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By Lennart Bergstedt, Olov Fägremo

Boliden Metall Aktiebolag, the prime base metal mining company of Sweden, treats some 10-10.9 t/y (11-12 stpy) of sulphide ore in nine concentrators. During the years considerable effort has been devoted to the development of all phases of the technology of ore prospecting, mining, milling, smelting and refining. This has been necessary due to the complex and low grade ores. The autogenous grinding technique was first studied within the company as early as 1945. Basic test work commenced during the early fifties, whereby the merits of pebble grinding could be evaluated. In parallel with the converting of the rod mill/ball mill grinding systems to rod mill/pebble mill systems, the development work concerning the feasibility of autogenous grinding went on resulting in the installation of a 8 6.7 x 2.1 m (8 22 x 7 ft.) cascade mill at the Vassbo lead mine in 1959. Long term tests at the Vassbo plant together with a number of pilot plant test involving low grade silicious ores and pyritic comples base metal ores successive led to a better understanding of the process of autogenous grinding. Before a two stage autogenous grinding system could be chosen for the expansion of the Aitik copper mine, a carefully planned survey concerning grinding characteristics and variances in the ore and flowsheet was undertaken. The expanded plant went on stream in 1972 and in the beginning of 1973 and since then has performed excellently.

Jan 1, 1979

By H. R. Tunnell

EVERY ONE connected with a mine knows that it is hard to keep down the costs of moving ore from the place where it is broken to the shaft or portal. Considered broadly, the subject of handling would cover all work done in a mine, but here it has been limited to handling ore in stopes and drifts, through chutes, and on levels. Good Ventilation and a strict enforcement of rules for the prevention of dust safeguard the health of the men and lower transportation costs. HANDLING ORE IN STOPES AND DRIFTS The object of all stoping is to mine ore of good grade at low cost. In Butte, the major part of the ore is mined, from Veins dipping from 60° to the horizontal to those which are vertical, by means of, square-set, rill, -timbered-rill, and back-filling stopes. When blasted, a part of the rock is carried by gravity to the grizzlies over the chutes, the rest is shoveled. Rock, when broken in a stope, may be deflected by inclined floors or slides toward the top of a chute leading to the level below. Ore broken clean enough to ship should be carried, by the force of its fall, into a chute or as nearly into that chute as the safety of the stope and the men permits. Ore that requires sorting, about 80 per cent. of all ore mined, is caught on a grizzly and the waste picked out. Waste rock broken in a stope is used to fill that stope and should be blasted into the gob with as little handling as possible.

Jan 2, 1922

By J. G. Montgomery

An increased drilling activity was apparent in the shallow sand fields of northwestern Pennsylvania during the year. This drilling, however, was confined to previously outlined productive areas and as new shallow sand pools of interest were discovered. Drilling for Oriskany gas proceeded at about the same rate as in previous years. One new area in Kinzua township, Warren County, was opened up during the year by a producing well, but later this well developed salt water and the productive capacities of the area are very indefinite at the present time. Production from the shallow sand areas remained approximately the same as in 1935. Production from the Oriskany or deep sand areas increased approximately 20 per cent. Two new markets were made available for the Oriskany gas during the closing months of the year by the completion of the Peoples Natural Gas Co. line from the Hebron field to Clarion County, Pa. and Penn York Gas Co. line from the Harrison field to points in northwestern New York State. With the exception of the Kinzua well, the few deep wildcat wells drilled during the year failed to discover new fields in the deep sands. Bradford Oil Field The accompanying data on the Bradford oil field include only the production obtained from the portion of that field that is in the State of Pennsylvania, for it appears probable that Cattaraugus County production, which consists mainly of the New York State portion of the Bradford field, will be included in annual oil production figures for New York State. The Bradford field production for 1936 totaled 14,533,000 bbl., and as it is necessary to estimate New York State production for the Bradford field, the accompanying data includes the production from the Pennsylvania end of the Bradford field of 13,208,000 bbl., which is an increase of approximately 8 per cent over 1935 production.

