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By F. R. Pyne

The following notes are presented in an endeavor to point out the disadvantages attending the use of chrome brick in reverberatory furnaces in which are conducted the treatment of materials of such a nature that absorption by the brick is of too great value to be wasted, and these values must be recovered, if possible, in order to prevent metal losses that can not be tolerated. Several years ago one of the large Eastern copper refineries decided to utilize basic material in place of siliceous material in the walls of their reverberatory furnaces for the treatment of very foul blister copper, as the latter rapidly corroded the siliceous linings. It was also expected that there would be less slag formation, with a consequent decrease in the cost of treatment and a reduction in the metal losses. Magnesite brick were first used, but while the corrosive action of the foul material was greatly reduced, and the amount of slag formed was very much less, the magnesite proved to be unsatisfactory in certain parts of the furnace, because of its tendency to crack and spall badly when subjected to the alternate heating and cooling that takes place in a reverberatory refining furnace. This made many repairs necessary, and consequent frequent interruption in the operation of the furnace, which, together with the high price of the magnesite brick, ran up the cost of maintenance to an unreasonable amount. It was, therefore, decided to substitute chrome brick for magnesite brick in the parts of the furnace affected. The results, as far as the reverberatory furnace was concerned, were very satisfactory. The corrosion due to the action of the foul blister was small and the amount of slag formed was no greater than when using magnesite, and the tendency to crack and spall shown by the magnesite was eliminated. Gradually the use of chrome brick was extended to all furnaces, those treating blister copper as well as those melting cathodes, and the results were so satisfactory that the siliceous roofs were replaced by roofs of chrome brick except in certain places where experience showed a more satisfactory performance on the part of the silica brick. It was immediately recognized, for both the magnesite and the chrome brick, that the metal absorption was very heavy, but it was felt that the

Jan 1, 1918

By Pierre R. Hines

These notes are based on observations made while on a recent trip through the West, for the purpose of studying the practical operation of the ball-mill. The writer takes this opportunity to express his thanks for courtesies extended at the many plants visited as well as for the valuable data received: While there are several types of ball-mill on the market, particular attention will here be given to the diaphragm type, as the open-trunnion type, especially the conical mill, has been thoroughly discussed in the Transactions. There is a prevailing impression that the ball-mill is a recent development; however, ball-mills were used extensively in Montana and other western states for crushing ores for concentration as far back as 1808. Its present prominence is due in part to its recent successful application by one of the large copper companies. Without any reference to dry grinding, the first successful ball-mill for wet crushing, which is still in operation, was built 10 years ago.l This mill, designed by Erminio Ferraris for crushing Sardinian ores for concentration, is of more than passing interest. It embodies the peripheral discharge with grates, large forged-steel balls, and the principal features of the modern ball-mill. The results approach present-day practice, the chief differences being that the mechanical construction has been improved in the modern types. Crushing Action of Ball-mill The action of the balls and the principles of crushing have been studied by several investigators.2 Their conclusions are confirmed by results obtained by the writer in experimenting with a small machine built at

Jan 1, 1918

By Fred A. Hale

Owing to the large area included in the Yellow Pine mining district, and the varied nature of its mineral deposits, a detailed geological description of the district could be covered only in an extensive monograph. This paper is intended as a description of the most prominent geologic features only with special reference to those of economic importance. The first mention of the district was in 1903 by J. E. Spurr, who briefly describes the structural geology of the Spring Mountain range. In 1906, H. F. Bain2 briefly described the Potosi mine. James J. Hillla of the United States Geological Survey, visited the district for a brief period in 1912, the result of which is an excellent reconnaissance report, covering the district in some detail but necessarily with brevity. Since that time, articles covering special features of the district have appeared in the technical press, including some by the writer, and a notable description of the Boss mine, by Adolph Knopf,4 appeared in 1915. Development of the district during the past few years has progressed so rapidly and with so many notable discoveries, particularly with reference to the rare metals, that a further description at this time may prove of interest. The writer's acquaintance with the district is based on 7 years' continuous residence in the vicinity, beginning with the spring of 1910. A. Location and Topography The Yellow Pine mining district is situated in the southwestern portion of Clark County, Nevada, about 300 miles northeast of Los Angeles, along the line of the Los Angeles & Salt Lake Railroad. The district extends from Mt. Olcott on the north to the California line on the south,

