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NEW MEMBERS The following list comprises the names of those persons who became members during the period Feb. 10, 1916 to Mar. 10, 1916. ALLAN, FERGUS L., Min. Engr., Cons. Min. Engr., Mexico Mines of El Oro, El Oro, Mex. ARMSTRONG, EMERSON WARREN, Met.,. Mina Bibilonia, La Libertad, Nicaragua, C. A. BABB, P. A Blaisdell Coscotitlan Syndicate, Pachuca, Hgo., Mex. BANDY, PERCY J Fundicion Delicias, Calle Delicias, Mexico, D. F. BELLWALD, J. N Apartado 1488, Mexico, D. F. BILLICK, DON CARLOS, Min. Engr., Supt., Hess Gold Mines Co., Alturas, Modoc Co., Cal. BITLER, FRANK L., Cons. Min. Engr., Birkinbine Engineering Offices, Parkway Bldg., Broad and Cherry Sts.. Philadelphia. Pa.

Jan 4, 1916

By S. S. Clarke

THE opening of zinc-lead ore bodies in the lower chert beds of the Tri-State district, locally called sheet-ground deposits, [ ] presented several new economic operating problems to be solved before the low-grade deposits could be mined profitably. Drilling was the first high-cost problem and loading and haulage difficulties followed. At this time, the sheet-ground mines are producing about 2000 tons per day. GEOLOGY The geology and ore deposits of the Tri-State district have been covered in detail by [ ] Fowler and Lyden.* Briefly, the sheet-

Jan 1, 1942

By C. G. Rhodes, D. Kramer

High-field critical transport current density (J) measurements at 4.2 °K as a Junction of applied magnetic field (H) were made on samples of cold-rolled and annealed columbium with H parallel to J. Microscopic examination of the samples revealed a well-defined planar fiber structure produced by the cold rolling. J was found to he lower when fibers are parallel to the direction of magnetic field penetration than when they are perpendicular. This effect may he a consequence of the interaction of flux movement with fiber boundaries. THE severe changes in microstructure brought about by cold working superconductors leads to profound changes in their superconducting behavior. In particular, the ability of a superconductor to carry a transport current with zero resistance (the maximum value of this current density will be called "J" in the presence of large external magnetic fields (to be referred to as "H") is greatly influenced by the microstructure. In the case of columbium, LeBlanc and Little1 and Autler et a1.2 have observed an increase in J due to cold work. LeBlanc and Little also observed an anisotropy in J in cold-rolled columbium strips, which Hake et al.3-6 have shown to depend upon the angle between H (H ? J) and the rolling plane. An increase in J due to cold work has been found in a variety of high-field superconducting alloys3'4'7-9 as has the anisotropy effect.10 First explanations of why cold work raised J invoked the idea that dislocations carried the high-field supercurrents,8,11 since cold working drastically increases the dislocation density and presumably the number of supercurrent paths. However, recent ideas on the nature of high-field superconductivity together with new experimental evidence reveal that the bulk of certain superconductors can remain superconducting in high fields while carrying high transport currents. These later developments have been discussed by Berlin-court and Hake12 and a comprehensive review has been prepared by Berlincourt.13 According to the ideas of Gorter14 and Anderson,15 one would expect that the influence of microstructure on high-field supercurrent density will depend on tine interaction between microstructure and penetrating flux and on the direction of the Lorentz

Jan 1, 1965

NEW MEMBERS The following list comprises the names of those persons who became members during the period Apr. 10 to May 10, 1915: Members ADMAN, WILLIAM, Supt., Susquehanna Coal Co Lykens, Pa. BARTH, CARL G., JR., Min. Engr 6151 Columbia Ave., Philadelphia, Pa. BOOTH, ERIC EDWIN, Min. Engr., Mount Elliott Mine, Selwyn via Cloncurry, North Queensland, Australia. BOYDELL, HARRY CYRIL, Asst. Mgr., Randfontein Central Gold Min. Co., Box 42, Randfontein, Transvaal, South Africa. BRADY, SAMUEL HOWARD, Mine Supt Bohemian Club, .San Francisco, Cal. Buses, HARRY EDWARD, Mine Supt., Engels Copper MiningCo Keddie, Cal.

