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By Edward Thomas

THE late George S. Rice was active in the investigation of bumps, particularly in the last ten years of his career as chief mining engineer of the U. S. Bureau of Mines. Since most of his investigation was carried out in Great Britain, continental Europe, and-to a lesser extent-Canada, his thinking on prevention was influenced considerably by the experience of those countries. It is not surprising, therefore, that when he was called upon a few years before his retirement to investigate bumps in the U. S. and suggest ways to prevent them, he turned to longwall mining. A longwall method had been most successful in combating the bump hazard in mining coal under deep cover, especially in Great Britain, but the prevailing method there at the time was advancing longwall mining, which he knew was uneconomical under U. S. mining conditions. For this reason he proposed a modified retreating longwall system that he believed included the best features of the advancing method. As brought out by Rice,1 if the cover is 2000 ft and 50 pct of the coal is extracted, the static load on the remaining pillars will be about 4000 psi, which exceeds the ultimate crushing strength2 in most instances. If the pillar coal is overloaded before a pillar line is established, then the abutment zone preceding a line of extraction is no place to split pillars or extract them by any method other than an open-end system. Rice therefore advocated open-end mining, preferably by longwall, but he was willing to compromise with long-face mining if the longwall method was not acceptable.

Jan 8, 1958

By Marius R. Campbell

VArIoUs classes of coals are recognized in this country at the present time. These classes depend largely upon physical characteristics rather than upon chemical composition, and consequently they cannot be accurately defined. The divisions into anthracite, semi-anthracite and semi-bituminons are fairly satisfactory; but the term bituminous embraces so large a variety of coal that it is of little value, and the term lignite is so loosely applied that it has little or no place in a scientific classification.

Jan 1, 1906

By C. M. Kleeman

All mines have a finite life and the time comes when the ore is depleted, or it has become uneconomical, or for some other reason which may be peculiar to that particular mine, it must be shut down. The operation at that point of time still has some assets such as mining and milling equipment, workshops, and in the case of a gold mine, an unknown quantity of gold which has been trapped in the treatment plant. Recovering this gold can be done at small cost and can be extremely profitable. Recovery of these hidden assets requires a good knowledge of the treatment plant, i. e. , as say values of heads, tails, and of the products produced; and if mercury for amalgamation was used, where? A careful study of available plant records can be extremely valuable in forming a working plan for adequate recovery. In the following paragraphs the various unit operations and equipment where gold can collect are described and suggestions made for its recovery. Subsequently, a case history will be given for dismantling a gold plant which had a complex flowsheet and which had been in operation for many years. Looking for trapped gold in a crushing section would invariably not be worthwhile since crushing is normally a dry process and there would be few areas where free gold could collect. In the milling section, however, many areas can literally become small gold mines in themselves. Material in the bottoms of grinding mill scoop boxes can be high-grade, and even the scale on the sides of the boxes should be scraped off and collected. Mill liners should be removed and all scale, rust, and residue collected. Residue in the bottoms of rake or spiral classifiers, if they have been used, should be removed as should the scale and rust on the sides of pump sumps, launders, etc. The following procedures should be used to extract gold from these collected materials. All steel (ball scats) should be removed, screened out, and reserved. Fine material should be placed in an amalgam barrel, water added and ground with the amalgamation tailings being sampled and assayed. If high-grade, tails should be reserved; if not, discarded. The coarse material that was screened out should be placed in a heap, regularly sprayed with water and allowed to rust. After several months this material should be screened again and the fines amalgamated.

