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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

By R. E. Hobart

The development of the Hauto power plant and the claims made by various engineers that electricity was more economical than steam for power purposes in and about the mines, led the Lehigh Coal and Navigation Co., in 1911, to conduct a test to ascertain the consumption of power used by a large steam hoisting engine. The question being one on which no reliable information could be found, and the opinion of various engineers differing to such an extent, it was decided that a test under actual operating conditions was necessary. This was arranged for at one of the collieries. The engine selected was 2 30 by 60-in. (76.2 by 152.4-cm.) piston-valve engine of modern type, and comparatively new. The boiler plant from which the hoist received its power was about 600 ft. (182 m.) from the engine, the latter being fed by a 10-in. (25.4-cm.) steam line insulated with magnesia pipe covering. Two batteries of the boiler plant, aggregating 1200 hp., were cut off and fed into a separate steam line leading direct to the hoist engine. Steam auxiliaries, consisting of feed-water pump and blowers, were fed by the boilers in test, and their consumption charged against the hoist. A barrel weighing device was installed, as it was felt that this would be the most accurate way of determining the consumption of water. The fuel, No. 3 buckwheat, was carefully weighed, and every precaution was taken to make the test accurate in every particular. The test was run for 1 week, or a total of 168 hr. A record was kept of the number of trips hoisted or lowered, and continuous indicator cards were taken. One particular set of cards was taken with the hoist operating balanced, and also with the hoist operating with no counterweight other than the empty cage, the coal in the car being weighed. The speed of the hoist was taken by means of a graphic recording instrument which registered the number of revolutions every 5 sec. From this record, speed-time curves were plotted.

Jan 1, 1918

By Thomas T. Read

The cost of labor turnover in industry is so large as to justify the adoption of almost any means to bring about its reduction. Intensive study has shown that faulty methods of hiring and discharging men is the most important factor in labor turnover. Complete control over hiring and discharging by the foreman is a relic of outgrown industrial conditions; centralized hiring permits this work to be put on a scientific basis and also does away with many serious evils that cannot, otherwise be reached. Centralized hiring does not impair the authority of the foreman; he hires his men from the employment office and discharges them back to it, instead of from and to the street. The employment manager, being a direct representative of the employer, tends to restore the former relation of direct intercourse between employee and employer that was helpful in avoiding friction between them. Being a specialist,, he is able to bring special knowledge and skill to bear upon the task of selling employment in his concern to desirable workmen; he is also able to give the foreign workman the special attention he requires. Employment managers have been used for the past few years by a number of large organizations, a few of which are engaged in the mining and rnetallurgical industries. They have invariably reduced labor turnover, in some cases to as little as one-tenth of what it had been. So great a reduction is due in part to other changes made in the light of the data made available by scientific study of the labor problem. In my former paper on personnel work' I advocated the more general use of the employment manager in mining and metallurgical enterprises as a means of reducing labor turnover. The form of organization recommended seems not be to understood by all, and I have requested the privilege of explaining it at greater length, since it is perhaps the most important factor of all in personnel work, and has a vital influence on the cost sheet of every industrial enterprise.

Jan 1, 1918

By Otto Wartenweiler

After the phenomenal development of the new mine, the United Eastern Mining Co., with Mr. Frank A. Keith as President, decided to install a reduction plant. The character of the ore, closely resembling the product of other mines in the district, did not offer any particular metallurgical problems, since these neighboring mines had been operating milling plants very successfully for several years. Thus, with the general metallurgical treatment fairly well-defined, the matter of next importance was to design and construct a plant as economically as possible, that would give the best results obtainable. The ore consists of a mixture of calcite and quartz in about equal quantities, with some decomposed andesite, while the average value of mill feed was calculated to be $20 or more in gold, no silver being present. The tonnage to be treated at the start was fixed at 200 tons, but, in view of the favorable condition of the mine, it was considered advisable to arrange facilities for increasing the capacity to 400 tons. While it is best in some cases to adopt a distinct independent unit system where future enlargement is contemplated, in this instance the plans worked out differently. Summarized, the treatment adopted consists of coarse crushing, coarse grinding, fine grinding and cyanidation. For coarse crushing the selection of the No. 6 size gyratory crusher was governed not so much by its capacity as by the size of the feed openings to receive the run-of-mine material, which was too coarse for a No. 5 crusher. TO accomplish the coarse grinding to best advantage, a careful comparison was made between the modern steel ball-mill—the last word in crushing and grinding—and one of its older, and, at that time better-established, competitors, the rolls. The following conclusion was reached: While it is possible that for the sized plant under consideration the cost of operating rolls might be a little cheaper, it is preferable to use ball-mills because a simpler arrangement is possible, and because the handling of ball-mills is preferred by the operator. A marked departure was introduced for fine grinding. Instead of the long type of tube-mill, using pebbles, a mill of similar design was selected, but of much shorter length, using small cast-steel balls as grinding medium. For cyanidation, the Dorr continuous countercurrent process was

