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By Benjamin Gildersleeve

Uniquely colored, thin-bedded quartzite is quarried between Crossville and Crab Orchard in Cumberland County, Tenn. It is produced in all sizes up to the limits of transportation from beds usually ranging in thickness from less than Vi in. to 6 in. The stone is very resistant to wear and weathering and is marketed throughout the country for many different purposes in exterior and interior construction. The annual production exceeds 36,000 tons, valued at nearly $1,000,000. THE building stone of the Crab Orchard District is a fine-grained, thin-bedded sandstone which is so strongly cemented by silica that it may be classed as quartzite. As used in this paper the term building stone includes dimension stone, rubble, ashlar, flagstone, and rough broken stone. The Crab Orchard District is in the central portion of Cumberland County, Tenn. It is named from the town of Crab Orchard near which the stone was quarried first for industrial use. The heart of the district is an area of some 1200 acres from 1 to 3 miles east of Crossville which is 70 miles west of . Knoxville and 125 miles east of Nashville (fig. 1). At the present time, there are about 15 quarries worked by companies and individuals. Geology: The Crab Orchard District is on the Cumberland Plateau, or Cumberland Mountain as it is called frequently. Most of the area is characterized by a comparatively even surface from 1800 to 2000 ft in elevation and is drained by streams flowing into the Tennessee River. Included in the district are two quarries located 7 miles west of Cross-ville and this area is drained by tributaries of the Cumberland River. Most of the quarries are located near the 1800-ft contour which is just below the general upland surface. The surface rock over most of the district is the Rockcastle sandstone which has a thickness of about 260 ft.1 It is the topmost of the six formations of

Jan 1, 1951

By Persifor Frazer

During the Centennial year some of our leading geologists in the United States and Canada conceived the happy thought of calling an International Congress of Geologists for the purpose of agreeing upon such important though subsidiary matters as the colors by means of which the different geological formations should be expressed ; the terms that should be applied respectively to these formations; and also upon the far more important problem of the limits and values of these different formations. The first session of this Congress was held in Paris in 1878, the second session in Bologna in 1881, and the third session in Berlin in 1884. The third session found the preliminary difficulties so far cleared away that some definite and tangible results could be attained. After a great deal of free discussion had taken place at Paris and Bologna, during which every one's views were listened to with attention; and a great deal more painstaking scientific work had been accomplished by the International Committees, having before them the objects of unifying the nomenclature of the science, and of preparing a scheme of colors between the second and third sessions of the Congress; and after the provisional results had been subjected to a searching criticism by the Congress in Berlin; it was decided to make an attempt to embody these provisional results in some work which should include as many as possible of the difficulties to

Jan 1, 1887

By Benjamin Gildersleeve

Uniquely colored, thin-bedded quartzite is quarried between Crossville and Crab Orchard in Cumberland County, Tenn. It is produced in all sizes up to the limits of transportation from beds usually ranging in thickness from less than Vi in. to 6 in. The stone is very resistant to wear and weathering and is marketed throughout the country for many different purposes in exterior and interior construction. The annual production exceeds 36,000 tons, valued at nearly $1,000,000. THE building stone of the Crab Orchard District is a fine-grained, thin-bedded sandstone which is so strongly cemented by silica that it may be classed as quartzite. As used in this paper the term building stone includes dimension stone, rubble, ashlar, flagstone, and rough broken stone. The Crab Orchard District is in the central portion of Cumberland County, Tenn. It is named from the town of Crab Orchard near which the stone was quarried first for industrial use. The heart of the district is an area of some 1200 acres from 1 to 3 miles east of Crossville which is 70 miles west of . Knoxville and 125 miles east of Nashville (fig. 1). At the present time, there are about 15 quarries worked by companies and individuals. Geology: The Crab Orchard District is on the Cumberland Plateau, or Cumberland Mountain as it is called frequently. Most of the area is characterized by a comparatively even surface from 1800 to 2000 ft in elevation and is drained by streams flowing into the Tennessee River. Included in the district are two quarries located 7 miles west of Cross-ville and this area is drained by tributaries of the Cumberland River. Most of the quarries are located near the 1800-ft contour which is just below the general upland surface. The surface rock over most of the district is the Rockcastle sandstone which has a thickness of about 260 ft.1 It is the topmost of the six formations of