Jan 1, 1918

By C. E. Arnold

A brief description of this installation was included in a recent paper by H. Kenyon Burch.l The purpose of the present paper is to amplify Mr. Burch's description, as it is felt by the writer that the subject merits more than passing attention. In making a comparison between the common method of hoisting men in mine shafts, and elevator practice in high buildings, the former shows to great disadvantage both as regards safety measures and smoothness of operation. It is surprising that in view of the inducements offered, the step of applying the building equipment direct to the mine shaft has not been taken before, as in many respects the conditions of service are similar, and the objects to be attained are identical. Even without doing this, it is certain that safety to life and limb in the usual method of hoisting men underground can be greatly enhanced by the application to the mine hoist of some of the features of the building elevator. In the case under consideration, the elevator cage runs in a vertical, concrete-lined shaft compartment 5 ft. 11 in. by 5 ft. 6 in. (1.8 by 1.68 m.) in section and 585 ft. (178 m.) deep, while the counterweight runs in the pipe and ladder compartment of a twin shaft 102 ft. (31 m.) distant. The section of the division of this compartment occupied by the counterweight measures 2 ft. 4 1/4 in. by 3 ft. 101/2 in. (0.72 by 1.18 m.), and the counterweight is made in the form of a small cage which suffices to carry two men for the purpose of making inspections or repairs in the pipe and ladder way. The hoist is designed to carry a load of 7500 lb. (3401.94 kg.), ex-clusive of the cage, which weighs 7500 lb., at a maximum speed of 800 ft. (243 m.) per minute. It is installed in the main hoist and compressor building about 220 ft. away from the elevator shaft and is driven by a 160-hp. direct-current motor which is served by a 190-hp. motor generator set. A small direct-current generator mounted at the end of the motor generator set furnishes the current for the controller magnets, brake and fields of the hoist motor and generator. The drum, which is 72 in. (1.83 m.) in diameter, is driven through the medium of a single reduction herringbone gear. A Francke flexible coupling connects the

Jan 1, 1918

By C. F. Wang

Page I. Introduction............:.............. 395 Manchuria in General ....................... 395 Pen-hsi-hu............................ 397 Pen-hsi-hu Coal & Iron Co., Ltd................... 399 I1. organization........................... 400 III. Coal Deposit........................... 402 Location..............................402 Geology............................. 403 Coal Mining...........'.................. 404 Mining Methods........................407 Mining Cost.........................408 IV. Coal Washing Plant.......................408 V. Coking Plant..........................410 VI. Iron Deposit...........................413 Magnetite Belt.......................... 413 Origin of Deposit......................... 414 Iron Mining........................... 415 VII. Concentration Plant........................ 417 VIII. Briquetting Plant.......................... 418 IX. Blast-furnace Smelting...................... 418 iNTKODtrCTION Manchuria in General Manchuria. called the "Three Eastern Provinces" in Chinese. forms the northeastern corner of China and is bordered by Siberia on the north and northeast. and by Korea on the east. It is a land famous in Chinese annals as the place of origin of the Ching dynasty. and in more recent times it has bcen an arena for diplomatic maneuvering and commercial competition between the Russians. advancing from the north. and the Japanese from the southeast. It derives its name of "three eastern provinces" from the fact that it is divided into three provinces; Hei-

Jan 1, 1918

By E. Cortese

Phosphate occurs in many places in Egypt, in two main zones: one in Upper Egypt, along the Nile Valley, principally on the right side, and one near the Red Sea coast. In the Nile zone, the principal layers of phosphate rock are to be found: in the mountains east of Mahamid (right side of the valley); in the hills near Sibaiya, also called Sebaieh (both sides); in the hills of Agula, Hagaza and Gurn (right side); and further on, along the camel road leading from Kena to Kosseir, a few miles east of Legheita's Oasis. Following that track, after having crossed the watershed, underlain by rocks like granite, serpentine, porphyry, and diabase, one comes again to the Cretaceous formation containing considerable quantities of phosphate, at Gebel Duwi, Gebel Nakheil, and Gebel Kosseir El Kadim, not far from the coast. More to the north, in the hills near Safaga Bay (Um El Uettat El Wasif) is another rich bed of the same formation. There are reports of phosphate existing near Suez and in the Sinai peninsula, and possibly some other zones can be traced or discovered in the future. The mines are well developed on the right bank of the Nile at Sharawna (near Sebaieh Station) and along the Red Sea coast, at Safaga and near Kosseir. Prospecting work has been done at Gebel Duwi, Gebel Gurn, Agula, Hagaza, and near Mahamid. The phosphatic formation in Egypt is quite variable, not only from place to place, but even within small areas. The phosphate is all of Cretaceous age, as is proved by the fossils found in it. It is considered to belong to the Campanian or, more appropriately, to the Maestrichtian series. The principal fossils are: Alectryonia Villei Coq. sp.; Roudereia Aures-sensis Coq. sp. = R. Drui Mun. Chalm.; Trigonoarca multidentata, Newton.; Cardita libyca, Zittel; Libycoceras Ismaely, Zittel; Nautilus sp.; Ancystrodon libycum Dam.; Corax pristodontus Ag.; Lamma biauriculata Zittel sp. Above the Maestrichtian beds, we have the Danian series, unconform-ably covered by Lower Eocene beds. Under the phosphate is a grayish marly clay, and beneath this, bluish-gray scaly shales resting on the Nubian sandstone (Santonian).

