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By D. J. Cox, J. P. Conway, A. E. Gooch

A two-year test conducted by the USBM's Spokane Mining Research Center (SMRC) has proven the feasibility of the yielding rockbolt, a concept which may prove very useful to the mining industry by providing ground support under a variety of conditions. The yielding rockbolt was originally developed in South Africa3 to overcome the limitations of conventional bolting in rock subjected to high-stress or rock burst conditions. The yielding effect is obtained by fitting the bolt prior to thread rolling with a smooth-bore die of internal diameter slightly larger than the shank diameter but smaller than the rolled thread diameter.

Jan 4, 1977

By W. E. Anderson, T. M. Brady

As part of a larger study to identify factors influencing the practical operating life of wire rope used on large draglines in surface coal mining, field trips to operating surface coal mines were made during late 1975. Wire rope performance information was obtained from personnel at 13 mine sites west of the Appalachians. Seventeen pieces of equipment, utilizing bucket sizes ranging from 30 to 220 cu yd (23 to 168 m), were documented. Draglines at large US surface coal mines can be represented as 120 machines having 60-cu yd (46-m3) buckets, moving 1.8 x 10[9] cu yd (1.4 X 10[9] m3) of overburden during 6650 hours of productive availability per year. Based on the limited field study, the calculated downtime resulting from rope-related causes averages 105.6 hours per year for each typical 60-cu yd (43-m3) dragline. The total loss in production from this source alone is thereby estimated at about 25 X 10[6] cu yd (19 X 10[6] m3) annually.

Jan 11, 1979

By Frederick Prime

In this second supplementary list no titles to which an * is pre fixed hare been seen by tlie compiler; and he will be most thankful to have any omiesisne or inaccuracies in the list sent to hiin to be ptiblisi~cd as a third supplement in the next volume of the actiotra. The author is indebted to Prof. J. J. Stevenson, of New Tork, Prof. P. R. Uhlcr and John 'CV. M. Lee, Esq., of Balti more, and Lloyd P. Smith, Esq., of Philadelphia, for valuable assistance. office, allkntorn iron compaxy, 30 South Third Street, Philadelphia, September 5th, 1881. Alabama. Geologiml Survcy of Alabama. report of Progress for 1879 and 1880, by Eugene A. Smith, State Geologist. Montgomery, 1881. 8vo., 158 pp., and 2 maps. California. Omit Report of Hon. T. Butler Ring, iu sopplemeut I. For Trask's Geology and Illdustrial honrecp, etc., in Supplenlvut I., read Tyson's, etc. Fremont's Menloir on Upper Califijrnia, is also published as XXXth Congress, lat Session. Senate Ms. Doc., No 148, and has a map. For Randall's Report in Supplement I, rend Report of the Special Committee in favor of a Geological Snrvey, subrn-itted by Mr. Randall, April 24th, 1861. n.d., 1851. 8cWo., 19 yp. XXXIst Congress, 1st Session, Sen. Ex. Doc., No. 47, Part 2 [Part 1 is Tyson's Report.) RejW of the Secretary of War in further compliance with the Resolution of the Senate?, calling for Colbies of

