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By Oliver Bowles

Dimension stone is a term applied to stone sold in blocks or slabs of specified shapes and usually of specified sizes, contrasted with crushed, broken and pulverized stone covered in another chapter. Dimension stone includes cut stone, rough building stone, ashlar,* rubble, monumental stone, paving blocks, curbing, flagging, and many types of ornaments and novelties carved from stone. Riprap-large, irregular blocks used for shore protection-is classed with crushed and broken stone. Composition, Varieties, and Properties Dimension stones are of many kinds. The principal varieties are granites, trap rock (diabase, basalt, and gabbro), sandstone, limestone, and marble. Slate is covered in a separate chapter. Granite is a visibly granular crystalline rock consisting essentially of feldspar, quartz, and mica or hornblende. The basaltic rocks are darker in color than the granites. They contain little or no quartz and consist largely of plagioclase feldspar, augite, pyroxene, and hornblende. They are classed commercially as black granites. Limestone consists essentially of calcium carbonate. Dolomites and magnesian limestones used as dimension stone are classed with the high-calcium limestones. Marble is a crystalline form of limestone, but in the trade, any carbonate rock which will take a polish is called a marble. Many limestones which are fossiliferous but which will take a polish are sold as a decorative stone for lobbies of hotels and office buildings. Sandstone consists essentially of silica in the form of sand grains cemented into a coherent mass. Although rock occurrences are numerous and widespread, the exacting requirements of use condemn all but a small fraction of them for commercial use as dimension stone. No deposit that has closely spaced joints or planes of weakness can be used because sound blocks of moderate to large size are demanded. Uniform texture and grain size, constant and attractive colors or color pattern, and freedom from impurities that may cause stains or deterioration usually are demanded. Hardness is a variable property. Granites and diabases are as hard as or harder than steel, while limestones and marbles may be scratched with a knife. The hardness of sandstone depends upon the degree of cohesion of the grains. Workability depends to a considerable extent on hardness, but the degree of hardness has little influence on use except where stones are subjected to abrasion as on steps or floors. "Texture" as applied to stone relates to the arrangement, uniformity, and size of the constituent grains. Stones are of many colors and thus can satisfy a variety of tastes. For monumental stone, a marked contrast between polished and tooled surfaces is preferred in order that inscriptions may be read easily. Strength requirements usually may be disregarded because any sound structural stone suitable in other respects is almost invariably many times as strong as would be required for any ordinary use. The pressure on the base course of the Washington Monument, Washington, D. C., is less than 700 psi, and highgrade granites, limestones, sandstones, and marbles will sustain a crushing load of 10,000 to 25,000 psi. A structure made of stone with a crushing strength of 15,000 psi would have to be nearly 21h miles high before crushing of the lower courses would occur. However, stone disintegrates more readily under severe