Jan 6, 1915

By A. Weiss, W. A. Coster

The search for ore is characterized by a great variety of uncertainties, each of which can be resolved by obtaining information at a cost. Three exploration stages may be distinguished in which information can be obtained, based on inherently different cost structure: 1) the reconnaissance or scanning stage, 2) the examination or screening stage and 3) the project stage. This exploration sequence would roughly coincide with replies to questions as to: where, how, why and how much. As complete information in each stage is too costly to acquire, we must assess the probability that adequate information will be furnished by a limited amount of effort and attempt to maximize the expected value of ore to be found for a given exploration expenditure. Several problems are discussed relative to the mathematical formulation and possible computer procedures for determining the optimum allocation of a total exploration effort. Based on the available literature possible solutions to this problem are indicated. When scanning through published literature on mineral exploration, it seems at first that there is little room for substantial and systematic improvements in the efficiency with which the problem of discovery of new ore deposits is presently being handled by large organizations active in exploration. It appears equally difficult to offer something relevantly new which could generate a break-through in exploration thinking and cause a marked improvement in the ratio of successful undertakings to the total exploration projects started. On the other hand, a number of experts in recent years have urged that the problems in prospecting be analyzed in a more skillful and sophisticated manner than in the past. Their thesis is based mainly on the premise that the cost of finding mineral deposits will increase with increasing technical difficulties. In present large-scale exploration ventures, especially in those regions where outcrops and immediately visible geologic evidence are scarce, older methods of prospecting are increasingly being replaced by more indirect and systematic geophysical and geochemical methods with more emphasis on correct statistical design of exploration patterns. It is perhaps the oil industry which has made the greatest strides in developing statistically, well justified patterns in its search for oil; possibly because oil seepages, as indicators of the presence of oil, left off at an earlier point in time than did outcrops as indicators of base metals. Among the pioneers in the field of statistics and operations research, as applied to mineral exploration, the excellent works of Allais, Slichter, Koop-man, Mickey, de Guhnin, Krumbein, Griffith, Sichel, Krige, de Wijs, and Matheron may be mentioned. It should, however, be pointed out that three subjects of basic importance to the allocation of exploration efforts have so far received only scant attention in published literature, even by the aforementioned authors. In the first place, a more precise definition of the object of the search, i.e., a minimum-size orebody, seems to be outstanding. Secondly, a decision model is not a widely-discussed subject. Thirdly, no concentrated attempt so far seems to have been made to establish probabilities of the occurrence of economic deposits on a regional scale and to arrive at a slightly more accurate knowledge of the probability laws governing the deposition of ore. It is not the purpose of this paper to create new order in the complexity of uncertainties in which our decision processes in exploration necessarily have to be conducted. Rather, we intend to highlight some of the outstanding, hitherto unmapped territory, where diligent compilation and a utilization of present and historic data may statistically improve our chances of success. We hope that the contribution of this paper will lie in bringing allocation problems into better focus and in increasing the mineral industry's realization of the magnitude of the factors involved. THE MINIMUM-SIZE OREBODY The concept of target specifications for what constitute a minimum-size orebody in exploration is a rather variable one and depends to some extent on

Jan 1, 1963

THE SOUTHWEST MINING SECTION of the National Safety. Council held a well attended two-day conference at Globe, Ariz., March 19 and 20; followed by two days of mine-rescue maneuvers at the Old Dominion mine in cooperation with the Globe-Miami District Mine Rescue and First Aid Association and the U. S. Bureau of Mines. C. L. Colburn of the Bureau had general charge of the arrangements and was chairman of the conference. All sessions were held in the Old Dominion Library. The program of papers was as follows: MINE FIRE PREVENTION AND FIGHTING What to do in Case of a Mine Fire. / Chas. A. Mitke, Consulting Mining Engineer, Bisbee, Ariz. Gunnite as a Fire Preventative. W. C. Browning, General Manager, Magma Copper Co., Superior, Ariz. Chemical Engineer's Part in Fire Fighting. Dr. L. H. Duschak, Consulting Chemical Engineer, San Francisco, Cal. Mine Fire Drills. A. C. Stoddard, Chief Mining Engineer, Inspiration Consolidated Copper Co., Inspiration, Ariz. Notes on the Installation of Fire Fighting Equipment in Mines. Benjamin F. Tillson, Assistant Superintendent, New Jersey Zinc Co., Franklin, N. J.