Jan 1, 1918

By Dorsey Hager

The possibility of oil and gas production in Alabama his been little considered as yet. Gas and some oil have been found in northwestern Alabama, near Birmingham, in the Pennsylvanian beds, but the oil and gas possibilities in the Cretaceous beds are not generally appreciated. The recent activity of oil companies in that State has attracted much attention, and in this paper the main structural and the general strati-graphic features are described. Four favorable areas are outlined. These contain folds of major interest. There are other favorable areas which have not been mapped-l Commercial pools discovered in this area would have the advantage of being near tidewater. Mobile, Ala., on the Gulf of Mexico, would be the logical site for refineries and shipping facilities. A pipe line could readily be laid to that city from the Hatchitigbee and the Jackson areas. The logical outlet for the Geneva and the Gordon areas would be Panama City, Ha., on the Gulf of Mexico. Topography The whole of the area under consideration lies in the Gulf coastal plain and slopes gently to the southwest and west. The elevations vary from 200 to 400 ft. (60 to 121 m.) above sea level. The streams have sunk their channels into this gently sloping plain, the main drainage flowing south or southwest into the Gulf of Mexico. Between the

Jan 1, 1918

G. Sherburne Rogers (written discussion*).—Mr. Kennedy's discussion1 of Mr. Matteson's paper takes the form of a criticism of my own comments2 on this paper. Mr. Kennedy is a respected authority on matters pertaining to the salt-dome oil fields, and his characterization of my "elaborate figures" as "worthless" is sufficiently candid and comprehensive to warrant a brief reply. My 'voluminous figures" consisted simply of a rough estimate of the minimum quantity of salt in the Humble dome, and a, calculation of the volume of sea water and of the volume of saturated brine which this salt would represent. Mr. Kennedy apparently interprets my remarks as opposing the idea that so,large a volume of salt could have been deposited from sea water, for he cites the area and thickness of European salt beds; but nothing was further from my intention. Given an arm of the sea, an arid climate, and evaporation under a hot sun, it is easy to conceive the formation of almost any thickness of bedded salt. I cited the figures in connection with Harris' theory of the origin of salt domes, according to which the plugs were formed by the deposition of salt from ascending brine solutions, owing to the drop in temperature as they neared the surface. I pointed out the well known fact that the solubility of salt is only slightly affected by temperature, and that a drop of 80" C. would cause the deposition of less than one-tenth of the salt in solution; hence that more than ten times the volume of salt actually forming the plug must have been involved. If ten times the salt actually in sight be computed in terms of brine and multiplied by 50 or 60 to take into account all of the known salt domes, the resulting figure is so enormous that I am not at all so sure as Mr. Kennedy seems to be that the porous stratified rocks of eastern Texas and western Louisiana could contain or furnish so great a volume of migratory brine. Mr. Kennedy, however, does not dwell on drop in temperature as the cause of the precipitation, but contents himself with ascribing the whole process to lateral secretion. As I understand it, this implies that the connate waters and brines contained in the rocks migrated to the Gulf Coast region, and there deposited their salt at various loci of crystallization. Just what started the crystallization or what force caused the