Jan 1, 1881

By R. M. Fowler, H. L. Hamner

DURING the last 25 years, there appeared in the literature a number of papers describing equipment and operating techniques for the determination of total oxygen in iron and steel. In the early papers, comparatively little attention was paid to side reactions that occur when iron is saturated with carbon at a high temperature in a high vacuum. As more experience was gained with the new method, the limitations appeared. Metals, with a boiling point lower than iron, distilled out of the crucible, condensed in the cooler part of the furnace, and subsequently reacted with carbon monoxide to form oxides and carbon. Aluminum, manganese, and the alkaline earth metals proved troublesome in this respect. Modifications have been devised to overcome the difficulties due to aluminum and manganese, while the alkaline earth metals are not of too much concern as yet to the steel chemist. The reactions of sulphur have received less attention, although it is generally recognized that some carbon disulphide is probably formed. Liquid air traps have been used in some cases to prevent any carbon disulphide from entering the analytical train. Sulphur was not a particular problem at the Union Carbide and Carbon Research Laboratories until the analysis of the irons of higher than usual sulphur contents became necessary. In order to describe the procedure developed for such irons, it will be necessary to first describe the type of vacuum-fusion equipment employed because the operation of vacuum-fusion equipment is an art to a considerable extent. At the Laboratories, vacuum-fusion equipment has been in daily operation since about 1930. Over the years, the evolution of this apparatus has been governed by the versatility required to analyze a wide variety of materials. Since all types of materials from high purity metals to slags are analyzed and, since seldom more than a few samples of one type are analyzed in succession, the apparatus was designed for accuracy and flexibility rather than for speed. A general view of the equipment is shown in Fig. 1, while Fig. 2 shows the relationship of the various parts. In Fig. 2, A is a vertical double-glazed 24X27/8 in. OD silica tube heated with a 20 kva mercury-arc high frequency generator. The tube is closed with a water-cooled brass head attached with de Khotinsky cement. A turret cap fits on this head and is sealed with a 1/8x3 in. "0" ring. The head contains a sight glass and two 8 in. horizontal glass tubes, for sample storage, cemented in with de Khotinsky cement. B is a four-stage Gaede mercury diffusion pump connected to the water-cooled head with a 11/2 in. copper tube through a flange with an "0" ring. The output of the vacuum pump feeds into an automatic Toepler F pump which compresses the gas sample over mercury in the measuring burettes, G and H. There are bypasses in this line for a McLeod gage C and a Piranni gage D, a manometer E, and for initial pumping out of the system with a Cenco Megavac backing-up pump. The reduction crucible shown in Fig. 3 is machined of Tungar Bulb quality (A.G.K.T.E.-2) graphite. The sample is guided into the crucible with the graphite funnel depicted on this figure. The arrangement of the crucible, radiation screens, etc. in the furnace is as follows: A 1 15/16x61/2 in. Alundum thimble, porosity RA-84, with two 1/8 in. holes near the top and opposite each other which take a pair of special tongs used for lowering it in place, is prepared. A 3/4 in. layer of powdered graphite is placed in this Alundum thimble, and the graphite crucible containing 20 g of ingot iron and 0.5 g of carbon is carefully centered on this bed of graphite powder and graphite powder is packed around it to the top of the graphite cru-

Jan 1, 1953

In traversing lately the Sierra Madre, west of Sail Pedro and Guanacevi, I estimated the topographic summit at several points, by aneroid barometer, at about 8,500 ft. Mr. Weed's measurements, 40 miles further north, are from 9,000 to 9,500 ft., and indicate the correctness of the impression I obtained at the time, namely, that the greatest movement in the elevation of the Sierra was between Guanacevi and Guadaloupe y Calvo. This is suggested also by the course of the headwaters of the Rio Conchas and of the Nazas, and by the relative corrasion of the branches of the two streams. Mr. Weed's statements as to the unevenness and great relief of the andesite floor underlying the later dacites and rhyolites are very interesting, and lead me to add that the floor of the andesite breccias and flows is uncovered for several square miles east of Guanacevi. This floor is of reddish, bluish and gray shales, lying horizontal or dipping slightly east. Their age is unknown; but from the interbedded occurrence of copper sulphides, I took it to be Triassic,

Jan 1, 1903

By Paul C. Merritt

Samuel Hopkins, an 18th century inventor from Philadelphia, has been little noted nor long remembered by History, but it was he who on July 31, 1790, obtained what no other man can ever achieve -the first patent issued by the Government of the United States. Signed by President George Washington, the patent guaranteed to Hopkins the protection of the American Government for his "improvement, not known or used before, . . . in the making of Potash . . . by a new Apparatus and Process." The patent itself is no longer important, but it serves as a milestone in the development of an industry that is now rapidly moving to fulfill its role as a mineral to feed the world. Potash ranks as one of the oldest products of Man, having been used as a condiment by the habitants of Gaul a thousand years before Athens achieved its Golden Age of culture. By Hopkins' time, the uses of potash had changed considerably, going primarily into glass-making, tanning, soap, and explosives, yet the same sources and techniques of manufacturing potash used during the earlier 2000 years-that is, leaching of plant ashes in iron pots with water, followed by water evaporation and crystallization of the potassium salts-were still being used.

