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By Otis Hutchins

IT is intended to discuss in this paper the protection appliances used for high-temperature pyrometer installations involving the use of platinum couples and describe some of the characteristics of a new carborundum protection tube. Of all the components that go to make a complete pyrometer installation, the one given the least attention and the one about which there is the least exact information is the outer protection tube. This condition is unfortunate as much, and in some cases even the success of the equipment as a whole, depends on the proper type of protection. In the majority of cases, the installation is allowed to operate without attention until some part of the apparatus breaks clown. The outer tube is the component that usually fails and, more often than not, the failure causes breakage of the porcelain protection and ruin of the couple. This condition should be recognized and studied as it has a very important bearing upon the upkeep cost of pyrometer equipment. The cost of the outer protection tube is small compared with the cost of the platinum couple and procelain protection and it would well repay users of this type of equipment to replace their outer protection tubes at certain definite periods, which experience shows is necessary to prevent destruction of the platinum. Speaking generally, platinum thermocouple equipment is used for measuring temperatures over 2000° F. (1094° C.), and is used extensively for the control of brick and pipe kilns, glass pot furnaces, glass tank furnaces, heat-treating furnaces, open-hearth furnaces, and forge furnaces. A satisfactory protection tube must be sufficiently refractory not to soften at the maximum temperature within the furnace. It must be resistant to cracking clue to temperature changes, should be as nearly gas-tight as possible, and should be made of a material with a high thermal conductivity and great resistance toward erosion by the furnace atmosphere.

Jan 9, 1919

By A. H. Bell

The general principles of the gas-lift will not be described in this paper. Only specific details that have not been fully discussed in previous papers, or results that do not fully coincide with conditions previously described, will be dealt with. The principal points to be emphasized and for which supporting data are furnished are as follows: 1. Gas-lift installations usually have comparatively high efficiencies as compared with standard pumping equipment, when reduced to a basis of barrels produced per horsepower installed. 2. Advantages of high-pressure plants from the standpoint of operating efficiency and for the application of the gas-lift early in the life of flowing wells. 3. Evidence of increased ultimate yield through conservation of gas by the gas-lift. 4. Possibility of development of new equipment to increase efficiency of the gas-lift. 5. Indications of the advantages of repressuring as a means of stabilizing gas-lift wells and as a means of increasing ultimate yields. TyPes of Installation The gas-lift installations of the more important companies in California have been of the central-plant type wherever field conditions would permit. This has resulted in greater flexibility and lower installation costs per well than could be obtained with individual well units. In general discussions of the gas-lift method of production, the installation costs are frequently referred to as being too high for economical operation. If the field conditions are carefully analyzed and the plant designed with the idea of obtaining high operating efficiencies, the installation cost per well can be lowered sufficiently to compare favorably with individual well-pumping units, when the operating advantages are considered. Much greater production per horsepower can be obtained with the gas-lift than is possible with pumping equipment. Table 1 shows the unit sizes and costs of gas-lift installations of three companies in the Los Angeles basin. The cost of walking beams, rods,

Jan 1, 1928

By W. E. Wrather

The overproduction of crude oil in 1927 has received such widespread publicity, both within and without the industry, and the several factors which have brought about this situation are so thoroughly agreed upon by everyone, that it is unlikely the writer will in this brief review be able to contribute anything new. The entire story of low prices and demoralization revolves around two flush districts, Seminole and West Texas— the actual. performance of Seminole and the potential threat of West, Texas. The sustained production of California has been a contributing factor to this situation also. It seems reasonably certain that Seminole and West Texas will together dominate the industry during 1928, with Seminole probably destined to drop into second place, as additional pipe lines are completed into West Texas to care for its rapidly expanding production. It now appears inevitable that the production of 1928 will equal or exceed that of the past year, depending solely upon the rapidity wit,h which it is possible to market West Texas crude, and the degree of restraint which operators are willing to impose upon themselves in holding proved reserves of oil underground. Adversity has cultivated the growth of a promising spirit of cooperation which has accomplished practical results both at Seminole and in West Texas. Cooperation among oil producers has long been ardently hoped for, but prior to the past year it has never been effective on an important scale. The interests both of the industry and the public at large can best be conserved by cooperation in controlling production, and the widespread acceptance of this idea has paved the way for a more rational policy in the immediate future Production BY Major Districts The domestic production of the United States during 1927 amounted to 894,43.5,000 bbl. (Bureau of Mines), an increase over 1926 of approximately 128,000,000 bbl. California succeeded in maintaining its position of the past four years at 230,000,000 hbl. In 1923 with the Los Angeles