Jan 1, 1918

By W. G. Matteson

I. Introduction...................................................... 436 (a) Extent of the Gulf Coastal Plain. (b) History of Important Gulf Coast Oil Pools. 1. Corsicans, Tex. 2. Spindletop, Tex. 3. Sour Lake, Tex. 4. Jennings, La. 5. Saratoga, Tex. 6. Batson, Tex. 7. Humble, Tex. 8. Caddo, La. 9. Vinton, La. 10. Naborton, La. 11. Red River, La. 12. Edgerly, La. 13. Goose Creek, Tex. 14. Damon Mound, Tex. 15. New Iberia, La. (c) Favorable Features of the Gulf Coast Pools. 11. General Topography and Physiography of the Gulf Coastal Plain.....440 111. General Stratigraphy of the Gulf Coastal Plain West of the 90th Meridian......................................................441 IV. Structural Types and their Characteristics.........................446 (a) hnticlinal Structure. (b) Structure of Salt Domes. 1. Domes of the Coast Prairie. 2. Domes of the Wold Region. 3. Recapitulation of Dome Structural Characteristics. V. Methods of Surveying and Prospecting............................. 454 VI. The Development of Salt Domes................- .................458 VII. Origin of Salt Domes...............4.............................461 (a) The Volcanic-plug Theory of Hager. (b) The Contemporaneous Sedimentation Theory of Norton. (c) The Theory of Upward Pressure Exerted by the Force of Growing Crystals, as Developed by Harris. VIII. Source of the Oil in the Gulf Coastal Pools.........................465 IX. Petrolific Value of the Salt Domes of the Wold Region..............467 X. Future Outlook.................................................. 467

Jan 1, 1918

By Joseph H. Taylor

The Ducktown district is in the extreme southeastern corner of Tennessee, its principal railroad point being Copperhill, on the Blue Ridge division of the Louisville & Nashville Railroad, midway between Knoxville, Tenn., and Atlanta, Ga. The ore deposits were discovered about 1849 and development work was begun in the early fifties. Only the "black copper" ores, products of secondary enrichment, from beneath the gossan outcrops and overlying the massive sulphide deposits, were then mined and smelted for their copper content. Upon their exhaustion, attention was directed to the treatment of the pyritic ore remaining, resulting in the devising of a process consisting of open-heap roasting, followed by blast-furnace smelting, which was practised until 1903, when semi-pyritic smelting was adopted. In 1908, the companies operating in the district, on account of litigation brought about by alleged smoke damage to forests and vegetation in the adjoining counties of Georgia, were compelled to erect enormous acid plants to prevent the escape of the sulphur dioxide produced in the smelting operations. The utilization of this sulphur dioxide in the manufacture of sulphuric acid as a byproduct has added to the revenues of the companies, and at the same time has furnished a valuable source of supply of sulphuric acid to the fertilizer trade of the South, and more recently to the manufacturers of eyplosives for use in the production of war munitions. The steadily increasing demand for sulphuric acid for the manufacture of fertilizers and explosives, together with the decreasing imports of pyrites, from which the acid is generally produced, now makes it imperative that greatly extended resources of pyrite be developed. While the Ducktown deposits do not predominate in pyrite, they do contain an inexhaustible supply of pyrrhotite, admixed with pyrite, which can be satisfactorily employed to supplement or substitute for pyrite in acid making.

Jan 1, 1918

By Charles T. Van Winkle

Until the advent of the porphyry coppers and the introduction of flotation which soon followed, crushing and grinding for many years proceeded along somewhat stereotyped lines, without important alteration in type of machinery. For the finer crushing and grinding, stamps, rolls, and various patterns of Huntington and Chilean mills were in general use. Ball-mills were in use abroad, but owing to their small capacity and the high cost of screens and steel, they never obtained much footing in the United States. Tube-mills were first introduced into the crushing departments of cyanide plants when it was found that for crushing finer than 30-mesh other types of crushing machinery were not efficient. In order to crush with one pass, these mills were made 18 to 22 ft. (5.5 to 6.7 m.) in length. Pebbles were used as a grinding medium and the mills were lined with either silex blocks or fragments of quartz or flint pebbles set in cement. While the cylindrical tube pebble-mill had been used to some extent in small installations of concentration mills, the first instance of its use on a large scale was at the concentrating plant of the Miami Copper Co., where 8-ft. by 22-in. (2.5-m. by 55.9-cm.) Hardinge mills were tried out against Chileans. The results of these experiments led to the gradual replacement of the Chilean by the Hardinge mill. Robert Franke published an article' describing the work done, comparing the two types of mills. At the same time, according to Franke, a test was run using a 6-ft. (1.8-m.) Hardinge ball-mill as a substitute for rolls for intermediate crushing on 1/2-in. material. According to Franke, this mill was soon discarded, since it was found that to obtain the desired product the mill must be limited in capacity. The Miami Copper Co. made no test with other types of ball- or pebble-mills. Following this example, others installed the conical type; and when the Inspiration Consolidated Copper Co. decided to build a concentrator, it adopted the conical mill. As the requirements for mills would be very large, it purchased manufacturing rights in the State of Arizona from the