Jan 10, 1966

By Y. C. Liu, G. A. Alers

The anisotropy of Young's modules has been measured in a series of Cu-Zn alloys containing from 1 to 28 wt pct Zn and cold-rolled to 97.5 pct reduction in thickness. These modulus data show a transition in texture as a function of zinc content. In alloys containing 3 pct Zn or less, the texture is essentially that of copper. A transition is clearly seen to develop in 5 and 8 pct Zn alloys, and to have been completed in a 12 pct Zn alloy. Increasing the proportion of zinc to 28 pct does not produce any further changes in texture. The ease and clarity with which this texture transition can be seen in the modulus data is in great contrast with the inccertainty in the visual detertiination of the range of texture transition from a series of pole figures. It is also shown that the rolling texture of the high zinc content alloys cannot be a one-COIIIponenl texture, characterized by the (110)(112) ideal orientations, as usually assumed. A second, quite important component must also be present. Furthermore, the present data are inconsistent with matrix orientations on which the "oriented growth" hypothesis of the Formation of recrystallization textures is based. THE rolling textures of binary fcc alloy systems have generally been considered to lie between two terminal textures. One of these terminal textures is the copper type and the other is the 70:30 brass type. Alloys of intermediate solute content exhibit a texture which is said to be a transition between the two terminal textures. On the basis of efforts to correlate rolling and recrystallization textures, two concepts have been advanced in the literature on the nature of these transition textures. One school1 suggests that the addition of alloying elements, e.g., zinc, causes a gradual rotation about one of the (111) poles from the (358)( 523) ideal orientation of the copper-type rolling texture to the terminal {1 10)( 112) ideal orientation used to describe the rolling texture of 70:30 brass. This concept is depicted in Fig. 1 with the angle of rotation corresponding approximately to the zinc content and is designated here as the "rotational concept", since the ideal orientation of the transition textures varies continuously with alloy content. The other concept,' the "mixture concept", suggests that the copper-type rolling texture is a two-component texture. {358) (523) and {110)(112). The addition of alloying elements affects only quantitatively the relative amounts of these two components—a decrease in the amount of material in the {385}(523) orientation and an increase of that in the {110)(112) orientation with increasing solute content. An experimental distinction between these two concepts is essential to a better understanding of both the mechanism of formation of rolling textures and the subsequent formation of recrystailization textures in fcc metals. Because of the lack of resolution inherent in pole figures, it has not been possible to differentiate between the two concepts on the basis of this data. Both concepts, in fact, make use of the same set of pole figures but interpret them in a manner acco-rding to the view held.'" Experimental results obtained from inverse pole figures or selected-area electron diffraction3j4 simply -yield more refined pole figures but do not eliminate the ambiguity of interpretation. Quantitative measurement of an entirely different, orientation-dependent property must thus be considered

Jan 1, 1967

By William H. Hallahan

The Friedensville zinc mine of The New Jersey Zinc Company is located about four miles south of Bethlehem, Pennsylvania in the Saucon Valley, an infolded and down faulted block of Cambro-Ordovician carbonate sediments surrounded by hills of pre-Cambrian gneiss and Cambrian quartzite except where breached by Saucon Creek at its entrance into the Lehigh River. The Beekmantown formation of lower Ordovician age is the host for zinc and limonite ores, the former occurring in the lower dolomitic portion thereof and the latter in the upper interbedded dolomite and limestone portion of the section. The Beekmantown is overlain unconformably by the Jacksonburg of middle Ordovician age and according to Miller (2) underlain conformably by about 2500 feet of Cambrian dolomites and 200 feet of the basal Cambrian Hardyston quartzite. Igneous rocks, younger than the Cambro-Ordovician carbonate rocks, are absent in the vicinity of the ore deposits. The major structure is a N60°E-trending saddle-shaped doubly plunging anticline overturned to the north. A syncline lies to the north of the anticline. A thrust fault of substantial displacement repeats the south limb of the anticline. The ore consists of sphalerite and pyrite, along with gangue dolomite and quartz, filling and replacing the sedimentary type matrix of a strata-bound solution collapse breccia in the dolomitic portion of the lower Beekmantown. This breccia was produced in pre-Jacksonburg time as a consequence of uplift, erosion, and development of a karst topography and subsurface drainage system in the Beekmantown. Deposits of both zinc and limonite are present on the vertical north limb, on the crest and on the gently dipping (25°) south limb of the Friedensville anticline; consequently, there is no preferred structural setting for mineralization. Rather this distribution supports the view that the folding is post-ore. Features confirming this view are the development of flow cleavage in the breccia matrix, the deformation of some of the sphalerite, and the fracturing of the pyrite mineralization therein. There is nothing to indicate that the age of mineralization is other than Ordovician and older than Taconic deformation. In the absence of intrusive igneous activity younger than the ore host, the writer suggests that submarine volcanic exhalations associated with the volcanic activity recorded in the eastern eugeosynclinal facies of the Ordovician may be the source of the metal ions.