Jan 1, 1918

By H. C. George

The Wisconsin Zinc District, or the Upper Mississippi Lead and Zinc District as it is often called, lies in the southwestern corner of Wisconsin, in Grant, Iowa and Lafayette Counties, and it includes adjoining parts of Illinois and Iowa. The district is about 70 miles long, north and south, and about 40 miles wide, east and west. It lies wholly within what is geologically known as the non-glaciated area of the Upper Mississippi Valley. HISTORY OF THE DISTRICT The district was first opened up as a lead producer in 1822. From this time until 1860, about 205,000 tons of cog lead (galena) and washed lead (galena) was produced from shallow crevices and openings. From 1860 to 1900, about 74,500 tons was produced, and since that time, from 5000 to 7000 tons has been produced annually. Since 1900, most of the lead concentrate produced has been as a byproduct of the zinc mines. The first zinc ores were mined about 1862. These were the carbonate ores, locally known as "drybone." Very little zinc blende was mined in the district, previous to 1875. The zinc blende ores mined from 1875 to 1900 were mostly of the high-grade, hand-cobbed, sheet-ore class, which usually contained from 45 to 60 per cent. metallic zinc Such mines as the "Sallie Waters," "Quinlin," 'Lead Mine," "Benton Blende," and "Ida Blende," located near Benton, Wis., were mines which produced ores of this type, during this period. The mines located at Highland, the "Coker Mine" located at Livingston, Wis., and the "Opencut Mine" located at Shullsburg, Wis., were mines that were heavy zinc carbonate producers, previous to 1900. The production of zinc ores in the district from 1862 to 1890 was about 283,500 tons, mostly zinc carbonate, with a probable average metallic zinc content of 30 per cent. From 1890 to 1903, the production

Jan 1, 1918

By F. C. Stanford

The work of an engineer is to direct natural forces so that the: bring about the results that he wishes to secure. Heretofore he ha concerned himself chiefly with physical forces and inanimate objects until he has secured a truly marvelous degree of control over them The great problem of the present age is to secure a like degree of know1 edge and control of the human factor. Progress has already been made along this line, but it is only a beginning. Wilhelm Ostwald says tha scientific knowledge enables a man to be a true prophet; but it must be remembered that a good many people do not seem to be able to main tain a high average in prophecy. In short, 'the average of knowledge is not equal to the average needs of the present time, but continually fails to keep pace with it. It has been aptly said that the really essentia need of the period is for more brains; if we only had sufficient knowledg and sagacity we could not only solve all difficulties, but prevent then from arising. This generalization holds good for an industrial organization. Th most vital need of the management is for more brains. The logica course for an engineer in charge of an industrial organization is, therefore to direct whatever forces may be at his command toward the development training, and guiding of all the brains in his organization. This is easie said than done, for it involves the carrying on toward two objective: the maximum of productive work, and the development of the individual who perform it. This is essentially like the rebuilding and enlarging of plant, keeping it in full operation the while. On the other hand, if th aim is merely for maximum production from an organization, withou offering opportunity for development, the final outcome will necessari be like that of a plant that is driven at full capacity without stoppin for repairs or improvements; it eventually becomes so run down th either a complete rebuilding is necessary or else it has to be abandone

Jan 1, 1918

By M. R. Daly

In a recent paper on Geologic Structure in the Cushing Oil and Gas Field, Oklahoma,l Carl H. Beal has pointed out some interesting peculiarities in the distribution of the hydrocarbons and the disposition of the "planes of separation" between the oil and the water (water surfaces). Mr. Beal's principal statements on this matter may be, summarized as follows: I. In every important dome in the Cushing field, which has not been complicated by folding along its sides, the oil area in each of the three oil and gas sands studied (Layton, Wheeler and Bartlesville) apparently extends farther down on the long axis of the dome than it does on the steeper sides. The result is that water is encountered at a lesser depth below datum plane (sea level) on the steep sides of the dome than along the ends where the beds are more gently tilted. II. In the Layton and Wheeler sands (to which the detailed study of water surfaces has been almost entirely confined), the water surface is not level, but dips at a gentle angle (maximum dip 100 ft. to the mile) away from the center of the structure. This inclination existed prior to development, and it has been rendered greater by the rapid extraction of oil and gas. To these statements, the following observations are added: The dominant structural feature in the Cushing field is a broad north and south anticlinal fold, along whose axis the domes are distributed (Fig. 1, p. 897), and the more important oil areas in each sand lie on the west side of the field. In many cases, gas has been forced to the east side of the structure, sometimes as far as the water line. From the distribution of the oil and gas bodies, Mr. Beal concludes that the hydrocarbons in this region probably migrated from the west or the northwest. It seems as if these different features would be susceptible of some