Jan 5, 1923

NEW MEMBERS The following list comprises the names of those persons who became. members during the period Sept. 10, 1918, to Oct. 10, 1918. ADDISON, HERBERT, Vice-pres. and Mgr., Big Horn Collieries Co., 412 Colorado Bldg., Denver, Colo. ALLAN, .ANDREW, JR A. Allan & Son, Harrison, N. J. AMI, HENRY M., Charge of War Metals and Minerals, British Embassy, Washington, D. C. ALTHAR, HOMER C., Mill. Engr., The Lorain Coal & Dock Co., Bridgeport, Belmont Co., Ohio. BASER, JOHN T Pres., J. T. Baker Chemical Co., Phillipsburg, N. J. BARBA, W. P., Lieut. Colonel, Ordnance, U. S. A., 2301 Connecticut Ave., Washington, D. C. BENSON, JOHN PATS Min. Engr., Aurora Cons. Mines Co., Aurora, Nev., BOSWELL, H. F Resident Inspector, Southern Railway System, St. Louis, Mo. BRAUCHER, PETERS., Foundry Mgr., Philadelphia & Reading Ry. Co., Sixth & Perry St., Reading, Pa.

Jan 11, 1918

By Albert Sauveur

(New York Meeting, February, 1913.) IT is delightful to read a technical paper like that of J. E. Johnson, The Effect of High Carbon on the Quality of Charcoal-Iron, presented in October, 1912, at the Cleveland meeting of the American Institute of Mining Engineers.1 The clear, simple, and straightforward manner in which he describes his experiments and results makes you feel as if you had been, so to speak, at his elbow during the course of his investigations, while his method of procedure is so rational that you can fairly anticipate each step in the logical sequence of the tests performed. The following notes suggested by Mr. Johnson's paper are presented here in the hope that they may help, if only a mite, towards the final solution of a problem of considerable scientific and industrial importance.

Jan 3, 1913

By G. J. Saulnier, K. E. Goddard

The US Geological Survey has developed mathematical modeling techniques to assess potential impacts on the hydrologic system resulting from mining of coal and oil shale in northwestern Colorado. Potential impacts of oil shale mining on groundwater hydrology have been simulated using a quasi-three-dimensional, finite-difference model. The model has been used to simulate hypothetical mine dewatering operations at two proposed oil shale mines. Dissolved-solids distribution and solute transport were simulated with a three-dimensional, finite-difference model that was used to evaluate the effects of flooding in hypothetical abandoned mines. The potential impacts of coal and oil shale mining on water-sheds were investigated using a digital watershed model. This deterministic physical-process model predicts responses of the hydrologic system to modifications resulting from mining in basins having snow as the major source of runoff and recharge. Potential impacts of coal development on surface water quality were investigated using a river quality assessment model. The models developed by the US Geological Survey have been useful in defining the potential effects of mining in northwestern Colorado. They are an important first step in analyzing the existing data base and in predicting impacts and new data needs. The models may not be totally applicable on the local scale but are very meaningful on the regional level.

Jan 1, 1983

By Norman Weiss

IF we were to measure progress this year in terms of large new mills and discoveries of fundamental significance we should certainly be disappointed. Outside of the uranium field there was little of a spectacular nature. San Manuel and Reserve completed their first year of operation; Erie approached readiness; the Toquepala project in southern Peru broke ground and gained speed. Important mill enlargements occurred at Inspiration, Anaconda, Ray, and Climax Molybdenum. A 3000-ton copper concentrator was completed at Pima, near Tucson. The Republic Mill of Marquette Iron Mining Co. started up in April. Abroad, the great developments in the African Copper Belt can be likened to the rapid growth of the porphyry coppers in this country. Fundamental research was confined nearly entirely to iron ore flotation and recovery of metal values from leach solutions, particularly uranium. The large number of review articles this year reflected a desire to take stock and consolidate past gains before taking the next bold steps. Undoubtedly a shortage of competent young engineers and technicians is stunting the natural growth of theoretical investigation in the field of minerals beneficiation, as well as the conversion of ideas into action. We find our small stock of talented young scientists concentrated in a few centers of erudition because there are not enough to diffuse through the industry. It is safe to say that among mine administrators and managers there is more interest in the education, training, and welfare of the young engineer than ever before.