Jan 1, 1928

By A. C. Milner

In a gold standard world which possesses insufficient metal to meet the every-day needs of all, confidence becomes the vital factor, the very foundation upon which the machinery for the expansion of gold into currency, and credit, rests. The gold supply, affected by many influences, moves constantly from one point to another, but not always to that point where it is most needed. In the period 1928-1930, the combined gold holdings of the United States and France increased $1,370,936,-000, and this with new gold adding only $600,000,000 to the monetary gold stock.Theref ore, the gold stocks of other countries must have been depleted during the period by $770,936,000. This uncontrolled shifting throws the delicately adjusted instrumentalities of both credit and commerce out of equilibrium. If a given nation's gold stock shifts so as to bring it substantially below the legal reserve ratio set up against it for currency issues, the effect can easily extend to the currency issues and banking credit volume of one or more nations which may have based their gold exchange standards upon the gold stock of such nation. Thus the substitution of paper based on gold in place of the actual gold is an inflation of the currency, which carries through into an uncontrolled pyramiding upon the entire machinery of credit based on gold. In 1929 Europe, South America, Africa and Asia had overissued currency based on gold. America, Oceanica and Japan, which have not overissued their gold currencies, would in normal times require their entire present gold stocks and, as Continental Asia is largely upon a silver credit basis, from a domestic standpoint, it would appear that the gold problem is not so much one of maldistribution, as it is one of inadequate supply. It would appear that some method of increasing greatly the velocity of gold, within the safe reserve point, should be devised, or that silver, of which estimates indicate that 7,000,000,000 oz. are available for

Jan 1, 1931

By H. W. Morse

MANY of our largest copper deposits contain both sulfide and oxidized copper minerals. The large porphyry mines, with a total copper content of from 1.3 to 2.0 per cent., send to their mills ore with an oxide content of from 0.2 to 0.4 per cent. While the recoveries of the sulfide minerals are considered satisfactory, using modern flotation practice, the recovery of the oxi- dized portion of the copper is small; better recoveries of oxidized copper were made before flotation methods were adopted. Beside the ores containing copper mainly as sulfide, with a small amount of oxidized copper,, many of the large porphyry mines have oxide orebodies, in which the propor-tion of non-sulfide minerals is so high that 2 present methods of treatment are ineffi-cient. In some of the well-known ore-bodies in the Miami-Inspiration district the copper occurs about equally in sulfide and oxidized forms; and the mixing of minerals is complete throughout the ore-body. There is no possibility of mining the sulfides and the oxides selectively. At the New Cornelia mine, however, the oxide, and sulfide ores are sharply separated, per-haps by an ancient water level, so that the oxide ore may be mined and treated in a plant built for that purpose, and the under-lying sulfide ore may be left for treatment in another plant. If copper is to be made from an ore having a total content of 1.5 per cent., it must be concentrated or removed from the ore by some. hydrometallurgical method. Flotation is generally successful for the sulfide minerals and flotation after filming with sulfide seems to work in many cases on the pure carbonate minerals. Callow has given an extensive report on the results of "sulfidizing" flotation on the ores of the. Magma mine.1 Where such ?a 'method can be applied, it ?may be, the best