Jan 1, 1968

By AIME AIME

THOUGH the dust-control systems in the crushing plants and other buildings at Morenci do not differ materially from similar installations in other large copper reduction works, it is probable that in few other plants has as much attention been paid to the dust problem. Possibly the most striking feature of the Morenci installation is the manner in which the necessary equipment has been built into the various structures, and the absence of unsightly pipes, ducts, and fan houses. That this result has been attained is due, in no small part, to the basic conception that the control of the dust in a milling plant should be an essential part of the process itself and not something to be tacked on later after the plant is in operation. The control systems were designed and developed along with the general plant construction program and when the first car of ore was dumped into the crusher the dust-control equipment was ready.

Jan 1, 1942

By William A. Longacre

IN a previous paper1 the author discussed the problem described by the title of this paper, outlining and reviewing the Gish-Rooney method, with comparison and brief analysis of the interpretation techniques of Roman2 and Tagg.3 Some aspects of the simple type of two-layer system were reviewed from various sources.4,5,6 THE TWO-LAYER PROBLEM For the configuration shown in Fig. I, and for any electrode separation A, the apparent resistivity is a function of the relative depth [HA], the overburden resistivity pi, and a factor K defined by the equation [ ] where p2 is the resistivity of the lower bed, Thus, by the known theory of electrical images, [ ] THE MULTILAYER PROBLEM As the number of isotropic, homogeneous, horizontal layers increases, the difficulties of interpretation multiply. The theory becomes much more involved, and in view of the state of our knowledge, the general problem is virtually impossible of exact solution. However, certain types of [ ] multilayer problems can be worked out in terms of two-layer theory. Hummel,7 Pirson,8 Tagg,3 Watson,9 and others have pointed out the possibility of building up approximations of multilayer resistivity curves with suitable combinations of two-layer curves. Many three-layer curves can be constructed in this way to a good degree of accuracy, and special types of four-layer curves can be approximated. It is very likely that as the number of layers increases, the method of combination will not give good approximations except in very special cases, In the analysis of actual field data, the author has found that many obviously multilayer curves can be solved partially with a good degree of accuracy, using the theory that thin adjacent beds may be considered as one layer or zone, and applying two-layer theory to the extremities of the field curve. MODIFIED TAGG METHOD OF INTERPRETATION Tagg's second method, though superior to his first, necessitates a large number

Jan 1, 1941

By Brahm Prakash, R. Schuhmann

Chemical conditions for flotation and nonflotation of cassiterite and fluorite with oleic acid as collector and with alizarin dyes as modifying agents were studied by means of small-scale, vacuum-flotation tests. Artificial cassiterite was prepared for these tests by high-temperature methods, especially by crystallization from borax melts.

