickel agitator is shown in Fig. 2. Monel metal castings are widely used in accessories for steam power plants and in a variety of chemical plant equipment where the corrosion resistance, high strength and toughness characteristic of this metal render it particularly valuable. Nickel castings find extensive use in the construction of corrosion-resistant apparatus, and are often used in conjunction with wrought nickel sheet and tube in the fabrication of equipment for handling a variety of chemical and food products, particularly dairy products. In response to this demand for castings, numerous foundries have undertaken the production of castings of these metals and have met with varying degrees of success. The successful production of castings of monel metal and nickel requires careful attention to molding practice, proper melting equipment

Jan 1, 1930