Jan 2, 1957

NEW MEMBERS The following list comprises the, names of those persons who became members during the period June 10 to July 10, 1914: Members ALDRICH, HAROLD W., Supt. of Leaching Plant, Washoe Red. Wks., Anaconda Copper Co., Anaconda, Mont. AYER, FRANK ASHTON, Mine Foreman.. ..Detroit Copper Co., Morenci, Ariz. BELL, ARTHUR F. L., Chief Engr., Associated Oil Co.., 817 Sharon Bldg., San Francisco, Cal. BERGMAN, JULIUS GUSTAF, Mech. Engr., Chief Draftsman, Arizona Copper Co. Morenci, Ariz. BURT, CURTIS F., Min. Engr., Pittsburg-Dolores Mining Co., Rockland, via Yerington, Nev. CALLAWAY SCOTT DAVID, Chem La Harpe Smelter Co., La Harpe, Kan. CAMPBELL, W. C., Min. Engr 4 Princess St., Roodeport, Transvaal, So. Af. CARROLL, GEORGE A., Genl. Mgr Kildare Min. Co., Manson, B. C., Canada. CARUTHERS, JOHN LYTLE, Min. Engr., Asst. Engr., St. Louis, Rocky Mountain & Pacific Co.. Raton. N. M.

Jan 8, 1914

By Robert Isaac Williams

The Questa mine is located in northern New Mexico on the western flank of the Sangre de Cristo Mountains about 75 miles north of Santa Fe and ranges in elevation from 6,800 to 10,000 ft. GEOLOGY The rocks of the area are Precambrian metamorphic rocks covered by Tertiary extrusive andesites and rhyolites and intruded by Tertiary granitic rocks. These Tertiary intrusives are localized in an east-west belt about 20 miles long and 2 miles wide, extending from Questa to Red River. The Questa orebody is associated with a north-trending aplite intrusive about 3/4 mile wide and 1 3/4 miles long. In the area of mineralization, the metasomatism of aplite has produced a mottled porphyritic rock. This hybrid rock has caused much of the controversy about the Questa mine intrusive. The orebody is essentially monomineralic and consists of numerous closely spaced molybdenite veins varying in thickness from ' 'paint" to 3 in. and occurring in both the andesites and the intrusive. In the intrusive the veins are often siliceous. Common alteration minerals associated with the molybdenite ore vary with the original composition of the rock. The alteration of the aplite has produced phenocrysts of orthoclase, albite, oligoclase and biotite; veins of quartz, orthoclase, and biotite; and graphic myrmekitic intergrowths of feldspars and quartz. In many places near the contact, the andesite is indistinguishable from the metasomatized aplite. The dominant alteration in andesite, however, is the development of fine-grained biotite with apatite, rutile, and sphene.

Jan 1, 1969

By N. J. Keys, B. Barlin

Operating properties of Bancroft Mines Ltd. are in the Western Province of Northern Rhodesia, just south of the Katanga border and at the north- western end of the Rhodesian Copperbelt. The concentrator, above, was commissioned in January 1957 to treat 150,000 tons per month of ore derived from the nearby Kirila Bomwe South orebody, and the Konkola orebody eight miles away. The Konkola orebody is comparatively low grade and mining was discontinued there in early 1958. Development work on the new mine at the Kirila Bomwe North orebody commenced in 1959. Today, the plant treats approximately 150,000 tons of ore per month from the Kirila Bomwe South orebody and development ore from the north orebody. Ultimately, 100,000 tons of ore per month will be produced from the north orebody.