Jan 1, 1950

By S. R. B. Cooke, H. S. Choi, I. Iwasaki

In magnetic taconite of the East Mesabi range, quartz, magnetite, and cummingtonite (OH}(Fe, Mg)(Si4O11)2) are the three major ore-forming minerals.' Fine grinding and magnetic separation of the taconite leads to a concentrate analyzing 64 to 65 pct Fe and 8 to 9 pct insoluble; the gangue content of the concentrate arising from the presence of locked magnetite-gangue particles, and of occluded gangue particles in magnetic floccules. To further upgrade such taconite concentrates, flotation appears to offer a particularly promising approach. To evaluate its effectiveness in separation, a knowledge of the flotation characteristics of each mineral comprising the concentrate becomes desirable. The floatability of magnetite and of quartz have already been reported in a previous paper,2 in which the flotation characteristics of the two minerals were correlated with the electrokinetic properties at the mineral-solution interfaces. Since cummingtonite has somewhat intermediate chemical composition between the above-named oxides, the electrokinetic and the flotation behavior of this mineral becomes of interest for both practical and fundamental reasons. In the present article the results of electrophoretic mobility measurements and of Hallimond tube flotation tests on cummingtonite are reported and are compared with those of quartz and magnetite. MATERIALS AND METHODS A sample of cummingtonite-rich taconite, received from the Mitchell pit, near Babbitt, Minn., was crushed and ground through 100 mesh, and the product was fractionated magnetically into three portions. First, a drum-type laboratory cobber was used to separate a highly magnetic portion, consisting mainly of free, but also containing locked, magnetite particles. The cobber tailing was then passed in two stages through a Franz isodynamic separator. The middle fraction was isolated, and, upon examination petrographically, was ascertained to be principally cummingtonite. The 100 to 150 mesh fraction of this sample was selected for the present study. It was cleaned by leaching briefly with hot, dilute HC1 and then by rinsing repeatedly with demineralized water. A ground and elutriated fraction of -5p cummingtonite was used for the electrophoretic measurements.

Jan 1, 1961

By A. H. Geisler, F. Keller

Some of the important changes that take lace in the structure of aluminum alloys are largely submicroscopic in character. This is especially true of the changes that accompany age-hardening and recrys-tallization. Although improved metal-lographic practices have been helpful in indicating some of these changes indirectly, results are limited by the resolving power of optical microscope lenses. The electron microscope, however, provides a new and important means for investigating the fine structure of metals in a range not possible heretofore. It is anticipated that this microscope will yield new and useful information to metallurgists when suitable techniques are developed to utilize its very high resolving power. Several unique methods have been devised to permit the examination of the structure of opaque samples by the electron microscope. These are all based 011 the principle of producing a very thin film that represents the prepared surface of the opaque metal sample, which can be examined in the transmission microscope; however, the available methods fall into three categories, depending on the manner in which the film is obtained. With the oxide-film method developed by Mah13-l7 a very thin surface layer of the metallographic sample is converted into oxide by a thermal, chcmical or anodic treatment. .After removal from the metal sample by one of the special techniques described by Evans,l9 this oxide film is examined in the electron microscope, and is found to portray the structure of the original metal surface. Films formed on aluminum,8,l7 nicke1,7 iron3,8,9 and a nickel-beryllium alloyl1 by heating; films formed on iron8,9 by chemical action; and films formed on aluminum3-'" by anodic oxidation, have been examined. The other two are more recent methods developed principally in this country; they consist in making the thin film in the form of a mold or replica of the surface contour of an etched sample. With the negative replica method the thin film is made directly on the sample; with the positive replica method it is made on a negative reproduction of the sample. With both methods, variations in the contour of the metal sample, caused mainly by etching, produce variations in the thickness of the surface replica. Because of the direct dependence of the amount of scattering of the illuminating electrons upon the thickness of the film penetrated, only the variations in thickness of the replica are responsible for tones in the electron image. Negative replicas are made by forming a thin film of some suitable material directly on the polished and etched metal sample, and derive their name from the fact that after removal from the sample they have the high and low points in the sample reversed, as shown in Fig. I. Nega-

Jan 1, 1944

By F. Keller, A. H. Geisler

Some of the important changes that take lace in the structure of aluminum alloys are largely submicroscopic in character. This is especially true of the changes that accompany age-hardening and recrys-tallization. Although improved metal-lographic practices have been helpful in indicating some of these changes indirectly, results are limited by the resolving power of optical microscope lenses. The electron microscope, however, provides a new and important means for investigating the fine structure of metals in a range not possible heretofore. It is anticipated that this microscope will yield new and useful information to metallurgists when suitable techniques are developed to utilize its very high resolving power. Several unique methods have been devised to permit the examination of the structure of opaque samples by the electron microscope. These are all based 011 the principle of producing a very thin film that represents the prepared surface of the opaque metal sample, which can be examined in the transmission microscope; however, the available methods fall into three categories, depending on the manner in which the film is obtained. With the oxide-film method developed by Mah13-l7 a very thin surface layer of the metallographic sample is converted into oxide by a thermal, chcmical or anodic treatment. .After removal from the metal sample by one of the special techniques described by Evans,l9 this oxide film is examined in the electron microscope, and is found to portray the structure of the original metal surface. Films formed on aluminum,8,l7 nicke1,7 iron3,8,9 and a nickel-beryllium alloyl1 by heating; films formed on iron8,9 by chemical action; and films formed on aluminum3-'" by anodic oxidation, have been examined. The other two are more recent methods developed principally in this country; they consist in making the thin film in the form of a mold or replica of the surface contour of an etched sample. With the negative replica method the thin film is made directly on the sample; with the positive replica method it is made on a negative reproduction of the sample. With both methods, variations in the contour of the metal sample, caused mainly by etching, produce variations in the thickness of the surface replica. Because of the direct dependence of the amount of scattering of the illuminating electrons upon the thickness of the film penetrated, only the variations in thickness of the replica are responsible for tones in the electron image. Negative replicas are made by forming a thin film of some suitable material directly on the polished and etched metal sample, and derive their name from the fact that after removal from the sample they have the high and low points in the sample reversed, as shown in Fig. I. Nega-