Jan 1, 1918

By L. E. Wemple

Previous to 1915, zinc refining had not become a general practice among the zinc smelters in the United States. Such refining as had been carried on was confined chiefly to remelting very high-leaded zinc, such as third-draw metal from the retort furnaces, and slab dross, and hard spelter from galvanizing pots. In this remelting operation, the lead and iron were settled out and the refined spelter obtained graded fifth class, ie., Prime Western. Owing to the presence of lead in most zinc ores, the bulk of the spelter produced by direct smelting is of this Prime Western grade. Careful selection of ores of low lead content gave purer grades of spelter, z.e., Brass Special and Intermediate; and smelters which could secure ores carrying practically no lead produced high-grade spelter. Thus, in general, the grade of spelter produced by any smelter was predetermined by the purity of the ore it could obtain. The needs of the warring nations of Europe for enormous quantities of cartridge and other high-grade brass resulted in such a demand for the purer grades of spelter that the available supply of lead-free and low-lead ores could not produce the quantity required. Prime Western grades went begging, so to speak, while high grades sold at times from 5 to 15 c. per pound over the Prime Western market. The great demand, coupled with the wide market margin, which permitted the inherent costs and losses, resulted in the conversion of the lower grades into higher grades by processes of refining. These conditions also accentuated the development and size of the electrolytic plants, which were being worked out at the time this increased demand for pure grade of metal occurred. The electrolytic process, where available, produces a higher grade of spelter from impure ores than does the fire process; a large portion of those impurities in the ore, which by the distillation process would be carried into the spelter, are removed in the leaching of the ores and the purification of the solutions. The refining process, adopted at a number of smelters for the purpose of converting low-grade spelter into grades suitable for bras4 was that of redistillation.

Jan 1, 1918

By Max Mason

In 1923 a Western mining company was experimenting with the device of an inventor designed to locate buried ores by radio. Because the progress was slow and the results were confusing, the company began to doubt the usefulness of the method and invited me to review the whole question of the application of physics to ore detection. I was fortunate in securing the cooperation of several physicists who had worked with me during the war on the problem of submarine detection. This group has been increased and has been studying the problem of physical exploration for ores since that time. It was evident that the problem is a big one, with many angles of approach. Its general features may be set down, in rough outline, as follows: The soils, rocks and ores hidden beneath the surface differ one from another in many respects. These differences may be made to furnish a clew for the physicists working from the surface. To bring these differences into action the physicist creates some kind of an effect which penetrates into the ground and is distorted and reflected when it meets boundaries between different sorts of underground structure. In other words, he sends a message down, and the rocks and ore send back signals in reply. In picturing this process, we should not regard the ground as dense and impenetrable. The kind of messages used pass through the earth about as readily as a sound wave travels the air. If, then, the fundamental procedure is to shout down questions in the hope that an orebody will hear and answer back to us, it is clear that a large part of the expert's study must relate to the kind of questions best suited to the temperament and intelligence of orebodies. It will be easier for the ore to reply to some of our questions than to others, and it is for us to find the right questions. In certain cases, we are spared the necessity of using a messenger, because nature has already provided one. For example, we already have a terrestrial magnetic field which automatically and continually conveys messages from underneath. We also have available the earth's gravitational field which furnishes us

Jan 1, 1929

THE New York Petroleum Club has elected the following officers for the current year: Chairman, William B. Heroy; vice-chairmen, Edwin B. Hopkins, Warren. A. Sinsheimer; secretary, A. C. Hunter. This is the local section of the Petroleum Division. It holds monthly lunch-eons, usually in the rooms of the Railway Club.

Jan 3, 1927

By Frederic E. Carter

The gold, silver, copper alloys have been the subject of several fairly complete investigations by Janecke, Sterner-Rainer&apos; and others, and indeed it would seem as if almost too much labor had been expended on them when one thinks of the numerous other ternary alloys calling for more light; however, the combinations of the three metals are actually so widely used in jewelry that they merit perhaps the work done on them. There are a few properties of importance and interest not treated by the authors mentioned which the writer investigated some little time ago, and therefore he has ventured to put on record the results of some of his tests made at that time. He has chosen, as being the two series of most importance to the jeweler, only the 14 and 18-kt. golds, so the subjcct is by no means so inclusive as that previously treated. As statecl, this paper is merely a record of tests made in a practical manner on two itucbful series of alloys, and is not at all a critical study of their properties. 14-Karat Alloys These alloys are important because they arc the most generally II,<(S(I in 14-kt, jewelry; by changing thc proportions of silvcbr and copper Iliero are obtained all shades of color from the green of the alloy contiainng gold and silver but no copper, to the red of the alloy containing gold ;,, copper but no silver. Many 14-kt. gold alloys are made with the sdditjon of zinc to the three metals mentioned here; the added lnetnl does not appreciably alter the color of the alloy nor has it, in general, much effect on the working properties; it may, however, prove useful as ynrt of thc zinc added may act as a deoxidizer and render the alloy free of ga,s. 11, iy not a necessary addition because with proper precautiolls :111 I lie 14-At. gold alloys containing only silver and copper in :tcltlitiotl to the gold ran be made free of gas and capable of being cold rolled without craci The alloys in which approximately equal quuntiticrs of silver ami