Jan 9, 1922

By T. F. Bower, M. C. Flemings

The classical explanation for formation of the fine equiaxed "chill zone " in ingot solidification is that local supercooling near the chill wall causes copious nucleation in this region. This work indicates, however, that convection is an essential element in formation of the chill zone. In the absence of convection, no chill zone forms even though rate of. heat extraction is extremely vapid. Alloy studied was Al-l.5 pct Cu alloy solidified against a copper chill wall. When solidification was initiated at the chill wall in absence of. cor-vection, surface grain size was large (>I cm diam). When it was initiated in the presence of convection, it was fine (<0.05 cm diam). It is concluded that some form of "crystal multiplication" plays an important role in formation of the chill zone. INGOT macrostructures are generally classed as containing one or more of the three zones: "chill zone", "columnar zone", and central "equiaxed zone". These three zones are sketched in Fig. 1; their origin has been discussed in some detail.&apos;-&apos; The classical explanation for formation of the chill zone is that supercooling occurs in the region of liquid metal adjacent the mold wall, and copious nu-cleation then takes place in this region forming numerous small crystals. The columnar region then results by growth of favorably oriented grains (den-drites) which crowd out their less favorably oriented neighbors."5 The mechanism of the columnar-equiaxed transition has been the subject of considerable interest. The generally accepted mechanism, until recently, was that constitutional supercooling developed in front of the growing columnar grains with eventual nucleation of new, equiaxed, grains ahead of the growing solid front.&apos; Recently, it became evident this explanation was not completely satisfactory and it is now evident that "crystal multiplication" plays an important role. This crystal multiplication occurs by separation of dendrite arms from growing dendrites,8?"&apos; and has been shown to be strongly influenced by convection.6, 10-13 Reduced convection results, for a given alloy, in longer columnar zone, larger columnar grains, and larger equiaxed grains.7, 12

Jan 1, 1968

By Charles M. Means

A thoroughly modern coal-handling system has been installed at the Pittsburgh Terminal H. H. &. Coal Co.&apos;s new No. 8 shaft, or Cover-dale mine, about 11 mi. (17.7 km.) from Pittsburgh on a spur of the Montour R. R. The Pittsburgh scam, which is the one worked, is reached at a depth of 342 ft. (104 m.). Power is delivered to the mine at 22,000 volts over a transmission line of the bow-arrow type of construction. A private telephone line connecting the various mines and the main office in Pittsburgh is carried on the same poles. The high-tension line is brought to an outdoor, step-down, transformer substation, where three 833-kv.-a., single-phase, 60-cycle, oil-insulated, self-cooled transformers reduce the potential to 2300 volts. The transformers are protected by electrolytic, aluminum-cell lightning arresters, horn gaps, and choke coils. High and low-tension busses, together with fuses, choke coils and air-break horn-gap switches with thcir remote-control operating mechanism are mounted on a substantial structural-steel tower 25 ft. (7.6 m.) in height. Mine Substation The transformer substation is adjacent to a. pressed-brick building that houses direct-current substation equipment together with switchboards, etc., for the control and distribution of power. This building also contains the hoist for the men and supplies. Main Switchboard The 2300-volt circuit is carried underground in a conduit from the transformer substation to an oil switch in the substation and supply hoist building. This is the main switch controlling the 2300-volt busbars mounted back to a twelve-panel black-slate switchboard. From the switchboard, 2300-volt circuits are carried to transformers feeding the street and house lighting systems and to other transformers furnishing power for the elevator and lighting circuits in the store building. Other 2300-volt circuits run from this switchboard to the main hoist building, fan house and auxiliary or man-and-supply hoist. High-tension wiring,