Jan 1, 1981

ZAY JEFFRIES (written discussion*).-I have read with much interest Mr. Ruder's discussion of Professor Howe's paper, "The Supposed Reversal of Inheritance of Ferrite Grain Size from that of Austenite." I am yet of the opinion that my first explanation' of Mr. Ruder's samples is substantially correct. In that explanation I did not intend, however, to convey the impression that "reversed inheritance" was the general rule nor even of common occurrence but rather that." Non-inheritance" was the general rule. Mr. Ruder suggests that a " perfectly formed" grain is an indication of inheritance. The grains in my Fig. 52 are perfectly formed and in fact more nearly equiaxed than those in Mr. Ruder's Fig: C,3 yet the grains in the former are known not to be inherited but to have been formed by the partitioning of larger austenite grains. On close examination of Mr. Ruder's Fig. C the very shapes of the grain suggest partitioning. Again, the grain size (25 to 30 grains per square millimeter) is at least 10 or- more likely 20 times smaller than might be expected of the austenite from which these grains were .formed under the given time and temperature conditions. Mr. Ruder's newer results on electrolytic and Armco iron are most interesting and instructive. His results fit in. nicely with my conclusions 5, 6 and 10.4 His photographs, however, indicate that the thickness of the pieces of sheet metal are such that abnormal grain growth is promoted. He indicates that equilibrium grain size after heating to 950° C., with furnace cooling, is about the same as his Fig. 1, above. I estimate this to be approximately one-half -grain per square millimeter, or 40 times as large as I have obtained with the same material (Armco iron) after heating Y4-in. bars to 1300° C. for 2 hr. and cooling in the furnace. The effect of thickness of sample on grain size is one which needs more attention.

Jan 3, 1918

By R. B. Toombs

The national and international importance of Canada's minerals and metals producing industry is reported. The growth of the Canadian industry is traced from 1945, through the period of rapid development of the early 1950's, to the consolidation and expansion activities of the late 1950's and early 1960's. Mineral production in Canada during 1963-including steel, nonferrous metals, and fuels -is reported. It is estimated that by 1970 the Canadian industry will produce $3.9 billion worth of metals, nonmetals, and fuels.

Jan 8, 1964

By Rosewell H. Johnson

Discussion of the paper of ROSWELL H. JOHNSON, presented it the San Francisco meeting, September, 1915, And printed in Bulletin No. 102, June, 1915, pp. 1291 to 1294. WILLIAM A. WILLIAMS, San. Francisco, CaI.-A sliding. scale of royalties was proposed to the Department of the Interior in connection with the fixing of royalties to be charged upon oil leases made on the Osage Reservation in Oklahoma. The possibility of evasion and difficulty of enforcement required close inspection to satisfy all interests, particularly in connection with the exemption from royalty on oil to equal maintenance and interest on the junk. Mr. Johnson discusses the block method, the period method, and the cumulative method, and favors the adoption of the cumulative method with a proviso that the wells should be permitted to be pumped until the gross income is as low as the maintenance cost, which would mean exemption from royalty on the smallest wells. He recommends that depth be the variable factor upon which the sliding royalty is based and suggests that on partially developed territory in the Osage, the royalty be one-sixth for oil wells averaging less than 2,000 ft. in depth, one-eighth for wells from 2,000 to 3,000 ft., and one-twelfth above 3,000 ft.; for the rest of the Osage he suggests one-eighth above 2,800 ft. and one-twelfth below that depth. The net result, if Mr. Johnson's suggestions had been accepted in the Osage, would have been to reduce the then existing rate of royalty and considerably increase the cost of administration. The difficulties in determining the size of wells to be exempt and the possibility of obtaining oil at different depths in the same well might lead to complications which are avoided by charging a flat royalty as now universally charged throughout the United States. It is not uncommon to reduce the royalty when the production of the wells becomes unprofitable at an existing rate of royalty, accomplishing very much the same results as Mr. Johnson has attempted to accomplish by the cumulative royalties, and probably in a manner far more satisfactory to the operator and the lessor. A. C. MCLAUGHLIN, San Francisco, Cal.-The net revenue of the well depends, first, on the cost of production; second, on the amount of oil produced; therefore it would be impossible under Mr. Johnson's system to set a royalty which would be fair to all concerned. If it is impossible to set it at the beginning, it is certainly further impossible to do it from day to clay. I think it is entirely impracticable of application.