Jan 1, 1944

By J. B. DILWORTA

Ix estimating the investment-value of a mining-property or plant, the value of which decreases with operation, it is often necessary to know the sum which must be set aside periodically from earnings either to renew the plant at the end off its life, or to return the capital involved when the earning-power of the investment has ceased. In such cases it is manifestly incorrect simply to divide the total amount to be retired by the number of periods (usually years) during which the investment shall be active, as the sums periodically withdrawn have a certain interest-earning power varying with the length of time they are held and with the opportunities afforded for their investment. But though the interest may be considered to accumulate regularly year by year, yet the rules and tables for compound interest do not apply, owing to the addition of a fixed amount of new money to the total at the beginning of each period. Briefly stated, the problem of sinking-funds is, to find the amount of money which must be periodically set aside at a certain rate of interest, regularly compounded, to yield a certain sum in a given, length of time. In most practical cases the interest is compounded and the fresh amount added at the same time-usually once a year-and on this basis the problem may be solved as follows

Nov 1, 1909

"WELFARE…Welfare endeavor in connection with both the metal and the coal mines of Utah has shown gratifying progress during recent years and both the operators and their employees are deserving of much credit for the efforts put forth to better living, working, educational and receational conditions in most of the mining camps of the state.In the older metal mining camps of Utah, where the towns are incorporated and independent of the mining properties operating in the vicinity, less opportunity is pre¬sented for the companies to exercise efforts looking towards improved welfare conditions than is the case of camps located on company ground and under the full control of operators.Even in such camps, however, as illustrated in Bingham, the companies can do much to better welfare conditions. In this camp the Utah Copper Company has spent $800,000 since 1 920 in the erection of modern brick cottages, apartment houses and the Gemmell Memorial Club. The cottages and apartments have every convenience to be found in up-to-date city homes. The Gemmell Memorial Club, erected and equipped at a cost of $1 75,000, was provided by the company for the benefit of the Utah Copper Company employees living in the canyon and has been made the recreational center for the camp."

Jan 1, 1925

By AIME AIME

N EARLY 1300 members and guests crowded the halls of the Engineering Societies Building during the winter meeting of the Institute just closed, and more than 600 attended the banquet. In variety of program, quality of papers, interest in discussion, and brilliance of social features, the meeting maintained the high reputation of the past. Nothing elaborate in the way of excursions was attempted, experience having proved that February weather in New York is much too uncertain to warrant extensive field trips. A sight-seeing journey up the Hudson to the Bear Mountain bridge was, however, made despite the snows of the week before and the week after. The annual business meeting, while attended by a minority of the members in the building, was marked by the display of keen interest in the work and called out several interesting discussions. The excellent reports of the committees that had organized their work and directed it along definite lines, emphasized the need of funds with which to support assistants or Fellows who shall correlate and put to the highest use the facilities of the Institute in research along technical lines. This thought was developed at the banquet by the retiring president, J. V. W. Reynders, and it is expected that the Directors will take early steps to collect a fund for this purpose. The number of the individual sessions was too great and the papers and discussions too numerous to permit mention here of all the features of inter- est. A general review only follows. The papers and detailed discussions will be printed and sent to members as promptly as possible.