Jan 1, 1922

By G. Sachs, E. J. Ripling, J. J. Lynch

INTRODUCTION General IT is general practice to evaluate the strength properties of a particular metal from its stress-strain [(S1 - E1]) curve obtained by means of a conventional tension test. Such a stress-strain curve, Fig I, illustrates two important properties of a metal, its ability to strain harden, and its ability to withstand a certain limiting stress, the "fracture stress,"[ (s&apos;r)], and a certain limiting strain, the "ductility" [(e1)], before it fails by separation. These two fracturing characteristics are the coordinates of the point of fracture in Fig I. In the case of a metal which necks in a tension test, both the fracture stress and the ductility (measured in a tension test) are dependent upon (a) the shape of the neck and (b) average values of the stresses and strains over the cross section at the moment of fracture. However, for the purpose of this investigation, these average quantities, rather than the actual values, may be considered for reasons of simplicity. It appears that the conclusions also hold true if the analysis were carried out for actual values of fracture stress and ductility at the locus of failure. In this paper, the effects of straining (at room temperature) by various methods on [ ] the above metal characteristics, which were determined by subsequent tension tests will be discussed. According to our present knowledge, any such prestraining results in a stress-strain curve (in subsequent testing by tension), Fig 2, the general shape, or flow characteristics, of which can be derived from the original stress-strain curve of the unstrained metal minus a certain portion exhausted by the initial straining. This phenomenon is called strain hardening, and may be measured by the magnitude of the cut-off, or the "effective strain," from which the new curve must start in order to coincide in its plastic branch with the original stress-strain curve.

Jan 1, 1948

By R. N. Lambert

This chapter discusses the evolution of high-speed shaft sinking in the South African goldfields. Whether we are talking of an additional shaft at an existing mine or the opening of a new mine, the increasing depth of the ore-bearing reef and the unremitting inflation of costs have provided the compelling incentive to shorten the time taken to sink a shaft and start earning revenue. The high costs of sinking a modern shaft system in South Africa are indicated by the recent example of a deep-level mine in the Orange Free State where the cost was nearly $22!42 million. This was for a single large shaft of 33 ft 6 in. diam (in all cases, shaft diameters refer to the finished diameter of the shaft, e.g., inside the concrete) and 7600 ft deep with a prestressed concrete brattice wall dividing the shaft into upcast and downcast compartments. Higher costs and the consequent demand for increased tonnages, deeper shafts with higher rock temperatures, which necessitate highly sophisticaled ventilation and refrigeration requirements, have all accentuated the importance of time in a shaft-sinking operation. Rectangular shafts with their simple design and comparatively reasonable sinking speeds remained popular for many years until greater mining depths combined with a host of the other allied problems inevitably led to changes in shaft design. Circular shafts appeared to offer many advantages, particularly when considering ventilation, strength, mechanization, and sinking through bad ground and heavily watered zones. However, these advantages were largely offset by the slow rate of advance necessitated by the need to stop sinking in order to line the shaft. The development of the curb ring which enabled lining to take place above the bottom of the shaft and the use of multideck stages allowing sinking and lining to be carried out concurrently resulted in a major break- through. Rectangular shafts, which are still popular elsewhere, have been superseded in South Africa by circular shafts which are almost without exception the only shafts sunk in our goldfields today.

Jan 1, 1970

By R. J. Schilthuis, T. V. Moore

In a previous paper,&apos; the results of some experimental work on the measurement of slippage in the flow of oil and gas mixtures through vertical pipes were presented. The data obtained were correlated and equations were deduced from which the performance of the experimental gas-lift could be predicted with reasonable accuracy. However, attempts to apply the equations to the calculation of pressure drops in actual flowing wells yielded erroneous results. At the time the results of the experimental work were published, no satisfactory explanation could be offered for the failure of the empirical equations to express properly the performance of wells. However, recent work has led to the development of a new hypothesis which presupposes certain conditions affecting the flow of oil and gas in wells. When the proposed equations are corrected to allow for these conditions, an agreement between the observed and calculated performance of the actual wells is obtained which in most cases is quite satisfactory, although it is subject to certain limitations. In this paper, the method of calculating the pressure drop in actual wells is considered, and the application of the method to the design of tubing is discussed. (For nomenclature used in this discussion, see Table 1.) Factors Affecting Slippage and Efficiency At the outset, a few of the principle factors affecting slippage and efficiency in the gas-lift discussed in the previous paper will be reviewed. In the flow of the mixture of oil and gas in a vertical pipe, slippage is the phenomenon of gas moving upward with a. linear velocity greater than that of the oil. Under steady conditions, if given quantities of oil and gas enter the tubing per unit of time, the same quantities of oil and gas per unit time must, on the average, pass every section of the tubing; otherwise, there would be accumulation or depletion of the oil or gas at some sections, and the flow would be unsteady. Therefore, if the gas is to flow at a greater linear velocity than that of the liquid,