Jan 1, 1937

Meeting, Aug. 20, 1913, B te, Montana, at 12.45 p.m.-On, the written request of 27 members of oft Institute residing in Montana, the Montana Local Section was established, and the following Committee was appointed by the President of the Institute to complete the organization : E. P. Mathewson, Chair pan; Frank M. Smith, Vice-Chairman; D. C. Bard, Secre-tary, Montana State School of Mines, Butte, Mont., Oscar Rohn, James L. Bruce. The President reported the appointment of a Committee on Mining Law, the names of whose officers and members are given on page xxxv of this Bulletin, and these appointments were approved. It was voted: That the Committee on dining Law be requested to establish a Sub-Committee on Censorship, a majority of whom shall be lawyers; and, further, that no paper on mining law be recommended for publication to the Committee on Papers and Publications, unless it is previously approved by the Sub-Committee on Censorship of the Committee on Mining Law. The President reported progress in the matter of co-operation between the Institute and the United States Bureau of Mines, through Committees of the Institute. The President reviewed the history of plans for a union or affiliation with the Mining and Metallurgical Society of America, and the following minute was then adopted : " The Board of Directors of the American Institute of Mining Engineers has carefully considered for several months the question of union or affiliation with the Mining and Metallurgical Society of America ; and, while at an earlier time and under other circumstances, such. a union might have been accomplished, yet under present circumstances the Directors of the Institute deem such union inexpedient. "While thanking the Mining and Metallurgical Society of America for its consideration of the matter, we believe that further discussion of the subject will serve no useful end, and we conclude it best that the Society and the Institute continue their useful functions and friendly relations side by side, as heretofore."

Jan 10, 1913

The work of the Committee during the year 1914 was especially directed to the securing of a larger representation in the Institute of those engaged in coal mining and coking. While these industries exceed in volume and in monetary importance all other mining industries in the United States, the membership of the Institute representing them has in recent years been relatively small. It was thought that an increase in the membership of the Institute obtained from among those engaged in these industries was desirable in order to increase interest in the work of the Institute, for this result can only be reached by securing the presentation and publication of a larger number of papers relating to these industries. It is evident that the reading of such papers will tend to increase the attendance at the local and general meetings of the Institute. Sessions of the Coal and Coke Committee were held and a number of papers relating to these subjects were presented at the meetings at Butte, Salt Lake, and Pittsburgh, the Pittsburgh meeting especially being planned with this in view. The activities of the Local Section of the Institute organized in the Pennsylvania Anthracite region have reawakened interest in that district and it is hoped that the same object can be obtained in the bituminous coal fields, either through the organization of one or more. local sections, affiliation with some of the local coal-mining societies, or through activities of the Coal and Coke Committee. Referring to the work of the Committee in its efforts to increase the membership of the Institute, the Committee desires to acknowledge the services rendered by many members scattered throughout the various coal-mining districts of the United States, in compiling lists of those qualified for membership in the Institute, but who have not yet become members. The lists so compiled comprised about 1,100 names, which were furnished to the Committee by the co-operation of 40 or 50 members of the Institute.

Jan 3, 1915

By M. A. Mallinger

A series of laboratory tests was conducted to determine the limits of practicability in regulating the weights of various cement slurries. It was found that slurry weights of 12 to 19 lb per gallon could be obtained by adding bentonite to decrease the weight and barytes ore to increase the weight. It was also found that barytes ore was not usable in all cements. LIGHTWEIGHT CEMENT SLURRIES INTRODUCTION During the drilling and completion of oil wells the magnitude of the hydraulic pressures exerted on certain formations is critical. In many cases considerable care must be exercised to prevent drilling mud weights from becoming too high, and in those wells where loss of circulation is a problem, the use of normal weight cement slurries will generally result in lost returns during casing cementing operations. While mud weights can easily be controlled, it is necessary to exercise care in the selection of weight reducing additives for cement slurries in order that slurry weights may be reduced sufficiently to prevent the loss of a large portion of the cement to the thief formations without seriously affecting the setting properties of the cement. EXPERIMENTAL RESULTS An extensive search revealed that a large number of materials .that might have been otherwise practicable as a weight reducing additive were not acceptable for use with oil we cements because the imposition of pressure on the slurries caused the additive being tested to be compressed or to absorb water from the slurries, resulting in negligible decrease in the slurry weight. This search for lightweight additives disclosed that bentonite, a material very commonly used for reducing the weight of drilling muds and cements, produced the best results without undue harmful effects on the properties of oil well cements. It was found that there was a limit to the amount of benton-