Jan 12, 1915

By J. Elmer Thomas

The evolution of the oil business is one of the great industrial romances of modern times. First used as a medicine, then as a lubricant, then as an illuminant, and finally as a motor fuel, each change in its principal usage caused large increases in consumption. Producing Successes The producing branch of the industry responded ably to the demands made upon it. Never was there a famine, rarely any threat of scarcity, and stored inventories were gradually accumulated to form comfortable working stocks. Originally an erratic and hazardous undertaking, the discovery and development of oil fields has made such strides as to classify now as a science. When storage stocks were low, production in close balance with consumption, and demand trending sharply upward, considerable concern was expressed over future needs. Price was very responsive to fluctuations in supply under those conditions, and quotations for crude and refined oils exhibited wide swings. A very different situation exists today. Consideration of the statistics only since the war will show how recent has been this change. In the 10-year period from 1918 to 1927 inclusive, we produced in the United States 6,100,000,000 bbl. of crude and imported 900,000,000 bbl., our total supply being 7,000,000,000 bbl. The consumption was 6,600,000,000 bbl., thus adding to stocks 400,000,000 bbl., an accumulation of somewhat less than 6 per cent. of the total supply. During that period virtually every field was promptly developed as soon as discovered and nearly every well in the country was producing at full capacity. With the maximum production of the wells required to take care of the rapid increases in consumption, with storage stocks moderate and proven reserves very slight, the producing division of the industry acquired a tempo not needed now. Potential Surplus Today the situation is vastly different. The economic consumption is about 2,700,000 bbl., with current production slightly in excess of that.

Jan 1, 1930

GENERAL COMMITTEE GERALD F. G. SHERMAN, Chairman. ARTHUR NOTMAN, Secretary. NORMAN CARMICHAEL, JOHN C. GREENWAY, W. L. CLARK, W. G. McBRIDE, B. BRITTON GOTTSBERGER, FOREST RUTHERFORD. General Committee on Transportation WALTER DOUGLAS, Chairman. CLEVELAND E. DODGE, Secretary. ARTHUR S. DWIGHT, JOHN C. GREENWAY, JULIUS KRUTTSCHNITT, JR. Committee at El Paso W. D. GORDON, ROBERT McCART, JR., W. W. ROSE. Committee at Santa Rita JOHN M. SULLY, Chairman.

Jan 12, 1916

By W. F. Holbrook, C. E. Wood, E. P. Barrett

The Blast Furnace Studies Section, Metallurgieal Division, Bureau of Mines, has been working for several years on the mechanism of desulphurization of iron and steel by slags. The usual assumption that desulphurization takes place by diffusion of FeS from metal into slag and subsequent reaction of this FeS with CaO to produce CaS has seemed to us inconsistent with a number of experimental results we have obtained. We undertook, for example, to determine the proportion of sulphur in a slag present as FeS. An entirely satisfactory method of doing this has not yet been evolved. The results of extraction with metallic antimony led to an interesting conclusion, however. FeS is readily soluble in metallic antimony, either physically or by chemical reaction. On the other hand, CaS was found to be insoluble. Hence it would appear that by rapid extraction of the slag with antimony we might expect to determine the distribution of sulphur between iron and calcium. The results showed that much of the sulphur was present as FeS. In some instances the extraction of sulphur as FeS was almost quantitative. For example, in a slag containing 3.8 grams Fe and 3.7 grams S, extraction removed 1.18 grams S and 2.12 grams Fe. If all the iron present in the antimony had been FeS, 1.21 grams S would have been extracted. In another slag with 8.6 grams Fe and 0.06 gram S present, 0.14 gram Fe and 0.08 gram S were extracted. This was obviously extraction of sulphur as FeS within the analytical error and showed that FeS was present either in solution or as a dispersion. Attempts to determine the solubility of FeS and CaS in slag by quenching and ultramicroscopic investigation have indicated that the solubility of FeS is very low, and that reactions in the slag are probably not to be considered as homogeneous. A more detailed report on these theoretical considerations will be made at a later date.