Jan 1, 1926

By Paul M. Tyler

THE winning of metals from Nature has been advanced to a degree of efficiency that commands admiration even in this Machine Age. Economy of human effort underground, in surface plants, and in treatment works, and better means of performing all manner of operations have cut costs and im¬proved products to an extent that seems far beyond the wildest imagin¬ings of those that labored in the days of hand mining and muscular metallurgy. Principles and methods borrowed from other professions and sciences - mechanical engineering, chemistry, and physics-all have con¬tributed to the rapid development of ore production and treatment, but no small part of the achievements must be credited to the free exchange of ideas within the industry itself and mass attack upon problems of mutual concern. The esprit de corps or class consciousness that has contributed so effectively to the progress of the metal industries has been less apparent among nonmetallic mineral producers. As a class they have been handicapped by inadequate contact with the metal-mining fraternity as well as among themselves.

Jan 1, 1935

By H. M. Woodroffe, H. K. Conn, S. J. Rice

World production of asbestos is estimated to be at a current level of almost 3.5 million tons, having more than doubled in the past ten years. A substantial part of the increase has been due to a rapid expansion in the Soviet Union. Production from that country during 1964 is estimated at 1.5 million tons and, as a consequence, Russia has displaced Canada as the leading world producer. Although traditionally the asbestos mining industry has been centered near Sverdlovsk in the Urals, two new producing areas have been under development for some time. It is expected that a new mine will be in operation in 1965 near Kiembi, Kazakhstan, some 300 miles south of Sverdlovsk, and an- other mine at Aktrovak in Tannu-Tuva, west of Lake Baikal. These developments will provide a significant increase in the production capability of Russia. Although internal consumption is expected to increase with the addition of new asbestos- cement producing facilities now under construction in Russia, there is some speculation that exports will also increase.

Jan 2, 1965

By William H. Spice

For the year 1943, exploratory drilling in South Central Texas continued on the sharp decline that started during 1942. Of the 3 counties comprising this district, as now revised to include the same area as is covered by District No. I, Oil and Gas Division, Railroad Commission of Texas, I5 counties are producing oil or gas. Only 29 exploratory wells were drilled during 1943, as compared with 51 exploratory wells in 1942, or a decrease of over 40 per cent. One new oil field and one new gas field were discovered during the year and a new horizon was discovered in an existing oil field. This cornpares with two new oil fields and an extension to an existing gas field in 1942. The one new oil field, South Washburn, in southeastern La Salle County, was discovered by Quintana Petroleum Corporation's No. I-D South Texas indicate in April 1943, flowing 4 bbl. per day, 48" A.P.I. gravity oil with an estimated 4 million cubic feet of gas from Wilcox sand at 6030 ft. This well i's the result of an extensive seismograph survey of the area. It is about 434 miles southwest of the same company's Green Branch field and by the end of the year one dry hole had been drilled to the southwest of this discovery. The one new gas field, which was not named, was located in eastern McMullen County by Edwin M. Jones' No. 102 Ezzell, in November 1943, for an estimated 8 million cubic feet of gas from shallow Jackson sand at 1222 ft. NO addi- tional wells have been drilled in this area, which may also be considered as an extension to the South Calliham field. The one new producing horizon was discovered in the South Campana field in southeastern McMullen County, by Argo Oil Corporation's No. 2-G Edrington, in January 1943, flowing 55 bbl. per day, 21' A.P.I. gravity oil with 40 per cent water from Government wells sand at 2609 feet. None of these discoveries were of major importance and subsequent development in these new areas has proved to be disappointing. Produc'tion for the district during 1943 totaled approximately 6,985,000 bbl. from about 3430 producing wells. This is an increase in production of about 5 per cent over 1942, but a decrease in producing wells of about 10 per cent under the number of wells producing in 1942 for the same district. Average production per well was 5.4 bbl. during 1943 as against 4.8 bbl. during 1942. Approximately 5,320,000 hhl. of this total production, or 76 per cent, was produced by the four Edwards lime fields, Luling, Branyon, Salt Flat, and Darst Creek, which are from 22 to 14 years old. The remaining production came from the 43 other active oil fields in the district. Drilling in the proven fields maintained approximately the same level as for 1942, with a total of 36 wells drilled. Of these operations, 21 were oil wells, one was a gas well and 14 were dry holes. This is a slightly better proportion of producers than for 1942. Washburn field had the greatest number of new producing wells drilled during the year, with a total of 10.

Jan 1, 1944