Jan 1, 1950

By Samuel Lasky

THE writer has been interested in determining the mineralogic dis-tribution of silver in the base-metal ore of the Ground Hog mine of the Asarco Mining Co. in the Central mining district of New Mexico.1 This ore consists of a varitextured mixture of sphalerite, chalcopyrite, galena and pyrite in a quartz gangue. The average ore contains 14 per, cent of zinc, 9.5 per cent of lead, 5 per cent of copper, and 10 oz. of silver per ton. Generally it is accepted that the silver in ores of this type, in which no definite silver minerals can be recognized, is contained in the base-metal minerals. Published assays of pure mineral specimens from many dis-tricts show that each of the base-metal minerals contributes in some degree to the total silver content of the ores, and to determine the pro-portionate amount contributed by each mineral in any specific ore it has been the practice to assay selected specimens of each mineral, the purity of which has been determined microscopically. There being no such assays available for the Ground Hog ore, and it being impract cable to have enough of them made to give average results, the writer resorted to a mathematical attack upon composite assays of large quantities of ore and concentrates. Surprising results were obtained, and it is the threefold purpose of this paper to present these results, to describe the mathe-matical method used, and to point out the value of using this method even when assays of pure specimens are available.

Jan 1, 1934

By John Fulton

The following table shows the shipments from the four Lake Superior iron-ore districts during the year 1887, and their total outputs from their beginning until the close of 1887.* It will be noted that the Menominee district is second in importance in its total output tonnage to the close of the year 1887. These ore deposits are found in jasper-slates and in the horizon between these and their associated clay-slates; in the latter they are true contact-deposits. They are found in this jasper- and clay-slate formation under varied conditions, yet, in all, certain characteristic laws are preserved. The angle of dip varies from 15° to 20°, and up to 85° and even 90°, with the horizon. The ore is rather soft, bluish-black in color, and is a hematite. It varies in thickness from a few inches to one hundred feet, or more. It is mainly "Bessemer" ore, containing 57 to 63 per cent, of metallic iron, and .03 to .07 per cent, of phosphorus. In the mining nomenclature of this range two conditions of the ore-lens are described by the terms "dip" and "pitch." The former is in common use in defining the relation of the ore-plane to the horizon ; the latter indicates the posture of the ore-body as it inclines east or west from its position at the opening of the mine. In the

Jan 1, 1888

By C. C. RAE

The Texas Panhandle produced 18,677,000 bbl. of oil in 1932 as against 25,064,000 in 1931. The decline was caused by smaller market demand, since the Railroad Commission potential increased from 105,528 to 149,260 bbl. during the year. Well Completions, 1932 The development during 1932 compares with 1931' as follows: Year Wells Drilled Dry Holes Gas Wells Oil Wells Initial Pro- duction, Bbl. 1931 200 6 77 117 347 1932 136 18 28 90 603 Crude oil prices, small market demand, and lower allowable rate of production caused less drilling. Expiration of leases was one reason for a greater number of dry holes through forced drilling of questionable areas. The small number of gas wells reflected the influence of the business depression upon industrial and domestic gas demand, together with difficulties of franchise negotiations or pipe line extensions under present conditions. Probably much of the gas-well drilling was done on expiration leases, or to protect against drainage, and equalize withdrawals as between the various units held by each gas pipe line company. The increase in average initial daily production was due chiefly to excellent granite wash wells in the LeFors district developed by the Texas Co. and Skelly Oil Company. In the Panhandle district, comprising a major anticline with almost a million productive gas acres, the pools tend to merge in time, the development being confined to more productive areas. Hence separation into pools becomes a matter of time of development with some effort to keep dolomite, archosic and granite wash production separate. Many pools, like the Finley and Bowers, have mainly one type, but many leases and even individual wells produce from two zones. The oil production is usually closely associated with sea level, where proper porous formations