Jan 9, 1963

By Robert H. Carpenter

Molybdenite mineralization occurs in the hood zone of the Questa mine aplite-porphyry intrusive, one of the three sil ica-rich intrusive5 occurring along the east-west trending Red River Trench that crosses the northerly trending Sangre de Cristo Mountains in north-central New Mexico. The Trench is located immediately north of the circular Gold Hill positive block between the Red River and Cabresto Creek drainages. The aplite-porphyry bodies intruded a mid-Tertiary volcanic section consisting of lower andesites, overlain by latites and rhyolites. They occur largely in the andesites and were emplaced mainly by metasomatism rather than by sloping. Hydrothermal alteration occurs both as blanket propylitization in the volcanics and sericitization and kaolinization in the porphyries and as halo-type alteration outward from veins and shear zones resulting in strong biotization in the volcanics and sericitization and kaolinization in the aplitic rocks. Mineralization consists of: ( 1) molybdenite- quartz veinlets; (2) banded molybdenite, quartz veins frequently with biotite and potash feldspar along the walls and occasionally with minor lead, zinc, and copper sulfides and with fluorite and carbonates when again reopened; ( 3) high grade molybdenite locally along shear zones; and ( 4) molybdenite paint along joint and fracture surfaces. The mineralization was associated with faulting that resulted from numerous periods of gravity adjustment along the Trench and was controlled by the major shear systems that trend northeast, east-west and north-south to northwest. Molybdenite has been well oxidized in nearsurface exposures to ferrimolybdite and the molybdenum-bearing ferric hydroxide, akaganeite. The oxidation of the abundant pyrite within the veins and shear zones and of the alteration pyrite in the volcanics resulted in a low pH environment under which the acid molybdate ion released by oxidation was fixed either in the ferrimolybdite or the akaganeite molecule in the veins and shear zones or in the soils. Little has been lost in the runoff.

Jan 1, 1968

Ira B. Joralemon, one of the world's most noted mining geologists, died last year at the age of 91. "His long professional career," says Donald H. McLaughlin, chairman of the executive committee at Homestake Mining Co., "covered an epoch in the history of mining that was unique in its opportunities and achievements," adding that many mining companies (Bunker Hill, Bralorne Mining, Copper Range, Anaconda, Newmont, Phelps Dodge, Homestake, etc.) greatly benefited from Joralemon's experience and wisdom.

Jan 12, 1976

By Charles Fettke

IN 1914, the officials of the Brundred Oil Corpn., faced with the problem of introducing new methods to increase production in the old and nearly depleted pools of Venango County, became interested in the Smith-Dunn (Marietta) process which was at that time being tried out in southeastern Ohio and which was already yielding very encouraging results. A license to use the process in Pennsylvania was secured from the owners of the patents. These patents were later declared invalid. The method was first used in Pennsylvania on a property consisting of about 434 acres, of which 300 are productive, at Hamilton Corners, 15 miles northeast of Oil City, in Cherry Tree and Oakland Townships, Venango County. The producing horizon is the First Sand of the Venango Group. A small oil pool was opened up in this vicinity in 1904. By July, 1916, when the compressed air was first introduced to restore pressure, the production had dropped to a point where it was no longer possible to continue profitable operation. From that time until March, 1927, over 100,000 bbl. of oil have been recovered from the tract. The property is being operated at present by the Brundred Oil Corpn. and Lux. The 1926 production, amounting to 10,650 bbl., was only 400 bbl. short of the maximum reached during any year of the 10-year period that the process has been in operation. Inasmuch as the Hamilton Corners pool is the first one in Pennsylvania in which the Marietta process was tried out, and the one in which it has been longest in continuous operation, considerable interest attaches to the results obtained. Through the courtesy of H. D. Brown and W. J: Brundred, officials of the Brundred Oil Corpn., all their data on this operation were made available to the writer in connection with an investigation of rejuvenation methods in the State for the Pennsylvania Geological Survey.