Jan 1, 1951

By William M. Brewer

History.—The history of gold-mining in Georgia and Alabama antedates the discovery of gold in California. A very large proportion of the gold used in the United States previous to 1849 was produced by these States. A great deal of this history is merely tradition, and no reliable statistics can be obtained ; yet a personal examination of the gold-fields of Georgia and Alabama indicates that tradition is as fairly reliable, with regard to the history of these gold-regions, as it is in any similar cases throughout the world. In Georgia, the history of gold-mining dates back to 1829, when the first gold-mining excitement in the United States occurred. In Alabama, the discovery of gold was made some years later through the work of prospectors, incited by the rich finds in the Georgia mining camps. The greatest product of gold in these States was between the years 1840 and 1849. In Lumpkin county, Ga., and Cleburne county, Ala., the districts from which the most of this gold was taken, the tailing-dumps are silent witnesses of the extensive operations which were carried on by the primitive and crude methods then known. It is no rare thing to see trees 12 to 15 inches in diameter, and even

Jan 1, 1896

By E. A. Beck

(New York Meeting. February, 1913.) For a number of years many attempts have been made to use thermit in order to do away with piping in ingots. Some of these attempts were successful, while others did not give the expected results. Nearly every plant had its own method of using the thermit, and no special care was taken to study, the results or to find the causes for lack of success. Formerly the principle of the process was to decrease the piping by introducing a can filled with thermit, attached to an iron rod, into the head of the ingot directly after it bad been poured. In this case the thermit reaction took place in the upper part of the ingot, and it was thought that through the heat produced the head would keep liquid longer and piping thus be reduced. In other words, the aim was to keep the head of the ingot open by making use of the heat of the thermit reaction, which would thereby give the gases in the steel sufficient time to escape. This result can be attained by the application of a large enough quantity of thermit, but it would not be economical in general practice, and could only be used for high-grade material. Many steel-makers abroad and in this country have had this experience. The Th. Goldschmidt A. G., Germany, has, therefore, made a special study of this question with the co-operation of a well-known steel company, and has worked out a new method for. the application of thermit for this purpose. The results obtained have been most satisfactory and reliable, and this- process is now used in Germany on a large scale in many prominent steel-works.

Jan 4, 1913

By H. A. Davies

DURING a current program of research on the structure and properties of liquid sodium alloys, the need arose for information on the solubilities as a function of temperature of several B subgroup metals in liquid sodium. In the absence of reliable information in the literature for several of these systems, par- ticularly at temperatures in the range 100° to 300°C, an apparatus was constructed to determine solubilities by a direct melt-sampling technique, followed by wet-chemical analysis for both sodium and the solute metal. The details of the technique have been described previously.' The solubility of indium in liquid sodium was determined at eight temperatures in the range 100° to 270°C. The solubility as a function of temperature is shown on Fig. 1; this represents the liquidus line over this composition range. A cooling curve was plotted after the completion of the sampling and an arrest was observed at 94.9°C which must be interpreted as being the result of a eutectic reaction. By extrapolation of the liquidus to this temperature, the eutectic composition was estimated to be about 0.25 at. pct In. The present estimate of the eutectic temperature and composition are in good agreement with the values of 96.0° to 96.2°C and between 0.28 and 0.45 at. pct In, respectively, which were reported by Heycock and Neville.2 However, no further information on the liquidus of this system at the sodium-rich end could be found in the literature for comparison. One compound: NaIn, has been reported in this sys-