Jan 1, 1918

By L. P. Teas

The main facts brought out by the study of the blende-bearing ores examined are as follows: 1. Chalcopyrite as minute triangular or rectangular dots, or as

Jan 1, 1918

By G. S. Rice

With so tremendous a subject, an attempted review of the coal situation of the world in a short talk must necessarily be of a sketchy character. It is hardly necessary to tell a body of engineers that had it not been for nature's gift of coal the material side of modern civilization would never have reached its present status. On the other side, it is regrettable that it was a byproduct of coal, T. N. T., which made possible Germany's initial success in this war, because that country had an enormous development of manufacturing plants that could be immediately utilized to make this destructive agent: One sometimes hears the casual remark that when the coal of the world is exhausted we shall use electricity; but, of course, electricity is ordinarily only a means of transforming and transmitting energy derived from fuel or water power, and chiefly from coal. It is true, we have much undeveloped water power, but it is more or less remote from 'the, centers of industry; and when all shall have been developed it will not begin to supply the power requirements of the world. It is, however, reasonable to expect that before the world's supply of coal shall be exhausted, methods will have been discovered of harnessing other forces of nature, such as the tides, or the energy emanating from the sun. Petroleum and natural gas naturally come to mind, but the days of both, as fuel, appear to be numbered, although the products of petroleum, if economically used, doubtless will be available for internal-combustion engines, automobiles, trucks, and boats for a long time, provided the reckless use of crude petroleum as an ordinary fuel is stopped. The products of petroleum are too valuable to mankind for such waste to be permitted. The civilization of the world, therefore, appears to rest, and, so far as can be seen, will indefinitely continue to rest, upon coal. COal Resources of the World According to the compilation made by the geologists of the principal countries for the 12th International Geologic Congress, held in Canada

Jan 1, 1918

By E. E. Bach

The administration of industrial organization today embraces more than the cost of production and selling prices. Competition is deeper seated than mechanical devices, overhead charges, and a shrewd manipulation of the markets. Despite the " down-to-the-minute " equipment and the "last word in organization," it is quite evident that "capacity production" will be an unknown quantity until the workman is considered as a producer, in relation to his home, as he is now considered in relation to industry. Whether or not a man shall do an honest day's work is as much a psychological condition as it is a matter of physical strength or skill. His attitude toward his work each morning is determined, to a large degree, by the environment of his home. Whether this attitude, good or bad, obtains the day through will depend entirely upon the one fact as to whether the corporation which employs him does or does not differentiate between the mechanical factor and the human factor in industry. To be more specific, sociological work, under whatever name, should be of such a character as to influence the life of a workman in such a manner as to establish a cooperative interest in his work, foster within him a spirit of contentment in his home, lead him so to employ his leisure time that he will not lower his efficiency as a workman, destroy his domestic happiness, or endanger his standing in the community as a citizen. While no fixed rules of procedure can well be formulated for the development of the work, yet definite lines of activities will readily present themselves as applicable to the individual needs of a community. This is especially true where community influences and agencies pertaining to general welfare are easily correlated. Any definite work attempted must be determined by the type of the

Jan 1, 1918

By J. O. Lewis, Carl H. Beal

Introduction ............................... 492 Theories Relating to the Recovery of Oil.................. 493 Methods Commonly Employed for the Estimation of Future Production..... 495 Saturation Method........................... 495 Production Curve Method....................... 496 Production per Acre Method.....................: 496 Appraisal Curves.............................. 498 Derivation and Construction...................... 498 Comparison of Appraisal Curves of the Osage and Nowata Fields...... 505 Use of Appraisal Curves........................ 506 Accuracy of the Apprais?l Curves and Their Sources of Error........ 508 Relation Between Future Productions of Wells of Equal Output....... 510 Use of Appraisal Curves for the Derivation of Generalized Future Decline Curves. 513 Theory of Generalized Curves Showing the Decline in Production...... 513 Suggested Methods for Making Closer Estimates.............. 517 Use of Logarithmic Coordinate Paper.................... 518 Summary................................ 520 Introduction Oil wells usually reach their maximum daily output shortly after they are completed. From that time they decline in production, the rapidity of decline depending on the output of the wells and on other factork governing their productivity. The production curve of a well shows the amount of oil produced per unit of time for several consecutive periods; if the conditions affecting the rate of production are not changed by outside influences, the curve will be fairly regular, and, if projected, will furnish useful knowledge as to the future production of the well. By the aid of this knowledge the value of a property maybe judged, and proper depletion and depreciation charges may be made on' the books of the