Jan 1, 1928

By David R. Mitchell, R. M. Fleming

MANY trends were evident in the coal industry during 1951. Some were favorable for the industry; others were not. Probably those having the most far-reaching consequences are those affecting coal's markets. The rapid dieselization of many railroads and the continued trend toward oil and natural gas for home heating has caused serious dislocations in various mining districts. Mines have been forced to close down or to work on a reduced time basis. Conversely the increased activity in the metallurgical industries has increased the demand for coking and special purpose coals, and the growing production of electric energy has increased the demand in certain areas for steam coals. The increased demand for metallurgical coal and for steam raising by the large utilities is more than equal tonnage-wise to the loss of coal to railroad dieselization and conversions to oil and gas in the domestic market. Since much of the expansion is at captive mines of large corporations, many commercial operators supplying railroad and domestic users have had their markets curtailed without any compensating demand from other sources. Feverish activity was in evidence in many areas by commercial operators attempting to find new markets. The Norfolk and Western Railway is the, only major American railroad committed to the burning of coal. It has an exceptionally good cost record. During 1951, fifteen additional modern coal-burning steam switching locomotives were authorized for construction in the company's Roanoke shops at a cost of about $1,450,000. When the new order is completed the road will own a total of sixty locomotives of the modern-switcher type, including thirty acquired by purchase last year. The Norfolk and Western today is the only American railroad building its own motive power. All of these locomotives burn coal. Production Coal production in the year 1951 will approximate 570 million tons of anthracite, bituminous coal, and lignite. Of this, approximately 7 pet is anthracite. Total production is approximately 30 million tons more than in 1950 and reflects the increase in general industrial activity. Exports are expected to be close to 50 million tons. The industrial stockpile is close to 75 million tons, the highest it has been since 1943. With the exception of the usual local stoppages the year 1951 was unmarked by labor disputes. It was a year of good labor-management relations with a negotiated wage increase unmarred by a work stoppage. This may be the beginning. of an era of sensible negotiations to find agreeable settlements of disputes without the usual protracted bickering and industry-wide strike. The United Mine Workers of America has condemned wildcat strikes, stating that in nearly every, instance proper grievance procedures have not been instituted. Government defense organizations, perhaps profiting by their experiences during World War II, are pursuing a more enlightened program with regard to the fuel requirements of the nation. Many prominent officials have stated that wherever possible coal should be considered the primary source of fuel in all defense expansion. With the increased consumption of steel by defense projects, approval of transportation facilities for liquid and gaseous fuels have been refused where these fuels would enter a coal producing area. Liquid and gaseous fuel producers also have failed to provide satisfactory evidence that they have sufficient reserves and are capable of supplying their product in adequate amounts for the periods of time required. Realization has at last become prevalent that the hydro-electric power installations in several areas are insufficient to handle increased demands.' Steam generating plants are being constructed in these areas and equipped to burn coal. Most notable of these, is the TWA area whose supplemental steam power plants are expected to consume 10 million tons of coal per year when completed. The Pacific Northwest is another area which is expected to follow the same pattern. Nearly all new steam-power generating plants are being equipped to burn coal either as a primary fuel or as an emergency measure. Metallurgical Coal The steel and other metallurgical industries are expanding rapidly to meet increased industrial demands and defense orders. Since these industries are dependent on coke, coke has had a year of high production and can be expected to break all existing records when steel-plant expansions are completed. Most notable of the expansion projects is that of the Delaware River area where the iron ore will be received by ship from Canada and South America. U. S. Steel is only one of several steel corporations that are planning on putting integrated steel producing units in this area. The Defense Solids Fuels Administration announced in December that through. November 30, 1951. 29 projects in eight states, with a total cost of