Jan 1, 1968

By E. D. Gardner

VICTOR G. HILLS, Denver, Colo. (communication to the Secretary*).¬If anyone advocates the abolition of the antecedent mineral discovery requirement for the purpose of making it easier to secure title to public land, I hasten to say that I am not of that number. I am in Hearty accord with all that Mr. Gardner has to say in regard to easy patenting as a handicap to small camps, and that in general it acts to retard the mining industry. And the following sentences I want to repeat in order to emphasize and endorse them, "None of the writers on this subject seem to have taken into consideration the effect amending the law pertaining to mineral discovery will have upon the Government's administration of the public land. It must be borne in mind that this land belongs absolutely to the people of the United States as a whole, and their interest must be considered. It is not a no-man's land, as some people would appear to believe." However, I believe that the discovery prerequisite should be abolished, because it fails to effect the protection for which it was designed, and I look for other provisions that will better serve the purpose. We propose to abolish the law of apex not because the theory is objectionable but because the question of physical fact gives rise to never ending litigation. Now the design of antecedent mineral discovery is good; the court rulings are unobjectionable; but when it comes to the physical fact this requirement is second only to the apex law as a healthy litigation breeder. The only circumstance that has prevented the pre-discovery lawsuits from becoming as famous and as: expensive as the apex

Jan 12, 1916

By Harry L. McNeill

THE Selective Media Process was developed by the author in a laboratory provided by The Steårns-Roger Manufacturing Co. It is the outcome of an [ ] investigation into the possibilities of coarse beneficiation by sink and float without using the conventional heavy media. Commercial work to date has been limited to the treatment of minus 3/8-in. iron ore at the Hill Trumbull washing plant of the Cleveland Cliffs Iron Co., at Calumet, Minnesota. Two cut away prints of the machine are shown (Figs. I and 2). A rotary conical impeller is mounted within a stationary cone (Fig. 2). This impeller is adjustable vertically by a 12-ton screw jack. The speed of the impeller can be varied from 14 to 32 r.p.m. by the Reeves variable-speed motor pulley mounted on the 7 ½ -hp. motor drive. Attached to the bottom of the stationary cone is the automatic control valve for sink product, actuated by a ¼ -hp. gear motor. The sink product is dewatered in a conventional drag driven by a 7 ½ -hp. motor and discharged onto an inclined conveyor containing from 6 to 10 per cent moisture. Two plants are operated at the Hill Trumbull property. All the ore is first treated in a typical washing plant (Fig. 3). When treating "wash ore" a finished concentrate can be produced by the log washers and Akins classifiers, as the separation involves only fine silica (minus 48-mesh) and free iron. However, when "jig ore" is fed to the washing plant the coarse

Jan 1, 1946

By Merrill Horine

IT has been stated and accepted for many years that the automotive industry was the instigator, the principal sponsor for and the largest user of alloy steel and nonferrous alloys. The only universally recognized standard specifications and heat-treatments for these materials are those adopted by the Society of Automotive Engineers. It is this same auto-motive industry that has been the chief inspiration for and consumer of modern production machine tools. The production curve of steel ingots is more sensitive to fluctuations in automotive production than any other influence or group of influences. In every other important steel-con-suming industry, automotive materials and automotive processes are the outstanding features of modern progress. In this connection I need only mention the prefabrication of buildings, following the automotive system of straight-line, interchangeable mass production; the motorization of ships and railroads, employing automotive types of prime movers; the production of pressed-steel stoves, plumbing and furniture by methods originated in the automobile-body industry and the extensive use of rubber for the cushioning of all manner of machinery as pioneered by the automotive and tire industries. Dr. Jeffries has brought out this point in his address (p. 21), assuring us that the transportation industry is the largest user of these materials. In the transportation industry, or as we might more accurately express it, the transportation group of industries, the. automotive industry pre-dominates as a user of light alloys. One out of every four tons of aluminum produced is consumed by the automotive industry. Similarly, the automotive industry ranks first in the consumption of the following metallurgical materials: steel, 24.04 per cent; malleable iron, .57; alloy steels, 72.2; nickel, 30; lead, 39 per cent.