Jan 1, 1918

By A. M. Nicholas

WheN attempting to lift mill pulp containing a considerable percentage of wolframite, in an ordinary bucket elevator, difficulty was encountered from the tendency of the tungsten minerals to settle, on account of their high specific gravity. Lifts not exceeding 20 ft. (6 m.) could be accomplished without particular difficulty, because there was insufficient time for consolidation of the heavy minerals in the bottom of the bucket; but with higher lifts, the heavy tungsten minerals would settle so solidly that when the bucket turned over at the top of the elevator the contents could be only partially dumped. In this case it was necessary to lift the material a distance of 34 ft. (10m.); hence some means had to be adopted to prevent settling, at least to such an extent that the material could be dumped from the buckets. To reduce the carrying time to a sufficient extent would have required a belt speed of 475 ft. (144.7 m.) per minute, which was not feasible. It was decided to try, by vibrating the belt about midway of its span, to keep the material sufficiently agitated during elevation to prevent settling. Underneath the rising side of the belt was placed a 12-in. (30.48-cm.) idler pulley, 18 ft. (5.5 m.) up in the total lift of 34 ft. The idler pulley was set eccentric by % in. (19 mm.) and it was hoped that the vibration thus imparted to the belt, running at a speed of 280 ft. (85 m.) per minute, would prevent settling in the buckets. It was found that the pressure of the belt on the idler, due to the small inclination of the elevator, was not sufficient to overcome sliding on the idler, and the agitation was insufficient to accomplish the desired purpose. The idler was then connected to the drive shaft of the elevator through an intermediate pulley, gearing down to a speed of 20 r.p.m., so that a positive vibration was imparted to the belt; this imparted enough motion to the belt to prevent settling and the contents of buckets dumped satisfactorily. Protecting Elevator Belts When elevating, from the crusher, a rock which was very sharp and abrasive, considerable difficulty arose from cutting of the belt under-

Jan 1, 1918

By W. P. Frey

The briquet plant of the Lehigh Coal and Navigation Co., at Lansford, Pa., has previously been referred to.' It has passed the stage of experiment and now rests on a foundation practically and financially sound. The purpose of this' paper is to explain how success has been attained, and to set standards for the development of hard-coal briquetting which may eliminate future failures. All the conclusions are based on actual results, avoiding speculation and theory. Up to three years ago, the L. C. & N. Co. used coal-tar pitch as a binder in making hard-coal briquets. The plant operated with a monthly output of 300 to 600 tons and was unable to meet its own expenses. Naturally, no one was satisfied, especially as the ideals of a smokeless briquet were still unrealized. Then came the Dutch oil process, introduced in this country by the General Briquetting Co. of New York. This process uses as binder a small percentage of heavy residue of petroleum, which, being liquid, permits great economy of handling; it also did away with the most objectionable fumes of the former briquets. This oil2 is not absolutely smokeless; heating the fresh fuel to red heat liberates some low-volatile hydrocarbons, yielding a white smoke which is not objectionable. On the other hand, this oil adds to the briquet about 7 per cent. of volatile matter, giving the product a heating capacity equal to that of the best free-burning anthracite coal. The average silt used in the manufacture of these boulets averages 16.5 per cent. chemical ash, corresponding to 12,000 B.t.u. per pound of coal. The Hydrolene used as binder runs about 17,500 B.t.u. per pound, and approximately 7 per cent. of it enters into the mixture, hence 12,000 X 0.93..........................11,160 B.t.n. 17,500 X 0.07.......................... 1,125 B.t.u. Total.....................................12,385 B.t.u. per pound of briquets