Jan 1, 1933

By Kenneth Cottingham

The number of completions in 1944 in Ohio was only slightly greater than completions in the preceding year, but the initial daily volumes both of oil wells and gas wells declined considerably. The dry-hole ratio was a little lower than in 1943, even though in the year under review considerable effort was made to find new production. No new areas of consequence were discovered. Thirteen new gas pools, the largest of which was 1000 acres and the average 565 acres, were opened during the year. Eleven of these pools were in the Clinton sand, one was in the Oriskany, and one was in the Berea. Approximately 15 small pools might also be rated as discoveries, but because only one or two wells have thus far been completed in each, they cannot at present be properly evaluated. The latter pools average about 120 acres each. Some extensions were made to existing gas pools. The number of oil wells drilled was only one less than in 1943, yet compared with the year 1941, when twice as many oil wells were drilled, the difference is startling. Effective Aug. I, 1944, a blanket subsidy was granted of 35¢ per barrel on all Cleveland-Chatham, Coming, and Lima grades of oil, and 75¢ per barrel on Pennsylvania grade crude. The subsidy was authorized by the Office of Price Administration, with reimbursement to purchasers of the various grades made through the Defense Supplies Corporation, a branch of Reconstruction Finance Corporation. For several years the small operator, particularly the owner of stripper wells, was in a serious position. The subsidy has been a means of real help and, in addition to aiding the operator, it has prolonged the life of many small wells that otherwise would have been abandoned, with consequent loss of daily production and unre-covered reserves. It is questionable whether the price increase is sufficient to revive production of Corning grade, which has

Jan 1, 1945

By F. T. Lee

Directional dependence of strength and deformation properties of the Mount Waldo granite pluton in southeastern Maine is controlled by joints and microfractures whose orientations are linked to flow- induced alignment of microcline crystals. Longitudinal and cross joints which formed during cooling of the mass, as well as much younger sheeting fractures, are commonly associated with subparallel, discontinuous microfractures. The orthogonality of microfractures (open, closed; filled, unfilled; bubble planes) establishes the ease of splitting of the granite. The easiest splitting direction (rift) is subhorizontal, the second easiest direction (grain) is parallel to the cross joints, while the direction of least easy splitting (hardway) is parallel to the longitudinal joints. Static and dynamic measurements made in the field and laboratory established that structural features are responsible for the marked stiffness anisotropy of the granite. In the central part of the pluton the static Young's modulus in the north-south direction averages 31.1 GPa, and 20.9 GPa in the east-west direction; the stiffer direction being parallel to the long C-axes of microcline phenocrysts and microfractures as identified in outcrop, core samples, and thin sections. Vertical downhole sonic measurements of dynamic moduli ranging from 2.5 to 16.2 GPa appeared to be anomalously low when compared to the static horizontal values. However, the field sonic values were confirmed by laboratory sonic pulse testing of oriented cores. The field results reflected closely spaced layers of open horizontal microfractures. Those deformation and strength properties that are closely tied to bubble planes, filled microfractures, and microcline orientation could be extrapolated to greater depths with good hope of success.