Jan 1, 1936

By George A. Yurko

The Cominco smelter, located at Trail, British Columbia, Canada, produces 180 000 metric tons of lead bullion annually in conventional blast furnaces. The resulting slag from these furnaces, 210 000 metric tons annually, containing 18 per cent zinc and 2.5 per cent lead, is treated directly in the slag fuming plant for the recovery of these metals and other valuable metals present in smaller quantities. Slag fuming is carried out on a 55 metric ton batch process in completely water-jacketed furnaces where the slag is blown with a mixture of powdered coal and air. The coal-to-air ratio is con- trolled to maintain strongly reducing conditions, thus, fuming the metals from the slag. The metal vapours are subsequently re-oxidized with air above the bath. The mixture of oxides is carried from the furnace by the gases through waste heat boilers and cooling flues to a baghouse where they are collected. The slag fuming plant, under normal conditions, will treat 700 metric tons of slag daily. The throughput in the plant is dependent on the fuming rate of zinc, which is a function of the composition of the slag, and on the economics, which dictate the extent to which zinc is fumed from the slag. Zinc and lead collected daily as fume average 113 metric tons and 17 metric tons, respectively, corresponding to recoveries of 89 per cent zinc and 98 per cent lead from the slag. The waste heat boilers produce 61 metric tons steam per hour, which is distributed to other processing plants.

Jan 1, 1970

By Theo B. Comstock

TO the large majority of visitors the unique features of the National Park are interesting chiefly on account of their novelty. Scientists of all schools may find here food for reflection, and much that is rare and marvelous; but the real, practical uses of the reservation, aside from its pleasure-giving adaptations, are not as yet fully appreciated. Since 1873, the writer has on frequent occasions expressed freely his own views upon the proper means of utilizing the Park for the best interests of science.* Some of the recommendations made have been adopted by the authorities. At the suggestion of friends I present here a brief statement of facts concerning matters which may be of advantage for visiting engineers to know, hoping that the very limited stay of the Institute may thereby be rendered a little more profitable, and that our common profession may possibly receive some benefit. First, then, it should be understood that, as in many other cases in. the West, the present routes to the Park from the south are not the most direct. The expedition of Captain (now Major) Jones in 1873 discovered a practicable route for a, wagon or railroad via the head of Wind River, through To-gwo-tee Pass and Two-Ocean Pass, by which the distance from Point of Rocks, Wyoming, on the Union Pacific R.R., to the Yellowstone Lake, is only 290 miles. Eventually, it is probable that a railway line from Cheyenne or some other point in Wyoming will be constructed, which, taking advantage of

Jan 1, 1888

By Utley Wedge

In general, the art of securing copper from sulphide ores or concentrates may be said to consist of: (1) separation, in the molten state, of copper sulphide with some iron sulphide, from the great bulk of gangue-material, followed by (2) elimination of sulphur and iron from the molten matte, by oxidation and fluxing, leaving metallic copper. The definition is made broad enough to cover the general practice, whether or not the ore or concentrate is given a prelimiuary roast for the removal of surplus sulphur. The above process, which I will designate as the smelting process, makes necessary the presence in the ore, or the addition thereto, of such silica, lime, and iron as may be necessary for the formation of a light and fusible slag, together with sufficient sulphur and iron for the formation of copper-matte, and also the addition to the matte of sufficient silica for the oxidation and fluxing-out of the iron. These items, together with the cost of fuel sufficient for melting the mass, constitute important items of cost in the copper-smelting process. Numerous cases where fluxing-materials are scarce or dear, or where fuel is expensive, have caused special attention to be given recently to the wet process of copper-extraction, which may be designated as consisting of forming soluble copper salts which are then washed or leached out of the ore or concentrates by dissolving in water or acid. Metallic copper may then be secured from the solution of copper salts by electrolysis; by cementation; or copper can be brought out of the solution as a hydroxide or other insoluble precipitate and reduced to metallic copper by subsequent melting in a reducing atmosphere.