Jan 1, 1933

C. H. MATHEWSON, New Haven, Conn. (written discussion *).-In a recent discussion of Dr. Jeffries&apos; paper on tungsten,1 J. C. W. Humfrey,2 after taking exception to certain of the author&apos;s ideas relative to the cohesion of A and C metal, expresses the opinion that future research is likely to develop a method of preparing tungsten possessing "mechanical properties in line with those of other metals." The present paper by Dr. Jeffries begins with a determination of comparative properties of tungsten, copper, and iron, in which much dissimilarity is apparent, and ends with a coherent explanation as to why much of this dissimilarity is natural and inevitable, thereby supplying theoretical means for visualizing the changing properties of metals in general, once certain fundamental facts are known. The author&apos;s reasoning is primarily from the standpoint of the amorphous theory and his principal achievement is the development of an idea f differential cohesion according to conditions of temperature, etc., between A and C metal (which was first plainly suggested by Rosehain and Ewen, in their papers on Intercrystalline Cohesion of Metals) along with associated ideas, so as to give us a really useful working theory. I have come rather reluctantly to believe in the amorphous theory, or some theory admitting a modification of the ordinary crystalline phase so as to permit differential properties within the conglomerate, mainly because in no other way does it seem possible to account for observed changes of properties with temperature, etc. The very best illustration f the competency f the amorphous theory in this respect is seen in this and other recent papers by the author. All fractures through normal or healthy metal that have been preceded by deformation are supposed, by Dr. Jeffries, to take place either through the amorphous phase or at certain boundaries between amorphous and crystalline material; his reference to fractures, both members of which are similar in appearance and do not reveal a preexisting coarse-grained structure because of a coating of amorphous metal, indicates his preference for the former interpretation.

Jan 5, 1919

By W. O. Borcherdt

THE 650-ton underground mill of The Empire Zinc Company of Colorado (a subsidiary of The New Jersey Zinc Co.) serves the Eagle mine at Gilman in the Battle Mountain mining district of Colorado. The topography is rough, the mine and mill being under Battle Mountain and the adit entrance in the north wall of the canyon of the Eagle River, which is here a steel) gorge. The town of Gilman stands on a shoulder of the mountain at altitude 8975 ft., above sea level, along the Pike&apos;s Peak ocean to ocean highway and contains the company office and the usual facilities of a modern mining town. The railway contact is at Belden, altitude 8370 ft., at the bottom of the gorge directly below Gilman, where the westbound track of the Denver and Rio Grande Western Railroad is cut along the north bank and the eastbound track along the south bank of the river. A general description of the mine, mill and service facilities, with an account of the geology, character of the ore and methods of mining and milling having previously been published in a series of articles&apos;, this paper will discuss with as little repetition as practicable the reasons for building the mill underground rather than as a conventional structure, the methods of construction employed and the experiences gained in what is apparently the pioneer plant of this type and extent. There is a large historical background for underground plant construc-tion. From the dim past caves have been used for dwellings, stables, storage and shops. It was natural that where caves were available their many advantages led to their enlargement to suit convenience and where they were not available but the ground conditions, topography and, drainage were favorable, to the construction of artificial caves. In the vicinity of Epernay, France, extensive underground chambers protect the manufacture and storage of champagne-an intricate and ingenious application of chemical engineering-and in recent years these plants have been mechanized by the installation of conveyor systems. In the