Jan 1, 1960

By J. E. Spruiell, F. H. Patterson, B. F. Shuler

The microstructures and textures developed by the working of high-purzly thermochemically deposited tungstem sheet have been inuesligated. Greater than 60 pct reduction was required to deslroy the columnar grain structure which existed in the as-deposited sheet. With increasing reductions the texture gradu-ally charged from the initial as-deposited orientation with (100) parallel to the sheet normal to a (100}(011) ideal ovienlation with some spread about the rolling direction. This texture was retained after recrystalli-zation a1 2000°C. THE processes for depositing tungsten by hydrogen reduction of tungsten hexafluoride have been under development for the past several years.1,2 The nature of the deposition process is such that the as-deposited material contains a highly oriented columnar grain structure perpendicular to the deposition substrate. This well-defined columnar structure may be useful in certain applications293 but a wrought or equiaxed structure may be desired for some components such as tubing. Knowledge of the effects of working ther-mochemically deposited (TCD) tungsten is therefore necessary in order to establish the feasibility of obtaining worked and recrystallized microstructures and textures. The details of a recently developed technique for thermochemically depositing flat, uniformly thick tungsten sheet are presented with emphasis on the effects of deformation by rolling on the microstructure and texture. Although no work has been previously reported on the rolling and the annealing textures of TCD tungsten, there have been some determinations of textures for cold-rolled tungsten foil prepared from powder-metal -lurgy billets.4-8 The general description is that of a predominantly lurgy{100}(011) texture, with some spread about the rolling direction as an axis. pugh5 reports data both for cold-rolled and for annealed foil having about 96 pct initial cold work. He observed no change in texture, except for a decrease in the spread, for annealing treatments of 30 min at temperatures up to 1800°C. On annealing at 1900°C, both the low-temperature components plus new components which were described alternately as {001}(320) plus {001)(230) or as {100}(011) ± 12 deg about the sheet normal were observed. Above 1900°C, the new orientation existed alone, and it was stable up to 2500°C, the highest temperature that Pugh investigated. THERMOCHEMICAL DEPOSITION OF TUNGSTEN SHEET High-purity tungsten sheet was reproducibly deposited on the inner walls of a molybdenum mandrel by the thermochemical reaction WFs(g) + 3H2(g) - W(s) + 6HF(g). The mandrel was heated by a five-zone tube furnace which afforded a controllable fixed-temperature profile. Sheets measuring 1+ by 12 in. have been deposited with uniform thicknesses of up to 0.145 m. As shown schematically in Fig. 1, the purified reaction gases were metered into a mixing chamber at a Hz-to-WF6 ratio of 15 and preheated to 350°C. The flow rate of the WF6 was 300 cu cm per min at stp. These gases were directed through a conical injector into the deposition chamber. Inside this chamber hydrogen reduction of the WF6 to pure tungsten metal occurred on the hot walls of the molybdenum mandrel at a total pressure of 5 Torr. Typical temperatures for the five zones in the chamber were, respectively, 565", 540", 550°, 570°, and 590°C. The hydrogen fluorlde generated from the reaction, the excess hydrogen, and some un-reacted WF6 were pumped on through the scavenger

Jan 1, 1968

By F. P. Nichols, F. A. Renninger

At one time, mineral aggregates were considered physically and chemically inert substances whose junction was that of an inex-pensive, easily obtainable source of bulk. This philosophy applied regardless of the use to which the aggregate was put. Research approaches dealing only with such gross physical properties as hardness, toughness, impact resistance, etc., dominated the early growth years of the industry and influenced specifications to a large extent. The accelerated pace of highway construction, which began toward the end of the depression years, focused attention on the need for extensive aggregate research. The realization in the early 1940's that aggregates interacted chemically as well as physically with their environment provided the stimulus necessary to translate the drab, systematic aggregate technology of the early 20th century into the changing, dynamic, challenging field it is today. Current research problems are discussed in detail. These efforts being pursued by contract research organizations, universities, governmental agencies, and industry transcend many fields. The mineral aggregate industry is the world's largest mining and processing endeavor, yet it is graced with little of the romance or public awareness that accompanies mention of gold, silver, iron, copper, uranium, or aluminum mining efforts. Much of this reaction is undoubtedly due to the fact that the uses to which crushed stone and sand and gravel are normally put are not fully recognized or appreciated by the general public. Almost 2 billion tons of mineral aggregates are quarried or mined, processed, and sold yearly in the United States alone.= The largest uses to which this vast tonnage is subjected are as ingredients of portland-cement concrete, bituminous concrete, and dense-graded aggregate-base course mixtures in the highway and building construction fields, two industries closely related to the expenditure of public funds. It is for these uses, partially in justification for the expenditures of vast sums of public funds, that mineral aggregate research truly finds its emphasis. The research efforts expended relative to the highway and building construction uses to which mineral aggregates are subjected are those of primary concern to the industry. These efforts, while of direct consequence to the industry due to the volume market represented, are of interest as well to public agencies, universities, and contract research firms. All actively conduct research, exchange information, and make contributions to the overall knowledge relative to aggregate usage and limitations. The research efforts of the mineral aggregate industry is the subject to be discussed throughout this paper. It covers all aspects of highway and building design, construction, and technology. The effects of research pertaining to quarrying and mining methods, blasting and processing techniques, storage and handling facilities, and equipment employment and development have left their mark on the crushed stone and sand and gravel industries. Such specialized efforts have resulted in dramatically increased production rates which in turn have served to keep costs, and hence prices, down. Despite the many inflationary pressures over the years, the cost of a ton of aggregate today is little more than it was 25 or 30 years ago. Mention is made of these efforts simply to emphasize the diversity of research in the mineral aggregate field. The remainder of this paper focuses on the complexity of what might be termed "product knowledge" research.