Jan 1, 1940

By W. F. Holbrook, C. E. Wood, E. P. Barrett

The Blast Furnace Studies Section, Metallurgieal Division, Bureau of Mines, has been working for several years on the mechanism of desulphurization of iron and steel by slags. The usual assumption that desulphurization takes place by diffusion of FeS from metal into slag and subsequent reaction of this FeS with CaO to produce CaS has seemed to us inconsistent with a number of experimental results we have obtained. We undertook, for example, to determine the proportion of sulphur in a slag present as FeS. An entirely satisfactory method of doing this has not yet been evolved. The results of extraction with metallic antimony led to an interesting conclusion, however. FeS is readily soluble in metallic antimony, either physically or by chemical reaction. On the other hand, CaS was found to be insoluble. Hence it would appear that by rapid extraction of the slag with antimony we might expect to determine the distribution of sulphur between iron and calcium. The results showed that much of the sulphur was present as FeS. In some instances the extraction of sulphur as FeS was almost quantitative. For example, in a slag containing 3.8 grams Fe and 3.7 grams S, extraction removed 1.18 grams S and 2.12 grams Fe. If all the iron present in the antimony had been FeS, 1.21 grams S would have been extracted. In another slag with 8.6 grams Fe and 0.06 gram S present, 0.14 gram Fe and 0.08 gram S were extracted. This was obviously extraction of sulphur as FeS within the analytical error and showed that FeS was present either in solution or as a dispersion. Attempts to determine the solubility of FeS and CaS in slag by quenching and ultramicroscopic investigation have indicated that the solubility of FeS is very low, and that reactions in the slag are probably not to be considered as homogeneous. A more detailed report on these theoretical considerations will be made at a later date.

Jan 1, 1940

By G. K. Manning, E. R. Stein, E. E. Underwood

Columbium, carbon. and nickel additions were made to iron-base alloys with 20 pct CY. The effects on microstructure, precipitation-hardening characteristics, and High-temperature properties were investigated by means of metallographic, hot-hardness, and magnetic measurements. An austenitic alloy consistilzg of Fe-20Cr-14Ni-0.8C-2.5Cb had higher hot-lzaciness at 1700°F than the other alloys investigated. Its favorable standing is attributed to an enhanced interaction of Cb and Cr4C particles dispersed within a stable austenitic matrix. FOR the past 20 years, cobalt- and nickel-base alloys have been used for the more stringent high-temperature applications because of their excellent creep resistance. Although their performance is quite satisfactory, other base materials must be considered for large tonnage, low-cost applications such as for the automotive gas turbine. Iron-base alloys are also used extensively, but at somewhat lower temperatures, primarily because of the instability of particles or because precipitation occurs at relatively low temperatures. Since unusual stability has been reported for Fe-Cb and Cb-C compounds.1-3 it was hoped that effective amounts of these compounds could be taken into solution at temperatures just below the melting range, then precipitated upon reheating. Actually, strengthening was found to occur by both precipitation hardening in some alloys and by phase transformations in others. Among the alloys investigated, that with the best high-temperature properties owes its strengthening to a combination of carbide particle interaction and a relatively stable austenitic matrix. EXPERIMENTAL PROCEDURES Small preliminary melts of about 100 g were made in a vertical Glotube furnace, using alundum crucibles and an argon atmosphere. Alloys weighing 35 lb were melted in a basic-lined induction furnace, also under argon. The compositions of the alloys are given in Table I. The nickel-free alloys were usually ferritic, while those containing nickel were generally austenitic. Depending upon the particular heat treatments, or the combination of alloying elements, two-phase alloys of ferrite and austenite could be obtained. In the following text, however, the nickel-free or nickel-bearing alloys are referred to simply as either ferritic or austenitic alloys respectively. The small ingots were swaged at 2000°F, in steps, to rods of approximately 3/16-in. diam. The large ingots were forged at 2100°F to 1-in. sq bars. No difficulties were encountered in swaging or forging any of the alloys to as much as 90 pct reduction in area. For heat treating at temperatures above 2000°F, specimens were sealed in quartz tubes under a partial pressure of helium. No special precautions were found to be necessary at lower temperatures. Intermetallic compounds in the preliminary alloys were identified by means of X-ray diffraction measurements. Correlation of these results with micro-structural characteristics (such as color, shape, size, and location) of the compounds aided in their identification. Magnetic susceptibilities were also obtained at room temperature with a Magne Gage instrument after the various heat treatments. To