Jan 1, 1918

By Hugh R. Van Wagenen, Allen H. Rogers

There are few natural monopolies comparable with the nitrate industry. Perhaps the only other one is, curiously enough, also an essentia1 fertilizer material, viz., potash, of which the Germans have heretofore held practically a monopoly due to the existence in their territory of the most important known deposits of potash salts. And although nitrates in minute amounts are found in many desert regions, the only deposits capable of being worked commercially exist in Chile. Combined nitrogen in the oxidized form is an essential for plant life. Nature provides it mainly through the agency of nitrogen-fixing bacteria. But where lands are cropped artificially this supply is too small, and gradually the nitrogen supply becomes exhausted. In order to continue farming, it is necessary to furnish a supply of nitrogenous plant food, and this is done by putting on various substances containing combined nitrogen. These consist of various animal wastes, ammonium sulphate, the ammonia of which is obtained in the destructive distillation of coal, and Chile saltpeter. The latter is immediately available as a plant food, the nitrogen being in the required form. The other substances must oxidize before they are available. Resides its use as a fertilizer, Chile saltpeter is the source from which the bulk of the nitric acid of commerce is derived. The use of nitric acid in the manufacture of almost all modern explosives is, of course, well known. Importance of the Nitrate Industry Chilean nitrate, the existence of which was first mentioned in 1809, is said to have been first exported in 1830. Only a few thousand tons per annum were exported for some years, but the amount gradually increased until, in 1879, when the Chile-Peruvian war began, the export amounted to about 300,000 tons. This nitrate was largely produced from the Province of Tarapaca, until then, Peruvian territory. By the terms of peace with Peru in 1884, this province, as well as Tacna, became Chilean. The Bolivian Province of Antofagasta was also acquired as a result of this war, and thus Chile, with the deposits in her own territory, acquired control of the whole supply of nitrate. At the present time, exports are approximately 3,000,000 metric tons per annum,. having a

Jan 1, 1918

By Frank B. Gilbreth

The problem of the crippled soldier in industry is not a problem of war work only; it is a problem of industrial development. As individuals, each one of you is seeking to provide our maimed heroes with such teaching as will render them, in the shortest possible amount of time, productive and satisfied members of the community. As individuals you are interested in the organizations that are preparing to receive these men, to train them and to place them at that work for which they are best fitted. As an organization, it is now your duty to take up the industrial end of the problem, to investigate existing conditions in the industries, to discover where the opportunities for employment lie, and so readjust industrial practice that the cripples may be utilized to their own and the community's good with the least shock to themselves or to the industries, and with the greatest amount of permanent benefit to all concerned. We have divided industrial opportunities suitable for cripples, roughly, into three classes. First, such as already exist in the industries, which can be set aside for cripples only, present occupants being transferred to other work for which they can be fitted but which is not suitable for cripple work; second, opportunities in the industrial world that, through changes in the working equipment or tools, or through appliances attached to the cripple himself, can make the cripple a competitor of the sound worker; third, opportunities not existing at present in the industries, but which could be introduced for the good of the community without placing the cripples into competition with any existing class of workers. As typical of the first type of occupations for cripples, we have mentioned that of store-keeper, of the second type that of typist,2 and of the third type that of dental nurse.3 The last occupation can be so arranged as to take from the overworked dentist the work of cleaning teeth; and

Jan 1, 1918

By E. P. Humphrey

The Lehigh Valley Coal Co. finished the rebuilding of its Drifton No. 2 breaker at Drifton, Pa., in the summer of 1917. The new construction comprises an addition and the complete remodeling of the old breaker. It is of interest to note that the old structure was the first iron breaker erected in the anthracite region. The Old Breaker This old breaker was built by the Cross Creek Coal Co., under the direction of the late Eckley B. Coxe, in 1888-89, and was fully described by him in the Transactions1. The columns were cast iron, 8, 10 and 12 in. square. The floors and partitions in pockets were cast-iron ribbed plates. The struts were cast iron of "H" section; the other members were of structural iron either rolled I-beams or built-up sections. The sizes of the rolled beams varied from 6 to 20 in. deep, while the built-up sections, made of plates and angles, varied from 6 to 63 in. in depth, so that there apparently was no rule to determine the type of section used. In the remodeling of the old structure, practically everything was taken down excepting the columns and roof, and such beams as were necessary for temporary construction purposes, and, therefore, a close inspection of the old structural members could be made and the effect of the acid water on them could be noted. The cast-iron members were but slightly attacked by the water, while the wrought-iron beams, in the wet places, were corroded almost to failure. The following are analyses of cast-iron, wrought-iron, and structural-steel samples taken from the old and the new structure.

Jan 1, 1918