Jan 1, 1984

By Benj. E. Shackelford

THE present paper is concerned with typical temperature values experienced in lamp-filament measurements as made on regular factory and engineering products. It deals with the relations existing between temperature, efficiency, lamp size, and life of incandescent lamps, insofar as they affect the rating of the product and its use by the individual consumer. The temperatures measured lie in that range covered only by the general method of radiation pyrometry, as opposed to direct methods used under contact conditions. The range of temperatures ordinarily experienced extends from about 2125° K., for the now almost extinct carbon-filament lamp, to 3200° K. for the comparatively new tungsten-filament motion-picture lamp. Most of the more common sizes of tungsten lamps have temperatures ranging from 2500 to 3000° K. Because of the high temperatures involved and the relatively small area of the sources used, we are practically restricted to two methods of measurement, both of which depend on the light radiated front the filament. The first and more usual method is that of the Morse pyrometer, dependent on the variation in temperature of the amount of light of a given color range yielded by the filament. In this case, the measured temperature is that of a small part of the incandescent body, that is, the part which is focused on the comparison filament. The second method, known usually in this country as that of "color match" and in England as "color-identity" is based on the color of the total light yielded by the filament, the comparison being facilitated by the use of an ordinary photometer- head. A more definite idea of the temperatures involved in the case of filaments of various vacuum and gas-filled lamps, is given by Fig. 1. The size of the lamp, in watts, is plotted along the horizontal axis and the temperature of the filament is plotted along the vertical axis. The lamps concerned are regular product, rated for 1000 hr. life. The temperature values for the old 16-candlepower carbon lamp and the new motion-picture lamp are shown by the cross and circle respectively.

Jan 9, 1919

By W. C. Schroeder

PRACTICAL experience has shown that at elevated temperatures solu-tions containing sodium hydroxide may attack stressed steel in a manner that cannot be explained in terms of ordinary corrosion. Because the ductility of the metal has been greatly reduced during the reaction, the entire phenomenon is usually called "embrittlement." Thus, after several years of operation caustic evaporators have been so badly embrittled that rivets could be cracked off with the blow of a hammer. Since fine intergranular cracks are almost always present in the zone of fracture, it has often been assumed that a process of selective corrosion in grain boundaries was responsible for the failure, although this has not been clearly proved experimentally. Concentrations of sodium hydroxide below those necessary for the uniform, rapid attack of the steel surface are reported to be most effective in producing embrittlement2,3. In the operation of steam boilers a similar type of failure has been found, mainly in riveted seams or other capillary spaces where the solu-tion may concentrate and where high stresses may also exist. It is believed that in such localized areas the dissolved solids may reach a value many times the few hundred parts per million prevalent in the body of the boiler. While this type of boiler failure has been the subject of investigation for a period of 20 years', an understanding of its mecha-

Jan 1, 1936

By Edgar G. Hill

MUCH has been written and said recently about the methods used and materials and equipment employed in building the long tubes that criss-cross a great part of the [ ] united States, like the pattern of a spider's web. This paper will discuss the fundamentals of design of these lines from the economic as well as the engineering view-point, pointing out the effect of the volumes transported, and the load factor at which they are operated, on the unit costs of transportation, as well as the effects on costs of the character of the fluids the lines are called upon to handle. Generally speaking, crude-oil pipe lines carry oil from the producing fields to the [ ] refineries. Sometimes part of the journey is by pipe line to a coastal point and tank ships are employed for the rest of the trip. The main lines of directional flow of crude oil through pipe lines in the United States are shown on Fig. I, but this, of course, does not always show individual pipe lines. BASIC FORMULA FOR FLOW OF CRUDE OIL The laws governing the flow of crude oil through pipes are well known. The basic