Jan 1, 1962

SINCE you have asked me many times in particular how those mirrors are made that are commonly called spheres,* and even though I have told you at other times, I do not wish to omit writing of it here again in detail, so that you may have as complete information as I can give you, both in order to satisfy you fully and because it belongs among the subdivisions of the subject that I have proposed. Concerning this, I first tell you that it was an ancient discovery, and in those times as today was celebrated, and worthily so. For the effects these mirrors produce are miraculous things incomprehensible to me, and the more I think about it the more I am bedazzled with wonder, nor do I know how to explain by theory of perspective the causes demonstrated by their effects. Marvelous indeed is the beauty of their shining clearness, but much more so is the fact that (according to the shape that the craftsman has chosen to give them) they reflect back the shadow of the things

Jan 1, 1942

By Clifford Frondel

THE aluminum oxide known as corundum has several varieties that have been used as gem materials since ancient times. These include the red variety called ruby, the blue variety sapphire, and the asteriated types of ruby and sapphire. Asteriated sapphire was known to the ancients under the name of astrios, and descriptions of this gem were given by Pliny and other early writers. The relation of these gem materials to each other as varieties of a single species, corundum, was first clearly established by Haüy in 1805 and J. M. Güthe1 in 1809. Natural gem corundum is obtained principally in Ceylon, Siam, Burma, India, and Australia. Star sapphires and rubies always have been highly prized and in recent years have become particularly popular in the United States. Natural star rubies of large size and fine quality are extremely rare and rank with large and fine emeralds and diamonds as the most valuable of gem stones. Interest thus attaches to the recent success in commercially synthesizing star sapphires and rubies of a size and perfection unmatched by nature.

Jan 1, 1954

By W. Francis

OF THE methods that have been used for studying the chemical composition of coal, attack by reagents has not, in general, yielded much information. Most of the reagents used have been strong oxidants such as nitric acid or Schulze's solution. The use of a milder oxidizing agent, such as air at low temperatures, enables progressive changes in the character of the coal substance to be studied and thus helps toward an understanding of its constitution. British bituminous coals frequently have a banded structure. These bands (of four types) can be separated one from another and have been found to possess markedly different chemical characteristics, even when taken from contiguous portions of the same lump coal. It has been found convenient to give each of the ingredients of banded coal a distinctive name, more or less descriptive of its appearance, and the study of the chemistry of bituminous "coal" in England has resolved itself into a study of each ingredient separately. . The coal chosen for this work was taken from the Top Hard seam at East Kirkby colliery, Nottinghamshire, a detailed chemical analysis of which has been recorded by Baranov and Francis.1 The banded structure was well marked and the bands could readily be separated. The research was confined to the brilliant vitreous bands (vitrain), the dull hard bands (durain) and the "sooty partings" (fusain); for previous work had shown that the fourth type, to which the name clarain has been given, is intermediate in character, chemically, between vitrain and durain.

Jan 3, 1925

By F. W. Jessen

The Mechanism of solution of salt and mixed halites of sodium and potassium is reviewed. The variation in the rate of salt removal under both laminar and turbulent flow conditions is discussed. Many changes are possible in the development of solution cavities whether used for production of salts or for storage of hydrocarbons. The parameters influencing the type and shape of cavity formed with single well or multiple well systems are examined and information presented regarding field application of techniques developed and the means of controlling overall configuration of solution cavities.