Jan 1, 1971

By H. N. Hall

Reservoir and producing characteristics can govern the decision to use either a one-, two- or three-dimensional model for making predictions for gravity-drainage reservoirs. Examples of conditions requiring one-, two- and three-dimensional calculations are given. In 1961 the author presented a method for predicting one-dimensional gravity-drainage performance. This work has been exrendcd to obtain a three-dimensional model, which is described and for which a sample problem is presented. Introduction Many papers on gravity drainage or gas-cap drive'-3 have been presented for conditions where the reservoir is treated as a single areal segment so that, in effect, only one-dimen-sional flow is considered. Other authors'-Q ave given evidence showing that the one-dimensional concept would be unsatisfactory to predict reservoir performance for certain types of reservoirs. Experience has indicated that specific reservoir and producing conditions govern whether one-, two- or three-dimensional concepts must be used as a basis for reliable reservoir performance predictioils. Previously the author presented a paper outlining a method for predicting the performance of gravity-drainage reservoirs.' That paper treated the reservoir as a single areal segment so that it was applicable for only one-dimensional flow. The work has been extended to obtain a three-dimensional model that can be used to predict performance of gravity-drainage reservoirs. Although capable of being three-dimensional, it can be used equally well for one- and two-dimensional predictions. This paper discusses those reservoir and producing conditions governing the choice of model, and also describes a three-dimensional model suitable for predicting reservoir performance in the more complex situations. Discussion The Choice of Model To predict reservoir performance, it is necessary to represent the reservoir by a physical model. A mathematical model, based on the assumed physical model, then is used to predict the movement of oil and gas within the reservoir. The word "model" is used here to connote the combination of both a physical model and a mathematical model based on the physical model. Certain types of reservoir situations may be predicted suitably with a one-dimensional model, whereas two- and three-dimensional models may be required for other situations. This section illustrates reservoir conditions associated with the use of a specific type of model. Many types of reservoir structures are such that gravity drainage possibly could be an important factor in oil production. Production practices, as well as the nature of the structure. can influence the type of model that should be used. obviously, it is impossible to discuss all combinations of reservoir structure and production practices that might be encountered in gravity-drainage reservoirs. The following are typical examples of conditions where a choice must be made among a one-, two- or three-dimensional model to predict reservoir performance satisfactorily. Conditions Requiring a One-Dimensional Model Fig. la shows contours for an asymmetrical anticline in which gravity drainage might be expected to be important. Fig. Ib depicts a cross-section along Line A-A in Fig. la. Existence of a gas cap is a good clue that gravity drainage will be an important factor in producing oil from this type of reservoir. However, it is not essential since a gas cap will form as oil is produced from the reservoir. If the proper combination of reservoir permeability and withdrawal rates is present, the reservoir will behave like a

Jan 1, 1969

By M. TAYLOR

AT Grand Saline, some 65 miles east of Dallas, the Morton Salt Co. of Chicago has for some years operated a brine pumping and evaporation plant on a salt dome. They recently drilled trial holes to obtain data on the dome, preparatory to opening, a new mine, with the following results: The dome is in the form of a truncated cone, with an average of 210 ft. of cover. The top of the dome is approximately one mile in diameter, with the town of Grand Saline lying over the northern rim, and the sides slope off at an angle of 50" to 80" from the horizontal. The deepest holes were drilled to 900 ft. without penetrating beyond the salt, and indications are that the salt deposit is several thousand feet thick. As the deposit increases in area with the depth, there is undoubtedly enough salt to supply a mining operation for an almost unlimited period of years.