Jan 1, 1913

By Charles F. Ramseyer

The manufacture of iron and steel is one of the largest of our industries; and in point of size of single plant and equipment certainly the biggest of all industries. By the general public it is generally considered a prime example both of the marvelous technical advances achieved by modern science and engineering in the design and operation of equipment and of the efficiency of big business in the coordination of men and materials. Actually the operation of its basic processes has not changed significantly in either theory or fundamental design of equipment in the past 75 years. Though many other process industries have been born and developed, and not seldom completely revolutionized, during this period, the primary processes of making iron and steel are still carried out along the lines laid down, and in the equipment originated so long ago, by Bessemer, Siemens and Martin, and subsequently expanded to practically the modern scale by Carnegie, Schwab and Captain Bill Jones in the eighteen eighties and nineties. The application of the principles underlying the continuous counter-current physical and chemical interaction of solids, liquids and gases, which have been so successfully used in the rapid evolution of our chemical process industries, has been very largely lacking in the steel industry. In the days of the last-named giants, especially Carnegie, the steel industry made great and rapid technical progress. Carnegie's ever driving idea (as later with Ford in the production of automobiles) was the finding of new and better ways of making cheaper steel. Carnegie himself was a steelman, and so long as he dominated the industry its technical progress was rapid; and he, like Ford, was vastly successful financially as well, since his costs were continually being driven lower than those of his competitors by his advances in steelmaking technique.

Jan 1, 1935

By Edward Keller

Under the title, Labor-Saving Appliances in the Works-Laboratory, I published a paper1 in which mas described how multi-manipulations in a works-laboratory and in the furnace-room of an assay-laboratory, can be condensed into single manipulations by applying the proper mechanical devices. For example, I now deposit ill, or withdraw from, a muffle a set of 48 cupels as one unit. The front row (8) of these are blanks or heaters; the other 40, when they have attained the proper temperature in the muffle, are charged simultaneously with the 40 lead-buttons. Three manipulations here accomplish an operation which by the generally customary method requires 136, and this number is only limited by the size of muffle and cnpels. This operation is an enlargement of what I have already described in my former paper, and Fig. 1 shows the improved implements. In the paper referred to I described a gold-silver bead parting-bath, which is the last of the devices used in regular sequence in practice. This bath mas designated as being convenient, but mas not a labor-saver properly. Fig. 2 of the present paper shows a new device. Instead of the original tray, there are now sectional holders for the test-tubes, each having a wooden handle on either end, so that the holders ma?-be removed from the boiling bath, and the acid or water poured oE from each set of tubes (in this case, 7) without waiting to cool. The tubes, held in place by clutches, as shown in Pig. 3, rest in holes in the base-strip, having a smaller diameter than the tubes. Each holder is stamped at either end with a number, so that the bath becomes further useful by permitting several men to use it at the same time without interference. Apart from the handles, the holders are made of sheet-copper.

Jan 1, 1911

TO THE BOARD OF DIRECTORS OF THE AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS Gentlemen: - I herewith present a report of some. of the more important activities of the Institute for the year of 1922. The outstanding feature of the year is the optimism felt by our members despite the continued depression in the mining industry. January 1, 1921, found many of our members out of employment or drifting into other industries to tide them over the depression, but almost universally the feeling has been that this was but a temporary condition and that sooner or later the necessary production of raw materials would enable these members to return to their former activities and renew their participation in Institute affairs. As the year passed conditions improved and, before it ended, many had found employment in their previous occupations. Bearing in mind that this depression has been very real, we have reason to be well satisfied with the work that the Institute has been able to do. The loss of members through inability to pay, dues has been large, and income has been correspondingly reduced, but it proved to be materially in excess of that anticipated early in the year, so that a substantial and unanticipated balance was carried forward toward the activities of 1923. PUBLICATIONS Following the example of other technical societies, and to conserve our resources, no Year Book was published in 1922. The lack of an up-to-date membership list for the use of our members was regrettable, but the saving of $5000 proved to be worth while. During the year, Volumes LXV, LXVI, and LXVII were printed and sent to members. These volumes were composed largely of the papers of 1920 and 1921, publication of which had been delayed partly through lack of funds and partly for the purpose of segregating into volumes those papers dealing with the same general subject. The segregation of papers had been suggested by a number of members who had advised that they were not primarily interested in all subjects