Jan 1, 1972

By Albert F. J. Bordeaux

The immediate vicinity of the sea-shore, affording special facility for the exportation of ores, makes it possible to work certain mines in the Vladivostok district, which, in more remote places of Siberia., would remain unproductive. Outside of the city of Vladivostok the population is small and the country is very little prospected. Additional discoveries of valuable deposits like the large body of calamine which has recently been opened in the neighborhood of earlier worked lead-silver ores, in the Tetiuhe valley, are still in the field of possibilities. For many years gold alone was produced, in part from the coastal rivers and in part from a quartz-vein on Askold island near Vladivostok. But the production is diminishing, and prospectors are looking for other rivers in the interior, such as the tributaries of the Ussuri. These rivers are now more accessible than formerly, due to the slow but gradual development of colonization by the Russian peasants. The few natives of the country, called Orodjones, are of the Chinese race. They resemble the North American Indian and are hardy fur-hunters. They have given some attention to placers and have already shown good specimens of gold-dust from the rivers Iman, Bikin, Noto, etc. Coal-mining was begun in the Vladivostok region more than 20 years ago, but in a somewhat irregular way. The industry is not as yet important and the best coal-seams are badly prospected, or are even neglected. Copper, lead, and iron exist in several places. The amounts give some encouragement to the anticipation that the discoveries will give rise to important metallurgical works. I here present a review of the various deposits, based upon such safe information as is in hand, when I have not drawn upon my personal observations. Fig. 1 is a map of Eastern Siberia, showing the mineral deposits.

Jan 1, 1913

By C. M. Schwartz, A. E. Austin, W. B. Wilson

High-temperature X-ray diffraction studies were conducted with Th-U alloys with up to 10 wt pet U. The solid solubility of uranium in thorium as a function of temperature was determined by the method of lattice parameters. Thorium will dissolve up to 2.5 wt pet U at 950°, 4.5 wt pet U at 1150°, and 7.5 wt pet U at 1250°C. Determinations were made of the temperature of the transition of thorium and of the effect of uranium upon the transition. The a to ß transition for thorium was observed to occur at 1330' ±20°C. Mean coefficients of expansion were calculated for thorium and two alloys, and for ThO2 in contact with the thorium, using X-ray lattice-parameter data. Values obtained at 950° C for thorium and Tho2 were 12.1 and 9.40 X 10-6 per OC, respectively. Impurities obtained during the X-ray exposure were identified by diffraction and were essentially Tho2 and ThC, with two additional unknown phases being detected. The effect of the impurities upon the results is discussed. DIRECT investigation (i.e., high-temperature X-ray diffraction studies) of the phase diagram of thorium-rich uranium alloys has been shown to be necessary since recent work1 - has disclosed the presence of an allotropic transformation near 1400°C in pure thorium with the room temperature face-centered-cubic phase transforming to a body-cen-tered-cubic structure at the elevated temperature. The effect upon the transition of the addition of uranium to thorium and of the solubility of uranium in thorium at high temperatures remained unknown, yet was of interest in understanding fabrication procedures and elevated temperature use. The present work was undertaken to provide information in this area by determining the transition temperature, the effect of uranium on the transition temperature, and the solubility of uranium in thorium as a function of temperature. Experimental Work The high-temperature diffraction data were obtained using a camera especially designed for the purpose3 and capable of reaching temperatures in excess of 2000°C at pressures as low as 1 x 10." mm Hg. Temperature regulation was provided by regulating the power input to ±0.1 pet variation, and by regulating the water flow through the camera jacket to provide a constant thermal load. The X-ray sample was a rod nominally 80 mil diam, which was further turned down to 20 mil and then etched to 18 mil over 1/2 in. of one end. This was placed in the sample holder and mounted on the camera so that the smaller part was surrounded by a cylindrical tantalum-sheet radiation-type heating element. Diffraction from the sample was recorded on film after passing through a slot in the heating element and radiation-baffle shield and through beryllium vacuum windows. The X-ray film mounting was of the Straumanis type4 with a camera diameter of 114.59 mm. Since previous work of Chiotti' indicated that impurities considerably alter the transition temperature, chemical analysis of the arc melted iodide crystal-bar thorium samples was obtained prior to testing. The analysis disclosed the material to contain as low as 0.001 ±0,0002 wt pet H and 0.007 ±0.001 wt pet 0. Carbon was 0.003 wt pet and nitrogen less than 0.002 wt pet. This material was sealed in mild steel in an inert atmosphere and subsequently hot rolled to 3/8-in. diam rods at a temperature of 732°C. Following removal of the jacket, the material was pickled and cold swaged to 1/8-in. rods, from which the diffraction samples were prepared. The alloys were similarly prepared, with the uranium being added during arc melting. The uranium analyses of the alloys prepared appear in Table I. The experimental procedure for diffraction examination of the three samples of high-purity thorium differed from those of the Th-U alloys. The original practice, later modified, consisted of pumping down the camera with the diffusion pump on and then admitting liquid nitrogen to the cold trap of the system. This was modified for the Th-U alloys by maintaining liquid nitrogen in the cold trap at all times before and while the diffusion pump was heated. This minor change produced a reduction in the amount of carbon pickup by the sample during exposure to the diffusion-pump vapors. The sample was brought to the desired test temperature and exposed for 21/2 hr at pressures which were usually 2 x 10-6 mm Hg, or lower. Exposures were made at