Jan 1, 1937

By Thomas H. Sheldon

In the zeal for opening up new ore-bodies, or for extracting the ore from attractive bodies already opened up, we very often lose sight of the fact, that, after all, the operation of a mine is a business proposition, pure and simple, and, for the best working-results, should be treated upon a strict business basis. Of course, in every mine of consequence, a record is kept of expenditures and receipts, and such glittering generalities as " gross receipts," " net receipts," " mining expenses," and a per cent. profit," can be told to the cent; but does this record show economy of management, as compared either with the same record of other months, or with the record of other mines of the same class ? Moreover, if such a record shows that the cost of mining is high, does it in any way enable the manager to put his finger on the leakage ? Does it necessarily follow that a mine which makes a profit of, say, 40 per cent. on 25-dollar ore, is doing less economical mining than one which saves 60 per cent. on 80-dollar ore ? Of course the figures in the latter case look the more attractive; yet when it comes to the point of saving everything which can be saved, and of cutting down expenses to the lowest possible cost of operation, the former mine is doubtless on the firmer and more economical financial basis. But as to the relative merits of the system of mining in the two cases, nothing could be decided without a basis of detailed comparison ; if one system is more economical than the other, why is it so, and wherein does the advantage lie ? This can be shown only by keeping accurately the cost of each mining operation. And no matter how dissimilar two mines may be in character and operation, yet there are a few general heads common to all mining operations. In the first place, it is necessary to break the ore from the solid ground;

Jan 1, 1907

By W. O. Borcherdt

THE 650-ton underground mill of The Empire Zinc Company of Colorado (a subsidiary of The New Jersey Zinc Co.) serves the Eagle mine at Gilman in the Battle Mountain mining district of Colorado, The topography is rough, the mine and mill being under Battle Mountain and the adit entrance in the north wall of the canyon of the Eagle River, which is here a steep gorge. The town of Gilman stands on a shoulder of the mountain at altitude 8975 ft., above sea level, along the Pike&apos;s Peak ocean to ocean highway and contains the company office and the usual facilities of a modern mining town. The railway contact is at Belden, altitude 8370 ft., at the bottom of the gorge directly below Gilman, where the westbound track of the Denver and Rio Grande Western Railroad is cut along the north bank and the eastbound track along the south bank of the river. A general description of the mine, mill and service facilities, with an account of the geology, character of the ore and methods of mining and milling having previously been published in a series of articles1, this paper will discuss with as little repetition as practicable the reasons for building the mill underground rather than as a conventional structure, the methods of construction employed and the experiences gained in what is apparently the pioneer plant of this type and extent. There is a large historical background for underground plant construction. From the dim past caves have been used for dwellings, stables, storage and shops. It was natural that where caves were available their many advantages led to their enlargement to suit convenience and where they were not available but the ground conditions, topography and drainage were favorable, to the construction of artificial caves. In the vicinity of Epernay, France, extensive underground chambers protect the manufacture and storage of champagne-an intricate and ingenious application of chemical engineering-and in recent years these plants have been mechanized by the installation of conveyor systems. In the

Jan 1, 1937

By H. J. Hand

STATISTICAL methods are becoming increasingly important for interpreting routine reports, or for analyzing special test data in industrial plants, such as steel plants. They have already become practically a necessity to the plant metallurgist. A paper by Chancellor,&apos; written in 1933, gives many examples of the benefits the plant metallurgist can derive from the use of these methods. The present paper discusses applications of importance to many others who must analyze reports in the steel plant, as well as other examples of interest to metallurgists. Statistical Methods Logically Suited to Plant Problems.-Statistical methods are not new as a branch of mathematics. Until comparatively recently, however, practical applications were confined mainly to actuarial science,, biology, and economics; fields in which an observed result is obviously influenced (and often determined) by a complicated set of variables more or less constantly tending to affect it. As pointed out by Daeves,2 a decade or more ago, problems in industry are basically similar to those in these other fields in that a given result is at least partly due to that chance combination of causes happening to be present at the time. When trying to do the same thing repeatedly, constant results are never attained; they vary about the desired result with more or less well defined mathematical regularity. Such a condition arises out of the great number of factors tending to affect the final result. If statistical methods are so valuable to the biologist or economist, why then should .they not also be of great value to plant managers and engineers, and to all who must interpret reports from various sources in the industrial plant? Within the last few years, industry has become conscious of this situation, and the use of these methods has been rapidly expanding in such plants. † Many Useful Statistical Devices Available.-Many statistical methods of attack are available for the analysis of plant data. It is the object of this paper to discuss applications of some of these methods to the solution