Jan 1, 1952

In 1846 a bill was pending in Congress to reduce, or eliminate, the tariff on coal; the debate caused the same writer to visit the mines on the north side of the James River and to write a letter about them to the same paper.' Omitting the political arguments, his account follows: "July 13, 1846. "Early in the morning we rose, washed, combed, and ate a first-rate breakfast, and then went to the Tuckahoe, mined by Messrs. Sneed and Dietrock. Coal was first discovered here sixty years ago, and mined by Colonel Thomas Randolph, the proprietor of the land. They were worked by him for his smith-shops. Since which time they have been worked periodically, up to the war of 1812, when they were abandoned; and recommenced in 1837 under the management of Dr. W. T.- Scott. Subsequently a Company was formed called Tuckahoe Coal Mining Company, which purchased the whole track at a cost of $30,000. They commenced the sinking of a shaft and went as far as 412 feet, and then pitched the fat all into the fire by hauling off altogether in despair. In 1843 Major Sneed went to work at it, and succeeded. I may here remark that Major Sneed has been the pioneer in this business on the North side of the River, and has sunk more shafts than any other man who has pursued this vocation in Eastern Virginia. The difficulties and expense in sinking these shafts are sometimes immense. The coal on the outcrop or surface is not always a guide to where it may be found imbedded many hundred feet under earth and rock. "The Tuckahoe Pits are on the Eastern end of the coal field, within twelve hundred yards of the Canal, and about twelve miles from Richmond. They employ fifty hands and raise some three hundred thousand bushels of coal per year. It is highly bituminous and excellent for the manufacture of iron. The Tredegar and Belle Isle Rolling Mills are supplied with it. It must be good and of the right kind', or they would not use it. These pits are the only. ones on this side troubled-with gas-of course ventillation is necessary. There is not as much water in this Pit as I have found generally in many others, although they have extended their operations to a considerable distance under ground. I have observed in examining the coal mines, that, where they are sunk over four or five hundred feet, they are annoyed by gas, and where there is a less depth they are troubled with water. It is evident, therefore, that water, in the region of these coal fields, does not run through the earth to any extent, even five hundred feet deep, and the farther you go below that the greater the increase of gas. "We next visited William Cottrell's Pits, situated one mile and a half north of this. He employs some thirty hands, and raises from 4 to 500 bushels per day. "T. & R. Crouch's Pits are one hundred yards north of Cottrell's. This firm employ from 80 to 90 hands, and raise from 8 to 900 bushels per day. They are now

Jan 1, 1942

By Russell A. Carter

Seven years of rising silver prices have effectively revived an historic Idaho mining district and given it a new lease on life. Initial production earlier last year from the DeLamar open-pit silver mine in southwestern Idaho ushered in a new era of mineral production in a region that has weathered boom-and-bust cycles reaching back the better part of a century.

Jan 1, 1978

J. R. Lane (Metals Research Laboratory, Washington)—A new type of deformation called "kinking" has recently been described. Is there any relation between the "rumpling" described in this paper and "kinking?" D. C. Jillson (author's reply)—Both are manifestations of bending about [210] axis. The difference is one of degree. W. C. Ellis (Bell Telephone Laboratories, New York) —Some observations of deformation in zinc recorded in this paper may be applicable generally to flow in metals. One of these, deformation in torsion without evidence of slip or twinning in the early stages and with startling ease, when the twist is about the hexagonal axis, adds another method of flow to the presently increasing list of mechanisms. This illustrates again that a crystal will utilize any realizable process to flow and relieve stress. The process is not necessarily classical directional slip—& this case, it is rotational slip. The question naturally occurs: Will face-centered cubic metas stressed by twisting about an octahedral axis flow in a similar manner by rotation on an octahedral plane? I would like to ask Dr. Jillson if he has made any experiments or knows of any experiments of this type on face-centered cubic metals? Face-centered cubic metals possibly would behave differently from zinc, since, for one thing, the stacking sequence is different for the two structures. The results of such experiments, however, would be instructive in providing more information about deformation processes. D. C. Jillson—Dr. Roy E. Swift, working in the Hammond Laboratory at Yale, performed a twist test on a single crystal of brass. The work has not been published, and I do not know the crystallographic direction of the axis of the specimen used. Lo-ching Chang (Columbia University, New York)— Observations similar to Figs. 1 and 2 of the paper were obtained by us during the bending and unbending of an orthorhombic Au-Cd alloy.'l This orthorhombic alloy is the product of diffusionless transformation from a single crystal of p Au-Cd alloy (CsC1 structure) containing 47.5 atomic pct Cd on cooling to about 60 "C.62 Referring to the effects of annealing, has the author tried any loilg time high temperature anneal, such as 150 to 200 hr at 40O°C? D. C. Jillson—No. C. Crussard (Ecole des Mines, Paris: France)—I

Jan 1, 1952