Jan 1, 1925

By John C. Branner

Within a couple of years I have received many inquiries in regard to the manganese-mines of Brazil. These inquiries were doubtless directed to mc because I had lived and traveled in Brazil for more than eight years, and was therefore supposed to be pretty well acquainted with its geology and mineral resources. Somewhat to my chagrin, I not only knew nothing of manganese-mines in that country, but I had never before heard of the mineral having been found here in quantity, and I did not even know in what State the mines were located. The present summer found me in Brazil again, trying to finish up some of my early geological investigations along the northeast coast, and I have used the occasion to find out something about the manganese-deposits. Very little is known of these mines, even in Brazil. While at Pernambuco I was told that they were in the distant interior of the State of Bahia. In August I reached Bahia, and there I found out, concerning the mines and their geology, enough to be worth telling for the benefit of those interested in the mining or using of this mineral. Thus far, all the manganese-ore shipped from this State has come from two mines, the principal one of which is known as the Pedras Pretas mine. This was the first mine opened, is the best developed, and was the original discovery; the second one is on an adjoining tract, and the general geology and natural conditions are about the same in both. The Pedras Pretas mine is on the Nazareth-Amargosa railway, twenty-six kilometers west of the town of Nazareth, which is on tide-water, at the head of navigation, and is reached from the city of Bahia by a small side-wheel steamer that runs across the bay of Bahia and up the Rio Jaguaripe

Jan 1, 1900

By Charles Will Wright

The application of the camera as an adjunct to topographic mapping began practically with its invention, and it has been employed with varying success since that time. With the exception of the camera to be described, the plate-camera has been universally used in this work, thus giving a projection of the area photographed on a flat surface. From such projections or photographs, by the rules of geometry and of perspective, points defining topographic features and seen from at least two camera-stations may be projected upon a ground-plane—the map.' In 1904 I employed the plate-camera for this purpose in Alaska, but found that the labor necessary to plot the maps, even in a general way, was long and tedious. In 1905 a small Eastman panoramic camera was fitted with spirit-levels, a sight-alidade and a transparent scale, introduced inside the camera to register the degree-points in the sky-line of the film-negative ; also, arrows to indicate the horizon-line. This was, on the whole, successful; but the details in the topography were not brought out in the views with sufficient clearness, aid the photographs were too small. These difficulties were overcome by obtaining a larger and more carefully constructed instrument, which was satisfactorily employed in the field during the year 1906. A panoramic view is made up of an integral number of perspective views upon flat surfaces, and logically is the most accurate and direct means to obtain an impression of a field of * Published by permission of the Director of the U. S. Geological Survey. Stanley, H. M. Photographic and Co-ordinate Surveying, Bans., xx., 740 to 766 (1891). Also, Flemer, J. ,4. Phototopographic Methods and Instruments, Report U. 8. Coast and Geodetic Survey, pt. 2, app. 10, pp. 619 to 735 (1897).