Jan 1, 1942

By N. J. Gran, W. R. Opie

HYDROGEN in molten aluminum and aluminum alloys, which precipitates during cooling and solidification, is the principal cause of pin hole porosity in ingots and castings. Much attention has been given to determining the effect of temperature and pressure on the solubility of hydrogen in pure aluminum, but little data are available on hydrogen solubility in aluminum alloys. This investigation was undertaken to check results reported for pure aluminum and to show the effect of silicon and copper additions on the amount of hydrogen contained by molten alloys. Previous determinations of the solubility of hy-drogen in molten pure aluminum are plotted in fig. 1. The most reliable data appear to be those of Ransley and Neufeldl and of Baukloh and Oester-len.' The latter authors also report some results on the effect of copper and silicon additions. Up to 6 pct these elements decrease the solubility of hydrogen quite rapidly, with a definite minimum noted at 6 wt pct for both copper and for silicon, although no reason is apparent for these minima. Experimental Procedure The solubility of dry hydrogen in pure aluminum, aluminum-silicon, and aluminum-copper alloys was determined by the method of Sieverts.8 This consists of determining the volume of the gas system above the molten metal at a given temperature and pressure by using an insoluble gas. This volume is referred to as the "hot volume." The system is then evacuated and the soluble gas is introduced at the same temperature and until the same pressure is reached. It is necessary to introduce enough of the soluble gas to fill the space above the metal plus the soluble amount. The difference in the volume of soluble gas and the "hot volume" is the solubility. The accuracy of solubility measurements by the Sieverts' method is primarily depend-

Jan 1, 1951

By Frederic H. Wright

The secondary metals industry might well be defined as the group of remelters, smelters, refiners, and manufacturers that convert scrap metals or residues to commercial forms. In this industry, scrap metals and residues are processed to pro- duce refined metals, ingot alloys, fabricated shapes, and chemical products. Secondary metal is defined as metal recovered from commercial scrap, that is, scrap that has entered the processor's plant in scrap form. Metal recovered by a manufacturer from "home scrap" generated in his own plant is not considered to be secondary, because it represents part of the original stock that simply requires additional treatment before emerging as a finished product. In any economic study, a basic point of measurement must be chosen, and in the case of secondary metals, the melting pot or its counterpart represents the stage in which metal is converted from scrap to some more usable form. Beyond this point there is often no means to distinguish between secondary metal recovered from scrap and virgin metal produced directly from ore. In the last fifteen or twenty years the secondary metals industry has grown to major importance. Some consumers distrust secondary metals, but frequently this distrust serves only to prove an inability to keep up with the times. A rapidly decreasing number of manufacturers like to boast that they use only virgin metals, but a little investigation would show them that more than one third of all

Jan 1, 1943

By G. W. Traer

THE distillation of bituminous coals at what is commonly termed low temperature, and the quantities, nature and adaptabilities of the products have been the subject of considerable experimentation, during recent years. Fortunately, the earlier work in this country was done by men whose scientific training qualified them properly to record and interpret the results of-their experiments. The work of Prof. Parr, of the University of Illinois, is especially notable in this respect. Prof. Parr's work, added to that of English experimenters, demonstrated certain things to a degree which is generally regarded as convincing. They have proved that a caking bituminous coal, when subjected to a temperature of not more than 1000° F. (preferably somewhat less) will yield light tar having low specific gravity (about 1.06) and high value; also, that this yield, with a given coal, will depend upon the percentage of hydrocarbons in the coal, the maximum temperature used, and the promptness with which the distillate gases are removed. It is assumed that air is excluded from the retort, and that the coal is subjected to heat for a sufficient time to drive off all of the tarry hydrocarbons. The results attained in the first, or low-temperature stage of the Carbocoal process, recently described by C. T. Malcolmson, corroborate these general principles. It is the purpose of the writer to describe other work of a practical nature, directed toward the commercial adaptation of these principles, which was begun nearly two years ago; this investigation was assisted by A. J. Sayers, of the Link-Belt Co., and Carl Scholz.