Jan 1, 1930

By Ovid W. Eshbach

ENGINEERING education has been powerfully affected by the impact of war, just how powerfully can be better understood after considering the postwar problems regarding students, staff, and plant. In time of war no one will question the necessity of expediency of military training. With the cessation of hostilities, expediency gives way to the evolutionary process of strengthening engineering education as need is exemplified by experience. During the war, except for the Navy V-12 program, engineering education was at its lowest ebb of the century. Freshman enrollments were largely limited to those graduating from high school at the age of seventeen; and the upperclass, to those disqualified for active service. In most schools the experienced staff was either in service or government and industrial research. Many may never return to their former occupations. The most immediate problem is that of maintaining and building a staff to meet the enrollment of returning veterans. It is estimated that out of the eleven

Jan 1, 1945

By S. G. Lasky

EVENTS during and since the war indicate that the nations of the world are trying to initiate an era of international co-operation. Definitions and objectives include social, economic, and human considerations no less than political considerations. The mineral resources of the world and the absolute and relative position of each nation enter into this situation. The possible use of armed might, the application of sanctions, the international flow of commerce, the ways in which this flow may encourage or hamper international well-being, and the influence of international and domestic well-being upon one another are all matters that must take mineral resources into account. If the United States is to act wisely and forthrightly in such matters we must be thoroughly informed as to our position with respect to mineral resources. What is the mineral position of the United States? A variety of widely conflicting opinions are held in authoritative and intelligent quarters: (1) For practical purposes our mineral resources are already exhausted.

Jan 1, 1946

By R. W., Ludt

THE use of froth flotation for the separation of minerals has become one of the most important of ore dressing processes. Its particular adaptability to the enrichment of low grade ores has made the process an important factor in the national economy. The methods have been extended to the recovery of a great number of minerals. Among the few minerals which have resisted efforts toward industrial flotation is chrysocolla, a hydrated partly colloidal copper silicate. Chrysocolla, being a product of natural oxidation, has been found to occur in small quantities with many ores which are recovered by flotation methods. In present practice, these small quantities of copper silicate pass off with the tailings and are lost. The advantages to be gained by a satisfactory process for the recovery of chrysocolla is apparent. Any application of principles which points a way toward the satisfactory industrial flotation process for copper silicate would be of advantage. This paper presents an attack on this problem.

Jan 1, 1949

By AIME AIME

TWENTY-TWO sections and all four of the divisions sent delegates to the annual meeting. They became so interested in the wide ranging dis6ussion of old and yet ever-new problems of Institute affairs that three instead of two sessions scheduled were necessary. Monday morning the meeting assembled with President Bassett presiding in the absence of President-elect Tally, who had been called to Baltimore by the serious illness of a brother. Thursday morning Vice-president Turner presided until Mr. Tally appeared after which the latter guided the sessions. Since reports from all of the active sections save one had been mimeographed and sent in advance to the delegates, detailed reports from each were dispensed with. The discussions dealt largely with membership problems, both local and national, with financing, speakers and programs, visits from national officers, and the conduct of the annual meeting. Many interesting and constructive suggestions were made and will be reported back to the sections by the delegates.

Jan 1, 1931

By J. E. Tobey

BECAUSE of the wide-spread publicity given to Nylon yarn as being made from ?coal, air, and water,? the general public has become conscious of the nonfuel uses of bituminous coal. Some of these uses are as filler for fertilizer, carbon for the absorption of orders, for water supply, and for the bedding of cattle. Spectacular as are these accomplishments the fact is that only a small amount of coal is used for nonfuel purposes. It is on the utilization of coal as fuel that the industry depends. Practically all the coal mines for years to come will be used for making coke for the generation of heat. Recently much attention has been paid to the significance of ash in coal. Another study worthy the interest of metallurgists in the iron and steel industries if that of Dr, Lowry of the Carnegie Institute of Technology relative to the percentage of sulphur in coal and coke.

Jan 1, 1941

By Hugh Marriott

MANGANESE and its ores have been recently dealt with in comprehensive papers to the Iron and Steel Institute by Sir Robert Hadfield, and in a series of papers read before the A. I. M. E. at the Cleveland meeting. I have taken the opportunity of adding this mineral, to my records of the "World's Mineral Production and Consumption," as recently pub-lished in the Economist ?. The tables bring out the following significant facts: The world's production has increased by 10 per cent since 1913. India's production has increased by 3 per cent since 1.913, the supply from this source now being 31.1 per cent of the world's output. Russia is now producing at about half its pre-war rate and yields 19 per cent of the world's production. West Africa supplies 12.5 per cent of the world's total output. Brazil's present output is 2.5 times that of the pre-war period, being 11.3 per cent of the world's output.