Jan 1, 1959

COAL DIVISION Established as a Division September 20, 1929 A. Lee Barrett, Chairman Ralph E. Kirk, Chairman-elect David R. Mitchell, Secretary-Treasurer Professor of Mining The Pennsylvania State College State College, Pa.

Jan 1, 1952

PUGET SOUND SECTION SIMON H. ASH, Chairman, I. F. LAUCKS, Vice-Chairman, CHARLES SIMENSTAD, Sec.-Treas., 425 Lyon Building, Seattle, Wash. GLENVILLE A. COLLINS, JOHN N. POTT. The Puget Sound Section met at the Arctic Club, Oct. 28, 1916, for the annual meeting. Those present were: Chairman Glenville A. Collins, Vice-Chairman H. L. Manley, Sec.-Treas. Amos Slater, Chester F. Lee, R. P. Tarr, G. E. Rockefeller, Simon Ash, Geo. W. Evans, Joseph Daniels, I. F. Laucks, F. C. Greene, Darsie C. Bard, Marcel Daly, Milnor Roberts, F. A. Hill, Percy E. Wright, and as guest, Mr. Coates of British Columbia. After dinner had been served, Chairman Collins called the meeting to order. The reading of the minutes of the last meeting were suspended upon request of the Secretary. The Secretary read the report from the Committee on the Associated Engineering Societies of Seattle. Upon motion, duly seconded, the report was adopted and placed on file. Mr. Lee, Chairman of the Committee. on the Mining Men's Convention to be held this coming winter, gave his report orally, and upon motion the committee was continued. The report of the Secretary-Treasurer was read, received, and placed on file.

Jan 3, 1917

By William L. Saunders

Many members of the Institute, who participated in the visit made, during the Bethlehem meeting of February, 1906, to the shops of the Ingersoll-Rand Company, at Phillipsburg, N. J., inspected with interest the new Electric-Air drill, which the company had set up for the purpose of showing it in actual operation to American mining engineers. At the request of the Secretary of the Institute, I promised at that time to prepare a paper for our Transactions, describing the construction and advantages of the machine. But such a paper would then necessarily have contained much that was only expected or claimed by the designers and manufacturers of the drill, and not yet incontrovertibly proved by varied and long-continued practice. However moderate such statements might have been, they would have given inevitably to the paper, to some extent at least, the air of a prospectus, rather than of a technical contribution. I therefore decided, with the Secretary's approval, to postpone the writing of the promised paper until it could set forth the results of adequate actual practice, as well as the latest details of construction, etc., based upon practical experience. That period has now arrived. The Electric-Air drill has been exhaustively tested in the field, under varied and arduous conditions and upon the hardest rocks. It is now fairly in the field; its merits and performances are matters of unimpeachable record, and its place among established competitors can be definitely determined. As a representative of the Ingersoll-Rand Co., as well as a member of the Institute, I may be permitted to add that my company, being largely interested in the manufacture of air-coxpressors and machinery driven by compressed air, has no desire to injure its own business by claiming for this new machine that it should immediately supersede all existing applications of pneumatic transmission of power for drilling. On the

Jan 1, 1908