Jan 1, 1938

By E. B. Harden, J. H. Harden

The practical use to which topographical models or relief-maps have been put, has within the last few years taken a wider range. They are rapidly coming into favor for other than purely scientific purposes, and their value for illustration and instruction is being more fully appreciated. Topographical maps; representing by contour-curve lines the elevations and depressions of the earth&apos;s surface, are now demanded in engineering work of nearly every description, and afford a ready means of bringing out the configuration of the country in a simple manner. A beautiful example of recent topographical mapping is seen in the seventeen sheets just issued by the Geological Survey of New Jersey. By reason of the inability of unskilled persons to understand the nature of a topographical map, it is sometimes necessary to con struct the same in relief, with the rivers, canals, railroads, etc., delin eated upon it. With the aid of such a map, problems in engineer ing science which would otherwise require expert assistance to explain them, are reduced to a simple and understandable form. Relief-maps are also of value to the geologist in working out the geological structure. To the instructor they present the most ready and efficient means of imparting clear and accurate knowledge of topography and kindred subjects. To the lawyer they are invalua ble in enabling him to bring into the court-room a representation of a part of the country with all its features accurately shown, to ex plain to the court and jury the special points about which litigation is pending and which would otherwise require long and laborious description. The application of the topographical map to business purposes is shown in a relief constructed by the writers for the Cumberland Valley Railroad Company and used by that company in the various ways of calling attention to the desirability of its route. This model is based partly on actual survey and partly on sketch topography. The horizontal scale is ,%, the vertical 1/19,200 of

Jan 1, 1888

By H. M. Chance

(Butte Meeting, August, 1913.) ADEQUATE treatment of the difficulties surrounding the valuation of mineral lands requires that agreement be first reached defining value as understood for the purpose of appraisal. To define value as the price of a product is not sufficient, and does not assist us in using the factors that cause variations in values and in relative values. The real value of any product depends primarily upon its relation to the necessities, comforts and pleasures of mankind. As the necessities, comforts and pleasures of the civilized races differ from those of more primitive man, the value of products varies with the degree of civilization and the environment of the consumer. Coal has no value to the savages of warm climates, and arrow-head flint none to the residents of New York. It has long been recognized that what has been termed ? intrinsic value " must be limited to materials that are essential to existence-air, water, food. But "intrinsic value" cannot be measured in monetary terms. The intrinsic value of a bushel of wheat is due to the fact that it will support the life of an individual for a certain definite time, but this fact does not enable us to measure or to express that value in monetary terms. It has often been proposed to adopt as a measure of the value of any product the quantity of labor necessary to produce it, but this method is of limited application, and will not apply to what may be termed "intrinsic values." For many reasons it might be well, while assenting to the fact that any material may he intrinsically valuable, to abandon the use of the term " intrinsic value." One of these reasons is the tendency to confuse the idea of intrinsic value with a value that is conferred by economic conditions, that is purely artificial and that may be permanent or evanescent; Intrinsic value must from its nature be permanent and unchangeable.