Jan 9, 1927

Alexander N. Winchell, Butte, Mont. (communication to the Secretary): Mr. Spurr calls attention to the fact that an ore-deposit may be due to a succession of concentrations at different geological epochs. He cites an example of such a condition on Napoleon creek, a branch of Forty-Mile creek, Alaska. It will perhaps be of interest to call attention to another example of the same general character, not so remotely situated. The example referred to is located on Pole creek, a tributary of Cherry creek, in the extreme northeastern part of Madison county, Montana. An excellent geological map of this region is to be found in the Three Forks folio (No. 24) of the United States Geological Survey. According to this map, Pole creek, in its upper course, occupies the contact between the " Flathead " formation, which Peale correlates with the Middle and Lower Cambrian, and an area of gneisses and schists supposed

Jan 1, 1903

By AIME AIME

The American Society of Mechanical Engineers.-The semi-annual meeting of the American Society of Mechanical Engineers will be held in Detroit, Mich., June 23-26. A session will be devoted to hoisting- and conveying-machinery; and many other subjects will be treated in professional papers, among which are . Clutches (with special reference to automobile clutches); The Thermal Properties of Superheated Steam; The Horse-Power, Friction-Losses, and Efficiency of Gas- and Oil-Engines; A Journal-Friction Measuring-Machine; A Simple Method of Checking Conical Pistons for Stress, and The By-Product Coke-Oven. The usual receptions will be held and excursions will be made to manufacturing plants, the slip-building yards, and various points of interest in and around Detroit. Among the excursions' planned is one to the University of Michigan at Ann Arbor. The Gas-Power Section of the Society will hold a session, and the Society for the Promotion of Engineering Education and the Society of Automobile Engineers will hold meet-

Jan 5, 1908

By AIME AIME

The following persons have been proposed for election as members or associates of the Institute during the period, March 16 to May 1, 1907. Their names are published for the information of members and associates, from whom the Committee on Membership earnestly invites confidential communications, favorable or unfavorable, concerning these candidates. A sufficient period (varying in the discretion of the Committee, according to the residence of the candidate) will be allowed for the reception of such communications, before any action upon these names by the Committee. After the lapse of this period, the Committee will recommend action by the Council, which has the power of final election. The names of candidates were formerly published in the various circulars of the Institute, issued from time to time to the members. Hereafter, they will appear regularly in the Bi-Monthly Bulletin, each number of which will contain the names received since the issue of the preceding Bulletin.

May 1, 1907

"Located on the Big Hole River, three miles from Divide, Montana, and 21.75 miles from Butte.Built in 1899.DAM: Rock-filled wooden crib, 512 ft. long and 57.5 feet high.SPILLWAY: Equipped with flash-boards 189 ft. long, 8 ft. 10 inches high.PENSTOCKS: Two 8 ft. diameter of steel, each branching and supplying two wheels.WHEELS: Four double horizontal, double discharge turbines, made by The James Leffel & Co., 1,000 h-p., 180 r. p. m., direct connected to generators, operating at 60 ft. head. GENERATORS: Four G. E., revolving field, 750 k-w., 180 r. p. m., 800 volt, 3 phase, 60 cycle alternators.EXCITERS: Two water-wheel driven exciters.TRANSFORMERS: 12 250-k-w. G. E. air blast, primary 15,000 volts, Secondary 800 volts.OPERATION: The plant operates essentially as a peak load plant. Except in flood period, there is insufficient water to operate at full load continually. In December its average output is about 500 k-w."

Jan 1, 1913

By F. Rosenblum, P. Spira, F. Kitzinger

The possibility of increasing the efficiency of mineral processing plants by means of computer control has prompted metallurgists to examine their flowsheets more critically in order to develop practical control strategies. Control schemes in use to date generally rely on the automation of traditional and previously manually regulated control loops, e.g., the addition of reagents to maintain a constant assay or a constant pH. This approach is predicated on the availability of well established primary sensors such as pH electrodes or on-stream analyzers. Noranda Research Center, in cooperation with Noranda Group concentrators, has developed a froth level monitor and a pulp density meter adaptable to this type of control. Although some of the basic principles on which they are based have been known for some time, their incorporation into the design of reliable, direct-reading instruments which can be interfaced with a computer is believed to be novel.