Jan 9, 1918

By Arnold J. Rothstein, Raymond Kaufman

A large number of firms and institutions have evaluated possibilities of mining the manganese nodule source, beginning with a major effort in 1957-58. There have been as many as ten commercial firms actively engaged in major programs of engineering and development, including Deepsea Ventures/Tenneco, Hughes Tool Co., Kennecott Copper Corp. and Ocean Resources, Inc. Foreign firms active in the field are International Nickel CO., Sumitomo Group/MITI, AMR (a joint venture of three West German companies-Metallgesell- schaft AG, Preussag and Salzgitter AG), and Societe le Nickel (CNEXO). It is estimated that it will take from 11 to 19 years for the more successful ventures to reach operational levels. Investment Costs and Rates of Return Five different programs, all from public sources, have been studied to analyze dollar figures regarding investment costs and the possible return on these costs. All are based on a unit of production of a million tpy of dry nodules through the processing plant, which is considered the minimum likely capacity. The costs are not always comparable, and with some liberties, have been forced into two categories. The first covers mining and sea-related costs. The second will include the onshore processing and other costs such as administrative and distribution figures. The costs in all cases are for complete ventures extending from prospecting through mining, processing and distribution of several metals and other products derived from the nodules. All costs are joint product costs, making certain comparisons with land mining difficult.

Jan 4, 1974

Body Hoists A complete new line of hydraulic dump truck body hoists and bodies featuring many outstanding design improvements has just been announced by St Paul Hydraulic Hoist Fourteen models of this new hoist are available in a selection of capacities from 6 to 25 tons The new body hoist features low standard mounting height, advanced lifting point, new low operating oil pres [ ] sures, a new Uniflex subframe, friction-free roller bearing drive mechanism, including pump and power takeoff, to insure quiet operation and long trouble-free life A stress-eliminating design feature of the new hoists absorbs dumping shocks and permits use of a new principle in hoist design a flexible subframe which ends tendency of rigid hoists to crack or bend when flexed Circle No. 1 Combination Drill A new combination drill offering all three methods rotary, auger, and percussion drilling on the same rig is the revolutionary feature of the latest drill rig designed by Mobile Drilling Inc The B-36 drill is larger, more powerful and versatile than previous models built by this company This new drill has a hydraulic feed of approximately 8000 lb pressure The hydraulic feed cylinder is located directly over the rotary turn table The carriage of the drill is of tubular construction The drill mast, also of tubular construction, nests in the tube members of the drill carriage for cross-country travel with a maximum overall height of 10 ft The drill mast telescopes together with the feed cylinder hydraulically to an operating height of 16 ft The drill can be furnished with an auxiliary cat head, sand reel, and special high pressure water pump The B-36 maximum depth for auger drilling without water is approximately 150 ft, depth for rotary drilling with water is in excess of 300 ft Circle No 2

Jan 1, 1952

By M. N. Short

It is almost self-evident that the student of geology depends for his education in geology only in small measure upon his own observation. His chief sources of information are lectures and personal instruction from teachers, and the geological literature. Of these, the literature is by far the most important. The total geological knowledge available to the geologist of today is substantially that which is on the printed page, and no more than that. There are many geologists of outstanding rank who during the course of a busy and useful professional career have accumulated valuable geological knowledge. This, however, is never available to the profession, owing to the disinclination of these geologists to write or to the refusal of their employers to allow the results of their work to be published. With the passing of these geologists, their accumulated knowledge is irretrievably lost. In many mining districts the operating companies are not averse to the publication of geological information gathered by their engineering and geological staffs, but for various reasons this information is not published. However, when a public survey geologist goes into the district this information is placed at his disposal and eventually is published. But for the intervention of a disinterested public scientist, this information would have been buried in company files. In the last analysis, the teachers themselves depend largely upon the printed page for the knowledge they pass on to the student. Without geological literature, then, the instruction of geological students would be almost impossible. There is no .question that, as a whole, geologists who are on the public payroll have to their credit far more contributions to literature than have either teachers or professional geologists, whether the latter be independent or in the employ of private corporations. The very fact that geologists are upon the public payroll places them under obligation to make available to the public the results of their endeavors. They must either prepare these results for publication or they must furnish data or otherwise aid their colleagues to publish their results. The success or failure of a public geological survey depends entirely on the

Jan 1, 1935