Jan 7, 1913

By E. A. Barnard

ARSENIC is a very old substance. The ancients speak of it in their writings, and its use has developed very little until recent years. The ancients used it in making pigments, in medicine, and for poison. They also tell of the difficulties of handling it-an experience which is very similar to our own. Until about 10 years ago, arsenic was very cheap and was a drug on the market. About that time the boll weevil began making serious inroads on the American cotton crops, and after much investigation the Depart-ment of Agriculture developed a very successful poison for this pest, consisting of calcium arsenate. The weevil pest has continued, and as the cotton planters have become convinced that calcium arsenate is the best material to use against the weevil, the demands for it have been steadily increasing, resulting not only in a rising price of arsenic but in a very serious shortage so far as our country is concerned. So serious has this shortage become, and so vital is it to the cotton growing industry, that Congress has appointed a committee to investigate and report on the situation. A meeting of arsenic producers and consumers was held in New York last December to take stock of the situation and to see what could be done. The extreme increase in, the market price of arsenic-from 6 c. to 15 c. per lb. in less than a year-has been very harmful to the producers as well as to the consumers. Some very interesting&apos; data were brought out at this meeting, as follows: CONSUMPTION PER YEAR, SHORT TONS Arsenate of lead 2,000 Paris green 1,200 Proprietary mixtures 750 Sheep dips : 1,000 Weed killers 1,500 Glass : 2,000 8,450 1922 Consumption as calcium arsenate 4,000 12,450 1923 Estimated consumption as calcium arsenate... 12,000 Estimated 1923 consumption 20,450

Jan 8, 1923

By H. M. Chance

(Butte Meeting, August, 1913.) ADEQUATE treatment of the difficulties surrounding the valuation of mineral lands requires that agreement be first reached defining value as understood for the purpose of appraisal. To define value as the price of a product is not sufficient, and does not assist us in using the factors that cause variations in values and in relative values. The real value of any product depends primarily upon its relation to the necessities, comforts and pleasures of mankind. As the necessities, comforts and pleasures of the civilized races differ-from those of more primitive man, the value of products varies with the degree of civilization and the environment of the consumer. Coal has no value to the savages of warm climates, and arrow-head flint none to the residents of New York. It has long been recognized that what has. been termed ?intrinsic value " must be limited to materials that are essential to existence-air, water, food. But " intrinsic value " cannot be measured in monetary terms. The intrinsic value of a bushel of wheat is due to the fact that it will support the life of an individual for a certain definite time, but this fact does not enable us to measure or to express that value in monetary terms. It has often been proposed to adopt as a measure of the value of any product the quantity of labor necessary to produce it, but this method is of limited application, and will not apply to what may be termed " intrinsic values." For many reasons it might be well, while assenting to the fact that any material may be intrinsically valuable, to abandon the use of the term "intrinsic value." One of these reasons is the tendency to confuse the idea of " intrinsic value with a value that is conferred by economic conditions, that is purely artificial and that may be permanent or evanescent. Intrinsic value must from its nature be permanent and unchangeable.

Jan 7, 1913

By J. M. W. Mackenzie

A microelectrophoresis technique has been used to measure the zeta potential of quartz over a range of pH and ferric iron concentration. The results have been discussed in terms of the adsorption of ferric cations and ferric hydroxide to the quartz surface. Possible relationships between the experimental results and the flotation of quartz have been examined. The adsorption of multivalent cations at the surface of quartz has been studied by many investigators who have used a variety of experimental techniques ranging from streaming potential 1 to radiometric2 measurements. Two possible mechanisms of cation activation of quartz have emerged from the results of these investigations viz: the adsorption of the cation to the negatively charged quartz surface, followed by adsorption of the collector anion to the adsorbed cation site, or: formation of a cation-collector complex which is then adsorbed to the quartz surface. In many natural and industrial systems one of the most prevalent activating species for quartz is ferric iron, this is especially so in the acid-circuit, anionic flotation of iron ore. The adsorption of ferric iron to the quartz surface is complicated by the ability of ferric iron to form complexes with anions, a phenomena which is of minor importance in one of the most widely studied quartz activation processes, ca ++ activation.* *The pK value for [ca(oH)+]/ [ca2+] [oh-] is 1.46 indicating that the influence of Ca (OH)+ ions will be minor in all but strongly alkaline solutions. In order to obtain a better understanding of quartz activation by ferric iron the zeta potential of quartz in the presence of ferric iron has been measured over a range of pH and ferric iron concentration. EXPERIMENTAL METHODS Materials: Selected samples of "rock clystal" quartz from New England, N.S.W., were ground in a pebble mill, washed for three hours in boiling concentrated hydrochloric acid, washed in hot chromic acid and then washed repeatedly with distilled water until the washing water gave no trace of chloride ion.

Jan 1, 1967