Jan 1, 1908

By Charles F. Ramseyer

The manufacture of iron and steel is one of the largest of our industries; and in point of size of single plant and equipment certainly the biggest of all industries. By the general public it is generally considered a prime example both of the marvelous technical advances achieved by modern science and engineering in the design and operation of equipment and of the efficiency of big business in the coordination of men and materials. Actually the operation of its basic processes has not changed significantly in either theory or fundamental design of equipment in the past 75 years. Though many other process industries have been born and developed, and not seldom completely revolutionized, during this period, the primary processes of making iron and steel are still carried out along the lines laid down, and in the equipment originated so long ago, by Bessemer, Siemens and Martin, and subsequently expanded to practically the modern scale by Carnegie, Schwab and Captain Bill Jones in the eighteen eighties and nineties. The application of the principles underlying the continuous counter-current physical and chemical interaction of solids, liquids and gases, which have been so successfully used in the rapid evolution of our chemical process industries, has been very largely lacking in the steel industry. In the days of the last-named giants, especially Carnegie, the steel industry made great and rapid technical progress. Carnegie's ever driving idea (as later with Ford in the production of automobiles) was the finding of new and better ways of making cheaper steel. Carnegie himself was a steelman, and so long as he dominated the industry its technical progress was rapid; and he, like Ford, was vastly successful financially as well, since his costs were continually being driven lower than those of his competitors by his advances in steelmaking technique.

Jan 1, 1935

T. R. HARRISON, Washington, D. C. (written discussion). *-Mr. Kowalke shows that a high resistance millivoltmeter is subject to smaller errors, due to change in resistance of the thermocouple to which it is attached, than is a low-resistance instrument. He uses as examples instruments having resistances of 30 and 2 ohms, respectively. At the Bureau of Standards, resistances above 300 ohms would be considered high and 30 ohms rather low. In the tests on calorized-iron thermocouples, a difference between the first and third calibrations of the couples serves to show changes due to the intermediate heat treatment and only under certain conditions would changes in calibrations due to changes in the wire be detected by ,a recalibration after 1 1/2 in. had been cut from the hot-junction end of the couple and the ends rewelded. The calibration of a couple depends only on the thermoelectric prop-erties of that part of the couple which lies within the region of non-uniform temperature, i.e., the temperature gradient; hence, so long as the temperature gradient falls along wires of similar thermoelectric properties no change in the electromotive force is produced by altering the metals of those parts of the circuit that are at uniform temperature. Usually at the cold-junction end of the circuit, copper leads, brass binding posts, manganin resistance coils, and various other materials form part of the circuit, but so long as all are at a uniform temperature (or if for each junction between unlike metals there is a similar opposing junction at the same temperature) no resultant thermoelectromotive force will be produced thereby. Likewise, if a length of several inches at the hot-junction end of the couple is at uniform temperature, it matters not if this section is unlike other parts of the couple, so long as there is good metallic connection and no source of e.m.f. other than thermoelectric is present. Cutting off part of the hot end of the couple within such a region of uni-form temperature would not alter the e.m.f. of the couple.

Jan 12, 1919

By Robert Hunt

ONE of the most serious and important economic administrative problems facing American railway authorities to-day is that of their rails, and it is one to which much thought, is being given, not only by the executive officers of the railways and the manufacturers of the steel rails, but also by State and National commissions. It is realized by many and admitted by some that the present situation is one which cannot continue. The roadways of railways must be made more secure, or the weight of rolling stock and the speed of trains must be lessened; and the desired result must be attained with the minimum outlay of money, both in expenditure on plant and in cost of operation. If the investment per mile is too large, or through the lessening of tonnage and efficiency of equipment the cost of operation is too great, the desired and demanded cheap service cannot he rendered to the public. Therefore, the weight of equipment cannot be greatly reduced, and lessening the rapidity of service would be far from satisfactory; consequently, the safety of the roadway must be secured with the least practical outlay. It is imperative that the roadbed should be properly graded, with the fewest practically possible curves; that it should have good ballast, be well drained, have good ties properly spaced, and be laid with sound rails of suitable weight, efficiently joined together, and that the whole property be carefully and intelligently cared for. My province is to treat of the sound rails. During the last few years there has been renewed interest in and discussion of that question, and I know that many rail makers not only have been and are desirous of maintaining the highest standards of manufacture which they may have attained, but have been and are seeking to better their product, in several instances devoting much time and money to that end. At the same time, they realize that the cost of any improvement in quality which they may accomplish must be kept within certain commercial bounds; and that fact is as fully understood by their patrons as by themselves, and it should be kept in mind by all who discuss the question.

Jan 2, 1914