Jan 1, 1980

The mines of the country are called upon to bear a very large part of the enormous taxes to be raised for 1917 and later years. The Internal Revenue Bureau, which is charged with the assessment and collection of these taxes, desires that the taxation laws shall be administered in a fair and business-like way. The application to mines, however, which have wasting assets, involves questions of particular complication and difficulty. To meet this situation, there has been established in. the Income Tax Branch, a Section of Mine Valuation in which these specific problems of the industry will be handled by competent engineers. But it is realized that something more than this is required for the satisfactory application of the tax laws to the mines, namely, as complete understanding as possible between the Government and the taxpayer, a spirit of cooperation as between the two and every possible assistance and advice from mine owners and mining engineers.

Jan 9, 1919

Page McGREGOR, A. G.-Features of the New Copper Smelting Plants in Arizona. Discussed by L. D. Ricketts, E. P. Mathewson 2145 HOWARD, L. O.-The Basic-Lined Converter in the Southwest. Discussed by Walter Douglas, E. P. Mathewson, Kuno Doerr 2145 SAMUEL, J. MOORE-Determination of Dust Losses at the Copper Queen Reduction Works. Discussed by Walter Douglas, E. P. Mathewson, S. J. Jennings, C. E. Arnold, A. G. McGregor, L. D. Ricketts 2148 MORSE, H. W., AND TOBELMANN, H. A.-Leaching Tests at New Cornelia. Discussed by H. W. Morse, Lawrence Addicks, G. D. Van Arsdale, S. J. Jennings, F. S. Schimerka, C. G. Grabill, F. N. Flynn, Stuart Croasdale 2151 LAIST, FREDERICK, AND ALDRICH, HAROLD W.-The 2,000-Ton Leaching Plant at Anaconda. Discussed by F. N. Flynn, E. P. Mathewson 2159 ADDICKS, LAWRENCE-Possibilities in the Wet. Treatment of Copper Concentrates. Discussed by F. N. Flynn 2160

Jan 12, 1916

The Motor Truck Sections of the 20th Annual Automobile Shows of 1920, to be held in the 8th Coast Artillery Armory, New York, Jan. 3 to 10, 1920, and in the International Amphitheatre, Chicago, Jan. 24 to 31, 1920, will he the largest and most comprehensive exhibitions of the kind ever held. Approximately 125,000 sq. ft. of exhibition space has been alloted at each place and upward of seventy makes of motor trucks, together with trailers, pacts and accessories will be dis-played. In conjunction with these expositions, Highway Transport Conferences will be held, with sessions each afternoon and evening. Every important phase of highway transportation will be discussed by men recognized as qualified authorities. Various talks will he il-lustrated by motion pictures and stereoptican slides. Members of the Institute may apply for complimentary tickets to-S. A. Miles, Manager, 7 East 42d Street, New York City.

Jan 12, 1919

The Bureau of Mines extends. a cordial invitation to all members of the Institute to visit Pittsburgh, Sept. 29 to Oct. 1, to participate in the dedication of the Mines Experiment Station. Accompanying this will be a nation-wide participation in a First-aid and Mine Rescue Contest. The Pittsburgh Chamber of Commerce will cooperate. The Institute will be represented by a special delegate appointed by the President. MONDAY 8:30. A. M. Bureau Building open for inspection. 10:30 A. M. Dedicatory Ceremonies in rear of Main Building, .4800 Forbes St. 2:00 P. M.. Special Train and Automobiles to Experimental Mine near Bruceton, Pa. 3 to 6 P. M. Mine Explosion and Inspection of Experimental Mine . and of Explosives Testing Plant near Bruceton, Pa. 6:00. P. M. Return by Special Train and Automobiles to B. & 0. Station, Pittsburgh. 8:00 P. M. Informal Reception and Organ Recital Carnegie Music Hall. Arranged by Carnegie Institute of Technology.

Jan 9, 1919